Query : 2016A&A...594A.117P

2016A&A...594A.117P - Astronomy and Astrophysics, volume 594A, 117-117 (2016/10-1)

The CO-H2 van der Waals complex and complex organic molecules in cold molecular clouds: A TMC-1C survey.


Abstract (from CDS):

Context. Almost 200 different species have been detected in the interstellar medium (ISM) during the last decades, revealing not only simple species but complex molecules with more than six atoms. Other exotic compounds, like the weakly-bound dimer (H2)2, have also been detected in astronomical sources like Jupiter.
Aims. We aim to detect, for the first time, the CO-H2 van der Waals complex in the ISM, which could be a sensitive indicator for low temperatures if detected.
Methods. We used the IRAM 30 m telescope, located in Pico Veleta (Spain), to search for the CO-H2 complex in a cold, dense core in TMC-1C (with a temperature of ∼10K). All the brightest CO-H2 transitions in the 3mm (80-110GHz) band were observed with a spectral resolution of 0.5-0.7km/s, reaching a rms noise level of ∼2mK. The simultaneous observation of a broad frequency band, 16GHz, allowed us to conduct a serendipitous spectral line survey.
Results. We did not detected any lines belonging to the CO-H2 complex. We set up a new, more stringent upper limit for its abundance to be [CO-H2]/[CO]∼5x10–6, while we expect the abundance of the complex to be in the range ∼10–8-10–3. The spectral line survey has allowed us to detect 75 lines associated with 41 different species (including isotopologues). We detect a number of complex organic species, for example methyl cyanide (CH3CN), methanol (CH3OH), propyne (CH3CCH), and ketene (CH2CO), associated with cold gas (excitation temperatures ∼7K), confirming the presence of these complex species not only in warm objects but also in cold regimes.

Abstract Copyright: © ESO, 2016

Journal keyword(s): astrochemistry - molecular processes - methods: observational - techniques: spectroscopic - radio lines: ISM - ISM: molecules

VizieR on-line data: <Available at CDS (J/A+A/594/A117): tmc1clsb.dat tmc1cusb.dat>

Simbad objects: 4

goto Full paper

goto View the references in ADS

Number of rows : 4
N Identifier Otype ICRS (J2000)
ICRS (J2000)
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
1 NAME Taurus Complex SFR 04 41.0 +25 52           ~ 4250 0
2 Barnard 220 DNe 04 41 38.8 +26 00 42           ~ 135 0
3 LDN 1544 DNe 05 04 16.6 +25 10 48           ~ 832 0
4 LDN 1689B DNe 16 34 42.1 -24 36 11           ~ 163 0

To bookmark this query, right click on this link: simbad:objects in 2016A&A...594A.117P and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact