Explosion Mechanisms ofCore-Collapse Supernovae and theMulti-Messenger Signatures
Kei Kotake（Fukuoka University)with Tomoya Takiwaki (NAOJ), Takami Kuroda (U. Basel),
Ko Nakamura (NAOJ), Yudai Suwa(Kyoto U.)
Kazuhiro Hayama (Osaka-city U.), Wakana Iwakami(Waseda U.)
Shio Kawagoe (U. Tokyo),Tomohide Wada(NAOJ),
Kohsuke Sumiyoshi (Numazu NC.), Shoichi Yamada (Waseda U.)
and Katsuhiko Sato (NINS)Supernovae and GRBs 2013
@ YITP, Kyoto Univ.

No (little!) doubt about ….. the key(Reviews: Mezzacappa +(2005), KK+(2006), Janka 2012,+(2013), Burrows (2013), KK+ 2012, 13)

Marek,Janka (09)Ott et al. (08)Suwa+ (09)Mueller+ (12)Mezzacappa+(98)
Bruenn+ (13)(Ohnishi + 06, Iwakami + 08,+11, Murphy& Burrows (08), Brondin & Mezzacappa(06)Fernandes & Thompson (09),Endeve + (11,13))

A list of recent “rad-hydro” milestones making “explosions”(e.g., KK + (2012))

Big breakthrough :✓Success of the neutrinomechanism: (shock-revival)
for 8.8 to 27 Msun stars
in 2D self- consistent
simulations !

(WH07)~15 successful models
But still,
The neutrino mechanism:

Unexplored >90 %(WH07)(WH07)

Systematic study needed:
Self-consistent (in 2D, firstly) sim.
to gain a “birds-eye view” of
explosion dynamics !

A list of recent “rad-hydro” milestones making “explosions”(e.g., KK + (2012))

Big breakthrough :✓Success of the neutrinomechanism: (shock-revival)
for 8.8 to 27 Msun stars
in 2D self- consistent
simulations !

~15 successful models(WH07)

But still,
The neutrino mechanism:

Unexplored >90 %(WH07)(WH07)

From 10.8 to 75 Msun star
More than 200 models(Woosley, Heger, Weaver
RMP (2002))

Systematic study needed:
Self-consistent (in 2D, firstly) sim.
to gain a “birds-eye view” ofexplosion dynamics !

1st topic: Our “birds-eye” project based on 2D rad-hyd. simulations
Nakamura et al. (2013). Suwa et al. (2013) in prep.

Numerics in both our 2D and 3D models:✓Spectral neutrino transport is solved by the IDSA scheme: (Liebendoerfer et al. 09)- with “ray-by-ray” approximation(as in Garching, OakRidge group)✓ “Standard” (Bruenn’s) neutrino opacities/emissivities (Bruenn (1985)).
Cooling by mu/nu neutrinos is treated by a leakage scheme.
(Inclusion of inelastic neutrino scattering (NES) in the IDSA scheme will be installed:
Takiwaki et al. in prep)✓ Lattimer-Swesty (1991) EOS (K=220 MeV) : compatible
Msun NS.
15 Mwithmodel2(WW95)
Color scale: entropy
from Suwa + (2013)✓ In 2D, nuclear burning included by alpha-network calculations.
sun“Four steps” from collapse to explosion(see, e.g., Suwa et al. 2010,2011,2013, ApJ)
1st : After bounce, bounce shock stalls (tpb < 10 ms).
2nd: Neutrino-driven convection and the SASI.
3rd: In the heating region,
dwell-time of material gets longer due
Key: “initialcondition” : “Progenitor”
to non-radialmotions.
4th:At around O(100)s ms after bounce,neutrino-driven explosions set in.

1st topic: Our “birds-eye” project based on 2D rad-hyd. simulations
Nakamura et al. (2013), Suwa et al. (2013) in prep
✓ “Systematics” from 100 solar-metalicity models from Woosley et al. (2002)

A Key : “Compactness: Mcore /Rcore”(See also, O’Connor & Ott (2012), Ugliano et al. (2013) but in 1D results)

Pre-collapse density profile

Compactness parameter✓ “Compactness” Not a monotonic function of progenitor mass !
- peaks around 20 - 30 Msun models (for WHW 02 progenitor).

Onset of explosion (t400 )Birds-eye view

Neutrino Luminosity @ t400

Nakamura, Takiwaki, Suwa, Kuroda, and KK in prep

More compact

More compact

Explosion explosion (diagnostic)“A good indicator to diagnose multi-D explosion character !”Convection vs. SASI in 2D11.2 Msun

Convection Dominant

The SASI
15.0 Msun

Convection

In 3DShock? Sloshing : SASI

Short summary - 2D multiple progenitor models:✓ Core-Compactness is a key to multi-D explosion systematics(explosion time, neutrino luminosity, diagnostic energy of explosion,
neutrino-convection vs. the SASI).
✓ ~98 % of our 2D models show shock revival, leading to explosions.
Long-term evolution : Needed to determine “final Eexp (increasing),
final Mrem (NS or BH), vkick, MNi, Lν, hGW …. etc.
(Nakamura et al (2013a,b) Suwa et al. (2013) in preparation).
(See Talks by M. Nakahata, N. Kanda, M. Was, G.McLaughlin, A. Wongwathanarat
K. Maeda, S. Blinnikov, N.Tominaga, posters by V. Utrobin S. Akihiro)

NorthSouth2nd topic: Can the neutrino mechanism work also in 3D?
Takiwaki et al. (2012,2013)“Low-resolution” photo“High resolution”

The First 3D neutrino mechanism inself-consistent CCSN simulation !

Tomoya Takiwaki

Supported by HPCI strategic program of MEXT
(program number hp120285)
Special Thanks to S. Aoki (YITP, chair of Joint institute of Computational Foundation
M. Shibata (YITP, chair of supercomputing committee in astrophysics)
J. Makino (Tokyo institute of technology)

Expected number of νe events at Super-K
from our self-consistent 3D model (Takiwaki , Kawagoe +2013 in prep)✓ Inverted hierarchy
11.2 Msun
5 MeV threshold
Betelgeuse✓ 3D simulation is
5 going on(Tsim : 300 ms)

LMC
Galactic center

Super-Kamiokande✓Typical horizon extends (at least) out to LMC.

3D vs. 2D✓ Update of Takiwaki et al. (2013), ApJL submiited

Comparison of average shock radii11.2 Msun star

(Mesh #NrNNΦ ）Theθ highest resolution(as of today)

2D

3D1D
✓ 2D leads to easier explosions !
(∵ In 2D, coherent motions develop along “the axis”.
In 3D, kinetic energy “cascades” via turbulence into smaller scale. )(see also, Iwakami+(08), Hanke + (2011), Burrows+ (2012), Dolence + (2012), Couch-O’Connor (2013))

Find possible ingredients to boost explosions !
Lots of new work (but mostly in 2D) ! (disclaimer; may be incomplete)
General Relativity (GR) : Mueller+ (2012a,b), Kuroda+ (2012)
Equation of state: Marek & Janka (2009), Suwa+ (2012), Couch (2012)
Nuclear burning: Mezzacappa+ (07), Nakamura+(2012), Yamamoto+(2013)
Microphysics missing : Sumiyoshi & Roepke (2008), Furusawa+(2013)
in simulations

Rotation
Magnetic fields

Collective neutrino
oscillation

Robert+(2012) (e.g., talks by Horowitz, Furusawa !): KK+(2003,2006), Marek&Janka(2009), Suwa+(2010): Yamada &Sawai (04), KK+06, Obergaulinger+06,Suwa+07, Burrows+07, Takiwaki+09, Endeve+(10,12) ,Obergauliner +(10), Obergaulinger & Janka (2013),
Masada+(2012), Sawai+(2013a,b)), Moiseenko(07,13): Suwa+(2012), Dasgupta+(2012), Pejcha+(2012)

Physic of hydrodynamics : Iwakami + (2013), Pejcha & Thompson(2012), Murphy& turbulence& Meakin (2011)
See Talks by Y. Suwa, M. Obergaulinger (in this session),
posters by W.Iwakami(P03), H.Sawai (P04), S.Moiseenko(P06), O. Pejcha (P62)Effects of rotation on neutrino-driven explosions (2/2)
Takiwaki and KK in prep
Rapid rotating(Ω0 = 2 rad/s)
Ω0 = 0.3 rad/s:
consistent withHeger(+05)

Angle-average

Ω0 = 1 rad/sΩ0 = 0.5 rad/s

Non-rotating
1D
13 Msun star (NH88)✓ Shock-revival time earlier as initial rotation rates higher.
✓ Rotation (mild as it is !) can boost neutrino-driven explosions.
✓ 3D sim. Needed because “rotation “ leads to non-axisymmetric modes.
(e.g., Spiral SASI models: e.g., Blondin & Mezzacappa (2007), Iwakami et al. (2008)

Will GR help “multi-D” neutrino-driven explosions?
Kuroda, KK, Takiwaki (2012 ApJ, 2013 PRD submitted)✓ 3D full GRMHD code developed by T. Kuroda (now in Basel. U)✓ Three-flavor approximate neutrino transport is implemented
based on the Thorne’s moment formalism (Shibata+ 2011,PTP)

Diagnostic of explosion : residency timescale/heating timescale
General Relativity
Special Relativity

15 Msun star(WW95)✓Only “3D-GR” model satisfies a necessary condition of explosion.
⇒ Suggestive : GR leads to easier explosions in multi-D.
(in line with 2D by B.Mueller et al. (2012a,b): GR with detailed transport)

by 3D-GRsimulations

Kuroda et al. (to be submitted soon)

27 Msun modelfrom WHW02

11.2 Msun modelfrom WHW02

SASI vs. Convection plot in 3D-GR

Should depend also on Ω0, B0…. Lots of work needed !

Gravitational-Wave Spectrogram (: Egw as time-frequency domain)
PromptConvection

PromptConvection
Violent SASI/
Convection

PromptConvection

data lost✓ “Excess power” blue-shifts with time ⇒ Traces the activity of SN engine !
(see, e.g., 2D: Murphy+(09), B.Mueller+(13), Yakunin+(09), e.g., Kotake (2013) for review)✓ Interesting: Late-time GW signals remarkable for models with high compactness :Expected to provide a possible hint about progenitor model !

Identifying SN mechanisms fromCoherent Network Analysis

Hayama, Kuroda,Takiwaki & KK(2013a,b) in prep

✓LIGOx2, VIGRO, KAGRA
SNR (Signal-to-Noise) ratio as a function of source distance

40Msun3D MHD (rapid rotation)

27Msun15Msun11.2Msun3D ν-driven models
A detection
thresholdLMC

10✓Method robust for ν-driven mechanism out to 10 kpc for massive progenitors.
✓Can identify for MHD mechanism out to LMC. (Birds-eye on GW is running !)Source identification test (10x10 degrees)

Hayama, Kuroda,Takiwaki & KK(2013b) in prep

Spatial location (LIGOx2, VIGRO, KAGRA) relative to astrophysical source

Hard to identify

Hard to identify
Assuming 3D model from KK et al. (2009) as a source

Detectors are ready!

Summary

1 :Based 2D multiple progenitor study (98 exploding models/100),“Compactness” is a key to characterize diversity of explosions.
2. From our 3D simulations with IDSA transport,✓ 2D leads to easier explosions than in 3D.
✓ First example of 3D neutrino mechanism (still under-energetic)✓ Mild rotation boosts neutrino-driven explosions.
✓ All in all, SN dynamics is of 3D nature !
3. From our 3D GR simulations with approximate transport✓ GR leads to easier explosions than Newtonian models.
✓ GW spectrogram imprints the SN post-bounce activity.
4. Coherent Network Analysis is robust for neutrino-driven
mechanism out to 10 kpc, and for MHD mechanism out to LMC.
Multi-messengers signatures being unveiled from first-principle 3D models:Coincident analysis should be important !

Many thanks !