Kocaeli University: AKTIVITIES. R. Taygun GÜRAY. ANNUAL MASCHE TEAM MEETING 26. November Goethe University - Germany

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1 Kocaeli University: AKTIVITIES R. Taygun GÜRAY 26. November Goethe University - Germany

2 Our Team in MASCHE B. Durkaya

3 Kocaeli University (IP/Turkey): p-processprocess (Laboratory Studies of Nucleosynthesis) M.S. Smith and K.E. Rehm, Ann. Rev. Nucl. Part. Sci, 51 (2001)

4 35 p-nuclei 74 Se 78 Kr 84 Sr 92 Nb 92 Mo 94 Mo 97 Tc 98 Tc 96 Ru 98 Ru 102 Pd 106 Cd 108 Cd 113 In 112 Sn 114 Sn 115 Sn 120 Te 124 Xe 126 Xe 130 Ba 132 Ba 138 La 136 Ce 138 Ce 144 Sm Sm 146 Sm Yb 174 Hf 180 Ta Ta Gd 156 Dy 158 Dy 162 Er 164 Er 180 W 184 Os long-lived radionuclides Os 190 Pt 196 Hg 152 Gd, 164 Er s-process contribution 113 In, 115 Sn s-process contribution (plus r-process)

5 p / γ-process reaction network Aim: reproduction of solar p-nuclei abundances ~ reactions on ~ 2000 nuclei mainly (γ,n), (γ,a), (γ,p) reactions and β-decays

6 modeling needs various input parameters stellar composition (p-process): Astrophysical site: Supernova II O/Ne layer Seed nuclei: s- and r-processes Temperature: 2-3 GK Time scale: order of s Nuclear physics Inputs: Decay properties, OMP, level density, gamma strength

7 need X-section measurements ( charged-particle induced reactions ) Reaction rates: lack of experimental data, so rates taken from statistical model calculations TEST IT! The γ-induced reaction rates can be calculated from the inverse capture reaction using detailed balance

8 List of p-nuclei with their solar and isotopic abundances Good candidates done

9 (p,γ) reactions: Astrophysical S factor σ(e) = S(E) (1/E) exp(-2πη) Good agreement (factor of 2) with NON-SMOKER but some of them not: Ru-98, Pd-105, Sn-114, Sn-116, Sn-119 (α,γ) reactions: NON-SMOKER overestimates measured values

10 Experimental efforts need cross sections of γ-induced reactions direct measurement only from ground state but to all particle channel -need γ- beam -activation method -prompt measurement difficult time inverse only from ground state but to all γ-channel -p-, α-, n- beam -activation method -prompt measurement -reactions involving unstable nuclei (inverse kinematics)

11 Charged particle induced reaction measurements: Activation method! easy if the reaction product is radioactive and its half-life life is appropriate decay parameters are known γ-radiation is sufficiently intense! But, for higher A low cross lower E high efficiency Rare isotopes enriched material High melting point preparation of target

12 What do we need? Experimental X-section # of (α,x)/(p, x) reactions # of emitted γ s from the products Gamma spectroscopy

13 Cd In Sn Region

14 Cd In Sn Region complex in terms of the contributing nucleosynthesis mechanisms due to the multiply-branched reaction flows in the s-,r- and p-processes 106 Cd(α,x) Gy. Gyürky, et al., Phys. Rev. C 74, (2006) 106 Cd(p,x) Gy. Gyürky, et al., J. Phys. G: Nucl. Part. Phys. 34, (2007) 112 Sn(α,x) N. Özkan et al., Phys. Rev. C 75, (2007) 113 In(α,x) C. Yalçın et al., Physical Review C 79, (2009) 120 Te(p,x) R. T. Güray et al., Physical Review C 75, (2009) 114,115,116 Sn(p,x) 114,115 Sn(α,x) being analyzed

15 112 Sn(α,γ) 116 Te N. Özkan et al., Phys. Rev. C 75, (2007) 113 In(α,γ) 116 Sb C. Yalçın et al., Physical Review C 79, (2009) 120 Te(p,γ) 121 I R. T. Güray et al., Physical Review C 75, (2009) 114,115,116 Sn(p,γ) 115,116,117 Sb and 114,115 Sn(α,γ) 118,119 Te An excellent case for testing the reliability of the Hauser-Feshbach prediction near the closed proton shell Z = 50 Analyses are under process Özkan N., Nuclei in the Cosmos IX, CERN, 2006.

16 Are they really p-nuclei p? Small production of Dy-158, Ta-180, W-180W No production of In-113, Sn-115, Gd-152, Er-164 In-113 : α induced reaction published Gd-152 : p induced reaction Er-162 : preliminary results NIC - XI Sn-115 : Er-162 : p and α induced reaction being analyzed Er :

17 as a summary Studies in the framework of EuroGENESIS/MASCHE: CURRENT 114,115,116 Sn(p,γ) 115,116,117 Sb 114,115,116 Sn(p,n) 115,116,117 Sb 114,115 Sn(α,γ) 118,119 Te 114,115 Sn(α,n) 118,119 Notre Dame 164 Er(p,γ) 165 Tm PLAN Dy-156 Hg Gd(p,γ) 153 Tb 152 Gd(p,n) 153 Tb 107 Ag(α,γ) 111 In 107 Ag(α,n) 110 ATOMKI 121 Sb(α,γ) 125 I 121 Sb(α,n) 124 I 123 Sb(α,n) 126 I

18 152 Gd(p,x) reaction NIC-XI, USA

19 107 Ag(α,γ) 111 In 2nd European Nuclear Physics Conference - EuNPC September 2012, Romania

20 107 Ag(α,n) 110 In

21 121 Sb(a,γ) 125 I CASTIGLION FIORENTINO WORKSHOP NEW FRONTIERS IN NUCLEAR ASTROPHYSICS June 18 22, 2012

22 121 Sb(a,n) 124 I

23 123 Sb(a,n) 126 I

24 164Er(p,γ)165 )165Tm

25 Contribution 151 Eu(a, γ ) 155 Tb & 151 Eu(a, n ) 154 Tb 110,116 Cd(α,α) 110,116 Cd 113, 115 In(α,α) 113,115 ATOMKI 64 Zn(α,α) 64 Zn

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