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تسجيل مستخدم جديدSubaru optical observations of the old pulsar PSR B0950+08
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S. V. Zharikov
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We report the B band optical observations of an old (17.5 Myr) radiopulsar PSR B0950+08 obtained with the Suprime-Cam at the Subaru telescope. We detected a faint object, B=27.07(16). Within our astrometrical accuracy it coincides with the radio position of the pulsar and with the object detected earlier by Pavlov et al. (1996) in UV with the HST/FOC/F130LP. The positional coincidence and spectral properties of the object suggest that it is the optical counterpart of PSR B0950+08. Its flux in the B band is two times higher than one would expect from the suggested earlier Rayleigh-Jeans interpretation of the only available HST observations in the adjacent F130LP band. Based on the B and F130LP photometry of the suggested counterpart and on the available X-ray data we argue in favour of nonthermal origin of the broad-band optical spectrum of PSR B0950+08, as it is observed for the optical emission of the younger, middle-aged pulsars PSR B0656+14 and Geminga. At the same time, the optical efficiency of PSR B0950+08, estimated from its spin-down power and the detected optical flux, is by several orders of magnitude higher than for these pulsars, and comparable with that for the much younger and more energetic Crab pulsar. We cannot exclude the presence of a compact, about 1, faint pulsar nebula around PSR B0950+08, elongated perpendicular to the vector of its proper motion, unless it is not a projection of a faint extended object on the pulsar position.
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We report the detection of giant pulse emission from PSR B0950+08 in 24 hours of observations made at 39.4 MHz, with a bandwidth of 16 MHz, using the first station of the Long Wavelength Array, LWA1. We detected 119 giant pulses from PSR B0950+08 (at
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We report on a Hubble Space Telescope detection of the nearby, old pulsar B0950+08 ($dsimeq 262$ pc, spin-down age 17.5 Myr) in two far-ultraviolet (FUV) bands. We measured the mean flux densities $bar{f}_ u = 109pm 6$ nJy and $83pm 14$ nJy in the F1
25LP and F140LP filters (pivot wavelengths 1438 and 1528 AA). 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 ($f_ upropto u^alpha$) with slope $alphasim -1.2$ and a thermal spectrum emitted from the bulk of the neutron star surface with a temperature in the range of $(1-3)times 10^5$ K, depending on interstellar extinction and neutron star radius. These temperatures are much higher than predicted by neutron star cooling models for such an old pulsar, which means that some heating mechanisms operate in neutron stars. 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 neutron star crust (vortex creep heating).
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