Detection of strong scattering close to the eclipse region of PSR B1957+20

• Published in: Monthly notices of the Royal Astronomical Society Vol. 513; no. 2; pp. 1794 - 1800
• Main Authors: Bai, J T, Dai, S, Zhi, Q J, Coles, W A, Li, D, Zhu, W W, Hobbs, G, Qiao, G J, Wang, N, Yuan, J P, Filipović, M D, Wang, J B, Pan, Z C, Shang, L H, Dang, S J, Wang, S Q, Miao, C C
• Format: Journal Article
• Language: English
• Published: Oxford University Press 03.05.2022
• Subjects: binaries: eclipsing; pulsars: individual: PSR B1957+20; scattering; pulsars: general
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stac918

ABSTRACT We present the first measurement of pulse scattering close to the eclipse region of PSR B1957+20, which is in a compact binary system with a low-mass star. We measured pulse scattering time-scales up to 0.2 ms close to the eclipse and showed that it scales with the dispersion measure (DM) excess roughly as τ ∝ ΔDM2. Our observations provide the first evidence of strong scattering due to multipath propagation effects in the eclipsing material. We show that Kolmogorov turbulence in the eclipsing material with an inner scale of ∼100 m and an outer scale of the size of the eclipse region can naturally explain the observation. Our results show that the eclipsing material in such systems can be highly turbulent and suggest that scattering is one of the main eclipsing mechanisms at around 1.4 GHz.