Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies. Present status and future prospects

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1 Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies. Present status and future prospects Aldo Morselli INFN Roma Tor Vergata CTA in the quest for Dark Matter and exotic phenomena Milano, Brera, Cupola a Fiore, June Aldo Morselli, INFN Roma Tor Vergata 1

2 Neutralino WIMPs Assume χ present in the Galactic halo χ is its own antiparticle => can annihilate in galactic halo producing gamma-rays, antiprotons, positrons. Antimatter not produced in large quantities through standard processes (secondary production through p + p --> anti p + X) So, any extra contribution from exotic sources (χ χ annihilation) is an interesting signature ie: χ χ --> anti p + X Produced from (e. g.) χ χ --> q / g / gauge boson / Higgs boson and subsequent decay and/ or hadronisation. Aldo Morselli, INFN Roma Tor Vergata 2

3 Annihilation channels Aldo Morselli, INFN Roma Tor Vergata 3

4 Differential yield for each annihilation channel Quite distinctive spectrum (no power-law) solid lines are the total yields, while the dashed lines are components not due to π 0 decays WIMP mass=200gev A.Cesarini, F.Fucito, A.Lionetto, A.Morselli, P.Ullio, Astroparticle Physics, 21, 267, 2004 [astro-ph/ ] Aldo Morselli, INFN Roma Tor Vergata 4

5 Differential yield for b bar for different neutralino mass neutralino mass A.Cesarini, F.Fucito, A.Lionetto, A.Morselli, P.Ullio, Astroparticle Physics, 21, , 2004 [astro-ph/ ] Aldo Morselli, INFN Roma Tor Vergata 5

6 Dwarf spheroidal galaxies (dsph) : promising targets for DM detection Aldo Morselli, INFN Roma Tor Vergata 6

7 Dwarf Spheroidal Galaxies upper-limits No detection by Fermi with 11 months of data. 95% flux upper limits are placed for several possible annihilation final states. Flux upper limits are combined with the DM density inferred by the stellar data (*) for a subset of 8 dsph (based on quality of stellar data) to extract constraints on < v> vs WIMP mass for specific DM models (*) stellar data from the Keck observatory (by Martinez, Bullock, Kaplinghat) Fermi Coll. ApJ 712 (20) [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 7

8 Dwarf Spheroidal Galaxies combined analysis robust constraints including J-factor uncertainties from the stellar data statistical analysis NFW. For cored dark matter profile, the J-factors for most of the dsphs would either increase or not change much Fermi Lat Coll., PRL 7, (2011) [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 8

9 Dwarf Spheroidal Galaxies upper-limits 15 Dwarfs 4-year data 500 MeV to 500GeV M.Ackermann et al., [Fermi Coll.] Phys.Rev.D 89, (2014)[arXiv: ] Aldo Morselli, INFN Roma Tor Vergata 9

10 Dwarf Spheroidal Galaxies upper-limits (6 years ) 15 Dwarfs 6-year data 500 MeV to 500GeV M.Ackermann et al., [Fermi Coll.] PRL accepted [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata

11 Dwarf Spheroidal Galaxies upper-limits (6 years ) M.Ackermann et al., [Fermi Coll.] PRL accepted [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 11

12 Upper limits from AMS antiprotons and Fermi LAT for different halo profiles Jin et al., arxiv: Fermi data from M.Ackermann et al., [Fermi Coll.] PRL accepted [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 12

13 Upper limits from Fermi LAT, Antares, IceCube, Magic IceCube 79 Galactic Center Pamela positron excess positron excess Fermi Lat Dwarfs limit Antares Coll. arxiv: Aldo Morselli, INFN Roma Tor Vergata 13

14 Upper limits from Fermi LAT, IceCube, Veritas IceCube 79 Galactic Center Pamela positron excess positron excess Fermi Lat Dwarfs limit IceCube Coll. arxiv: Aldo Morselli, INFN Roma Tor Vergata 14

15 Dwarf Spheroidal Galaxies upper-limits (6 years ) Astrogam range M.Ackermann et al., [Fermi Coll.] PRL Submitted [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 15

16 2015: An interesting start DES Year 1 Survey Found 8 new dwarf candidates! figure in DES discovery paper LAT Collaboration DES Collaboration agreement Feb first joint paper Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data arxiv: analysis of observations of 8 new Dwarf Spheroidal Galaxies found by DES: Bechtol, et al. arxiv: also found by Koposov, et al. arxiv: Aldo Morselli, INFN Roma Tor Vergata 16

17 New DES Dwarf Spheroidal Galaxy Candidates (Reticulum II) A.Drlica-Wagner et al. [Fermi and DES Coll.] ApJ Letters Submitted [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 17

18 New DES Dwarf Spheroidal Galaxy Candidates Scroll down for video! Based on arxiv: and arxiv: Aldo Morselli, INFN Roma Tor Vergata 18

19 New DES Dwarf Spheroidal Galaxy Candidates A.Drlica-Wagner et al. [Fermi and DES Coll.] ApJ Letters Submitted [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 19

20 New DES Dwarf Spheroidal Galaxy Candidates ( Reticulum II ) A.Drlica-Wagner et al. [Fermi and DES Coll.] ApJ Letters Submitted [arxiv: ] Aldo Morselli, INFN Roma Tor Vergata 20

21 DM limit improvement estimate in years with the composite likelihood approach ( ) years of data instead of 2(5x) 30 dsphs (3x) (supposing that the new optical surveys will find new dsph) -% from spatial extension (source extension increases the signal region at high energy E > GeV, M > 200 GeV ) There are many assumptions in this prediction Doesn t deal with a possible detections. Aldo Morselli, INFN Roma Tor Vergata 21

22 New gamma projects in space AstroGam 300 KeV- GeV (Proposal to ESA for M4 ) Gamma-light (Proposed to ESA but not approved ) Gamma-400 launch foreseen by MeV 3 TeV, an approved Russian γ-ray satellite. Energy resolution (0 GeV) 1 %. Effective area 0.4 m 2. Angular resolution (0 GeV) Science with Gamma-400 Workshop DAMPE: Satellite of similar performance as Gamma-400. An approved Chinese γ-ray satellite. Planned launch HERD: Instrument on the planned Chinese Space Station. Energy resolution (0 GeV) 1 %. Effective area 1-2 m2. Angular resolution (0 GeV) Planned launch around PANGU: suggested as a candidate for the joint small mission between the European Space Agency (ESA) and the Chinese Academy of Science (CAS) Aldo Morselli, INFN Roma Tor Vergata 22

23 Sensitivity of present and future experiments Aldo Morselli, INFN Roma Tor Vergata 23

24 CTA$MC$Prod2$ Add$more$telescope$design.$ More$trigger$types.$ Aiming$at$realis8c$site$parameters:$! al8tude$! geomagne8c$field$! atmospheric$density$profile$! Cherenkov$light$ex8nc8on$! Night$sky$background,$using$single$value$but$it$ " varies$across$the$sky$(stars,$galac8c$plane,$zodiacal$light),$varies$with$8me$ (solar$cycle,$intragnight),$ " varies$with$zenith$angle$(airgglow$layer).$ " For$2662$m:$low$value$~Chile,$high$value$~Leoncito$

25 Telescope$layout$for$Prod2$

26 Detector$response$from$Prod2$ We$use$the$ctools$IRF:$ hqp://cta.irap.omp.eu/ctools/index.html$

27 CTA Dwarf Spheroidal Galaxies upper-limits : Segue 1 work in progress with Gonzalo Rodriguez NFW profile T=0h

28 CTA Prod 2 Dwarf Spheroidal Galaxies upper-limits : B Bbar channel NFW profile T=0h s -1 ] 3 v> [cm <σ ann 24 Ursa minor Draco Scultor Carina Segue 1 Willman 1 25 bb Coma Berenices Thermal Relic cross section m χ [TeV/c 2 ]

29 CTA Prod 2 Dwarf Spheroidal Galaxies upper-limits : τ + τ - channel NFW profile T=0h s -1 ] 3 v> [cm <σ ann 24 Ursa minor Draco Scultor Carina Segue 1 Willman 1 25 τ - τ + Coma Berenices Thermal Relic cross section m χ [TeV/c 2 ]

30 CTA Prod 2 Dwarf Spheroidal Galaxies upper-limits : µ + µ - channel NFW profile T=0h s -1 ] 3 v> [cm <σ ann 24 Ursa minor Draco Scultor Carina Segue 1 Willman 1 25 µ - µ + Coma Berenices Thermal Relic cross section m χ [TeV/c 2 ]

31 CTA Prod 2 New DES Dwarf Spheroidal Galaxy Candidates NFW profile T=0h B Bbar channel s -1 ] 3 v> [cm <σ ann 24 DES J DES J DES J DES J DES J DES J bb DES J DES J Thermal Relic cross section m χ [TeV/c 2 ]

32 CTA Prod 2 New DES Dwarf Spheroidal Galaxy Candidates NFW profile T=0h τ + τ - channel s -1 ] 3 v> [cm <σ ann 24 DES J DES J DES J DES J DES J DES J τ - τ + DES J DES J Thermal Relic cross section m χ [TeV/c 2 ]

33 CTA Prod 2 New DES Dwarf Spheroidal Galaxy Candidates NFW profile T=0h µ + µ - channel s -1 ] 3 v> [cm <σ ann 24 DES J DES J DES J DES J DES J DES J µ - µ + DES J DES J Thermal Relic cross section m χ [TeV/c 2 ]

34 Conclusions Dwarf Spheroidal Galaxies are key targets Aldo Morselli, INFN Roma Tor Vergata 34

35 $Thank$you$!