English

A High-Frequency Search for Pulsars Within the Central Parsec of SgrA*

Astrophysics of Galaxies 2015-05-18 v1

Abstract

We report results from a deep high-frequency search for pulsars within the central parsec of Sgr A* using the Green Bank Telescope. The observing frequency of 15 GHz was chosen to maximize the likelihood of detecting normal pulsars (i.e. with periods of 500\sim 500\,ms and spectral indices of 1.7\sim -1.7) close to Sgr A*, that might be used as probes of gravity in the strong-field regime; this is the highest frequency used for such pulsar searches of the Galactic Center to date. No convincing candidate was detected in the survey, with a 10σ10\sigma detection threshold of 10μ\sim 10 \muJy achieved in two separate observing sessions. This survey represents a significant improvement over previous searches for pulsars at the Galactic Center and would have detected a significant fraction ($\gtrsim 5%) of the pulsars around Sgr A*, if they had properties similar to those of the known population. Using our best current knowledge of the properties of the Galactic pulsar population and the scattering material toward Sgr A*, we estimate an upper limit of 90 normal pulsars in orbit within the central parsec of Sgr A*.

Keywords

Cite

@article{arxiv.1004.1643,
  title  = {A High-Frequency Search for Pulsars Within the Central Parsec of SgrA*},
  author = {J-P. Macquart and N. Kanekar and D. Frail and S. Ransom},
  journal= {arXiv preprint arXiv:1004.1643},
  year   = {2015}
}

Comments

10 pages, 7 figures, accepted for publication in the ApJ.