The Radius of PSR J0740+6620 from NICER and XMM-Newton Data

Miller, M. C. and Lamb, F. K. and Dittmann, A. J. and Bogdanov, S. and Arzoumanian, Z. and Gendreau, K. C. and Guillot, S. and Ho, W. C. G. and Lattimer, J. M. and Loewenstein, M. and Morsink, S. M. and Ray, P. S. and Wolff, M. T. and Baker, C. L. and Cazeau, T. and Manthripragada, S. and Markwardt, C. B. and Okajima, T. and Pollard, S. and Cognard, I. and Cromartie, H. T. and Fonseca, E. and Guillemot, L. and Kerr, M. and Parthasarathy, A. and Pennucci, T. T. and Ransom, S. and Stairs, I. (2021) The Radius of PSR J0740+6620 from NICER and XMM-Newton Data. The Astrophysical Journal Letters, 918 (2). L28. ISSN 2041-8205

[thumbnail of Miller_2021_ApJL_918_L28.pdf] Text
Miller_2021_ApJL_918_L28.pdf - Published Version

Download (6MB)

Abstract

PSR J0740+6620 has a gravitational mass of 2.08 ± 0.07 M⊙, which is the highest reliably determined mass of any neutron star. As a result, a measurement of its radius will provide unique insight into the properties of neutron star core matter at high densities. Here we report a radius measurement based on fits of rotating hot spot patterns to Neutron Star Interior Composition Explorer (NICER) and X-ray Multi-Mirror (XMM-Newton) X-ray observations. We find that the equatorial circumferential radius of PSR J0740+6620 is ${13.7}_{-1.5}^{+2.6}$ km (68%). We apply our measurement, combined with the previous NICER mass and radius measurement of PSR J0030+0451, the masses of two other ∼2 M⊙ pulsars, and the tidal deformability constraints from two gravitational wave events, to three different frameworks for equation-of-state modeling, and find consistent results at ∼1.5–5 times nuclear saturation density. For a given framework, when all measurements are included, the radius of a 1.4 M⊙ neutron star is known to ±4% (68% credibility) and the radius of a 2.08 M⊙ neutron star is known to ±5%. The full radius range that spans the ±1σ credible intervals of all the radius estimates in the three frameworks is 12.45 ± 0.65 km for a 1.4 M⊙ neutron star and 12.35 ± 0.75 km for a 2.08 M⊙ neutron star.

Item Type: Article
Subjects: Research Asian Plos > Physics and Astronomy
Depositing User: Unnamed user with email support@research.asianplos.com
Date Deposited: 11 May 2023 09:14
Last Modified: 21 Oct 2024 04:23
URI: http://abstract.stmdigitallibrary.com/id/eprint/762

Actions (login required)

View Item
View Item