KIMS & Inelastic DarK Matter(iDM) S.C.Kim (SNU) Korea china workshop 2011

Dark matter search Which is right? Claiming the observation of DM annual modulation Null observation of DM Which is right?

How to reconcile all the experiments? Many ideas have been suggested such as mirror DM, dipolar DM, hidden charged DM, composite DM, electron interacting DM, resonant DM, inelastic DM or Frankenstein DM that patches up the features of several DM models (from Resonannces Blog)

Inelastic dark matter(iDM) Proposed to reconcile the DAMA observation of WIMP and other null observation experiments an excited state * of the dark matter particle with a mass m* - m =  ~ 100keV . => Typical kinetic energy of DM  N -> * N (inelastic scattering) rather than  N ->  N (elastic scattering)

Minimum velocity for recoil Energy, ER mN : mass of target Nucleus µ:reduced mass of WIMP & target Nucleus :mass splitting between  and* min ER

Three key features *Spectrum of events is dramatically changed, suppressing or eliminating low-energy events. ->Spectrum of Conventional WIMP rises exponentially at low energy. But iDM peaks at ER ~20keV or above. ER rate Conventional WIMP spectrum iDM spectrum 20keV

Three key features *Heavier targets favored over lighter targets. For a given ER and , Heavier target mass -> lower min -> greater available range of velocity Iodine(DAMA) is better than Germanium(CDMS).

Three key features f(v) *modulation of the signal enhanced significantly. Mainly high velocity WIMPs are detectible. In these high velocity region, WIMP numbers is changing rapidly. Modulation ratio of DAMA/LIBRA according to  f(v) visible to DAMA visible to DAMA and CDMS Neal Weiner, NYU; IDM 2008

Expected energy spectrum Vesc MN : mass of target Nucleus µ:reduced mass of WIMP/target Nucleus M : mass of WIMP  : 0.3GeV/cm3 Astronomical parameters f(v) ~ usually Maxwell-Boltzmann distribution assumed Vesc = 500 – 600 km/s => 650 km/s (most widely used value) => 544 km/s (MNRAS 379(2007) p755) Velocity dispersion(V0) = 220km/s Vearth = Vsun + Vmodulation

Velocity profiles for WIMP What is the true distribution around Vesc ? There’s long debate about it. J. Wacker Aspen Winter 2011

iDM candidate? Fourth generation neutrino, Higgsino, Sneutrino may be the iDM. Inelasticity seems natural. But,  ~ M v2(kinetic energy of WIMP) must be explained. Too sensitive to the astronomical parameters!

Constraints on iDM from the experiments arXiv:1104.3121 (XENON 100) iDM ruled out?

New version of iDM model Version 1 (PRL 106, 011301(2011)) Scattering off Thallium, not Iodine ? (Tl, A(205)) (I, A(127)) Tl exists at 0.001 level in DAMA NaI(Tl) detector.

New version of iDM model Version 2 (PRD 82, 125011(2010)) Magnetic inelastic dark matter ? inelasticity <= large mass of Iodine magnetic interaction <= large magnetic moment of Iodine

KIMS & iDM the detector of KIMS CsI(Tl) Cs (large magnetic moment & large mass) + I ( the target element of DAMA, large magnetic moment & large mass) + Tl large mass) Whole iDM model can be tested with one experiment!

The Energy spectrum for the Nuclear recoil events from KIMS => Determined from PSD analysis 90 % C.L limit There’s no meaningful excess of NR signals !!!

The Energy spectrum for the Nuclear recoil events from KIMS The annual modulation amplitude from DAMA At 2-4keV, 0.0183±0.0022 counts/day/kg/keV At the corresponding energy range (3.6-5.8 keV) in KIMS, (QF for DAMA =0.08 adopted) The 90 % C.L limit is 0.0098 counts/day/kg/keV This is well below the DAMA modulation amplitude. Any scenario with Iodine for DAMA is not consistent with KIMS results !!!

For thallium recoil scenario, The corresponding energy range for Tl is almost same with I. So, thallium scenario is not likely either.

DAMA & KIMS in iDM model For WIMP velcocity profile, SHM truncation adopted

Summary iDM model has been proposed to reconcile the DAMA & other null results. As some experiments exclude the room for iDM model, new versions of iDM model was suggested. We show that the original and new versions of iDM scenario for DAMA are not consistent with new results of KIMS.