Using the VLBA we have determined the parallax of the radio pulsar PSR B0656+14 to be π = 3.47±0.36 mas, yielding a distance of 288 -27+33 pc. This constrains existing models of thermal X-ray emission from the neutron star's photosphere yielding R∞ ∼7-8.5 km for simple blackbody models, and radii between ∼13 and ∼20 km with more realistic fits to a magnetized hydrogen atmosphere. Astrometric and age constrains argue in favor of a definite association with the Monogem Ring SNR. The latter's distance and age are consistent with the predictions of a model for the primary cosmic ray energy spectrum in which the 'knee' feature is produced by a single dominant source.
|Original language||English (US)|
|Number of pages||4|
|State||Published - Dec 1 2005|
- Cosmic rays
- ISM: supernova remnants, individual: Monogem Ring
- Pulsars: individual: PSR b0656+14