2010A&A...521L..14Q

Query : 2010A&A...521L..14Q

2010A&A...521L..14Q - Astronomy and Astrophysics, volume 521, L14-14 (2010/10-1)

Herschel observations of EXtra-Ordinary Sources (HEXOS): detecting spiral arm clouds by CH absorption lines.

QIN S.-L., SCHILKE P., COMITO C., MOELLER T., ROLFFS R., MUELLER H.S.P., BELLOCHE A., MENTEN K.M., LIS D.C., PHILLIPS T.G., BERGIN E.A., BELL T.A., CROCKETT N.R., BLAKE G.A., CABRIT S., CAUX E., CECCARELLI C., CERNICHARO J., DANIEL F., DUBERNET M.-L., EMPRECHTINGER M., ENCRENAZ P., FALGARONE E., GERIN M., GIESEN T.F., GOICOECHEA J.R., GOLDSMITH P.F., GUPTA H., HERBST E., JOBLIN C., JOHNSTONE D., LANGER W.D., LORD S.D., MARET S., MARTIN P.G., MELNICK G.J., MORRIS P., MURPHY J.A., NEUFELD D.A., OSSENKOPF V., PAGANI L., PEARSON J.C., PERAULT M., PLUME R., SALEZ M., SCHLEMMER S., STUTZKI J., TRAPPE N., VAN DER TAK F.F.S., VASTEL C., WANG S., YORKE H.W., YU S., ZMUIDZINAS J., BOOGERT A., GUESTEN R., HARTOGH P., HONINGH N., KARPOV A., KOOI J., KRIEG J.-M., SCHIEDER R., DIEZ-GONZALEZ M.C., BACHILLER R., MARTIN-PINTADO J., BAECHTOLD W., OLBERG M., NORDH L.H., GILL J.L. and CHATTOPADHYAY G.

Abstract (from CDS):

We have observed CH absorption lines (J=3/2, N=1 using the Herschel/HIFI instrument. With the high spectral resolution and wide velocity coverage provided by HIFI, 31 CH absorption features with different radial velocities and line widths are detected and identified. The narrower line width and lower column density clouds show ``spiral arm'' cloud characteristics, while the absorption component with the broadest line width and highest column density corresponds to the gas from the Sgr B2 envelope. The observations show that each ``spiral arm'' harbors multiple velocity components, indicating that the clouds are not uniform and that they have internal structure. This line-of-sight through almost the entire Galaxy offers unique possibilities to study the basic chemistry of simple molecules in diffuse clouds, as a variety of different cloud classes are sampled simultaneously. We find that the linear relationship between CH and H₂ column densities found at lower A_V by UV observations does not continue into the range of higher visual extinction. There, the curve flattens, which probably means that CH is depleted in the denser cores of these clouds.

Abstract Copyright: ∼

Journal keyword(s): ISM: abundances - ISM: molecules

Simbad objects: 11

Full paper

View the references in ADS

Number of rows : 11

N	Identifier	Otype	ICRS (J2000) RA	ICRS (J2000) DEC	Mag V	Sp type	#ref 1850 - 2023	#notes
1	NAME Nor Arm	PoG	16 00	-50.0		~	411	0
2	NGC 6334	HII	17 20 53	-36 07.9		~	674	0
3	NAME Galactic Center	reg	17 45 39.60213	-29 00 22.0000		~	13889	0
4	NAME Sgr B2 (North)	Rad	17 47 20.2	-28 22 21		~	646	1
5	NAME Sgr B2	MoC	17 47 20.4	-28 23 07		~	2198	1
6	NAME Sgr B2 Main	Rad	17 47 20.5	-28 23 06		~	390	1
7	NAME Sgr Arm	PoG	19 00	-30.0		~	624	1
8	W 49	SFR	19 10 20	+09 07.7		~	564	1
9	W 51	SNR	19 23 50	+14 06.0		~	1258	1
10	NAME Cas A	SNR	23 23 24.000	+58 48 54.00	14.30	~	2724	1
11	NAME Scutum Spiral Arm	PoG	~	~		~	340	0

To bookmark this query, right click on this link: simbad:objects in 2010A&A...521L..14Q and select 'bookmark this link' or equivalent in the popup menu