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Title: Dark forces in the sky: signals from Z{sup ′} and the dark Higgs

Abstract

We consider the indirect detection signals for a self-consistent hidden U(1) model containing a Majorana dark matter candidate, χ, a dark gauge boson, Z{sup ′}, and a dark Higgs, s. Compared with a model containing only a dark matter candidate and Z{sup ′} mediator, the addition of the scalar provides a mass generation mechanism for the dark sector particles and is required in order to avoid unitarity violation at high energies. We find that the inclusion of the two mediators opens up a new two-body s-wave annihilation channel, χχ→sZ{sup ′}. This new process, which is missed in the usual single-mediator simplified model approach, can be the dominant annihilation channel. This provides rich phenomenology for indirect detection searches, allows indirect searches to explore regions of parameter space not accessible with other commonly considered s-wave annihilation processes, and enables both the Z{sup ′} and scalar couplings to be probed. We examine the phenomenology of the sector with a focus on this new process, and determine the limits on the model parameter space from Fermi data on dwarf spheriodal galaxies and other relevant experiments.

Authors:
; ;  [1]
  1. ARC Centre of Excellence for Particle Physics at the Terascale, School of Physics,The University of Melbourne,Victoria 3010 (Australia)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22572126
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 08; Other Information: PUBLISHER-ID: JCAP08(2016)001; OAI: oai:repo.scoap3.org:16638; cc-by Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANNIHILATION; ASTROPHYSICS; COSMOLOGY; COUPLING; HIGGS BOSONS; HIGGS MODEL; INTERMEDIATE VECTOR BOSONS; MAJORANA FERMIONS; NONLUMINOUS MATTER; S WAVES; SPACE VEHICLES; TWO-BODY PROBLEM; U-1 GROUPS

Citation Formats

Bell, Nicole F., Cai, Yi, and Leane, Rebecca K. Dark forces in the sky: signals from Z{sup ′} and the dark Higgs. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/08/001.
Bell, Nicole F., Cai, Yi, & Leane, Rebecca K. Dark forces in the sky: signals from Z{sup ′} and the dark Higgs. United States. doi:10.1088/1475-7516/2016/08/001.
Bell, Nicole F., Cai, Yi, and Leane, Rebecca K. 2016. "Dark forces in the sky: signals from Z{sup ′} and the dark Higgs". United States. doi:10.1088/1475-7516/2016/08/001.
@article{osti_22572126,
title = {Dark forces in the sky: signals from Z{sup ′} and the dark Higgs},
author = {Bell, Nicole F. and Cai, Yi and Leane, Rebecca K.},
abstractNote = {We consider the indirect detection signals for a self-consistent hidden U(1) model containing a Majorana dark matter candidate, χ, a dark gauge boson, Z{sup ′}, and a dark Higgs, s. Compared with a model containing only a dark matter candidate and Z{sup ′} mediator, the addition of the scalar provides a mass generation mechanism for the dark sector particles and is required in order to avoid unitarity violation at high energies. We find that the inclusion of the two mediators opens up a new two-body s-wave annihilation channel, χχ→sZ{sup ′}. This new process, which is missed in the usual single-mediator simplified model approach, can be the dominant annihilation channel. This provides rich phenomenology for indirect detection searches, allows indirect searches to explore regions of parameter space not accessible with other commonly considered s-wave annihilation processes, and enables both the Z{sup ′} and scalar couplings to be probed. We examine the phenomenology of the sector with a focus on this new process, and determine the limits on the model parameter space from Fermi data on dwarf spheriodal galaxies and other relevant experiments.},
doi = {10.1088/1475-7516/2016/08/001},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2016,
place = {United States},
year = 2016,
month = 8
}
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