ChandraObservations of the Pulsar B1929+10 and Its Environment

Abstract

We report on two Chandra observations of the 3 Myr old pulsar B1929+10, which reveal a faint compact ($9 00 ; 5 00 ) nebula elongated in the direction perpendicular to the pulsar's proper motion, two patchy wings, and a possible short ($3 00 ) jet emerging from the pulsar. In addition, we detect a tail extending up to at least 4 0 in the direction opposite to the pulsar's proper motion, aligned with the $15 0 long tail detected in ROSAT and XMM-Newton observations. The overall morphology of the nebula suggests that the shocked pulsar wind is confined by the ram pressure due to the pulsar's supersonic speed. The shape of the compact nebula in the immediate vicinity of the pulsar seems to be consistent with the current MHD models. However, since these models do not account yet for the change of the flow velocity at larger distances from the pulsar, they are not able to constrain the extent of the long pulsar tail. The luminosity of the whole nebula as seen by Chandra is L PWN $ 10 30 ergs s À1 in the 0.3Y8 keV band, for the distance of 361 pc. Using the Chandra and XMM-Newton data, we found that the pulsar spectrum is composed of nonthermal (magnetospheric) and thermal components. The nonthermal component can be described by a power-law model with photon index À % 1:7 and luminosity L nonth PSR % 1:7 ; 10 30 ergs s À1 in the 0.3Y10 keV band. The blackbody fit for the thermal component, which presumably emerges from hot polar caps, gives the temperature kT % 0:3 keV and projected emitting area A ? $ 3 ; 10 3 m 2 , corresponding to the bolometric luminosity L bol $ (1Y2) ; 10 30 ergs s À1 .

The Radio and X-ray Mode-Switching Pulsar PSR B0943+10

“…PSR B0943+10 is thus similar to other old and middle aged pulsars from which thermal X-rays from a small emitting area have been detected (e.g. [34,35,36,37]). It is believed that the surface heating in these pulsars results from the flow of backward-accelerated particles produced in the star magnetosphere above the polar caps [32,38].…”

Simultaneous X-ray and radio observations of the radio-mode-switching pulsar PSR B1822−09

“…Old pulsars with their spectrum dominated by hot spot radiation show that an actual polar cap is considerably smaller than R dp , see e.g. PSR J0108−1431 (Pavlov et al 2009;Posselt et al 2012), PSR J0633+1746 (Kargaltsev et al 2005), PSR B1929+10 (Misanovic, Pavlov & Garmire 2008). Furthermore, the estimated magnetic field strengths at the polar cap for these pulsars (Bs ∼ 10 14 G) and temperatures of a few million Kelvin satisfy the condition for the formation of a Partially Screened Gap (PSG) (see Gil et al 2003;Medin & Lai 2007).…”

Instabilities, nulls and subpulse drift in radio pulsars

“…There have been many attempts to measure the polar‐cap blackbody temperature and source area of a subset of radio pulsars. We refer to Zavlin & Pavlov (2004) for B0950+08, De Luca et al (2005) for B0656+14 and B1055−52, Tepedelenlioğlu & Ögelman (2005) for B0628−28, Zhang, Sanwal & Pavlov (2005) for B0943+10, Kargaltsev, Pavlov & Garmire (2006) for B1133+16, Gil et al (2008) for B0834+06 and Misanovic, Pavlov & Garmire (2008) for B1929+10. Five pulsars (B0628−28, B0834+06, B0943+10, B1133+16, B1929+10) have source areas one or two orders of magnitude smaller than the canonical area, but unfortunately, a systematic comparison with equations ()–(42) is not possible because in most instances the authors are able to say only that the observed X‐ray spectrum is consistent with the stated temperature and source area.…”