1 / 13

Supernova Nucleosynthesis and Extremely Metal-Poor Stars

Supernova Nucleosynthesis and Extremely Metal-Poor Stars. Nozomu Tominaga (Univ. of Tokyo). Collaborators: H.Umeda, K.Maeda, N.Iwamoto, K.Nomoto. OMEG07, 4-7 Dec. 2007, Hokkaido Univ. Core-Collapse SNe. Core collapse Compact object n emission Energy deposition. Massive Star (>10M 8 )

doak
Download Presentation

Supernova Nucleosynthesis and Extremely Metal-Poor Stars

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Supernova Nucleosynthesis and Extremely Metal-Poor Stars Nozomu Tominaga (Univ. of Tokyo) Collaborators: H.Umeda, K.Maeda, N.Iwamoto, K.Nomoto OMEG07, 4-7 Dec. 2007, Hokkaido Univ.

  2. Core-Collapse SNe Core collapse Compact object n emission Energy deposition Massive Star (>10M8) e--capture SNe (8-10M8) H He C O Si Fe

  3. CCSN Explosion Mechanism Black hole-forming SNe Rapidly-rotating star Jet Core collapse Accretion disk Accretion disk Neutrino Magnetic field Jet formation Jet-induced explosion 35M8 star (MacFadyen et al. 99)

  4. Explosive Nucleosynthesis Post-shock Temperature T∝R-3/4E1/4 Shock Propagation T[109K] Fe Complete Si burning Fe,α,Ni,Zn,Co,V Incomplete Si burning Fe,Si,Cr,Mn O burning Si 5 4 R ejecta NS/BH 3

  5. Supernova-induced star formation (e.g., Cioffi et al. 1988) The metal-poor stars are formed by the SN shock compression from the mixture of the materials ejected from SN (Fe, C, O, etc.) and swept-up by shockwave (H, He). H, He Fe, C, O, Mg, Si, Ca The abundance patterns of EMP stars reflect nucleosynthesis in the parent star and SN.

  6. Jet-induced explosion Jet Mms=40M8, Z=0 Edep=1.5x1052erg Jet BH/NS BH cf. “Collapsar”(e.g., MacFadyen et al. 01) Magnetorotational Supernovae (e.g., Moiseenko et al. 06) . Edep[erg/s]: Energy deposition rate parameter (NT et al. 07)

  7. Dependence: energy deposition rates . Edep↓: Infall↑ M(Fe)↓ [C/Fe]↑ . . Edep=120x1051erg/s Edep=1.5x1051erg/s H H He He Infall O/C O/C O/Mg Si Infall Fe

  8. Results: M(Fe) & [C/X] . . Larger Edep Larger Edep Larger M(Fe) Smaller M(Fe) Explosive Jet HMP EMP stars CEMP stars UMP stars HMP stars UMP [C/Mg] CEMP [C/Fe] EMP Higher [C/Fe] for smaller M(Fe) (tending to be lower [Fe/H]) [C/O]

  9. Abundance patterns . EMP stars Edep=30x1051erg/s M(56Ni)~0.1M8 . CEMP stars Edep=3x1051erg/s M(56Ni)~8x10-4M8 . HMP stars Edep=0.5-1.5x1051erg/s M(56Ni)~3-4x10-6M8

  10. Summary-1 EMP stars SNe with various E and Mms (NT, Umeda, Nomoto 07) UMP HMP CEMP . EMP When Edep is large EMP, CEMP, (UMP), HMP stars Jet-induced SNe with various Edep .

  11. A peculiar EMP stars: HE1424-0241 Si He Fe Mg [Mg/Si]~1.4 Si Jet Fe A possible explanation Angular dependent yield (NT 07 arXiv:0711.4815) Abundance mixing due to the ISM interaction?? R/1014 [cm] • A peculiar Si-deficient star (Cohen et al. 07)

  12. Summary-1 EMP stars SNe with various E and Mms (NT, Umeda, Nomoto 07) UMP HMP CEMP . EMP When Edep is large EMP, CEMP, (UMP), HMP stars Jet-induced SNe with various Edep . Angular dependence??

  13. Summary-2 • Abundance patterns of the EMP stars • Jet-induced explosion of stars as massive as SNe in the present days (Mms <100M8) • Variations of the EMP stars • Variation of energy deposition rate • Higher [C/Fe] tends to be realized for lower [Fe/H]. • Variation of progenitor mass and explosion energy • Angular dependence → Outliers of the EMP stars • According to the simulation of First Star formation (e.g., Yoshida et al. 06) • First stars are more massive than 100M8 • Second stars with 40M8 are formed from primordial gas?

More Related