2017/10/17 by G. G. Pavlov, George G. Pavlov, Blagoy Rangelov +8 · 40 citations
Engineering · Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Calibration and Measurement Techniques #Far ultraviolet #Nuclear Physics and Applications #Nuclear physics #Physics #Spectral line #astro-ph.HE
paper · pdf · doi:10.3847/1538-4357/aa947c
published in The Astrophysical Journal 850(1), 79 (IOP Publishing) · 9 pages, 5 figures. Accepted by the Astrophysical Journal
arxiv created 2017/10/17 · openalex created_date 2017/11/10 · openalex publication_date 2017/11/20 · arxiv updated 2017/12/06 · openalex updated_date 2026/08/06
Abstract We report on a Hubble Space Telescope detection of the nearby, old pulsar B0950+08 ( pc, spin-down age 17.5 Myr) in two far-ultraviolet (FUV) bands. We measured the mean flux densities nJy and 83 ± 14 nJy in the F125LP and F140LP filters (pivot wavelengths 1438 and 1528 Å). Using the FUV data together with previously obtained optical–UV data, we conclude that the optical–FUV spectrum consists of two components—a nonthermal (presumably magnetospheric) power-law spectrum ( ) with slope and a thermal spectrum emitted from the bulk of the neutron star (NS) surface with a temperature in the range of (1–3) × 10 5 K, depending on interstellar extinction and NS radius. These temperatures are much higher than predicted by NS cooling models for such an old pulsar, which means that some heating mechanisms operate in NSs. A plausible mechanism responsible for the high temperature of PSR B0950+08 is the interaction of vortex lines of the faster rotating neutron superfluid with the slower rotating normal matter in the inner NS crust (vortex creep heating).