14 may 2007Simbol-X workshop - Bologna1 44 Ti nucleosynthesis γ –ray lines with Simbol-X Matthieu Renaud Max-Planck-Institute für Kernphysik Heidelberg, Germany Collaborators: F. Lebrun (CEA/SAp & APC), R. Terrier (APC, France) A. Decourchelle, J. Ballet (CEA/SAp & AIM, France)

14 may 2007Simbol-X workshop - Bologna2 SNRs and 44 Ti  Few radioactive elements accessible to gamma-ray astronomy  Limitations : short τ = important activity but γ blocked ( 56 Ni) long τ = weak flux...has to be abundant ( 26 Al) 56 Ni 56 Co 56 Fe 8.8 days111.3 days 57 Ni 57 Co 57 Fe 52 hours390 days 44 Ti 44 Sc 44 Ca 86 yrs5.4 hours 26 Al 26 Mg yrs 60 Fe 60 Co 60 Ni yrs5.3 yrs

14 may 2007Simbol-X workshop - Bologna3 SNRs and 44 Ti  Exclusively produced in SNRs (first stages) MeV (100 %) CE (99.3 %) Ti γ 78.4 keV (98.3 %) 67.9 keV (100 %) γ γ τ = 86 ans CE (0.7 %) β + (98.95 %) τ = 5.4 h Sc Ca Ti γ –ray lines ⇔ young SNR (few centuries)

14 may 2007Simbol-X workshop - Bologna4 SNRs and 44 Ti  From a theoretical point of view... Production sensitive to the details of the explosion (WW95, TNH96, LC03, RHHW02) cc-SNe : 0...~10 -4 M ʘ Std type Ia SNe : M ʘ (Iwamoto et al. 99, Ropke 05) Sub-Chand. SNe : M ʘ (Woosley et al. 94, Livne & Arnett 95) Energy of the explosion (foe) Ejected mass (M ʘ )

14 may 2007Simbol-X workshop - Bologna5 Counting rate Energy (keV) (Iyudin et al. 94) SNRs and 44 Ti  From an observational point of view... Few cases ! Cassiopeia A  Historical event (Flamsteed, 1680) ? (Stephenson & Green 02)  Dynamical age ~ 330 yrs, Distance ~ 3.4 kpc (Reed et al. 95)  Progenitor = M ʘ (Vink 04) but complete scenario ? (Young et al. 06) Nature of the continuum ? (Allen et al. 97 ; Vink & Laming 03) High 44 Ti/ 56 Ni... asymmetries ? Atypical explosion ? (Young et al. 06) (Vink et al. 01) BeppoSAX/PDS (Renaud et al. 06) IBIS/ISGRI Y 44 ~ 1.6 × M ʘ

14 may 2007Simbol-X workshop - Bologna6 SNRs and 44 Ti  From an observational point of view... Few cases ! Vela Junior  Detected by COMPTEL (Iyudin et al. 98) and ROSAT (Aschenbach 98)  Scenario « young & nearby » ?  Reality of the 44 Ti detection ? ROSAT keV ( 44 Ca) MeV ROSAT keV  A lot of interrogations... (Slane et al. 01, Schönfelder et al. 00, Duncan et al. 00) Y 44 ?

14 may 2007Simbol-X workshop - Bologna7 SNRs and 44 Ti  From an observational point of view... Few cases ! SN 1987a  Late-time light-curve explained by the 44 Ti decay (Fransson & Kozma 02) Y 44 ~ M ʘ

14 may 2007Simbol-X workshop - Bologna8 SNRs and 44 Ti  SNe → 44 Ti → 44 Ca: Origin of the Galactic 44 Ca & Search for « young & hidden » SNRs (Mahoney et al. 92, Leising & Share 94, Renaud et al. 04, The et al. 06) SNe rate ~ 2-3 century -1 (e.g. Cappellaro et al. 99) Y 44 (Cas A, SN1987a) ~ (1-2) × M ʘ Solar 44 Ca abundance & Galactic chemical evolution model (Clayton 85) Current Galactic 44 Ti production = Y 44 × f SNe ~ 3.6 × M ʘ.century -1  No significant 44 Ti excess in the Galactic plane (except Cas A) Constraints on the 44 Ti production in SNe Constraints on the SNe rate Scenario excluded at > 99 % ! (The et al. 06) Origin of the 44 Ca... Exceptionnal events ?

14 may 2007Simbol-X workshop - Bologna9 Scientific goals with Simbol-X  Where is the 44 Ti in Cas A ? (Hwang et al. 04) ~5’ R = Si B = Fe G = continuum 4-6 keV Asymmetric explosion  jet-counterjet structure  fast-moving knots (e.g. Fesen 01) E ~ (2-4) × erg (LH03, HL03) (Hwang et al. 01) (Hwang & Laming 03) Regions of pure Fe α -rich freezeout : 44 Ti

14 may 2007Simbol-X workshop - Bologna10 Scientific goals with Simbol-X  Where is the 44 Ti in Cas A ?... Visibility with Simbol-X in 100 ksec IBIS/ISGRI spectrum  Γ ( keV) = 3.3  F 44 = 2.2 × cm -2 s -1 Two 44 Ti-region sizes  Ф = 21’’ : point-like source  Ф = 164’’ : v = 4000 km.s -1 in 330 years at 3.4 kpc Two 44 Ti-region velocities  σ tot = 0.4 keV : v = 0 km.s -1  σ tot = 1.8 keV : v ~ 8500 km.s -1 (fast-moving knots, e.g. Fesen et al. 06 ) Ф = 21’’ σ tot = 0.4keV Ф = 21’’ σ tot = 1.8keV S/N[67.9keV] = 13.5 S/N[78.4keV] = 8 S/N[67.9keV] = 10.5 S/N[78.4keV] = 3.5 Ф = 164’’ σ tot = 0.4keV Ф = 164’’ σ tot = 1.8keV S/N[67.9keV] = 12 S/N[78.4keV] = 6 S/N[67.9keV] = 8 S/N[78.4keV] = 3

14 may 2007Simbol-X workshop - Bologna11 Scientific goals with Simbol-X  Where is the 44 Ti in Cas A ?... Visibility with Simbol-X in 100 ksec Spectral capabilities  At 67.9 keV : 3 σ velocity resolution ~ ( ) km.s -1  At 78.4 keV : 3 σ velocity resolution ~ ( ) km.s -1 Uniform 82" radius sphere 20’’ smoothing (courtesy of J. Ballet) Imaging capabilities

14 may 2007Simbol-X workshop - Bologna12 Scientific goals with Simbol-X  How much 44 Ti has been synthesised in SN 1987a ? distance = 51.4 ± 1.2 kpc (Panagia 99) age = 20 yrs nature of the progenitor : B3I blue SG Sanduleak -69◦202B3I Light-curve : Y 44 = ( ) × M ʘ (Motizuki & Kumagai 03) Expected F 44 = 3.5 × cm -2 s -1 (~4-12 less than Cas A) Exposure time = 1 Msec  S/N[67.9 keV] = 6.8 [3.5-11]  S/N[78.4 keV] = 4.0 [ ]

14 may 2007Simbol-X workshop - Bologna13 Scientific goals with Simbol-X  Tycho : How much 44 Ti can be synthesised in a Type Ia SN ? distance = 2.3 ± 0.8 kpc (Smith 91) age = 435 yrs (AD 1572) Prototype of a Type Ia SN ~8’ Constraints on the progenitor from the X-ray spectrum (Badenes et al. 03,05) → Y 44 ~ 5.6 × M ʘ F 44 ~ 5 × cm -2 s -1 ~ F 44, SN87a  Kepler : Type of the progenitor ? distance = 4.8 ± 1.4 kpc (Reynoso et al. 99) age = 403 yrs (AD 1604) and Ф = 3’ Nature ? F 44 ~ 2 × cm -2 s -1 (Y 44 = 5.6 × M ʘ )

14 may 2007Simbol-X workshop - Bologna14 Scientific goals with Simbol-X  Search for 44 Ti at the position of INTEGRAL candidates S Simbol-X = S IBIS/ISGRI / 15

14 may 2007Simbol-X workshop - Bologna15 Conclusions 44Ti γ –ray lines central in our understanding of SNe explosions Cas A  Localization of the 44 Ti (together with X-ray data)  Measurement of the 44 Ti velocity (dynamics) SN 1987a  Progenitor known (with distance and age)  Detection of the 44 Ti = unvaluable for the nucleosynthesis theory Tycho & Kepler SNRs  Detection ?  Strong constraints in the case of Tycho  Need of several pointings INTEGRAL candidates and others... Origin of the Galactic 44 Ca  e.g. G , MAGPIS SNR-candidates