675 research outputs found

    KADoNiS-pp: The astrophysical pp-process database

    Full text link
    The KADoNiS-pp project is an online database for cross sections relevant to the pp-process. All existing experimental data was collected and reviewed. With this contribution a user-friendly database using the KADoNiS (Karlsruhe Astrophysical Database of Nucleosynthesis in Stars) framework is launched, including all available experimental data from (p,╬│\gamma), (p,n), (p,╬▒\alpha), (╬▒\alpha,╬│\gamma), (╬▒\alpha,n) and (╬▒\alpha,p) reactions in or close to the respective Gamow window with cut-off date of August 2012 (www.kadonis.org/pprocess).Comment: Proceedings Nuclear Data Conference 2013, published in Nuclear Data Sheets 120 (2014) 19

    pp-Process simulations with a modified reaction library

    Get PDF
    We have performed pp-process simulations with the most recent stellar (n,╬│)(n,\gamma) cross sections from the "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars" project (version v0.2, http://nuclear-astrophysics.fzk.de/kadonis). The simulations were carried out with a parametrized supernova type II shock front model (``╬│\gamma process'') of a 25 solar mass star and compared to recently published results. A decrease in the normalized overproduction factor could be attributed to lower cross sections of a significant fraction of seed nuclei located in the Bi and Pb region around the NN=126 shell closure.Comment: 5 pages, 1 figure Proceedings "Nuclear Physics in Astrophysics NPA-III", Dresden/Germany (2007

    Contributions to Reference Data Libraries

    Get PDF

    New Stellar (n,╬│)(n,\gamma) Cross Sections and The "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars"

    Get PDF
    Since April 2005 a regularly updated stellar neutron cross section compilation is available online at http://nuclear-astrophysics.fzk.de/kadonis. This online-database is called the "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars" project and is based on the previous Bao et al. compilation from the year 2000. The present version \textsc{KADoNiS} v0.2 (January 2007) includes recommended cross sections for 280 isotopes between 1^{1}H and 210^{210}Po and 75 semi-empirical estimates for isotopes without experimental information. Concerning stellar (n,╬│)(n,\gamma) cross sections of the 32 stable, proton-rich isotopes produced by the pp process experimental information is only available for 20 isotopes, but 9 of them have rather large uncertainties of Ôëą\geq9%. The first part of a systematic study of stellar (n,╬│)(n,\gamma) cross sections of the pp-process isotopes 74^{74}Se, 84^{84}Sr, 102^{102}Pd, 120^{120}Te, 130^{130}Ba, 132^{132}Ba, 156^{156}Dy, and 174^{174}Hf is presented. In another application \textsc{KADoNiS} v0.2 was used for an modification of a reaction library of Basel university. With this modified library pp-process network calculations were carried out and compared to previous results.Comment: Proceedings "International Conference on Nuclear Data for Science and Technology 2007", Nice/ Franc

    Stellar (n,gamma) cross sections of p-process isotopes PartI: 102Pd, 120Te, 130,132Ba,and 156Dy

    Full text link
    We have investigated the (n,gamma) cross sections of p-process isotopes with the activation technique. The measurements were carried out at the Karlsruhe Van de Graaff accelerator using the 7Li(p,n)7Be source for simulating a Maxwellian neutron distribution of kT = 25 keV. Stellar cross section measurements are reported for the light p-process isotopes 102Pd, 120Te, 130,132Ba, and 156Dy. In a following paper the cross sections of 168Yb, 180W, 184Os, 190Pt, and 196Hg will be discussed. The data are extrapolated to p-process energies by including information from evaluated nuclear data libraries. The results are compared to standard Hauser-Feshbach models frequently used in astrophysics.Comment: 13 pages, 4 figure

    Present status of the KADoNiS database

    Get PDF

    The Karlsruhe Astrophysical Database of Nucleosynthesis in Stars Project - Status and Prospects

    Get PDF
    The KADoNiS (Karlsruhe Astrophysical Database of Nucleosynthesis in Stars) project is an astrophysical online database for cross sections relevant for nucleosynthesis in the s process and the ╬│ process. The s-process database (http://www.kadonis.org) was started in 2005 and is presently facing its 4th update (KADoNiS v1.0). The ╬│-process database (KADoNiS-p, http://www.kadonis.org/pprocess) was recently revised and re-launched in March 2013. Both databases are compilations for experimental cross sections with relevance to heavy ion nucleosynthesis. For the s process recommended Maxwellian averaged cross sections for kT=5-100 keV are given for more than 360 isotopes between 1H and 210Bi. For the ╬│-process database all available experimental data from (p, ╬│), (p, n), (p, ╬▒), (╬▒, ╬│), (╬▒, n), and (╬▒, p) reactions between 70Ge and 209Bi in or close to the respective Gamow window were collected and can be compared to theoretical predictions. The aim of both databases is a quick and user-friendly access to the available data in the astrophysically relevant energy regions. ┬ę 2014 Elsevier Inc.Peer reviewe

    Adsorption and Reaction of Ethene on Cr2O3(0001)/Cr(110)

    Get PDF
    • ÔÇŽ
    corecore