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تسجيل مستخدم جديدDetection of the atomic hydrogen (HI) absorption line and continuum emission from comet C/2020 F3 (NEOWISE) using GMRT
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Comets are the most primordial objects in our solar system which are made of icy bodies. Comets used to release gas and dust when it moves close to the Sun. The C/2020 F3 (NEOWISE) is a large periodic comet that is moving in a near-parabolic orbit. The C/2020 F3 (NEOWISE) is the brightest comet in the northern hemisphere after comet Hale-Bopp in 1997. Here we present the first interferometric high-resolution detection of the comet C/2020 F3 (NEOWISE) using the Giant Metrewave Radio Telescope (GMRT). The observational frequency range is 1050$-$1450 MHz. We detect the radio continuum emission from this comet with flux density level 2.8$-$3.4 mJy between the frequency range 1050--1450 MHz. We also detect atomic HI absorption line at $ u$ = 1420 MHz ($sim$5$sigma$ significance) with column density $N(textrm {HI}) = (1.8 pm 0.09)times 10^{22}$ cm$^{-2}$. The continuum emission from the comet in meter wavelength arises from the large Icy Grains Halo (IGH) region. Significant detection of C/2020 F3 in $sim$21 cm indicates the presence of large size of particles in the coma region of the comet.
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