High Frequency Radio Observations of the Reactivated Magnetar XTE J1810-197

ATel #12353; Walid A. Majid (JPL, Caltech), Aaron B. Pearlman (Caltech), Thomas A. Prince (Caltech, JPL), Shinji Horiuchi (CSIRO), Charles J. Naudet (JPL), Jonathon Kocz (Caltech), Teruaki Enoto (Kyoto University)
on 3 Jan 2019; 18:59 UT
Credential Certification: Walid Majid (majidw@gmail.com)

Tweet

Following a recent report of intense radio flaring of the magnetar XTE J1810-197 on 2018 December 8, detected with the Lovell telescope (Lyne et al., ATel #12284), a number of subsequent radio observations at various radio observatories have reported significant detections of pulsed emission. These reports include observations with the 100-m Effelsberg radio telescope at 4.74 and 8.35 GHz (Desvignes et al., ATel #12285), the Molonglo Observatory Synthesis Telescope at 835 MHz (Lower et al., ATel #12288), the upgraded GMRT at 550-750 MHz (Joshi et al., #ATel #12312), and the Argentinian Institute of Radioastronomy`s 30-m instrument at 1420 MHz (del Palacio et al., ATel #12323).

To obtain flux density estimates at still higher radio frequencies, we have carried out a 5.5 hour long observation of this magnetar on 2018 December 24 (MJD 58477.05623) using one of NASA`s Deep Space Network (DSN) 34-m dishes in Canberra, Australia. Right circular polarization data were recorded at center frequencies of 8.4 and 32 GHz, with roughly 500 MHz of bandwidth at each frequency band, using the JPL ultra-wideband pulsar machine.

We obtained significant detections of the pulsar at both frequency bands with mean flux densities of 4.0 +/- 0.8 mJy at 8.4 Hz and 1.7 +/- 0.3 mJy at 32 GHz, giving a spectral index of -0.7 +/- 0.2 over this wide frequency range. Our best estimate of the barycentric spin period and DM are 5.5414471(5) s and 178 +/- 9 pc cm**-3, respectively. The average pulse profiles were noticeably variable during this single observing epoch. We also detected bright, multi-component single pulses at both frequency bands throughout the observation.

Given the unique nature of this source, with the 2018 outburst being only the second such outburst in the last 10 years (Camilo et al. 2006; Camilo et al. 2016), further multi-frequency monitoring of this source is needed to study the behavior of the magnetar after the recent outburst.

We thank the DSN, CSIRO for providing Host Country Time, and the Canberra Deep Space Communication Complex (CDSCC) teams for supporting this observation. A portion of this research was performed at the Jet Propulsion Laboratory, California Institute of Technology and the Caltech campus, under a Research and Technology Development Grant through a contract with the National Aeronautics and Space Administration. U.S. government sponsorship is acknowledged. Copyright 2019. All rights reserved.

References:

Camilo, et al. 2006, Nature, 442, 892.

Camilo, et al. 2016, ApJ, 820, 110.