Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Collider Constraints on Dipole-Interacting Dark Matter

Jean-François Fortin, Tim M. P. Tait

TL;DR

This paper investigates dark matter that interacts with the Standard Model primarily through electromagnetic dipole moments, parameterized by a Dirac fermion $\psi$ with magnetic and electric couplings $g_M$ and $g_E$ to the photon. It analyzes both the thermal relic abundance and collider constraints, deriving annihilation cross sections and relic-density relations within an effective-field-theory framework and comparing them to LEP II, Tevatron, and prospective LHC bounds. The results show that a thermal relic is most easily accommodated for DM masses of order a few GeV, with the magnetic case offering partial alignment with DAMA/CoGeNT signals though constrained by low-threshold CDMS results; for masses in the tens to hundreds of GeV, direct-detection limits are typically stronger than collider bounds. Overall, collider constraints (especially LEP II) complement direct-detection searches but are generally weaker across most of the mass range, while the photon portal remains a compelling but challenging avenue for probing light, weakly coupled DM and potential new dark-sector dynamics.

Abstract

Dark matter which interacts through a magnetic or electric dipole moment is an interesting possibility which may help to resolve the discrepancy between the DAMA annual modulation signal and the null results of other searches. In this article we examine relic density and collider constraints on such dark matter, and find that for couplings needed to explain DAMA, the thermal relic density is generically in the right ballpark to account for cosmological measurements. Collider constraints are relevant for light WIMPs, but less constraining that direct searches for masses above about 10 GeV.

Collider Constraints on Dipole-Interacting Dark Matter

TL;DR

This paper investigates dark matter that interacts with the Standard Model primarily through electromagnetic dipole moments, parameterized by a Dirac fermion with magnetic and electric couplings and to the photon. It analyzes both the thermal relic abundance and collider constraints, deriving annihilation cross sections and relic-density relations within an effective-field-theory framework and comparing them to LEP II, Tevatron, and prospective LHC bounds. The results show that a thermal relic is most easily accommodated for DM masses of order a few GeV, with the magnetic case offering partial alignment with DAMA/CoGeNT signals though constrained by low-threshold CDMS results; for masses in the tens to hundreds of GeV, direct-detection limits are typically stronger than collider bounds. Overall, collider constraints (especially LEP II) complement direct-detection searches but are generally weaker across most of the mass range, while the photon portal remains a compelling but challenging avenue for probing light, weakly coupled DM and potential new dark-sector dynamics.

Abstract

Dark matter which interacts through a magnetic or electric dipole moment is an interesting possibility which may help to resolve the discrepancy between the DAMA annual modulation signal and the null results of other searches. In this article we examine relic density and collider constraints on such dark matter, and find that for couplings needed to explain DAMA, the thermal relic density is generically in the right ballpark to account for cosmological measurements. Collider constraints are relevant for light WIMPs, but less constraining that direct searches for masses above about 10 GeV.

Paper Structure

This paper contains 7 sections, 9 equations, 2 figures.

Table of Contents

  1. Introduction
  2. Dark Matter with Dipole Moments
  3. Relic Abundance
  4. Collider Constraints
  5. LEP II Constraints
  6. Hadron Collider Constraints
  7. Discussion and Conclusion

Figures (2)

  • Figure 1: $90\%$ confidence level (CDMS-II, XENON100, DAMA, CoGeNT, LEP, Tevatron) and $5\sigma$ reach (LHC) plots for direct detection and collider experiments for DMDM with magnetic dipole moment. The dash line corresponds to the $90\%$ confidence level plot for the low threshold CDMS analysis.
  • Figure 2: $90\%$ confidence level (CDMS-II, XENON100, DAMA, CoGeNT, LEP, Tevatron) and $5\sigma$ reach (LHC) plots for direct detection and collider experiments for DMDM with electric dipole moment. The dash line corresponds to the $90\%$ confidence level plot for the low threshold CDMS analysis.