Abstract
We have used the Giant Meterwave Radio Telescope (GMRT) to measure the Galactic HI 21-cm line absorption towards 102 extragalactic radio continuum sources, located at high (|b| > 15°) Galactic latitudes. The Declination coverage of the present survey is δ}> - 45°. With a mean rms optical depth of ∼ 0.003, this is the most sensitive Galactic HI 21-cm line absorption survey to date. To supplement the absorption data, we have extracted the HI 21-cm line emission profiles towards these 102 lines of sight from the Leiden Dwingeloo Survey of Galactic neutral hydrogen. We have carried out a Gaussian fitting analysis to identify the discrete absorption and emission components in these profiles. In this paper, we present the spectra and the components. A subsequent paper will discuss the interpretation of these results.
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Mohan, R., Dwarakanath, K.S. & Srinivasan, G. A high galactic latitude HI 21 cm-line absorption survey using the GMRT: I. Observations and spectra. J Astrophys Astron 25, 143–183 (2004). https://doi.org/10.1007/BF02702370
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DOI: https://doi.org/10.1007/BF02702370