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Title: Freeze-In dark matter with displaced signatures at colliders

Abstract

Dark matter, X, may be generated by new physics at the TeV scale during an early matter-dominated (MD) era that ends at temperature T{sub R}≪ TeV. Compared to the conventional radiation-dominated (RD) results, yields from both Freeze-Out and Freeze-In processes are greatly suppressed by dilution from entropy production, making Freeze-Out less plausible while allowing successful Freeze-In with a much larger coupling strength. Freeze-In is typically dominated by the decay of a particle B of the thermal bath, B→X. For a large fraction of the relevant cosmological parameter space, the decay rate required to produce the observed dark matter abundance leads to displaced signals at LHC and future colliders, for any m{sub X} in the range keV

Authors:
; ; ;  [1]
  1. Berkeley Center for Theoretical Physics, Department of Physics,and Theoretical Physics Group, Lawrence Berkeley National Laboratory,University of California,Berkeley, CA 94720 (United States)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22458412
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 12; Other Information: PUBLISHER-ID: JCAP12(2015)024; OAI: oai:repo.scoap3.org:13014; 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; CERN LHC; COSMOLOGICAL INFLATION; COSMOLOGY; ENTROPY; GEV RANGE; HIGGS BOSONS; KEV RANGE; NONLUMINOUS MATTER; RADIATIONS; SUPERSYMMETRY; TEV RANGE

Citation Formats

Co, Raymond T., D’Eramo, Francesco, Hall, Lawrence J., and Pappadopulo, Duccio. Freeze-In dark matter with displaced signatures at colliders. United States: N. p., 2015. Web. doi:10.1088/1475-7516/2015/12/024.
Co, Raymond T., D’Eramo, Francesco, Hall, Lawrence J., & Pappadopulo, Duccio. Freeze-In dark matter with displaced signatures at colliders. United States. doi:10.1088/1475-7516/2015/12/024.
Co, Raymond T., D’Eramo, Francesco, Hall, Lawrence J., and Pappadopulo, Duccio. 2015. "Freeze-In dark matter with displaced signatures at colliders". United States. doi:10.1088/1475-7516/2015/12/024.
@article{osti_22458412,
title = {Freeze-In dark matter with displaced signatures at colliders},
author = {Co, Raymond T. and D’Eramo, Francesco and Hall, Lawrence J. and Pappadopulo, Duccio},
abstractNote = {Dark matter, X, may be generated by new physics at the TeV scale during an early matter-dominated (MD) era that ends at temperature T{sub R}≪ TeV. Compared to the conventional radiation-dominated (RD) results, yields from both Freeze-Out and Freeze-In processes are greatly suppressed by dilution from entropy production, making Freeze-Out less plausible while allowing successful Freeze-In with a much larger coupling strength. Freeze-In is typically dominated by the decay of a particle B of the thermal bath, B→X. For a large fraction of the relevant cosmological parameter space, the decay rate required to produce the observed dark matter abundance leads to displaced signals at LHC and future colliders, for any m{sub X} in the range keV},
doi = {10.1088/1475-7516/2015/12/024},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 12,
volume = 2015,
place = {United States},
year = 2015,
month =
}
  • Dark matter, X, may be generated by new physics at the TeV scale during an early matter-dominated (MD) era that ends at temperature T{sub R} || TeV. Compared to the conventional radiation-dominated (RD) results, yields from both Freeze-Out and Freeze-In processes are greatly suppressed by dilution from entropy production, making Freeze-Out less plausible while allowing successful Freeze-In with a much larger coupling strength. Freeze-In is typically dominated by the decay of a particle B of the thermal bath, B → X. For a large fraction of the relevant cosmological parameter space, the decay rate required to produce the observed dark matter abundance leadsmore » to displaced signals at LHC and future colliders, for any m{sub X} in the range keV  < m{sub X} < m{sub B} and for values of m{sub B} accessible to these colliders. This result applies whether the early MD era arises after conventional inflation, when T{sub R} is the usual reheat temperature, or is a generic MD era with an alternative origin. In the former case, if m{sub X} is sufficiently large to be measured from kinematics, the reheat temperature T{sub R} can be extracted. Our result is independent of the particular particle physics implementation of B → X, and can occur via any operator of dimension less than 8 (4) for a post-inflation (general MD) cosmology. An interesting example is provided by DFS axion theories with TeV-scale supersymmetry and axino dark matter of mass GeV to TeV, which is typically overproduced in a conventional RD cosmology. If B is the higgsino, h-tilde , Higgs, W and Z particles appear at the displaced decays, h-tilde  →  h-tilde  a, Z ã and h-tilde {sup ±} → W{sup ±} ã. The scale of axion physics, f, is predicted to be in the range (3×10{sup 8}—10{sup 12}) GeV and, over much of this range, can be extracted from the decay length.« less
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