Observable gravitational waves and $ΔN_{\rm eff}$ with global lepton number symmetry and dark matter

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Borah, Debasish, Das, Nayan, Roshan, Rishav
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866910644963377152
author Borah, Debasish
Das, Nayan
Roshan, Rishav
author_facet Borah, Debasish
Das, Nayan
Roshan, Rishav
contents We study the possibility of testing a dark matter (DM) scenario embedded in a global lepton number symmetry $U(1)_L$ via gravitational waves (GW) and cosmic microwave background (CMB) observations. The spontaneous breaking of $U(1)_L$ symmetry generates the seesaw scale as well as DM mass dynamically. The (pseudo) Nambu-Goldstone boson, known as majoron, acquires non-zero mass due to soft symmetry breaking terms of quadratic type in the scalar potential, which eventually breaks $U(1)_L$ to its $Z_2$ subgroup. The spontaneous symmetry breaking, which effectively breaks $Z_2$, leads to the formation of domain walls (DW), posing a threat to successful cosmology, if allowed to dominate. As gravity does not respect any global symmetries, we consider higher dimensional operators suppressed by the scale of quantum gravity (QG) namely, $Λ_{\rm QG}$ which introduces the required bias leading to DW annihilation and emission of stochastic gravitational waves (GW) observable at near future experiments. The same operators also lead to decay of DM bringing interesting indirect detection aspects. While DM is produced non-thermally via scalar portal interactions, light majoron can give rise to additional $ΔN_{\rm eff}$ within reach of future CMB experiments.
format Preprint
id arxiv_https___arxiv_org_abs_2406_04404
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Observable gravitational waves and $ΔN_{\rm eff}$ with global lepton number symmetry and dark matter
Borah, Debasish
Das, Nayan
Roshan, Rishav
High Energy Physics - Phenomenology
Cosmology and Nongalactic Astrophysics
We study the possibility of testing a dark matter (DM) scenario embedded in a global lepton number symmetry $U(1)_L$ via gravitational waves (GW) and cosmic microwave background (CMB) observations. The spontaneous breaking of $U(1)_L$ symmetry generates the seesaw scale as well as DM mass dynamically. The (pseudo) Nambu-Goldstone boson, known as majoron, acquires non-zero mass due to soft symmetry breaking terms of quadratic type in the scalar potential, which eventually breaks $U(1)_L$ to its $Z_2$ subgroup. The spontaneous symmetry breaking, which effectively breaks $Z_2$, leads to the formation of domain walls (DW), posing a threat to successful cosmology, if allowed to dominate. As gravity does not respect any global symmetries, we consider higher dimensional operators suppressed by the scale of quantum gravity (QG) namely, $Λ_{\rm QG}$ which introduces the required bias leading to DW annihilation and emission of stochastic gravitational waves (GW) observable at near future experiments. The same operators also lead to decay of DM bringing interesting indirect detection aspects. While DM is produced non-thermally via scalar portal interactions, light majoron can give rise to additional $ΔN_{\rm eff}$ within reach of future CMB experiments.
title Observable gravitational waves and $ΔN_{\rm eff}$ with global lepton number symmetry and dark matter
topic High Energy Physics - Phenomenology
Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2406.04404