Effects of jetlike explosion in SN 1987A

被引:72
作者
Nagataki, S [1 ]
机构
[1] Univ Tokyo, Sch Sci, Dept Phys, Bunkyo Ku, Tokyo 113, Japan
关键词
nuclear reactions; nucleosynthesis; abundances; pulsars : general; stars : neutron;
D O I
10.1086/313317
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We study the effects of jetlike explosion in SN 1987A. Calculations of the explosive nucleosynthesis and the matter mixing in a jetlike explosion are performed, and their results are compared with the observations of SN 1987A. It is shown that the jetlike explosion model is favored because the radioactive nuclei Ti-44 is produced in a sufficient amount to explain the observed luminosity at 3600 days after the explosion. This is because the active alpha-rich freeze-out takes place behind the strong shock wave in the polar region. It is also shown that the observed line profiles of Fe [II] are well reproduced by the jetlike explosion model. In particular, the fast-moving component traveling at 3000-4000 km s(-1) is well reproduced; it has not been reproduced by the spherical explosion models. Moreover, we conclude that the favored degree of a jetlike explosion to explain the tail of the light curve is consistent with the one favored in the calculation of the matter mixing. The concluded ratio of the velocity along to the polar axis relative to that in the equatorial plane at the Si/Fe interface is similar to 2:1. This conclusion will give good constraints on the calculations of the dynamics of the collapse-driven supernova. We also found that the required amplitude for the initial velocity fluctuations as a seed of the matter mixing is similar to 30%. This result supports the idea that the origin of the fluctuations is the dynamics of the core collapse rather than the convection in the progenitor. The asymmetry of the observed line profiles of Fe [II] can be explained when the assumption of the equatorial symmetry of the system is removed, which can be caused by the asymmetry of the jetlike explosion with respect to the equatorial plane. In the case of SN 1987A, the jet on the north pole has to be stronger than that on the south pole in order to reproduce the observed asymmetric line profiles. Such an asymmetry may also be the origin of the pulsar kick. When we believe some theories that cause such an asymmetric explosion, the proto-neutron star born in SN 1987A will be moving in the southern part of the remnant.
引用
收藏
页码:141 / 157
页数:17
相关论文
共 121 条
[1]   Three-laboratory measurement of the 44Ti half-life [J].
Ahmad, I ;
Bonino, G ;
Castagnoli, GC ;
Fischer, SM ;
Kutschera, W ;
Paul, M .
PHYSICAL REVIEW LETTERS, 1998, 80 (12) :2550-2553
[2]  
AITKEN DK, 1989, MNRAS, V235, P19
[3]   HALF-LIVES OF TI-44 AND BI-207 [J].
ALBURGER, DE ;
HARBOTTLE, G .
PHYSICAL REVIEW C, 1990, 41 (05) :2320-2324
[4]  
Arnett D., 1996, Supernovae and Nucleosynthesis: An Investigation of the History of Matter from the Big Bang to the Present
[5]  
ARNETT WD, 1989, APJ, V341, pL63
[6]   SHOCK-WAVES AND NUCLEOSYNTHESIS IN TYPE-II SUPERNOVAE [J].
AUFDERHEIDE, MB ;
BARON, E ;
THIELEMANN, FK .
ASTROPHYSICAL JOURNAL, 1991, 370 (02) :630-642
[7]  
BANDIERA R, 1984, ASTRON ASTROPHYS, V139, P368
[8]   CONVECTION, NUCLEOSYNTHESIS, AND CORE COLLAPSE [J].
BAZAN, G ;
ARNETT, D .
ASTROPHYSICAL JOURNAL, 1994, 433 (01) :L41-L43
[9]   Two-dimensional hydrodynamics of pre-core collapse: Oxygen shell burning [J].
Bazan, G ;
Arnett, D .
ASTROPHYSICAL JOURNAL, 1998, 496 (01) :316-332
[10]   THE SUPERNOVA SHOCK [J].
BETHE, HA .
ASTROPHYSICAL JOURNAL, 1995, 449 (02) :714-726