1. 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)

2. 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 1.1 10 6 yrs 60 Fe 60 Co 60 Ni 2 10 6 yrs5.3 yrs

3. 14 may 2007Simbol-X workshop - Bologna3 SNRs and 44 Ti  Exclusively produced in SNRs (first stages) 1.157 MeV (100 %) CE (99.3 %) Ti 44 22 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 44 21 Ca 44 20 44 Ti γ –ray lines ⇔ young SNR (few centuries)

4. 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 : 10 -6 -10 -5 M ʘ (Iwamoto et al. 99, Ropke 05) Sub-Chand. SNe :...10 -3 M ʘ (Woosley et al. 94, Livne & Arnett 95) Energy of the explosion (foe) Ejected mass (M ʘ )

5. 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 = 20-25 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 × 10 -4 M ʘ

6. 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 0.1 - 2.4 keV ( 44 Ca) 1.157 MeV ROSAT 1.3 - 2.4 keV  A lot of interrogations... (Slane et al. 01, Schönfelder et al. 00, Duncan et al. 00) Y 44 ?

7. 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 ~ 10 -4 M ʘ

8. 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) × 10 -4 M ʘ Solar 44 Ca abundance & Galactic chemical evolution model (Clayton 85) Current Galactic 44 Ti production = Y 44 × f SNe ~ 3.6 × 10 -4 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 ?

9. 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) × 10 51 erg (LH03, HL03) (Hwang et al. 01) (Hwang & Laming 03) Regions of pure Fe α -rich freezeout : 44 Ti

10. 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 (20-100 keV) = 3.3  F 44 = 2.2 × 10 -5 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

11. 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 ~ (2200-2800) km.s -1  At 78.4 keV : 3 σ velocity resolution ~ (4000-4500) km.s -1 Uniform 82" radius sphere 20’’ smoothing (courtesy of J. Ballet) Imaging capabilities

12. 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 = (0.8-2.3) × 10 -4 M ʘ (Motizuki & Kumagai 03) Expected F 44 = 3.5 × 10 -6 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 [2.1-6.5] +2.0 - 1.7

13. 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 × 10 -5 M ʘ F 44 ~ 5 × 10 -6 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 × 10 -6 cm -2 s -1 (Y 44 = 5.6 × 10 -5 M ʘ )

14. 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

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. G0.570-0.018, MAGPIS SNR-candidates