Single Vs binary star progenitors of Type Iib Sne Niharika Sravan, pablo Marchant and vicky kalogera

time domain big data astronomy and supernovae Plethora of survey projects culminating with the LSST will transform SN science by providing unprecedented insights into supernova: Progenitors Environments

Time sensitivity Pre-SN variability Progenitor detection Late stage massive star evolution Stellar interactions Progenitor detection + Companions Light curve and spectral evolution – early detection important! Progenitor structure CSM interactions Remnants End-products of massive star evolution

Time sensitivity Reducing detection, classification and analysis overhead Need but lack comprehensive database of models in the relevant parameter space

A Systematic parameter space study of SN progenitors My work! Focus: Stripped Envelope Supernovae

Stripped Envelope (SE) Supernovae H He Core Type II STRIP! SUPERNOVA H He Core SE SNe (Types IIb,Ib,Ic) Core Core He SUPERNOVA

Stripped Envelope SupernoVae Important to understanding: stellar winds close binary interactions in massive star evolution MECHANISMS DOMINATING STRIPPING Single Star Progenitors Stellar Winds Binary Star Progenitors Close Binary Interactions

Test case: Type IIb SupernoVae

Type IIb SuperNovae Type II Type IIb SUPERNOVA STRIP! SN 2011dh He Core Type II 99d STRIP! SUPERNOVA time SN 2011dh 202d H He Type IIb Core SUPERNOVA Jerkstrand et al., 2015

Overview of Type IIb Sne Luminosity (L☉) Teff (K) Progenitor Observations Luminosity log10(L/L☉) = 4.72 – 5.4 Effective Temperature log10(Teff/K) = 3.58 – 3.8 Light Curves Hydrogen envelope mass 0.01 – 0.5 M☉ Helium core mass 2 – 6 M☉ Abundant ~ 11-12% a,b of all core-collapse SNe 30-40% a,b of all SE SNe Five with detected progenitors Only stripped envelope SN progenitor with detected binary companion a Li et al, 2011 b Smith et al, 2011 Type IIb

What are the Progenitors of type IIb Sne? Parameter search space Single star models*: M/M☉ = 10 – 80 Binary star models*: M1/M☉= 10 – 18 M2/M☉= 6 – M1 log10(Porb /d) = 0.0 – 4.0 Conservative and non-conservative MT *solar metallicity, non-rotating Type IIb

Physical Constraints to match for explaining Type IIb SN Progenitor observations Progenitor Properties HYDROGEN ENVELOPE MASS 0.01 – 0.5 M☉ HELIUM CORE MASS 2 – 6 M☉ LUMINOSITY log10(L/L☉) = 4.72 – 5.4 EFFECTIVE TEMPERATURE log10(Teff/K) = 3.58 – 3.8 Type IIb

Can single stars be type IIb Sn progenitors? Helium core mass Models Models with residual Hydrogen envelope mass 0.01 – 0.5 M☉ Observations Models Sravan et al., in prep Observations NO Luminosity and Teff Type IIb

Can binary stars be type IIb Sn progenitors? Parameter space occupied by binary star models reaching core-collapse with 0.01 – 0.5 M☉ residual Hydrogen envelope Can binary stars be type IIb Sn progenitors? Sravan et al., in prep Type IIb

Can binary stars be type IIb Sn progenitors? Helium core mass Models with residual Hydrogen envelope mass 0.01 – 0.5 M☉ Observations Sravan et al., in prep Models Observations Models Luminosity and Teff YES! Type IIb

Summary We find solar-metallicity, non-rotating single stars cannot be Type IIb progenitors Solar-metallicity, non-rotating binary stars can be Type IIb progenitors These systems have: Mass ratios > 0.6 3.2 < log10(Porb,i) < 3.6 Companion luminosity: 4 < log10(L/L☉)< 4.8 Predicted rate ~ 1% of all CC SNe

Future Work Complete parameter space: single star rotating models binary star models Mprim > 20M☉ Study light curves from IIb progenitor models

Thank you!