1998/06/19 by Bing Zhang, Zhang, Bing, G. J. Qiao +1
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysics (astro-ph) #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #High-pressure geophysics and materials #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9806262
7 pages, 3 Postscript figures, LaTex, accepted for publication in Astronomy and Astrophysics
arxiv created 1998/06/19 · openalex publication_date 1998/06/19 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The importance of the photon-photon pair production process (γ+ γ′→ e++e-) to form pair production cascades in pulsar polar caps is investigated within the framework of the Ruderman-Sutherland vacuum gap model. It is found that this process is unimportant if the polar caps are not hot enough, but will play a non-negligible role in the pair formation cascades when the polar cap temperatures are in excess of the critical temperatures, Tcri, which are around 4× 106K when P=0.1s and will slowly increase with increasing periods. Compared with the γ-B process, it is found that the two-photon annihilation process may ignite a central spark near the magnetic pole, where γ-B sparks can not be formed due to the local weak curvatures. This central spark is large if the gap is dominated by the ``resonant ICS mode''. The possible connection of these central sparks with the observed pulsar ``core'' emission components is discussed.