I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Stellar lifetimes of SN isotopes Iris Dillmann, Alexey Evdokimov, Michele Marta Helmholtz Young Investigators Group "LISA- Lifetime Spectroscopy for Astrophysics"

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Influences on nuclear decay modes? Orbital-EC Continuum-state   -decay  + -decay (Q>1.022 MeV) Decay influenced by temperature (ionization and nuclear excitation) electron and positron density (free electron/positron capture) (ultra-)relativistic cosmic ray particles (fully stripped) Terrestrial conditions  -decay Ground-state decays Continuum-state   -decay Bound-state  -decay (Q+B e ): shorter t 1/2 (Free) positron capture Stellar conditions Fully ionized: stable (no EC) Orbital-EC of H/He-like ions (different t 1/2 ) (Free) electron capture  + -decay  -decay of fully ionized nuclei: No e - screening, longer t 1/2 Decays from excited states (faster) 2

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Phases after a SN explosion 3 1.) Supernova explosion: high temperatures (up to 10 GK)  fully ionized material ejected, recombination after 1000 s 2.) Free expansion phase (up to ~1000 y): re-ionization by reverse shock (up to 50 MK) Credit: NASA/CXC/MSFC/M.Weisskopf et al. 3.) Sedov-Taylor phase (~10 4 y): adiabatic expansion 4.) Snow plough phase (~10 9 y): radiative cooling 5.) Merging with ISM 6.) Re-acceleration by another SN shock front?  Cosmic ray particles (fully ionized particles)

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Bound-state  -decay 4 M. Jung et al., PRL 69, 2164 (1992). F. Bosch et al., PRL 77, 5190 (1996). T. Ohtsubo et al., PRL 95, (2005). 47 d 33 a 255 s ??? F. Bosch, Y.A. Litvinov, GSI proposal E100 Electron bb Anti-Neutrino A Z z+A Z+1 z+ K L ∞ K L ∞

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Hindered EC: 7 Be 5 Hydrogen burning: pp-II chain Lab: t 1/2 (EC)= d Sun: 7 Be 4+ (stable) (p,e + ) (p,  ) (,)(,) EC (p,  ) Core of the Sun: T 6 =15  ~100 g/cm 3 X(H)=Y(He)=0.5   s ( 7 Be)= 141 d Free continuum electrons available:

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th Ti from Cas A (SN~1680) 6 Can 44 Ti be ejected? Yield dep. on stellar mass & mass cut Are 44 Ti-producing SN exceptional ? Yield in M  Lifetime of 44 Ti Age of SNR Meas. flux: F  =(2.5 ±0.5)*10 -5  cm -2 s -1 Age of SN: t≈ 330 y Distance: d=3.4 kpc t 1/2 = 60.4 y (terrestrial) ► Yield( 44 Ti)= (0.8–2.5)*10 -4 M  Measured flux indicates 2-3x more ejected mass than modelled R. Diehl, "The origin of 44 Ti" Workshop (2009) COMPTEL Time- and position-dependence Y. Motizuki et al., Astr. Astroph. 346, 831 (1999) Wrong input parameters (stellar lifetime, reaction rates, …)?

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Indirect messenger from SN 7 Photons: direct way, indirect observation of nuclei Credit: ESO 60.4 a SN light curve 60.4 a COMPTEL & INTEGRAL/SPI R. Diehl, MPE Garching  -ray astronomy Observation of ongoing nucleosynthesis 228 keV 0 keV Mg E  = MeV 26 Al COMPTEL detection of 44 Ti from Cas A

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Galactic Cosmic Ray Particles 8 CR: indirect way, direct measurement of nuclei Ionized: trajectories along magnetic fields Re-accelerated by SN shock fronts E>300 MeV/u: fully stripped Primary SN isotopes vs. secondary CR (spallation/fragmentation) Electrons, ≈92% p, ≈ 7% He, ≈ 1% heavy nuclei

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 What can we learn from GCR? 9 CR: indirect way, direct measurement of nuclei  Primary EC SN isotopes ( 59 Ni): Time delay between SN production and acceleration Secondary long-lived isotopes (CR clocks )  Av. density of ISM during propagation: n H = / H at./cm 3  Mean confinement time within Galaxy: stable vs. long-lived (  -decay) CR  esc = /- 1.6 My  "Surviving fraction": depend on confinement time, spallation xs, in-flight decay  GCR spend more time in Gal. halo than in Gal. disk N.E. Yanasak et al., Astrophys. J. 563, 768 (2001)

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 What can we measure at GSI (FAIR) ? 10 1.Spallation cross sections up to GeV/u (+ detector tests) SPALADIN: 56 Fe + p (down to Z=8), e.g. Villagrasa-Canton et al., PRC 75, (2007) FIRST (Fragmentation of Ions Relevant for Space and Therapy): 12 C 2.Decay spectroscopy of weak decay branches (HISPEC/DESPEC?) Spectroscopy of weak  + /  - branches 3.(Stellar) t 1/2 of highly ionized nuclei in the storage ring(s) (ILIMA) n H = / H at./cm 3  esc = /- 1.6 My N.E. Yanasak et al., Astrophys. J. 563, 768 (2001) Main source of uncertainties : Spallation xs (Stellar) Half-life of 54 Mn

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 SN/CR isotopes 11 Mixed decay isotopes Pure EC decay isotopes SN isotopes Primary SN isotopes CR clocks Secondary CR spallation products

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012  + ~10 -5 % EC 1720 keV 970 keV 158 keV keV 0+ Mixed EC/  -decay isotopes Stellar conditions: EC hindered, weak  + /  - decay channel determines stellar t 1/2 2nd forb. (unique) transitions (cp. 10 Be, 26 Al): log ft=  t 1/2 =85000 y My 12  - ~10 -5 %  + ~10 -7 % EC 835 keV /2- EC 3/2-  + ~10 −5 %   

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th Mn 13 CR chronometer if partial t 1/2 of  - branch known  + branch measured Assuming same log ft for  - branch (factor 2-3 uncertainty)  - ~10 -5 %  + ~10 -7 % EC 835 keV 

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th Mn:  - branch 14 Direct measurement: 0.47 MBq (1.8*10 13 at. 54 Mn) Discrimination of background e - from internal conversion Compton scattering "shake-off" from excited nucleus Auger electrons contaminants   y Shell model prediction: t 1/2 (  - )~ y Martinez-Pinedo et al., PRL 81, 281 (1998) Kibedi et al., Astrophys. J. 489, 951 (1997)

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th Ni decay 15 ++ EC 1720 keV 970 keV 158 keV keV 0+  Most abundant isotope from SN explosions: early SN lightcurve (positrons) Measure for acceleration time scale if t 1/2 > 10 My Partial t 1/2 (  + ) 2+: ( )*10 8 y 3+: ( )*10 4 y 4+: ( )*10 12 y Quenching of GT, not for forbidden transition If quenched: t 1/2 (  + )= y  No CR chronometer Shell model predictions Lund Fisker et al., EPJA 5, 229 (1999) Measurement (0.1 MBq source, 8*10 10 at.):  + (158 keV) y Zaerpoor et al., PRC 59, 3393 (1999)

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Pure EC isotopes 16 X Z+ : stable X (Z-1)+ : t 1/2 (neutral) *2 ("H-like") X (Z-2)+ : t 1/2 (neutral) *9/8 ("He-like") Simple assumption: Adv. Composition Explorer (ACE)/ Cosmic Ray Isotope Spectrometer (CRIS): E= MeV/u, up to Z ≈ months measured (Dec Sept. 1999) Isotopic abundances (%)

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 EC of H- and He-like atoms 17 Assumption: t 1/2  always longer for orbital-EC of highly charged ions? X Z+ : stable X (Z-1)+ : t 1/2 (neutral) *2("H-like") X (Z-2)+ : t 1/2 (neutral) *9/8("He-like") GSI experiment in storage ring ESR:  + and EC decay of 140 Pr 59+,58+,57+ Y.A. Litvinov et al., PRL 99, (2007) N. Winckler et al., PLB 679, 36 (2009) t 1/2 (He-like)= 3.83 (16) min *9/8 t 1/2 (H-like)= 3.04 (9) min  *9/10 t 1/2 (neutral)= 3.39 (1) min Same observed for 142 Pm

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Explanation 18 Y.A. Litvinov et al., PRL 99, (2007) Conservation of total angular momentum of nucleus-lepton system EC decay rates of H- and He-like atoms depend on nuclear spins Z. Patyk et al., PRC 77, (2008) Theoretical description for allowed decays (  I= 0, +/-1, no parity change)

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Experimental Storage Ring 19 Single ion spectrometry: Direct measurement of the stellar decay branches Time-resolve Schottky spectrometry + particle detectors Picture: Y. A. Litvinov Momentum acceptance:  p/p≈ 2.5%: EC,  + /  - daughter: within acceptance  Schottky's  + /  - : if outside acceptance  particle detectors

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Possible measurements 20 "Easy" cases: Challenging (factor more ions needed): (weak  -branches) 10 7 pps injected, 30min measured  ~1 event/d if partial t 1/2 = y

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th SIS 100/300 HESR SuperFRS NESR CR RESR Isomeric beams, LIfetimes, and MAsses FAIR-CR:  p/p≈ 3.0%; 2 particle detectors (higher efficiency), several Schottky pickups, higher production rate

I. Dillmann - Annual NUSTAR Meeting – Feb. 29th 2012 Summary 22 EC hindered in GCR isotopes  weak  + /  - branches determine "stellar" half-life 54 Mn, 56 Ni: weak branches not well determined, large uncertainty in stellar half-life Isomeric beams, LIfetimes, and MAsses EC of H-/He-like ions: deviation from simple assumptions due to conservation of angular momentum More measurements needed…