Conference poster : Morphometry of galaxies: Asymmetry
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1. The document presents a study of rotational asymmetry in galaxies for both morphological and physical diagnostic purposes. It introduces two measures of asymmetry: A1, the existing measure, and A3, an alternative measure proposed using Spearman's correlation coefficient. 2. Methods describe existing measures of concentration, asymmetry, smoothness, and other morphological parameters. It then provides the equations for measuring A1 and introduces A3. 3. Results show correlations between A3 and concentration, and histograms comparing A1 and A3 in distinguishing galaxy types using a sample from existing galaxy catalogs. A3 proved more effective than A1 at distinguishing classes.
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The document discusses group theory and its applications in physics. It begins by introducing symmetry groups that are important in physics, including translations, rotations, and Lorentz transformations. It then discusses the use of group theory in formulating fundamental forces and the Standard Model of particle physics. The document provides definitions of group theory concepts like groups, operations, identity, and inverse. It explains how group theory provides a mathematical framework for describing physical symmetries.
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GPS data is used to calculate strain and rotation rates in three continental plateaus: Tibet, Anatolia, and the Altiplano. For Tibet and Anatolia, the results show large regions of quasi-rigid body rotation bounded by strike-slip faults, with positive dilatation on the outboard sides. The Altiplano has higher internal shortening and negative dilatation everywhere. Vertical axis rotation changes sign across its topographic symmetry axis. Comparing the GPS and geological data provides insights into how interseismic and permanent deformation relate in each region over time.
Photometry of Giant Propellers in Saturn's Rings
1) The document discusses analyzing images of "giant propellers" in Saturn's rings taken by Cassini during its Ring Grazing Orbit and Grand Finale.
2) The authors use images of the propeller "Santos-Dumont" taken on the lit and unlit sides to investigate how the propeller's brightness relates to its optical depth, by comparing predicted and observed brightness values.
3) They find the brightness ratio between prediction and observation is consistent in translucent parts of the propeller and ring, but varies more in opaque parts, helping evaluate differences between empty and opaque regions.
Spectroscopic confirmation of_the_existence_of_large_diffuse_galaxies_in_the_...
Artigo descreve como uma equipe de astrônomos usou o telescópio Keck I para confirmar a existência das Galáxias Ultra Difusas, ou UDGs no Universo.
Gaussian Orbital Determination of 1943 Anteros
Paper detailing the theory, methods, calculations, and results regarding the investigation of the orbit of asteroid 1943 Anteros through approximately six weeks of celestial observation and data collection.
Arthur Weglein's Seismic Imaging & Inversion Book - Volume 1 Review
Volume 1 Review of the Arthur B. Weglein's book publication - "Seismic Imaging & Inversion" , research publication on the seismic data
Detection of solar_like_oscillations_in_relies_of_the_milk_way_asteroseismolo...
Asteroseismic constraints on K giants make it possible to infer radii, masses and ages of tens
of thousands of field stars. Tests against independent estimates of these properties are however
scarce, especially in the metal-poor regime. Here, we report the detection of solar-like
oscillations in 8 stars belonging to the red-giant branch and red-horizontal branch of the globular
cluster M4. The detections were made in photometric observations from the K2 Mission
during its Campaign 2. Making use of independent constraints on the distance, we estimate
masses of the 8 stars by utilising different combinations of seismic and non-seismic inputs.
When introducing a correction to the Δν scaling relation as suggested by stellar models, for
RGB stars we find excellent agreement with the expected masses from isochrone fitting, and
with a distance modulus derived using independent methods. The offset with respect to independent
masses is lower, or comparable with, the uncertainties on the average RGB mass
(4 − 10%, depending on the combination of constraints used). Our results lend confidence to
asteroseismic masses in the metal poor regime. We note that a larger sample will be needed
to allow more stringent tests to be made of systematic uncertainties in all the observables
(both seismic and non-seismic), and to explore the properties of RHB stars, and of different
populations in the cluster.
Ap physics course objectives 2009 official
This document lists learning objectives for AP Physics courses. It covers objectives in five major content areas: Newtonian mechanics, work, energy and power, systems of particles and linear momentum, circular motion and rotation, and electric and magnetic fields. The objectives describe essential concepts and skills students should understand, such as kinematics, Newton's laws of motion, work-energy theorem, conservation of energy, impulse and momentum, uniform circular motion, and more. The objectives are used to guide the content of the AP Physics exams.
TH1.L09 - INVESTIGATIONS ON TOPS INTERFEROMETRY WITH TERRASAR-X
The document discusses techniques for interferometry using TerraSAR-X data acquired in TOPS mode. Two approaches are suggested to estimate constant azimuth offsets between bursts using spectral diversity: 1) Using spectral bands within bursts. 2) Using the overlapping area between bursts. Experimental results with TerraSAR-X data validate these approaches and compare TOPS to ScanSAR and stripmap modes. TOPS-stripmap interferograms seem feasible under a persistent scatterer approach with additional processing needed if there is an azimuth displacement.
CLIM: Transition Workshop - Metrics for Evaluating Sea Ice Models - Yawen Gua...
CLIM: Transition Workshop - Metrics for Evaluating Sea Ice Models - Yawen Gua...The Statistical and Applied Mathematical Sciences Institute
Sea ice models governed by physical equations have been used to simulate the state of the ice including features such as ice thickness, concentration, and motion. Recent satellite observations with high spatio-temporal resolution have also provided unique opportunities to examine ice motion and deformation. These multiple disparate data sources prompted the research questions in our working group: How do we evaluate the skill of models in simulating ice features? How
do we identify numerical model parameter space that produces realistic state of the ice? I will discuss an ongoing project that explores some potential methods for validating sea ice models. Problem 1 a ph o 4
The document is a summary of problems from a physics olympiad competition involving satellite orbit transfers. It asks the examinee to:
1) Calculate the speed of a satellite in a circular orbit around Earth given its mass and orbital radius.
2) Determine the velocity needed to transfer the satellite to a higher orbit passing through point P.
3) Derive the minimum velocity needed for the satellite to escape Earth's gravity completely.
Using the inclinations_of_kepler_systems_to_prioritize_new_titius_bode_based_...
Artigo descreve como cientistas aplicaram a relação de Titius-Bode nos dados do Kepler para prever a existência de bilhões de exoplanetas parecidos com a Terra na Via Láctea.
Stellar variability in_open_clusters_new_class_in_ngc3766
This document summarizes the analysis of periodic variable stars in the open cluster NGC 3766 based on a 7-year monitoring campaign. The authors detected a new class of 36 variable stars located between the instability strips for slowly pulsating B stars and delta Scuti stars, where no variability was previously predicted. The majority of these new variables have periods between 0.1-0.7 days and amplitudes of 1-4 millimagnitudes. The properties of this new class are discussed and the authors argue they are likely pulsating variables sustained by stellar rotation. Additionally, the authors identify other periodic variables such as eclipsing binaries, slowly pulsating B stars, delta Scuti stars, and gamma Doradus candidates.
Tem
The document discusses using transient electromagnetic (TEM) data to correct for static shifts in magnetotelluric (MT) data. TEM data is less sensitive to near-surface heterogeneities and topography, which can cause vertical shifts in MT apparent resistivity curves. The document proposes converting TEM time-domain data to the frequency domain using modeling or time shifting, and shifting the MT data to match the TEM-derived data to correct for static effects. This allows 1D MT modeling techniques to be applied to TEM data as well.
Öncel Akademi: İstatistiksel Sismoloji
This paper proposes a maximum likelihood estimation method for determining the parameters of a modified Gutenberg-Richter magnitude-frequency relation proposed by Lomnitz-Adler and Lomnitz. The relation is a double exponential function with parameters a and B. The maximum likelihood method provides equations that allow iterative determination of parameter a from earthquake catalog data. Parameter B can then be estimated from the data and value of a. The method is demonstrated on a Chinese earthquake catalog, obtaining values of a = 0.10 and B = 10.34.
What's hot (19)
Discovery of rotational modulations in the planetary mass companion 2m1207b i...
Discovery of rotational modulations in the planetary mass companion 2m1207b i...
Riemannian Laplacian Formulation in Oblate Spheroidal Coordinate System Using...
Riemannian Laplacian Formulation in Oblate Spheroidal Coordinate System Using...
Spectroscopic confirmation of_the_existence_of_large_diffuse_galaxies_in_the_...
Spectroscopic confirmation of_the_existence_of_large_diffuse_galaxies_in_the_...
Arthur Weglein's Seismic Imaging & Inversion Book - Volume 1 Review
Arthur Weglein's Seismic Imaging & Inversion Book - Volume 1 Review
Detection of solar_like_oscillations_in_relies_of_the_milk_way_asteroseismolo...
Detection of solar_like_oscillations_in_relies_of_the_milk_way_asteroseismolo...
TH1.L09 - INVESTIGATIONS ON TOPS INTERFEROMETRY WITH TERRASAR-X
TH1.L09 - INVESTIGATIONS ON TOPS INTERFEROMETRY WITH TERRASAR-X
CLIM: Transition Workshop - Metrics for Evaluating Sea Ice Models - Yawen Gua...
CLIM: Transition Workshop - Metrics for Evaluating Sea Ice Models - Yawen Gua...
Using the inclinations_of_kepler_systems_to_prioritize_new_titius_bode_based_...
Using the inclinations_of_kepler_systems_to_prioritize_new_titius_bode_based_...
Stellar variability in_open_clusters_new_class_in_ngc3766
Stellar variability in_open_clusters_new_class_in_ngc3766
Similar to Conference poster : Morphometry of galaxies: Asymmetry
Locating Hidden Exoplanets in ALMA Data Using Machine Learning
Exoplanets in protoplanetary disks cause localized deviations from Keplerian velocity in channel
maps of molecular line emission. Current methods of characterizing these deviations are time consuming, and there is no unified standard approach. We demonstrate that machine learning can quickly
and accurately detect the presence of planets. We train our model on synthetic images generated from
simulations and apply it to real observations to identify forming planets in real systems. Machine
learning methods, based on computer vision, are not only capable of correctly identifying the presence
of one or more planets, but they can also correctly constrain the location of those planets.
High resolution alma_observations_of_sdp81_the_innermost_mass_profile_of_the_...
A Campanha de Linha de Base Longa do ALMA produziu uma imagem muito detalhada de uma galáxia distante afetada por lente gravitacional. A imagem mostra uma vista ampliada das regiões de formação estelar na galáxia, com um nível de detalhe nunca antes alcançado numa galáxia tão remota. As novas observações são muito mais detalhadas do que as obtidas pelo Telescópio Espacial Hubble da NASA/ESA e revelam regiões de formação estelar na galáxia equivalentes a versões gigantes da Nebulosa de Orion.
A Campanha de Linha de Base Longa do ALMA produziu algumas observações extraordinárias e coletou informação com um detalhe sem precedentes dos habitantes do Universo próximo e longínquo. Foram feitas observações no final de 2014 no âmbito de uma campanha que pretendeu estudar uma galáxia distante chamada HATLAS J090311.6+003906, também conhecida pelo nome mais simples de SDP.81. A radiação emitida por esta galáxia é “vítima” de um efeito cósmico chamado lente gravitacional. Uma galáxia enorme que se situa entre SDP.81 e o ALMA [1] atua como lente gravitacional, distorcendo a radiação emitida pela galáxia mais distante e criando um exemplo quase perfeito do fenômeno conhecido por Anel de Einstein [2].
Pelo menos sete grupos de cientistas [3] analisaram de forma independente os dados do ALMA sobre SDP.81. Esta profusão de artigos científicos deu-nos informação sem precedentes sobre esta galáxia, revelando detalhes sobre a sua estrutura, conteúdo, movimento e outras características físicas.
O ALMA funciona como um interferômetro, isto é, a rede múltipla de antenas trabalha em sintonia perfeita coletando radiação como se de um único e enorme telescópio virtual se tratasse [4]. Como resultado, estas novas imagens de SDP.81 possuem uma resolução até 6 vezes melhor [5] que as imagens obtidas no infravermelho com o Telescópio Espacial Hubble da NASA/ESA.
SPECTROSCOPIC CONFIRMATION OF THE EXISTENCE OF LARGE, DIFFUSE GALAXIES IN THE...
We recently identified a population of low surface brightness objects in the field of the z = 0.023 Coma cluster,
using the Dragonfly Telephoto Array. Here we present Keck spectroscopy of one of the largest of these “ultradiffuse
galaxies” (UDGs), confirming that it is a member of the cluster. The galaxy has prominent absorption
features, including the Ca II H+K lines and the G-band, and no detected emission lines. Its radial velocity of
cz=6280±120 km s−1 is within the 1σ velocity dispersion of the Coma cluster. The galaxy has an effective
radius of 4.3 ± 0.3 kpc and a Sérsic index of 0.89 ± 0.06, as measured from Keck imaging. We find no indications
of tidal tails or other distortions, at least out to a radius of ∼2re. We show that UDGs are located in a previously
sparsely populated region of the size—magnitude plane of quiescent stellar systems, as they are ∼6 mag fainter
than normal early-type galaxies of the same size. It appears that the luminosity distribution of large quiescent
galaxies is not continuous, although this could largely be due to selection effects. Dynamical measurements are
needed to determine whether the dark matter halos of UDGs are similar to those of galaxies with the same
luminosity or to those of galaxies with the same size.
Optical proper motion_measurements_of_the_m87_jet_new_results_from_the_hubble...
This document summarizes new results from a study of proper motions in the optical jet of the galaxy M87 using over 13 years of Hubble Space Telescope imaging data. Key findings include:
1) Superluminal velocities (above the speed of light) were measured for knots as far out as knot C in the jet, suggesting these speeds persist over large distances.
2) Significant apparent accelerations both parallel and transverse to the jet axis were found, as well as evidence for stationary features in some knots.
3) Complex motions including differing velocities between nearby features and changes in velocity over time were observed throughout the jet, placing constraints on theoretical jet models.
The build up_of_the_c_d_halo_of_m87_evidence_for_accretion_in_the_last_gyr
Observações recentes obtidas com o Very Large Telescope do ESO mostraram que Messier 87, a galáxia elíptica gigante mais próximo de nós, engoliu uma galáxia inteira de tamanho médio no último bilhão de anos. Uma equipe de astrônomos conseguiu pela primeira vez seguir o movimento de 300 nebulosas planetárias brilhantes, encontrando evidências claras deste evento e encontrando também excesso de radiação emitida pelos restos da vítima completamente desfeita.
IVega_Acevedo
This document discusses the asymmetry and star formation rate of dwarf spiral galaxies. It analyzes the asymmetry parameter (A) and star formation rate (SFR) values of 9 dwarf spiral galaxies using CAS morphological parameters and H-alpha emission fluxes. A positive correlation was found between A and SFR, with SFR increasing linearly with A. The conclusions note some galaxies had unusual Sersic indices possibly related to bars, and that A and SFR were generally correlated for these dwarf spiral galaxies.
The canarias einstein_ring_a_newly_discovered_optical_einstein_ring
This document reports the discovery of a newly discovered optical Einstein ring (ER) called the "Canarias Einstein Ring". It was discovered serendipitously in imaging data from the Dark Energy Camera. Follow-up spectroscopy with the Gran Telescopio CANARIAS confirmed the nature of the system, with the lens being an early-type galaxy at a redshift of z=0.581 and the source being a starburst galaxy at z=1.165. Analysis of the system determined the Einstein radius to be 2.16 arcseconds and the total enclosed mass producing the lensing effect to be 1.86 ± 0.23 × 1012 solar masses.
The atacama cosmology_telescope_measuring_radio_galaxy_bias_through_cross_cor...
A radiação cósmica de micro-ondas aponta para a matéria escura invisível, marcando o ponto onde jatos de material viajam a velocidades próximas da velocidade da luz, de acordo com uma equipe internacional de astrônomos. O principal autor do estudo, Rupert Allison da Universidade de Oxford apresentou os resultados no dia 6 de Julho de 2015 no National Astronomy Meeting em Venue Cymru, em Llandudno em Wales.
Atualmente, ninguém sabe ao certo do que a matéria escura é feita, mas ela é responsável por cerca de 26% do conteúdo de energia do universo, com galáxias massivas se formando em densas regiões de matéria escura. Embora invisível, a matéria escura se mostra através do efeito gravitacional – uma grande bolha de matéria escura puxa a matéria normal (como elétrons, prótons e nêutrons) através de sua própria gravidade, eventualmente se empacotando conjuntamente para criar as estrelas e galáxias inteiras.
Muitas das maiores dessas são galáxias ativas com buracos negros supermassivos em seus centros. Alguma parte do gás caindo diretamente na direção do buraco negro é ejetada como jatos de partículas e radiação. As observações feitas com rádio telescópios mostram que esses jatos as vezes se espalham por milhões de anos-luz desde a galáxia – mais distante até mesmo do que a extensão da própria galáxia.
Os cientistas esperam que os jatos possam viver em regiões onde existe um excesso de concentração da matéria escura, maior do que o da média. Mas como a matéria escura é invisível, testar essa ideia não é algo tão direto.
Signal Synchronization Strategies and Time Domain SETI with Gaia DR3
Spatiotemporal techniques for signal coordination with actively transmitting extraterrestrial civilizations, without the need for prior communication, can constrain technosignature searches to a significantly smaller coordinate space. With the variable star
catalog from Gaia Data Release 3, we explore two related signaling strategies: the SETI
Ellipsoid, and that proposed by Seto, which are both based on the synchronization of
transmissions with a conspicuous astrophysical event. This dataset contains more than
10 million variable star candidates with light curves from the first three years of Gaia’s
operational phase, between 2014 and 2017. Using four different historical supernovae as
source events, we find that less than 0.01% of stars in the sample have crossing times,
the times at which we would expect to receive synchronized signals on Earth, within
the date range of available Gaia observations. For these stars, we present a framework
for technosignature analysis that searches for modulations in the variability parameters
by splitting the stellar light curve at the crossing time.
Fotometria ubvi e_halfa_do_aglomerado_duplo_de_perseus
This document presents UBVI and Hα photometry of 17319 stars in the vicinity of the young double cluster h & χ Persei. The key findings are:
1) The two clusters share a common distance modulus of 11.75±0.05 and ages of log age(yr) = 7.1±0.1 based on the photometry.
2) 33 Be stars are detected in the region, with 8 being new detections, using the V −Hα color as a measure of Hα emission strength.
3) A peak in the Be star fraction is found towards the end of the main sequence, which is discussed in the context of evolutionary enhancement of the Be phenomenon
Keck Integral-field Spectroscopy of M87 Reveals an Intrinsically Triaxial Gal...
The three-dimensional intrinsic shape of a galaxy and the mass of the central supermassive black hole provide key
insight into the galaxy’s growth history over cosmic time. Standard assumptions of a spherical or axisymmetric
shape can be simplistic and can bias the black hole mass inferred from the motions of stars within a galaxy. Here,
we present spatially resolved stellar kinematics of M87 over a two-dimensional 250″ × 300″ contiguous field
covering a radial range of 50 pc–12 kpc from integral-field spectroscopic observations at the Keck II Telescope.
From about 5 kpc and outward, we detect a prominent 25 km s−1 rotational pattern, in which the kinematic axis
(connecting the maximal receding and approaching velocities) is 40° misaligned with the photometric major axis of
M87. The rotational amplitude and misalignment angle both decrease in the inner 5 kpc. Such misaligned and
twisted velocity fields are a hallmark of triaxiality, indicating that M87 is not an axisymmetrically shaped galaxy.
Triaxial Schwarzschild orbit modeling with more than 4000 observational constraints enabled us to determine
simultaneously the shape and mass parameters. The models incorporate a radially declining profile for the stellar
mass-to-light ratio suggested by stellar population studies. We find that M87 is strongly triaxial, with ratios of
p = 0.845 for the middle-to-long principal axes and q = 0.722 for the short-to-long principal axes, and determine
the black hole mass to be ( - ´) 5.37 0.22 10 +
0.25
0.37 9M , where the second error indicates the systematic uncertainty
associated with the distance to M87.
M31 velocity vector
The document describes measurements of the proper motion of the Andromeda Galaxy (M31) using Hubble Space Telescope imaging data from multiple fields observed at two epochs separated by 5-7 years. Background galaxies in the images are used as stationary reference objects to measure the displacement of thousands of M31 stars between epochs. This allows determining M31's absolute proper motion with an accuracy of 12 microarcseconds per year, providing crucial information about M31 and the Local Group's dynamics and future evolution.
apj_825_1_40
This document examines whether galaxy environments and the color-density relation can be robustly measured using photometric redshift (photo-z) surveys. It finds that:
1) Using optimized parameters for density measurements, a correlation between 2D projected density measurements from photo-z surveys and true 3D density can still be revealed, even with photo-z uncertainties up to 0.06.
2) The color-density relation remains visible in photo-z surveys out to z=0.8, despite photo-z uncertainties of 0.02-0.06.
3) A deep (i=25 magnitude) photo-z survey with photo-z uncertainties of 0.02 can measure small-scale galaxy
Eso1216
The ALMA observations of the Fomalhaut debris disk resolve the ring of parent bodies that produce the dust. The parent body ring has a sharp inner edge at 135 AU and outer edge at 151 AU, giving it a width of 16 AU. The ring has a vertical scale height corresponding to an opening angle of 1 degree. The observations are consistent with the ring being confined by shepherd planets. The dust in the ring has a total mass of 0.017 Earth masses, requiring the parent body population to be at least 1.7 Earth masses.
DYNAMICAL ANALYSIS OF THE DARK MATTER AND CENTRAL BLACK HOLE MASS IN THE DWAR...
We measure the central kinematics for the dwarf spheroidal galaxy Leo I using integrated-light measurements and
previously published data. We find a steady rise in the velocity dispersion from 30000 into the center. The integratedlight kinematics provide a velocity dispersion of 11.76±0.66 km s−1
inside 7500. After applying appropriate corrections
to crowding in the central regions, we achieve consistent velocity dispersion values using velocities from individual stars.
Crowding corrections need to be applied when targeting individual stars in high density stellar environments. From
integrated light, we measure the surface brightness profile and find a shallow cusp towards the center. Axisymmetric,
orbit-based models measure the stellar mass-to-light ratio, black hole mass and parameters for a dark matter halo. At
large radii it is important to consider possible tidal effects from the Milky Way so we include a variety of assumptions
regarding the tidal radius. For every set of assumptions, models require a central black hole consistent with a mass
3.3 ± 2×106 M . The no-black-hole case for any of our assumptions is excluded at over 95% significance, with
6.4 < ∆χ
2 < 14. A black hole of this mass would have significant effect on dwarf galaxy formation and evolution.
The dark halo parameters are heavily affected by the assumptions for the tidal radii, with the circular velocity only
constrained to be above 30 km s−1
. Reasonable assumptions for the tidal radius result in stellar orbits consistent with
an isotropic distribution in the velocities. These more realistic models only show strong constraints for the mass of
the central black hole.
A 3d extinction_map_of_the_northern_galactic_plane_based_on_iphas_photometry
This document presents a 3D extinction map of the Northern Galactic Plane derived using photometry from the IPHAS survey. The map was constructed using a hierarchical Bayesian method that simultaneously estimates the distance-extinction relationship and properties of ~38 million stars along each line of sight. The map has fine angular resolution of ~10 arcminutes and distance resolution of 100 pc out to a depth of 5 kpc. In addition to mean extinction, the method also measures differential extinction arising from the fractal structure of the interstellar medium. Both the extinction map and catalogue of stellar parameters are made publicly available.
Obscuration beyond the nucleus: infrared quasars can be buried in extreme com...
This document discusses how infrared quasars can be obscured by compact starbursts in their host galaxies in addition to the canonical dusty torus. The key points are:
1) Infrared quasars in starburst galaxies with star formation rates above 300 solar masses per year have a higher obscured fraction than at lower star formation rates, suggesting the host galaxy interstellar medium can significantly contribute to obscuring the quasar.
2) At star formation rates above 300 solar masses per year, submillimeter galaxies and infrared quasars have similarly compact submillimeter sizes of 0.5-3 kiloparsecs, indicating the dense interstellar medium in these compact starbursts can heavily obscure the quasar, even reaching
Locating Hidden Exoplanets in ALMA Data Using Machine Learning
Exoplanets in protoplanetary disks cause localized deviations from Keplerian velocity in channel maps of
molecular line emission. Current methods of characterizing these deviations are time consuming,and there is no
unified standard approach. We demonstrate that machine learning can quickly and accurately detect the presence of
planets. We train our model on synthetic images generated from simulations and apply it to real observations to
identify forming planets in real systems. Machine-learning methods, based on computer vision, are not only
capable of correctly identifying the presence of one or more planets, but they can also correctly constrain the
location of those planets.
Eso1438a
This document summarizes research measuring the optical polarization of quasars belonging to large-scale quasar groups at redshift z~1.3. Of the 93 quasars observed, 19 were significantly polarized. The polarization vectors of these quasars were found to be either parallel or perpendicular to the directions of the large-scale structures they belong to, with a statistical probability of this being due to random orientations of only about 1%. Quasars with polarization perpendicular to their host structure tended to have broader emission lines, while those parallel had narrower lines, suggesting quasar spin axes are parallel to their host large-scale structures.
Alignment of quasar_polarizations_with_large_scale_structures
This document summarizes research measuring the optical polarization of quasars belonging to large-scale quasar groups at redshift z~1.3. Of 93 quasars observed, 19 were significantly polarized. The polarization vectors of these quasars were found to be either parallel or perpendicular to the directions of the large-scale structures they belong to, with a statistical probability of this being due to random orientations of only ~1%. Quasars with polarization perpendicular to their structures tended to have broader emission lines, while those parallel had narrower lines, suggesting quasar spin axes are parallel to their host large-scale structures.
Similar to Conference poster : Morphometry of galaxies: Asymmetry (20)
Locating Hidden Exoplanets in ALMA Data Using Machine Learning
Locating Hidden Exoplanets in ALMA Data Using Machine Learning
High resolution alma_observations_of_sdp81_the_innermost_mass_profile_of_the_...
High resolution alma_observations_of_sdp81_the_innermost_mass_profile_of_the_...
SPECTROSCOPIC CONFIRMATION OF THE EXISTENCE OF LARGE, DIFFUSE GALAXIES IN THE...
SPECTROSCOPIC CONFIRMATION OF THE EXISTENCE OF LARGE, DIFFUSE GALAXIES IN THE...
Optical proper motion_measurements_of_the_m87_jet_new_results_from_the_hubble...
Optical proper motion_measurements_of_the_m87_jet_new_results_from_the_hubble...
The build up_of_the_c_d_halo_of_m87_evidence_for_accretion_in_the_last_gyr
The build up_of_the_c_d_halo_of_m87_evidence_for_accretion_in_the_last_gyr
The canarias einstein_ring_a_newly_discovered_optical_einstein_ring
The canarias einstein_ring_a_newly_discovered_optical_einstein_ring
The atacama cosmology_telescope_measuring_radio_galaxy_bias_through_cross_cor...
The atacama cosmology_telescope_measuring_radio_galaxy_bias_through_cross_cor...
Signal Synchronization Strategies and Time Domain SETI with Gaia DR3
Signal Synchronization Strategies and Time Domain SETI with Gaia DR3
Fotometria ubvi e_halfa_do_aglomerado_duplo_de_perseus
Fotometria ubvi e_halfa_do_aglomerado_duplo_de_perseus
Keck Integral-field Spectroscopy of M87 Reveals an Intrinsically Triaxial Gal...
Keck Integral-field Spectroscopy of M87 Reveals an Intrinsically Triaxial Gal...
DYNAMICAL ANALYSIS OF THE DARK MATTER AND CENTRAL BLACK HOLE MASS IN THE DWAR...
DYNAMICAL ANALYSIS OF THE DARK MATTER AND CENTRAL BLACK HOLE MASS IN THE DWAR...
A 3d extinction_map_of_the_northern_galactic_plane_based_on_iphas_photometry
A 3d extinction_map_of_the_northern_galactic_plane_based_on_iphas_photometry
Obscuration beyond the nucleus: infrared quasars can be buried in extreme com...
Obscuration beyond the nucleus: infrared quasars can be buried in extreme com...
Locating Hidden Exoplanets in ALMA Data Using Machine Learning
Locating Hidden Exoplanets in ALMA Data Using Machine Learning
Alignment of quasar_polarizations_with_large_scale_structures
Alignment of quasar_polarizations_with_large_scale_structures
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Este documento discute a morfometria e assimetria de galáxias. Apresenta diferentes tipos de galáxias e classificações morfológicas. Propõe novas medidas de assimetria galáctica e aplica análises morfométricas em catálogos de galáxias como EFIGI.
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Este documento apresenta um estudo sobre a evolução morfológica de galáxias realizado por Juliana Cougo Pereira sob a orientação de Fabrício Ferrari. O objetivo é discutir ferramentas que serão usadas para estudar a evolução de galáxias a partir de dados de grandes surveys astronômicos. É apresentada a classificação de galáxias e parâmetros fotométricos e morfológicos extraídos de imagens como curva de brilho, perfil de brilho, concentração e assimetria.
Relatorio de Neurofísica - Escolas de Inverno do IFGW 2013
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Módulo didático nanotecnologia
1) O documento propõe integrar o ensino de nanotecnologia com física moderna e eletromagnetismo no ensino médio.
2) Foram realizadas três aulas abordando nanotecnologia, eletromagnetismo e modelos atômicos com experimentos, melhorando o conhecimento dos alunos de 30% para 60%.
3) A abordagem interdisciplinar foi bem-sucedida em introduzir conceitos complexos aos alunos.
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Micronuclei test.M.sc.zoology.fisheries.
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
快速办理(UAM毕业证书)马德里自治大学毕业证学位证一模一样
学校原件一模一样【微信：741003700 】《(UAM毕业证书)马德里自治大学毕业证学位证》【微信：741003700 】学位证，留信认证（真实可查，永久存档）原件一模一样纸张工艺/offer、雅思、外壳等材料/诚信可靠,可直接看成品样本，帮您解决无法毕业带来的各种难题！外壳，原版制作，诚信可靠，可直接看成品样本。行业标杆！精益求精，诚心合作，真诚制作！多年品质 ,按需精细制作，24小时接单,全套进口原装设备。十五年致力于帮助留学生解决难题，包您满意。
本公司拥有海外各大学样板无数，能完美还原。
1:1完美还原海外各大学毕业材料上的工艺：水印，阴影底纹，钢印LOGO烫金烫银，LOGO烫金烫银复合重叠。文字图案浮雕、激光镭射、紫外荧光、温感、复印防伪等防伪工艺。材料咨询办理、认证咨询办理请加学历顾问Q/微741003700
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四.办理各国各大学文凭(一对一专业服务,可全程监控跟踪进度)
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◇申请留学生创业基金
留信网认证的作用:
1:该专业认证可证明留学生真实身份
2:同时对留学生所学专业登记给予评定
3:国家专业人才认证中心颁发入库证书
4:这个认证书并且可以归档倒地方
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6:个人职称评审加20分
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EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
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.
11.1 Role of physical biological in deterioration of grains.pdf
Storagedeteriorationisanyformoflossinquantityandqualityofbio-materials.
Themajorcausesofdeteriorationinstorage
•Physical
•Biological
•Mechanical
•Chemical
Storageonlypreservesquality.Itneverimprovesquality.
Itisadvisabletostartstoragewithqualityfoodproduct.Productwithinitialpoorqualityquicklydepreciates
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...Scintica Instrumentation
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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.
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Direct Seeded Rice - Climate Smart Agriculture
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ESR spectroscopy in liquid food and beverages.pptx
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
The cost of acquiring information by natural selection
This is a short talk that I gave at the Banff International Research Station workshop on Modeling and Theory in Population Biology. The idea is to try to understand how the burden of natural selection relates to the amount of information that selection puts into the genome.
It's based on the first part of this research paper:
The cost of information acquisition by natural selection
Ryan Seamus McGee, Olivia Kosterlitz, Artem Kaznatcheev, Benjamin Kerr, Carl T. Bergstrom
bioRxiv 2022.07.02.498577; doi: https://doi.org/10.1101/2022.07.02.498577
Farming systems analysis: what have we learnt?.pptx
Presentation given at the official farewell of Prof Ken Gillet at Wageningen on 13 June 2024
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
A proprietary approach developed by bringing together the best of learning theories from Psychology, design principles from the world of visualization, and pedagogical methods from over a decade of training experience, that enables you to: Learn better, faster!
Compexometric titration/Chelatorphy titration/chelating titration
Classification
Metal ion ion indicators
Masking and demasking reagents
Estimation of Magnisium sulphate
Calcium gluconate
Complexometric Titration/ chelatometry titration/chelating titration, introduction, Types-
1.Direct Titration
2.Back Titration
3.Replacement Titration
4.Indirect Titration
Masking agent, Demasking agents
formation of complex
comparition between masking and demasking agents,
Indicators/Metal ion indicators/ Metallochromic indicators/pM indicators,
Visual Technique,PM indicators (metallochromic), Indicators of pH, Redox Indicators
Instrumental Techniques-Photometry
Potentiometry
Miscellaneous methods.
Complex titration with EDTA.
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
Ozturkcan, S., Berndt, A., & Angelakis, A. (2024). Mending clothing to support sustainable fashion. Presented at the 31st Annual Conference by the Consortium for International Marketing Research (CIMaR), 10-13 Jun 2024, University of Gävle, Sweden.
Immersive Learning That Works: Research Grounding and Paths Forward
We will metaverse into the essence of immersive learning, into its three dimensions and conceptual models. This approach encompasses elements from teaching methodologies to social involvement, through organizational concerns and technologies. Challenging the perception of learning as knowledge transfer, we introduce a 'Uses, Practices & Strategies' model operationalized by the 'Immersive Learning Brain' and ‘Immersion Cube’ frameworks. This approach offers a comprehensive guide through the intricacies of immersive educational experiences and spotlighting research frontiers, along the immersion dimensions of system, narrative, and agency. Our discourse extends to stakeholders beyond the academic sphere, addressing the interests of technologists, instructional designers, and policymakers. We span various contexts, from formal education to organizational transformation to the new horizon of an AI-pervasive society. This keynote aims to unite the iLRN community in a collaborative journey towards a future where immersive learning research and practice coalesce, paving the way for innovative educational research and practice landscapes.
The debris of the ‘last major merger’ is dynamically young
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
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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.
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EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
11.1 Role of physical biological in deterioration of grains.pdf
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(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...
8.Isolation of pure cultures and preservation of cultures.pdf
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waterlessdyeingtechnolgyusing carbon dioxide chemicalspdf
GBSN - Biochemistry (Unit 6) Chemistry of Proteins
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ESR spectroscopy in liquid food and beverages.pptx
ESR spectroscopy in liquid food and beverages.pptx
The cost of acquiring information by natural selection
The cost of acquiring information by natural selection
Farming systems analysis: what have we learnt?.pptx
Farming systems analysis: what have we learnt?.pptx
Sexuality - Issues, Attitude and Behaviour - Applied Social Psychology - Psyc...
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Compexometric titration/Chelatorphy titration/chelating titration
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Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdf
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The debris of the ‘last major merger’ is dynamically young
The debris of the ‘last major merger’ is dynamically young
Conference poster : Morphometry of galaxies: Asymmetry
- 1. Morphometry of Galaxies: Asymmetry Juliana P. Cougo1, Fabricio Ferrari2 1Universidade Federal de Santa Maria-UFSM, Brazil; 2Universidade Federal do Rio Grande-FURG, Brazil. Objectives 1. To present a detailed study of rotational asymmetry in galaxies for both morphological and physical diagnostic purposes. 2. To present an alternative measure for the asymmetry of galaxies, in comparison with the existing measure A1. Introduction I The quantitative use of asymmetry as a morphological parameter was used
- 2. rst by Schade et al.(1995) as a characterization of distant galaxies observed with the Hubble Space Telescope (HST). Further use of symmetry for galaxies in deep HST images has been carried out by Abraham et al. (1996a, 1996b) and van den Bergh et al.(1996). These papers, however, use asymmetry only as a crude, type-characterization of distant galaxies in the framework of the Hubble Sequence. Attempts to characterize asymmetry for nearby galaxies, and its usefulness as a morphological parameter within existing frameworks was
- 3. rst carried out by Conselice (1997). There has been several attempts to objectively measure galaxy morphology and to classify them accordingly. One relatively successful system is the concentration, asymmetry, smoothness, Gini and M20 (CASGM) system, developed in Abraham (1994), Conselice (2000) and Lotz (2004). Methods I There has been several attempts to objectively measure galaxy morphology and to classify them accordingly. One relatively successful system is the concentration, asymmetry, smoothness, Gini and M20 (CASGM) system, developed in Abraham (1994), Conselice (2000) and Lotz (2004). I Asymmetry A1 The asymmetry is usually measured as the normalized dierence between the original and the rotated galaxy images (Conselice 2000) A1 = X i;j jI(i; j) I(i; j)j P i;j jI(i; j)j B (1) where i, j refers to pixels, I and I is the original and rotated by radians galaxy images, respectively. The center of rotation in such that minimize A1. B is the background asymmetry, which must be estimated and removed from the overall measure. The de
- 4. nition (1) suers from various drawbacks. The background asymmetry must be carefully estimated otherwise the noise in it will dominate the A1 measure. I Asymmetry A3 the Spearman correlation coecient s is more adequate, since it calculates the correlation between the ranked variables, which is a linearization. The asymmetry is then A3 = 1 s(I; I) (2) In our training tests, A3 provide more stable measures than A1 and better separates galaxy classes. Application I We use the galaxies catalog from Frei (1996) and EFIGI, SDSS (Baillard et al.2011) to determine the eciency of asymmetry as a morphological parameter. Also, we studied the correlation between asymmetry and other morphological indices for the EFIGI catalog. Measurements were obtained with the MORFOMETRYKA (Ferrari et al 2015, in preparation). Application:Figure Figure 1: Correlation between (A3) and the concentration (C2),point colors indicates morphological numeric type. Results: Table I Table shows the values of the parameters calculated for the CASG from the algorithm that calculates A3 for a small sample of galaxies in the catalog of Frei et. al (1996). Gal Rp C1 C2 A1 A3 S1 G NGC2768 122 3.89 2.15 0.21 0.77 0.23 0.71 NGC2775 102 3.99 2.24 0.27 0.74 0.25 0.73 NGC2903 158 2.92 1.87 0.31 0.74 0.24 0.76 Table 1: Parameters obtained with the MORFOMETRYKA (Ferrari et al 2015). Results: Figure Figure 2: Demonstration of the
- 5. rst version for the asymmetry A1 as a classi
- 6. er of morphological types of galaxies, where ETG and LTG are early-type (elliptical) and late-type (lenticular and spiral) galaxies. Figure 3: This histogram uses a modi
- 7. cation to asymmetry A3, which proved much more eective at distinguishing the classes because the insertion of the Spearman correlation coecient version. Conclusion I As the use of symmetry to obtain morphological and physical information on galaxies at high redshifts is bound to increase, it is desirable to obtain relations between it and other physical parameters in nearby
- 8. eld galaxies. Using the symmetry methods presented in this paper, physical parameters of galaxies which would otherwise be dicult to obtain could be reasonably estimated. References ABRAHAM, R. G., Tanvir, N. R., Santiago, B. X., Ellis, R.S., Glazebrook, K., and van den Bergh, S. 1996b, MNRAS, 279, L47. A. Baillard, E. Bertin, V. de Lapparent, P. Fouque, S. Arnouts, Y. Mellier, R. Pello, J.-F. Leborgne, P. Prugniel, D. Makarov, L. Makarova, H.J. McCracken, A. Bijaoui, and L. Tasca, 2011: The EFIGI catalogue of 4458 nearby galaxies with detailed morphology, AA 532, 74. CONSELICE C. J. 2003, ApJS, 147, 1. Acknowledgments I The CAPES by funding and supporting this work. Contact Information I Email: julianacougo@gmail.com julianacougo@gmail.com