Starquakes in millisecond pulsars and gravitational waves emission

Giliberti, E. and Cambiotti(, G. (2022) Starquakes in millisecond pulsars and gravitational waves emission. Il nuovo cimento C, 45 (6). pp. 1-4. ISSN 1826-9885

Text ncc12562.pdf - Published Version Download (179kB)

Abstract

Accreting neutron stars (NSs) have long been considered potential continuous gravitational-wave (GW) emitters. Centrifugal forces in these rapidly rotating objects can be so strong to break the neutron star crust (causing starquakes), deforming the star in a non-axially symmetric way, leading to the emission of GWs. At equilibrium, the angular momentum gained by accretion and the one lost via GWs emission should balance each other, stopping the stellar spin-up. We investigate the above physical picture by modeling the NS as a Newtonian model describing compressible, non-magnetized and self-gravitating object. In particular, we calculate the rotational frequency necessary to break the crust and estimate an upper limit for the consequent ellipticity. Depending on the stellar mass and its equation of state, we find that the maximum starquake-induced ellipticity ranges from 10−9 to 10−5. Furthermore, the corresponding equilibrium frequency is below the higher NS frequency observed of 716.36 Hz for all the scenarios. Finally, we also discuss possible observational constraints on the ellipticity upper limit.

Item Type:	Article
Subjects:	500 Scienze naturali e Matematica > 530 Fisica
Depositing User:	Marina Spanti
Date Deposited:	20 Sep 2022 11:04
Last Modified:	20 Sep 2022 11:04
URI:	http://eprints.bice.rm.cnr.it/id/eprint/22112

Actions (login required)

View Item