Study of nuclear reactions on rare noble gas isotopes relevant to nuclear astrophysics  Page description

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Details of project

  
Identifier
49245
Type K
Principal investigator Somorjai, Endre
Title in Hungarian Ritka nemesgáz izotópokon lejátszódó nukleáris asztrofizikai reakciók vizsgálata
Title in English Study of nuclear reactions on rare noble gas isotopes relevant to nuclear astrophysics
Panel Physics 1
Department or equivalent Heritage science research group (HUN-REN Institute for Nuclear Research)
Participants Dombrádi, Zsolt
Elekes, Zoltán
Farkas, János
Fülöp, Zsolt
Gyürky, György
Kiss, Gábor
Starting date 2005-01-01
Closing date 2009-12-31
Funding (in million HUF) 7.800
FTE (full time equivalent) 10.53
state closed project





 

Final report

  
Results in Hungarian
A 3He(α,γ)7Be σ(E) hatáskeresztmetszetére a modellek min. 3,5% pontosságot igényelnek. A mérési eredmények erősen szórnak, ezért a reakciósebességet [σ(E)] 3 független módszerrel (aktiváció, g-hozam és „recoil” szeparátor) mértük meg. A 3 eredmény átlagértéke jobb a korábbiaknál, de pontossága még nem elegendő, további mérésekre van szükség. A CNO-ciklus más reakcióira [14,15N(p,g)15,16O] is új, meghatározó σ(E) értékeket adtunk meg (LUNA). A p-folyamat vizsgálatok során számos új reakciósebességet mértünk és összehasonlítottuk Hauser-Feshbach számolásokkal. Eredmény: proton keltette reakciókra az egyezés megfelelő, míg α-részecskékre nem. Pontos rugalmas α- szórásainkból kapott optikai potenciálokkal számolva sincs egyezés. A p-folyamat tanulmányozására egy új irányt, a (p,n) reakciók alkalmazását vezettük be. Az egyik kulcsreakció [124Xe(α,gamma)128Ba] méréséhez a kamra elkészült, tesztelése folyik. Méréseinkhez főleg aktivációs módszert használtunk, ezért mértük különböző anyagokba implantált aktív magok felezési idejének elméletileg jósolt változását. Sem anyag, sem hőmérséklet függést nem találtunk. Nemzetközi együttműködésben (OTKA IN64269) méréseket végeztünk az indirekt Trojan Horse Módszerrel. Bizonyítottuk a módszer asztrofizikai alkalmazhatóságát [7Li(p,α)4He], elsőként mértünk interferencia-mentes p-p szórást, valamint az 18O(p,α)15N és a 10,11B+p reakciókat az un. Gamow-ablakban (közel nulla energiánál).
Results in English
The 3He(α,γ)7Be is a key reaction (Big-Bang; Hydrogen Burning), the σ(E) cross section should be known with a precision of 3.5%. Because of discrepancies between different results, we measured it with 3 independent methods (activation, g-yield, recoil separator). The results are consistent, the average rate improved, however, the precision is still not enough. New σ(E) values were also determined for reactions important for CNO-cycle. Astrophysical p-process: a lot of new reaction rates were measured. The results were compared with Hauser-Feshbach calculations using different particle-nucleus potentials. Conclusion: for proton induced reactions the agreement is acceptable, contrary to α-particles. Optical potentials extracted from precise α-elastic scattering didn't solved the problem for α-s. A new idea, the applicability of (p,n) reactions in p-process studies was introduced. The key reaction, 124Xe(α,gamma)128Ba, is in test phase, the setup was developed. In our studies activation method was mostly used, therefore the predicted halflife changes of active nuclei implanted into different materials were checked. Neither host material nor temperature dependence was found. Experiments were performed by Trojan Horse Method in international collaboration (OTKA IN64269). The applicability of that indirect method was proved (7Li+p), first time the interference-free p-p scattering as well as the 18O+p and 10,11B+p reactions at close to zero energies (no extrapolation) were measured.
Full text https://www.otka-palyazat.hu/download.php?type=zarobeszamolo&projektid=49245
Decision
Yes





 

List of publications

  
Yalcin C. et al.,: 113In(alpha,gamma)117Sb and 113In(alpha,n)116Sb reaction cross section measurements and its importance in astrophysics, Proc. of X. National Nucl. Sci. and Techn. Conference, Mugla, Turkey. Vol.II.,103,, 2009
Fülöp Zs. et al.: Decay of 7Be in metallic environments,, Nucl. Phys. A758, 697, 2005
Tumino A. et al.: Nuclear proton-proton elastic scattering via the Trojan Horse Method,, AIP Conference Proceedings 1165, 335,, 2009
Kiss G. Gy. et al.: High precision 89Y(alpha,alpha)89Y scattering at low energies,, Phys. Rev. C80, 045807,, 2009
Rauscher T. et al.: Suppression of the stellar enhancement factor and the reaction 85Rb(p,n)85Sr,, Phys. Rev. C80, 035801,, 2009
Yalcin C. et al.: Odd p isotope 113In: measurement of alpha-induced reactions,, Phys. Rev. C79, 5801,, 2009
Broggini C. et al.: Underground nuclear astrophysics and the Sun,, Proc. of 28th Int. Symposium on Phys. in Collisions, 0, 67,, 2009
Broggini C. et al.: LUNA and the Sun,, AIP Conference Proceedings 1186, 1405,, 2009
Farkas J. et al.: Study of 74As decay in different host materials and at different temperatures,, Proceedings NIC X NICX, 209, 2009
Güray R. T. et al.: Measurement of alpha induced reaction cross sections on 113In relevant to the astrophysical p-process,, Proceedings NIC X NICX, 92, 2009
Imbriani G. et al.: Recent experiments at LUNA,, Proceedings NIC X NICX, 10, 2009
Kiss G. Gy. et al.: The 85Rb(p,n)85Sr reaction and the modified proton optical potential,, AIP Conference Proceedings 1090, 476,, 2009
Özkan N. et al.: Proton induced reactions on the p-nucleus 120Te,, Proceedings NIC X Proceedings NICX, 97,, 2009
Palumbo A. et al.: Proton induced reactions on the p-nucleus 120Te,, Proceedings NIC X Proceedings NICX, 46,, 2009
Spitaleri C. et al.: New results on the Trojan Horse Method applied to the 10,11B + p reaction,, AIP Conference Proceedings1120, 171,, 2009
Yalcin C. et al.: Astrophysical S-factor for alpha-capture of 113In in the p-process energy range,, AIP Conference Proceedings 1090, 931,, 2009
del Szanto M. G. et al.: Study of the 10B(p,alpha)7Be reaction through the Trojan Horse Method,, Proceedings of NIC X NICX, 224,, 2009
La Cognata M. et al.: Measurement of the 20 and 90 keV resonances in the 18O(p,alpha)15N reaction via the Trojan Horse Method, Phys. Rev. Letters 101, 152501, 2008
La Cognata M. et al.: A novel approach to measure the 18O(p,alpha)15N resonant reaction in the 0-200 keV energy range,, Astrophys. J. 708, 796,, 2010
Limata B.N. et al.: New measurement of 7Be half-life in different metallic environments, Eur.Phys.J. Supplement A27,193,2006, 2006
Raiola F. et al.: Enhanced d(d,p)t fusion reaction in metals, Eur.Phys.J. Supplement A27,79,2006, 2006
Di Leva A. et al.: Measurement of 3He(alpha,gamma)7Be with ERNA recoil separator, NIC IX. conference. Geneva,Switzerland 25-30 June 2006, 2006
Bemmerer D. et al.: Activation measurements of the3He(alpha,gamma)7Be cross section at low energy, Phys. Rev. Letters 97,12:2502, 2006
Costantini H. et al.: Towards a high precision measurement of the 3He(alpha,gamma)7Be cross section at LUNA, Eur.Phys.J. Supplement A27,177,2006, 2006
Wang B. et al.: Change of the 7Be electron capture half-life in metallic environments, Eur.Phys.J. A28,375,2006, 2006
Tumino A. et al.: Validity test of the Trojan Horse Method applied to the 7Li+p >> alpha+alpha reaction via the 3He break up, Eur.Phys.J. Supplement A27,243,2006, 2006
Özkan N. et al.: Astrophysical S factor for alpha-capture on 112Sn in the p-process energy range, Phys.Rev. C75, 2:5801, 2007
Gyürky Gy. et al.: 3He(alpha,gamma)7Be cross section at low energies, Phys. Rev. C75,3:5805, 2007
Gyürky Gy. et al.: Proton capture cross-section of 106,108Cd for the astrophysical p-process, J.Phys. G34,817, 2007
Tumino A. et al.: No signature of nuclear-Coulomb interference in the proton-proton elastic scattering via the Trojan Horse Method, Nucl.Phys. A787,337c, 2007
Confortola F. et al.: Astrophysical S factor of the 3He(alpha,gamma)7Be reaction measured at low energy via detection of prompt and delayed gamma rays, Phys.Rev. C75, 6:5803, 2007
Tumino A. et al.: Suppression of the Coulomb interaction in the off-energy-shell p-p scattering from the p+d>>p+p+n reaction, Phys.Rev. Letters 98,25:2502, 2007
Costantini H. et al.: The 3He(alpha,gamma)7Be S-factor at solar energies:The prompt gamma experiment at LUNA, Nucl. Phys. A814,144, 2008
Di Leva A. et al.: Recoil separatorERNA: Measurament of 3He(alpha,gamma)7Be, Nucl. Instr. and Methods A595, 381, 2008
Formicola A. et al.: Measurement of 25Mg(p,gamma)26Al resonance strengths via gamma spectrometry, J. Phys. G35, 014013, 2008
Gyürky Gy. et al.: Investigation of 74As decay branching ratio dependence on the host material, Eur. Phys. Letters 83, 2001, 2008
Gyürky Gy. et al.: Comparison of the LUNA 3He(alpha,gamma)7Be activation results with earlier measurements and model calculations, J. Phys. G35, 014002, 2008
Kiss G. Gy. et al.: Study of the 89Y(alpha,alpha)89Y reaction close to the Coulomb barrier, J. Phys. G35, 014037, 2008
Kiss G. Gy. et al.: Investigation of proton-induced reactions on Germanium isotopes, J. Phys. G35, 014032, 2008
Kiss G. Gy. et al.: Coulomb suppression of the stellar enhancement factor, Phys. Rev. Letters 101, 191101, 2008
Limata B.N. et al.: 7Be radioactive beam production at CIRCE and its utilization in basic and applied physics, Nucl. Instr. and Methods B266, 2117, 2008
Marta M. et al.: Precision study of ground state capture in the 14N(p,gamma)15O reaction, Phys. Rev. C78, 022802, 2008
Romano S. et al.: The Trojan horse method in nuclear astrophysics:resent results, J. Phys. G35, 014008, 2008
Trautvetter H-P. et al.: Ground state capture in 14N8p,gamma)15O studied above the 259 keV resonance at LUNA, J. Phys. G35, 014019, 2008
Tumino A. et al.: Off-energy-shell p-p scattering at sub-Coulomb energies via the Trojan horse method, Phys. Rev. C78, 4001, 2008
Kiss G.Gy. et al.: Experimental study of the variation of alpha elastic scattering cross sections along isotopic and isotonic chains at low energies, AIP Conference Proceedings 1016,221, 2008
Broggini C. et al.: LUNA results, Nucl. Phys. B Proceedings Suppl. 168, 103, 2007
Prati P. et al.: Nuclear astrophysics at LUNA: status and perspectives, AIP Conference proceedings 1012,305, 2008
Sergi M.L. et al.: Study of 17O(p,alpha)14N reaction via the trjan Horse Method for application to 17O nucleosynthesis, AIP Conference proceedings 1016 433, 2008
Spitaleri C. et al.: Recent astrophysical applications of the Trojan Horse Method to nuclear astrophysics, AIP Conference Proceedings 1016, 179, 2008
Tumino A. et al.: The Trojan Horse Method an indirect technique in nuclear astrophysics, J. Phys: Conference Series 111,012033, 2008
Tumino A. et al.: Proton-proton elastic scattering via Trojan Horse Method, Few-body Systems 43, 219, 2008
Bemmerer D. et al.: Direct measurement of the 15N(p,gamma)16O total cross section at novae energies, J. Phys. G36, 045202, 2009
Broggini C. et al.: LUNA and the neutrinos from the Sun, Nucl. Phys. B188, 124, 2009
Cacciolli A. et al.: Ultra-sensitive in-beam gamma-ray spectroscopy for nuclear astrophysics at LUNA, Eur. Phys. J. A39, 02179, 2009
Di Leva A. et al.: Stellar and primordinal nucleosynthesis of 7Be: measurement of 3He(alpha,gamma)7Be,, Phys. Rev. Letters 102, 232502,, 2009
Farkas J. et al.: Measurement of embedded 74As decay branching ratio at low temperatures,, J. Phys. G36, 105101,, 2009
Güray R.T. et al.: Measurement of proton-induced reaction cross section on 120Te for the astrophysical p process,, Phys. Rev. C80, 035804,, 2009
Gyürky Gy. et al.: Precise half-life measurement of the 10 h isomer in 154Tb,, Nucl. Phys. A828, 1,, 2009




 

Events of the project

  
2009-11-19 11:09:06
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