THE EFFECT OF VARYING COSMIC-RAY IONIZATION RATES ON DARK CLOUD CHEMISTRY

被引：40

作者：

FARQUHAR, PRA

MILLAR, TJ

HERBST, E

机构：

[1] Department of Mathematics, UMIST, PO Box 88, Manchester

[2] Departments of Physics and Astronomy, Ohio State University, 174 W. 18th Avenue, Columbus, 43210, OH

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 1994年 / 269卷 / 03期

基金：

美国国家科学基金会;

关键词：

MOLECULAR PROCESSES; ISM; CLOUDS; COSMIC RAYS; MOLECULES; GALAXIES; ABUNDANCES;

D O I：

10.1093/mnras/269.3.641

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We investigate the effects of varying the cosmic ray ionization rate in chemical models of dense interstellar clouds. In the absence of such ionization, a scenario which may be applicable to dark cloud cores, we find that chemi-ionization is able to drive a limited ion-neutral chemistry. Models of clouds in starburst galaxies, which may have enhanced cosmic ray fluxes, are also investigated and enable an upper limit to be derived for the cosmic ray ionization rate in M82. The derived value, which is about 700 times the typical value for Galactic molecular clouds, is in good agreement with that necessary to explain the recent observations of C I in this galaxy.

引用

页码：641 / 648

页数：8

共 31 条

[1]

Bates D.R., ApJ, 306, (1986)

[2]

Baulch D.L., Et al., J. Phys. Chem. Ref. Data, 21, (1992)

[3]

Black J.H., Interstellar Processes, (1987)

[4]

Burton M.G., Tielens A.G.G.M., Hollenbach D.J., ApJ, 365, (1990)

[5]

Cesarsky C.J., Volk H.J., A&A, 70, (1978)

[6]

Chi X., Wolfendale A.W., J. Phys. G, 19, (1993)

[7]

Gredel R., Lepp S., Dalgarno A., Herbst E., ApJ, 347, (1989)

[8]

Giisten R., Serabyn E., Kasemann C., Schinkel A., Schneider G., Schultz A., Young K., ApJ, 402, (1993)

[9]

Herbst E., Lee H.-H., Howe D.A., Millar T.J., MNRAS, 268, (1994)

[10]

Herd C.R., Adams N.G., Smith D., ApJ, 349, (1990)

← 1 2 3 4 →