The stochastic gravitational-wave background is a superposition of sources that are either too weak or too numerous to detect individually. In this study, we present the results from a cross-correlation analysis on data from Advanced LIGO's second observing run (O2), which we combine with the results of the first observing run (O1). We do not find evidence for a stochastic background, so we place upper limits on the normalized energy density in gravitational waves at the 95% credible level of Omega(GW) < 6.0 x 10(-8) for a frequency-independent (flat) background and Omega(GW) < 4.8 x 10(-8) at 25 Hz for a background of compact binary coalescences. The upper limit improves over the O1 result by a factor of 2.8. Additionally, we place upper limits on the energy density in an isotropic background of scalar- and vector-polarized gravitational waves, and we discuss the implication of these results for models of compact binaries and cosmic string backgrounds. Finally, we present a conservative estimate of the correlated broadband noise due to the magnetic Schumann resonances in O2, based on magnetometer measurements at both the LIGO Hanford and LIGO Livingston observatories. We find that correlated noise is well below the O2 sensitivity.

Search for the isotropic stochastic background using data from Advanced LIGO's second observing run

Trovato A;
2019-01-01

Abstract

The stochastic gravitational-wave background is a superposition of sources that are either too weak or too numerous to detect individually. In this study, we present the results from a cross-correlation analysis on data from Advanced LIGO's second observing run (O2), which we combine with the results of the first observing run (O1). We do not find evidence for a stochastic background, so we place upper limits on the normalized energy density in gravitational waves at the 95% credible level of Omega(GW) < 6.0 x 10(-8) for a frequency-independent (flat) background and Omega(GW) < 4.8 x 10(-8) at 25 Hz for a background of compact binary coalescences. The upper limit improves over the O1 result by a factor of 2.8. Additionally, we place upper limits on the energy density in an isotropic background of scalar- and vector-polarized gravitational waves, and we discuss the implication of these results for models of compact binaries and cosmic string backgrounds. Finally, we present a conservative estimate of the correlated broadband noise due to the magnetic Schumann resonances in O2, based on magnetometer measurements at both the LIGO Hanford and LIGO Livingston observatories. We find that correlated noise is well below the O2 sensitivity.
2019
Pubblicato
File in questo prodotto:
File Dimensione Formato  
O2_Isotropic_12.pdf

accesso aperto

Tipologia: Documento in Pre-print
Licenza: Digital Rights Management non definito
Dimensione 4.52 MB
Formato Adobe PDF
4.52 MB Adobe PDF Visualizza/Apri
PhysRevD.100.061101.pdf

accesso aperto

Tipologia: Documento in Versione Editoriale
Licenza: Digital Rights Management non definito
Dimensione 811.88 kB
Formato Adobe PDF
811.88 kB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11368/3003294
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 248
  • ???jsp.display-item.citation.isi??? 124
social impact