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					High-redshift Supernovae with 30m-
        Class Telescopes
             Mark Sullivan
           University of Toronto
     Supernovae as Astrophysical Probes
                                                Baryonic
                                                  Matter
Dark Energy:                           Dark Matter
                                                   5%

                                           22%


                                                            Dark
                                                           Energy
                                                            73%

Measuring w(a) has become a key goal for cosmology
   Type Ia Supernovae – Thermonuclear explosions of
    Chandrasekhar mass C-O white dwarfs
   Currently used to z~1.5

Type IIP Supernovae as standard candles
   Method demonstrated to z=0.3

SN rates, environments and progenitors

Core-collapse SNe over 2<z<6 – see talk by Jeff Cooke
Type Ia Supernovae
 Imaging                        Spectroscopy

•SN Discoveries
                                • Redshifts/Types
                                 Distances from cosmological model

                                • SN Chemistry
•SN Distances (Std. Candle)     • SN Physics
•SN Light-curve shapes




                  Dark Energy
           Making a
           standard
            candle

M B = M BO + " ( s # 1) # !c



                Provides
                distances
               accurate to
                   7%
                          Current SNe Ia
                         Hubble Diagrams

                             “Third year” SNLS
                              Hubble Diagram
                               (preliminary)

                        250 high-z + 40 low-z
Preliminary


                        Best-fit for SNLS+flatness




              ΩM=0.3, Ωλ=0


              ΩM=1.0, Ωλ=0

                             Sullivan et al. 2007
             Timeline for future SN surveys
    (SNe Ia only)

Time          z<0.1           0.1<z<1                 z>1
                             SNLS ~500
End     KAIT/CfA/CSP ~300                    HST/GOODS ~20
                            Essence ~200
2008     SN Factory ~100                     HST Clusters ~15
                             SDSS ~250
                               DES
2009-      SkyMapper                            HST/WFC3
                            PANSTARRS
2013
2014          PTF                          Possible 8m searches?
                              SNLS-2?
                                                 JDEM
>2015           ?           LSST ~ nx104         JWST
                                                TMT/ELTs


             Baseline SN Ia numbers by mid-2010s:
           500 z<0.08, 300 0.08-0.25, 1000 0.25-1.1
                                                  Rest-frame B/V-
How to find z>>1 Supernovae?                     band  Y,J,H,K to
                                                        z=4

 8m-class z/Y or J-band searches with near-IR imagers?
     (might push to z=1.2-1.4)


 A search with TMT appears inefficient
     IRIS: 15”x15” imaging (but parallel imaging??); WIRC 30”
     FoV  <0.2 SNe Ia per field
     But, very very deep: K~30 3σ in 3 hours – detections z>5?
                                                  Rest-frame B/V-
How to find z>>1 Supernovae?                     band  Y,J,H,K to
                                                        z=4
  Search with JWST?
      NIRCam: 2.1’x2.1’: 3 hours K=28.9 (AB) 10σ
      z=4 SN Ia has K=26.8 @ peak – well matched to JWST
      Small area; maybe 1-3 SNe Ia & 5-10 CC SNe per field
      Need to monitor 25-50 fields for ~5 years to get 150-250 SNe
      As with HST/GOODS, could be “piggy-backed” onto a large
       survey program

  Search with JDEM?
      Wider area (1o) than JWST so many more SNe
      Select z>1.5 SNe, or lower-z SNe for detailed spec. studies
      Good source of SNe IIP
      May require some TMT photometric follow-up
         How to study high-redshift SNe?
Spectroscopy very hard at z>1 with current instruments
Current spectroscopy at z>1

                               2 hours in good
                              seeing on an 8m
                                with nod-and-
                                   shuffle!
                              (and a very faint
                                host galaxy)



                                Spectra are
                              useful for little
                              else other than
                              confirmation of
                                SN type and
                                  redshift
                               determination
         Benefit of AO: Host galaxy studies
               SNe are point sources buried in
                possibly bright host galaxies




Images: I. Hook PSFs from ESO (Le Louarn et al)
            Benefit of AO: Host galaxy studies
              TMT Example: IRIS IFU of SN+host galaxy
              Host contamination on SN spectrum small
Metallicity, star-formation, chemistry of host galaxy can be studied
                             on kpc scales
               No AO                                 NFIRAOS AO




   Images: I. Hook PSFs from ESO (Le Louarn et al)       H-band, z=1.65
             Spectroscopic performance
            Peak magnitude      Spectroscopic exposure time (hrs) –
Redshift
                 (AB)              assumes NFIRAOS, S/N=5

                                        30m                 42m

    1.7         J =25.3                 0.16                0.07

    2.8         H=26.1                  1.7                  0.9

    4.0         K=26.8                  6.1                  3.2

                                                     Courtesy: I. Hook

JWST feeding TMT (possibly) hundreds of SNe
JDEM feeding TMT (possibly) thousands of z>1.5 SNe
IRIS IFU gets simultaneous galaxy information
    Star-formation, metallicity, age
(What will be the spectroscopic capabilities of any JDEM?)
Will Dark Energy be an interesting problem for TMT?


                                        SNe only




SNe only




    BAO




 Only SNe + flat Universe assumed. No prior on ΩM
                 500 from 0.1<z<1.1 + 0.1<z<1.1
     500 low-z + 1500low-z + 1500 from 250 JWST/TMT 1<z<3
      Limitations of z>2 for dark energy
z>2: Matter dominated, dark energy has small effect




       Const. w                                  SUGRA


                     Aldering et al. 2006; see also Riess & Livio (2007)
           Detailed Spectroscopic Programs
   Over 0<z<3, studying SNe Ia probes a wide range of
   progenitor age and metallicity
      Could provide the most robust test of evolution in SNe Ia


 UV most susceptible to progenitor composition.

       At high-z, rest-frame UV is redshifted to optical bandpasses
       Detailed Spectroscopic Studies – UV

                                                                    Consensus:
                                                                   UV probes line
                                                                   blanketing by
                                                                      metals
                                                                      Early UV
                                                                       probes
                                                                     progenitor
                                                                     metallicity


                 Effect of varying
                   metallicity in
                 unburnt layers of
                      SNe Ia




Lentz et al. (2000) + others         UV redshifted into optical/near-IR bandpass
Maximum light




                                        Example from
                                         Keck+SNLS
                                       detailed studies
                                          program




                        Detailed spectra studies
                      currently limited to z=0.6-0.7
                         TMT can push to z=2
  Ellis et al. 2007
           Detailed Spectroscopic Programs
   Over 0<z<3, studying SNe Ia probes a wide range of
   progenitor age and metallicity
      Could provide the most robust test of evolution in SNe Ia


 UV most susceptible to progenitor composition.

       At high-z, rest-frame UV is redshifted to optical bandpasses


 Optical region
       Luminosity and kinetic energy tracers in optical spectra
                            EW SiII
EW CaII




            CaII velocity




  EW MgII
                      Interpretation: at
                       Chandra mass,
                       zero sum game,
                       more Si means
                       more IMEs, less
                         Fe-peak, but
                      temperature also
                         plays a role




Bronder et al. 2007
                                              Bronder et al. 2007 – Astier et al.
                                              (2006) SNe Ia with Gemini spectra
modulus




           • Uncorrected                                  • Uncorrected
distance




                                   modulus
                                   distance
           dispersion 0.37 mag                            dispersion 0.37 mag
           • EW SiII correction                           • s and c correction
           dispersion 0.26 mag                            dispersion 0.23 mag

             redshift                                      redshift
Residual




                                  Residual




              redshift                                     redshift
           Detailed Spectroscopic Programs
   Over 0<z<3, studying SNe Ia probes a wide range of
   progenitor age and metallicity
      Could provide the most robust test of evolution in SNe Ia


 UV most susceptible to progenitor composition.

       At high-z, rest-frame UV is redshifted to optical bandpasses


 Optical region
       Luminosity and kinetic energy tracers in optical spectra


 IFU allows detailed studies of SN environment + host
       Metallicity from galaxy lines
       Star-formation, ages of stellar populations
             SNLS: SN rate as a function of sSFR
   SN Ia hosts
classified by star-
formation activity


Per unit stellar mass,
 SNe are at least an
 order of magnitude
  more common in
more vigorously star-
  forming galaxies




   SNLS “passive”
      galaxies
                                                                   SN Ia
                                                                 volumetric
                                                                    rates


                                           Here there be
                                             dragons




Evolution from “two-component” SN Ia models e.g.
              TMT will provide the first census of SNe in the z>1.5
   Mannucci et al. 2005,2006; Scannapieco &
                                    Universe
        Bildsten 2005; Sullivan et al. 2006
Type IIP Supernovae
Type IIP Supernovae
             • Hydrogren in spectrum
             • 90 day plateau in lightcurve
             ~5 times more common compared
              to SNe Ia (per unit volume)
             Physics of spectra/atmopsheres
              dominted by H, in principle
              cleaner than SNe Ia


             BUT ~1.5mag fainter



                       I-band luminosity @ day
                      50 proportional to velocity
                      I-band less dust sensitive
                         that B-band (SNe Ia)
                       +V-I colour correction for
                               extinction
     SNe IIP as standard
           candles

     I-band luminosity @ day 50
        proportional to velocity
                                                After
     In more luminous SNe, hydrogen
 recombination front maintained at higher
 velocity, pushing photosphere farther out.
        For SNe IIP, correlations are
  expected/observed between VFeII (which
 track the electron-scattering photosphere)     Before
               and luminosity.



                                                  Hamuy et al.

  [Also: Expanding Photosphere method (EPM)
Spectral Expanding Atmosphere Method (SEAM) ]
 Keck/LRIS Obs. of
  SNLS SNe IIP


  These are incredibly
demanding observations
 (2-3hr/spectrum) to get
enough S/N in the weak
        FeII lines.


The technique is currently
   restricted to z=0.3


   Nugent et al. 2006
                                                       SN IIP Hubble
                                                         Diagram
                                                       " = 0.26mag.
                                                        # 2 ( pdof ) = 1.4

                                                     Includes uncertainties from:

                                                      Extinction
                                         !            Explosion date
                                                      Photometry
                                                      Velocity

Many local SN surveys will
improve the low-z sample
                             Hundreds of SNe IIP will be in reach of TMT to z=1
                                  Independent Hubble Diagram to SNe Ia
                         Summary
TMT/JWST/JDEM synergy opens new windows on SNe at z>1
   JWST/JDEM discoveries, TMT follow-up

SNe Ia at z>1 dramatically improve cosmological constraints

Detailed cross-checks on metallicities of SNe Ia at z=0-3

TMT will provide the best measurement of all SN rates at high
(z>1.5) redshift, allowing a detailed analysis of SN progenitors

TMT/JWST/JDEM can construct an independent SNIIP-based
Hubble Diagram to z~1

				
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posted:6/28/2011
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