Kaluza-Klein Dark Matter

TL;DR

It is proposed that cold dark matter is made of Kaluza-Klein particles and avenues for its detection are explored, and the lightest KaluZA-K Klein state is an excellent dark matter candidate if standard model particles propagate in extra dimensions and Kaluzaklein parity is conserved.

Abstract

We propose that cold dark matter is made of Kaluza-Klein particles and explore avenues for its detection. The lightest Kaluza-Klein state is an excellent dark matter candidate if standard model particles propagate in extra dimensions and Kaluza-Klein parity is conserved. We consider Kaluza-Klein gauge bosons. In sharp contrast to the case of supersymmetric dark matter, these annihilate to hard positrons, neutrinos and photons with unsuppressed rates. Direct detection signals are also promising. These conclusions are generic to bosonic dark matter candidates.

Figures (3)

• Figure 1: Predicted spin-dependent proton cross sections (dark-shaded, blue), along with the projected sensitivity of a 100 kg NAIAD array Spooner:kt; and predicted spin-independent proton cross sections (light-shaded, red), along with the current EDELWEISS sensitivity Benoit:2002hf, and projected sensitivities of CDMS Schnee:gf, GENIUS Klapdor-Kleingrothaus:2000eq, and CRESST Bravin:1999fc. (The CRESST projection is long-term and conditional upon increased exposure and improved background rejection.) The predictions are for $m_h = 120~\text{GeV}$ and $0.01 \le r = (m_{q^1} - m_{B^1}) / m_{B^1} \le 0.5$, with contours for specific intermediate $r$ labeled.
• Figure 2: Predicted positron signals (dark shaded) above background (light shaded) as a function of positron energy for $m_{B^1} = m_{e^1_L} = m_{e^1_R} = 100$, 500, 750, and 1000 GeV.
• Figure 3: Integrated photon flux as a function of $m_{B^1}$ for energy thresholds of 1 and 50 GeV. Projected sensitivities for GLAST and MAGIC are also shown.