Precision Pulsar Timing in the Presence of Interstellar Weather – PSR B1937+21 and the Crab Pulsar
Open Access
- 1 January 1996
- journal article
- other
- Published by Cambridge University Press (CUP) in International Astronomical Union Colloquium
- Vol. 160, 87-90
- https://doi.org/10.1017/s0252921100041099
Abstract
We report on six months of dual-frequency, precision timing of PSR B1937+21 and the Crab pulsar. Variations in the column density of electrons – interstellar weather – are studied. The column is not unique in the presence of frequency-dependent multipath scattering, and this may explain the non-square law dependence of systematic timing residuals on B1937+21. The electron column density variations of the Crab pulsar are summarized in a structure function that ranges from 1012cm to 1015cm. These density fluctuations are located in the thermal shell surrounding the synchrotron nebula.Keywords
This publication has 4 references indexed in Scilit:
- Three-Dimensional Fabry-Perot Imaging Spectroscopy of the Crab Nebula, Cassiopeia A, and Nova GK PerseiThe Astronomical Journal, 1995
- High-precision timing of millisecond pulsars. 3: Long-term monitoring of PSRs B1855+09 and B1937+21The Astrophysical Journal, 1994
- Temporal variations of pulsar dispersion measuresThe Astrophysical Journal, 1993
- Timing of the Crab Pular III. The Slowing Down and the Nature of the Random ProcessThe Astrophysical Journal Supplement Series, 1975