1 The progenitor stars of core-collapse supernovae Stephen J. Smartt Astrophysics Research Centre Queen’s University Belfast Queen’s SNe & Massive star group: J. Eldridge, S. Mattila, A. Pastorello, M. Crockett, D. Young, M. Hendry, P. Dufton, C. Trundle, I. Hunter Others: J. Maund (Texas), J. Danziger (Trieste), P. Meikle (Imperial),

2 Overview Core-collapse SNe drive the chemical evolution of galaxies, and formation through feedback Test stellar evolution theory and NS/BH formation scenarios Linked to the formation of long duration GRBs Are the ideas of SNe progenitor stars correct ? Are SNe explosion and lightcurve models consistent ?

3 Credit: LOSS and T. Debosz

4 Summary of SNe types Supernovae are classified by their optical spectra No hydrogen  Type I    Si He He or Si    Ia Ib Ic ——— Hydrogen lines  Type II  Photometry/spectra properties  II-P, II-L, IIn, IIb, II-p

5 Example: HST Key project – H 0 with Cepheids Blue supergiants at 2-7Mpc from 8m telescopes - Bresolin et al. (2001) M101 NGC3621 NGC3949

6 M81 zoom in

7 First red supergiant progenitor SN2003gd discovered 2003 June 12 Normal type II-P M74 - distance 9.3  1.8 Mpc 3100s WFPC2 pre- explosion image F606W Gemini gri ( s), 0.56” images

8 Detection of progenitor HST ACS - ToO (Cycles 10-15) Smartt et al. (2003), Van Dyk et al. (2003): possible progenitors from ground based astrometry calibration Star A: Differential astrometry:  r = 13 ± 33 mas

9 Magnitudes and colours of progenitor V=25.8 ± 0.15 V–I=2.5 ± 0.2 d=9.1 ± 1.9 kpc ; E(B– V)=0.14 ± 0.13 K5-M3Ib supergiant (Elias et al. 1985) STARS stellar evolutionary tracks: M = 8 -2 M  +4 Smartt et al. 2004, Science

10 SN2005cs in M51 SN2005cs – discovered Hubble Heritage Team - deep mosaic BVI+H  with ACS (Jan. 2005) F814W/F555W 1360s WFPC2 U+R band (Jul. 1999) Also deep NIR images: NICMOS (F110W+F160W; see Li et al. 2006) Gemini NIRI (JHK) s  deep UBVRIJHK images

11 Detection of progenitor HST ToO : ACS post-explosion (F555W) Star detected in I-band only (J. Maund PhD thesis) I=23.3±0.05, and limiting V-band mag is V 5  > 25 Not detected in any of the NIR bands; K>20.7 Maund et al. (2005), Li et al. (2006)

12 Other examples: no detection SN1999gi in NGC3184, HST U+V pre-explosion D=11Mpc (Leonard et al. 2002) M  12 M  SN2001du in NGC1365 HST UVI pre-explosion D=17Mpc (Cepheid Key P.) M  15 M  Smartt et al Smartt et al. 2002

13 Summary of II-P progenitors SNTypeMassZRef 2006bcII-P<15~Z  2005csII-P9 +3/-2~Z  2004etII-P 15  2 ~1-0.5Z  Li et al djII-P 15  5 ~Z  Maiz-Apellaniz et al. 2004, Wang et al. 2005, amII-P8-10~Z  2004dgII-P<12~Z  2004AII-P 10  2 ~0.5Z  2003gdII-P8 +4/-2~Z  2002hhII-P<15~Z  2001duII-P<15~Z  1999evII-P 16  Z  1999emII-P<151-2 Z  1999giII-P<121-2 Z  1999brII-P<12~Z  1999anII-P<20~2 Z  Rest from Crockett et al. 2006, Maund & Smartt 2005, Maund et al. 2005, Hendry et al. 2006, Smartt et al. 2004, 2003, 2002, 2001

14 Heger et al. (2000) - now can place observational constraints Observed II-P 93J 87A 80K Observed Ib/c

15 STARS stellar evolutionary tracks (Eldridge & Tout 2004) Eldridge, Smartt (in prep) - probability without mass cut ~5%

16 Late time tail powered by radioactive 56 Ni 56 Ni explosively created from Si burning after core- collapse Direct probe of the explosion How Is it related to progenitor mass ? UVOIR Light Curves and 56 Ni Mass

17 Black-hole forming SNe ? Zampieri et al., Nomoto et al - low luminosity SNe form black-holes No evidence so far of the branching at high luminosity Detailed comparison with models now possible

18 Constraints on a Type Ic SN2004gt - type Ic Gamma-ray bursts coincident with Ic supernovae

19 Restricted region in the HRD We would have detected massive evolved stars Either a star of M  or More likely a lower mass object in a binary Maund, Smartt, Schwiezer (2005) Gal-Yam et al. (2005) Four other Ib/c SNe, all with similar luminosity limits Type Ia SNe - 7 events, no object/cluster.

20 Conclusions SN II-P: most common type, red supergiant progenitors (~M0Ib 8-12M  ) Detections and limits on 15 II-P SNe imply they only come from RSG stars with M ZAMS <15M  No evidence for BH forming Sne Within 3 years project  ~30 progenitors (HST SNAP + VLT/Gemini NIR purpose built archive) Optical/NIR monitoring of SNe gives 56 Ni - probe of explosion Direct constraints on all core-collapse SNe types

21 Nearby core-collapse SNe: discovery rates No. of SN per year in galaxies less than V rad km/s N sn (V rad <1500) = 8.7 yr -1  H 0 = 75 kms -1 Mpc -1

22 Radio and X-ray luminosity of II-P Chevalier et al. (2005) Radio and X-ray L P consistent with direct mass estimates

23 M31 RSG variable Young, Smartt et al. in prep. 4 years monitoring of M31 (microlensing) Largest variation ±0.5 m ±0.2 dex in logL/L M-type supergiant, M~20M , logL~5.2 dex

24 Magnitudes and colours of progenitor d=8.4 ± 1 kpc; E(B – V)=0.14 ± 0.02 Colours of K5-M4Ib supergiant scaled to I=23.3 Bluer than early K- type and it would be detected in V and R. Wavelength Magnitude

25 Dust enshrouded red supergiants ? Could progenitors be dusty red supergiants, some of higher luminosity ? SNe are clearly not reddened But could be destroyed in explosion (e.g. Meikle & Graham 1986)? Our deep K-band image rules this out (K>20.7) If visual extinction A V ~5 K-band limit implies M K >-9.5 or log L/L  < 4.6 Hence M < 12M  Gemini NIRI K-band 0.5” 50 Galaxies (<10Mpc) surveyed with VLT/Gemini/UKIRT. Deep JHK images for future SNe

26 ACS images SN1993J: U 330 = Faint companions within 0.35” Contribution to SN of <20% Why is SN1993J so bright in UV ? Deep, near-UV Keck spectrum with LRIS-B

27 Evolutionary model ZAMS = 15 and 14M  stars 5.8 year period High mass loss from progenitor to companion ~1000 yrs pre-explosion (4x10 -2 M  /yr) SN1987A like event (in years time) ? Maund, Smartt, Kudritzki, Podsiadlowski, Gilmore 2004, Nat.