| Abstract: | Compact starburst galaxies such as Blue Compact Dwarf galaxies (BCDs), Green Peas and Blueberry galaxies at nearby redshifts act as local laboratories to understand star formation in the early primordial Universe. Studying atomic HI gas content and gas depletion time scales can provide insights into the evolutionary processes of these galaxies. In this talk, I will present our recent work on, actively star-forming, blue compact dwarf galaxies (BCDs) and blueberry galaxies from 21 cm observations with the Arecibo Observatory, Giant Metrewave Radio Telescope (GMRT) and Five hundred metre Aperture Spherical radio Telescope (FAST). Of the 11 BCDs observed with the Arecibo telescope, HI emission was detected in six sources. For comparison, we used the HI data of additional dwarf irregulars (dIs) and BCDs in the literature. BCDs observed with the Arecibo have HI mass-stellar mass relation similar to that from earlier observations which implies that HI gas dominates the baryons at lower stellar masses. BCDs observed with the Arecibo Observatory have significantly lower median HI depletion timescales of ∼ 0.3 Gyr than depletion scales of other dIs/BCDs in literature. I will also present the results from follow-up deep HI observations of two BCDs with GMRT where we find that star formation takes place in high HI gas density regions. After that, I will present the results of our recent HI study of 28 blueberry galaxies with FAST. We have detection towards only two sources and a low median depletion timescale upper limit of ~0.5 Gyr from non-detections. We find blueberry galaxies tend to have a lower gas fraction (HI-to-stellar mass ratio) than expected from gas fraction-stellar mass relation for main-sequence galaxies. I will conclude with the prospects for HI studies with the Square Kilometer Array (SKA) pathfinders such as GMRT, FAST, MeerKAT and SKA in future.
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