Related papers: New submillimetre HCN lasers in carbon-rich evolve…
We report the detection of a strong submillimeter wavelength HCN laser line at a frequency near 805 GHz toward the carbon star IRC+10216. This line, the J=9-8 rotational transition within the (04(0)0) vibrationally excited state, is one of…
Context. HCN is the most abundant molecule after H$_{2}$ and CO in the circumstellar envelopes (CSEs) of carbon-rich asymptotic giant branch (AGB) stars. Its rotational lines within vibrationally excited states are exceptional tracers of…
High spectral resolution observations toward the low mass-loss rate C-rich, J-type AGB star Y CVn have been carried out at 7.5, 13.1 and 14.0 um with SOFIA/EXES and IRTF/TEXES. Around 130 HCN and H13CN lines of bands v2, 2v2, 2v2-v2,…
Context. HCN is a major constituent of the circumstellar envelopes of carbon-rich evolved stars, and rotational lines from within its vibrationally excited states probe parts of these regions closest to the stellar surface. A number of such…
We studied the abundance of HCN, H13CN, and HN13C in a sample of prestellar cores, in order to search for species associated with high density gas. We used the IRAM 30m radiotelescope to observe along the major and the minor axes of L1498,…
We present here the sensitive HCN(1-0) observations made with the VLA of two submillimeter galaxies and two QSOs at high-redshift. HCN emission is the signature of dense molecular gas found in GMC cores, the actual sites of massive star…
We have observed HNC 1-0, CN 1-0 and 2-1 line emission in a sample of 13 IR luminous (LIRGs, L_IR > 10E11 Lo) starburst and Seyfert galaxies. HNC 1-0 is detected in 9, CN 1-0 is detected in 10 and CN 2-1 in 7 of the galaxies. We also report…
Molecular line emission from high-redshift galaxies holds great promise for the study of galaxy formation and evolution. The weak signals can only be detected with the largest mm-wave telescopes, such as the IRAM interferometer. We report…
A multi-transition survey of HCN (sub-) millimeter line emission from a large sample of AGB stars of different chemical type is presented. The data are analysed and circumstellar HCN abundances are estimated. The sample stars span a large…
Understanding the nuclear growth and feedback processes in galaxies requires investigating their often obscured central regions. One way to do this is to use (sub)millimeter line emission from vibrationally excited HCN (HCN-vib). It has…
Compiling data from literature and the ALMA archive, we show enhanced HCN(4-3)/HCO$^+$(4-3) and/or HCN(4-3)/CS(7-6) integrated intensity ratios in circumnuclear molecular gas around active galactic nuclei (AGNs) compared to those in…
We investigate the molecular gas properties of a sample of 23 galaxies in order to find and test chemical signatures of galaxy evolution and to compare them to IR evolutionary tracers. Observation at 3 mm wavelengths were obtained with the…
Aims. Our aim is to confirm the interstellar detection of cyanic acid, HOCN, in the Galactic center clouds. It has previously been tentatively detected only in Sgr B2(OH). Methods. We used a complete line survey of the hot cores Sgr B2(N)…
We present 5 deg^2 (~250 pc^2) HCN, HNC, HCO+, and CO J=1-0 maps of the Orion B GMC, complemented with existing wide-field [CI] 492 GHz maps, as well as new pointed observations of rotationally excited HCN, HNC, H13CN, and HN13C lines. We…
We present a search for HCN emission from four high redshift far infrared (IR) luminous galaxies. Current data and models suggest that these high $z$ IR luminous galaxies represent a major starburst phase in the formation of spheroidal…
We surveyed 81 dense molecular cores associated with regions of massive star formation and Sgr A in the 5_{05}-4_{04} and 10_{010}-9_{09} lines of HNCO. Line emission was detected towards 57 objects. Selected subsamples were also observed…
We report deep K-band (18-27GHz) observations with the 100-m Green Bank Telescope of HCN(1-0) line emission towards the two submillimeter-selected galaxies (SMGs) SMMJ02399-0136 (z=2.81) and SMMJ16359+6612 (z=2.52). For both sources we have…
We have identified a new vibrational HCN maser at 89.087 GHz in the asymptotic giant branch (AGB) star IRAS 15082-4808, a maser which is thought to trace the innermost region of an AGB envelope. The observations of this maser at three…
A millimeter molecular line survey of three carbon-rich AGB stars and two oxygen-rich planetary nebulae has been carried out over the frequency range 80.5-115.5 GHz. Sixty eight different transitions were detected in the data from 27…
We present the detection of molecular absorption lines in the optical spectrum of the post-AGB star HD56126. The C2 Phillips A^{1}\Pi_{u}-X^{1}\Sigma^{+}_{g} (1,0), (2,0), and (3,0); Swan d^{3}\Pi_{g}-a^{3}\Pi_{u} (0,0) and (1,0); and CN…