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Galaktische Gamma-Astronomie

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Ein (hoffentlich) allgemein-verständlicher Vortrag zu kosmischen Beschleunigern und Gammastrahlungs-Quellen in unserer Galaxie, der Milchstrasse. Vortrag gehalten im Haus der Astronomie, Heidelberg vom 10. März 2016. Videos sind leider nicht sichtbar im PDF.

An introduction to Galactic gamma-ray astronomy for the general public.

Published in: Science
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Galaktische Gamma-Astronomie

  1. 1. Galaktische
 Gamma-Astronomie 
 Vortragsreihe “Faszination Astronomie”
 Haus der Astronomie, Heidelberg
 10. März 2016 Christoph Deil

  2. 2. Übersicht 1. Was ist Gamma-Strahlung? 2. Wie entsteht kosmische Gamma-Strahlung? 3. Wie misst man kosmische Gamma-Strahlung?
 Teleskope für Gamma-Strahlung. Fokus auf Fermi-LAT und H.E.S.S. 4. Was haben wir entdeckt?
 Galaktische Quellen kosmischer Gamma-Strahlung 5. Wie geht’s weiter?
 Die Zukunft — Cherenkov Telescope Array (CTA)
  3. 3. Was ist
 Gamma-Strahlung?
  4. 4. Gamma-Strahlung ist Licht!
  5. 5. Sichtbares Spektrum ist ca. eine Oktave
 (Faktor 2 in Frequenz) kurze Wellenlänge
 hohe Frequenz hohe Energie lange Wellenlänge
 tiefe Frequenz niedrige Energie Sichtbares Licht Licht aus dem Kosmos: ein 15 meter langes Klavier!
  6. 6. SN 1006
  7. 7. Der Nachthimmel in verschiedenem Licht Planetariums-Projektor
  8. 8. Licht ist eine elektromagnetische Welle. Licht ist auch ein Strom aus Licht-Teilchen = Photonen. Gamma-Strahlung besteht aus den
 höchst-energetischen Photonen. Energie
  9. 9. Photon-Energie in Einheit “Elektron-Volt” = eV Optisch 1 eV Röntgen 1 keV = 1000 eV Gamma 1 MeV — 1 GeV — 1 TeV • 1 GeV = 10^9 eV = 1,000,000,000 eV • 1 TeV = 10^12 eV = 1,000,000,000,000 eV
  10. 10. Wie entsteht kosmische Gamma-Strahlung?
  11. 11. Thermische Strahlung T ~ 6000 K
 E ~ 1 eV
  12. 12. Temperatur ~ Energie
  13. 13. Teilchen Spektrum Fluss Radio Optisch Röntgen z.B. Energie-Verteilung
 der Teilchen in der
 Sonnenoberfläche Sonne
 6000 K
 1 eV EnergieGamma
  14. 14. Teilchen-Spektrum Energie Fluss Radio Optisch Röntgen Gamma SN 1006
 Eine Million Grad
 1 keV Sonne
 6000 K
 1 eV
  15. 15. Teilchen-Spektrum Fluss Radio Optisch Röntgen EnergieGamma ? T ~ 10^3 K
 E ~ 1 eV T ~ 10^6 K
 E ~ 1 keV T ~ 10^12 K
 E ~ 1 GeV
  16. 16. Teilchen-Spektrum Fluss Radio Optisch Röntgen EnergieGamma T ~ 10^3 K
 E ~ 1 eV T ~ 10^6 K
 E ~ 1 keV Es gibt keine Objekte
 im die viel heißer sind als ein paar Millionen Grad! Gamma-Strahlung
 ist nicht-thermisch!
  17. 17. Kosmische
 Teilchen-Beschleuniger!!! Gamma geladene Teilchen
  18. 18. Teilchen-Spektrum Fluss Radio Optisch Röntgen EnergieGamma T ~ 10^3 K
 E ~ 1 eV T ~ 10^6 K
 E ~ 1 keV Thermisch Nicht-thermisch
  19. 19. Wie entstehen aus den geladenen Teilchen Gammas? Atome Licht 2. “Target” 1. energetisches
 geladenes Teilchen Atomkerne
 (z.B. Proton,
 Helium, Eisen) Elektron
 (oder Positron) +
  20. 20. Proton + Proton “Pion-Zerfall”, “hadronische Gamma-Strahlung”
  21. 21. Elektron + Photon “Inverser Compton Effekt”, “leptonische Gamma-Strahlung”
  22. 22. Photon-Spektrum
 von Protonen Fluss Radio Optisch Röntgen EnergieGamma Thermisch Nicht-thermisch Pion-Zerfall
  23. 23. Photon-Spektrum
 von Elektronen Fluss Radio Optisch Röntgen EnergieGamma Thermisch Nicht-thermisch
 Invers-Compton Nicht-thermisch Synchrotron
  24. 24. Photon-Spektrum
 von SN 1006 Fluss Radio Optisch Röntgen EnergieGamma
  25. 25. Kosmische Strahlung
  26. 26. AnzahlTeilchenaufderErdatmosphäreproFlächeundZeit Energie1 (GeV) 1,000,000,000,000 1 10,000,000,000,000,000,000,000,000,000,000,000 Ein Teilchen pro cm2 pro Sekunde Ein Teilchen pro m2 pro Jahr Ein Teilchen pro km2 pro Jahrhundert Weltgrößter Teilchenbeschleuniger (LHC am CERN)
  27. 27. Supernova-Überreste als Galaktische kosmische Teilchen-Beschleuniger Fritz Zwicky 1933
 “Genug Energie” Tycho's SNR
 1572 Enrico Fermi 1949
 “Shock-Beschleunigung”
  28. 28. Fermi Schock-Beschleunigung
  29. 29. Fermi Schock Beschleunigung Wie Tennis-Spielen
 mit einem Laster…
  30. 30. Der Himmel der kosmischen Strahlung ist gleichförmig auf dem 0.1%-Niveau
  31. 31. = Gamma-Strahlung fliegt gerade
 und zeigt uns die kosmischen
 Teilchen-Beschleuniger Geladene kosmische Strahlung
 verliert Richtungs-Info
  32. 32. Wie misst man kosmische Gamma-Strahlung?
 Teleskope für Gamma-Strahlung.
 Fokus auf Fermi-LAT und H.E.S.S.
  33. 33. Gamma-Spiegel?
  34. 34. Paar-Erzeugungs
 Weltraum-Teleskop
  35. 35. Fermi-LAT — Start 2008
  36. 36. Fermi-LAT
 (LAT = Large Area Telescope)
  37. 37. Elektron + Positron
 Paar-Erzeugung
  38. 38. Fermi-LAT Komponenten Tracker Anti-Koinzidenz-Schild Kalorimeter
  39. 39. Fermi-LAT • Fermi-LAT ist super im Energie- Bereich
 100 MeV — 1 TeV • Bei Energien > 1 TeV ist es zu klein um Photonen zu sammeln. • Vom hellste TeV-Gamma-Quelle, der Krebs-Nebel, hat es seit 2008 nur ein paar Photonen detektiert. • Für > TeV Astronomie brauchen wir eine andere Methode! 1 m x 1 m
  40. 40. Tscherenkov-Teleskop Array am Boden
  41. 41. 4 Detektions-
 Prinzip Gamma Elektromagnetischer Schauer
 (viele Elektronen und Positronen) Tscherenkov-Licht Teleskope am Boden 10 nano-Sekunden Bild 1 km^2 1 m^2
  42. 42. Teleskop-Arrays Stereoskopie! Viele Schauer-Bilder
 -> viele Photonen
 -> gute Richtungs-Bestimmung
 -> gute Energie-Bestimmung
  43. 43. HESS-1: 4×12m HESS-2: +28m tel. MAGIC: 2x 17m tels. VERITAS: 4x 10m tels. 44
  44. 44. H.E.S.S. — High Energy Stereoscopic System
  45. 45. 2003 2002 2012 2003 2004 H.E.S.S. — High Energy Stereoscopic System
  46. 46. 14.13 m 33.68 m 14.13 m 14.13 m 14.13 m H.E.S.S. 1 12 m
 100 m^2 H.E.S.S. 2 30m x 20m
 600 m^2
  47. 47. 60 meter hoch Mensch
  48. 48. Wie schwer ist
 H.E.S.S. 2 ? 10 – 50 –100 ?
  49. 49. Wie schwer ist
 H.E.S.S. 2 ? 100 Elefanten x 6 Tonnen = 600 Tonnen
  50. 50. Ein Tag beim Bau
 von H.E.S.S. 2
  51. 51. Eine Nacht — Beobachtungen mit den H.E.S.S. Teleskopen
  52. 52. Was haben wir entdeckt? Galaktische Quellen kosmischer Gamma-Strahlung
  53. 53. Fermi-LAT macht das erste gute Bild vom Gamma-Himmel!
  54. 54. Fermi-LAT Diffuse Galaktische Emission Diffuse extra-galaktische emission Fermi Bubbles 3000 Quellen!
  55. 55. ~2000 Blazare Aktive super-massive Schwarze Löcher in
 anderen Galaxien machen Jets von Teilchen
  56. 56. Blazare sind sehr variabel
  57. 57. ~150 PulsarePulsare sind schnell rotierende Neutronen-Sterne,
 mit extrem hohen magnetischen und elektrischen
 Feldern in ihrer “Magnetosphäre”. Vela-Pulsar
 Die hellste Quelle
 am Fermi-Himmel.
  58. 58. Pulsar
  59. 59. Supernova-Überreste IC 443 W44
  60. 60. Supernova-Überreste als kosmische Proton-Beschleuniger nachgewiesen! 100 Jahre nach Victor Hess
  61. 61. Fermi-Bubbles
  62. 62. Fermi-Bubbles
  63. 63. Illustrations by Ron Miller GIANT BUBBLES OF THE MILKY WAY By Douglas Finkbeiner, Meng Su and Dmitry Malyshev
  64. 64. Fermi Hoch-Energie Survey
 (50 GeV - 2 TeV) Bei hohen Energien geht Fermi-LAT die Statistik aus …
  65. 65. H.E.S.S. Survey
 E > 1 TeV Viel kleineres Gesichts-Feld
 als Fermi-LAT, dafür mehr
 Photonen und bessere
 räumliche Auflösung.
  66. 66. H.E.S.S. Survey
 E > 1 TeV
  67. 67. Stars: Galactic TeV sources outside HGPS region Triangles: Galactic GeV sources (1FHL) Image: Planck CO map 250 o 65 0 o R. Hurt
 NASA H.E.S.S. Survey
  68. 68. H.E.S.S. Survey Das erste TeV-Bild der Milchstrasse! Das Ergebnis von 6000
 Einzel-Beobachtungen von 2004 — 2014
  69. 69. H.E.S.S. Survey 77 Quellen — 
 extrem energiereiche kosmische Teilchenbeschleuniger!
  70. 70. H.E.S.S. Quell-Katalog Pulsarwind-Nebel Supernova-Überreste
  71. 71. Pulsar-wind-nebel Unbekannt Binär-System t = 10,000 yrs 20,000 yrs log ( 1 tivistic gas in three two-dimensional simulations with varying resolutions. We also plot the e†ective value of for these three simulations in Figure 6. Up until aR p /R 1 time of D35,000 yr, all three simulations are quite similar. Once the Rayleigh-Taylor instability kicks in, however, the resolution-dependent e†ects of mixing become quite evident. Independent of the numerical resolution, it is clear that the mixing of relativistic gas and thermal gas is very efficient. 4.2. Evolution in Nonuniform Media We have repeated our two-dimensional simulation with the addition of a density gradient in the ambient medium with the goal of understanding the displacement of the pulsar bubble seen in the Vela SNR. Following Dohm- FIG. 8.ÈEvolution of the pulsar nebula/supernova remnant for the mod electronic edition of the Journal for a color version of this Ðgure.] t=10,000yrs20,000yrs30,000yrs56,000yrs log(ρ/ρc) 0 1 threetwo-dimensionalsimulationswith ions.Wealsoplotthee†ectivevalueof threesimulationsinFigure6.Upuntila 0yr,allthreesimulationsarequitesimilar. igh-Taylorinstabilitykicksin,however,the ndente†ectsofmixingbecomequite ndentofthenumericalresolution,itisclear ofrelativisticgasandthermalgasisvery EvolutioninNonuniformMedia eatedourtwo-dimensionalsimulationwith adensitygradientintheambientmedium ofunderstandingthedisplacementofthe seenintheVelaSNR.FollowingDohm- cx suchthatthedensitycontrast,fromaminimumatlarge positiveztoamaximumatlargenegativez,isgivenby (x[1)~1,andHisthecharacteristiclengthscaleover whichthedensitychanges.Thesimulationsshownhereuse x1.2correspondingtoadensitycontrastof5.These simulationsrequirethecomputationofthefulldomaininz (i.e.,noassumptionofequatorialsymmetry).Asaresult,our standardgridof2000zonesrepresentsonlyhalfthe resolutionusedintheprevioustwo-dimensionalmodel. InFigure8weshowtheevolutionofthePWN/SNR systemforanambientmediumlengthscaleofH1]1019 cm,whichcorrespondstothesizeoftheSNRatanageof D500yr.Earlyintheevolution,wecanestimatetheasym- metryintheSNRbyassumingonlyradialmotion,such ionofthepulsarnebula/supernovaremnantforthemodelwithascaleheightofH1]1019cmintheambientmedium.[Seethe theJournalforacolorversionofthisÐgure.] 10,000 yrs No. 2, 2001 PULSAR W FIG. 5.ÈCrushing of the pulsar nebula in a two-dimen is normalized to take out the expansion of the outer shock that follows the outer shock front, so that the f of the grid is always used. The outer shock front remains very nearly follows the time evolution of the one-dimensio within 0.1%. The key di†erence is the instabil shell of ejecta and the rapid mixing driven bility. Even before the PWN/SNR interactio bility of the SSDW (Chevalier et al. 1992) beg out the shell of shocked ejecta. However, gi time between the beginning of the simulation of the reverse shock, there is not enough time bility to grow to signiÐcant amplitude. F PWN/SNR collision, the deceleration of the e the shocked ambient medium (responsible fo instability) increases in magnitude, thereby d rapid Rayleigh-Taylor instability. The result is shell of mixed ejecta and ambient medium a Ðrst two frames of Figure 5. Much more dramatic, however, is the Ra instability working in the opposite direction w pressure of the compressed pulsar bubble begi ate the ejecta shell back outwards. Fro dimensional simulation shown in Figure 2, we drops below D0.5, the pressure in thR p /R 1PWN exceeds that in the SNR and the PW decelerate the shell of shocked ejecta. This a the dense ejecta gas by the low-density PWN to the Rayleigh-Taylor instability. As a result bility, much of the ejecta gas continues toward the SNR almost unabated. In the absence o spherical reverse shock would reach the c remnant at an age of D35000 yr, and inde Figure 5 that some has reached the center by the same process some relativistic gas is displa center. We see two competing e†ects of this inst PWN crushing phase. First, as relativistic ga from the center, it escapes the full compressio ling ejecta seen in one dimension. Second, turbulence driven by this instability leads to ra the thermal and relativistic gasses. To illustrate we compare the e†ective value of inR p /R 1 10,000yrs30,000yrs50,000yrs log(ρ/ρa) 0 −1 0 0.2 0.4 0.6 0.8 1 100010000100000 Rp/R1 time(yrs) No.2,2001PULSARWINDNEBULAEINEVOLVEDSNRs811 FIG.5.ÈCrushingofthepulsarnebulainatwo-dimensionalsimulationusingtheparametersformodelAlistedinTable1.Thelengthscaleoftheimages isnormalizedtotakeouttheexpansionoftheoutershockfront.[SeetheelectroniceditionoftheJournalforacolorversionofthisÐgure.] thatfollowstheoutershockfront,sothatthefullresolution ofthegridisalwaysused. Theoutershockfrontremainsverynearlysphericaland followsthetimeevolutionoftheone-dimensionalmodelto within0.1%.Thekeydi†erenceistheinstabilityofthethin shellofejectaandtherapidmixingdrivenbythisinsta- bility.EvenbeforethePWN/SNRinteraction,theinsta- bilityoftheSSDW(Chevalieretal.1992)beginstospread outtheshellofshockedejecta.However,giventheshort timebetweenthebeginningofthesimulationandthecrash ofthereverseshock,thereisnotenoughtimeforthisinsta- bilitytogrowtosigniÐcantamplitude.Followingthe PWN/SNRcollision,thedecelerationoftheejectashellby theshockedambientmedium(responsiblefortheSSDW instability)increasesinmagnitude,therebydrivingamore rapidRayleigh-Taylorinstability.Theresultisabroadened shellofmixedejectaandambientmediumasseeninthe ÐrsttwoframesofFigure5. Muchmoredramatic,however,istheRayleigh-Taylor instabilityworkingintheoppositedirectionwhenthehigh pressureofthecompressedpulsarbubblebeginstoacceler- atetheejectashellbackoutwards.Fromtheone- dimensionalsimulationshowninFigure2,weseethatonce dropsbelowD0.5,thepressureinthecompressed R p /R 1PWNexceedsthatintheSNRandthePWNbeginsto deceleratetheshellofshockedejecta.Thisaccelerationof thedenseejectagasbythelow-densityPWNgasissubject totheRayleigh-Taylorinstability.Asaresultofthisinsta- bility,muchoftheejectagascontinuestowardthecenterof theSNRalmostunabated.IntheabsenceofaPWN,a sphericalreverseshockwouldreachthecenterofthe remnantatanageofD35000yr,andindeedweseein Figure5thatsomehasreachedthecenterbythistime.In thesameprocesssomerelativisticgasisdisplacedfromthe center. Weseetwocompetinge†ectsofthisinstabilityinthe PWNcrushingphase.First,asrelativisticgasisdisplaced fromthecenter,itescapesthefullcompressionoftheinfal- lingejectaseeninonedimension.Second,thevigorous turbulencedrivenbythisinstabilityleadstorapidmixingof thethermalandrelativisticgasses.Toillustratethesee†ects, wecomparethee†ectivevalueofintheone-and R p /R 1 two-dimensionalsimulationsinFigure6.Wecomputethe radiusofthepulsarbubbleinthetwo-dimensionalsimula- tionbysummingupthevolumeofgaswithc1.66(i.e., includingthepartiallymixedgas)andcalculateane†ective radiusassumingasphericalvolume.Priortothebounce, theone-andtwo-dimensionalsimulationsarenearlyidenti- cal.However,atthemomentofbounce,thePWNinthe two-dimensionalsimulationhasavolumetwicethatofthe PWNintheone-dimensionalsimulation.Thecompressed PWNquicklyreboundsintheone-dimensionalsimulation, butintwo-dimensionsthevolumeofrelativisticgascon- tinuestoshrinkbecauseofnumericalmixing. ThisrapiddepletionofthevolumeofthePWNinthe two-dimensionalsimulationisanartifactofnumericaldif- fusion;whenonenumericalzonecontainsbothrelativistic gas(c4/3)andejectagas(c5/3),themass-weighted averagecisdominatedbythehighdensityoftheejecta.As aresult,themixingÈandsubsequentlossofPWN volumeÈisstronglydependentonthenumericalresolution ofthesimulation.Higherspatialresolutionleadstoless numericalmixingacrossthecontactinterfacebetweenthe FIG.6.ÈEvolutionofthepulsarnebulathroughthecrashofthereverse SNRshockinone(solidline)andtwo(dashedlines)dimensionswithdi†er- entnumericalresolutions. 10,000 yrs No. 2, 2001 PULSAR W FIG. 5.ÈCrushing of the pulsar nebula in a two-dimen is normalized to take out the expansion of the outer shock that follows the outer shock front, so that the f of the grid is always used. The outer shock front remains very nearly follows the time evolution of the one-dimensio within 0.1%. The key di†erence is the instabil shell of ejecta and the rapid mixing driven bility. Even before the PWN/SNR interactio bility of the SSDW (Chevalier et al. 1992) beg out the shell of shocked ejecta. However, gi time between the beginning of the simulation of the reverse shock, there is not enough time bility to grow to signiÐcant amplitude. F PWN/SNR collision, the deceleration of the e the shocked ambient medium (responsible fo 10,000yrs30,000yrs50,000yrs log(ρ/ρa) 0 −1 No.2,2001PULSARWINDNEBULAEINEVOLVEDSNRs811 FIG.5.ÈCrushingofthepulsarnebulainatwo-dimensionalsimulationusingtheparametersformodelAlistedinTable1.Thelengthscaleoftheimages isnormalizedtotakeouttheexpansionoftheoutershockfront.[SeetheelectroniceditionoftheJournalforacolorversionofthisÐgure.] thatfollowstheoutershockfront,sothatthefullresolution ofthegridisalwaysused. Theoutershockfrontremainsverynearlysphericaland followsthetimeevolutionoftheone-dimensionalmodelto within0.1%.Thekeydi†erenceistheinstabilityofthethin shellofejectaandtherapidmixingdrivenbythisinsta- bility.EvenbeforethePWN/SNRinteraction,theinsta- bilityoftheSSDW(Chevalieretal.1992)beginstospread outtheshellofshockedejecta.However,giventheshort timebetweenthebeginningofthesimulationandthecrash ofthereverseshock,thereisnotenoughtimeforthisinsta- bilitytogrowtosigniÐcantamplitude.Followingthe PWN/SNRcollision,thedecelerationoftheejectashellby theshockedambientmedium(responsiblefortheSSDW two-dimensionalsimulationsinFigure6.Wecomputethe radiusofthepulsarbubbleinthetwo-dimensionalsimula- tionbysummingupthevolumeofgaswithc1.66(i.e., includingthepartiallymixedgas)andcalculateane†ective radiusassumingasphericalvolume.Priortothebounce, theone-andtwo-dimensionalsimulationsarenearlyidenti- cal.However,atthemomentofbounce,thePWNinthe two-dimensionalsimulationhasavolumetwicethatofthe PWNintheone-dimensionalsimulation.Thecompressed PWNquicklyreboundsintheone-dimensionalsimulation, butintwo-dimensionsthevolumeofrelativisticgascon- tinuestoshrinkbecauseofnumericalmixing. ThisrapiddepletionofthevolumeofthePWNinthe two-dimensionalsimulationisanartifactofnumericaldif- Pulsar-
 Wind-Nebel Stefan Klepser . Pulsar Wind Nebulae . ICRC . The Hague 2015 PWN Evolution in a Nutshell Free expansion Reverse shock
 interaction Relic stage SNR PWN ▪ Easy & independent ▪ R ~ t6/5 ▪ All the Crab wisdom, e.g. ▪ Kennel & Coroniti 1984 ▪ Martín++, 2012 ▪ ... ▪ Messy & depending on SNR development ▪ Oscillative reverbations ▪ Analytically R ~ t0.3 ▪ Only over-idealized and/or numerical wisdom ▪ Swaluw++ 2001,2004 ▪ ... Pulsar ▪ More messy & more depending on SNR dev. & surroundings ▪ R ~ undefined ▪ Only case-by-case wisdom 2-6 kyr 20-100 kyr? 7 Die meisten Galaktischen TeV-Quellen sind PWN.
 Elektronen und Positronen erzeugen die Emission.
  72. 72. SNR RX J1713-3949 Peter Eger . H.E.S.S. precision measurements of RX J1713.7-3946 . August 201 The new high-resolution H.E.S.S. map ■ exposure: 170 h ■ angular resolution: 0.05º ■ energy threshold: 250 GeV ■ Analysis: Model w/ HiRes cuts
 (de Naurois & Rolland, 2007) 5 Peter Eger . H.E.S.S. precision measurements of RX J1713.7-3946 . August 2015 Mapping the magnetic field 15 Peter, March 18th , 2014, HESS coll. meeting, Potsdam The X-ray hotspots B-field map X-rays: XMM-Newton
 H.E.S.S.-PSF-convolved TeV: H.E.S.S. War in 2004 das erste aufgelöste Gamma-Bild von einem astronomischen Objekt. Jetzt in 2016 haben wir genug Photonen um
 ein Bild des Magnetfeldes zu machen.
  73. 73. Galaktisches Zentrum TeV-Strahlung mit H.E.S.S. 2 deg, 1000 Lichtjahre
  74. 74. Galaktisches Zentrum VLA Radio Bild TeV-Strahlung mit H.E.S.S. Komplexe Emission.
 Vieles ist noch unklar, z.B.
 “Ist Teil der Halo-Emission von dunkler Materie”
 “Welche Quellen erzeugen die Emission auf der rechten Seite?”
 “Ist die zentrale Quelle ein SNR oder das supermassive schwarze Loch?”
 “Wie hängt das Galaktische Zentrum mit den Fermi Bubbles zusammen?”
  75. 75. Wie geht’s weiter? Die Zukunft - Cherenkov Telescope Array
  76. 76. Fermi-LAT Gamma-Teleskope Heute H.E.S.S. MAGIC VERITAS
  77. 77. Super
 Fermi-LAT ? • Geht nicht gut … • Wäre extrem teuer, ein Fermi-LAT kostet 500 Millionen Euro. • Aber ein Cherenkov- Teleskop nur
 ~ 2 Million Euro … 1 Meter
  78. 78. Cherenkov Telescope Array (CTA)
  79. 79. CTA Konsortium ~ 100 Teleskope ~ 200 Millionen Euro ~ 1000 Astronomen
 ~ 30 Länder
  80. 80. 82 CTA Zeitplan
  81. 81. CTA Standorte 20 Teleskope
 auf La Palma 100 Teleskope
 in Chile
  82. 82. Teleskop- und Array-Optimierung • Die letzten Jahre: lange wissenschaftliche Diskussionen und detaillierte Simulationen um das beste Cherenkov Teleskope Array zu machbaren Kosten zu bauen. • 3 Teleskop-Typen: • LST = Large size telescopes • MST = Mid size telescopes • SST = Small size telescopes
  83. 83. ~ 8 LSTs kleiner als H.E.S.S. 2, ähnlich wie MAGIC-Teleskope CTA LST MAGIC
  84. 84. ~ 40 MSTs ähnlich wie VERITAS oder H.E.S.S. Teleskope PrototypinBerlinAdlershof
 MSTKamerasteilweisevonMPIKHeidelberg
  85. 85. ~ 70 SSTs SST Prototyp Einweihung
 (Dezember 2015 in Meudon. Kamera von MPIK Heidelberg.)
  86. 86. CTA Survey Größeres Gesichtsfeld + Bessere Sensitivität
 =
 Survey-Geschwindigkeit
 300 x schneller als H.E.S.S. Simulation LMCLMC jetzt
  87. 87. Galachic Plane Survey
 1000 Stunden ~ 1 Jahr Beobachtung 5°8°
  88. 88. HESS SNR G0.9+0.1 Sgr B2 Sgr A* NRAO: 20cm, 1.1mm, 5 µm CTA PSF HESS PSF 90 Auflösung
  89. 89. (Fast am) Ende
  90. 90. Zusammenfassung • Gamma-Strahlung ist hoch-energetisches Licht.
 Es ist nicht-thermische Emission. • Man kann Gamma-Strahlung mit Satelliten (z.B. Fermi- LAT) oder von der Erde (z.B. H.E.S.S. oder CTA) messen. • Gamma-Astronomie ist ein sehr junger Zweig der Astronomie, vor 10 Jahren gab es noch kein gutes Bild der Milchstraße in Gamma-Licht. • Die Milchstrasse ist voll von kosmischen Teilchen- Beschleunigern (z.B. Pulsare und Supernova-Überreste), die geladene kosmische Strahlung und Gamma- Strahlung erzeugen.
  91. 91. Danke schön • Carolin Liefke, für die Einladung und Organisation für der Reihe “Faszination Astronomie”. • Kollegen, die Bild-Material und Feedback zu dem Vortrag gegeben haben:
 
 Werner Hofmann, Axel Donath, Johannes King, Christopher van Eldik, Mathieu de Naurois, Rolf Bühler, Heinz Völk, Stefan Funk, Karl Kosack, Bernhold Feuerstein
  92. 92. Vielen Dank für
 Ihre Aufmerksamkeit. Fragen?
  93. 93. Backup Folien
  94. 94. HAWC
  95. 95. 30-Nov-2015 F. Salesa Greus - HAWC 14 HAWC SkyMap 150 days (Pass 3)
  96. 96. 30-Nov-2015 F. Salesa Greus - HAWC 15 HAWC SkyMap 150 days (Pass 3) Geminga* - 6σ Mrk 501 - 13σ Galactic Plane Mrk 421 - 17σ Crab Nebula - 38σ

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