Iron K-line analysis of clusters of galaxies with the resonance scattering effect

F. Akimoto, Akihiro Furuzawa, Y. Tawara, K. Yamashita

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The spectral analysis was carried out in the central core and outer envelope region of each of 50 galaxy clusters observed with ASCA. Among them, we investigated iron K-lines of 8 targets which have large iron line intensities. Iron K-lines were separately observed as He-like K α , H-like K α by SIS and their blend and K β blended with nickel K α lines by GIS. Their energies and intensities were derived from spectral fittings of continuum and Gaussian lines in the energy range of 3-10keV. The intensity ratio of He-like K α to H-like K α has the tendency to be smaller than that estimated from a thin hot plasma model. The intensity ratio of K α to K β has the same tendency as well, and seems to be increasing from the core to the envelope for some clusters. These discrepancies would be due to the reduction of K α , especially He-like K α intensity. The optical depth of He-like iron K α is estimated to be around unity in the core, so that the line would be suppressed in the core and enhanced in the envelope by the resonance scattering effect. This observational evidence of the resonance scattering is critically important to determine the abundance and to investigate the origin of heavy elements in an intra-cluster medium (ICM).

Original languageEnglish
Pages (from-to)603-606
Number of pages4
JournalAdvances in Space Research
Volume25
Issue number3-4
DOIs
Publication statusPublished - 01-01-2000

Fingerprint

K lines
Galaxies
resonance scattering
scattering
Scattering
Iron
galaxies
iron
envelopes
tendencies
Spectrum analysis
spectral analysis
Geographic information systems
optical depth
energy
heavy elements
high temperature plasmas
nickel
optical thickness
GIS

All Science Journal Classification (ASJC) codes

  • Aerospace Engineering
  • Astronomy and Astrophysics
  • Geophysics
  • Atmospheric Science
  • Space and Planetary Science
  • Earth and Planetary Sciences(all)

Cite this

Akimoto, F. ; Furuzawa, Akihiro ; Tawara, Y. ; Yamashita, K. / Iron K-line analysis of clusters of galaxies with the resonance scattering effect. In: Advances in Space Research. 2000 ; Vol. 25, No. 3-4. pp. 603-606.
@article{07cfa2492d4d43ed9e6bdff65a2a8838,
title = "Iron K-line analysis of clusters of galaxies with the resonance scattering effect",
abstract = "The spectral analysis was carried out in the central core and outer envelope region of each of 50 galaxy clusters observed with ASCA. Among them, we investigated iron K-lines of 8 targets which have large iron line intensities. Iron K-lines were separately observed as He-like K α , H-like K α by SIS and their blend and K β blended with nickel K α lines by GIS. Their energies and intensities were derived from spectral fittings of continuum and Gaussian lines in the energy range of 3-10keV. The intensity ratio of He-like K α to H-like K α has the tendency to be smaller than that estimated from a thin hot plasma model. The intensity ratio of K α to K β has the same tendency as well, and seems to be increasing from the core to the envelope for some clusters. These discrepancies would be due to the reduction of K α , especially He-like K α intensity. The optical depth of He-like iron K α is estimated to be around unity in the core, so that the line would be suppressed in the core and enhanced in the envelope by the resonance scattering effect. This observational evidence of the resonance scattering is critically important to determine the abundance and to investigate the origin of heavy elements in an intra-cluster medium (ICM).",
author = "F. Akimoto and Akihiro Furuzawa and Y. Tawara and K. Yamashita",
year = "2000",
month = "1",
day = "1",
doi = "10.1016/S0273-1177(99)00809-1",
language = "English",
volume = "25",
pages = "603--606",
journal = "Advances in Space Research",
issn = "0273-1177",
publisher = "Elsevier Limited",
number = "3-4",

}

Iron K-line analysis of clusters of galaxies with the resonance scattering effect. / Akimoto, F.; Furuzawa, Akihiro; Tawara, Y.; Yamashita, K.

In: Advances in Space Research, Vol. 25, No. 3-4, 01.01.2000, p. 603-606.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Iron K-line analysis of clusters of galaxies with the resonance scattering effect

AU - Akimoto, F.

AU - Furuzawa, Akihiro

AU - Tawara, Y.

AU - Yamashita, K.

PY - 2000/1/1

Y1 - 2000/1/1

N2 - The spectral analysis was carried out in the central core and outer envelope region of each of 50 galaxy clusters observed with ASCA. Among them, we investigated iron K-lines of 8 targets which have large iron line intensities. Iron K-lines were separately observed as He-like K α , H-like K α by SIS and their blend and K β blended with nickel K α lines by GIS. Their energies and intensities were derived from spectral fittings of continuum and Gaussian lines in the energy range of 3-10keV. The intensity ratio of He-like K α to H-like K α has the tendency to be smaller than that estimated from a thin hot plasma model. The intensity ratio of K α to K β has the same tendency as well, and seems to be increasing from the core to the envelope for some clusters. These discrepancies would be due to the reduction of K α , especially He-like K α intensity. The optical depth of He-like iron K α is estimated to be around unity in the core, so that the line would be suppressed in the core and enhanced in the envelope by the resonance scattering effect. This observational evidence of the resonance scattering is critically important to determine the abundance and to investigate the origin of heavy elements in an intra-cluster medium (ICM).

AB - The spectral analysis was carried out in the central core and outer envelope region of each of 50 galaxy clusters observed with ASCA. Among them, we investigated iron K-lines of 8 targets which have large iron line intensities. Iron K-lines were separately observed as He-like K α , H-like K α by SIS and their blend and K β blended with nickel K α lines by GIS. Their energies and intensities were derived from spectral fittings of continuum and Gaussian lines in the energy range of 3-10keV. The intensity ratio of He-like K α to H-like K α has the tendency to be smaller than that estimated from a thin hot plasma model. The intensity ratio of K α to K β has the same tendency as well, and seems to be increasing from the core to the envelope for some clusters. These discrepancies would be due to the reduction of K α , especially He-like K α intensity. The optical depth of He-like iron K α is estimated to be around unity in the core, so that the line would be suppressed in the core and enhanced in the envelope by the resonance scattering effect. This observational evidence of the resonance scattering is critically important to determine the abundance and to investigate the origin of heavy elements in an intra-cluster medium (ICM).

UR - http://www.scopus.com/inward/record.url?scp=0040952740&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0040952740&partnerID=8YFLogxK

U2 - 10.1016/S0273-1177(99)00809-1

DO - 10.1016/S0273-1177(99)00809-1

M3 - Article

AN - SCOPUS:0040952740

VL - 25

SP - 603

EP - 606

JO - Advances in Space Research

JF - Advances in Space Research

SN - 0273-1177

IS - 3-4

ER -