An ASCA study of the heavy-element distribution in clusters of galaxies

被引:139
作者
Finoguenov, A
David, LP
Ponman, TJ
机构
[1] Inst Astrophys, D-14882 Potsdam, Germany
[2] Moscow Space Res Inst, Moscow 117810, Russia
[3] Smithsonian Astrophys Observ, Cambridge, MA 02138 USA
[4] Univ Birmingham, Birmingham B15 2TT, W Midlands, England
关键词
galaxies : abundances; galaxies : clusters : general; galaxies : evolution; intergalactic medium; supernovae : general; X-rays : galaxies;
D O I
10.1086/317173
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We perform a spatially resolved X-ray spectroscopic study of a set of 11 relaxed clusters of galaxies observed by the ROSAT/PSPC and ASCA/SIS. Using a method, which corrects for the energy-dependent effects of the ASCA point-spread function based on ROSAT images, we constrain the spatial distribution of Ne, Si, S, and Fe in each cluster. Theoretical prescriptions for the chemical yields of Types Ia and II supernovae then allow determination of the Fe enrichment from both types of supernovae as a function of radius within each cluster. Using optical measurements from the literature, we also determine the iron mass-to-light ratio (IMLR) separately for Fe synthesized in both types of supernovae. For clusters with the best photon statistics, we find that the total Fe abundance decreases significantly with radius while the Si abundance is either flat or decreases less rapidly, resulting in an increasing Si/Fe ratio with radius. This result indicates a greater predominance of Type II supernova (SN) enrichment at large radii in clusters. On average, the IMLR synthesized within Type II SNe increases with radius within clusters, while the IMLR synthesized within Type Ia SNe decreases. At a fixed radius of 0.4 R-virial there is also a factor of 5 increase in the IMLR synthesized by Type II SNe between groups and clusters. This suggests that groups expelled as much as 90% of the Fe synthesized within Type II SNe at early times. All of these results are consistent with a scenario in which the gas was initially heated and enriched by Type II SN-driven galactic winds. Because of the high entropy of the preheated gas, SN II products are only weakly captured in groups. Gravitationally bound gas was then enriched with elements synthesized by Type Ia supernovae as gas-rich galaxies accreted onto clusters and were stripped during passage through the cluster core via density-dependent mechanisms (e.g., ram pressure ablation, galaxy harassment, etc.). We suggest that the high Si/Fe ratios in the outskirts of rich clusters may arise from enrichment by Type II SNe released to the intracluster medium via galactic starburst-driven winds. Low S/Fe ratios observed in clusters suggest metal-poor galaxies as a major source of SN II products.
引用
收藏
页码:188 / 203
页数:16
相关论文
共 72 条
[21]   Mass estimates of X-ray clusters [J].
Evrard, AE ;
Metzler, CA ;
Navarro, JF .
ASTROPHYSICAL JOURNAL, 1996, 469 (02) :494-507
[22]   ASCA OBSERVATIONS OF COOLING FLOWS IN CLUSTERS OF GALAXIES [J].
FABIAN, AC ;
ARNAUD, KA ;
BAUTZ, MW ;
TAWARA, Y .
ASTROPHYSICAL JOURNAL, 1994, 436 (01) :L63-L66
[23]   SN Ia enrichment in Virgo early-type galaxies from ROSAT and ASCA observations [J].
Finoguenov, A ;
Jones, C .
ASTROPHYSICAL JOURNAL, 2000, 539 (02) :603-617
[24]   Stellar metallicities and SNIa rates in the early-type galaxy NGC 5846 from ROSAT and ASCA observations [J].
Finoguenov, A ;
Jones, C ;
Forman, W ;
David, L .
ASTROPHYSICAL JOURNAL, 1999, 514 (02) :844-855
[25]   Constraining the role of Type Ia and Type II supernovae in galaxy groups by spatially resolved analysis of ROSAT and ASCA observations [J].
Finoguenov, A ;
Ponman, TJ .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1999, 305 (02) :325-337
[26]  
FINOGUENOV A, 2000, UNPUB APJ
[27]   ASCA measurements of silicon and iron abundances in the intracluster medium [J].
Fukazawa, Y ;
Makishima, K ;
Tamura, T ;
Ezawa, H ;
Xu, HG ;
Ikebe, Y ;
Kikuchi, K ;
Ohashi, T .
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 1998, 50 (01) :187-193
[28]   Supernovae types Ia/II and intracluster medium enrichment [J].
Gibson, BK ;
Loewenstein, M ;
Mushotzky, RF .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1997, 290 (04) :623-628
[29]   OPTICAL RADII OF GALAXY CLUSTERS [J].
GIRARDI, M ;
BIVIANO, A ;
GIURICIN, G ;
MARDIROSSIAN, F ;
MEZZETTI, M .
ASTROPHYSICAL JOURNAL, 1995, 438 (02) :527-538
[30]   INFALL OF MATTER INTO CLUSTERS OF GALAXIES AND SOME EFFECTS ON THEIR EVOLUTION [J].
GUNN, JE ;
GOTT, JR .
ASTROPHYSICAL JOURNAL, 1972, 176 (01) :1-&