PSR J2144-3933
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Grus |
Right ascension | 21h 44m 12.10s |
Declination | -39° 33' 55.2"' |
Characteristics | |
Spectral type | Pulsar |
U−B color index | ? |
B−V color index | ? |
Variable type | None |
Astrometry | |
Distance | 587.088 Ly (180 parsecs) |
Details | |
Mass | ? M☉ |
Radius | ? R☉ |
Luminosity | ? L☉ |
Temperature | ? K |
Metallicity | ? |
Rotation | 8.51 s |
Age | ? years |
Other designations | |
PSR J2144-3933 is a pulsar about 180 parsecs (5.5 Em) from Earth. It was previously thought to have a period of 2.84 seconds but is now known to have a period of 8.51 s, which is among the longest known radio pulsar.
J2144-3933 is notable for other reasons: its mean pulse profile is very narrow in comparison to the pulse period with a half-intensity width of less than one degree of longitude. It also has the lowest spindown luminosity of any pulsar at about 3×1021 watts.
Writing in Nature, astrophysicists M. D. Young and coworkers consider this object and suggest that its existence throws current theories into doubt. They state:
- Moreover, under the usual model assumptions, based on the neutron-star equations of state, this slowly rotating pulsar should not be emitting a radio beam. Therefore either the model assumptions are wrong, or current theories of radio emission must be revised[1]
References
- ↑ Young, M. D.; Manchester, R. N.; Johnston, S. (26 August 1999). "A radio pulsar with an 8.5-second period that challenges emission models". Nature (400): 848–849. Bibcode:1999Natur.400..848Y. doi:10.1038/23650.
External links
- http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=PSR+J2144-3933&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id
- ""Undead" Star Torpedoes Current Theories". Sciencedaily.com. 26 August 1999. Retrieved June 2013. Check date values in:
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(help) - Kohler, Susanna (25 March 2011). "A Pulsar Alone: The first deep X-ray and optical observations of the closest isolated radio pulsar". Astrobites.org. Retrieved June 2013. Check date values in:
|access-date=
(help)
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