Title:	Narrow-band search of continuous gravitational-wave signals from Crab and Vela pulsars in Virgo VSR4 data
Authors:	Aasi, J. Abbott, B.P. Abbott, R. Iyer, B.R. LIGO Scientific Collaboration and Virgo Collaboration +842 Co authors
Issue Date:	15-Jan-2015
Publisher:	American Physical Society
Citation:	Physical Review D, 2015, Vol.91, p 022004
Abstract:	In this paper we present the results of a coherent narrow-band search for continuous gravitational-wave signals from the Crab and Vela pulsars conducted on Virgo VSR4 data. In order to take into account a possible small mismatch between the gravitational-wave frequency and two times the star rotation frequency, inferred from measurement of the electromagnetic pulse rate, a range of 0.02 Hz around two times the star rotational frequency has been searched for both the pulsars. No evidence for a signal has been found and 95% confidence level upper limits have been computed assuming both that polarization parameters are completely unknown and that they are known with some uncertainty, as derived from x-ray observations of the pulsar wind torii. For Vela the upper limits are comparable to the spin-down limit, computed assuming that all the observed spin-down is due to the emission of gravitational waves. For Crab the upper limits are about a factor of 2 below the spin-down limit, and represent a significant improvement with respect to past analysis. This is the first time the spin-down limit is significantly overcome in a narrow-band search.
Description:	Open Access
URI:	http://hdl.handle.net/2289/6156
ISSN:	1550-7998 1550-2368(Online)
Alternative Location:	http://arxiv.org/abs/1410.8310 http://dx.doi.org/10.1103/PhysRevD.91.022004 http://adsabs.harvard.edu/abs/2014arXiv1410.8310T
Copyright:	2015 American Physical Society
Appears in Collections:	Research Papers (TP)

Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.