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Title: Astrophysical constraints on singlet scalars at LHC

Abstract

We consider the viability of new heavy gauge singlet scalar particles at colliders such as the LHC . Our original motivation for this study came from the possibility of a new heavy particle of mass ∼ TeV decaying significantly into two photons at colliders, such as LHC, but our analysis applies more broadly. We show that there are significant constraints from astrophysics and cosmology on the simplest UV complete models that incorporate such new particles and its associated collider signal. The simplest and most obvious UV complete model that incorporates such signals is that it arises from a new singlet scalar (or pseudo-scalar) coupled to a new electrically charged and colored heavy fermion. Here we show that these new fermions (and anti-fermions) would be produced in the early universe, then form new color singlet heavy mesons with light quarks, obtain a non-negligible freeze-out abundance, and remain in kinetic equilibrium until decoupling. These heavy mesons possess interesting phenomenology, dependent on their charge, including forming new bound states with electrons and protons. We show that a significant number of these heavy states would survive for the age of the universe and an appreciable number would eventually be contained within the earth andmore » solar system. We show that this leads to detectable consequences, including the production of highly energetic events from annihilations on earth, new spectral lines, and, spectacularly, the destabilization of stars. The lack of detection of these consequences rules out such simple UV completions, putting pressure on the viability of such new particles at LHC . To incorporate such a scalar would require either much more complicated UV completions or even further new physics that provides a decay channel for the associated fermion.« less

Authors:
;  [1]
  1. Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States)
Publication Date:
OSTI Identifier:
22679914
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ABUNDANCE; ANNIHILATION; ASTROPHYSICS; BOUND STATE; CERN LHC; COSMOLOGY; D QUARKS; DECOUPLING; ELECTRONS; MASS; MESONS; PARTICLE DECAY; PHOTONS; PROTONS; SOLAR SYSTEM; STARS; TEV RANGE; U QUARKS; UNIVERSE

Citation Formats

Hertzberg, Mark P., and Masoumi, Ali, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu. Astrophysical constraints on singlet scalars at LHC. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/04/028.
Hertzberg, Mark P., & Masoumi, Ali, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu. Astrophysical constraints on singlet scalars at LHC. United States. doi:10.1088/1475-7516/2017/04/028.
Hertzberg, Mark P., and Masoumi, Ali, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu. Sat . "Astrophysical constraints on singlet scalars at LHC". United States. doi:10.1088/1475-7516/2017/04/028.
@article{osti_22679914,
title = {Astrophysical constraints on singlet scalars at LHC},
author = {Hertzberg, Mark P. and Masoumi, Ali, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu},
abstractNote = {We consider the viability of new heavy gauge singlet scalar particles at colliders such as the LHC . Our original motivation for this study came from the possibility of a new heavy particle of mass ∼ TeV decaying significantly into two photons at colliders, such as LHC, but our analysis applies more broadly. We show that there are significant constraints from astrophysics and cosmology on the simplest UV complete models that incorporate such new particles and its associated collider signal. The simplest and most obvious UV complete model that incorporates such signals is that it arises from a new singlet scalar (or pseudo-scalar) coupled to a new electrically charged and colored heavy fermion. Here we show that these new fermions (and anti-fermions) would be produced in the early universe, then form new color singlet heavy mesons with light quarks, obtain a non-negligible freeze-out abundance, and remain in kinetic equilibrium until decoupling. These heavy mesons possess interesting phenomenology, dependent on their charge, including forming new bound states with electrons and protons. We show that a significant number of these heavy states would survive for the age of the universe and an appreciable number would eventually be contained within the earth and solar system. We show that this leads to detectable consequences, including the production of highly energetic events from annihilations on earth, new spectral lines, and, spectacularly, the destabilization of stars. The lack of detection of these consequences rules out such simple UV completions, putting pressure on the viability of such new particles at LHC . To incorporate such a scalar would require either much more complicated UV completions or even further new physics that provides a decay channel for the associated fermion.},
doi = {10.1088/1475-7516/2017/04/028},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2017,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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