2016/01/18 by L. Levin, Lina Levin, Maura A. McLaughlin +30 · 2 citations
Physics and Astronomy · #Advanced Frequency and Time Standards #Astrophysics #Atomic and Subatomic Physics Research #Computational physics #Detector #Galaxy #Green Bank Telescope #Interstellar medium #Optics #Physics #Pulsar #Pulsars and Gravitational Waves Research #Scaling #Scattering #Scintillation #Telescope #Time of arrival #astro-ph.HE #astro-ph.IM
paper · pdf · doi:10.3847/0004-637x/818/2/166
14 pages, 5 figures, 3 tables. Accepted for publication in ApJ
arxiv created 2016/01/18 · openalex publication_date 2016/02/17 · arxiv updated 2016/03/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
ABSTRACT We report on an effort to extract and monitor interstellar scintillation parameters in regular timing observations collected for the North American Nanohertz Observatory for Gravitational Waves pulsar timing array. Scattering delays are measured by creating dynamic spectra for each pulsar and observing epoch of wide-band observations centered near 1500 MHz and carried out at the Green Bank Telescope and the Arecibo Observatory. The ∼800 MHz wide frequency bands imply dramatic changes in scintillation bandwidth across the bandpass, and a stretching routine has been included to account for this scaling. For most of the 10 pulsars for which the scaling has been measured, the bandwidths scale with frequency less steeply than expected for a Kolmogorov medium. We find estimated scattering delay values that vary with time by up to an order of magnitude. The mean measured scattering delays are similar to previously published values and are slightly higher than predicted by interstellar medium models. We investigate the possibility of increasing the timing precision by mitigating timing errors introduced by the scattering delays. For most of the pulsars, the uncertainty in the time of arrival of a single timing point is much larger than the maximum variation of the scattering delay, suggesting that diffractive scintillation remains as only a negligible part of their noise budget.