Details
| Original language | English |
|---|---|
| Article number | 123507 |
| Number of pages | 15 |
| Journal | Physical Review D |
| Volume | 110 |
| Issue number | 12 |
| Publication status | Published - 3 Dec 2024 |
Abstract
Pulsar timing arrays (PTAs) hunt for gravitational waves (GWs) by searching for the correlations that GWs induce in the time-of-arrival residuals from different pulsars. If the GW sources are of astrophysical origin, then they are located at discrete points on the sky. However, PTA data are often modeled, and subsequently analyzed, via a "standard Gaussian ensemble."That ensemble is obtained in the limit of an infinite density of vanishingly weak, Poisson-distributed sources. In this paper, we move away from that ensemble, to study the effects of two types of "source anisotropy."The first (a), which is often called "shot noise,"arises because there are N discrete GW sources at specific sky locations. The second (b) arises because the GW source positions are not a Poisson process, for example, because galaxy locations are clustered. Here, we quantify the impact of (a) and (b) on the mean and variance of the pulsar-averaged Hellings and Downs correlation. For conventional PTA sources, we show that the effects of shot noise (a) are much larger than the effects of clustering (b).
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Nuclear and High Energy Physics
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In: Physical Review D, Vol. 110, No. 12, 123507, 03.12.2024.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Source anisotropies and pulsar timing arrays
AU - Allen, Bruce
AU - Agarwal, Deepali
AU - Romano, Joseph D.
AU - Valtolina, Serena
N1 - Publisher Copyright: © 2024 authors.
PY - 2024/12/3
Y1 - 2024/12/3
N2 - Pulsar timing arrays (PTAs) hunt for gravitational waves (GWs) by searching for the correlations that GWs induce in the time-of-arrival residuals from different pulsars. If the GW sources are of astrophysical origin, then they are located at discrete points on the sky. However, PTA data are often modeled, and subsequently analyzed, via a "standard Gaussian ensemble."That ensemble is obtained in the limit of an infinite density of vanishingly weak, Poisson-distributed sources. In this paper, we move away from that ensemble, to study the effects of two types of "source anisotropy."The first (a), which is often called "shot noise,"arises because there are N discrete GW sources at specific sky locations. The second (b) arises because the GW source positions are not a Poisson process, for example, because galaxy locations are clustered. Here, we quantify the impact of (a) and (b) on the mean and variance of the pulsar-averaged Hellings and Downs correlation. For conventional PTA sources, we show that the effects of shot noise (a) are much larger than the effects of clustering (b).
AB - Pulsar timing arrays (PTAs) hunt for gravitational waves (GWs) by searching for the correlations that GWs induce in the time-of-arrival residuals from different pulsars. If the GW sources are of astrophysical origin, then they are located at discrete points on the sky. However, PTA data are often modeled, and subsequently analyzed, via a "standard Gaussian ensemble."That ensemble is obtained in the limit of an infinite density of vanishingly weak, Poisson-distributed sources. In this paper, we move away from that ensemble, to study the effects of two types of "source anisotropy."The first (a), which is often called "shot noise,"arises because there are N discrete GW sources at specific sky locations. The second (b) arises because the GW source positions are not a Poisson process, for example, because galaxy locations are clustered. Here, we quantify the impact of (a) and (b) on the mean and variance of the pulsar-averaged Hellings and Downs correlation. For conventional PTA sources, we show that the effects of shot noise (a) are much larger than the effects of clustering (b).
UR - http://www.scopus.com/inward/record.url?scp=85211072601&partnerID=8YFLogxK
U2 - 10.48550/arXiv.2406.16031
DO - 10.48550/arXiv.2406.16031
M3 - Article
AN - SCOPUS:85211072601
VL - 110
JO - Physical Review D
JF - Physical Review D
SN - 2470-0010
IS - 12
M1 - 123507
ER -