1) Observations of a Lyman-alpha nebula (LAB1) reveal that the Lyman-alpha emission is polarized, with a polarization fraction of around 20% at radii of 45 kpc from the center.
2) The detection of polarized radiation indicates that the Lyman-alpha photons were produced in the galaxies within the nebula and scattered by neutral hydrogen at large distances, rather than being produced in situ.
3) The polarization vectors are oriented tangentially to the overall geometry of the nebula, consistent with theoretical expectations for Lyman-alpha photons produced centrally and scattered at large radii.
1) The document discusses measurements of segments and angles, including obtuse, right, straight, and acute angles. Degrees and minutes are introduced as units of angle measurement.
2) Congruent segments and angles are defined. Collinearity, betweenness, and assumptions are discussed, specifically that points must be collinear to be considered between two other points.
3) The triangle inequality is stated as the sum of the lengths of any two sides of a triangle always being greater than the length of the third side. Cautions are given about assumptions that should and should not be made.
1) KGI Securities' 4Q11 revenue decreased 7.4% YoY to NT$2.816 billion, while net profit decreased 11.1% YoY to NT$67 million.
2) In 1Q12, KGI Securities' revenue was flat QoQ at NT$2.816 billion, while net profit increased 8.2% QoQ to NT$61 million.
3) For 2012, KGI Securities expects revenue to increase 0.5% YoY to NT$12.25 billion and net profit to increase 6.9% YoY to NT$1.412 billion.
1) The 2009 Environmental Report from Ehime University summarizes initiatives related to sustainable development, environmental studies programs, and carbon emissions reductions.
2) Data is presented on forest resources, pollution releases, energy usage, and carbon emissions from 1990-2020 with a focus on reducing impacts.
3) Efforts include the Center for Marine and Environmental Studies, overseas cooperation in environmental fields, and promoting environmental education.
WebElements is a website that provides information about the chemical elements in an interactive periodic table format. It contains details on each element including their name, symbol, atomic number, atomic mass, basic properties and more. The document provides an overview of the periodic table displayed on the site, including information on element names, symbols, atomic weights and organization of the table. It also notes that clicking on an element in the PDF version of the table will link to more details on that element page on the WebElements site when viewed online.
Analytics for http://forensicchemistry.lincoln.ac.uk, Feb/March 2011ulcerd
The document summarizes website analytics for the forensicchemistry.lincoln.ac.uk site from February 20, 2011 to March 21, 2011. It received 45 visits from 11 countries over this period. The majority of traffic came from search engines (53.33%) and referring sites (37.78%). The United Kingdom contributed the most visits (14) and had the highest average pages per visit (2.14) and average time on site (1 minute, 44 seconds). The overall bounce rate was 64.44% and 93.33% of visits were from new visitors.
This document summarizes the Moscow office market report for the first half of 2009. It finds that demand for office space greatly reduced due to the global economic crisis, causing rental levels to fall by more than half. Large volumes of new office space continued to be added to the market, creating an imbalance between supply and demand and causing vacancy rates to rise sharply to 19% for Class A offices. The document also provides details on development projects within Moscow City, the new business center, including the total size, office space, status, and planned completion date for each site.
The reliable determination of stereocenters contained within chemical structures usually requires utilization of NMR data, chemical derivatization, molecular modeling, quantum-mechanical (QM) calculations and, if available, X-ray analysis. In this article, we show that the number of stereoisomers which need to be thoroughly verified, can be significantly reduced by the application of NMR chemical shift calculation to the full stereoisomer set of possibilities using a fragmental approach based on HOSE codes. The applicability of this suggested method is illustrated using experimental data published for a series of complex chemical structures.
1) The document discusses measurements of segments and angles, including obtuse, right, straight, and acute angles. Degrees and minutes are introduced as units of angle measurement.
2) Congruent segments and angles are defined. Collinearity, betweenness, and assumptions are discussed, specifically that points must be collinear to be considered between two other points.
3) The triangle inequality is stated as the sum of the lengths of any two sides of a triangle always being greater than the length of the third side. Cautions are given about assumptions that should and should not be made.
1) KGI Securities' 4Q11 revenue decreased 7.4% YoY to NT$2.816 billion, while net profit decreased 11.1% YoY to NT$67 million.
2) In 1Q12, KGI Securities' revenue was flat QoQ at NT$2.816 billion, while net profit increased 8.2% QoQ to NT$61 million.
3) For 2012, KGI Securities expects revenue to increase 0.5% YoY to NT$12.25 billion and net profit to increase 6.9% YoY to NT$1.412 billion.
1) The 2009 Environmental Report from Ehime University summarizes initiatives related to sustainable development, environmental studies programs, and carbon emissions reductions.
2) Data is presented on forest resources, pollution releases, energy usage, and carbon emissions from 1990-2020 with a focus on reducing impacts.
3) Efforts include the Center for Marine and Environmental Studies, overseas cooperation in environmental fields, and promoting environmental education.
WebElements is a website that provides information about the chemical elements in an interactive periodic table format. It contains details on each element including their name, symbol, atomic number, atomic mass, basic properties and more. The document provides an overview of the periodic table displayed on the site, including information on element names, symbols, atomic weights and organization of the table. It also notes that clicking on an element in the PDF version of the table will link to more details on that element page on the WebElements site when viewed online.
Analytics for http://forensicchemistry.lincoln.ac.uk, Feb/March 2011ulcerd
The document summarizes website analytics for the forensicchemistry.lincoln.ac.uk site from February 20, 2011 to March 21, 2011. It received 45 visits from 11 countries over this period. The majority of traffic came from search engines (53.33%) and referring sites (37.78%). The United Kingdom contributed the most visits (14) and had the highest average pages per visit (2.14) and average time on site (1 minute, 44 seconds). The overall bounce rate was 64.44% and 93.33% of visits were from new visitors.
This document summarizes the Moscow office market report for the first half of 2009. It finds that demand for office space greatly reduced due to the global economic crisis, causing rental levels to fall by more than half. Large volumes of new office space continued to be added to the market, creating an imbalance between supply and demand and causing vacancy rates to rise sharply to 19% for Class A offices. The document also provides details on development projects within Moscow City, the new business center, including the total size, office space, status, and planned completion date for each site.
The reliable determination of stereocenters contained within chemical structures usually requires utilization of NMR data, chemical derivatization, molecular modeling, quantum-mechanical (QM) calculations and, if available, X-ray analysis. In this article, we show that the number of stereoisomers which need to be thoroughly verified, can be significantly reduced by the application of NMR chemical shift calculation to the full stereoisomer set of possibilities using a fragmental approach based on HOSE codes. The applicability of this suggested method is illustrated using experimental data published for a series of complex chemical structures.
The document summarizes a study that uses strong and weak gravitational lensing to analyze the mass distribution of 28 galaxy clusters. Key findings include:
- The concentration parameter cvir is found to steeply decrease with increasing mass, approximately following cvir ∝ Mvir-0.59±0.12, consistent with theoretical predictions for high-mass clusters but observationally inferred concentrations are higher for lower-mass clusters possibly due to baryon cooling effects.
- Stacking weak lensing shear profiles also supports a steep mass-concentration relation.
- Stacking weak lensing shear maps with position angle information from strong lensing indicates significant ellipticity of the mean mass distribution, with a best-fit ellipticity
Searching for signs_of_triggered_star_formation_toward_ic1848Sérgio Sacani
This document summarizes observations of three bright-rimmed clouds - SFO 11, SFO 11NE, and SFO 11E - associated with the HII region IC 1848, using submillimeter continuum data from SCUBA on the JCMT and molecular line data from CO isotopologues. The observations show evidence for protostellar cores within the clouds and recent or ongoing star formation. Based on the morphology and pressures inferred from the data, it is possible the UV illumination from the primary ionizing star HD17505 has triggered the collapse of dense molecular cores within SFO 11 and SFO 11E.
This document summarizes a study of lithium and sodium abundances in stars in the globular cluster M4. The authors obtained spectra for 91 main sequence and subgiant branch stars using the FLAMES spectrograph on the VLT. They detected a weak anti-correlation between lithium and sodium abundances among unevolved main sequence stars. Notably, one star, #37934, showed an unusually high lithium abundance, comparable to estimates of the primordial lithium abundance. This high lithium abundance, coupled with the star's sodium-rich nature, suggests the lithium may have come from pollution by a previous generation of stars, though preservation of the primordial abundance cannot be ruled out. The detection provides new evidence that globular clusters
1) The document presents new observations of shell structures in the halo of galaxy NGC 7600 and a movie from a cosmological simulation showing how shell galaxies can form in a cold dark matter universe.
2) The movie illustrates how the continuous accretion of dark matter and star clumps creates diffuse circumgalactic structures, and how the disruption of a massive clump on a near-radial orbit creates a complex system of concentric shells resembling those of NGC 7600.
3) With the aid of the simulation, the authors interpret NGC 7600 in the context of the cold dark matter model of galaxy formation through the accretion and disruption of smaller companion galaxies.
Modulations in the_radio_light_curve_of_the_typeiib_supernova_2001igSérgio Sacani
This document summarizes radio observations of the Type IIb supernova SN 2001ig made with the Australia Telescope Compact Array and Very Large Array over 700 days. The observations found periodic deviations from the standard model of radio light curves that are consistent with recurring density modulations in the circumstellar medium with a period of around 150 days. This provides evidence that the progenitor was a Wolf-Rayet star in a binary system with an eccentric 100 day orbit, causing regular build-up of circumstellar material. Such binary systems are thought to produce Type Ib/c supernovae through envelope stripping, linking these events to Type IIb supernovae.
This document presents a study characterizing active galactic nuclei (AGN) selected using mid-infrared colors from the Wide-field Infrared Survey Explorer (WISE). The authors find that a simple color criterion of W1-W2 ≥ 0.8 selects AGN with high reliability to a depth of W2 ∼ 15.0, identifying over 60 AGN candidates per square degree. This WISE selection method is effective at identifying both obscured and unobscured AGN. Using deep data in the COSMOS field, the authors explore the properties and redshift distribution of WISE-selected AGN candidates, finding the selection identifies 78% of AGN identified by previous Spitzer studies.
This study examines the clustering properties and redshift evolution of bias for 593 X-ray selected AGN from the XMM-Newton survey in the COSMOS field with spectroscopic redshifts below z=4. The authors find evidence that the bias factor increases with redshift for the total AGN population, from b=2.30 at z=0.92 to b=4.37 at z=1.94. Splitting the sample, they observe a similar increase in bias with redshift for broad-line and unobscured AGN, corresponding to a constant halo mass of logM~13.28 and logM~13, respectively. The observed bias factors cannot be reproduced by models assuming AGN are triggered
This document summarizes Hubble Space Telescope ultraviolet spectroscopy of four white dwarfs known to accrete planetary debris. The spectra reveal absorption lines from a variety of metals including carbon, oxygen, aluminum, silicon, phosphorus, sulfur, chromium, iron, and nickel. Combined with optical data, between five and eleven different metals are detected in each white dwarf, indicating substantial chemical diversity in the accreted planetary debris. The abundances observed provide insights into the composition and origin of the debris, with some debris resembling bulk Earth composition and others showing evidence of melting and differentiation.
This document is the lecture notes from an introductory astronomy course covering Chapter 15 on galaxies. It provides an overview of the course structure, learning objectives, quiz and exam schedule, and links to additional online resources and images of various galaxies presented in the Astronomy Picture of the Day.
At Akvo's Track Day on 6 March 2012, Luuk and Kathelyne gave a workshop about Akvo's RSR.
In this powerpoint presentation, you'll get a tour of Akvo's admin features in the project back-end.
Weighted logratio biplots provide a method for analyzing compositional data that addresses some limitations of unweighted logratio biplots. The weighted approach introduces row and column masses as weights during centering and fitting, which downplays the influence of rare components with high variance. This weighted logratio biplot, also known as a spectral map, has all the properties of the unweighted biplot as well as the additional property of distributional equivalence. When applied to contingency tables, the weighted logratio biplot/spectral map is comparable to correspondence analysis and may be preferable due to its property of subcompositional coherence. The two methods are nearly identical when the data have low variability.
The document presents preliminary results on daily radiation forecasting using statistical methods. It explores using linear and non-linear prediction techniques like TAG(p) and discusses using historical piranometric data from 1996-2003 to predict daily global solar radiation values and analyze the data through partial autocorrelation. The goals are to characterize and predict solar radiation as an energy resource for applications like short and medium term forecasting.
This document discusses citizen science projects focused on biodiversity in Europe. It provides background on citizen science, describing it as scientific research conducted in whole or in part by amateur or nonprofessional scientists. It then highlights several examples of biodiversity monitoring projects in Europe, including waarnemingen.be, waarneming.nl, observado.org, artportalen.se, and naturgucker.de. These projects engage citizens to record and report observations of taxa in nature. The document compares the scale of these projects in terms of numbers of observations, users, and other collected data.
This document provides an introduction and overview of cloud computing. It discusses the growth and adoption of cloud services, defines key cloud concepts like SaaS, PaaS and IaaS, and highlights some success stories and vendors in the cloud space. It also briefly touches on potential pros and cons of cloud computing.
Natalia Restrepo-Coupe_Remotely-sensed photosynthetic phenology and ecosystem...TERN Australia
This document discusses using remotely sensed data and tower eddy covariance CO2 flux measurements to study phenology and ecosystem productivity. It notes that flux tower data can help validate remote sensing phenology products by determining if they correctly capture dates of green-up, peak growing season, end of season, and season length. The document also aims to better understand what vegetation indices mean quantitatively and their biome-specific relationships to in-situ ecosystem behavior and capacity. Improving this understanding could lead to more robust land surface models informed by remote sensing.
This document summarizes research on achieving high reliability and low-cost lead-free solder joints using manganese or cerium doping of tin-silver-copper (SAC) solder. Experimental results show that SAC doped with 0.05% manganese (SACM) or 0.02% cerium (SACC) outperforms baseline SAC105 and SAC305 alloys in drop test reliability and thermal cycling performance. Specifically, SACM and SACC exhibit higher drop test lifetimes and allow packages to withstand higher dynamic bending strains compared to SAC105 and SAC305. This research demonstrates that minor manganese or cerium doping of SAC alloys can improve
T2 Partners Presentation On The Mortgage Crisismdjonesb
This 3 paragraph document provides an overview of the housing/credit crisis and why there is more pain to come:
1) Housing was stable for the second half of the 20th century but then prices exploded from 2000-2006 as lending standards declined dramatically, allowing homeowners to borrow much more against their homes.
2) As a result, the percentage of equity homeowners had in their homes fell below 50% for the first time, leaving many underwater. Private label mortgages like subprime, which were securitized by Wall Street, made up only 15% of mortgages but account for 51% of seriously delinquent loans.
3) Deregulation led to a surge in profits and compensation
T2 Partners Presentation On The Mortgage Crisisrossreller
This document provides an overview of the housing and credit crisis and why more problems are expected. It summarizes that loose lending standards from 2001-2006 led to a surge in risky mortgages. When home prices stopped rising rapidly in 2006-2007, these risky loans began defaulting in large numbers, especially the private label securities not backed by Fannie Mae or Freddie Mac. The crisis was caused by a combination of factors including loose lending, excessive risk taking on Wall Street to generate profits, and a belief that home prices would keep rising indefinitely. More defaults are expected as problem loans continue working their way through the system.
This document summarizes a bio-behavioral surveillance survey of men who have sex with men (MSM) in Serbia in 2010. The key findings were that HIV prevalence was still low among MSM, though risk behaviors like unprotected sex were still common. Condom use increased among MSM who had contact with NGO prevention programs. Strong partnerships between the government and NGOs were found to effectively implement prevention strategies for at-risk groups like MSM. Continued interventions were deemed important to further reduce risky behaviors and HIV transmission among MSM in Serbia.
This document provides templates for business reviews of projects and support activities. It includes templates for overall summaries, project management, risks, finances, and milestones. The templates are organized into sections for general information, projects, and support. Guidance is provided on the intended use and key information for each template to ensure a consistent approach across reviews.
16193713 T2 Partners Presentation On The Mortgage CrisisDavidgantman
This document provides an overview of the ongoing housing and credit crisis and argues that more problems are still to come. It references an investing book about the mortgage meltdown that is currently the #1 bestseller. It also advertises an upcoming value investing conference and subscription newsletters. Two charts show that after decades of stability, housing prices exploded unstably upwards in the 2000s, indicating a bubble.
This document provides an overview of the housing and credit crisis and why more pain is still to come. It summarizes that housing became unaffordable in many areas from 2000-2006 as borrowing power nearly tripled. Mortgage lending standards declined dramatically from 2001-2006, leading to a surge in risky loans. As long as home prices rose, even subprime mortgages performed, but prices falling would cause major losses. Private label mortgages, those securitized by Wall Street, make up 15% of mortgages but 51% of seriously delinquent loans, indicating they are much riskier.
The document summarizes a study that uses strong and weak gravitational lensing to analyze the mass distribution of 28 galaxy clusters. Key findings include:
- The concentration parameter cvir is found to steeply decrease with increasing mass, approximately following cvir ∝ Mvir-0.59±0.12, consistent with theoretical predictions for high-mass clusters but observationally inferred concentrations are higher for lower-mass clusters possibly due to baryon cooling effects.
- Stacking weak lensing shear profiles also supports a steep mass-concentration relation.
- Stacking weak lensing shear maps with position angle information from strong lensing indicates significant ellipticity of the mean mass distribution, with a best-fit ellipticity
Searching for signs_of_triggered_star_formation_toward_ic1848Sérgio Sacani
This document summarizes observations of three bright-rimmed clouds - SFO 11, SFO 11NE, and SFO 11E - associated with the HII region IC 1848, using submillimeter continuum data from SCUBA on the JCMT and molecular line data from CO isotopologues. The observations show evidence for protostellar cores within the clouds and recent or ongoing star formation. Based on the morphology and pressures inferred from the data, it is possible the UV illumination from the primary ionizing star HD17505 has triggered the collapse of dense molecular cores within SFO 11 and SFO 11E.
This document summarizes a study of lithium and sodium abundances in stars in the globular cluster M4. The authors obtained spectra for 91 main sequence and subgiant branch stars using the FLAMES spectrograph on the VLT. They detected a weak anti-correlation between lithium and sodium abundances among unevolved main sequence stars. Notably, one star, #37934, showed an unusually high lithium abundance, comparable to estimates of the primordial lithium abundance. This high lithium abundance, coupled with the star's sodium-rich nature, suggests the lithium may have come from pollution by a previous generation of stars, though preservation of the primordial abundance cannot be ruled out. The detection provides new evidence that globular clusters
1) The document presents new observations of shell structures in the halo of galaxy NGC 7600 and a movie from a cosmological simulation showing how shell galaxies can form in a cold dark matter universe.
2) The movie illustrates how the continuous accretion of dark matter and star clumps creates diffuse circumgalactic structures, and how the disruption of a massive clump on a near-radial orbit creates a complex system of concentric shells resembling those of NGC 7600.
3) With the aid of the simulation, the authors interpret NGC 7600 in the context of the cold dark matter model of galaxy formation through the accretion and disruption of smaller companion galaxies.
Modulations in the_radio_light_curve_of_the_typeiib_supernova_2001igSérgio Sacani
This document summarizes radio observations of the Type IIb supernova SN 2001ig made with the Australia Telescope Compact Array and Very Large Array over 700 days. The observations found periodic deviations from the standard model of radio light curves that are consistent with recurring density modulations in the circumstellar medium with a period of around 150 days. This provides evidence that the progenitor was a Wolf-Rayet star in a binary system with an eccentric 100 day orbit, causing regular build-up of circumstellar material. Such binary systems are thought to produce Type Ib/c supernovae through envelope stripping, linking these events to Type IIb supernovae.
This document presents a study characterizing active galactic nuclei (AGN) selected using mid-infrared colors from the Wide-field Infrared Survey Explorer (WISE). The authors find that a simple color criterion of W1-W2 ≥ 0.8 selects AGN with high reliability to a depth of W2 ∼ 15.0, identifying over 60 AGN candidates per square degree. This WISE selection method is effective at identifying both obscured and unobscured AGN. Using deep data in the COSMOS field, the authors explore the properties and redshift distribution of WISE-selected AGN candidates, finding the selection identifies 78% of AGN identified by previous Spitzer studies.
This study examines the clustering properties and redshift evolution of bias for 593 X-ray selected AGN from the XMM-Newton survey in the COSMOS field with spectroscopic redshifts below z=4. The authors find evidence that the bias factor increases with redshift for the total AGN population, from b=2.30 at z=0.92 to b=4.37 at z=1.94. Splitting the sample, they observe a similar increase in bias with redshift for broad-line and unobscured AGN, corresponding to a constant halo mass of logM~13.28 and logM~13, respectively. The observed bias factors cannot be reproduced by models assuming AGN are triggered
This document summarizes Hubble Space Telescope ultraviolet spectroscopy of four white dwarfs known to accrete planetary debris. The spectra reveal absorption lines from a variety of metals including carbon, oxygen, aluminum, silicon, phosphorus, sulfur, chromium, iron, and nickel. Combined with optical data, between five and eleven different metals are detected in each white dwarf, indicating substantial chemical diversity in the accreted planetary debris. The abundances observed provide insights into the composition and origin of the debris, with some debris resembling bulk Earth composition and others showing evidence of melting and differentiation.
This document is the lecture notes from an introductory astronomy course covering Chapter 15 on galaxies. It provides an overview of the course structure, learning objectives, quiz and exam schedule, and links to additional online resources and images of various galaxies presented in the Astronomy Picture of the Day.
At Akvo's Track Day on 6 March 2012, Luuk and Kathelyne gave a workshop about Akvo's RSR.
In this powerpoint presentation, you'll get a tour of Akvo's admin features in the project back-end.
Weighted logratio biplots provide a method for analyzing compositional data that addresses some limitations of unweighted logratio biplots. The weighted approach introduces row and column masses as weights during centering and fitting, which downplays the influence of rare components with high variance. This weighted logratio biplot, also known as a spectral map, has all the properties of the unweighted biplot as well as the additional property of distributional equivalence. When applied to contingency tables, the weighted logratio biplot/spectral map is comparable to correspondence analysis and may be preferable due to its property of subcompositional coherence. The two methods are nearly identical when the data have low variability.
The document presents preliminary results on daily radiation forecasting using statistical methods. It explores using linear and non-linear prediction techniques like TAG(p) and discusses using historical piranometric data from 1996-2003 to predict daily global solar radiation values and analyze the data through partial autocorrelation. The goals are to characterize and predict solar radiation as an energy resource for applications like short and medium term forecasting.
This document discusses citizen science projects focused on biodiversity in Europe. It provides background on citizen science, describing it as scientific research conducted in whole or in part by amateur or nonprofessional scientists. It then highlights several examples of biodiversity monitoring projects in Europe, including waarnemingen.be, waarneming.nl, observado.org, artportalen.se, and naturgucker.de. These projects engage citizens to record and report observations of taxa in nature. The document compares the scale of these projects in terms of numbers of observations, users, and other collected data.
This document provides an introduction and overview of cloud computing. It discusses the growth and adoption of cloud services, defines key cloud concepts like SaaS, PaaS and IaaS, and highlights some success stories and vendors in the cloud space. It also briefly touches on potential pros and cons of cloud computing.
Natalia Restrepo-Coupe_Remotely-sensed photosynthetic phenology and ecosystem...TERN Australia
This document discusses using remotely sensed data and tower eddy covariance CO2 flux measurements to study phenology and ecosystem productivity. It notes that flux tower data can help validate remote sensing phenology products by determining if they correctly capture dates of green-up, peak growing season, end of season, and season length. The document also aims to better understand what vegetation indices mean quantitatively and their biome-specific relationships to in-situ ecosystem behavior and capacity. Improving this understanding could lead to more robust land surface models informed by remote sensing.
This document summarizes research on achieving high reliability and low-cost lead-free solder joints using manganese or cerium doping of tin-silver-copper (SAC) solder. Experimental results show that SAC doped with 0.05% manganese (SACM) or 0.02% cerium (SACC) outperforms baseline SAC105 and SAC305 alloys in drop test reliability and thermal cycling performance. Specifically, SACM and SACC exhibit higher drop test lifetimes and allow packages to withstand higher dynamic bending strains compared to SAC105 and SAC305. This research demonstrates that minor manganese or cerium doping of SAC alloys can improve
T2 Partners Presentation On The Mortgage Crisismdjonesb
This 3 paragraph document provides an overview of the housing/credit crisis and why there is more pain to come:
1) Housing was stable for the second half of the 20th century but then prices exploded from 2000-2006 as lending standards declined dramatically, allowing homeowners to borrow much more against their homes.
2) As a result, the percentage of equity homeowners had in their homes fell below 50% for the first time, leaving many underwater. Private label mortgages like subprime, which were securitized by Wall Street, made up only 15% of mortgages but account for 51% of seriously delinquent loans.
3) Deregulation led to a surge in profits and compensation
T2 Partners Presentation On The Mortgage Crisisrossreller
This document provides an overview of the housing and credit crisis and why more problems are expected. It summarizes that loose lending standards from 2001-2006 led to a surge in risky mortgages. When home prices stopped rising rapidly in 2006-2007, these risky loans began defaulting in large numbers, especially the private label securities not backed by Fannie Mae or Freddie Mac. The crisis was caused by a combination of factors including loose lending, excessive risk taking on Wall Street to generate profits, and a belief that home prices would keep rising indefinitely. More defaults are expected as problem loans continue working their way through the system.
This document summarizes a bio-behavioral surveillance survey of men who have sex with men (MSM) in Serbia in 2010. The key findings were that HIV prevalence was still low among MSM, though risk behaviors like unprotected sex were still common. Condom use increased among MSM who had contact with NGO prevention programs. Strong partnerships between the government and NGOs were found to effectively implement prevention strategies for at-risk groups like MSM. Continued interventions were deemed important to further reduce risky behaviors and HIV transmission among MSM in Serbia.
This document provides templates for business reviews of projects and support activities. It includes templates for overall summaries, project management, risks, finances, and milestones. The templates are organized into sections for general information, projects, and support. Guidance is provided on the intended use and key information for each template to ensure a consistent approach across reviews.
16193713 T2 Partners Presentation On The Mortgage CrisisDavidgantman
This document provides an overview of the ongoing housing and credit crisis and argues that more problems are still to come. It references an investing book about the mortgage meltdown that is currently the #1 bestseller. It also advertises an upcoming value investing conference and subscription newsletters. Two charts show that after decades of stability, housing prices exploded unstably upwards in the 2000s, indicating a bubble.
This document provides an overview of the housing and credit crisis and why more pain is still to come. It summarizes that housing became unaffordable in many areas from 2000-2006 as borrowing power nearly tripled. Mortgage lending standards declined dramatically from 2001-2006, leading to a surge in risky loans. As long as home prices rose, even subprime mortgages performed, but prices falling would cause major losses. Private label mortgages, those securitized by Wall Street, make up 15% of mortgages but 51% of seriously delinquent loans, indicating they are much riskier.
Compositions of iron-meteorite parent bodies constrainthe structure of the pr...Sérgio Sacani
Magmatic iron-meteorite parent bodies are the earliest planetesimals in the Solar System,and they preserve information about conditions and planet-forming processes in thesolar nebula. In this study, we include comprehensive elemental compositions andfractional-crystallization modeling for iron meteorites from the cores of five differenti-ated asteroids from the inner Solar System. Together with previous results of metalliccores from the outer Solar System, we conclude that asteroidal cores from the outerSolar System have smaller sizes, elevated siderophile-element abundances, and simplercrystallization processes than those from the inner Solar System. These differences arerelated to the formation locations of the parent asteroids because the solar protoplane-tary disk varied in redox conditions, elemental distributions, and dynamics at differentheliocentric distances. Using highly siderophile-element data from iron meteorites, wereconstruct the distribution of calcium-aluminum-rich inclusions (CAIs) across theprotoplanetary disk within the first million years of Solar-System history. CAIs, the firstsolids to condense in the Solar System, formed close to the Sun. They were, however,concentrated within the outer disk and depleted within the inner disk. Future modelsof the structure and evolution of the protoplanetary disk should account for this dis-tribution pattern of CAIs.
Signatures of wave erosion in Titan’s coastsSérgio Sacani
The shorelines of Titan’s hydrocarbon seas trace flooded erosional landforms such as river valleys; however, it isunclear whether coastal erosion has subsequently altered these shorelines. Spacecraft observations and theo-retical models suggest that wind may cause waves to form on Titan’s seas, potentially driving coastal erosion,but the observational evidence of waves is indirect, and the processes affecting shoreline evolution on Titanremain unknown. No widely accepted framework exists for using shoreline morphology to quantitatively dis-cern coastal erosion mechanisms, even on Earth, where the dominant mechanisms are known. We combinelandscape evolution models with measurements of shoreline shape on Earth to characterize how differentcoastal erosion mechanisms affect shoreline morphology. Applying this framework to Titan, we find that theshorelines of Titan’s seas are most consistent with flooded landscapes that subsequently have been eroded bywaves, rather than a uniform erosional process or no coastal erosion, particularly if wave growth saturates atfetch lengths of tens of kilometers.
SDSS1335+0728: The awakening of a ∼ 106M⊙ black hole⋆Sérgio Sacani
Context. The early-type galaxy SDSS J133519.91+072807.4 (hereafter SDSS1335+0728), which had exhibited no prior optical variations during the preceding two decades, began showing significant nuclear variability in the Zwicky Transient Facility (ZTF) alert stream from December 2019 (as ZTF19acnskyy). This variability behaviour, coupled with the host-galaxy properties, suggests that SDSS1335+0728 hosts a ∼ 106M⊙ black hole (BH) that is currently in the process of ‘turning on’. Aims. We present a multi-wavelength photometric analysis and spectroscopic follow-up performed with the aim of better understanding the origin of the nuclear variations detected in SDSS1335+0728. Methods. We used archival photometry (from WISE, 2MASS, SDSS, GALEX, eROSITA) and spectroscopic data (from SDSS and LAMOST) to study the state of SDSS1335+0728 prior to December 2019, and new observations from Swift, SOAR/Goodman, VLT/X-shooter, and Keck/LRIS taken after its turn-on to characterise its current state. We analysed the variability of SDSS1335+0728 in the X-ray/UV/optical/mid-infrared range, modelled its spectral energy distribution prior to and after December 2019, and studied the evolution of its UV/optical spectra. Results. From our multi-wavelength photometric analysis, we find that: (a) since 2021, the UV flux (from Swift/UVOT observations) is four times brighter than the flux reported by GALEX in 2004; (b) since June 2022, the mid-infrared flux has risen more than two times, and the W1−W2 WISE colour has become redder; and (c) since February 2024, the source has begun showing X-ray emission. From our spectroscopic follow-up, we see that (i) the narrow emission line ratios are now consistent with a more energetic ionising continuum; (ii) broad emission lines are not detected; and (iii) the [OIII] line increased its flux ∼ 3.6 years after the first ZTF alert, which implies a relatively compact narrow-line-emitting region. Conclusions. We conclude that the variations observed in SDSS1335+0728 could be either explained by a ∼ 106M⊙ AGN that is just turning on or by an exotic tidal disruption event (TDE). If the former is true, SDSS1335+0728 is one of the strongest cases of an AGNobserved in the process of activating. If the latter were found to be the case, it would correspond to the longest and faintest TDE ever observed (or another class of still unknown nuclear transient). Future observations of SDSS1335+0728 are crucial to further understand its behaviour. Key words. galaxies: active– accretion, accretion discs– galaxies: individual: SDSS J133519.91+072807.4
Discovery of An Apparent Red, High-Velocity Type Ia Supernova at 𝐳 = 2.9 wi...Sérgio Sacani
We present the JWST discovery of SN 2023adsy, a transient object located in a host galaxy JADES-GS
+
53.13485
−
27.82088
with a host spectroscopic redshift of
2.903
±
0.007
. The transient was identified in deep James Webb Space Telescope (JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES) program. Photometric and spectroscopic followup with NIRCam and NIRSpec, respectively, confirm the redshift and yield UV-NIR light-curve, NIR color, and spectroscopic information all consistent with a Type Ia classification. Despite its classification as a likely SN Ia, SN 2023adsy is both fairly red (
�
(
�
−
�
)
∼
0.9
) despite a host galaxy with low-extinction and has a high Ca II velocity (
19
,
000
±
2
,
000
km/s) compared to the general population of SNe Ia. While these characteristics are consistent with some Ca-rich SNe Ia, particularly SN 2016hnk, SN 2023adsy is intrinsically brighter than the low-
�
Ca-rich population. Although such an object is too red for any low-
�
cosmological sample, we apply a fiducial standardization approach to SN 2023adsy and find that the SN 2023adsy luminosity distance measurement is in excellent agreement (
≲
1
�
) with
Λ
CDM. Therefore unlike low-
�
Ca-rich SNe Ia, SN 2023adsy is standardizable and gives no indication that SN Ia standardized luminosities change significantly with redshift. A larger sample of distant SNe Ia is required to determine if SN Ia population characteristics at high-
�
truly diverge from their low-
�
counterparts, and to confirm that standardized luminosities nevertheless remain constant with redshift.
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...Sérgio Sacani
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the R–I spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...Sérgio Sacani
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDSSérgio Sacani
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 M⊙) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10−4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
Anti-Universe And Emergent Gravity and the Dark UniverseSérgio Sacani
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Tr...Sérgio Sacani
Recent discoveries of Earth-sized planets transiting nearby M dwarfs have made it possible to characterize the
atmospheres of terrestrial planets via follow-up spectroscopic observations. However, the number of such planets
receiving low insolation is still small, limiting our ability to understand the diversity of the atmospheric
composition and climates of temperate terrestrial planets. We report the discovery of an Earth-sized planet
transiting the nearby (12 pc) inactive M3.0 dwarf Gliese 12 (TOI-6251) with an orbital period (Porb) of 12.76 days.
The planet, Gliese 12 b, was initially identified as a candidate with an ambiguous Porb from TESS data. We
confirmed the transit signal and Porb using ground-based photometry with MuSCAT2 and MuSCAT3, and
validated the planetary nature of the signal using high-resolution images from Gemini/NIRI and Keck/NIRC2 as
well as radial velocity (RV) measurements from the InfraRed Doppler instrument on the Subaru 8.2 m telescope
and from CARMENES on the CAHA 3.5 m telescope. X-ray observations with XMM-Newton showed the host
star is inactive, with an X-ray-to-bolometric luminosity ratio of log 5.7 L L X bol » - . Joint analysis of the light
curves and RV measurements revealed that Gliese 12 b has a radius of 0.96 ± 0.05 R⊕,a3σ mass upper limit of
3.9 M⊕, and an equilibrium temperature of 315 ± 6 K assuming zero albedo. The transmission spectroscopy metric
(TSM) value of Gliese 12 b is close to the TSM values of the TRAPPIST-1 planets, adding Gliese 12 b to the small
list of potentially terrestrial, temperate planets amenable to atmospheric characterization with JWST.
Gliese 12 b, a temperate Earth-sized planet at 12 parsecs discovered with TES...Sérgio Sacani
We report on the discovery of Gliese 12 b, the nearest transiting temperate, Earth-sized planet found to date. Gliese 12 is a
bright (V = 12.6 mag, K = 7.8 mag) metal-poor M4V star only 12.162 ± 0.005 pc away from the Solar system with one of the
lowest stellar activity levels known for M-dwarfs. A planet candidate was detected by TESS based on only 3 transits in sectors
42, 43, and 57, with an ambiguity in the orbital period due to observational gaps. We performed follow-up transit observations
with CHEOPS and ground-based photometry with MINERVA-Australis, SPECULOOS, and Purple Mountain Observatory,
as well as further TESS observations in sector 70. We statistically validate Gliese 12 b as a planet with an orbital period of
12.76144 ± 0.00006 d and a radius of 1.0 ± 0.1 R⊕, resulting in an equilibrium temperature of ∼315 K. Gliese 12 b has excellent
future prospects for precise mass measurement, which may inform how planetary internal structure is affected by the stellar
compositional environment. Gliese 12 b also represents one of the best targets to study whether Earth-like planets orbiting cool
stars can retain their atmospheres, a crucial step to advance our understanding of habitability on Earth and across the galaxy.
The importance of continents, oceans and plate tectonics for the evolution of...Sérgio Sacani
Within the uncertainties of involved astronomical and biological parameters, the Drake Equation
typically predicts that there should be many exoplanets in our galaxy hosting active, communicative
civilizations (ACCs). These optimistic calculations are however not supported by evidence, which is
often referred to as the Fermi Paradox. Here, we elaborate on this long-standing enigma by showing
the importance of planetary tectonic style for biological evolution. We summarize growing evidence
that a prolonged transition from Mesoproterozoic active single lid tectonics (1.6 to 1.0 Ga) to modern
plate tectonics occurred in the Neoproterozoic Era (1.0 to 0.541 Ga), which dramatically accelerated
emergence and evolution of complex species. We further suggest that both continents and oceans
are required for ACCs because early evolution of simple life must happen in water but late evolution
of advanced life capable of creating technology must happen on land. We resolve the Fermi Paradox
(1) by adding two additional terms to the Drake Equation: foc
(the fraction of habitable exoplanets
with significant continents and oceans) and fpt
(the fraction of habitable exoplanets with significant
continents and oceans that have had plate tectonics operating for at least 0.5 Ga); and (2) by
demonstrating that the product of foc
and fpt
is very small (< 0.00003–0.002). We propose that the lack
of evidence for ACCs reflects the scarcity of long-lived plate tectonics and/or continents and oceans on
exoplanets with primitive life.
A Giant Impact Origin for the First Subduction on EarthSérgio Sacani
Hadean zircons provide a potential record of Earth's earliest subduction 4.3 billion years ago. Itremains enigmatic how subduction could be initiated so soon after the presumably Moon‐forming giant impact(MGI). Earlier studies found an increase in Earth's core‐mantle boundary (CMB) temperature due to theaccumulation of the impactor's core, and our recent work shows Earth's lower mantle remains largely solid, withsome of the impactor's mantle potentially surviving as the large low‐shear velocity provinces (LLSVPs). Here,we show that a hot post‐impact CMB drives the initiation of strong mantle plumes that can induce subductioninitiation ∼200 Myr after the MGI. 2D and 3D thermomechanical computations show that a high CMBtemperature is the primary factor triggering early subduction, with enrichment of heat‐producing elements inLLSVPs as another potential factor. The models link the earliest subduction to the MGI with implications forunderstanding the diverse tectonic regimes of rocky planets.
Climate extremes likely to drive land mammal extinction during next supercont...Sérgio Sacani
Mammals have dominated Earth for approximately 55 Myr thanks to their
adaptations and resilience to warming and cooling during the Cenozoic. All
life will eventually perish in a runaway greenhouse once absorbed solar
radiation exceeds the emission of thermal radiation in several billions of
years. However, conditions rendering the Earth naturally inhospitable to
mammals may develop sooner because of long-term processes linked to
plate tectonics (short-term perturbations are not considered here). In
~250 Myr, all continents will converge to form Earth’s next supercontinent,
Pangea Ultima. A natural consequence of the creation and decay of Pangea
Ultima will be extremes in pCO2 due to changes in volcanic rifting and
outgassing. Here we show that increased pCO2, solar energy (F⨀;
approximately +2.5% W m−2 greater than today) and continentality (larger
range in temperatures away from the ocean) lead to increasing warming
hostile to mammalian life. We assess their impact on mammalian
physiological limits (dry bulb, wet bulb and Humidex heat stress indicators)
as well as a planetary habitability index. Given mammals’ continued survival,
predicted background pCO2 levels of 410–816 ppm combined with increased
F⨀ will probably lead to a climate tipping point and their mass extinction.
The results also highlight how global landmass configuration, pCO2 and F⨀
play a critical role in planetary habitability.
Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
Monitoring and Managing Anomaly Detection on OpenShift
Overview
Dive into the world of anomaly detection on edge devices with our comprehensive hands-on tutorial. This SlideShare presentation will guide you through the entire process, from data collection and model training to edge deployment and real-time monitoring. Perfect for those looking to implement robust anomaly detection systems on resource-constrained IoT/edge devices.
Key Topics Covered
1. Introduction to Anomaly Detection
- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
- Step-by-step guide on deploying anomaly detection models on edge devices using ArgoCD.
5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
5th LF Energy Power Grid Model Meet-up SlidesDanBrown980551
5th Power Grid Model Meet-up
It is with great pleasure that we extend to you an invitation to the 5th Power Grid Model Meet-up, scheduled for 6th June 2024. This event will adopt a hybrid format, allowing participants to join us either through an online Mircosoft Teams session or in person at TU/e located at Den Dolech 2, Eindhoven, Netherlands. The meet-up will be hosted by Eindhoven University of Technology (TU/e), a research university specializing in engineering science & technology.
Power Grid Model
The global energy transition is placing new and unprecedented demands on Distribution System Operators (DSOs). Alongside upgrades to grid capacity, processes such as digitization, capacity optimization, and congestion management are becoming vital for delivering reliable services.
Power Grid Model is an open source project from Linux Foundation Energy and provides a calculation engine that is increasingly essential for DSOs. It offers a standards-based foundation enabling real-time power systems analysis, simulations of electrical power grids, and sophisticated what-if analysis. In addition, it enables in-depth studies and analysis of the electrical power grid’s behavior and performance. This comprehensive model incorporates essential factors such as power generation capacity, electrical losses, voltage levels, power flows, and system stability.
Power Grid Model is currently being applied in a wide variety of use cases, including grid planning, expansion, reliability, and congestion studies. It can also help in analyzing the impact of renewable energy integration, assessing the effects of disturbances or faults, and developing strategies for grid control and optimization.
What to expect
For the upcoming meetup we are organizing, we have an exciting lineup of activities planned:
-Insightful presentations covering two practical applications of the Power Grid Model.
-An update on the latest advancements in Power Grid -Model technology during the first and second quarters of 2024.
-An interactive brainstorming session to discuss and propose new feature requests.
-An opportunity to connect with fellow Power Grid Model enthusiasts and users.
Freshworks Rethinks NoSQL for Rapid Scaling & Cost-EfficiencyScyllaDB
Freshworks creates AI-boosted business software that helps employees work more efficiently and effectively. Managing data across multiple RDBMS and NoSQL databases was already a challenge at their current scale. To prepare for 10X growth, they knew it was time to rethink their database strategy. Learn how they architected a solution that would simplify scaling while keeping costs under control.
FREE A4 Cyber Security Awareness Posters-Social Engineering part 3Data Hops
Free A4 downloadable and printable Cyber Security, Social Engineering Safety and security Training Posters . Promote security awareness in the home or workplace. Lock them Out From training providers datahops.com
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
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Giant blob eso
1. Central Powering of the Largest Lyman-alpha Nebula is Re-
vealed by Polarized Radiation
Matthew Hayes1,2,3 , Claudia Scarlata4,5 , and Brian Siana6
1
Universit´ de Toulouse, UPS-OMP; IRAP; Toulouse, France
e
2
CNRS; IRAP; 14, avenue Edouard Belin, F-31400 Toulouse, France
3
Observatory of Geneva, University of Geneva, 51 ch. des Maillettes, 1290 Versoix, Switzerland
4
Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota,
Minneapolis, MN 55455, USA
5
Spitzer Science Center, California Institute of Technology, 220-6, Pasadena, CA 91125, USA
6
Department of Astronomy, California Institute of Technology, MS 249-17, Pasadena, CA 91125,
USA
High-redshift Lyman-alpha blobs1, 2 are extended, luminous, but rare structures that appear
to be associated with the highest peaks in the matter density of the Universe3–6 . Their en-
ergy output and morphology are similar to powerful radio galaxies7 , but the source of the
luminosity is unclear. Some blobs are associated with ultraviolet or infrared bright galaxies,
suggesting an extreme starburst event or accretion onto a central black hole8–10 . Another
possibility is gas that is shock excited by supernovae11, 12 . However some blobs are not associ-
ated with galaxies13, 14 , and may instead be heated by gas falling into a dark matter halo15–19 .
The polarization of the Lyα emission can in principle distinguish between these options20–22 ,
but a previous attempt to detect this signature returned a null detection23 . Here we report
on the detection of polarized Lyα from the blob LAB12 . Although the central region shows
no measurable polarization, the polarized fraction (P) increases to ≈ 20 per cent at a radius
of 45 kpc, forming an almost complete polarized ring. The detection of polarized radiation
is inconsistent with the in situ production of Lyα photons, and we conclude that they must
have been produced in the galaxies hosted within the nebula, and re-scattered by neutral
hydrogen.
The Lyα emission line of neutral hydrogen is a frequently used observational tracer of evolv-
ing galaxies in the high redshift Universe. Lyα imaging surveys typically find a large number
of faint unresolved objects and a small fraction of extremely luminous and spatially extended sys-
tems that are usually referred to independently as Lyman alpha blobs (LABs). The compact sources
usually appear to be more ordinary star forming galaxies whereas, since their discovery, much con-
troversy has surrounded the true nature of LABs. Because one of the possible modes of powering
LABs is the accretion of gas from the intergalactic medium15–19 , an eventual consensus about this
powering mechanism holds particular relevance for how the most massive and rapidly evolving
high redshift dark matter haloes acquire the gas required to fuel star formation in the galaxies they
host. Predictions for polarized Lyα radiation were made over a decade ago20 , and have been further
developed to the extent that the polarization signal may act as a diagnostic to study the origin of
the Lyα photons21 . By relying upon the scattering of Lyα photons at large distances from their
1
2. production sites, these polarization measurements may also provide an independent constraint on
the distribution of neutral gas in the circumgalactic regions, which has proven a difficult measure-
ment to make by traditional techniques. The one previous attempt to detect the polarization of a
LAB returned a null result23 , although very deep observations are required that need considerable
time investments on 8–10 meter class telescopes. In the ESO Very Large Telescope observations
presented here, we observe one of the largest and most luminous LABs on the sky in imaging
polarimetry mode (Figs 1 and 2).
ext
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Figure 1 | LAB1 in Lyα. The large panel to the left shows the combined intensity frame that
has been adaptively smoothed in order to show detail. The Lyα emission is spatially extended
over scales of more than 10 arcsec (80 kpc). The 5 arcsecond scale bar shown in the left panel
corresponds to 40 physical kilo-parsec. North is up and East is to the left. The primary target
of this observation is LAB1 2 , although the position angle was chosen so as to also include
LAB8 4 , which resides some 20 arcsec to the North. The bright point source to the South East
(lower right) is the AGN C112 . Major centres are labelled in the image. The two smaller frames
to the right show the ordinary and extraordinary beams (lower and upper, respectively), which
have been tessellated for quantitative analysis (Supplementary Information). All images are
shown on the same intensity scaling, and even by eye differences in the intensity structure
between the two beams become visible. The cross marks the point that we determine to be
the centre in the subsequent analysis, and is determined as the point of peak Lyα surface
brightness that is not associated with the AGN.
These new, deep polarimetric observations show a substantial fraction of the Lyα emission
2
3. from LAB1 to be polarized. The data enable the fraction of light that is linearly polarized (P) to
be measured to better than 5% (r.m.s.) in the regions of peak surface brightness, however in these
central regions we find essentially no polarization signal. In order to detect the polarized emission
we need to examine the fainter signal emanating a few arcsec from the centre – when Lyα is emitted
with a high polarization fraction (P ≈ 20%), it is not spatially coincident with the brighter regions
of the nebula. Indeed the highest and most statistically certain measures of P are found some
4–8 arcsec from the centre, forming an almost complete ring of polarized emission. Just a single
resolution element shows a signal-to-noise ratio on P that exceeds 3, but our confidence in these
results is substantially enhanced by the strong degree of spatial correlation between the resolution
elements that are observed to be polarized at high significance. Away from the regions of bright
Lyα emission our data show no measurable polarization signal, but a second nearby extended Lyα
source (LAB84 ) that lies to the north also shows strongly polarized Lyα.
Lyα is a resonant line and photons scatter in neutral hydrogen (H i), undergoing a com-
plicated radiation transfer. At each scattering event, of which there may be millions, a photon
acquires a new direction and frequency, dependent upon the kinematics of the scattering medium
and quantum mechanical probabilities24 . The outgoing frequency determines the optical depth that
the photon then sees25, 26 : small shifts from line-centre (core scatterings) result in effectively no
transfer, while long frequency excursions (wing scatterings) result in significant flights and likely
escape from the system. The more frequent core scatterings may emit polarized radiation but it is
typically with a low fraction (P 7%); the comparatively rare wing scatterings, on the other hand,
may introduce a high degree of linear polarization to the outgoing radiation (P up to 40%)21, 24 . The
observed polarization signal therefore provides an unambiguous signature of the scattering nature
of the diffuse Lyα halos, and distribution of circumgalactic gas. On the atomic level, the detected
polarization signal provides evidence that the Lyα photons are not emerging after a large number
of resonant core scattering events, but are exiting after long shifts in frequency.
The detection of polarization demonstrates that the Lyα photons cannot have been produced
in situ at large radial distances. In order to impart a significant level of polarization on the outgoing
radiation, a geometry is required in which Lyα photons preferentially escape after scattering off hy-
drogen atoms at angles of 90 degrees to their vector prior to the scattering event21, 24 . This geometry
is not expected in the case of wind/shock excitation since thermalized cooling gas will generate
Lyα photons with no preferential orientation or impact angle with respect to the scattering medium.
Similarly, the filamentary streams of cold infalling gas predicted by simulation27, 28 appear to have
too small volume filling factors, and be too narrow (few kpc) for any imparted polarization signal
to be observable17 – a spatial resolution would be required that is currently unattainable by optical
polarimeters. While neither of these rejected scenarios have yet been thoroughly tested by radia-
tive transport studies, the production of polarized Lyα is well understood, and it is difficult to see a
mechanism by which observably polarized Lyα may be produced in these situations. We therefore
conclude that the Lyα photons must have been produced centrally in the galaxies themselves and
scattered at large radii by neutral gas. Even if the halo is accreting intergalactic gas, this process is
not responsible for a large fraction of the Lyα emission.
3
4. Stokes Q 2σ error P @ conf > 2σ
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Right ascension [ degrees ] Right ascension [ degrees ] Right ascension [ degrees ]
Figure 2 | The polarization of LAB1. Scaling is shown to the right of each panel. Panels
(a) and (b) show the Q and U Stokes parameters. Panel (c) shows a map of the polarization
fraction P that we can measure at 95.4% confidence; this error map demonstrates that in
individual resolution elements we can constrain P in the central regions down to 10% (2σ). At
a radius of ≈ 6 − 7 arcsec, this decreases to about the 20% level, and beyond ≈ 10 arcsec
P becomes noise-dominated. Panel (d) shows the value of P in resolution elements where
it can be well constrained; we make a cut based on the error map, and show bins where P
can be measured to better than 16% (2σ). P of around 5–10% is found in the centre, but
increases to 15–20% at ≈ 5 arcsec from the centre towards the South, West, and North edges
of LAB1. P ≈ 20% is also seen around LAB8. Panel (e) shows P in bins for which we can be
at least 95.4% confident of its measurement. The structure around LAB1 and LAB8 remains,
extending to larger radii, and forming a broken ring at P ∼ 20%. Panel (f) shows a smoothed
intensity image with the direction of the polarization vector, χ, shown by red bars. As with panel
(e) only bins showing measurements at more than 95.4% confidence level are shown. There is
a clear trend that, when bins show strong polarization, they orientate themselves tangentially
to the overall structure and local Lyα surface brightness. These features conform well with the
predictions for the polarization of Lyα photons that are centrally produced and scatter at large
radii, or are produced by cooling gas that flows onto the dark matter halo in quasi spherical
symmetry 21 .
The geometrical origin of the polarization signal in the photon scattering model, which is
analogous to Rayleigh scattering, implies also that the angle of the polarization vector χ should
align tangentially to the overall geometry of the system at large radii21, 22 . We also extract this χ
vector from the data (Fig 2, panel f). If we define the geometric centre to be the region of peak Lyα
surface brightness (excluding the active nucleus; Fig 1), these vectors display a strong tendency to
4
5. orientate along directions tangential to the overall geometry of the system. Again this is in good
agreement with theoretical expectations, should the Lyα photons be produced centrally by ordinary
star-formation and/or AGN-fueled processes and scatter at large radii21 . However unlike the ide-
alized models used for radiative transport simulations, which assume perfect spherical symmetry
and no velocity shear or clumping of the gas, the true Lyα surface brightness is far from smooth
and symmetric. This may reflect either multiple Lyα sources within the halo, large scale inhomo-
geneities in the scattering medium, or both. Polarization of Lyα emission in a clumpy medium has
not yet been tested by simulation although clumping could potentially either suppress or enhance
the polarization21 , and likely depends on the relative size and volume filling factor of the clumps.
Regardless, we would still expect the polarization signature to remain provided that the individual
regions are well resolved, in which case χ would then be expected to align tangentially to contours
in the local surface brightness. This effect is also reflected in the data, and we find polarization
vectors preferentially line up at angles approximately perpendicular to the local surface brightness
gradient at their position. The Supplementary Information includes a quantitative analysis of the
polarization angles compared with both local surface brightness gradients and the overall system
geometry.
There is one final observable prediction that has been suggested by radiative transport simu-
lations. This is the radial profile of the polarization fraction, P, which according to the scattering
shell model should present with P ≈ 0 in the geometric centre and increase with increasing radius.
We have computed this radial profile of P using the same central coordinates as defined previously
(Fig 3) and find strong evidence for P increasing with radius, again in agreement with predictions.
The central point on the profile and most significantly polarized point in the ring are discrepant
at over 2σ. We have fitted the innermost 7 arcsec (5 data points; where data are deemed reliable)
with the simplest function for P varying linearly with radius. Computing the classical p−value,
1 − Γ(ν/2, χ2 /2) where ν is the number of degrees of freedom, shows above 96% confidence in this
hypothesis. The same test performed on a flat profile (P = 8.3%), suggests that a structure in which
P is independent of radius is consistent with the data at 16%. Regardless, the slim possibility of P
that is flat with radius does not present a difficulty for the scattering scenario, which is supported
not only by the detection of polarized Lyα itself, but also by the angular distribution of polarization
vectors; this radial profile is simply the least robust of our constraints. The actual gradient of P
with radius depends upon both the column density and radius of the shell, neither of which we
know – assuming that the idealized geometry holds and that the shell has a radius of 10 arcsec, the
models with column densities of 1019 − 1020 cm−2 would be in agreement with the data (Fig 3). In
this step of the analysis we also compute the total luminosity-weighted polarization fraction within
each radius: within 7 arcsec we obtain an integrated value of P = 11.9 ± 2%. We take this value as
the overall polarization fraction of the nebula, which we quote at 6σ significance.
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6. Physical distance [ kpc ]
0 20 40 60 80
Intensity, I
0.4
Fraction, P
Radial binning pattern
6
0.3
21
0.
Signal
4
Declination [ degrees ]
21
0.2
0.
2
21
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0.
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21
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0.0 5”
8
5
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33
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33
1 Right ascension [ degrees ]
0
0 2 4 6 8 10 12
Angular distance [ arcsec ]
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been corrected for spuriously high polarization fractions that may be measured at low signal-
to-noise29 . In magenta the total intensity profile is shown. Errorbars on both measurements
are 1σ, and the lower profile shows the signal-to-noise ratio of P. In the central regions where
intensity is highest, P is measured at ∼ 4%, although at 1σ is consistent with no polarization.
P and its signal-to-noise both increase with radius; by 5 arcsec P = 10% and is inconsistent
with zero at the 4σ level. P peaks at 18% at 7 arcsec, beyond which radius the noise becomes
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curves have been smoothed over lengths of 1.5 arcsec to match our annuli. The actual radius
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in order to approximately match both the surface brightness and polarization profiles. This
shows that the predictions are qualitatively matched by observation. Models for scattering
in a static IGM and spherically symmetric accretion are not show since they are not leading
explanations for the powering of LABs.
6
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Acknowledgements Based on observations made with ESO Telescopes at the Paranal Observatory under
programme ID 084.A-0954. M.H. was supported in part by the Swiss National Science Foundation, and
also received support from Agence Nationale de la recherche bearing the reference ANR-09-BLAN-0234-
01. Patrick Ogle is thanked for his valuable suggestions about polarimetric observations. We are indebted
to Nino Panagia and Terry Jones for comments on the manuscript, and to Daniel Schaerer, Nick Scoville,
Chris Lidman, Arjun Dey, Moire Prescott, and Paul Lynam for discussions.
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9. Author Contributions All authors contributed to the proposal preparation. M.H. and C.S. observed and
reduced the data. M.H. analyzed the results. All authors contributed to the manuscript preparation.
Competing Interests The authors declare that they have no competing financial interests.
Correspondence Correspondence and requests for materials should be addressed to M.H.
(email: matthew.hayes@ast.obs-mip.fr).
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