W/Z bremsstrahlung as the dominant annihilation channel for dark matter

Journal Article · Sat Jan 01 00:00:00 EST 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.83.013001· OSTI ID:21503854

Bell, Nicole F; Jacques, Thomas D ^[1]; Dent, James B ^[2]; Weiler, Thomas J ^[3]

---

1. School of Physics, University of Melbourne, Victoria 3010 (Australia)
2. Department of Physics and School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287-1404 (United States)
3. Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)

Dark matter annihilation to leptons, {chi}{chi}{yields}ll, is necessarily accompanied by electroweak radiative corrections, in which a W or Z boson is radiated from a final-state particle. Given that the W and Z gauge bosons decay dominantly via hadronic channels, it is thus impossible to produce final-state leptons without accompanying protons, antiprotons, and gamma rays. Significantly, while many dark matter models feature a helicity-suppressed annihilation rate to fermions, radiating a massive gauge boson from a final-state fermion removes this helicity suppression, such that the branching ratios Br(l{nu}W), Br(l{sup +}l{sup -}Z), and Br({nu}{nu}Z) dominate over Br(ll). W/Z bremsstrahlung thus allows indirect detection of many weakly interacting massive particle models that would otherwise be helicity suppressed, or v{sup 2} suppressed. Antiprotons and even antideuterons become consequential final-state particles. This is an important result for future dark matter searches. We discuss the implications of W/Z bremsstrahlung for 'leptonic' dark matter models which aim to fit recent cosmic ray positron and antiproton data.

• OSTI ID: 21503854
• Journal Information: Physical Review. D, Particles Fields, Vol. 83, Issue 1; Other Information: DOI: 10.1103/PhysRevD.83.013001; (c) 2011 American Institute of Physics; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANNIHILATION
ANTIDEUTERONS
ANTIPROTONS
BRANCHING RATIO
BREMSSTRAHLUNG
COSMIC RADIATION
DETECTION
GAMMA RADIATION
HELICITY
INTERMEDIATE BOSONS
NONLUMINOUS MATTER
PARTICLE DECAY
PARTICLE MODELS
POSITRONS
RADIATIVE CORRECTIONS
Z NEUTRAL BOSONS
ANTIBARYONS
ANTILEPTONS
ANTIMATTER
ANTINUCLEI
ANTINUCLEONS
ANTIPARTICLES
BARYONS
BOSONS
CHARGED PARTICLES
CORRECTIONS
DECAY
DEUTERONS
DIMENSIONLESS NUMBERS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
FERMIONS
HADRONS
INTERACTIONS
INTERMEDIATE VECTOR BOSONS
IONIZING RADIATIONS
LEPTONS
MATHEMATICAL MODELS
MATTER
NUCLEI
NUCLEONS
PARTICLE INTERACTIONS
PARTICLE PROPERTIES
PROTONS
RADIATIONS