The Dark Matter Programme of the Cherenkov Telescope Array the CTA Consortium represented by Aldo Morselli INFN Roma Tor Vergata 1 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA PROJECT • Next generation ground based Gamma-ray observatory • Open observatory • Two sites with more than 100 telescopes • Southern Site: Near Paranal, Chile • Northern Site: La Palma, Canary Islands, Spain • 32 nations, ~300M € project +100M € manpower 2 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA sites and example telescope layouts different deployment strategies 3 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA Headquarters and Science Data Centre decision: 14 June 2016 4 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA PERFORMANCE Southern Site: Northern Site: 4 Large-size telescopes 4 Large-size telescopes 25 Medium-size telescopes 15 Medium-size telescopes 70 Small-size telescopes LAT Pass 8 (10y, (l,b)=(0,0)) LAT Pass 8 (10y, (l,b)=(120,45)) 11 ) − 10 -1 s H A -2 W C x Flux Sensitivity (erg cm 1 y e H a r A W C 5 VERITAS 50 h y e a r www.cta-observatory.org (2017-07-05) M A G CTA North 50 h I C 5 0 h 12 − 10 H.E.S.S. 50 h CTA South 50 h 2 − 13 10 E Differential flux sensitivity Differential flux sensitivity 2 1 2 − − 10 10 1 10 10 Energy E (TeV) R 5 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Dark Matter EVIDENCE In 1933, the astronomer Zwicky realized that the mass of the luminous matter in the Coma cluster was much smaller than its total mass implied by the motion of cluster member galaxies. Since then, even more evidence: Rotation curves of galaxies Gravitational lensing Bullet cluster Structure formation as deduced from CMB Data by Plank Ω D m ≈ 26.8% imply: 26.8% Ω M ≈ 4.9% 4.9% 6 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Annihilation channels Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Dark Matter Search: Targets and Strategies Little or no astrophysical uncertainties, but low sensitivity because of expected small branching ratio 8 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Dark Matter Search: Targets and Strategies (Another way to see it) 9 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Classical Dwarf spheroidal galaxies: promising targets for DM detection 10 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
2015: New DES Dwarf Spheroidal Galaxies Candidates LAT Collaboration – DES Collaboration agreement – Feb 2015 - first joint paper “Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data” ApJL 2015, 809,L4,arXiv:1503.02632 • analysis of observations of 8 DES Year 1 Survey new Dwarf Spheroidal Galaxies found by DES: Bechtol, et al. Found 8 new dwarf candidates! arXiv:1503.02584 also found by Koposov, et al. arXiv:1503.02079 figure in DES discovery paper 11 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Dwarf Spheroidal Galaxies: Growing number of known targets 12 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Dwarf Spheroidal Galaxies: CTA Sensitivity Sculptor with SystemaEcs There are several of the newly discovered dSph that have a better case for being a promising target, Will choose most promising targets before observations with the latest knowledge. 13 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Dwarf Spheroidal Galaxies: CTA Sensitivity for different Dwarfs. Dashed lines correspond to ±1 σ on the J-factors N.B. recent doubts on Segue 1 J-factor due to interlopers in stellar-kinematic samples. V. Bonnivard et al., arXiv: 1506.08209 14 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA Galactic Halo DM upper-limits W + W - with systemaEc uncertainEes on the residual τ + τ - cosmic-ray background The predictions shown here can be considered optimistic, even when systematics errors are included, as we do not consider the effect of the Galactic diffuse emission as background for DM searches that can affect the results by ~ 50% This will be investigated in detail in a forthcoming publication by the CTA Consortium. Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA Galactic Halo DM upper-limits Effect of the different Halo profiles Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA, Fermi,HESS DM upper-limits 23 Together Fermi and CTA will probe − 10 most of the space of WIMP models CTA Sculptor dwarf with thermal relic annihilaEon cross secEon The expectaEon for CTA for the − 24 GalacEc Halo 10 CTA LMC is for the Einasto profile and is ) -1 opEmisEc as includes s Fermi 3 only staEsEcal errors. v (cm The effect of the GalacEc diffuse HESS Galactic Halo 25 − 10 emission can affect the results by ~ 50% σ As we saw in the previous slides the limits from dwarfs are much less dependent from the CTA Galactic Halo 26 − 10 systemaEc uncertanEes 254 h W + W - Einasto profile H.E.S.S. GC halo bƃ Fermi dSph stacking 500 h W + W - Einasto profile CTA Galactic Halo 500 h W + W - NFW profile CTA Sculptor dwarf 27 − 10 340 h bƃ NFW profile CTA LMC 0.05 0.1 0.2 1 2 3 4 56 10 20 30 DM mass (TeV) Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA, HESS, FERMI, PLANK DM upper-limits Together Fermi and CTA will probe most of the space of WIMP models 23 − 10 with thermal relic annihilaEon cross secEon The expectaEon for CTA is for the WMAP Einasto profile and is opEmisEc as includes only staEsEcal errors. 24 − 10 The effect of the GalacEc diffuse Planck ) emission can affect the results -1 s 3 by ~ 50% v (cm Fermi HESS Galactic Halo 25 − 10 σ CTA Galactic Halo 26 − 10 W + W - Einasto profile HESS Galactic halo (254 h) bƃ Fermi dSph stacking (15 dSphs, 5 yrs) WMAP9 PLANCK 27 − Einasto, W + W - 10 CTA Galactic halo, 500 h 0.06 0.1 0.2 1 2 3 4 56 10 20 30 DM mass (TeV) Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
DM limit improvement estimate in 15 years (2008- 2023) CTA GC Halo 500 h Fermi Fermi 15 Years, 45 dwarfs CTA sensitivity curve from Carr et al. 2015 500 hr, statistical only, NFW, 30 GeV threshold arXiv:1508.06128 Together Fermi and CTA will probe most of the space of WIMP models with thermal relic annihilaEon cross secEon Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
CTA DM DetecEon Strategy First 3 years • The principal target is the GalacEc Center Halo (most intense diffuse emission regions removed) • Best dSph as “cleaner” environment for cross-checks and verificaEon (if hint of strong signal) Next 7 years • If there is detecEon in GC halo data set (525h) • Strong signal: conEnue with GC halo in parallel with best dSph to provide robust detecEon • Weak signal: focus on GC focus to increase data set unEl systemaEc errors can be kept under control • If no detecEon in GC halo data set • Focus observaEon on the best target at that Eme to produce legacy limits. 20 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
21 Aldo Morselli, INFN Roma Tor Vergata Dark Matter and CTA ICRC 2017 19 July 2017
Recommend
More recommend
