Robust estimation of scattering in pulsar timing analysis

Lentati L, Kerr M, Dai S, Shannon RM, Hobbs G, Oslowski S (2017)
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 468(2): 1474-1485.

Download
No fulltext has been uploaded. References only!
Journal Article | Original Article | Published | English

No fulltext has been uploaded

Author
; ; ; ; ;
Abstract
We present a robust approach to incorporating models for the time-variable broadening of the pulse profile due to scattering in the ionized interstellar medium into profile-domain pulsar timing analysis. We use this approach to simultaneously estimate temporal variations in both the dispersion measure (DM) and scattering, together with a model for the pulse profile that includes smooth evolution as a function of frequency, and the pulsar's timing model. We show that fixing the scattering time-scales when forming time-of-arrival estimates, as has been suggested in the context of traditional pulsar timing analysis, can significantly underestimate the uncertainties in both DM and the arrival time of the pulse, leading to bias in the timing parameters. We apply our method using a new, publicly available, GPU-accelerated code, both to simulations and observations of the millisecond pulsar PSR J1643-1224. This pulsar is known to exhibit significant scattering variability compared to typical millisecond pulsars, and we find including low-frequency (< 1 GHz) data without a model for these scattering variations leads to significant periodic structure in the DM, and also biases the astrometric parameters at the 4 sigma level, for example, changing proper motion in right ascension by 0.50 +/- 0.12. If low-frequency observations are to be included when significant scattering variations are present, we conclude it is necessary to not just model those variations, but also to sample the parameters that describe the variations simultaneously with all other parameters in the model, a task for which profile domain pulsar timing is ideally suited.
Publishing Year
ISSN
eISSN
PUB-ID

Cite this

Lentati L, Kerr M, Dai S, Shannon RM, Hobbs G, Oslowski S. Robust estimation of scattering in pulsar timing analysis. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY. 2017;468(2):1474-1485.
Lentati, L., Kerr, M., Dai, S., Shannon, R. M., Hobbs, G., & Oslowski, S. (2017). Robust estimation of scattering in pulsar timing analysis. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 468(2), 1474-1485. doi:10.1093/mnras/stx580
Lentati, L., Kerr, M., Dai, S., Shannon, R. M., Hobbs, G., and Oslowski, S. (2017). Robust estimation of scattering in pulsar timing analysis. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 468, 1474-1485.
Lentati, L., et al., 2017. Robust estimation of scattering in pulsar timing analysis. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 468(2), p 1474-1485.
L. Lentati, et al., “Robust estimation of scattering in pulsar timing analysis”, MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, vol. 468, 2017, pp. 1474-1485.
Lentati, L., Kerr, M., Dai, S., Shannon, R.M., Hobbs, G., Oslowski, S.: Robust estimation of scattering in pulsar timing analysis. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY. 468, 1474-1485 (2017).
Lentati, L., Kerr, M., Dai, S., Shannon, R. M., Hobbs, G., and Oslowski, Stefan. “Robust estimation of scattering in pulsar timing analysis”. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 468.2 (2017): 1474-1485.
This data publication is cited in the following publications:
This publication cites the following data publications:

Export

0 Marked Publications

Open Data PUB

Web of Science

View record in Web of Science®

Search this title in

Google Scholar