Paper: astro-ph/0509031
Date: Thu, 1 Sep 2005 20:02:23 GMT (51kb)

Title: Getting Its Kicks: A VLBA Parallax for the Hyperfast Pulsar B1508+55

Authors: S. Chatterjee (1), W. H. T. Vlemmings (2 and 3), W. F. Brisken (4), T.
J. W. Lazio (5), J. M. Cordes (3), W. M. Goss (4), S. E. Thorsett (6), E. B.
Fomalont (7), A. G. Lyne (2), M. Kramer (2) ((1) NRAO and CfA, (2) Jodrell
Bank, (3) Cornell, (4) NRAO Socorro, (5) NRL, (6) UC Santa Cruz, (7) NRAO
Charlottesville)

Comments: 5 pages, including 2 figures; accepted by ApJL; associated NRAO press
release at http://www.nrao.edu/pr/2005/fastpulsar/
Journal-ref: Astrophys.J. 630 (2005) L61-L64
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The highest velocity neutron stars establish stringent constraints on natal
kicks, asymmetries in supernova core collapse, and the evolution of close
binary systems. Here we present the first results of a long-term pulsar
astrometry program using the VLBA. We measure a proper motion and parallax for
the pulsar B1508+55, leading to model-independent estimates of its distance
(2.37+0.23-0.20 kpc) and transverse velocity (1083+103-90 km/s), the highest
velocity directly measured for a neutron star. We trace the pulsar back from
its present Galactic latitude of 52.3 degrees to a birth site in the Galactic
plane near the Cyg OB associations, and find that it will inevitably escape the
Galaxy. Binary disruption alone is insufficient to impart the required birth
velocity, and a natal kick is indicated. A composite scenario including a large
kick along with binary disruption can plausibly account for the high velocity.

\\ ( http://arXiv.org/abs/astro-ph/0509031 , 51kb)