Stimulated amplification in an astrophysical plasma: An FeII space laser in gas condensation in the vicinity of eta carinae
(2005) In Laser Physics 15(7). p.939-946- 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 nonequilibrium. 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 "pseudometastable" states (at medium excitation) in the complex spectrum of Fe 11, 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 H Ly-alpha radiation at a high effective temperature. In conclusion, we... (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 nonequilibrium. 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 "pseudometastable" states (at medium excitation) in the complex spectrum of Fe 11, 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 H Ly-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/231990
- author
- Johansson, Sveneric LU and Letokhov, Vladilen LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Laser Physics
- volume
- 15
- issue
- 7
- pages
- 939 - 946
- publisher
- Interperiodica
- external identifiers
-
- wos:000230682100003
- scopus:25844457816
- ISSN
- 1054-660X
- language
- English
- LU publication?
- yes
- id
- 1ffcf22f-6875-4aab-afb4-1a08fded2133 (old id 231990)
- date added to LUP
- 2016-04-01 15:36:14
- date last changed
- 2024-01-10 17:18:21
@article{1ffcf22f-6875-4aab-afb4-1a08fded2133, 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 nonequilibrium. 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 "pseudometastable" states (at medium excitation) in the complex spectrum of Fe 11, 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 H Ly-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 = {{1054-660X}}, language = {{eng}}, number = {{7}}, pages = {{939--946}}, publisher = {{Interperiodica}}, series = {{Laser Physics}}, title = {{Stimulated amplification in an astrophysical plasma: An FeII space laser in gas condensation in the vicinity of eta carinae}}, volume = {{15}}, year = {{2005}}, }