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Title: Inner-Shell Absorption Lines of Fe 6-Fe 16: a Many-Body Perturbation Theory Approach

Abstract

We provide improved atomic calculation of wavelengths, oscillator strengths, and autoionization rates relevant to the 2 -> 3 inner-shell transitions of Fe VI-XVI, the so-called Fe M-shell unresolved transition array (UTA). A second order many-body perturbation theory is employed to obtain accurate transition wavelengths, which are systematically larger than previous theoretical results by 15-45 mA. For a few transitions of Fe XVI and Fe XV where laboratory measurements exist, our new wavelengths are accurate to within a few mA. Using these new calculations, the apparent discrepancy in the velocities between the Fe M-shell UTA and other highly ionized absorption lines in the outflow of NGC 3783 disappears. The oscillator strengths in our new calculation agree well with the previous theoretical data, while the new autoionization rates are significantly larger, especially for lower charge states. We attribute this discrepancy to the missing autoionization channels in the previous calculation. The increased autoionization rates may slightly affect the column density analysis of the Fe M-shell UTA for sources with high column density and very low turbulent broadening. The complete set of atomic data is provided as an electronic table.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
878002
Report Number(s):
SLAC-PUB-11632
astro-ph/0512410; TRN: US200609%%11
DOE Contract Number:
AC02-76SF00515
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; IRON; AUTOIONIZATION; CHARGE STATES; M SHELL; OSCILLATOR STRENGTHS; PERTURBATION THEORY; ENERGY-LEVEL TRANSITIONS; Astrophysics,ASTRO

Citation Formats

Gu, Ming F., /KIPAC, Menlo Park, Holczer, Tomer, Behar, Ehud, /Technion, Kahn, Steven M., and /KIPAC, Menlo Park. Inner-Shell Absorption Lines of Fe 6-Fe 16: a Many-Body Perturbation Theory Approach. United States: N. p., 2006. Web. doi:10.2172/878002.
Gu, Ming F., /KIPAC, Menlo Park, Holczer, Tomer, Behar, Ehud, /Technion, Kahn, Steven M., & /KIPAC, Menlo Park. Inner-Shell Absorption Lines of Fe 6-Fe 16: a Many-Body Perturbation Theory Approach. United States. doi:10.2172/878002.
Gu, Ming F., /KIPAC, Menlo Park, Holczer, Tomer, Behar, Ehud, /Technion, Kahn, Steven M., and /KIPAC, Menlo Park. Tue . "Inner-Shell Absorption Lines of Fe 6-Fe 16: a Many-Body Perturbation Theory Approach". United States. doi:10.2172/878002. https://www.osti.gov/servlets/purl/878002.
@article{osti_878002,
title = {Inner-Shell Absorption Lines of Fe 6-Fe 16: a Many-Body Perturbation Theory Approach},
author = {Gu, Ming F. and /KIPAC, Menlo Park and Holczer, Tomer and Behar, Ehud and /Technion and Kahn, Steven M. and /KIPAC, Menlo Park},
abstractNote = {We provide improved atomic calculation of wavelengths, oscillator strengths, and autoionization rates relevant to the 2 -> 3 inner-shell transitions of Fe VI-XVI, the so-called Fe M-shell unresolved transition array (UTA). A second order many-body perturbation theory is employed to obtain accurate transition wavelengths, which are systematically larger than previous theoretical results by 15-45 mA. For a few transitions of Fe XVI and Fe XV where laboratory measurements exist, our new wavelengths are accurate to within a few mA. Using these new calculations, the apparent discrepancy in the velocities between the Fe M-shell UTA and other highly ionized absorption lines in the outflow of NGC 3783 disappears. The oscillator strengths in our new calculation agree well with the previous theoretical data, while the new autoionization rates are significantly larger, especially for lower charge states. We attribute this discrepancy to the missing autoionization channels in the previous calculation. The increased autoionization rates may slightly affect the column density analysis of the Fe M-shell UTA for sources with high column density and very low turbulent broadening. The complete set of atomic data is provided as an electronic table.},
doi = {10.2172/878002},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 17 00:00:00 EST 2006},
month = {Tue Jan 17 00:00:00 EST 2006}
}

Technical Report:

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