1. Type Ia and II supernovae contributions
to the metal enrichment in the intra-cluster medium
observed with Suzaku
ApJ Letter, vol. 667, L41, 2007
PASJ, vol. 59, 299, 2007
PASJ, in press, astro-ph/ ,
Kosuke Sato1,
K. Tokoi2, K. Matsusihta1, Y. Ishisaki2, N. Y. Yamasaki3,
M. Ishida3, and T. Ohashi2
1 Tokyo Univ. of Science, 2 Tokyo Metropolitan Univ., 3 ISAS/JAXA

2. Introduction – past X-ray observations –
“ ASCA ” ⇒ Dupke & White (2000), Baumgartner et al. (2005)
“ XMM ” ⇒ de Plaa et al. (2006,2007), Werner et al. (2006)
XMM
22 clusters
O in the only central region
Mg with large uncertainties
de Plaa et al. (2007)
SNe II/Ia ratio ~3.5
Poor information
from SNe II products
Suzaku
Low & stable background level
Higher sensitivity below ~1 keV
Determination of various elements from O to Fe

3. Merits of Suzaku XIS A1060 Suzaku Oxygen XMM XMM Suzaku BI FI
Superior O Line sensitivity
Suzaku BI FI
XMM
Tsunemi et al. (2006)
A1060
Oxygen
Suzaku
XMM
Low intrinsic non X-ray Background (NXB) &
Good reproducibility (～5%）
due to low orbit satellite & short focal length
High line sensitivity below ～1 keV
Suitable for extended objects, like clusters & groups

4. Selected clusters and groups
Nearby and Bright objects in early Suzaku observations
Moderate low temperature (kT<4 keV) for O measurement
Obs redshift r180（Mpc） date
A1060
AWM7
HCG62
NGC507
0.0114
0.0172
0.0145
0.0165
1.53
1.65
1.08
22/Nov./2005
5/Aug./2006
23/Jan./2006
28/Jul./2006
Sampling ranging: Groups (~1.5 keV) ~ Clusters (~4 keV)
Not including in de Plaa et al. (2007)
Measurements of the metal abundance and
distributions to ~0.3 r180
Analysis methods :
See in Sato et al. (2007a, 2007b) & Tokoi et al. (2007)

5. X-ray Images with Suzaku
Smoothed with σ = 16″gaussian, Exposure time corrected
Cosmic X-ray Background, Non X-ray Background subtracted
A1060
AWM7
keV
10′
(140 kpc）
(210 kpc)
0.1 r180
HCG62
keV
(178 kpc)
0.1 r180
NGC507
keV
(200 kpc)
0.1 r180
10′
10′

6. O & Mg measurements with Suzaku
OVII
OVIII O Mg

7. Metal distributions 1 From O to Fe radial profiles
AWM7
A1060
HCG62
NGC507 1
From O to Fe radial profiles
（solar: Anders & Grevesse 1989）
Comparison the metals to Fe ratio
Si, S / Fe : fairly flat ~1 – 2
O, Mg / Fe : increase with radius?
⇒ Difference from SNe Ia or II ? 1
（solar）
0.1
Radial profiles of Fe
r / r180
O/Fe 1 1 1
Mg/Fe
Si/Fe
r / r180
r / r180
r / r180

8. Numbers of Type Ia and II supernovae
How each metal is synthesized with SN Ia & II ?
⇒ Estimation of the numbers of SN Ia & II （NIa, NII）
Fit the amount of metals with nucleosynthesis model
SNe nucleosynthesis model
SNe Ia ： W7 model （Nomoto et al. 1984）
WDD1 or 2 model（Iwamoto et al. 1999）
SNe II : 10 – 50 M (Salpeter Initial Mass Function)
Progenitor Metallicity Z = 0.02（Nomoto et al. 2006）
ψ（M） ∝ M -2.35

9. Results : 1 Metal mass （M） AWM7 HCG62 （Ne） NGC507 A1060 O Mg Si S Fe
W7, W7,< 0.1 r180
WDD1, WDD2
AWM7 O
（Ne） Mg Si S Fe
HCG62
NGC507

10. Results : 2 AWM7（3.5 keV） χ2 / d.o.f. = 15.9 / 3 A1060（3 keV）
W7, W7,< 0.1 r180
WDD1, WDD2
AWM7（3.5 keV）
χ2 / d.o.f. = 15.9 / 3
A1060（3 keV）
χ2 / d.o.f. = 8.5 / 3
Ratio
HCG62（1.5 keV）
χ2 / d.o.f. = 3.0 / 3
NGC507（1.5 keV）
χ2 / d.o.f. = 11.7 / 3 O Mg S Fe
（Ne） Si
Fits are not acceptable….

11. Results : 3 AWM7（3.5 keV） A1060（3 keV） Fractions from SNe Ia
0.8
0.6
0.4
AWM7（3.5 keV）
W7, W7,< 0.1 r180
WDD1, WDD2
A1060（3 keV）
0.8
0.6
0.4
Fractions from SNe Ia
HCG62（1.5 keV）
0.8
0.6
0.4
0.8
0.6
0.4
NGC507（1.5 keV） O Mg Si S Fe
~3/4 of Fe from SNe Ia

12. Numbers and Ratio of SNe Ia & II
SNe II
SNe Ia（W7） ＋
3.5
SNe II/Ia ratio
Numbers of SNe Ia & II
A1060
AWM7
HCG62
NGC507
A1060
AWM7
HCG62
NGC507
Gas mass（M）
Gas mass（M）
Numbers of SNe Ia & II are propose to the gas mass
SNe II/Ia Ratio: ~3.5
cf.
Clusters (XMM ; de Plaa et al. 2007): ~3.5
Our Galaxy (Tsujimoto et al. 1995): ~6.7
LMC & SMC (Tsujimoto et al. 1995): 3.3 – 5

13. Comparison of Numbers of SNe II
Number of SNe II expected from Star Formation Rate
of Hubble Deep Field (Madau et al. 1998)
Numbers of SNe II expected from the metal mass
observed with Suzaku
Normalized by K-band（2MASS） luminosities
Now, only the metals
in the ICM, not including
in the stars (galaxies)
AWM7
HDF
NII / LK （LK-1）
A1060
Considering in the stars,
the results with X-ray
increase by factor ~2
Numbers of SNe II（Mpc-3）

14. Mass-to-Light Ratio: MLR
Metals are synthesized in stars (galaxies):
Compare Mmetal, < R ( in units of M )
With B-band luminosity LB, < R ( in units of L )
Also use K-band luminosity
because of the comparison
of galaxy type
Fe mass / B-band Luminosity
Mmetal, < R
LB or K, < R
MLR = M L
Makishima et al. (2001)
Temperature (keV) ∝ size of system
Oxygen Mass-to-Light Ratio: OMLR
Magnesium Mass-to-Light Ratio: MMLR
Iron Mass-to-Light Ratio: IMLR
First time

15. With K-band, close to the MLR between clusters and groups
MLR（B-band vs. K-band）Sato et al. in preparation
AWM7
A1060
HCG62
NGC507
AWM7
A1060
HCG62
NGC507
MMLR
AWM7
A1060
HCG62
NGC507
IMLR
MLR
OMLR
r / r180
r / r180
r / r180
With K-band, close to the MLR between clusters and groups
B-band K-band
AWM7
A1060
HCG62
NGC507
AWM7
A1060
HCG62
NGC507
AWM7
A1060
HCG62
NGC507
MLR
OMLR
IMLR
MMLR
r / r180
r / r180
r / r180

16. Summary Conducted spatially resolved spectral analysis
of clusters & groups with Suzaku
Measurements of the metals (O to Fe) to ~0.3 r180
Assuming nucleosynthesis models, we determined
the numbers of SNe II in the past using the metal
masses of O, Mg, Si, S, and Fe
SNe II / Ia number ratio ~3.5
The Numbers from X-ray observations are consistent
with the number from SFR in HDF
Measurements of OMLR & MMLR for the first time
MLRs with K-band are close between clusters & groups