H He CO ONeMg Fe Si M>8M '! " # $ % & SN1987A

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きみおいそみ
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2 H He CO ONeMg Fe Si M>8M '! " # $ % & SN1987A

3 + Wilson s Delayed explosion model (Colgate 1989).

4 Standing Accretion Shock Instability: SASI Janka et al.., 2006, 11.2M 2D weak explosion due to SASI+ν-heating π 4 θ 3π 4 0 θ π l = 1, 2 (SASI) kick velocity? τ adv > τ heat : SASI ν-heating Janka et al., astro-ph/

5 Takiwaki et al., 2004: 磁場と自転 Fig. 2. Profiles of the shock propagation in the various models: B12TW2 at 60 ms from core bounce (top left), B10.5TW1 at 127 ms (top right), B10.5TW2 at 219 ms (bottom left), and B9TW4 at 404 ms (bottom right). Profiles show color-coded contour plots of entropy (kb) per nucleon. Various profiles are found by changing the strength of the initial magnetic field and rotation. Takiwaki et al., ApJ 616 (2004) 1086 Fig.2

6 Burrows et al., 2007: Fig. 12. On the left-hand-side is a colormap of the entropy at 444ms after bounce for model M15B11DP2A1H on a 4000 km 4000 km scale. We overplot the ( B) B vector field, with a length of 15% of the width of the display corresponding to a saturation value of gcm 2 s 2. This term enters the momentum equation and thus represents the acceleration due to the magnetic field, revealing here, in particular, the role of hoop stresses in confining the jet as it moves to large distances. The right panel is the same as the left panel, but for the inner 1000 km 1000 km region. ApJ 664(2007) 416 Fig.12

7 Fig. 1. Radial trajectories of mass elements of the core of a 40 M star as a function of time after bounce in the SH model. The location of the shock wave is shown by a thick dashed line. Fig. 2. Radial trajectories of mass elements of the core of a 40 M star as a function of time after bounce in the LS model. The location of the shock wave is shown by a thick dashed line. Fig. 16. Luminosities of e (solid lines), e (dashed lines), and = (dot-dashed lines) as a function of time (t pb ) in the SH (left) and LS (right) models. left: Shen EOS, right: Lattimer-Swesty EOS 180

8 : FIG. 3 (color online). Snapshots of the density contour curves for in the equatorial plane for model SLy1414a. The solid contour curves are drawn for i g=cm 3 i 2 10 and for :5i g=cm 3 i 1 7. The dotted curves denote g=cm 3. The number in the upper left-hand side denotes the elapsed time from the beginning of the simulation in units of ms. The initial orbital period in this case is ms. Vectors indicate the local velocity field v x ;v y, and the scale is shown in the upper right-hand corner. The thick circle in the last panel of radius r 2 km denotes the location of the apparent horizon. Shibata, Taniguchi and Uryu, PRD71 (2005)

9 : Figure 1 Comparison of high-resolution spectra of HE with G64 12 and CS The latter is a double-lined spectroscopic binary. All three stars have a similar effective temperature and gravity. In HE we note the absence of the Fe I line at 393 nm together with the appearance of CH lines. Our best fit for the Ca II K (l ¼ nm) and CH band abundances is plotted in red. Additional CH fits (in red) for our carbon abundance [C/Fe] ¼ 4.1^0.2 dex are shown as well. The inset shows our strongest detected Fe I line (0.64 pm equivalent width) at 386 nm in the Subaru data from which we derive [Fe/H] non-lte ¼ 25.4^0.2. From our medium-resolution spectrum we initially estimated [Fe/H] ¼ 24.0 for HE using the apparent strength of the Ca II K line index KP of Beers et al. 21 and an approximate colour. The high-resolution data revealed the presence of strong interstellar Ca II K that had not been resolved at the lower resolution. See the prominent feature blueward of the Ca II K line. The interstellar Ca is consistent with a colour excess of E(B 2 V) ¼ 0.08 along the line of sight to HE The presence of CH lines near the Ca II K line in HE caused a similar problem in the initial recognition of its extreme metal-deficiency. These effects should be taken into account in future searches for more stars with similar heavy-element deficiency. Our high-resolution (resolving power R ¼ l/dl ¼ 50,000), high signal-tonoise ratio (S/N ¼ 160 per pixel at 400 nm) data cover the wavelength range of 304 to 674 nm. Figure 2 Abundance patterns of HE (subgiant solution, filled circles) and HE (open squares). Typical 1-j errors of 0.2 dex are shown in the plot. Upper limits are indicated by an arrow. We adopt the same non-lte corrections for both stars 22, which lead to the modification of the published abundances of HE Consequently, we adopt [Fe/H] non-lte ¼25.2 (ref. 9) as the iron abundance for HE These two most Fe-poor stars both have very large C enhancement relative to Fe by a factor of,5,000 (HE ) and,10,000 (HE ). N/Fe is,30,000 times the solar value (considering the subgiant solution) in HE whereas it is,200 times the solar value in HE The upper limit for the O abundance of HE is [O/Fe], 4.0. Oxygen in HE has recently been determined 23 to be [O/Fe] ¼ 2.3, which is of the same order as its [N/Fe] value. These enormous overabundances in CNO elements suggest that both stars belong to a group of objects sharing a common formation scenario. HE and HE have Ca/Fe and Ti/Fe abundance ratios that are enhanced by factors of less than ten compared to the Sun. The light-element ratios Na/Fe, Mg/Fe and Al/Fe, as well as, surprisingly, Sr/Fe, are all enhanced by factors of,10 to,100 in HE Of these four elements, only Na and Mg are detected in HE with element/fe ratios close to the solar value. As for several other elements, an upper limit for Ba has been measured in both stars. The Sr/Ba ratio is crucial to identify the origin for the Sr and other heavy elements. Frebel et al., Nature 434 (2005) 871

10 : Fig. 2. Internal abundance distribution for nuclei (by mass fraction) in the Pop III 25 M R SN model for the explosion energy of E (for HE ). The distribution is similar for E (HE ). The mixing is assumed to take place in the region of M r j 5.8 M R for HE and M r j 6.3 M R for HE The mass fraction of the ejected materials with respect to the mixed fallback materials is f j5 for HE and f j4 for HE As a result, the ejecta contains j5 M R 56 Ni and 0.20 M R 12 C for HE and j5 M R 56 Ni and 0.12 M R 12 C for HE Fig. 3. Propagation of the shock wave and fallback for the HE model. The progenitor is the 25 M R star. As the shock propagates through the H envelope and breaks out of the surface, the materials in the inner region continue to decelerate and will eventually fall back onto the central remnant. The mass cut (that divides the materials fallen onto the central remnant and ejected outward) is determined by comparing the velocity (v) and the escape velocity at 10 5 seconds after the explosion. Iwamoto, Umeda, Tominaga, Nomoto and Maeda, Science 309 (2005) 451

11 ( ) SASI Mass Cut νν

Mikio Yamamoto: Dynamical Measurement of the E-effect in Iron-Cobalt Alloys. The AE-effect (change in Young's modulus of elasticity with magnetization

Mikio Yamamoto: Dynamical Measurement of the E-effect in Iron-Cobalt Alloys. The AE-effect (change in Young's modulus of elasticity with magnetization) in the annealed state of iron-cobalt alloys has been