Searcharxiv⌕ Search

arXiv subjects

Arijit Manna

Publications and source records attributed to Arijit Manna.

28 records · Page 2Linked to original sources

Detection of monothioformic acid towards the solar-type protostar IRAS 16293-2422

In the interstellar medium (ISM), the complex organic molecules that contain the thiol group ($-$SH) play an important role in the polymerization of amino acids. We look for SH-bearing molecules in the chemically rich solar-type protostar IRAS 16293-2422. After the extensive spectral analysis using the local thermodynamic equilibrium (LTE) model, we have detected the rotational emission lines of trans-isomer monothioformic acid (t-HC(O)SH) towards the IRAS 16293 B using the Atacama Large Millimeter/Submillimeter Array (ALMA). We did not observe any evidence of cis-isomer monothioformic acid (c-HC(O)SH) towards the IRAS 16293 B. The column density of t-HC(O)SH towards the IRAS 16293 B was (1.02$\pm$0.6)$\times$10$^{15}$ cm$^{-2}$ with an excitation temperature of 125$\pm$15 K. The fractional abundance of t-HC(O)SH with respect to H$_{2}$ towards the IRAS 16293 B is 8.50$\times$10$^{-11}$. The column density ratio of t-HC(O)SH/CH$_{3}$SH towards the IRAS 16293 B is 0.185. We compare our estimated abundance of t-HC(O)SH towards the IRAS 16293 B with the abundance of t-HC(O)SH towards the galactic center quiescent cloud G+0.693-0.027 and hot molecular core G31.41+0.31. After the comparison, we found that the abundance of t-HC(O)SH towards the IRAS 16293 B is several times of magnitude lower than G+0.693-0.027 and G31.41+0.31. We also discuss the possible formation mechanism of t-HC(O)SH in the ISM.

astro-ph.GA↗

First detection of methyl formate in the hot molecular core IRAS 18566+0408

The studies of the complex molecular emission lines in millimeter and submillimeter wavelengths towards the hot molecular cores demonstrate valuable details about the chemical complexity in the interstellar medium (ISM). We presented the first detection of the rotational emission lines of the complex organic molecule methyl formate (CH$_{3}$OCHO) towards the hot molecular core region IRAS 18566+0408 using the high-resolution Atacama Large Millimeter/Submillimeter Array (ALMA) band 3 observation. The estimated column density of CH$_{3}$OCHO using the rotational diagram analysis was (4.1$\pm$0.1)$\times$10$^{15}$ cm$^{-2}$ with rotational temperature 102.8$\pm$1.2 K. The estimated fractional abundance of CH$_{3}$OCHO towards the IRAS 18566+0408 relative to hydrogen (H$_{2}$) was 3.90$\times$10$^{-9}$. We noted that the estimated fractional abundance of CH$_{3}$OCHO is fairly consistent with the simulation value predicted by the three-phase warm-up model from Garrod (2013). We also discussed the possible formation mechanism of CH$_{3}$OCHO towards the hot molecular cores.

astro-ph.GA↗

Detection of interstellar cyanamide (NH$_{2}$CN) towards the hot molecular core G10.47+0.03

In the interstellar medium, the amide-type molecules play an important role in the formation of the prebiotic molecules in the hot molecular cores or high-mass star formation regions. The complex amide-related molecule cyanamide (NH$_{2}$CN) is known as one of the rare interstellar molecule which has played a major role in the formation of urea (NH$_{2}$CONH$_{2}$). In this article, we presented the detection of the emission lines of cyanamide (NH$_{2}$CN) towards the hot molecular core G10.47+0.03 between the frequency range 158.49$-$160.11 GHz using the Atacama Large Millimeter/submillimeter Array (ALMA) interferometric radio telescope. The estimated column density of the emission lines of NH$_{2}$CN using the rotational diagram model was $N$(NH$_{2}$CN) = (6.60$\pm$0.1)$\times$10$^{15}$ cm$^{-2}$ with rotational temperature ($T_{rot}$) = 201.2$\pm$3.3 K. The fractional abundance of NH$_{2}$CN with respect to H$_{2}$ towards G10.47+0.03 was $f$(NH$_{2}$CN) = 5.076$\times$10$^{-8}$. Additionally, we estimated the NH$_{2}$CN/NH$_{2}$CHO abundance ratio towards the G10.47+0.03 was 0.170, which was nearly similar with NH$_{2}$CN/NH$_{2}$CHO abundance ratio towards IRAS 16293$-$2422 B and Sgr B2 (M). We found that the observed abundance of NH$_{2}$CN with respect to H$_{2}$ towards G10.47+0.03 fairly agrees with the theoretical value predicted by Garrod (2013). We also discussed the possible formation and destruction pathways of NH$_{2}$CN.

astro-ph.GA↗

Identification of interstellar amino acetonitrile in the hot molecular core G10.47+0.03: Possible glycine survey candidate for the future

Amino acids are the essential keys that contribute to the study of the formation of life. The simplest amino acid, glycine (NH$_{2}$CH$_{2}$COOH), has been searched for a long time in the interstellar medium, but all surveys of glycine have failed. Since the detection of glycine in the interstellar medium was extremely difficult, we aimed to search for the precursor of glycine. After detailed searches of the individual prebiotic molecular species, we successfully identified the emission lines of possible glycine precursor molecule amino acetonitrile (NH$_{2}$CH$_{2}$CN) towards the hot molecular core G10.47+0.03 using the Atacama Large Millimeter/Submillimeter Array. We estimated the statistical column density of amino acetonitrile was (9.10$\pm$0.7)$\times$10$^{15}$ cm$^{-2}$ with rotational temperature ($T_{rot}$) 122$\pm$8.8 K. The estimated fractional abundance of amino acetonitrile was 7.01$\times$10$^{-8}$. We found that the estimated fractional abundance of NH$_{2}$CH$_{2}$CN fairly agrees with the theoretical value predicted by the three-phase warm-up model from Garrod (2013).

astro-ph.GA↗

Detection of continuum emission and atomic hydrogen (HI) from comet C/2020 F3 NEOWISE using GMRT

Comets are the most primordial objects in our solar system. Comets are icy bodies that release gas and dust when they move close to the Sun. The C/2020 F3 (NEOWISE) was a nearly isotropic comet that was moving in a near-parabolic orbit. The comet C/2020 F3 (NEOWISE) was the brightest comet in the northern hemisphere after comet Hale-Bopp in 1997 and comet McNaught in 2006. In this article, we reported the first interferometric high-resolution detection of the comet C/2020 F3 (NEOWISE) using the Giant Metrewave Radio Telescope (GMRT). We detected the radio continuum emission from comet C/2020 F3 (NEOWISE) with flux density level 2.84($\pm$0.56)$-$3.89($\pm$0.57) mJy in the frequency range 1050$-$1450 MHz. We also detected the absorption line of atomic HI with Signal to Noise Ratio (SNR) $\sim$5.7. The statistical column density of the detected HI absorption line was $N_{HI} = (3.46\pm0.60)\times(T_{s}/100)\times10^{21}$ cm$^{-2}$ where we assumed spin temperature $T_{s}$ = 100 K and filling factor $f$ = 1. The significant detection of continuum emission from the comet C/2020 F3 (NEOWISE) in $\sim$21 cm wavelength indicated that it arose from the large Icy Grains Halo (IGH) region.

astro-ph.EP↗

ALMA detection of water vapour in the low mass protostar IRAS 16293$-$2422

The low mass protostar IRAS 16293$-$2422 is a well-known young stellar system that is observed in the L1689N molecular cloud in the constellation of Ophiuchus. In the interstellar medium and solar system bodies, water is a necessary species for the formation of life. We present the spectroscopic detection of the rotational emission line of water (H$_{2}$O) vapour from the low mass protostar IRAS 16293$-$2422 using the Atacama Large Millimeter/submillimeter Array (ALMA) band 5 observation. The emission line of H$_{2}$O is detected at frequency $ν$ = 183.310 GHz with transition J=3$_{1,3}$$-$2$_{2,2}$. The statistical column density of the emission line of water vapour is $N$(H$_{2}$O) = 4.2$\times$10$^{16}$ cm$^{-2}$ with excitation temperature ($T_{ex}$) = 124$\pm$10 K. The fractional abundance of H$_{2}$O with respect to H$_{2}$ is 1.44$\times$10$^{-7}$ where $N$(H$_{2}$) = 2.9$\times$10$^{23}$ cm$^{-2}$.

astro-ph.GA↗

ALMA detection of sulfur dioxide and carbon monoxide in the atmosphere of Neptune

The space and ground-based observations have shown a lot of activities and instabilities in the atmosphere of the giant ice planet Neptune. Using the archival data of high resolution Atacama Large Millimeter/Submillimeter Array (ALMA) with band 7 observation, we present the spectroscopic detection of the rotational emission line of sulfur dioxide (SO$_{2}$) at frequency $ν$ = 343.476 GHz with transition J=57$_{15,43}$$-$58$_{14,44}$. We also re-detect the emission line of carbon monoxide (CO) at frequency $ν$ = 345.795 GHz with transition J=3$-$2. The molecular lines of SO$_{2}$ and CO in the atmosphere of Nepure are detected with the $\geq$4$σ$ statistical significance. The statistical column density of SO$_{2}$ is N(SO$_{2}$) = 2.61$\times$10$^{15}$ cm$^{-2}$ with rotational temperature $T_{SO_{2}}$ = 50 K and the statistical column density CO is N(CO) = 1.86$\times$10$^{19}$ cm$^{-2}$ with $T_{CO}$ = 29 K. The typical mixing ratio in the atmosphere of Neptune for SO$_{2}$ is 1.24$\times$10$^{-10}$ and CO is 0.88$\times$10$^{-6}$. The SO$_{2}$ and CO gas in the atmosphere of Neptune may create due to Shoemaker-Levy 9 impacts in Jovian planets since 1994.

astro-ph.EP↗

ALMA detection of acetone, disulfur monoxide, and carbon monoxide in the Jupiter volcanic moon Io

The extremely thin atmosphere of Jupiter's volcanic moon Io primarily consists of sulfur (S), sodium (Na), and oxygen (O) molecules that are controlled by the combination of the sublimation and volcanic outgasses. We present the first spectroscopic detection of the two rotational emission lines of acetone (CH$_{3}$COCH$_{3}$) and a single emission line of disulfur monoxide (S$_{2}$O), and carbon monoxide (CO) at frequency $ν$ = 346.539, 346.667, 346.543, and 345.795 GHz respectively using the archival data of high-resolution Atacama Large Millimeter/Submillimeter Array (ALMA) interferometer with band 7 observation. All molecular species are detected with $\ge$5$σ$ statistical significance. Jupiter's moon Io is the most volcanically active body in the solar system with a very thin and spatially variable atmosphere. The volcanic gas CH$_{3}$COCH$_{3}$, S$_{2}$O, and CO are mainly coming from volcanic plumes. The statistical column density of CH$_{3}$COCH$_{3}$ line is N(CH$_{3}$COCH$_{3}$) = 3.18$\times$10$^{15}$ cm$^{-2}$ but for the cases of S$_{2}$O and CO, the column densities are N(S$_{2}$O) = 2.63$\times$10$^{16}$ cm$^{-2}$ and N(CO) = 5.27$\times$10$^{15}$ cm$^{-2}$ respectively. The carbon monoxide gas is mainly formed by the photolysis of the volcanic gas acetone.

astro-ph.EP↗

Detection of simplest amino acid glycine in the atmosphere of Venus

Amino acids are considered to be prime ingredients in chemistry, leading to life. Glycine is the simplest amino acid and most commonly found in animal proteins. It is a glucogenic and non-essential amino acid that is produced naturally by living bodies and plays a key role in the creation of several other important bio-compounds and proteins. We report the first spectroscopic detection of the rotational absorption lines of the simplest amino acid glycine (NH$_{2}$CH$_{2}$COOH) with confirmer I and II in the atmosphere of Venus using the archival data from the Atacama Large Millimeter/Submillimeter Array (ALMA). We detect the eleven rotational absorption lines of NH$_{2}$CH$_{2}$COOH between the frequency range of $ν$ = 245$-$262 GHz with $\geq$3$σ$ statistical significance. We calculate the total column density of glycine in the atmosphere of Venus is $N$(NH$_{2}$CH$_{2}$COOH) $\sim$ 5$\times$10$^{14}$ cm$^{-2}$. Using the column density information of glycine, we calculate the abundance of glycine is $\sim$ 1.6$\times$10$^{-9}$ in the atmosphere of Venus. The detection of glycine in the atmosphere of Venus might be one of the keys to an understanding of the formation mechanisms of prebiotic molecules in the atmosphere of Venus. The detection of glycine indicates that the upper atmosphere of Venus may be going through nearly the same biological method as Earth billions of years ago.

astro-ph.EP↗

ALMA spectroscopic detection of water vapour in the atmosphere of the giant gas planet Jupiter

In the Jovian atmosphere, the trace species are detected for the first time after the collision of comet Shoemaker-Levy 9 near 44$^\circ$S in July 1994. Most of these trace species are detected with spectroscopic millimeter/submillimeter observation. In the atmosphere of Jupiter, trace gases play an important role in atmospheric chemistry with heterogeneous and homogeneous chemical reactions, interaction with radiation, and phase transition. Here we present the first spectroscopic detection of the rotational emission line of water (H$_{2}$O) in the atmosphere of Jupiter at frequency $ν$ = 183.310 GHz with molecular transition J = 3$_{1,3}$$-$2$_{2,2}$ using Atacama Large Millimeter/Submillimeter Array (ALMA). The statistical column density of water emission line is N(H$_{2}$O)$\sim$4$\times$10$^{15}$ cm$^{-2}$. The rotational emission line of H$_{2}$O is found in the stratosphere of Jupiter with $\geq$3$σ$ statistical significance. The column density of H$_{2}$O corresponds to the fractional abundance relative to H$_{2}$ is f(H$_{2}$O)$\sim$ 4$\times$10$^{-9}$.

astro-ph.EP↗