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arXiv · 1501.05401

Scatter broadening measurements of 124 pulsars at 327 MHz

M. A. Krishnakumar·Dipanjan Mitra·Arun Naidu·Bhal Chandra Joshi·P. K. Manoharan
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Abstract

We present the measurements of scatter broadening time-scales ($τ_{sc}$) for 124 pulsars at 327 MHz, using the upgraded Ooty Radio Telescope (ORT). These pulsars lie in the dispersion measure range of 37 $-$ 503 pc cm$^{-3}$ and declination ($δ$) range of $-$57$^{\circ} < δ< 60^{\circ}$. New $τ_{sc}$ estimates for 58 pulsars are presented, increasing the sample of all such measurements by about 40% at 327 MHz. Using all available $τ_{sc}$ measurements in the literature, we investigate the dependence of $τ_{sc}$ on dispersion measure. Our measurements, together with previously reported values for $τ_{sc}$, affirm that the ionized interstellar medium upto 3 kpc is consistent with Kolmogorov spectrum, while it deviates significantly beyond this distance.

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M. A. Krishnakumar, Dipanjan Mitra, Arun Naidu, Bhal Chandra Joshi, P. K. Manoharan. 2015-01-22. Scatter broadening measurements of 124 pulsars at 327 MHz. https://doi.org/10.1088/0004-637x%2F804%2F1%2F23

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