A High Galactic Latitude HI 21 cm-line Absorption Survey using the GMRT: I. Observations and Spectra

Journal of astrophysics and astronomy

K. S. Dwarakanath1¹  Rekhesh Mohan1 2¹  G. Srinivasan1¹ 

[1] Raman Research Institute, Bangalore 560 080, India.$$

关键词: ISM: clouds;    kinematics and dynamics;    radio lines: ISM.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

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.

【 授权许可】

Unknown