Stimulated amplification under spatially nonhomogeneous conditions: An astrophysical FeII laser in the vicinity of eta carinae
(2005) In Physica Scripta T120. p.99-104- Abstract
- We consider the conditions necessary for the development of an inverted population among the energy levels of free atoms in a medium exposed to radiation in spectral non- equilibrium. In particular, we focus on monochromatic radiation occurring as a result of an accidental wavelength coincidence between a pumping emission line and a pumped absorption line in two different elements. We examine especially the influence of "pseudo-metastable" states ( at medium excitation) in the complex spectrum of Fe II, which cause a "bottleneck" in the radiative decay leading to an inverted level population. We also discuss the effect of "spectral compression" of the Lyman continuum into HLy alpha radiation at a high effective temperature. In conclusion... (More)
- We consider the conditions necessary for the development of an inverted population among the energy levels of free atoms in a medium exposed to radiation in spectral non- equilibrium. In particular, we focus on monochromatic radiation occurring as a result of an accidental wavelength coincidence between a pumping emission line and a pumped absorption line in two different elements. We examine especially the influence of "pseudo-metastable" states ( at medium excitation) in the complex spectrum of Fe II, which cause a "bottleneck" in the radiative decay leading to an inverted level population. We also discuss the effect of "spectral compression" of the Lyman continuum into HLy alpha radiation at a high effective temperature. In conclusion we describe those differences between microwave astrophysical masers (APM) and optical astrophysical lasers (APL) that make the latter a more rare phenomenon in Nature. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/208461
- author
- Johansson, Sveneric LU and Letokhov, Vladilen LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physica Scripta
- volume
- T120
- pages
- 99 - 104
- publisher
- IOP Publishing
- external identifiers
-
- wos:000236907000017
- scopus:42349106965
- ISSN
- 0031-8949
- DOI
- 10.1088/0031-8949/2005/T120/015
- language
- English
- LU publication?
- yes
- id
- 0d52438b-085a-4872-b283-3fee12dbcbd1 (old id 208461)
- date added to LUP
- 2016-04-01 11:51:58
- date last changed
- 2024-01-07 23:27:37
@article{0d52438b-085a-4872-b283-3fee12dbcbd1,
abstract = {{We consider the conditions necessary for the development of an inverted population among the energy levels of free atoms in a medium exposed to radiation in spectral non- equilibrium. In particular, we focus on monochromatic radiation occurring as a result of an accidental wavelength coincidence between a pumping emission line and a pumped absorption line in two different elements. We examine especially the influence of "pseudo-metastable" states ( at medium excitation) in the complex spectrum of Fe II, which cause a "bottleneck" in the radiative decay leading to an inverted level population. We also discuss the effect of "spectral compression" of the Lyman continuum into HLy alpha radiation at a high effective temperature. In conclusion we describe those differences between microwave astrophysical masers (APM) and optical astrophysical lasers (APL) that make the latter a more rare phenomenon in Nature.}},
author = {{Johansson, Sveneric and Letokhov, Vladilen}},
issn = {{0031-8949}},
language = {{eng}},
pages = {{99--104}},
publisher = {{IOP Publishing}},
series = {{Physica Scripta}},
title = {{Stimulated amplification under spatially nonhomogeneous conditions: An astrophysical FeII laser in the vicinity of eta carinae}},
url = {{http://dx.doi.org/10.1088/0031-8949/2005/T120/015}},
doi = {{10.1088/0031-8949/2005/T120/015}},
volume = {{T120}},
year = {{2005}},
}