activity
20082025
most citedSpitzer Space Telescope spectra of post-AGB stars in the Large Magellanic Cloud ---polycyclic aromatic hydrocarbons at low metallicities

91 citations · 1.1k across the 43 of their papers we have counts for

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Showing astro-ph.GAShow all

35 papers · 1 filter

astro-ph.GA2025

Searching for missing interstellar oxygen in the far-infrared

Takashi Onaka, Itsuki Sakon, Takashi Shimonishi +1

Study of interstellar elemental depletion poses an important problem in the interstellar matter that at least a quarter of the total oxygen ( ppm relative to hydrogen) is…

astro-ph.GA2025

Binding energy distributions of alcohols, thiols, and their precursors on interstellar water ice surfaces

Arghyadeb Roy, Ankan Das, Milan Sil +4

Binding energy (BE) is a critical parameter in astrochemical modeling, governing the retention of species on interstellar dust grains and their subsequent chemical evolution. Howev…

astro-ph.GA2025

The detection of spatially resolved protosteller outflows and episodic jets in the outer Galaxy

Toki Ikeda, Takashi Shimonishi, Natsuko Izumi +5

We present the first detection of spatially resolved protostellar outflows and jets in the outer Galaxy. We observed five star-forming regions in the outer Galaxy (Sh 2--283, NOMF0…

astro-ph.GA2025

ALMA Observations of Peculiar Embedded Icy Objects

Takashi Shimonishi, Takashi Onaka, Itsuki Sakon

We report the results of molecular line observations with the Atacama Large Millimeter/submillimeter Array (ALMA) towards two peculiar icy objects, which were discovered serendipit…

astro-ph.GA2025★ 3 cited

ALMA 0.1 pc View of Molecular Clouds Associated with High-Mass Protostellar Systems in the Small Magellanic Cloud: Are Low-Metallicity Clouds Filamentary or Not?

Kazuki Tokuda, Yuri Kunitoshi, Sarolta Zahorecz +13

Filamentary molecular clouds are an essential intermediate stage in the star formation process. To test whether these structures are universal throughout cosmic star formation hist…

astro-ph.GA2024★ 9 cited

Assessing realistic binding energies of some essential interstellar radicals with amorphous solid water. A fully quantum chemical approach

Milan Sil, Arghyadeb Roy, Prasanta Gorai +6

In the absence of laboratory data, state-of-the-art quantum chemical approaches can provide estimates of the binding energy (BE) of interstellar species with grains. Without BE val…

astro-ph.GA2024★ 1 cited

Deep Search for Phosphine in a Prestellar Core

Kenji Furuya, Takashi Shimonishi

Understanding in which chemical forms phosphorus exists in star- and planet-forming regions and how phosphorus is delivered to planets are of great interest from the viewpoint of t…

astro-ph.GA2023★ 17 cited

An ALMA Glimpse of Dense Molecular Filaments Associated with High-mass Protostellar Systems in the Large Magellanic Cloud

Kazuki Tokuda, Naoto Harada, Kei E. I. Tanaka +10

Recent millimeter/sub-millimeter facilities have revealed the physical properties of filamentary molecular clouds in relation to high-mass star formation. A uniform survey of the n…

astro-ph.GA2023★ 4 cited

Cosmic-ray-driven enhancement of the C/CO abundance ratio in W51C

Mitsuyoshi Yamagishi, Kenji Furuya, Hidetoshi Sano +5

We examine spatial variations of the C/CO abundance ratio () in the vicinity of the -ray supernova remnant W51C, based on [CI] (-), C…

astro-ph.GA2023★ 19 cited

The Detection of Hot Molecular Cores in the Small Magellanic Cloud

Takashi Shimonishi, Kei E. I. Tanaka, Yichen Zhang +1

We report the first detection of hot molecular cores in the Small Magellanic Cloud, a nearby dwarf galaxy with 0.2 solar metallicity. We observed two high-mass young stellar object…

astro-ph.GA2022★ 13 cited

Near-infrared spectroscopy of a massive young stellar object in the direction toward the Galactic Center: XCN and aromatic C-D features

Takashi Onaka, Itsuki Sakon, Takashi Shimonishi

We report near-infrared (2.5--5 micron) long-slit (~ 30 arcsec) spectroscopy of a young stellar object in the direction toward the Galactic center with the Infrared Camera on board…

astro-ph.GA2022★ 13 cited

The First Detection of a Protostellar CO Outflow in the Small Magellanic Cloud with ALMA

Kazuki Tokuda, Sarolta Zahorecz, Yuri Kunitoshi +12

Protostellar outflows are one of the most outstanding features of star formation. Observational studies over the last several decades have successfully demonstrated that outflows a…

astro-ph.GA2021★ 25 cited

Quantifying the chemical desorption of HS and PH from amorphous water ice surfaces

Kenji Furuya, Yasuhiro Oba, Takashi Shimonishi

Nonthermal desorption of molecules from icy grain surfaces is required to explain molecular line observations in the cold gas of star-forming regions. Chemical desorption is one of…

astro-ph.GA2021★ 45 cited

The detection of a hot molecular core in the extreme outer Galaxy

Takashi Shimonishi, Natsuko Izumi, Kenji Furuya +1

Interstellar chemistry in low metallicity environments is crucial to understand chemical processes in the past metal-poor universe. Recent studies of interstellar molecules in near…

astro-ph.GA2021★ 36 cited

Transmission Electron Microscopy Study of the Morphology of Ices Composed of H2O, CO2, and CO on Refractory Grains

Akira Kouchi, Masashi Tsuge, Tetsuya Hama +15

It has been implicitly assumed that ices on grains in molecular clouds and proto planetary disks are formed by homogeneous layers regardless of their composition or crystallinity.…

astro-ph.GA2021★ 23 cited

Is there any linkage between interstellar aldehyde and alcohol?

Suman Kumar Mondal, Prasanta Gorai, Milan Sil +8

It is speculated that there might be some linkage between interstellar aldehydes and their corresponding alcohols. Here, an observational study and astrochemical modeling are coupl…

astro-ph.GA2021★ 30 cited

Chemical complexity of phosphorous bearing species in various regions of the Interstellar medium

Milan Sil, Satyam Srivastav, Bratati Bhat +10

Phosphorus related species are not known to be as omnipresent in space as hydrogen, carbon, nitrogen, oxygen, and sulfur-bearing species. Astronomers spotted very few P-bearing mol…

astro-ph.GA2021★ 5 cited

Discovery of two infrared objects with strong ice absorption in the AKARI slit-less spectroscopic survey of the Galactic Plane

Takashi Onaka, Tomoyuki Kimura, Itsuki Sakon +1

We discover two infrared objects that show deep absorption features of H2O, CO2, and CO ices in the AKARI/Infrared Camera (IRC) slit-less spectroscopic survey of the Galactic plane…

astro-ph.GA2020★ 24 cited

Identification of Methyl Isocyanate and Other Complex Organic Molecules in a Hot Molecular Core, G31.41+0.31

Prasanta Gorai, Ankan Das, Takashi Shimonishi +4

G31.41+0.31 is a well known chemically rich hot molecular core (HMC). Using Band 3 observations of Atacama Large Millimeter Array (ALMA), we have analyzed the chemical and physical…

astro-ph.GA2020★ 10 cited

A Systematic Study on the Absorption Features of Interstellar Ices in Presence of Impurities

Prasanta Gorai, Milan Sil, Ankan Das +12

Spectroscopic studies play a key role in the identification and analysis of interstellar ices and their structure. Some molecules have been identified within the interstellar ices…

astro-ph.GA2020★ 30 cited

Chemistry and physics of a low-metallicity hot core in the Large Magellanic Cloud

Takashi Shimonishi, Ankan Das, Nami Sakai +5

We present the results of 0.1-pc-scale observations in 250 GHz and 350GHz towards a newly-discovered hot molecular core in a nearby low-metallicity galaxy, the Large Magellanic Clo…

astro-ph.GA2019★ 22 cited

Complex Organic Molecules in Star-Forming Regions of the Magellanic Clouds

Marta Sewiło, Steven B. Charnley, Peter Schilke +14

The Large and Small Magellanic Clouds (LMC and SMC), gas-rich dwarf companions of the Milky Way, are the nearest laboratories for detailed studies on the formation and survival of…

astro-ph.GA2018★ 22 cited

Molecular-Cloud-Scale Chemical Composition III: Constraints of Average Physical Properties through Chemical Models

Nanase Harada, Yuri Nishimura, Yoshimasa Watanabe +4

It is important to understand the origin of molecular line intensities and chemical composition in the molecular-cloud scale in the Galactic sources because it serves as a benchmar…

astro-ph.GA2018★ 15 cited

A multiline study of a high-mass young stellar object in the Small Magellanic Cloud with ALMA: The detection of methanol gas at 0.2 solar metallicity

Takashi Shimonishi, Yoshimasa Watanabe, Yuri Nishimura +5

We report the results of subparsec-scale submillimeter observations towards an embedded high-mass young stellar object in the Small Magellanic Cloud (SMC) with ALMA. Complementary…