1 / 13

Ay 123: Supernovae contd..

Ay 123: Supernovae contd. Nucleosynthesis - revisited . Fe peak. Z. Z. N. Hydrostatic equilibrium slowly builds up He 4 through Fe 56 Equilibrium `e-process’ postulated to explain `Fe peak’ abundances: more stable = more abundant. A. Decay of Nuclei and SN II light curves. Ni 56 t=6.1d

theta
Download Presentation

Ay 123: Supernovae contd..

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. Ay 123: Supernovae contd..

  2. Nucleosynthesis - revisited Fe peak Z Z N Hydrostatic equilibrium slowly builds up He4 through Fe56 Equilibrium `e-process’ postulated to explain `Fe peak’ abundances: more stable = more abundant A

  3. Decay of Nuclei and SN II light curves Ni56 t=6.1d Co56 t=77d SN1987A: McCray ARAA 31, 175 (1993)

  4. The Ring Around SN1987A Original FOC image (1990) Post-repair image 1.66” IUE observes a brightening in UV emission lines 413d after SN explosion - pre-SN ejecta is being illuminated by the explosion. Resolving the diameter of the ring gives its size and an absolute distance to the LMC Panagia et al Ap J 380, L29 (1991)

  5. Cosmological Distances from SN II P Flux, temperature & expansion velocity during `plateau phase’

  6. Hubble Diagram for SNe IIP scatter = 0.26 mag (for Ia scatter~0.20) Could detect acceleration with present technology (~15 SNIIP) More effectively probe to high z with JWST/TMT (Nugent et al 2006)

  7. SN Ia Light Curve Shape - Luminosity Correlation Reduces scatter on `Hubble diagram’ No correction Correction Phillips 1993 Ap J 413, L105; Riess et al 1995 Ap J 438, 17

  8. Host Galaxy Dependence of SNe Ia Properties Ia rate SFR/mass Width of light curve SN Ia rate correlates with specific SFR of host galaxy Light curve `stretch’ likewise correlates SN properties depend on mix of stellar population Sullivan et al Ap J 648, 868 (2006)

  9. Routes to a SNeIa in single degenerate C-O WD systems (Nomoto et al astro-ph/9907386) AGB with C+O core RG+He core WD + MS in common envelope WD + red giant Wind reduces rate Short time delay Significant time delay

  10. Cosmic Acceleration From SNe Ia Perlmutter et al 1999 • Light curve corrected peak luminosities give luminosity distance • Redshifts give cosmic expansion velocities • SNe Ia are too faint for a given redshift c.f. decelerating models!

  11. Implications of Cosmic Acceleration • Why not ? two puzzles: • expect = 8GmP4 • (10120 larger) • Why acceleration now? • M  R-3 (matter) • vac = const (vacuum) Perlmutter et al 1999 Alternative: new physics - “dark energy”: quintessence: equation of state p = w ;  R-3(1+w) dynamical scalar field w = w(t)

  12. Deep HST Survey Riess et al Ap J 659, 98 (2007)

  13. First Year Results from CFHT SNLS Astier et al A&A 447, 31 (2006) 71 homogenously studied SNe Ia w = -1.023 ± 0.090 i.e. equivalent to Cosmological Constant

More Related