Supernovae as birth sites of neutron stars Yudai Suwa YITP Yudai - PowerPoint PPT Presentation

Supernovae as birth sites of neutron stars Yudai Suwa （ YITP ）

Yudai Suwa @ NPCSM2016 First of all Thank you very much for coming to Kyoto and participating our long-term workshop! Hope you have enjoyed life in Kyoto Please come back again last but not least: 
 please acknowledge this long-term workshop when you declare new papers which are originated from here 2 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Supernovae make neutron stars Baade & Zwicky 1934 3 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Contents What we should explain with SN simulations NS formation Binary NS formation Magnetar formation 4 18/11/2016 /34

Yudai Suwa @ NPCSM2016 What we should explain with SN simulations 5 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Key observables characterizing supernovae Explosion energy: ~10 51 erg measured by fj tting SN Ni mass: ~0.1M ⦿ light curves Ejecta mass: ~ M ⦿ related measured by NS mass: ~1 - 2 M ⦿ binary systems fj nal goal of fj rst-principle ( ab initio ) simulations 6 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Explosion energy and Ni amount 100 92am M V , u ph 97D 87A 99br 10 0.1 M lg E = − 0 . 135 M V + 2 . 34 lg � t + 3 . 13 lg u ph − 4 . 205 , 0.01 lg M = − 0 . 234 M V + 2 . 91 lg � t + 1 . 96 lg u ph − 1 . 829 , lg R = − 0 . 572 M V − 1 . 07 lg � t − 2 . 74 lg u ph − 3 . 350 , 0.001 1 10 Nadyozhin 03 Hamuy 03 foe= f ifty- o ne- e rg, 10 51 erg 7 18/11/2016 /34

Yudai Suwa @ NPCSM2016 NS mass measurement From Lattimer’s talk in conference week 8 18/11/2016 /34

Yudai Suwa @ NPCSM2016 NS mass measurement From Freire’s talk in conference week 9 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Key observables characterizing supernovae Explosion energy: ~10 51 erg measured by fj tting SN Ni mass: ~0.1M ⦿ light curves Ejecta mass: ~ M ⦿ related measured by NS mass: ~1 - 2 M ⦿ binary systems fj nal goal of fj rst-principle ( ab initio ) simulations 10 18/11/2016 /34

Yudai Suwa @ NPCSM2016 What do simulations solve? Numerical Simulations Hydrodynamics equations Neutrino Boltzmann equation d ρ dt + ρ ∇ · v = 0 , 1 − µ 2 � ∂ f � � d ln ρ � � � cdt + µ ∂ f df + 3 v + 1 Solve ρ d v ∂ r + µ simultaneously cdt cr r ∂ µ dt = −∇ P − ρ ∇ Φ , � � d ln ρ � � + 3 v − v E ∂ f µ 2 + cdt cr cr ∂ E de ∗ e ∗ + P �� � � dt + ∇ · = − ρ v · ∇ Φ + Q E , E 2 v = j (1 − f ) − χ f + c ( hc ) 3 dY e � � � � Rf ′ dµ ′ − f dt = Q N , � 1 − f ′ � dµ ′ (1 − f ) R . × △ Φ = 4 π G ρ , ρ : density , v : velocity , P : pressure , Φ : f : neut. dist. func, µ : cos θ , E : neut. grav. potential, e * : total energy, Y e : energy, j : emissivity, χ : absorptivity, elect. frac., Q : neutrino terms R : scatt. kernel 11 18/11/2016 /34

Yudai Suwa @ NPCSM2016 What the community has done Multi-D (2D/3D) hydro. simulations in cooperation with multi-energy neutrino transfer (since 2006) Explosions obtained! phase transition from qualitative research (explode or not) to quantitative research (comparison w/ observations) Many systematics are under investigation EOS MHD GR 6D properties of neutrino transfer initial condition etc. 12 18/11/2016 /34

Yudai Suwa @ NPCSM2016 What the community has’t done yet Not enough explosion energy (E~10 50 erg) Not enough 56 Ni No full GR (magneto-)hydro. simulations with spectral neutrino transfer No 7D-neutrino transfer with hydrodynamics No consistent treatment of neutrino oscillation in transfer equation etc… 13 18/11/2016 /34

Yudai Suwa @ NPCSM2016 56 Ni production M( 56 Ni)=O(0.01)M ⊙ T>5x10 9 K is necessary for 56 Ni production Woosley+ 02 E=(4 π /3)r 3 aT 4 ➡ T(r sh )=1.33x10 10 (E/10 51 erg) 1/4 (r sh /1000km) -3/4 K With E=10 51 erg, r sh <3700km for T>5x10 9 K 56 Ni amount is more di ffj cult to explain than explosion energy Explosion energy can be topped up late after the onset of explosion (~O(1)s) 56 Ni should be synthesized just after the onset of the explosion (before shock passes O(1000)km, i.e. O(0.1) s) It would be a benchmark test for explosion simulations 14 18/11/2016 /34

Yudai Suwa @ NPCSM2016 deleted Analytic model for 56 Ni 15 18/11/2016 /34

Yudai Suwa @ NPCSM2016 To solve Ni and expl. ene. problems [Suwa & Müller, MNRAS, 460 , 2664 (2016)] S,Y e 10 11 s11.2 BC18 10 10 Y e4 10 9 S 5 Density (g cm -3 ) 10 8 Y e3 10 7 S 2 10 6 Y ec 10 5 S 1 10 4 S c M 10 100 1000 10000 M 1 M 2 M 3 M 4 M 5 Radius (km) 10 11 s11.2 M 1 : the edge of the fj nal convection in the BC18 10 10 radiative core 10 9 Density (g cm -3 ) M 2 : the inner edge of the convection zone 10 8 in the iron core 10 7 M 3 : the NSE core 10 6 M 4 : the iron core mass 10 5 M 5 : the base of the silicon/oxygen shell 10 4 0 0.5 1 1.5 2 Mass (M ⊙ ) 16 18/11/2016 /34

Yudai Suwa @ NPCSM2016 To solve Ni and expl. ene. problems [Suwa & Müller, MNRAS, 460 , 2664 (2016)] https://physik.unibas.ch/~liebend/download/ Agile-IDSA: 1D/GR/neutrino-radiation hydro code, publicly available 5 0.5 mass cut Maximum temperature Diagnostic Energy [10 51 erg] 4 0.4 Temperature (10 10 K) 4.7x10 51 erg/s 3 0.3 2 0.2 0.071M ⊙ T 9 =9 1 0.1 T 9 =5 0.083M ⊙ 0 0 1 1.1 1.2 1.3 1.4 0 0.1 0.2 Mass (M ⊙ ) Time after bounce [s] approx. 56 Ni mass 17 18/11/2016 /34

Yudai Suwa @ NPCSM2016 NS formation 18 18/11/2016 /34

Yudai Suwa @ NPCSM2016 From SN to NS [Suwa, Takiwaki, Kotake, Fischer, Liebendörfer, Sato, ApJ, 764 , 99 (2013); Suwa, PASJ, 66 , L1 (2014)] ejecta shock NS mass ~1.3 M � NS Progenitor: 11.2 M ⊙ (Woosley+ 2002) Successful explosion! (but still weak with E exp ~10 50 erg) The mass of NS is ~1.3 M ⊙ The simulation was continued in 1D to follow the PNS cooling phase up to ~70 s p.b. 19 18/11/2016 /34

Yudai Suwa @ NPCSM2016 From SN to NS [Suwa, PASJ, 66 , L1 (2014)] ν Crust formation! Z=50 Γ xThermal energy (C)NASA = Coulomb energy Z=70 Z=26 Γ ≡ ( Ze ) 2 rk B T = Coulomb energy Thermal energy ∼ 200 20 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Binary NS formation 21 18/11/2016 /34

Yudai Suwa @ NPCSM2016 How to make binary NSs? M ej 0.2M ⊙ 0.1M ⊙ SN 2005ek Time Tauris+ 2013 new class of SNe rapidly evolving light curve -> very small ejecta mass possible generation sites of Tauris & van den Heuvel 2006 binary neutron stars (synergy w/ gravitational wave!) 22 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Ultra-stripped type-Ic supernovae [Suwa, Yoshida, Shibata, Umeda, Takahashi, MNRAS, 454 , 3073 (2015)] shock radius [km] 
 Time after bounce (ms) Ejecta mass ~O(0.1)M ⊙ , NS mass ~1.4 M ⊙ , explosion energy ~O(10 50 ) erg, Ni mass ~O(10 -2 ) M ⊙ ; everything consistent w/ Tauris+ 2013 23 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Magnetar formations 24 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Magnetar � P ˙ B s ∝ P B Q = m 2 e c 3 = 4 . 4 × 10 13 G e � Subclass of neutron stars -9 10 Q E D -10 c r 10 i t P i c h Soft Gamma Repeater (SGR) a 10 o l 15 t o f i n e l G s d p l i t -11 10 r Anomalous X-ray Pulsar (AXP) y k 1 -12 10 . 0 10 14 G ) -1 -13 Period Derivative (s s 10 Surface magnetic fj eld from P & Ṗ r y k -14 0 10 1 10 13 ~10 14-15 G (>B Q =4.4x10 13 G) G -15 10 r y rotation period ~2-12s M -16 10 1 10 12 G -17 10 Death line 29 magnetars: 15 SGRs r y M 0 -18 0 10 1 10 11 (including 4 candidates), 14 G -19 Magnetar Suzaku Obs. 10 AXPs (including 2 candidates) as SNR Outbursts -20 10 Pulsar XDINS RRAT of 24/3/2016. 
 -21 10 -3 -2 -1 2 http://www.physics.mcgill.ca/~pulsar/magnetar/main.html 
 10 10 10 10 1 10 ( fj rst report was in 1979) Period (sec) Enoto, Shibata, Kitaguchi, Suwa+, submitted 25 18/11/2016 /34

Yudai Suwa @ NPCSM2016 Magnetar birth rate N mag ~30 (SGRs & AXPs) found in our Galaxy so far typical age: τ c ~10 4 years (estimated by characteristic age; P/2 Ṗ ) typical birth rate: 
 N mag / τ c ~10 -3 year -1 ~0.1 SN rate ~10% of SNe generate magnetars? observationally, N mag is increasing by ~1/year 100% of SNe generated magnetars at 100 years from Olausen & Kaspi 14 now? 26 18/11/2016 /34