The Carnegie Supernova Project (CSP): Latest Results

SN2006X

Outline of Talk

• What is the CSP?

• General statistics

• Low-z SNe Ia

• First BVugriYJHK data set

• High-z SNe Ia

• i band Hubble Diagram to z ~ 0.7

• Type Ib/Ic SNe

• SN 2007Y

• Making the Data Available

SN2008aw

People

Other collaborators

Alex Filippenko (UC Berkeley)Weidong Li (UC Berkeley)

Ray Carlberg (Univ. Toronto)Josh Frieman (Chicago/Fermi Lab.)

Darren Depoy (Ohio St.)Jose Luis Prieto (Ohio St.)

OCIW

Wendy Freedman P.I. High-zEric Persson

Barry Madore Chris Burns (postdoc)

Pamela Wyatt (OCIW/IPAC)David Murphy

Texas A&M

Nick SuntzeffKevin Krisciunas

Lifan Wang

Chile

Mark Phillips (OCIW/LCO) P.I. Low-zMario Hamuy (U. Chile) Original P.I. Low-z

Max Stritzinger (OCIW/LCO, postdoc)Gastón Folatelli (U. Chile, postdoc)

Miguel Roth (OCIW/LCO)Nidia Morrell (OCIW/LCO)

Alejandro Clocchiatti (PUC)Wojtek Krzeminski (OCIW/LCO retired)

Carlos Contreras (former research assistant)

Sergio Gonzalez (research assistant)Luis Boldt (research assistant)

Francisco Salgado (research assistant)

Chilean StudentsInvolved with the CSP

Felipe Olivares (U. Chile)Alejandra Molina (U. Chile)

Luis Boldt (PUC)Felipe Murgas (U. Chile)

María José Maureira (U. Chile)Fernando Becerra (U. Chile)

andCarlos Contreras (PUC)

• Obtain high-quality, gap-free BVugriYJHK light curves and optical spectrophotometry of:

• ≥100 nearby (z<0.07) Type Ia supernovae

• ≥100 nearby (z<0.05) Type II supernovae

• ≥20 nearby (z<0.05) Type Ibc supernovae

• Refine methods for obtaining distances to Type Ia and Type II supernovae

• Provide a new fundamental reference for observations of high-z supernovae

• Gain insight into the progenitors and explosion mechanisms of supernovae

Low-z CSP Goals

Telescopes/Instruments

Optical (u’BVg’r’i’) Photometry: Las Campanas Swope 1-m telescope + CCD

Infrared (YJsHKs) 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) High-z Optical (0.32-1.0 μm) Spectroscopy: Las Campanas du Pont 2.5-m telescope + WFCCD (or Modspec, or B&C) Magellan Clay 6.5-m telescope + LDSS-3 (or IMACS) CTIO 1.5-m telescope + Cassegrain Spectrograph (service mode) ESO NTT+EMMI

Swope 1-m Du Pont 2.5-m Magellan 6.5-m

Low-z workhorse

Observing Campaigns

One 9-month campaign per year from September-May

• ~230 nights per campaign at Swope 1-m

• ~80 nights per campaign at duPont 2.5-m

• A few nights of Magellan time

• A total of five campaigns will be carried out

• The final campaign will end in this coming May!

Filters

BV + ugri + YJHKs

Sources for Supernovae

LOSS + many others

And, beginning in 2008, CHASE!

Statistics After 4 Campaigns

Through 4 campaigns, observations have been obtained of 286 SNe. Of these, a full set of follow-up observations has been obtained for 194 (67%)

Statistics (cont.)

• Through the first 4 campaigns, a total of 1,190 spectra of 211 SNe have been obtained

• Classifications reported to IAUC for 101 SNe

• Most spectra obtained at Las Campanas Observatory

• Additional spectra obtained with ESO NTT, and in collaboration with Darren Depoy & Jose Luis Prieto

• For the SNe selected for follow-up during the first three campaigns, average sampling frequency was ~1 spectrum per 9-10 days

• This has been improved during the last two campaigns through a collaboration with the Millennium Center for Supernova Studies (Mario Hamuy, PI)

SNe Ia Observed in Campaigns 1 & 2

Low-z SNe Ia: Redshift Range by Type

• ~75% of SNe Ia lie in Hubble flow (z > 0.015)

• Median redshift of SNe II is less than that of SNe Ia since SNe II are intrinsically less luminous; nevertheless, more than half of SNe II lie in Hubble Flow

• SNe Ib/Ic are much less common, and also relatively nearby due to their low luminosities

Low-z SNe Ia: Optical Light Curves

m15(B)

0.90

1.83

Low-z SNe Ia: Optical Light Curves

Low-z SNe Ia: Range of Decline Rates

Low-z SNe Ia: Near-Infrared Photometry

• Near-IR (NIR) photometry is a key component of the Low-z CSP

• Goal is to obtain NIR observations of most SNe at a cadence of one set of YJH observations per 3-5 days

• This goal was not achieved for the first CSP campaign (due to delays in completing the Retrocam imager for the Swope 1 m telescope)

• The 2nd, 3rd, and 4th campaigns have achieved this goal, resulting in some of the best NIR light curves of SNe Ia, SNe Ib/c, and SNe II ever obtained

• NIR light curves will be obtained for > 80% of SNe

Low-z SNe Ia: Light Curve Templates

CSP i’ light curvesi’ templates

Low-z SNe Ia: Light Curve Shapes

• The secondary maximum is observed from the r to the K bands, and is strongest in the Y band (1.03 µm)

• The time between the primary and secondary maxima is typically ~30 days; the secondary maxima occurs earlier for faster-declining events

Commercial BreakFor many more results on the CSP sample of Low-z SNe, don’t miss Gaston Folatelli’s talk this afternoon!

From: Astier et al. 2006

Measuring Dark Energy with SNe Ia:Current State of the Art

From: Wood-Vasey et al. 2007

SN Legacy Survey ESSENCE

From: Kowalski et al. 2008

Current State of the Art (cont.)Limits on w and ΩM Limits on Ω and ΩM

Ω = 0.713 ± 0.028 (stat) ± 0.038 (sys)

w = -0.969 ± 0.061 (stat) ± 0.065 (sys)

CSP High-z SNe Ia

• At the redshift range (0.3 < z < 1.0) observed by SNLS and ESSENCE, the light curves correspond to the UBV bands in the rest system

• To minimize errors due to reddening, the Carnegie Supernova Project (CSP) has been working to produce the first rest system i band Hubble diagram over the redshift range (0.01 < z < 0.7)This is a completely new and independent

data set!

z = 0.35 z = 0.63

CSP High-z SNe Ia:Sources of Supernovae

SN3241Discovered by SDSSz = 0.25

D149wcc4-11Discovered by ESSENCEz = 0.30

05D2btDiscovered by SNLSz = 0.679

CSP High-z SNe Ia: Host Galaxy Subtractions

z = 0.25Y filter

z = 0.30Y filter

z = 0.679J filter

CSP High-z SNe Ia: Light Curves

The First Rest System i Band Hubble Diagram to z

~ 0.7

Current State of the Art (cont.)Limits on w and ΩM Limits on Ω and ΩM

Premliminary results:

Ω = 0.76 ± 0.08 (stat) ± 0.08 (sys)

w = -1.05 ± 0.08 (stat) ± 0.08 (sys)

SN 2007Y: A Type Ic SN

• The CSP observes ALL nearby SNe caught at or before maximum

• Max Stritzinger has been working on CSP data obtained of SN 2007Y, a type Ib/c SN• This SN was also observed with Swift in the UV and X-Rays

• These data are among the best ever obtained for a SN of this type

SN 2007Y: Light Curves

CSP + Swift observations

Late-time photometry obtained with ESO VLT

SN 2007Y: Bolometric Light Curve

SN 2007Y: Optical Spectra

Comparison with SN 2005bf

CSP Spectra of SN 2007Y

SN 2007Y: Nebular Phase Spectroscopy

IIb

Ib

Ib

Spectrum obtained with Magellan 6.5 m Clay Telescope

SN 2007Y: Conclusions• Ejected mass of 56Ni ~ 0.6

solar masses (bolometric light curve + nebular phase spectra)

• Ejected oxygen mass ~ 0.2 solar masses (nebular phase spectra)

• Total ejected mass below 4500 km s-1 was 0.42 solar masses (nebular phase spectra)

• ZAMS mass of progenitor ~13 solar masses (nebular phase spectra)

• Explosion energy ~ 1050 erg (light curves + optical spectra)SN 2007Y among the least energetic SN Ib studied to

date

Making the Data Available

• In early-February, we expect to submit three papers:

• A first data paper presenting optical and NIR photometry for 35 Low-z SNe Ia

• An accompanying analysis paper of these data, and

• A third paper presenting rest system i band light curves of 35 High-z SNe Ia

• Next week, a paper on the type Ib SN 2007Y will also be submitted

• Data will be made available immediately thereafter to those who are interested via a special web site

• We will also work with IPAC to make the data permanently accessible via NED

Refereed Publications Including CSP Data

1) Hamuy, M., et al. 2006, PASP,118, 839, “The Carnegie Supernova Project: The Low-Redshift Survey”

2) Folatelli, G., et al. 2006, ApJ, 641, 1039, “SN 2005bf: A Possible Transition Event between Type Ib/c Supernovae and Gamma-Ray Bursts”

3) Phillips, M. M., et al. 2007, PASP, 119, 360, “The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?”

4) Hsiao, E. Y., et al. 2007, ApJ, 663, 1187, “K-corrections and Spectral Templates of Type Ia Supernovae”

5) Taubenberger, S., et al. 2008, MNRAS, 385, 75, “The Underluminous Type Ia Supernova 2005bl and the Class of Objects Similar to SN 1991bg”

Published:

To be submitted soon:1) Contreras, C., et al. 2009, “The Carnegie Supernova Project: First Photometry Data

Release of Type Ia Supernovae”

2) Folatelli, G., et al. 2009, “The Carnegie Supernova Project: Analysis of the First Sample of Low-Redshift Type Ia Supernovae”

3) Freedman, W. L., et al. 2009, “The Carnegie Supernova Project: First Near-Infrared Hubble Diagram to z ~ 0.7”

4) Stritzinger, M., et al. 2009, “The He-Rich Core-Collapse Supernova 2007Y: Observations from X-Ray to Radio Wavelengths”