TY - JOUR

T1 - Search for a stochastic gravitational-wave background with torsion-bar antennas

AU - Shoda, Ayaka

AU - Ando, Masaki

AU - Okada, Kenshi

AU - Ishidoshiro, Koji

AU - Kokuyama, Wataru

AU - Aso, Yoichi

AU - Tsubono, Kimio

PY - 2012

Y1 - 2012

N2 - We performed a simultaneous observational run with prototypes of Torsion-bar Antenna (TOBA) and searched for a stochastic gravitational waves (GW) background. TOBA is a new type of GW detector which measures differential rotation of two test-mass bars caused by tidal force from GWs. It fundamentally has a good sensitivity at lower frequencies, such as 0.1-1.0 Hz. The prototype has a 20-cm test mass bar which is levitated by the pinning effect of a superconductor. The data was taken from 1:00 am to 10:00 am on March 11th 2011, at Tokyo and Kyoto in Japan. As a result, we did not detect a stochastic GW background with false alarm rate of 5 %, and set an upper limit on a stochastic GW background. Our 95 % confidence upper limit is Ωgwh 20 < 1.2 × 1019 at 0.06 - 0.9 Hz, where Ωgw is the GW energy density per logarithmic frequency interval in units of the critical density and ho is the Hubble constant per 100 km/sec/Mpc. We had established the simultaneous observation and the analysis pipeline with two TOBAs, and set an upper limit at a wider frequency band.

AB - We performed a simultaneous observational run with prototypes of Torsion-bar Antenna (TOBA) and searched for a stochastic gravitational waves (GW) background. TOBA is a new type of GW detector which measures differential rotation of two test-mass bars caused by tidal force from GWs. It fundamentally has a good sensitivity at lower frequencies, such as 0.1-1.0 Hz. The prototype has a 20-cm test mass bar which is levitated by the pinning effect of a superconductor. The data was taken from 1:00 am to 10:00 am on March 11th 2011, at Tokyo and Kyoto in Japan. As a result, we did not detect a stochastic GW background with false alarm rate of 5 %, and set an upper limit on a stochastic GW background. Our 95 % confidence upper limit is Ωgwh 20 < 1.2 × 1019 at 0.06 - 0.9 Hz, where Ωgw is the GW energy density per logarithmic frequency interval in units of the critical density and ho is the Hubble constant per 100 km/sec/Mpc. We had established the simultaneous observation and the analysis pipeline with two TOBAs, and set an upper limit at a wider frequency band.

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U2 - 10.1088/1742-6596/363/1/012017

DO - 10.1088/1742-6596/363/1/012017

M3 - Conference article

AN - SCOPUS:84862337212

SN - 1742-6588

VL - 363

JO - Journal of Physics: Conference Series

JF - Journal of Physics: Conference Series

IS - 1

M1 - 012017

T2 - 9th Edoardo Amaldi Conference on Gravitational Waves, Amaldi 9 and the 2011 Numerical Relativity - Data Analysis Meeting, NRDA 2011

Y2 - 10 July 2011 through 15 July 2011

ER -