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

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The study of multiple molecular spectral lines in gas infalling sources can provide the physical and chemical properties of these sources and help us estimate their evolutionary stages. We report line detections within the 3 mm band using…

Astrophysics of Galaxies · Physics 2025-04-09 Yang Yang , Xi Chen , ZhiBo Jiang , Zhiwei Chen , Shuling Yu , Jun Li

We report the detection of the propargyl radical (CH2CCH) in the cold dark cloud TMC-1 in the lambda 3 mm wavelength band. We recently discovered this species in space toward the same source at a wavelength of lambda 8 mm. In those…

Astrophysics of Galaxies · Physics 2022-01-19 M. Agundez , N. Marcelino , C. Cabezas , R. Fuentetaja , B. Tercero , P. de Vicente , J. Cernicharo

We report the detection of Deuterium absorption at redshift 2.525659 towards Q1243+3047. We describe improved methods to estimate the Deuterium to Hydrogen abundance ratio (D/H) in absorption systems, including improved modeling of the…

Astrophysics · Physics 2009-11-07 David Kirkman , David Tytler , Nao Suzuki , John M. O'Meara , Dan Lubin

We have studied the photometric variability of very young brown dwarfs and very low-mass stars (masses well below 0.2 M_sun) in the ChaI star forming region. We have determined photometric periods in the Gunn i and R band for the three…

Astrophysics · Physics 2009-11-07 V. Joergens , M. Fernandez , J. M. Carpenter , R. Neuhäuser

The TOPG\"ot project studies a sample of 86 high-mass star-forming regions in different evolutionary stages from starless cores to ultra compact HII regions. The aim of the survey is to analyze different molecular species in a statistically…

Context. Propyne (CH$_3$CCH) has been detected in a variety of environments, from Galactic star-forming regions to extragalactic sources. Such molecules are excellent tracers of the physical conditions in star-forming regions. Aims. This…

We present a new analysis of an absorption system in the spectrum of Q0014+813, with particular attention to a single cold cloud at redshift $z=2.797957$. Features are identified at this redshift corresponding to SiIII, SiIV, CIV, DI, and…

Astrophysics · Physics 2009-10-28 Martin Rugers , Craig J. Hogan

The inheritance of material across the star and planet formation process is traced by deuterium fractionation. We report here the first detection of doubly deuterated methanol towards pre-stellar cores. We study the deuterium fractionation…

Astrophysics of Galaxies · Physics 2023-01-11 Yuxin Lin , Silvia Spezzano , Paola Caselli

We have studied four complex organic molecules (COMs), methyl formate ($CH_3OCHO$), dimethyl ether ($CH_3OCH_3$), formamide ($NH_2CHO$), and ethyl cyanide ($C_2H_5CN$), towards a large sample of 39 high-mass star-forming regions…

Astrophysics of Galaxies · Physics 2020-09-09 A. Coletta , F. Fontani , V. M. Rivilla , C. Mininni , L. Colzi , Á. Sánchez-Monge , M. T. Beltrán

Using the IRAM 30m telescope, we mapped the methanol emission in the pre-stellar core L1544 and observed singly deuterated methanol (CH$_2$DOH and CH$_3$OD) towards the dust peak of L1544. Non-LTE radiative transfer modelling was performed…

Solar and Stellar Astrophysics · Physics 2014-09-17 Luca Bizzocchi , Paola Caselli , Silvia Spezzano , Elvira Leonardo

Aims. We investigate the dominant formation mechanism of H2CO and CH3OH in the Horsehead PDR and its associated dense core. Methods. We performed deep integrations of several H2CO and CH3OH lines at two positions in the Horsehead, namely…

Astrophysics of Galaxies · Physics 2015-06-17 V. V. Guzman , J. R. Goicoechea , J. Pety , P. Gratier , M. Gerin , E. Roueff , F. Le Petit , J. Le Bourlot , A. Faure

Context: Despite the low elemental deuterium abundance in the Galaxy, enhanced molecular D/H ratios have been found in the environments of low-mass star-forming regions and, in particular, the Class 0 protostar IRAS 16293-2422. Aims: The…

Astrophysics of Galaxies · Physics 2015-06-15 A. Coutens , C. Vastel , S. Cazaux , S. Bottinelli , E. Caux , C. Ceccarelli , K. Demyk , V. Taquet , V. Wakelam

The coldest Y spectral type brown dwarfs are similar in mass and temperature to cool and warm ($\sim$200 -- 400 K) giant exoplanets. We can therefore use their atmospheres as proxies for planetary atmospheres, testing our understanding of…

We present one of the first Shanghai Tian Ma Radio Telescope (TMRT) K Band observations towards a sample of 26 infrared dark clouds (IRDCs). We observed the (1,1), (2,2), (3,3), and (4,4) transitions of NH$_{3}$ together with CCS…

Astrophysics of Galaxies · Physics 2022-03-11 Jinjin Xie , Gary A. Fuller , Di Li , Longfei Chen , Zhiyuan Ren , Jingwen Wu , Yan Duan , Junzhi Wang , Juan Li , Nicolas Peretto , Tie Liu , Zhiqiang Shen

A significant fraction of the molecular gas in star-forming regions is irradiated by stellar UV photons. In these environments, the electron density (n_e) plays a critical role in the gas dynamics, chemistry, and collisional excitation of…

Astrophysics of Galaxies · Physics 2019-05-08 S. Cuadrado , P. Salas , J. R. Goicoechea , J. Cernicharo , A. G. G. M. Tielens , A. Baez-Rubio

Using the Yebes 40m and IRAM 30m radiotelescopes, we detected two series of harmonically related lines in space that can be fitted to a symmetric rotor. The lines have been seen towards the cold dense cores TMC-1, L483, L1527, and L1544.…

We have studied twelve very young (1-5Myr) bona fide and candidate brown dwarfs in the ChaI star forming region in terms of their kinematic properties, the occurrence of multiple systems among them as well as their rotational…

(Abridged) We have observed velocity resolved spectra of four ro-vibrational far-infrared transitions of C3 between the vibrational ground state and the low-energy nu2 bending mode at frequencies between 1654--1897 GHz using HIFI on board…

The astronomical gas-phase detection of simple species and small organic molecules in cold pre-stellar cores, with abundances as high as $\sim$$10^{-8}-10^{-9}$ n$_\text{H}$, contradicts the generally accepted idea that at $10$ K, such…

Astrophysics of Galaxies · Physics 2018-06-19 K-J Chuang , G Fedoseev , D Qasim , S Ioppolo , EF van Dishoeck , H Linnartz

A qualitative analysis of the chiral phase transition in QCD at non--zero baryon density is performed. It is assumed that at zero baryonic density, $\rho=0$, the temperature phase transition is of the second order and quark condesate $\eta=…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. L. Ioffe