English
Related papers

Related papers: First CH$_{3}$D detection in Class 0/I proto-brown…

200 papers

In previous warm-up chemical models of the low-mass star-forming region L1527, we investigated the evolution of carbon-chain unsaturated hydrocarbon species when the envelope temperature is slightly elevated to $T\approx 30$ K. These models…

Solar and Stellar Astrophysics · Physics 2015-06-03 George E. Hassel , Nanase Harada , Eric Herbst

We report the first detection of the isotopologues 13CCC and C13CC. We used the heterodyne receivers GREAT and upGREAT on board SOFIA to search for the ro-vibrational transitions Q(2) and Q(4) of 13CCC and C13CC at 1.9 THz along the line of…

We present infrared spectra of brown dwarfs with spectral types from mid-L to T. The 0.9-2.5 $\mu$m spectra of three dwarfs found by the Sloan Digital Sky Survey contain absorption bands of both methane and carbon monoxide and bridge the…

Astrophysics · Physics 2007-05-23 T. R. Geballe , K. S. Noll , S. K. Leggett , G. R. Knapp , X. Fan , D Golimowski

The initial stage of star formation is a complex area study because of its high density and low temperature. Under such conditions, many molecules become depleted from the gas phase by freezing out onto dust grains. However, the deuterated…

The methylidyne cation (CH$^+$) and the methyl cation (CH$_3^+$) are building blocks of organic molecules, yet their coupled formation and excitation mechanisms remain mainly unprobed. The James Webb Space Telescope (JWST), with its high…

We report on a search for Interstellar CH2D+. Four transitions occur in easily accessible portions of the spectrum; we report on emission at the frequencies of these transitions toward high column density star-forming regions. While the…

Astrophysics · Physics 2019-02-12 Alwyn Wootten , Barry E. Turner

We report the detection of the 1_{10}-1_{11} ground state transition of ortho-H_2D^+ at 372.421 GHz in emission from the young stellar object NGC 1333 IRAS 4A. Detailed excitation models with a power-law temperature and density structure…

Astrophysics · Physics 2009-10-31 Ronald Stark , Floris F. S. van der Tak , Ewine F. van Dishoeck

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…

Astrophysics of Galaxies · Physics 2022-11-02 Arijit Manna , Sabyasachi Pal

The low carbon content of Earth and primitive meteorites compared to the Sun and interstellar grains suggests that carbon-rich grains were destroyed in the inner few astronomical units of the young solar system. A promising mechanism to…

Astrophysics of Galaxies · Physics 2024-05-24 Merel L. R. van 't Hoff , Edwin A. Bergin , Penelope Riley , Sanil Mittal , Jes K. Jørgensen , John J. Tobin

Deuterium fractionation in the closest vicinity of a protostar is important in understanding its potential heritage to a planetary system. Here, we have detected the spectral line emission of CH3OH and its three deuterated species, CH2DOH,…

We have conducted a spectral line survey in the 332 - 364 GHz region with the ASTE 10 m telescope toward R CrA IRS7B, a low-mass protostar in the Class 0 or Class 0/I transitional stage. We have also performed some supplementary…

It is currently assumed that infrared dark clouds (IRDCs) represent the earliest evolutionary stages of high-mass stars ($>$ 8 M$_{\odot}$). Submillimeter and millimeter-wave studies performed over the past 15 years show that IRDCs possess…

Solar and Stellar Astrophysics · Physics 2015-06-17 T. Vasyunina , A. I. Vasyunin , E. Herbst , H. Linz , M. Voronkov , T. Britton , I. Zinchenko , F. Schuller

We have measured the deuterium fractionation (through the column density ratio N(N2D+)/N(N2H+)) and the CO depletion factor (ratio between expected and observed CO abundance) in a sample of 10 high-mass protostellar candidates, in order to…

Astrophysics · Physics 2009-11-11 F. Fontani , P. Caselli , A. Crapsi , R. Cesaroni , S. Molinari , L. Testi , J. Brand

The abundances of interstellar CH+ and SH+ are not well understood as their most likely formation channels are highly endothermic. Using data from Herschel, we study the formation of CH+ and SH+ in a typical high UV-illumination…

Clouds of high infrared extinction are promising sites of massive star/cluster formation. A large number of cloud cores discovered in recent years allows investigation of possible evolutionary sequence among cores in early phases. We have…

Astrophysics of Galaxies · Physics 2015-05-30 Huei-Ru Chen , Sheng-Yuan Liu , Yu-Nung Su , Mei-Yan Wang

Brown Dwarfs (BDs) are crucial objects in our understanding of both star and planet formation. However, there is still an unconcluded debate about which is the dominant formation mechanism of these objects. For this, it is mandatory to…

Astrophysics of Galaxies · Physics 2024-10-22 Aina Palau , Nuria Huelamo , David Barrado , Michael M. Dunham , Chang Won Lee

In this letter a near-infrared integral field study of a proto-brown dwarf candidate is presented. A $\sim$ 0\farcs5 blue-shifted outflow is detected in both H$_{2}$ and [Fe II] lines at V$_{sys}$ = (-35~$\pm$ 2)~km~s$^{-1}$ and V$_{sys}$ =…

Solar and Stellar Astrophysics · Physics 2018-03-28 Emma Whelan , Basmah Riaz , Bastien Rouze

We report the first detection in space of the single deuterated isotopologue of methyldiacetylene, CH2DC4H. A total of 12 rotational transitions, with J = 8-12 and Ka = 0 and 1, were identified for this species in TMC-1 in the 31.0-50.4 GHz…

Astrophysics of Galaxies · Physics 2022-01-12 C. Cabezas , R. Fuentetaja , E. Roueff , M. Agundez , B. Tercero , N. Marcelino , J. R. Pardo , P. de Vicente , J. Cernicharo

We upgraded the chemical network from the UMIST Database for Astrochemistry 2006 to include isotopes such as ^{13}C and ^{18}O. This includes all corresponding isotopologues, their chemical reactions and the properly scaled reaction rate…

Astrophysics of Galaxies · Physics 2017-03-15 M. Röllig , V. Ossenkopf

We report the first detection in interstellar space of the 3-cyano propargyl radical (CH2C3N). This species was observed in the cold dark cloud TMC-1 using the Yebes 40m telescope. A total of seven rotational transitions for both ortho- and…