Published September 1989
| Version v1
Report
An implication of the IR identification of PAHs: the heating of the diffuse is gas
- 1. Paris-7 Univ., 75 (France)
- 2. Paris-11 Univ., 91 - Orsay (France). Lab. de Physico-Chimie des Rayonnements
Description
The HI diffuse medium as seen by 21-cm emission absorption observations shows essentially 2 phases in pressure equilibrium: the cold medium with T ∼ 40 to 400 K and nH = 50 cm-3 and the warm medium with T = 6000 to 8000 K nH = 5 10-1 cm-3. The cooling mechanisms for the HI medium are now well understood but the heating required remains unaccounted for. We have estimated the heating due to photoionization of PAHs: it is found that PAHs dominate the heating of the cold phase and that it would represent an important fraction of that required for the warm phase
Additional details
Publishing Information
- Imprint Title
- Infrared spectroscopy in astronomy
- Imprint Pagination
- 613 p.
- Journal Page Range
- p. 225-232.
- Report number
- ESA-SP--290
Conference
- Title
- 22. ESLAB Symposium on infrared spectroscopy in astronomy.
- Dates
- 7-9 Dec 1988.
- Place
- Salamanca (Spain).
INIS
- Country of Publication
- France
- Country of Input or Organization
- France
- INIS RN
- 21088765
- Subject category
- S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
- Resource subtype / Literary indicator
- Conference
- Descriptors DEI
- AROMATICS; H1 REGIONS; INFRARED RADIATION; PHOTOIONIZATION
- Descriptors DEC
- COSMIC RADIO SOURCES; ELECTROMAGNETIC RADIATION; IONIZATION; ORGANIC COMPOUNDS; RADIATIONS