PSR J0740+6620 is a neutron star in a binary system with a white dwarf, located 4,600 light years away in the Milky Way galaxy. It was discovered in 2019, by astronomers using the Green Bank Telescope in West Virginia, U.S., and confirmed as a rapidly rotating millisecond pulsar.
 Schematic of a pulsar | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Camelopardalis |
| Right ascension | 07h 40m 45.799s[1] |
| Declination | +66° 20′ 33.60″[1] |
| Characteristics | |
| Evolutionary stage | Pulsar |
| Details | |
| Mass | 2.08 M☉ |
| Radius | 13-15.1 km R☉ |
| Other designations | |
3FGL J0740.8+6621, 4FGL J0741.0+6618 | |
| Database references | |
| SIMBAD | data |
It is among the most massive neutron stars ever observed – with 2.08+0.07
−0.07 M☉[2][3][4] placing it near the boundary of the theoretical maximum.[5] Its mass was calculated via the Shapiro delay of its white dwarf companion as it passed edge-on to Earth. It was the record holder for the heaviest NS until July 2022 when the title was taken by PSR J0952–0607 with a reported mass of 2.35+0.17
−0.17 M☉.[6][7]
PSR J0740+6620 is estimated to measure 12.39+1.30
−0.98 km (7.70+0.81
−0.61 mi).[8][9][10]
See also
editReferences
edit- ^ a b "PSR J0740+6620". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-10-23.
- ^ Fonseca, E.; Cromartie, H. T.; Pennucci, T. T.; Ray, P. S.; Kirichenko, A. Yu; Ransom, S. M.; Demorest, P. B.; Stairs, I. H.; Arzoumanian, Z.; Guillemot, L.; Parthasarathy, A. (1 July 2021). "Refined Mass and Geometric Measurements of the High-mass PSR J0740+6620". The Astrophysical Journal Letters. 915 (1): L12. arXiv:2104.00880. Bibcode:2021ApJ...915L..12F. doi:10.3847/2041-8213/ac03b8. ISSN 2041-8205. S2CID 233004363.
- ^ Kohler, Susanna (16 August 2021). "Reweighing a Heavy Neutron Star". Retrieved 2021-08-20.
- ^ Cromartie, H. T.; Fonseca, E.; Ransom, S. M.; et al. (2019). "Relativistic Shapiro delay measurements of an extremely massive millisecond pulsar". Nature Astronomy. 4: 72–76. arXiv:1904.06759. Bibcode:2020NatAs...4...72C. doi:10.1038/s41550-019-0880-2. S2CID 118647384.
- ^ Green Bank Observatory (September 16, 2019). "Most massive neutron star ever detected, almost too massive to exist". ScienceDaily. Retrieved September 26, 2019.
- ^ Croswell, Ken (2022-07-22). "The heaviest neutron star on record is 2.35 times the mass of the sun". Science News. Retrieved 2022-07-25.
- ^ Romani, Roger W.; Kandel, D.; Filippenko, Alexei V.; Brink, Thomas G.; Zheng, WeiKang (2022-07-11). "PSR J0952−0607: The Fastest and Heaviest Known Galactic Neutron Star". The Astrophysical Journal Letters. 934 (2): L17. arXiv:2207.05124. Bibcode:2022ApJ...934L..17R. doi:10.3847/2041-8213/ac8007. S2CID 250451299.
- ^ Riley T, et al. (14 May 2021). "A NICER View of the Massive Pulsar PSR J0740+6620 Informed by Radio Timing and XMM-Newton Spectroscopy". The Astrophysical Journal Letters. 918 (2): L27. arXiv:2105.06980. Bibcode:2021ApJ...918L..27R. doi:10.3847/2041-8213/ac0a81. S2CID 234679649.
- ^ Kazmierczak J (19 April 2021). "NASA's NICER Probes the Squeezability of Neutron Stars". NASA.
- ^ O'Callaghan J (26 May 2021). "Squishy Neutron Star Setback Dampens Hopes of Exotic Matter". Quanta Magazine.
External links
edit- Susanna Kohler (15 September 2021). "More Insight into Neutron Star Interiors". AASnova.
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