Interstellar scintillation and polarization of PSR B0656+14 in the Monogem Ring

Abstract

High sensitivity interstellar scintillation and polarization observations of PSR~B0656+14 made at three epochs over a year using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) show that the scattering is dominated by two different compact regions. We identify the one nearer to the pulsar with the shell of the Monogem Ring, thereby confirming the association. The other is probably associated with the Local Bubble. We find that the observed position angles of the pulsar spin axis and the space velocity are significantly different, with a separation of $19\fdg3\pm$0\fdg8, inconsistent with a previously published near-perfect alignment of $1\degr\pm 2\degr$. The two independent scattering regions are clearly defined in the secondary spectra which show two strong forward parabolic arcs. The arc curvatures imply that the scattering screens corresponding to the outer and inner arcs are located approximately 28~pc from PSR B0656+14 and 185~pc from the Earth, respectively. Comparison of the observed Doppler profiles with electromagnetic simulations shows that both scattering regions are mildly anisotropic. For the outer arc, we estimate the anisotropy $A_R$ to be approximately 1.3, with the scattering irregularities aligned parallel to the pulsar velocity. For the outer arc, we compare the observed delay profiles with delay profiles computed from a theoretical strong-scattering model. Our results suggest that the spatial spectrum of the scattering irregularities in the Monogem Ring is flatter than Kolmogorov, but further observations are required to confirm this.

21 pages, 11 figures, accepted for publication in the Astronomical Journal

References in corpus (11)

• Science With The Australian Square Kilometre Array Pathfinder
• Calibrating High-Precision Faraday Rotation Measurements for LOFAR and the Next Generation of Low-Frequency Radio Telescopes
• Low-frequency Faraday rotation measures towards pulsars using LOFAR: probing the 3-D Galactic halo magnetic field
• Supernova Fallback as Origin of Neutron Star Spins and Spin-kick Alignment
• Evidence for alignment of the rotation and velocity vectors in pulsars. II. Further data and emission heights
• Modelling annual and orbital variations in the scintillation of the relativistic binary PSR J1141$-$6545
• The bright spiky emission of pulsar B0656+14
• Interstellar Scintillation of the Double Pulsar J0737$-$3039
• Spin-Kick Correlation in Neutron Stars: Alignment Conditions and Implications
• The low-frequency characteristics of PSR J0437-4715 observed with the Murchison Widefield Array
• Detection of strong scattering close to the eclipse region of PSR B1957+20

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• PHECT: A lightweight computation tool for pulsar halo emission
• Constraining the Pulsar 3D Velocity Distribution: The Impact of Spin-Velocity Alignment