On the radio quiescence of anomalous X-ray pulsars and soft gamma-ray repeaters

Authors
Citation
B. Zhang, On the radio quiescence of anomalous X-ray pulsars and soft gamma-ray repeaters, ASTROPHYS J, 562(1), 2001, pp. L59-L62
Citations number
26
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004-637X → ACNP
Volume
562
Issue
1
Year of publication
2001
Part
2
Pages
L59 - L62
Database
ISI
SICI code
0004-637X(20011120)562:1<L59:OTRQOA>2.0.ZU;2-S
Abstract
In the hot environments of the anomalous X-ray pulsars (AXPs) and the soft gamma-ray repeaters (SGRs), as indicated by their luminous, pulsed, quiesce nt X-ray emission, gamma rays generated from the inner gaps may have shorte r attenuation lengths via two-photon pair production rather than via magnet ic photon splitting. The AXP/SGR environments may not be pairless, even if photon splitting could completely suppress one-photon pair production in su perstrong magnetic fields, as conjectured by Baring and Harding. Two-photon pair production more likely occurs near the threshold, which tends to gene rate low-energy pairs that are not energetic enough to power radio emission in the observed bands. However, emission in longer wavelengths may not be prohibited, in principle, if these objects are indeed magnetars. The so-cal led photon-splitting deathlines are still valid for high magnetic field pul sars that are much dimmer in X-rays, if gamma rays with both polarization m odes split.