X-ray emission from PSR B1800-21, its wind nebula, and similar systems
Abstract
We detected X-ray emission from PSR B1800-21 and its synchrotron nebula with the Chandra X-ray Observatory. The pulsar's observed flux is (1.4+/-0.2) 10-14 ergs cm-2 s-1 in the 1-6 keV band. The spectrum can be described by a two-component PL+BB model, suggesting a mixture of thermal and magnetospheric emission. For a plausible hydrogen column density nH=1.4 1022 cm-2, the PL component has a slope Gamma=1.4+/-0.6 and a luminosity Lpsrnonth=4 1031(d/4 kpc)2 ergs s-1. The properties of the thermal component (kT=0.1-0.3 keV, Lbol=1031-1033 ergs s-1) are very poorly constrained because of the strong interstellar absorption. The compact, 7''×4'', inner pulsar-wind nebula (PWN), elongated perpendicular to the pulsar's proper motion, is immersed in a fainter asymmetric emission. The observed flux of the PWN is (5.5+/-0.6) 10-14 ergs cm-2 s-1 in the 1-8 keV band. The PWN spectrum fits by a PL model with Gamma=1.6+/-0.3, L=1.6 1032 (d/4 kpc)2 ergs s-1. The shape of the inner PWN suggests that the pulsar moves subsonically and X-ray emission emerges from a torus associated with the termination shock in the equatorial pulsar wind. The inferred PWN-pulsar properties (e.g., the PWN X-ray efficiency, Lpwn/E~10-4; the luminosity ratio, Lpwn/Lpsrnonth=4; the pulsar wind pressure at the termination shock, ps=10-9 ergs cm-3) are very similar to those of other subsonically moving Vela-like objects detected with Chandra (Lpwn/E=10-4.5-10-3.5, Lpwn/Lpsrnonth~5, ps=10-10-10-8 ergs cm-1).
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.