超新星爆発へ向けた親星からの予兆～前兆ニュートリノの放出と観測可能性

The sign from the progenitors for the supernova explosions～the emissions of pre-SN neutrinos and their detection possibilities

Waseda univ. Yamada lab.
D1 Chinami KATO

Collaboration with S. Yamada(Waseda), H. Nagakura (Caltech), S. Furusawa(Frankfurt),
K. Takahashi (UT), T. Yoshida (UT), H. Umeda (UT), K. Ishidoshiro (Tohoku)

Our target

Pre-SN neutrinos

Our research target
数MeV orderOutline☑ Introduction☑ Purpose☑ Methods☑ Results☑ Summary & Future work

Massive Star Evolution & Neutrino～107yr

２０s

1s

Stellar evolution

Corecollapse

Supernova

The trigger of corecollapse is EC

Neutrino cooling decides
core evolution

ONe core collapse
2024e   e    e  eplasmon  e  e  e  e

PNScoolingNe 20 F  20 OMg  24 Na  24 Ne

Fe core collapsee   p νe  n

Massive Star Evolution & Neutrino～107yrCorecollapse

Stellar evolution

Matter accretion

ννν
ν
ν

２０s

1s

Neutrinos give energy
to stalled shockνe  p  e   nνe  n  e   p

Stalled shockPNScoolingSupernova

Neutrinos cool
PNS towards NSn  p  e  n  N  p  N  e  νννＰＮＳ

Importance of observations～107yr1s

Stellar evolution

Corecollapse

Pre-SN neutrino✓ structure of SN progenitor
・progenitor type・convection property
・nuclear burning process
・EOSetc.

Neutronization burst

Supernova

２０sPNScoolingSN neutrino✓ mechanism of SN explosion✓ nucleosynthesis of heavy nuclei✓ EOS✓ BH formation etc.

Importance of observations
Galactic supernova rate : a few / 100years⇒ We must not miss one chance !

✓Multi-messenger:
the first alert for SN !
✓warning system: SNEWS”SuperNova Early warning system”
Nakamura et al.(2016)

Purpose of present research
Can we detect pre-SN neutrinos ?
Brown Dwarf
White Dwarf

Neutron StarBlack HoleElectron
Capture SNFe Core
Collapse SN

ＳＡＧＢ
ＲＧ

H

H
He

ＡＧＢ

H
He
C+O

HHe

C+O

HHe
C+OSiFeO+NeMETHODS

Step.1 Back ground calculation） Iron core
ONe core

Collapsing phase
C. Kato et al.
H.Nagakura(Caltech) et al.

Stellar evolution phase
K. Takahashi et al.

Step.2 neutrino spectrum & luminosity
Post process

densitytemperatureYeνe distribution

luminosity & spectrum

Neutrino emission processes✓thermal neutrino✓nuclear weak interactione   e    e  epair annihilation
plasmon  e   e    e  eplasmon decaye     e   e  ephotoe   nucleus  e   nucleus  e  e

brems

brems

Itoh et al. (1996)

Pure Fe medium✓electron capture by free protone   p  n  e

Number luminosity/s

Neutrino luminosities

Neutrino luminositiesNumber luminosity/ssolid：electron anti-neutrino
dashed：electron neutrino

ElectronCapture SNFe Core
Collapse SN

explosion

Spectrum

explosionNeutrino detectors
Water Cherenkov

Liquid scintillator

Neutrino detectors✓low backgroundEX) SK+Gd✓νe detection

Set up of estimation✓reaction
Inverse-β decay

νenp

e+

Survival probability✓Neutrino oscillation・adiabatic oscillation
・3 flavor mixing

normalinverted

νe

νe

0.675
0.024

0.02340.3007

R=200pc

SKHK

KamLAND

JUNO

DUNE

threshold (MeV)

5.3

8.3

1.81.85.0

target number N

2.1×1033

3.6×1034

8.5×1031

1.7×1033

6.0×1033

Event numbers
ElectronCapture SNFe Core
Collapse SN

Number of events

nuebnue• Anti-neutrinos : we can distinguish 2 types ofprogenitors, the alert for SN• Neutrinos : we can get core information regardlessof progenitor types

Summary & future work
☑ We focus on the 2 different types SN progenitors.
☑ At first, we calculate the background hydrodynamic values☑ By post-process calculation, we get continuous neutrino
luminosity from stellar evolution phase until core bounce.
☑ anti-neutrinos: 2 types of progenitors by pre-SN neutrinos
alert for following SN
neutrinos: give information about core of both progenitors☑ calculate neutrino luminosities & spectrum about many
progenitor initial masses☑ detail physics derived from the observations

Thank you forlistening !

Future study

Continuous neutrino spectrum & luminosity calculationof whole massive star evolutions
Stellar evolutionCorecollapse

Supernova

PNS
cooling

Pre-SN neutrino

SN neutrino

present research

now going…