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The tiny-scale atomic structure: gas cloudlets or scintillation phenomenon ?

S. Stanimirovic·J. M. Weisberg·A. Hedden·K. Devine·T. Greent·S. B. Anderson
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Abstract

We present preliminary results from the recent multi-epoch HI absorption measurements toward several pulsars using the Arecibo telescope. We do not find significant variations in optical depth profiles over periods of 4 months and 9 years. The upper limits on the optical depth variations in directions of B0823+26 and B1133+16 are similar on scales of 10--20, 350 and 500 AU. The large number of non detections of the tiny scale atomic structure suggests that the AU-sized structure is not ubiquitous in the interstellar medium.

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S. Stanimirovic, J. M. Weisberg, A. Hedden, K. Devine, T. Greent, S. B. Anderson. 2003-06-30. The tiny-scale atomic structure: gas cloudlets or scintillation phenomenon ?. https://doi.org/10.1023/b%3Aastr.0000045005.36554.36

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