| Project/Area Number |
16540211
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Astronomy
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
IZUMI Hachisu The University of Tokyo, University of TokyoSchool of Arts and Sciences, Associate Professor (90135533)
|
|---|
| Project Period (FY) |
2004 – 2007
|
| Project Status |
Completed (Fiscal Year 2007)
|
| Budget Amount *help |
¥3,670,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥270,000)
Fiscal Year 2007: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2006: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2005: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2004: ¥900,000 (Direct Cost: ¥900,000)
|
|---|
| Keywords | Type Ia supernovae / Evolution of binaries / Supersoft X-rav sources / Chemical evolution of galaxies / mass-accreting white dwarfs / Nova winds / Standard candles / Cosmic parameters / 超軟X線源 / 白色矮星 / 新星爆発 / 爆燃波の伝播 / 新星の光度曲線 / 超新星 / 超新星爆発 / 元素合成 / 鉄の起源 / 宇宙膨張 |
|---|
| Research Abstract |
We present new evolutionary models for Type Ia supernova (SN Ia) progenitors, introducing the mass-stripping effect on a main-sequence (MS) or slightly evolved companion star by winds from a mass-accreting white dwarf (WD). The mass stripping attenuates the rate of mass transfer from the companion to the WD. As a result, a very massive MS companion can avoid forming a common envelope and thus can increase the WD mass up until the SN Ia explosion. Including the mass-stripping effect, we follow binary evolutions of various WD + MS systems and obtain the parameter region in the initial donor mass-orbital period plane in which SNe Ia occur. The newly obtained SN Ia region extends to donor masses of 6-7 Msolar, although its extension depends on the efficiency of the mass-stripping effect. The stripped matter would mainly be distributed on the orbital plane and would form very massive circumstellar matter (CSM) around the SN Ia progenitor. This can explain the massive CSM around the Type Ia/Iin(Iia) supernovae SN 2002ic and SN 2005gj, as well as the tenuous CSM around the normal Type Ia supernova SN 2006X. Our new model suggests the presence of very young(<〜10^8 yr) populations of Sne Ia, which is consistent with recent observational indications of young-population Sne Ia.
|
