Elisabete de Gouveia Dal Pino (IAG-USP, Brazil)

Transcription

1 Unveiling the Gamma Ray Universe Elisabete de Gouveia Dal Pino (IAG-USP, Brazil) On behalf of the CTA Collaboration FAPESP Workshop March, 2015 Thanks to W. Hoffmann, B. Rudak, E.Moulin, A. Zech, D. Mazim, J. Hinton, D. Torres

2

3 TeV sky today (144 sources, 49 extragalactic) tevcat.uchicago.edu/ Supernovae Pulsar wind neb. Stellar clusters, Binary systems Unidentified AGN Starburst-Gal.

4 SEEING COSMIC ACCELERATORS Image accelerators with gamma rays e+, e- : IC, SSC -> g-ray photons Spectra and flux reflect those of acc. particles p + nucleus p +X p o gg p ± m ± n

5 Detecting very high energy gamma rays: Cherenkov telescopes

6

7 Cherenkov Image Cherenkov light pool on the ground: area ~10 5 m 2

8 50 GeV to 50 TeV, collecting area 10 5 m 2, 4º FoV, angular res. ~ 0.1 º (TeV) H.E.S.S. dormant now

9 CTA: What one can (hopefully) afford Key design goals: 10-fold increased sensitivity at TeV energies 10-fold increased effective energy coverage Larger field of view for surveys Improved angular resolution Full sky coverage: and array in each hemisphere

10 REQUIREMENTS & DRIVERS Energy Resolution 10% lines, features Sensitivity & Collection Area 10 all topics Field of View 8 surveys, extended objects Rapid Slewing 20 seconds transients Angular Resolution Few arcminute morphology Energies down to 20 GeV Cosmology++ Energies up to 300 TeV Pevatrons

11 Low-energy section: 4 x 23 m tel. (LST) - Parabolic reflector - FOV: 4-5 degrees energy threshold of some 10 GeV Core-energy array: 23 x 12 m tel. (MST) Davies-Cotton reflector - FOV: 7-8 degrees mcrab sensitivity in the 100 GeV 10 TeV domain (one) possible configuration Southern 100 M Array (2006 costs) High-energy section: 70 x 5-6 m tel. (SST) Davies-Cotton reflector (or Schwarzschild-Couder) - FOV: ~10 degrees 10 km 2 area at multi-tev energies

12 Sensitivity (in units of Crab flux) for detection in each 0.2-decade energy band background and systematics limited rate (=area) limited background limited LST SST MST

13 dark matter Signatures of EBL, IGMF, LIV

14 ANGULAR RESOLUTION

15 CTA SCIENCE CASE

16 Theme 1: Cosmic Particle Acceleration How and where are particles accelerated? How do they propagate? What is their impact on the environment? Theme 2: Probing Extreme Environments Processes close to neutron stars and black holes? Processes in relativistic jets, winds and explosions? Exploring cosmic voids Theme 3: Physics Frontiers beyond the SM What is the nature of Dark Matter? How is it distributed? Is the speed of light a constant for high energy photons? Do axion-like particles exist? EBL and IGMF

17 EXAMPLE: GALACTIC PLANE SURVEY H.E.S.S. CTA, for same exposure expect ~1000 detected sources

18 CTA REACH Current Galactic VHE sources (with distance estimates) HESS CTA

19 CTA VERSUS FERMI TRANSIENT SOURCES Hinton & Funk

20 DARK MATTER ANNIHILATION Canonical cross section

21 GALACTIC CENTER REGION Complex, structured VHE source (BH) Gas clouds illuminated by Pevatron? Dark matter halo emission? Launch of Fermi bubbles? 5 sigma contours

22 CTA TELESCOPES

23 LARGE TELESCOPE (LST) 23 m diameter 389 m 2 dish area 28 m focal length 1.5 m mirror facets 4.5 o field of view 0.1 o pixels Camera over 2 m Carbon-fibre structure for 20 s positioning Active mirror control 4 LSTs on South site 4 LSTs on North site Prototype = 1 st telescope

24 LST FULL PROTOTYPE Will be constructed on La Palma, starting in 2015 Elevation drive prototype Dish structure prototype

25 MEDIUM-SIZED 12 M TELESCOPE OPTIMIZED FOR THE 100 GEV TO ~10 TEV RANGE 100 m 2 dish area 16 m focal length 1.2 m mirror facets 8 o field of view ~2000 x 0.18 o pixels 25 MSTs on South site 15 MSTs on North site Berlin MST prototype operational

26 PHOTOMULTIPLIER CAMERAS Recording signal waveform for interesting (triggered) images Options: Capacitor pipeline + analog trigger + (identical) drawers NectarCam (Pixel cluster prototypes operational) LSTCam (Pixel cluster prototypes operational) Flash-ADC + digital trigger + rack-based electronics Flashcam (144 pixel prototype operational)

27 SST - OPTIMIZED FOR THE RANGE ABOVE 10 TEV SINGLE MIRROR SST PROTOTYPE INAUGURATION JUNE 2

28 DUAL-MIRROR TELESCOPES Vassiliev, Fegan, Brousseau Astropart.Phys.28:10-27,2007 Reduced plate scale Reduced psf Uniform psf across f.o.v. Cost-effective small telescopes with compact sensors (SST-2M) Higher-performance telescopes with small pixels (SCT)

29 SST - OPTIMIZED FOR THE RANGE ABOVE 10 TEV DUAL MIRROR ASTRI SST PROTOTYPE INAUGURATION SEPTEMBER 24

30 ASTRI PROTOTYPE INAUGURATION September 24th, 2014 Sierra la Nave Obs., Catania

31 ASTRI-CTA SST-2M PROTOTYPE

32 ASTRI CAMERA

33 The ASTRI Mini-Array: CTA precursor The goal is the deployment and operation of the mini-array with 9 SST-2M telescopes at the CTA south site Italy South Africa Brasil

34 BRAZILIAN FUNDING FOR ASTRI- CTA-MINI-ARRAY Fundacao de Amparo `a Pesquisa do Estado de Sao Paulo 1.5 MEuro for building 3 SST-2M telescopes of the Mini-Array IAG-USP University of Sao Paulo

35 Made in Brazil CTA Mini-Array Universidade de Sao Paulo Instituto de Astronomia, Geofisica e Ciencias Atmosfericas Elisabete de Gouveia Dal Pino Rodrigo Nemmen Grzegorz Koval Claudio Melioli Reinaldo Santos-Lima Chandra Singh Renato Gimenes (Eng.) Carlos Firmino (Eng.) Vitor de Souza Carlos Todeiro Peixoto Gustavo Rojas (UFSCar) Ivone Albuquerque (IFUSP) Sao Carlos Instituto de Fisica de Sao Carlos Sao Paulo MST support Rio de Janeiro LST support Universidade Federal do Rio Edivaldo M. Santos Joao Torres Mello Centro Brasileiro Pesquisas Fisicas Ulisses Barres de Almeida Ronald Cintra Shellard

36 CTA MEMBERS: 28 COUNTRIES >800 SCIENTISTS AND ENGINEERS FROM >100 INSTITUTIONS Argentina, Armenia, Austria, Brazil, Bulgaria, Czech Republic, Croatia, Finland, France, Germany, Greece, India, Italy, Ireland, Japan, Namibia, Netherlands, Norway, Poland, Slovenia, Spain, South Africa, Sweden, Switzerland, UK, USA

37 SITE CANDIDATES two sites to cover full sky at 20 o -30 o N, S Warning: map not quite accurate

38 Site characterisation Detailed site char., surveys Continued monitoring of environmental and atmospheric conditions Design generic site infrastructure Design sitespecific infrastructure Implement site infrastructure Telescope design and prototyping Produce Pre-Production telescopes Deploy and operate Pre-Production telescopes Site Decision(s) Founding Decision Final design mods. Mass-produce and deploy telescopes Critical Design Review Pre-Production Readiness Reviews Production Readiness Reviews

39 CTA SCIENCE In-depth understanding of known objects and their mechanisms Expected discoveries of new object classes? The fun part: Things we haven t thought of

40 PHOTON PROPAGATION: AXION LIMITS P g g Axion conversion?? De Angelis et al. arxiv: , Sanchez-Conde et al., arxiv: M. Meyer et al. arxiv: Increased transparency of Universe Modulation of spectra In nev Axion mass range comparable to or better than dedicated experiments e.g. H.E.S.S. arxiv:

41 PHOTON PROPAGATION: LI VIOLATION AGN g Earth Velocity dispersion across TeV energy range less than ~20 s for ~10 9 yr travel LIV mass scale > GeV (~E), GeV (~E 2 ) HESS, arxiv: arxiv:

42 A DIFFERENT BEAST: OBSERVATORY Observation proposals Key Science Projects CTA Consortium Data from Key Science Projects CTA Observatory Data CTA Observatory users

43 Gamma ray astronomy traces the energy skeleton of the Universe

44 How do cosmic particle accelerators work? Do do particles propagate? Do do particles influence their cosmic environment?

45 ASTRI DUAL MIRROR CONCEPT

46 FROM CURRENT ARRAYS TO CTA light pool radius R m typical telescope spacing Sweet spot for best triggering and reconstruction: most showers miss it! large detection area more images per shower lower trigger threshold

47 SPECTRA OF SUPERNOVA REMNANTS RX J (SN II/Ib?) No Pevatron yet! Cas A (SN IIb) ( from S. Funk)