EARLY SUPERNOVA EMISSION - LOGARITHMIC CORRECTIONS TO THE PLANAR PHASE

Almog Yalinewich

Norm's Group Meeting

5.9.19

Hunt for the Progenitor

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?

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Forensics

Prompt

Breakout

Stellar Swan Song

Enter LSST

Physical Model

Explosion Mechanism

Shock Ascent

Distance from edge

Density

Velocity

Radiation Leak

x \approx D/v, \, D\approx \lambda c\Rightarrow \tau \approx c/v

Radiative Processes

Why photons come

Why they stay

\sigma \approx r_e^2
\dot{n}_{bs} \approx \frac{\alpha c}{r_e^4} \left(n_b r_e^3\right)^2 \sqrt{\frac{m_e c^2}{k T}}

Shock Temperature

k T_m \approx m_p v^2
\rho v^2 \approx a T_r^4
k T_r \approx \rho^{1/4} v^{1/2} c^{3/4} h^{3/4}
k T_p \approx m_e c^2
k T_s \approx m_e c^2 \left(\frac{m_p}{\alpha m_e}\right)^2 \left(\frac{v}{c}\right)^8

Homologous Expansion

v \approx \frac{r}{t}

Planar Expansion

t

x

Same shell

Luminosity

Watching the same shell cool

V \propto t \Rightarrow U \propto t^{-1/3} \Rightarrow L \propto t^{-4/3}

Energy Problem

Energy would run out after one diffusion time

We have to go deeper!

Today's Paper

Diffusion in an Expanding Medium

\frac{\partial u}{\partial t} = \frac{\partial}{\partial x} \left(D \frac{\partial u}{\partial x}\right)
D \approx \lambda c \approx \frac{1}{\kappa \rho}
dm = \rho dx \propto d \tau
\frac{d x}{d t} = \frac{x}{t} \Rightarrow \rho \approx m^{\zeta} t^{-1}
\frac{\partial u}{\partial t} \approx \rho \frac{\partial^2u}{\partial m^2} \approx \frac{m^{\zeta}}{t} \frac{\partial^2 u}{\partial m^2}
\tau \propto m \propto \left(\ln t\right)^{\frac{1}{2-\zeta}}

Effect on Luminosity

Effect on Temperature

Progenitor Models

Red Supergiant

Red Supergiant

Red Supergiant,

stronger explosion

Blue Supergiant

Blue Supergiant

Wolf Rayet

Logarithmic correction to planar shock breakout

By almog yalinewich

Logarithmic correction to planar shock breakout

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