Download Red Supergiants as the Progenitors of Type IIP Supernova

The Red Supergiant Progenitors of
Core-collapse Supernovae
Justyn R. Maund
Stellar Populations Workshop
IAG-USP 1st December 2015
Astronomy and Astrophysics at
Sheffield
8 Academic staff
5 Postdocs
13 PhD students
Massive Stars
Supernovae
Brown Dwarfs
Instrumentation
Star Formation
Active Galactic Nuclei
Time Domain
Massive Stars
t ~ Myrs
Explosion Mechanism
t ~ secs
4
Hammer et al.
F IG . 2.— Surfaces of the radially outermost locations with constant mass fractions of ∼ 3% for carbon (green), and oxygen (red), and of ∼ 7% for nickel
(blue). The upper two panels show the directional asymmetries from two different viewing directions at 350 s after core bounce when the metal clumps begin to
enter the helium layer of the star. The lower two panels display the hydrodynamic instabilities at about 9000 s shortly after the supernova shock has broken out of
the stellar surface. The side length of the upper panels is about 5 × 1011 cm, of the lower panels 7.5 × 1012 cm.
act as seeds of secondary Rayleigh-Taylor instabilities at the
composition interfaces of the exploding star. At about 100 s
dense Rayleigh-Taylor fingers containing the metals (C, O, Si,
iron-group elements) have grown out of a compressed shell of
matter left behind by the shock passing through the Si/O and
(C+O)/He interfaces. These fingers grow quickly in length
and while extending into the helium shell, fragment into ballistically moving clumps and filaments that propagate faster
than the expansion of their environment.
While for a 2D model with explosion energy around
1.8× 1051 erg the Si and Ni containing structures still move
with nearly 4000 km s-1 (oxygen has velocities up to even
5000 km s-1) at 300 s, a strong deceleration occurs when the
metal clumps enter the relatively dense He-shell that forms
after the shock passage through the He/H interface. At t
10, 000 s the metal carrying clumps have dissipated their excess kinetic energy and propagate with the same speed as the
helium material in their surroundings. In the presence of a
hydrogen envelope and the corresponding deceleration of the
shock as it propagates through the inner regions of the hydrogen layer (in which case the helium “wall” below the He/H
interface builds up), Kifonidis et al. (2003) could not observe
any metal clumps that achieve to penetrate into the hydrogen envelope, in contrast to what was observed in the case of
SN 1987A.
The 2D calculations performed in the course of the present
work confirm these findings (when the velocities are appropriately rescaled with Eexp to account for the lower explosion energies of Eexp 1051 erg considered here compared to
roughly twice this value employed by Kifonidis et al. (2003).
The evolution as well as the final results for the mass distributions of different chemical elements in velocity space and
mass space are in good quantitative agreement with the mod-
SN evolution
t ~ kyrs
WR stars
RSGs
Single star tracks - Cambridge STARS code, Eldridge & Tout (2004)
Direct detection in pre-explosion images
Finding progenitors
Ingredient #1:
Fortuitous Pre-explosion
Images
Ingredient #2:
High-Resolution Postexplosion Images
Possible
with the
advent of
public progenitor position to with a ~few 10s
Differential
astrometry
– achieve
telescope
archives.
milliarcseconds
Resolve
individual
out to 10Mpc
Sources:
Hubblestars
or imaging
or ground-based AO image
(ground based) or 25Mpc (Hubble)
2003gd
SNSN2003gd
Van Dyk et al., 2003
Smartt, Maund et al., 2004, Science
Pre-explosion WFPC2 F606W and Gemini i’ -> V-I colour
Assume reddening is same as for nearby stars (main sequence)
Determine star’s properties from just a handful of broad-band
photometric points – in case of non-detection only upper limits
Disappearance = confirmation
SN 2003gd ~8M
Maund & Smartt, 2009, Science
Gemini GMOS i’ image
Late-time observations ~5 years post-explosion
Compare observed
luminosity with the final
luminosities predicted for
stars with a given initial
mass
If no detection, use
detection limits to place
upper luminosity limit
Take mass estimate to be
between onset of He
burning and the model end
point
End of model
End of core-He burning
Smartt et al. 2009 : initial
masses are quoted with
Gaussian uncertainties
Maund et al., 2014a,b,
2015a,b: quote initial
mass as combination of
pdfs (luminosity
convolved with mass
range)
Ruling out S-AGB progenitors
Low luminosity SNe don’t necessarily have to come from ECSNe
Deep NIR imaging limits on the progenitor of SN 2005cs,
exclude
S-AGB end points (through
comparison with
MARCS
Mass
PDF
HRD
Teff vs E(B-V)
models)
Maund et al., 2014a
How much dust affects
progenitors?
Fit the SED (optical and IR) of SN 2012aw, assuming RV = 3.1  large range in
T and E(B-V) (degeneracy) – could this be a low mass progenitor or high mass
but extinguished
No evidence of high levels of AV in SN spectra – could dust be CSM
Fraser et al, 2012; Van Dyk et al, 2012
SN 2008bk – the best progenitor detection*
Progenitor detected in 8
photometric bands (g’r’i’IYJHK)
2 upper limits(BV)
Maund et al., 2013
Mattila et al., 2008 (IJHK)
Van Dyk et al., 2012 (g’r’i’JHK)
Confirmed to have disappeared
(Mattila et al., 2011)
Determine parameters with
respect to MARCS synthetic
spectra
*Since SN 1987A
SN 2008bk
Highly reddened, higher temperature(!!!) progenitor than normally expect – most
precise mass derived for a progenitor so far, with systematics understood.
Late-time observations taken under excellent seeing and photometric conditions
(independent calibration)
500R
Davies et al. (2013) – Xshooter
observations of SMC and LMC
RSGs
1100R
Dessart et al. (2013) – smaller
progenitor radii required to match
early UV light curve for Type IIP
SNe
Results from new progenitor analysis simultaneously match observed properties of
RSGs and requirements for Type IIP SNe – suggest stellar evolution models need a
tweak
SED models give us T bolometric correction – the SED is what we care about
(ATLAS9 and MARCS models give similar results). The progenitor of SN 2008bk
has the colours of a K-supergiant (have we previously made wrong assumptions for
JWST
The unknown amount of CSM dust
and the temperature scale for RSG
progenitors are a big unknown
Move further into the IR !!!
JWST NIRCAM observations can
rival HST spatial resolution
F444W (4μm) filter pretty much insensitive to dust and the bolometric correction
changes only marginally over the expected temperature range for RSGs (30005000K)
Expect RSG progenitors in the range log(L/L)=4.0 – 5.5
1000s exposure with JWST in F444W will give a 5σ detection for the faintest
RSG that can explode as a SN out to 25Mpc
The Type IIb SN 1993J
Second closest SN in modern era (M81)
Second ever progenitor ID
Simultaneously blue + red SED
K-supergiant not M-supergiant progenitor
Peculiar double peaked light curve
Changed from H-rich Type II to Hpoor Type Ib
Aldering et al., 1994, AJ, 107, 662
A binary progenitor system
Late-time spectroscopy
revealed B-supergiant
companion in fading
remnant of the Type IIb
SN1993J – hence
confirming the binary
progenitor scenario, and
peculiar observed colors of
the progenitor in preexplosion images.
1 Night with Keck, just get
absorption lines from a star
with mB ~22 at 3Mpc
Maund et al., 2004, Nature, 427, 129
Van Dyk et al., 2002, PASP
Spectroscopy with the E-ELT
• With E-ELT+MOSAIC
can conduct
spectroscopy of stars out
to ~35Mpc
• Instead of fortuitous preexplosion images, could
we have a high-S/N,
high-resolution spectrum
of the progenitor of a
SC5: Resolved stellar populations
beyond
future
SN? the Local