0 The Proper Motion , Parallax , and Origin of the Isolated Neutron Star RX J 185635 - 3754
نویسنده
چکیده
The isolated neutron star RX J185635-3754 is the closest known neutron star to the Sun. Based on HST WFPC2 obervations over a 3 year baseline, I report its proper motion (332±1 mas yr at a position angle of 100.3±0.1) and parallax (16.5±2.3 mas; 61 pc). This proper motion brings the neutron star from the general vicinity of the Sco-Cen OB association. For an assumed neutron star radial velocity of –45 km s, the runaway O star ζ Oph, the Upper Sco OB association, and the neutron star come into spatial coincidence 1.15 ± .15 million years ago. RX J185635-3754 may be the remnant of the original primary of the ζ Oph system. If so, the space velocity suggests that the neutron star received a kick of about 200 km s at birth. Subject headings: stars: neutron; stars: individual (RX J185635-3754); stars: kinematics; open clusters and associations: Sco-Cen
منابع مشابه
0 The Proper Motion , Parallax , and Origin of the Isolated Neutron
The isolated neutron star RX J185635-3754 is the closest known neutron star to the Sun. Based on HST WFPC2 obervations over a 3 year baseline, I report its proper motion (332±1 mas yr at a position angle of 100.3±0.1) and parallax (16.5±2.3 mas; 61 pc). This proper motion brings the neutron star from the general vicinity of the Sco-Cen OB association. For an assumed neutron star radial velocity...
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