Supernova Rates: Today, and with the New HST

Dan Maoz

Riess et al. (2004, 2007) + Astier et al. (2006)

But supernova rates are also very interesting:

m=1,

m=0.3,

By measuring SN rates vs. redshift we can see cosmic metal enrichment in action!

+Figure out what is exploding in type-Ia’s

Supernovae: source of essentially all elements heavier than oxygen

Type Ia supernova:Accretion on, or merging of,C/O WD, up to ~MChandra .

Carbon ignition under degenerate conditions:Thermonuclear runaway

Yungelson & Livio (2000)

SN-Ia Rate (t)

t

SN-Ia “delay time distribution”

But: (Mannucci et al. 2005)

SN-Ia rate is proportional to star-formation rate!

Locally, ~1/2 SNe-Ia : “prompt” (~0.1 Gyr)

and

~1/2 SNe-Ia “tardy” (~5 Gyr)

SN delay time distribution (t)

Star-formation history (z)

*

SN rate (z)=

HST/ACS GOODS (~700 orbits) Riess et al. 2004, 2007, ~80 SNe, 46 SNe-Ia, 24 @ z>1

Peak in SN-Ia rate at z~0.8 implies 3 Gyr; inconsistent with expected dominance of “prompt” channel when SFR was 10X greater than today.

Need better/larger samples.

but

HST/GOODS very expensive (~700 orbits).

Can it be done from the ground?

A deep SN survey in the Subaru Deep Field

• 2-night runs on Subaru/Suprime-Cam, 0.25 deg2 field

• Re-image the SDF:

r, i ~ 27 mag z ~ 26 mag

Single-epoch photometric SN classification

D. Poznanski et al 2007

0.2% of the field

Record-holder: Most distant SN with spec-z (1.56)

33 SNe in 2 nights:

Every additional epoch adds ~40 SNe:

After two more successful runs in Feb and May 2007, + more in June 2008 ~150-200 SNe.

Soon: similar project with LBT-Italy on COSMOS field

Going to higher redshift with the new HST…

Surveying for high-z SNe with WFC3:

(predictions by K. Sharon)

Potential for SNe out to z~2.5:

predictions by K. Sharon)

Conclusions:

1. WFC3 can see SNe-Ia out to z~2.5, if there.

2. Will show if SN-Ia have short/long delay at high z.

3. Potentially extend Hubble diagram to decelaration era.

4. Find core-collapse SNe at z>1: SFR

5. Metal-enrichment in action over most of age of Universe.