Probing anisotropies of the Stochastic Gravitational Wave Background with LISA

Journal Article · Tue Nov 08 00:00:00 EST 2022 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2022/11/009· OSTI ID:2420028

Bartolo, Nicola ^[1]; Bertacca, Daniele ^[2]; Caldwell, Robert ^[3]; Contaldi, Carlo R. ^[4]; Cusin, Giulia ^[5]; De Luca, Valerio ^[5]; Dimastrogiovanni, Emanuela ^[6]; Fasiello, Matteo ^[7]; Figueroa, Daniel G. ^[8]; Franciolini, Gabriele ^[9]; Jenkins, Alexander C. ^[10]; Peloso, Marco ^[11]; Pieroni, Mauro ^[4]; Renzini, Arianna ^[12]; Ricciardone, Angelo ^[11]; Riotto, Antonio ^[5]; Sakellariadou, Mairi ^[13]; Sorbo, Lorenzo ^[14]; Tasinato, Gianmassimo ^[15]; Torrado, Jesús ^[16] ; Clesse, Sebastien ^[17]; Kuroyanagi, Sachiko ^[18]

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1. University of Padua (Italy); Istituto Nazionale di Fisica Nucleare (INFN) (Italy); Istituto Nazionale di Astrofisica (INAF), Firenze (Italy); Universit` a degli Studi di Padova, via Marzolo, Padova (Italy)
2. University of Padua (Italy); Istituto Nazionale di Fisica Nucleare (INFN) (Italy); Istituto Nazionale di Astrofisica (INAF), Firenze (Italy)
3. Dartmouth College, Hanover, NH (United States)
4. Imperial College, London (United Kingdom)
5. Univ. of Geneva (Switzerland)
6. Univ. of Groningen (Netherlands); Univ. of New South Wales, Sydney, NSW (Australia)
7. Spanish National Research Council (CSIC), Madrid (Spain); Univ. of Portsmouth (United Kingdom)
8. Spanish National Research Council (CSIC) (Spain); Univ. of Valencia (Spain)
9. Univ. of Rome (Italy); Istituto Nazionale di Fisica Nucleare (INFN) (Italy)
10. Univ. College London (United Kingdom); King's College, London (United Kingdom)
11. University of Padua (Italy); Istituto Nazionale di Fisica Nucleare (INFN) (Italy)
12. California Institute of Technology (CalTech), Pasadena, CA (United States)
13. King's College, London (United Kingdom)
14. Univ. of Massachusetts, Amherst, MA (United States)
15. Swansea University (United Kingdom)
16. RWTH Aachen Univ. (Germany)
17. Univ. Libre, Brussels (Belgium)
18. Spanish National Research Council (CSIC), Madrid (Spain)

Here, we investigate the sensitivity of the Laser Interferometer Space Antenna (LISA) to the anisotropies of the Stochastic Gravitational Wave Background (SGWB). We first discuss the main astrophysical and cosmological sources of SGWB which are characterized by anisotropies in the GW energy density, and we build a Signal-to-Noise estimator to quantify the sensitivity of LISA to different multipoles. We then perform a Fisher matrix analysis of the prospects of detectability of anisotropic features with LISA for individual multipoles, focusing on a SGWB with a power-law frequency profile. We compute the noise angular spectrum taking into account the specific scan strategy of the LISA detector. We analyze the case of the kinematic dipole and quadrupole generated by Doppler boosting an isotropic SGWB. We find that β Ω_GW ~ 2 × 10^-11 is required to observe a dipolar signal with LISA. The detector response to the quadrupole has a factor ~ 10³ β relative to that of the dipole. The characterization of the anisotropies, both from a theoretical perspective and from a map-making point of view, allows us to extract information that can be used to understand the origin of the SGWB, and to discriminate among distinct superimposed SGWB sources.

• Research Organization: Dartmouth College, Hanover, NH (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Contributing Organization: LISA Cosmology Working Group
• Grant/Contract Number: SC0010386
• OSTI ID: 2420028
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 11 Vol. 2022; ISSN 1475-7516
• Publisher: Institute of Physics (IOP)
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
gravitational wave detectors
gravitational waves / theory
gravitational waves / sources
physics of the early universe