Carnegie Supernova Project: Detailed Observations of Supernovae

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1 Carnegie Supernova Project: Detailed Observations of Supernovae Maximilian Stritzinger Oskar Klein Centre Stockholm University Burro Las Campanas via FB

2 Supernova! Anglo-Australian Telescope

3 Working Taxonomy of the Supernovae Zoo Super Chand.: 2003gf, 2006gz, 2007if, 2009dc Low-luminosity: 2002cx- to 2008ha-like Broad-line objects associated w/ and w/o GRB or X-ray fashes

4 Distribution of MB and SEDs

5 CSP Observational Goals 1. Obtain precision ugribvyjh light curves and spectrophotometry of 100 SNe Ia (z 0.07) 100 SNe II (z 0.05) 20 SNe Ibc (z 0.05) 2. YJ-band light curves of 100 SNe Ia at cosmological distances (0.1 < z < 0.7)

6 CSP Science Goals 1. Gain insight into the progenitors and explosion mechanisms What do SN come from and how do they explode? 2. Refne methods for determining distances to Type Ia (test for variable ω requires 1% accuracy in distance) and Type II SNe (Ho) 3. Provide a new fundamental reference for observations of high-z Type Ia SNe 4. Characterize dark energy by producing a rest-frame i-band Hubble diagram of low- and high-z SNe Ia where reddening and light curve corrections are small (reduced systematics)

7 CSP Telescopes/Instruments Optical (ugribv) Photometry: Las Campanas Swope 1 m telescope + CCD Some 30 to 40 nights per month --> 1500 nights of data... Near-Infrared (YJHKs) Photometry: Las Campanas Swope 1-m telescope + RetroCam (YJH) Las Campanas du Pont 2.5-m telescope + WIRC (YJHK) Las Campanas Baade 6.5-m telescope + PANIC (YJHK) Optical Spectroscopy: du Pont 2.5-m telescope +WFCCD or B&C Magellan Baade & Clay 6.5-m telescopes +LDSS-3 or +IMACS CTIO 1.5-m telescope + Cassegrain Spectrograph ESO NTT +EMMI or EFOSC2 Gemini-South +GMOS NIR Spectroscopy: VLT +ISSAC, NTT +SOFI, SOAR +OSIRIS

8 Las Campanas as a site Color terms Extinction Coeffcients 2 out of every 3 nights were photometric!!! Contreras et al. 2010

9 Striving towards precision SN cosmology Know your photometric system --> S-corrections Optical Near-infrared Stritzinger et al. 2011a

10 CSP: Low red-shift fnal tally Ia II Ibc Total Actual Expected

11 Blood, Sweat and Tears... - Observations: several months per object (opt. & NIR) - Data reduction - Calibration of Local Sequences 3x: opt. & NIR - Galaxy Template Observations w/ good seeing - Galaxy Template Subtraction - Final Photometry in the natural system

12 Examples of Type Ia Light Curves First release: 35 objects with 25 having near-ir Contreras et al. 2010

13 Light Curve ftting with SNooPy: SuperNova in object-oriented Python Burns et al. 2011

14 SN Ia Color Excesses Lira Relation for Suspected Low-Reddening SNe Ia Implied Instrinsic Color vs Decline Rate Relations Folatelli et al. 2010

15 SN Ia Color Excesses How can this be? There is a component of one or the other of these color excesses which is not due to dust? Time varying extinction? appears to be an intrinsic dispersion in the colors of SNe Ia which is correlated with luminosity but independent of the decline rate. Viewing angle effects on the peak colors of SN (Maeda et al.)

16 The Reddening Law Color excess ratios are a function of Rv. SNe w/o Signifcant Reddening --> Rv 3 The Wang/Goodbar dust scattering model looks promising to explain the low Rv values of highly reddened SNe Ia Folatelli et al. 2010

17 The Reddening Law Here we assume either direct distance or Huble fow distance and then treated Rv as a free parameter to minimize B = MB + b [Δm15(B)-1.1] + RB E(B-V) + μ, A value of RV ~ 1.5 is obtained, even for low-reddening events

18 SNe Ia as Precision Standard Candles Filter σ(mag) u 0.13 g 0.14 r 0.13 i 0.14 B 0.14 V 0.14 Y 0.15 J 0.12 H 0.16 z 0.08 Combining Hubble diagrams in different bands does not yield a signifcant improvement in the observed dispersion

19 SNe Ia as Precision Standard Candles This is b/c the residuals in each color are highly correlated, presumably due to peculiar velocities The implication is that we are actually measuring distances to a precision of 3% to 4% Folatelli et al. 2010

20 Testing the precision of SNe Ia Three normal and one sub-luminous SN Ia Stritzinger et al. 2010

21 SN Ia distance to Fornax A Distance moduli derived from the EBV and Tripp methods give the values that are mutually consistent with 4% 8%. Weighted means of the distance moduli for the 3 normal SNe for 3 methods agree to within 3% Stritzinger et al. 2010

22 Rest frame i-band Hubble diagram Independent determination of Dark Energy Freedman et al. 2009

23 2nd sample of Type Ia SNe consists of 50 objects w/ 45 having near-ir follow-up: Stay Tuned... Stritzinger et al. 2011a

24 CSP Spectroscopic Sample Folatelli et al. 2011

25 Stripped-Envelope Core Collapse Type Ib/c & Type IIb SNe What have we done thus far? SN 2005bf: Type Ib-pec SN 2007Y: Type Ib SN 2009bb: Type Ic-pec

26 A unique Type Ib: SN 2005bf Folatelli et al. 2006

27 A normal Type Ib: SN 2007Y Stritzinger et al. 2009

28 A peculiar Type Ic: SN 2009bb CSP & CHASE synergy Pignata et al. 2011

29 The CSP Type Ib/c, Type IIb Sample 25 out of 35 with NIR followup of > 5 epochs Most comprehensive homogeneous sample yet obtained!! Stritzinger et al., in prep.

30 Cooling Phase!!! Type Ib/c SN Light-curves

31 More Core-Collapse SNe favors: Type IIn Type IIn: several well-observed objects: SN2005ip, SN2005kj, SN2006aa, SN2006bo, SN2006jd, SN2008bm

32 The Type IIn SN 2006jd Also strong radio and X-ray emission Stritzinger et al. 2011b

33 More SNe Flavors: Type IIP & Cosmology SNe in the Hubble fow yield a dispersion of 0.2 mag (9% in distance) Hamuy & Pinto 2002

34 Type IIP Light Curves Expanded homogenous sample and near-ir observations will improve upon this method! More to come... Anderson et al., in prep.

35 Conclusions i. When reduced the Type Ia sample in hand will provide a fundamental reference for future cosmological studies, AND will serve as a rich source for the study of the physics of SNe Ia ii. The fact that low values of RV ( 1 2) are obtained when it is treated as a free parameter in minimizing the dispersion in the Hubble diagram is puzzling --> The implication is that there is an intrinsic dispersion in the colors of SNe Ia which is correlated with color, but is independent of the decline rate --> viewing angle for an off center explosion, see Maeda et al iii. Type Ib/c sample will allow for new methods to determine extinction and fnd relations between LC properties and spectrophotometry --> progenitors, single, binary? iv. Type IIP sample will be a major step forward for their use as distance indicators via the SC method v. Sample of low-luminosity (e.g. 2008ha-like) objects will shed light on their progenitors? vi. CSP2 has been funded for an additional 5 years to obtain SNe Ia in the smooth Hubble fow

36 Low Luminosity SNe SN2008ha-like objects: CSP observed SN2008ae, SN2008ha, SN2008ge (Foley et al. 2010), SN2009J, SN2010ae with MCSS What are the progenitors of these objects: WDs or CC SNe?

37 Other activities Super-Chand. Type Ia SNe 2007if & 2009dc, stalled --> DR2 = 50 objects! Near-IR K-corrections using Howie Marion's snapshot spectral sequence, Boldt et al. in prep. Bolometric light curves using Swift + CSP photometry, Boldt et al. in prep.

38 CSP2: Chilean & Euro time to obtain time-series w/ VLT +X-shooter & Gemini +GMOS +NIRI Temporal coverage is probably necessary for accurate K corrections

39 CSP2: Chilean & Euro time to obtain time-series w/ VLT +X-shooter & Gemini +GMOS +NIRI Temporal coverage is probably necessary for accurate K corrections