Uncovering gravitational-wave backgrounds from noises of unknown shape with LISA
Detecting stochastic background radiation of cosmological origin is an exciting possibility for current and future gravitational-wave (GW) detectors. However, distinguishing it from other stochastic processes, such as instrumental noise and astrophysical backgrounds, is challenging. It is even more...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
26 April 2023
|
| In: |
Journal of cosmology and astroparticle physics
Year: 2023, Issue: 4, Pages: 1-28 |
| ISSN: | 1475-7516 |
| DOI: | 10.1088/1475-7516/2023/04/066 |
| Online Access: | Verlag, kostenfrei, Volltext: https://doi.org/10.1088/1475-7516/2023/04/066 Verlag, kostenfrei, Volltext: https://dx.doi.org/10.1088/1475-7516/2023/04/066 
|
| Author Notes: | Quentin Baghi, Nikolaos Karnesis, Jean-Baptiste Bayle, Marc Besançon and Henri Inchauspé |
| Summary: | Detecting stochastic background radiation of cosmological origin is an exciting possibility for current and future gravitational-wave (GW) detectors. However, distinguishing it from other stochastic processes, such as instrumental noise and astrophysical backgrounds, is challenging. It is even more delicate for the space-based GW observatory LISA since it cannot correlate its observations with other detectors, unlike today's terrestrial network. Nonetheless, with multiple measurements across the constellation and high accuracy in the noise level, detection is still possible. In the context of GW background detection, previous studies have assumed that instrumental noise has a known, possibly parameterized, spectral shape. To make our analysis robust against imperfect knowledge of the instrumental noise, we challenge this crucial assumption and assume that the single-link interferometric noises have an arbitrary and unknown spectrum. We investigate possible ways of separating instrumental and GW contributions by using realistic LISA data simulations with time-varying arms and second-generation time-delay interferometry. By fitting a generic spline model to the interferometer noise and a power-law template to the signal, we can detect GW stochastic backgrounds up to energy density levels comparable with fixed-shape models. We also demonstrate that we can probe a region of the GW background parameter space that today's detectors cannot access. |
|---|---|
| Item Description: | Gesehen am 20.06.2023 |
| Physical Description: | Online Resource |
| ISSN: | 1475-7516 |
| DOI: | 10.1088/1475-7516/2023/04/066 |