Pair Production Supernovae:Pair Production Supernovae:Theory and ObservationTheory and Observation

Evan ScannapiecoEvan ScannapiecoKavli Insitute for Theoretical Physics- UCSBKavli Insitute for Theoretical Physics- UCSB

Barkat etal (1967)Fraley (1968)

Appenzeller (1970)

Ober, El Id, & Frike (1983)

Bond, Arnet, & Carr (1984)Fryer, Woosley and Heger (2001)Umeda & Nomoto (2003)

Heger & Woosley (2002)

Pair Production SupernovaePair Production Supernovae

A. Songaila 2001Nonrotating stars that end their lives Nonrotating stars that end their lives with 140-260 Mwith 140-260 M

Heger & Woosley (2002)

Why Metal Free?Why Metal Free?

• 1. Because Pop III stars are thought to form with 1. Because Pop III stars are thought to form with higher intrinsic masses. higher intrinsic masses.

The 1st Objects: Why Massive?The 1st Objects: Why Massive?

Abel, Byran, Norman (2001)

HH22 cooling takes you to a cooling takes you to a

typical density of typical density of 101044 cm cm-3 -3 & T of 100 K& T of 100 K……. LTE. LTEMMjeansjeans ~ 1000 M ~ 1000 Msunsun

Why Metal Free?Why Metal Free?

• 1. Because Pop III stars are thought to form with 1. Because Pop III stars are thought to form with higher intrinsic masses due to wherehigher intrinsic masses due to where

H2 goes into LTE. (Bromm; Abel, Bryan and H2 goes into LTE. (Bromm; Abel, Bryan and Norman)Norman)

• 2. Because of mass loss in lower-Z stars. 2. Because of mass loss in lower-Z stars.

Very Massive Stars are Very Weakly BoundVery Massive Stars are Very Weakly Bound

Hyd. Bal.: EHyd. Bal.: EGG=-3pV=-3pVEETotTot=V(<K>-3p)=V(<K>-3p)

(nonrel. gas)(nonrel. gas)==33nkT-3nkTnkT-3nkT

22

Kudritski (2002)Kudritski (2002)

100 M100 M

300 M300 M

See also Vink etal (2001)See also Vink etal (2001)

M M ZZ1/21/2 or steeper or steeper

Caveat: Talk By Nathan SmithCaveat: Talk By Nathan Smith

(rel. gas)(rel. gas)=aT-3=aT-3aTaT=0!=0!

33

Why Metal Free?Why Metal Free?

• 1. Because Pop III stars are thought to form with 1. Because Pop III stars are thought to form with higher intrinsic masses due to wherehigher intrinsic masses due to where

H2 goes into LTE. (Bromm; Abel, Bryan and H2 goes into LTE. (Bromm; Abel, Bryan and Norman)Norman)

• 2. Because of mass loss in higher-Z stars (due to line 2. Because of mass loss in higher-Z stars (due to line driven winds)driven winds)

• 3. Because sufficiently high-mass stars are not seen 3. Because sufficiently high-mass stars are not seen today, even in very young clusters.today, even in very young clusters.

P<0.002P<0.002 P<0.02P<0.02

P<0.12P<0.12 P<0.47P<0.47

Figer (2005)Figer (2005)Oey & Clarke (2005)Oey & Clarke (2005)

4 4 r r22 dpdp = -G = -G dMdM MMdr dr dr r dr r22

p p MM22 4/34/3 M M2/32/3p p MM22 4/34/3 M M2/32/3

rr44

Gas + photonsGas + photonsDegeneracy PressureDegeneracy PressureLosses no longer Losses no longer importantimportant

unstableunstable

He/C/OHe/C/O

H/HeH/He

Pair Production SupernovaePair Production Supernovae

->e+e-->e+e-

H/HeH/He

H/HeH/He

C,O-C,O-

>Mg,Si,S,>Mg,Si,S,NiNi5656

Quick Facts:Quick Facts: EEkinkin: 10-100x10: 10-100x105151 ergs ergs

Mass: 140-260 MMass: 140-260 M

v: ~5,000 km/sv: ~5,000 km/sMass Metals: 20-200 MMass Metals: 20-200 M

Large Odd-Even EffectLarge Odd-Even Effect

ES, P. Madau, S. Woosley, A. Heger, A. Ferrara (2005)ES, P. Madau, S. Woosley, A. Heger, A. Ferrara (2005)

What do PPSNe look like? What do PPSNe look like?

Kepler, implicit (1-D) hydrodynamic codeKepler, implicit (1-D) hydrodynamic code

Single-temperature radiative diffusion, Single-temperature radiative diffusion, grey opacity. Includes radioactive decay.grey opacity. Includes radioactive decay.

1.1. Breakout Breakout 2.2. Adiabatic Expansion Adiabatic Expansion

+ H recombinations+ H recombinations3. Ni3. Ni5656 decay decay4. Becomes optically thin4. Becomes optically thin

ES, P. Madau, S. Woosley, ES, P. Madau, S. Woosley, A. Heger, A. Ferrara (2005)A. Heger, A. Ferrara (2005)

PPSN EvolutionPPSN Evolution

H/HeH/He

He/C/OHe/C/O

H/HeH/He

He/C/OHe/C/O

PPSN EvolutionPPSN Evolution

Dependent on: Dependent on: 1.1. Progenitor Size Progenitor Size 2.2. NiNi5656 Mass Mass

Mixing is keyMixing is key

PPSN LightcurvesPPSN Lightcurves

V-band,V-band, B-band,B-band, U-bandU-band

1. Not Always 1. Not Always Brighter Brighter

2. Long Evolution2. Long EvolutionTimesTimes

3. Hydrogen 3. Hydrogen

Tegmark, Silk, Rees, Blanchard, Abel, & Palla (1997)Abel, Byran, Norman (2001)

HH22 cooling takes you to a cooling takes you to a

typical density of typical density of 101044 cm cm-3 -3 & T of 100 K& T of 100 K……. LTE. LTEMMjeansjeans ~ 1000 M ~ 1000 Msunsun

HH22 Cooling Cooling

When Did TheyWhen Did They Happen? Happen?

““First Galaxies [PopII.5]”First Galaxies [PopII.5]”

Most metal free SF is going to occur Most metal free SF is going to occur in Tin Tvir vir 10 1044 K K

When Did Then Happen?When Did Then Happen?

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

MMsu

nsu

n/yr/

Mpc

/yr/

Mpc

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Enrichment is an Enrichment is an extended process that extended process that depends on ejection depends on ejection

efficiencyefficiencyES, R. Schneider, ES, R. Schneider, A. Ferrara (2003)A. Ferrara (2003)

0.01 M0.01 Msunsun/yr/Mpc/yr/Mpc33

0.01 x SFR0.01 x SFRobsobs

IfA Deep Survey:IfA Deep Survey: IIABAB > 26, 2.5 deg > 26, 2.5 deg22

COSMOS:COSMOS: IIABAB > 27, 2 deg > 27, 2 deg2 2

(general survey)(general survey)

Visible PPSNeVisible PPSNeI-bandI-band

Visible PPSNeVisible PPSNeNIRNIR

3 Versions of JDEM3 Versions of JDEM

0.01 M0.01 Msunsun/yr/Mpc/yr/Mpc33

0.01 x SFR0.01 x SFRobsobs

DESTINY (spec)DESTINY (spec)

SNAP (phot)SNAP (phot)

JEDI (phot)JEDI (phot)

Where do they end up locally?Where do they end up locally?

Although the oldest stars should be near the Although the oldest stars should be near the center of the galaxy, does extended primordial center of the galaxy, does extended primordial SF history change spatial distribution?SF history change spatial distribution?

ES, D. Kawata, C. Brook, R. Schneider, A. Ferrara, B. K. Gibson (2006)ES, D. Kawata, C. Brook, R. Schneider, A. Ferrara, B. K. Gibson (2006)

CDM “zoom in” sim. of 8x10CDM “zoom in” sim. of 8x101111 M M galaxy. galaxy.

• Pick out all objects above 10Pick out all objects above 1044 K limit. K limit.

• Use 1D model (varying wind efficency) to find Use 1D model (varying wind efficency) to find positions of metal-free stars.positions of metal-free stars.

(Tumlinson Talk)(Tumlinson Talk)

Milk Way ImplicationsMilk Way Implications

Milk Way ImplicationsMilk Way Implications

Milk Way ImplicationsMilk Way Implications

Milk Way ImplicationsMilk Way Implications

Milk Way ImplicationsMilk Way Implications

Milky Way ImplicationsMilky Way Implications

Lots of 1st stars Lots of 1st stars end up in the solar end up in the solar NeighborhoodNeighborhood

Good News for PPSN:Good News for PPSN:

No Metal free observed stars: MNo Metal free observed stars: Mminmin 0.8 M 0.8 M

Bad News: Bad News:

Odd even effect, Lack of Zn are not observedOdd even effect, Lack of Zn are not observed

<1/2 Fe from Pop II.5 is from PPSN<1/2 Fe from Pop II.5 is from PPSN

Tumlinson Venkatesan & Shull (2004)Tumlinson Venkatesan & Shull (2004)

ConclusionsConclusions

• PSSN- Why?PSSN- Why?• Losses from e+e- production moves Losses from e+e- production moves ≈4/3≈4/3 star to star to ≤4/3≤4/3. . • Explosive O/Si burning Explosive O/Si burning unbinds the starunbinds the star..

• PPSN -- Where and When?PPSN -- Where and When?• From From metal-free starsmetal-free stars (formation models, winds, observations) (formation models, winds, observations)• Extended redshift rangeExtended redshift range (enrichment is local) (enrichment is local)• z>4z>4 is interesting for direct constraints is interesting for direct constraints• products of metal-free stars end up in the products of metal-free stars end up in the solar neighborhoodsolar neighborhood

(good for high mass, bad for yields)(good for high mass, bad for yields)

• PPSN- How?PPSN- How?• Distinguished by: Hydrogen lines, Distinguished by: Hydrogen lines, slightlyslightly brighter than Ia, brighter than Ia, long evolution times -- possibly with 2 local maximalong evolution times -- possibly with 2 local maxima• Best method is Best method is NIRNIR surveys that cover surveys that cover a large area of skya large area of sky..