Document Type
Article
Department/Program
Physics
Journal Title
Physical Review D
Pub Date
2015
Volume
91
Issue
2
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.
Recommended Citation
Aasi, J.; Abbott, B. P.; Abbott, R.; Mikhailov, E. E.; Romanov, G.; and Zhang, M., Narrow-band search of continuous gravitational-wave signals from Crab and Vela pulsars in Virgo VSR4 data (2015). Physical Review D, 91(2).
10.1103/PhysRevD.91.022004
DOI
10.1103/PhysRevD.91.022004
