Distinctive GWBs from eccentric inspiraling SMBH binaries with a DM spike

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Hu, Li, Cai, Rong-Gen, Wang, Shao-Jiang
Format: Preprint
Publié: 2023
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866913716919861248
author Hu, Li
Cai, Rong-Gen
Wang, Shao-Jiang
author_facet Hu, Li
Cai, Rong-Gen
Wang, Shao-Jiang
contents Recent detections of a low-frequency gravitational wave background (GWB) from various pulsar-timing-array (PTA) observations have renewed the interest in the inspiraling supermassive black hole binaries (SMBHBs), whose population is believed to be the most promising candidate with possible generalizations from including either orbital eccentricity or dark matter (DM) spike. In this paper, we show that the inclusion of both can further display distinctive features detectable in future PTA observations. With a typical initial eccentricity $e_0\sim\mathcal{O}(0.1)$ for the inspiraling SMBHBs, even a shallow DM spike can easily drive the orbital eccentricity close to $1$, leaving behind a large turnover eccentricity when GWs begin to dominate the orbital circularization. In particular, the DM spike index $γ_\mathrm{sp}$ universally manifests itself in the characteristic strain by $h_c\sim f^{7/6-γ_\mathrm{sp}/3}$ in the far infrared and features a novel oscillation structure at low frequencies. Future PTA detection of such characteristics would be the smoking gun for the DM spike and even reveal the nature of DM.
format Preprint
id arxiv_https___arxiv_org_abs_2312_14041
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Distinctive GWBs from eccentric inspiraling SMBH binaries with a DM spike
Hu, Li
Cai, Rong-Gen
Wang, Shao-Jiang
General Relativity and Quantum Cosmology
Cosmology and Nongalactic Astrophysics
High Energy Astrophysical Phenomena
High Energy Physics - Phenomenology
Recent detections of a low-frequency gravitational wave background (GWB) from various pulsar-timing-array (PTA) observations have renewed the interest in the inspiraling supermassive black hole binaries (SMBHBs), whose population is believed to be the most promising candidate with possible generalizations from including either orbital eccentricity or dark matter (DM) spike. In this paper, we show that the inclusion of both can further display distinctive features detectable in future PTA observations. With a typical initial eccentricity $e_0\sim\mathcal{O}(0.1)$ for the inspiraling SMBHBs, even a shallow DM spike can easily drive the orbital eccentricity close to $1$, leaving behind a large turnover eccentricity when GWs begin to dominate the orbital circularization. In particular, the DM spike index $γ_\mathrm{sp}$ universally manifests itself in the characteristic strain by $h_c\sim f^{7/6-γ_\mathrm{sp}/3}$ in the far infrared and features a novel oscillation structure at low frequencies. Future PTA detection of such characteristics would be the smoking gun for the DM spike and even reveal the nature of DM.
title Distinctive GWBs from eccentric inspiraling SMBH binaries with a DM spike
topic General Relativity and Quantum Cosmology
Cosmology and Nongalactic Astrophysics
High Energy Astrophysical Phenomena
High Energy Physics - Phenomenology
url https://arxiv.org/abs/2312.14041