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Title: Tracing Gas Motions in the Centaurus Cluster

Abstract

We apply the stochastic model of iron transport developed by Rebusco et al. (2005) to the Centaurus cluster. Using this model, we find that an effective diffusion coefficient D in the range 2 x 10{sup 28} - 4 x 10{sup 28} cm{sup 2}s{sup -1} can approximately reproduce the observed abundance distribution. Reproducing the flat central profile and sharp drop around 30-70 kpc, however, requires a diffusion coefficient that drops rapidly with radius so that D > 4 x 10{sup 28} cm{sup 2}s{sup -1} only inside about 25 kpc. Assuming that all transport is due to fully-developed turbulence, which is also responsible for offsetting cooling in the cluster core, we calculate the length and velocity scales of energy injection. These length scales are found to be up to a factor of {approx} 10 larger than expected if the turbulence is due to the inflation and rising of a bubble. We also calculate the turbulent thermal conductivity and find it is unlikely to be significant in preventing cooling.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
876755
Report Number(s):
SLAC-PUB-11723
astro-ph/0602466; TRN: US200606%%726
DOE Contract Number:
AC02-76SF00515
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; STAR CLUSTERS; ABUNDANCE; DIFFUSION; IRON; THERMAL CONDUCTIVITY; TRANSPORT; TURBULENCE; GASES; Astrophysics,ASTRO

Citation Formats

Graham, James, Fabian, A.C., Sanders, J.S., /Cambridge U., Inst. of Astron., Morris, R.G., and /Cambridge U., Inst. of Astron. /KIPAC, Menlo Park. Tracing Gas Motions in the Centaurus Cluster. United States: N. p., 2006. Web. doi:10.2172/876755.
Graham, James, Fabian, A.C., Sanders, J.S., /Cambridge U., Inst. of Astron., Morris, R.G., & /Cambridge U., Inst. of Astron. /KIPAC, Menlo Park. Tracing Gas Motions in the Centaurus Cluster. United States. doi:10.2172/876755.
Graham, James, Fabian, A.C., Sanders, J.S., /Cambridge U., Inst. of Astron., Morris, R.G., and /Cambridge U., Inst. of Astron. /KIPAC, Menlo Park. Wed . "Tracing Gas Motions in the Centaurus Cluster". United States. doi:10.2172/876755. https://www.osti.gov/servlets/purl/876755.
@article{osti_876755,
title = {Tracing Gas Motions in the Centaurus Cluster},
author = {Graham, James and Fabian, A.C. and Sanders, J.S. and /Cambridge U., Inst. of Astron. and Morris, R.G. and /Cambridge U., Inst. of Astron. /KIPAC, Menlo Park},
abstractNote = {We apply the stochastic model of iron transport developed by Rebusco et al. (2005) to the Centaurus cluster. Using this model, we find that an effective diffusion coefficient D in the range 2 x 10{sup 28} - 4 x 10{sup 28} cm{sup 2}s{sup -1} can approximately reproduce the observed abundance distribution. Reproducing the flat central profile and sharp drop around 30-70 kpc, however, requires a diffusion coefficient that drops rapidly with radius so that D > 4 x 10{sup 28} cm{sup 2}s{sup -1} only inside about 25 kpc. Assuming that all transport is due to fully-developed turbulence, which is also responsible for offsetting cooling in the cluster core, we calculate the length and velocity scales of energy injection. These length scales are found to be up to a factor of {approx} 10 larger than expected if the turbulence is due to the inflation and rising of a bubble. We also calculate the turbulent thermal conductivity and find it is unlikely to be significant in preventing cooling.},
doi = {10.2172/876755},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2006},
month = {Wed Mar 01 00:00:00 EST 2006}
}

Technical Report:

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