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Related papers: Detection of interstellar H_2D^+ emission

200 papers

We present Green Bank Telescope (GBT) observations of the 3(12)-3(13) (29 GHz) and 4(13)-4(14) (48 GHz) transitions of the H2CO molecule toward a sample of 23 well-studied star-forming regions. Analysis of the relative intensities of these…

Astrophysics of Galaxies · Physics 2015-05-30 Patrick I. McCauley , Jeffrey G. Mangum , Alwyn Wootten

We have searched for emission from the 557 GHz ortho-water line in the interstellar medium of six nearby starburst galaxies. We used the Odin satellite to observe the 1_10-1_01 transition of o-H2O in the galaxies NGC253, IC342, M82,…

With the incorporation of high-J molecular lines, we aim to constrain the physical conditions of the dense gas in the central region of the Seyfert 2 galaxy NGC 1068 and to determine signatures of the AGN or the starburst contribution. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. P. Perez-Beaupuits , M. Spaans , F. F. S. van der Tak , S. Aalto , S. Garcia-Burillo , A. Fuente , A. Usero

We present Odin observations of the AGB star W Hya in the ground-state transition of ortho-H2O, 1(10)-1(01), at 557GHz. The line is clearly of circumstellar origin. Radiative transfer modelling of the water lines observed by Odin and ISO…

We aim at characterizing the large-scale distribution of H2O in G327.3-0.6, a massive star-forming region made of individual objects in different evolutionary phases. We investigate variations of H2O abundance as function of evolution. We…

Astrophysics of Galaxies · Physics 2017-06-21 S. Leurini , F. Herpin , F. van der Tak , F. Wyrowski , G. J. Herczeg , E. F. van Dishoeck

We present mid-infrared spectral maps of the NGC 1333 star forming region, obtained with the the Infrared Spectrometer on board the Spitzer Space Telescope. Eight pure H2 rotational lines, from S (0) to S (7), are detected and mapped. The…

Context: The depletion of heavy elements in cold cores of interstellar molecular clouds can lead to a situation where deuterated forms of H_3^+ are the most useful spectroscopic probes of the physical conditions. Aims: The aim is to predict…

Astrophysics of Galaxies · Physics 2015-05-14 O. Sipilä , E. Hugo , J. Harju , O. Asvany , M. Juvela , S. Schlemmer

Context: In cold and dense gas prior to the formation of young stellar objects, heavy molecular species (including CO) are accreted onto dust grains. Under these conditions H$_3^+$ and its deuterated isotopologues become more abundant,…

Astrophysics of Galaxies · Physics 2019-01-16 A. Giannetti , S. Bovino , P. Caselli , S. Leurini , D. R. G. Schleicher , B. Koertgen , K. M. Menten , T. Pillai , F. Wyrowski

It has been suggested that the dark halos of galaxies are constituted by cloudlets of cold (< 10 K) H_2 and dense (> 10^7$ cm^{-3}) molecular gas. Such gas is extremely difficult to detect, because the classical tracers of molecular gas, CO…

Astrophysics · Physics 2009-11-11 Cecilia Ceccarelli , Carsten Dominik

We present observations of the v2=0 and vibrationally excited v2=1 J=9-8 rotational lines of HCN at 797 GHz toward the deeply embedded massive young stellar object GL 2591, which provide the missing link between the extended envelope traced…

The L1544 prestellar core has been observed as part of the ASAI IRAM Large Program at 3 mm. These observations led to the detection of many complex molecules. In this Letter, we report the detection of two lines, at 85.5 GHz (4,0,4-3,0,3)…

Astrophysics of Galaxies · Physics 2016-05-27 Charlotte Vastel , Cecilia Ceccarelli , Bertrand Lefloch , Rafael Bachiller

Velocity profiles of ground state lines of H2D+, HC18O+ and N2H+, observed previously with the CSO and IRAM 30m telescopes, are modeled with a Monte Carlo radiative transfer program to study the temperature, density and velocity structure…

Astrophysics · Physics 2009-11-11 F. F. S. van der Tak , P. Caselli , C. Ceccarelli

We have observed 6 clouds along the line-of-sight toward W49A using the Submillimeter Wave Astronomy Satellite (SWAS) and several ground-based observatories. The ortho-H2O 1-0 and OH (1665 and 1667 MHz) transitions are observed in…

We report the first detection of the v=1--0, R(0) ro-vibrational transition of HF at 2.499385 microns arising from interstellar gas. The line is seen in absorption toward 3 background sources---HD 154368, Elias 29, and AFGL 2136 IRS 1---all…

Astrophysics of Galaxies · Physics 2015-06-12 Nick Indriolo , D. A. Neufeld , A. Seifahrt , M. J. Richter

Recent measurements carried out at comet 67P/C-G with the ${\it Rosetta}$ probe revealed that molecular oxygen, O$_2$, is the fourth most abundant molecule in comets. Models show that O$_2$ is likely of primordial nature, coming from the…

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

It is not well known what drives the chemistry of a protostellar envelope, in particular the role of the stellar mass and the outflows on its chemical enrichment. We study the chemical structure of NGC 1333 IRAS 4A in order to (i)…

Astrophysics of Galaxies · Physics 2017-07-12 E. Koumpia , D. A. Semenov , F. F. S. van der Tak , A. C. A. Boogert , E. Caux

We investigate the physical and chemical processes at work during the formation of a massive protostar based on the observation of water in an outflow from a very young object previously detected in H2 and SiO in the IRAS 17233-3606 region.…

Astrophysics of Galaxies · Physics 2014-05-08 S. Leurini , A. Gusdorf , F. Wyrowski , C. Codella , T. Csengeri , F. van der Tak , H. Beuther , D. R. Flower , C. Comito , P. Schilke

We present the first detection in space of O-protonated carbonyl sulfide (\ch{HOCS+}), in the midst of an ultradeep molecular line survey toward the G+0.693-0.027 molecular cloud. From the observation of all $K$$_a$ = 0 transitions ranging…