Observations of radio pulses from CU Virginis
Abstract
The magnetic chemically peculiar star CU Virginis is a unique astrophysical laboratory for stellar magnetospheres and coherent emission processes. It is the only known main-sequence star to emit a radio pulse every rotation period. Here we report on new observations of the CU Virginis pulse profile in the 13- and 20-cm radio bands. The profile is known to be characterized by two peaks of 100 per cent circularly polarized emission that are thought to arise in an electron–cyclotron maser mechanism. We find that the trailing peak is stable at both 13 and 20 cm, whereas the leading peak is intermittent at 13 cm. Our measured pulse arrival times confirm the discrepancy previously reported between the putative stellar rotation rates measured with optical data and with radio observations. We suggest that this period discrepancy might be caused by an unknown companion or by instabilities in the emission region. Regular long-term pulse timing and simultaneous multiwavelength observations are essential to clarify the behaviour of this emerging class of transient radio source.
Additional Information
© 2010 The Authors. Journal compilation © 2010 RAS. Accepted 2010 August 19. Received 2010 August 10; in original form 2010 July 6. We thank the referee, Ian Stevens, for many valuable suggestions. We are also grateful for the advice and insight of C. Trigilio on this Letter. The Australia Telescope Compact Array is part of the Australia Telescope which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. This research has made use of the SIMBAD data base, operated at CDS, Strasbourg, France. GH is supported by an Australian Research Council QEII Fellowship (project #DP0878388).Attached Files
Published - 408-1-L99.pdf
Accepted Version - 1008.3592.pdf
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Additional details
- Eprint ID
- 96737
- Resolver ID
- CaltechAUTHORS:20190626-121728326
- Commonwealth of Australia
- DP0878388
- Australian Research Council
- Created
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2019-06-26Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field