Search for Gamma Rays from LKP Dark Matter in the UED framework with GLAST a E.Nuss b, J.Cohen-Tanugi c and A.Lionetto d on behalf of GLAST DM & Exotic Physics WG Outlook: 1/ GLAST mission - status 2/ KK Dark Matter with the LAT 3/ Conclusions a b LPTA Montpellier II University c SLAC – Stanford University d Physics Department & INFN Roma Tor Vergata Preliminary Results

GBM correlative observations of transient events Orbit 565 km, circular periode ~95 mns Inclination 28.5 o Lifetime 5 years (min) Launch Date Aug 2007 Launch Vehicle Delta 2920H-10 Launch Site Kennedy Space Center LAT sky coverage 20% of the sky (~2.4 sr) deadtime  as low as 25  s Observing modes All sky survey Pointed observations Re-pointing Capabilities Autonomous Rapid slew speed (75° in < 10 minutes) GLAST and the LAT detector I GBM: ~10 keV - 25 MeV LAT: ~20 MeV GeV

modular pair-conversion telescope : 16 towers surrounded by plastic scintillators Large Area Telescope : Overview (PI: P.Michelson) Silicon Microstrip Tracker ~ 80 m 2 of silicon 8.8 x 10 5 readout channels Strip pitch = 228 µm xy layers interleaved with W converters Total Rad length ~1.5 X 0 Calorimeter Hodoscopic array Array of 1536 CsI(Tl) crystals in 8 layers Total Rad length ~8.5 X 0 Anti-Coincidence Detector 89 scintillator tiles Segmented design 3000 kg, 650 W (allocation) 1.8 m x 1.8 m x 1.0 m 20 MeV – 300 GeV Currently there is no other telescope covering this energy range e+e+ e–e– Silicon Microstrip Tracker Measures  direction  identification Calorimeter Measures  energy Shower imaging Anti-Coincidence Detector Rejects background of charged cosmic rays segmentation removes self-veto effects at high energy 

LAT cosmic ray run

Candidate Gamma-ray Event in First LAT Flight Tower

> All elements of the GLAST mission have completed the fabrication phase and are well into integration. > LAT, GBM, and spacecraft assembly complete by mid > Delivery of the instruments for observatory integration spring/summer > Observatory integration and test summer 2006 through summer CY07. Short term activities for the collaboration : > Data Challenge 2 : March->May 2006 > Beam tests at CERN in summer/autumn 2006 GLAST mission status October 2005 : 16 Tower on the LAT November 2005 ACD on the LAT

SM in D = 5 with 1 compactified extra-dimension (over S 1 / ℤ 2 with S 1 radius R) Every SM field (bulk field) possess a KK tower 1-loop level computation shows that the LKP is well approximated by the first KK mode of the hypercharge gauge boson B(1) a a Reference papers: Servant, Tait Nucl.Phys.B650: ,2003, Bergstrom et al. Phys.Rev.Lett.94:131301,2005 Kaluza-Klein Dark Matter in (minimal) UED II

WMAP results  CDM h 2 = 0.12 ± 0.02 ⇩ ~ 0.5 TeV ≤ m B(1) ≤ ~ 1 TeV (depending on the coannihilation channels) One loop  -chanels are avaible in minimal UED models as through but are out of reach for GLAST due to m B(1) ≥ ~0.5 TeV constraint. Limit from Relic Density

B(1) main annihilation channels Unlike the supersymmetric case, charged lepton production is not helicity suppressed and it is the dominant annihilation channel for masses ≤ 0.5 TeV. We assume the branching ratios computed in Servant, Tait (agree with Bergstrom et al) Charged fermion production : Dominant annihilation channel

We assume a NFW profile with a boost factor b, centered at Galactic Center The differential  -ray flux from the GC is NB:J(  ) = 0.13 · 10 5 b for  = sr and  tot v ~3 · cm 3 s -1 for 800 GeV KK DM Continuum Gamma Ray Flux

Total number of photons per B (1) B (1) annihilation where the sum is over all processes that contribute to primary and secondary gamma rays with B f the corresponding branching ratio. In the following analysis we have considered both the primary and secondary  -ray production Gamma Rays from LKP

Hadronization and/or fragmentation of q-qbar final states We include semihadronic decays of  leptons (fairly hard spectrum) Fornengo et al Phys.Rev.D70:103529,2004 ⇩ parametrization of dN  q  /dE for a center of mass energy ~ 1 TeV. We neglect gauge and Higgs bosons final states. Secondary Contribution

Flux from Secondary Contribution Different approximations - Tasitsiomi, Olinto Phys.Rev.D66:083006, DarkSUSY - Fornengo et al Phys.Rev.D70:103529,20 Very good agreement between the two approxiamations (for mSUGRA) our results are for m B(1) = 0.5, 0.8, 1 TeV

Total flux contribution from LKP of m B(1) = 0.8 TeV and with a boost factor b = 200 Gamma Ray Flux Contributions

Comparison between different spectral shapes primary and secondary contribution mSUGRA and E -2 spectra vs LKP Spectral Shapes

> Whole sky 'realistic' simulation (DC2 IRF) > One Year observations, 30 deg radius FOV Galactic Center centered GLAST simulations Dark Matter NFW profile, m B(1) ~ 500 GeV Diffuse background based on GALPROP code (Point source substracted)

We simulated a 1 year map of the sky with a NFW profile for a LKP with m B(1) = 500 GeV For E thrs = 5 GeV and  = 0.84 sr (30 deg radius FOV) the total integrated flux leads to 5  significance ⇒ for NFW profile and 500 GeV LKP leads to a boost factor of ~20 is needed to reach the 5 sensitivity Preliminary GLAST Sensitivity

>Our (preliminary) computation indicates that, in the energy range E  > 5 GeV, GLAST could detect  -rays from GC via LKP annihilations with moderate boost factors >Connection with ground based Cherenkov arrays (continuum and gamma ray lines) is needed to disantangle KK signal from standard astrophysical signal (~ E -2 spectra) >But this result strongly depends on the background model (need of a precise estimate) >Major conference, first GLAST Symposium, being planned for February 2007 at Stanford. International Organizing Committee formed. > GLAST is planned to be launched in 2007 from the Kennedy Space Center… Conclusions II I Delta 2920 vehicle