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Title: Phenomenological Theory of the Photoevaporation Front Instability

Abstract

The dynamics of photoevaporated molecular clouds is determined by the ablative pressure acting on the ionization front. An important step in the understanding of the ensuing motion is to develop the linear stability theory for the initially flat front. Despite the simplifications introduced by the linearization, the problem remains quite complex and still draws a lot of attention. The complexity is related to the large number of effects that have to be included in the analysis: acceleration of the front, possible temporal variation of the intensity of the ionizing radiation, the tilt of the radiation flux with respect to the normal to the surface, and partial absorption of the incident radiation in the ablated material. In this paper, we describe a model where all these effects can be taken into account simultaneously, and a relatively simple and universal dispersion relation can be obtained. The proposed phenomenological model may prove to be a helpful tool in assessing the feasibility of the laboratory experiments directed towards scaled modeling of astrophysical phenomena.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
907833
Report Number(s):
UCRL-JRNL-220524
Journal ID: ISSN 0004-640X; APSSBE; TRN: US0703329
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysics and Space Science, vol. 307, no. 1-3, January 31, 2007, pp. 173; Journal Volume: 307; Journal Issue: 1-3
Country of Publication:
United States
Language:
English
Subject:
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; 70 PLASMA PHYSICS AND FUSION; ABSORPTION; ACCELERATION; CLOUDS; DISPERSION RELATIONS; INSTABILITY; IONIZATION; IONIZING RADIATIONS; RADIATION FLUX; RADIATIONS; SIMULATION; STABILITY

Citation Formats

Ryutov, D D, Kane, J O, Mizuta, A, Pound, M W, and Remington, B A. Phenomenological Theory of the Photoevaporation Front Instability. United States: N. p., 2006. Web.
Ryutov, D D, Kane, J O, Mizuta, A, Pound, M W, & Remington, B A. Phenomenological Theory of the Photoevaporation Front Instability. United States.
Ryutov, D D, Kane, J O, Mizuta, A, Pound, M W, and Remington, B A. Mon . "Phenomenological Theory of the Photoevaporation Front Instability". United States. doi:. https://www.osti.gov/servlets/purl/907833.
@article{osti_907833,
title = {Phenomenological Theory of the Photoevaporation Front Instability},
author = {Ryutov, D D and Kane, J O and Mizuta, A and Pound, M W and Remington, B A},
abstractNote = {The dynamics of photoevaporated molecular clouds is determined by the ablative pressure acting on the ionization front. An important step in the understanding of the ensuing motion is to develop the linear stability theory for the initially flat front. Despite the simplifications introduced by the linearization, the problem remains quite complex and still draws a lot of attention. The complexity is related to the large number of effects that have to be included in the analysis: acceleration of the front, possible temporal variation of the intensity of the ionizing radiation, the tilt of the radiation flux with respect to the normal to the surface, and partial absorption of the incident radiation in the ablated material. In this paper, we describe a model where all these effects can be taken into account simultaneously, and a relatively simple and universal dispersion relation can be obtained. The proposed phenomenological model may prove to be a helpful tool in assessing the feasibility of the laboratory experiments directed towards scaled modeling of astrophysical phenomena.},
doi = {},
journal = {Astrophysics and Space Science, vol. 307, no. 1-3, January 31, 2007, pp. 173},
number = 1-3,
volume = 307,
place = {United States},
year = {Mon Apr 10 00:00:00 EDT 2006},
month = {Mon Apr 10 00:00:00 EDT 2006}
}
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