Open AccessBlack widow pulsars: the price of promiscuity
Author(s) -
King A. R.,
Davies M. B.,
Beer M. E.
Publication year - 2003
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2003.06990.x
Subject(s) - millisecond pulsar , globular cluster , physics , astrophysics , astronomy , pulsar , white dwarf , cluster (spacecraft) , population , millisecond , observable , stars , demography , quantum mechanics , sociology , computer science , programming language
The incidence of evaporating ‘black widow’ pulsars (BWPs) among all millisecond pulsars is far higher in globular clusters than in the field. This implies a special formation mechanism for them in clusters. Cluster millisecond pulsars in wide binaries with white dwarf companions exchange them for turnoff‐mass stars. These new companions eventually overflow their Roche lobes because of encounters and tides. The millisecond pulsars eject the overflowing gas from the binary, giving mass loss on the binary evolution time‐scale. The systems are only observable as BWPs at epochs where this evolution is slow, making the mass loss transparent and the lifetime long. This explains why observed BWPs have low‐mass companions. We suggest that at least some field BWPs were ejected from globular clusters or entered the field population when the cluster itself was disrupted.