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Supernova remnants (SNR) as ideal laboratories of hot plasmas Koyama Katsuji, Kyoto, and Osaka University Allow me to make an excuse remark … (1) To specialist (astronomer) = OK What are Chandrasekhar mass, Hubble constant, Stellar structure, SN and SNR. (2) To general public (citizen) = OK Big bang, Black hole Between (1) and (2) is very difficult. My talk is limited area of Astronomy : Hot plasma and Nucleosynthesis in SNRs Immediate after (0.4 Mys) the Big Bang: Chaos: “Ripples on the Pacific Ocean” only H, He 100 G stars http://sci.esa.int/planck/ Cluster of Galaxies C, O, Si, Fe Q: when and where ? A: SN, SNR After14 Gys: Islands: Cosmos What is SN, SNR ? By nuclear fusion, massive stars accumulate heavy elements in the interior (1) >10 M◎ : Fe core Core collapse supernova (CC SN: He, C, Ne, O) (2) 8-10 M◎ :C, Ne, O (white dwarf: degeneracy pressure) Explosive fusion Ia supernova (Ia SN : Fe) Supernova Remnant (SNR)= Shock Heated Hot Plasma C+Ne+O white dwarf degeneracy pressure Hot Plasma Space Plasma vs Laboratory Plasma Fundamental physics and Physical parameters are obtained from Laboratory Work Applied to the Space Space proper Science Are laboratory works always more accurate and reliable than the space ? No ! Steady nuclear fusion in laboratory is very difficult, almost impossible to keep hot plasma for long time is difficult. Laboratory plasma is always transient in a short time scale. Space plasma is also transient, but the time scale is extremely long quasi-stable Space is better than laboratory to study transient plasma Q: What is transient in the SNR plasma ? A: Shock-heating and relaxation process Transient Plasma =Ionizing plasma (IP) Expanding velocity (v) Random velocity (T) Free Expansion( v) X Shock Heated Gas In most of the SNR, Te > Tz (IP) . Standard Scenario Electron temperature, Te Ionization temperature: Tz Time t (~1000 ys) IP : (Te > Tz) CIE (Te=Tz) X-ray Spectrum of IC 443 (CC SNR) Ohnishi et al. 2013 Ne Mg Si Fe S Ar Ca All these lines come from highly ionized atoms No laboratory spectrum is like this ! Temperature kTe~ 0.6 keV is too low to make highly ionized iron Tz is higher than 0.6 keV to excite the lines Recombination of free electron Discovery of Te< Tz plasma = Recombing Plasma (RP) He-like ion: Excitation electron < Recombination of free electron RRC 1S 1 Origin of Recombining Plasma Rarefaction in an early phase of CC SN High density Circum Stellar Medium (CSM ) Te=Tz Break out to low density Inter Stellar Medium (ISM) Adiabatic expansion Te is cooled down Te<Tz log r (pc) ISM Low density 1 RP 0 CSM High density log t (year) 1 2 3 From these line fluxes, we can determine the abundance of each element Ne Mg Si Fe S Ar Ca The key issue is whether the plasma is ionizing, recombining, or equilibrium and what is the transient time Whether ionizing or recombining, and the transient time, historical SNe are important. We can depict the data of each time epoch, then can make quantitative model (theory). 10 11 12 log t (s) This is my “Star-of-bethlehem” SN1006 SN1573 (Tycho’s SN) SN1604 (Kepler’s SN SN185 : Himiko unified Japan (Yamatai Koku) Southern Cross Time history of recombination and ionization 1 Recombining Plasma 0.1 Bare Ion H-like He-like 0.01 9 Iron Ion Fraction 10 Li-like log t (s) for 11 n=1cm-3 12 Ionizing plasma We know the ion fraction from the spectrum , then we can obtain the abundances of each element Nucleosynthesis in massive star 1 Ia Supernova : Ia SN 8-10 M◎ :C, Ne, O (white dwarf) Explosive fusion (Si--Fe) C+Ne+O white dwarf Si--Fe SN1006 Fujiwara, Teika (藤原定家) Meigetsuki (明月記), Vol 52 一條院 寛弘三年 四月二日 葵酉 夜以降 騎官中 有大客 星 如螢惑 光明動耀 連夜正 見南方 或云 騎陣将軍星本 体 増変光 Constellation star Uchida et al. 2013 Then 1000 years after Koyama et al. 1996 Ia SN CC SN 100 ly Nucleosynthesis in massive star 2 Core collapse supernova : CC SN >10 M◎ He, C, Ne, O, Si SNR observations are “Anatomy” of massive stars Ia CC The progenitor stars are constrained to be ~25 M◎ Yasumi et al. 2013 Another topics : To thermal equilibrium, but in SN1006 opposite evolution (high temperature component becomes much higher). High energy electrons = Synchrotron radiation Ex=3keV (B/1μG)(Ee/1014 eV)2 Koyama et al. 1996 SN1006 Fermi Acceleration 2003-4-09 2012-4-23 V=6000 km/s Winkler et al. 2013 Ping-Pong ball on the moving frame Cosmic Rays : The Highest Energy Particles in the Universe : What is the Accelerator ? E-2.7 Knee Energy ~1015 eV E-3.0 Bellow Knee, Galactic Origin Above Knee, Extra Galactic LHC What is an injector to the Fermi accelerator ? SN1006: Synchrotron Radiation = Power-law with index Γ North Rim East Rim Flatter Γ Higher efficiency for the acceleration Γ vs kT North Rim vs East Rim Koyama &Bamba 2006 Γ-map kT-map Flatter Γ is from higher kT Injector is a high energy tail of hot plasma Conclusion 1. Space is better for the transient plasma than laboratory. 2. Using the transient plasma physics, we have established the Nucleosynthesis of stars and supper novae. 3. Anti-equilibrium of temperature: the Fermi acceleration is discovered in the SNR plasma Thank you Rarefaction in an early phase Canonical Diffusive Shock Acceleration Emax~ (v/2000 km/s)(B/10μG) 1014 eV < Knee Energy (1015 eV) log r (pc) ISM Low density 1 0 CSM High density log t (year) 1 2 3 Another big problem is missing energy Kinematic energy (=1/2Mv2) of Ia and CC SN are ~1051 erg. A large fraction should be converted to the thermal energy: kT = 3mv2/16 However observed thermal energy (kTe) is ~1049 erg This large missing energy would be contained in protons and other ions (the ion temperature kTi). But, no evidence is so far observed. Space plasma proper problem: large scale low density plasma. Solved by the observation of Tycho SNR Te=TFe me/mFe , 10-5 at the reverse shock front (RS) Then TFe Te as time goes. Question: How quick this energy Free Expansion( v) transfer process. Parameter β X β=10-5 (slow transfer) RS -- 100 (very rapid tarnsfer) RS 1-ly Energies of Kα & Kβ , and intensity ratio (Kα/Kβ ) are functions of Te and distribution of ion fraction. These are determined by β and nt. Simulations are right panels; The results are, n~2×10-24 g/cm3 β ~ 0.01 (large energy is still in ions) Thank you again