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
$^{1}$H and $^{210}$Po and 75 semi-empirical estimates for isotopes without
experimental information. Concerning stellar $(n,\gamma)$ cross sections of the
32 stable, proton-rich isotopes produced by the $p$ process experimental
information is only available for 20 isotopes, but 9 of them have rather large
uncertainties of $\geq$9%. The first part of a systematic study of stellar
$(n,\gamma)$ cross sections of the $p$-process isotopes $^{74}$Se, $^{84}$Sr,
$^{102}$Pd, $^{120}$Te, $^{130}$Ba, $^{132}$Ba, $^{156}$Dy, and $^{174}$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 $p$-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

Dillmann, I.

Domingo-Pardo, C.

Heil, M.

Käppeler, F.

Plag, R.

Rauscher, T.

Thielemann, F. -K.

English

arXiv

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 KADoNIS v0.2 (January 2007) includes recommended cross sections for 280 isotopes between H-1 and (210)po and 75 semi-empirical estimates for isotopes without experimental information. Concerning stellar (n,gamma) cross sections of the 32 stable, proton-rich isotopes produced by the p process experimental information is only available for 20 isotopes, but 9 of them have rather large uncertainties of <= 9 systematic study of stellar (n,gamma) cross sections of the p-process isotopes Se-74, Sr-84, Pd-102, Te-120, Ba-130, Ba-132, Dy-156, and Hf-174 is presented. In another application KADoNIS v0.2 was used for an modification of a reaction library of Basel university. With this modified library p-process network calculations were carried out and compared to previous results

Kaeppeler, F.

edoc

New stellar (n,γ) cross sections and the "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars"

Crossref

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 KADoNIS v0.2 (January 2007) includes recommended cross sections for 280 isotopes between (1)H and (210)po and 75 semi-empirical estimates for isotopes without experimental information. Concerning stellar (n,gamma) cross sections of the 32 stable, proton-rich isotopes produced by the p process experimental information is only available for 20 isotopes, but 9 of them have rather large uncertainties of >= 9%. The first part of a systematic study of stellar (n,gamma) cross sections of the p-process isotopes (74)Se, (84)Sr, (102)Pd, (120)Te, (130)Ba, (132)Ba, (156)Dy, and (174)Hf is presented. In another application KADoNIS v0.2 was used for an modification of a reaction library of Basel university. With this modified library p-process network calculations were carried out and compared to previous results

Thielemann, Friedrich-Karl

University of Hertfordshire Research Archive

arXiv:0806.2076v1  [astro-ph]  12 Jun 2008Proceeding ”International Conference on Nuclear Data for Science and Technology 2007”New Stellar (n, γ) Cross Sections and The ”KarlsruheAstrophysical Database of Nucleosynthesis in Stars”I. Dillmann,∗ R. Plag,† C. Domingo-Pardo, and F. KäppelerInstitut für Kernphysik, Forschungszentrum Karlsruhe,Postfach 3640, D-76021 Karlsruhe, GermanyM. HeilGesellschaft für Schwerionenforschung mbH,Plankstrasse 1, D-64291 DarmstadtT. Rauscher and F.-K. ThielemannDepartement Physik und Astronomie, Universität Basel,Klingelbergstrasse 82, CH-4056 Basel, SwitzerlandAbstractSince April 2005 a regularly updated stellar neutron cross section compilation is available on-line at http://nuclear-astrophysics.fzk.de/kadonis. This online-database is called the ”KarlsruheAstrophysical Database of Nucleosynthesis in Stars” project and is based on the previous Bao etal. compilation from the year 2000. The present version KADoNiS v0.2 (January 2007) includesrecommended cross sections for 280 isotopes between 1H and 210Po and 75 semi-empirical estimatesfor isotopes without experimental information. Concerning stellar (n, γ) cross sections of the 32stable, proton-rich isotopes produced by the p process experimental information is only availablefor 20 isotopes, but 9 of them have rather large uncertainties of ≥9%. The first part of a systematicstudy of stellar (n, γ) cross sections of the p-process isotopes 74Se, 84Sr, 102Pd, 120Te, 130Ba, 132Ba,156Dy, and 174Hf is presented. In another application KADoNiS v0.2 was used for an modificationof a reaction library of Basel university. With this modified library p-process network calculationswere carried out and compared to previous results.∗Electronic address: iris.dillmann@ik.fzk.de; also at Departement für Physik und Astronomie, UniversitätBasel.†now at Gesellschaft für Schwerionenforschung mbH, Plankstrasse 1, D-64291 Darmstadt1I. STELLAR NEUTRON CAPTURE COMPILATIONSThe pioneering work for stellar neutron capture cross sections was published in 1971by Allen and co-workers [1]. In this paper the role of neutron capture reactions in thenucleosynthesis of heavy elements was reviewed and a list of recommended (experimentalor semi-empirical) Maxwellian averaged cross sections at kT= 30 keV (MACS30) presentedfor nuclei between C and Pu.The idea of an experimental and theoretical stellar neutron cross section database waspicked up again by Bao and Käppeler [2] for s-process studies. This compilation publishedin 1987 included cross sections for (n, γ) reactions (between 12C and 209Bi), some (n, p) and(n, α) reactions (for 33Se to 59Ni), and also (n, γ) and (n, f) reactions for long-lived actinides.A follow-up compilation was published by Beer et al. in 1992 [3].In the update of 2000 the Bao compilation [4] was extended down to 1H and – like theoriginal Allen paper – semi-empirical recommended values for nuclides without experimentalcross section information were added. These estimated values are normalized cross sectionsderived with the Hauser-Feshbach code NON-SMOKER [5], which account for known sys-tematic deficiencies in the nuclear input of the calculation. Additionally, the database pro-vided stellar enhancement factors and energy-dependent MACS for energies between kT=5 keV and 100 keV.The KADoNiS project [6] is based on these previous compilations and aims to be aregularly updated database. The current version KADoNiS v0.2 (January 2007) is alreadythe second update and includes - compared to the previous Bao et al. compilation [4]- 38updated and 14 new recommended cross sections. The update history can be followed inthe section “Logbook”. A paper version of KADoNiS (“v1.0”) is planned for 2008, whichalso will – like the first Bao compilation from 1987 [2]– include (n, p) and (n, α) reactionsfor light isotopes and (n, γ) and (n, f) reactions for long-lived actinides at kT= 30 keV.Additionally, a re-calculation of semi-empirical estimates based on the latest experimentalresults of neighboring nuclides will be performed.2II. SYSTEMATIC STUDY OF (n, γ) CROSS SECTIONS FOR THE p PROCESSA. The “p processes”The “p process” is responsible for the production of 32 stable but rare isotopes between74Se and 196Hg on the proton-rich side of the valley of stability. Unlike the remaining 99%of the heavy nuclei beyond iron these isotopes cannot be created by neutron captures inthe s process or r process, and their solar [7] and isotopic abundances [8] are 1-2 ordersof magnitude lower than the respective s- and r-process nuclei. The bulk of p isotopesis thought to be produced in explosive O/Ne burning during supernova type II explosions(core collapse supernovae). This mechanism is called “γ process” since the main reactionsare photo-induced reactions of high energy photons (T9= 2-3) on pre-existing seed nucleifrom prior s-processing. The “γ process” can reproduce the solar abundances [7] of most pisotopes within a factor of 3 [9, 10].For the missing abundances of the most abundant isotopes 92,94Mo and 96,98Ru alternativeprocesses have been proposed, e.g. using strong neutrino fluxes in the “νp process” [11], orrapid proton-captures in the “rp process” [12] in a binary, cataclysmic system with a neutronstar accreting material from a Red Giant.Apart from the astrophysical uncertainties of the p-process site another problem arisesfrom the large nuclear physics uncertainties due to missing experimental cross section data.Present network calculations for the reproduction of the solar abundances of the 32 p-processisotopes include up to now only the γ-process scenario since it seems to be the best under-stood part of the p processes. Such network calculations are carried out with a typicalreaction library consisting of ≈1600 isotopes which are connected by several thousands ofreactions [13, 14]. The largest fraction of these reactions concerns short-lived radioactive nu-clei and thus have to be inferred from theoretical work, e.g. the Hauser-Feshbach statisticalmodel [5, 15].Some experimental information for the p process is available for charged-particle reactions,but the largest amount of data concerns (n, γ) data, which is connected via detailed balancewith the respective (γ, n) reactions needed for the γ process. However, most of this neutroncapture data was measured with the activation technique at one single energy (kT=25 keV),and thus has to be extrapolated to the respective γ-process energies (kT=170-260 keV) with3the help of energy-dependencies from Hauser-Feshbach theory. This method was used in themodification of a reaction library discussed in Sec. III.B. Experimental techniqueThe previous status of (n, γ) cross sections for the 32 p isotopes at kT= 30 keV is listedin the third column of Table III [4]. Experimental data was available for 20 isotopes but9 of them (92,94Mo, 96Ru, 124,126Xe, 130Ba, 156Dy, 180W, and 190Pt) exhibited uncertaintieslarger than 9%. For the remaining 12 isotopes no experimental information was availablein the stellar energy range, where only semi-empirical estimates based on Hauser-Feshbachpredictions existed.This motivated an extended measuring campaign at the Karlsruhe 3.7 MV Van de Graaffaccelerator using the activation technique. In this framework the p isotopes 74Se, 84Sr, 102Pd,120Te, 130Ba, 132Ba, 156Dy, and 174Hf were measured with samples of natural composition.Neutrons were produced via the 7Li(p, n)7Be reaction by bombarding 10-30 µm thick layersof metallic lithium or lithiumfluoride on a water-cooled copper backing with protons of Ep=1912 keV, 31 keV above the 7Li(p, n) reaction threshold at 1881 keV. The resulting quasi-stellar neutron spectrum approximates a Maxwellian distribution for kT= 25.0 ± 0.5 keV[16] but is truncated at En= 106 keV. Under these conditions, all neutrons are kinematicallycollimated into a forward cone of 120◦ opening angle. Neutron scattering through the Cubacking is negligible, since the transmission is ≈98% in the energy range of interest.The sample materials were either metals (Se, Pd, Te, Dy, and Hf) or compounds (SrO,SrCO3, SrF2, BaCO3). Thin pellets were pressed from the respective powders or granulesand enclosed in cans made from thin aluminium foil. In case of Pd, Dy, and Hf the sampleswere cut from thin metal foils. During the activations the samples were sandwiched between10-30 µm thick gold foils of the same diameter and were irradiated in close geometry to theneutron target. In this way the neutron flux can be determined relative to the well-knowncapture cross section of 197Au [16]. The activation measurements were carried out with theVan de Graaff accelerator operated in DC mode with a current of ≈100 µA (for the Litargets) or even higher currents (up to 150 µA) for the LiF targets. The mean neutron fluxover the period of the activations was ≈1.5-3×109 s−1 at the position of the samples. Toensure homogeneous illumination of the entire surface the proton beam was wobbled across4the Li target. During the irradiation the neutron flux was recorded in intervals of 60 s or90 s using a 6Li-glass detector for later correction of the number of nuclei which decayedduring the activation.For the measurement of the induced activities two detector setups were available. Asingle high purity Germanium (HPGe) detector with a well defined geometry and 10 cm leadshielding was used in all cases for the counting of the gold foils, as well as for the activitiesof 75Se, 85Sr, 121Te, 131Ba, 133mBa, 157Dy, and 175Hf. The activities of 103Pd and 133gBa weremeasured with a gamma detection system consisting of two HPGe Clover detectors [17] inclose geometry. The decay properties of the determined product nuclei are given in Table I.The sample and activation parameters are shortly summarized in Table II.C. ResultsFor a detailed description of the data analysis and the results, see [14, 28, 29]. Theresulting Maxwellian averaged cross sections at kT=30 keV from this measuring campaignare shown in Table III in bold. The semi-empirical estimates for 74Se, 102Pd, 120Te, 132Ba, and174Hf are reproduced within the large error bars of the prediction. The previous experimentalvalues for 130Ba and 156Dy are confirmed perfectly but with much improved uncertainties.Thus, only 6 p isotopes (98Ru, 138La, 158Dy, 168Yb, 184Os, and 196Hg) remain withoutany experimental information about the stellar neutron cross section. The present work istherefore being extended to the heavier p isotopes and includes the measurement of 158Dy,168Yb, 184Os, and 196Hg, and the re-measurement of 180W and 190Pt. Only for 98Ru and138La the activation technique cannot be applied.III. p-PROCESS SIMULATIONS WITH AN UPDATED REACTION LIBRARYThe p-process network calculations in [13, 14] were carried out with the program”pProSim” [13, 30]. The underlying network was originally based on a reaction libraryfrom Michigan State University for X-ray bursts, which included only proton-rich isotopesup to Xenon. For p-process studies it was extended with a full reaction network library fromBasel university [31]. This reaction library is mainly based on NON-SMOKER predictions[5] with only a few experimental information for light nuclei, and was modified with the5TABLE I: Decay properties of the product nuclei. Shown here are only the strongest transitionsused for the analysis.Isotope t1/2 Eγ [keV] Iγ [%] Ref.75Se 119.79 (4) d 136.0 58.3 (7) [18]264.7 58.9 (3)85Srg 64.84 (2) d 514.0 95.7 (40) [19]85Srm 67.63 (4) min 151.2 12.9 (7)231.9 84.4 (22)103Pd 16.991 (19) d 357.5 2.21×10−2 (7) [20]121Teg 19.16 (5) d 573.1 80.3 (25) [21]121Tem 154 (7) d 212.2 81.4 (1)1102.1 2.54 (6)131Bag 11.50 (6) d 123.8 29.0 (3) [22]216.1 19.7 (2)373.2 14.0 (2)496.3 46.8 (2)133Bag 10.52 (13) yr 356.0 62.1 (2) [23]133Bam 38.9 (1) h 275.9 17.8 (6) [24]157Dy 8.14 (4) h 326.3 92 (4) [25]175Hf 70 (2) d 343.4 84.0 (30) [26]198Au 2.69517 (21) d 411.8 95.58 (12) [27]latest stellar neutron capture cross sections available from KADoNiS v0.2. This modifica-tion includes more than 350 experimental and semi-empirical (n, γ) cross sections and wasextended to the respective (γ,n) channels calculated via detailed balance.pProSim simulates the abundance evolution for the 32 p isotopes with a parameterized6TABLE II: Activation schemes and sample characteristics. Φtot is the total neutron exposure ofthe sample during the activation.Isotope N(Isotope) tact Φtot[atoms] [min] [neutrons]74Se (0.7-1.4)×1019 419-1425 (0.2-1.5)×101484Sr→g (0.2-1.3)×1019 1234-2621 (0.8-1.6)×101484Sr→m (0.4-0.8)×1019 155-274 (1.1-3.3)×1013102Pd (1.7-2.6)×1019 5751-9770 (3.5-8.2)×1014120Te→g,m (1.6-2.0)×1018 1406-4142 (1.5-3.1)×1014130Ba (3.5-4.8)×1017 4014-7721 (2.7-6.9)×1014132Ba→g,m (3.3-4.7)×1017 4014-7721 (2.7-6.9)×1014156Dy (0.6-1.8)×1017 362-964 (4.0-9.5)×1013174Hf (5.0-8.8)×1017 3865-5451 (5.1-8.7)×1014model of a supernova type II explosion of a 25 M⊙ star. Since the p-process layers are locatedfar outside the collapsing core, they only experience the bounced shock front passing throughthe O/Ne burning zone and the subsequent temperature and density increase. Both, the seedabundances and the respective temperature and density profiles, were taken from externalworks and not calculated self-consistently (for more information, see [13]).The results from the simulations with the modified reaction library were compared tothe results published in [13] to examine the influence of the experimental neutron capturedata. This was done with help of the so-called “normalized overproduction factor”, whichis =1 when the calculated abundance corresponds to the solar abundances [7]. Ranges ofvariations of this factor for SN type II explosions with star masses 13 M⊙≤ M⋆≤25 M⊙ arepublished e.g. in Fig. 4 in [10].The new overproduction factors are slightly below previously published values [10, 13]due to the inclusion of recent experimental data, especially in the mass range 150≤A≤170where the main reaction flux is driven by (γ, n), (γ, α), (n, γ), and (n, α) reactions. All of7these reaction fluxes are found to be smaller. Our study underlines the importance of (n, γ)and (γ, n) reactions in the p-process flow. For example, we were able to show that a variationin the neutron rates of the Pb and Bi isotopes has a strong impact on the above mentionedfluxes. This is due to the fact that a significant fraction of the seed abundances is locatedin these isotopes and converted to nuclei at lower mass by photodisintegration sequencesstarting with (γ, n) reactions on Pb and Bi. Also the importance of experimental data isstrongly emphasized by these findings. Because of the magicity or near-magicity of the Pband Bi isotopes, individual resonances determine the cross sections and the Hauser-Feshbachtheory is not applicable [32, 33]. From discrepancies between resonance and activationmeasurements [34, 35] and from theoretical considerations [36], it has been previously foundthat even a small direct capture component contributes to neutron capture on Pb [32, 36].Resonant and direct capture contributions are difficult to handle in theoretical models andexperiments prove to be indispensable.AcknowledgmentsWe thank E. P. Knaetsch, D. Roller and W. Seith for their help and support during theneutron irradiations at the Karlsruhe Van de Graaff accelerator. This work was supportedby the Swiss National Science Foundation Grants 2024-067428.01 and 2000-105328.[1] B. Allen, J. Gibbons, and R. Macklin, Adv. Nucl. Phys. 4, (1971) 205.[2] Z. Bao, and Käppeler, At. Data Nucl. Data Tables 36, (1987) 411.[3] H. Beer, F. Voss, and R. Winters, Ap. J. Suppl. 80, (1992) 403.[4] Z. Bao, H. Beer, F. Käppeler, F. Voss, K. Wisshak, and T. Rauscher, At. Data Nucl. DataTables 76, (2000) 70.[5] T. Rauscher and F.-K. Thielemann, At. Data Nucl. Data Tables 75, (2000) 1.[6] I. Dillmann, M. Heil, F. Käppeler, R. Plag, T. Rauscher, and F.-K. Thielemann, Proc. 12thInternational Symposium on Capture Gamma-Ray Spectroscopy and Related Topics (CGS 12),Notre Dame, IN/USA, AIP Conference Proceedings 819 (2006) 123.[7] E. Anders and N. Grevesse, Geochim. Cosmochim. Acta 53, (1989) 197.8[8] K. Rosman and P. Taylor, Pure and Appl. Chem. 70, (1998) 217.[9] M. Rayet, N. Prantzos, and M. Arnould, Astron. Astrophys. 227, (1990) 271.[10] M. Rayet, M. Arnould, M. Hashimoto, N. Prantzos, and K. Nomoto, Astron. Astrophys. 298,(1995) 517.[11] C. Fröhlich, G. Martinez-Pinedo, M. Liebendörfer, F.-K. Thielemann, E. Bravo, W.R. Hix,K. Langanke, and N.T. Zinner, Phys. Rev. Lett. 96, (2006) 142502.[12] H. Schatz, A. Aprahamian, J. Görres, M.C. Wiescher, T. Rauscher, J. Rembges, F.-K. Thiele-mann, B. Pfeiffer, P. Möller, H. Herndl et al., Phys. Rep. 294, (1998) 167.[13] W. Rapp, J. Görres, M. Wiescher, H. Schatz, and F. Käppeler, Ap. J. 653, (2006) 474.[14] I. Dillmann, Ph.D. thesis, University of Basel (2006).[15] W. Hauser and H. Feshbach, Phys. Rev. 87, (1952) 366.[16] W. Ratynski and F.Käppeler, Phys. Rev. C 37, (1988) 595.[17] S. Dababneh, N. Patronis, P.A. Assimakopoulos, J. Görres, M. Heil, F. Käppeler, D. Kara-manis, S. O’Brien, and R. Reifarth, Nucl. Instr. Meth. A 517, (2004) 230.[18] A.R. Farhan and B. Singh, Nucl. Data Sheets 86, (1999) 785.[19] H. Sievers, Nucl. Data Sheets 62, (1991) 271.[20] D. de Frenne and E. Jacobs, Nucl. Data Sheets 93, (2001) 447.[21] T. Tamura, Nucl. Data Sheets 90, (2000) 107.[22] Yu.V. Sergeenkov, Yu.L.Khazov, T.W. Burrows, M.R. Bhat, Nucl. Data Sheets 72, (1994)487.[23] R. Shaheen, Nucl. Data Sheets 75, (1995) 491.[24] Yu.V. Sergeenkov and V.M. Sigalov, Nucl. Data Sheets 49, (1986) 639.[25] R.G. Helmer, Nucl. Data Sheets 103, (2004) 565.[26] M.S. Basunia, Nucl. Data Sheets 102, (2004) 719.[27] Z. Chunmei, Nucl. Data Sheets 95, (2002) 59.[28] I. Dillmann, M. Heil, F. Käppeler, T. Rauscher, and F.-K. Thielemann, Phys. Rev. C 73,(2006) 015803.[29] C. Vockenhuber, I. Dillmann, M. Heil, F. Käppeler, N. Winckler, W. Kutschera, A. Wallner,M. Bichler, S. Dababneh, S. Bisterzo, and R. Gallino, Phys. Rev. C 75, (2006) 015804.[30] W. Rapp, Report FZKA 6956, Forschungszentrum Karlsruhe (2004).[31] Online: http://download.nucastro.org/astro/reaclib9[32] A. M. Lane and J. E. Lynn, Nucl. Phys. 17 (1960) 586.[33] T. Rauscher, F.-K. Thielemann, and K.-L. Kratz, Phys. Rev. C 56, (1997) 1613.[34] R. L. Macklin, J. Halperin, and R. R. Winters, Ap. J. 217 (1977) 222.[35] H. Beer, F. Corvi, and P. Mutti, Ap. J. 474 (1997) 843.[36] T. Rauscher, R. Bieber, H. Oberhummer, K.-L. Kratz, J. Dobaczewski, P. Möller, and M. M.Sharma, Phys. Rev. C 57 (1998) 2031.10TABLE III: Status of MACS30 of all 32 p nuclei. Isotopic abundances were taken from [8]. Rec-ommended cross section were taken from [4] and [6]. Italic values show semi-empirical estimates.*Preliminary semi-empirical value based on KADoNiS v0.2. **Preliminary value, data analysisnot yet fully completed.Isotope Isotopic Recommended MACS30abundance [8] previous [4] new [6][%] [mb] [mb]74Se 0.89 (4) 267 ± 25 271 ± 15 [28]78Kr 0.35 (1) 312 ± 2684Sr 0.56 (1) 368 ± 125 300 ± 17 [28]92Mo 14.84 (35) 70 ± 1094Mo 9.25 (12) 102 ± 2096Ru 5.54 (14) 238 ± 60 207 ± 898Ru 1.87 (3) 173 ± 36102Pd 1.02 (1) 373 ± 118 370 ± 14106Cd 1.25 (6) 302 ± 24108Cd 0.89 (3) 202 ± 9113In 4.29 (5) 787 ± 70112Sn 0.97 (1) 210 ± 12114Sn 0.66 (1) 134.4 ± 1.8115Sn 0.34 (1) 342.4 ± 8.7120Te 0.09 (1) 420 ± 103 499 ± 24124Xe 0.09 (1) 644 ± 83126Xe 0.09 (1) 359 ± 51130Ba 0.106 (1) 760 ± 110 767 ± 30132Ba 0.101 (1) 379 ± 137 399 ± 16136Ce 0.185 (2) 328 ± 21138Ce 0.251 (2) 179 ± 511

New stellar (n,gamma) cross sections and the "Karlsruhe Astrophysical Database of Nucleosynthesis in Stars"

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 KADoNiS v0.2 (January 2007) includes recommended cross sections for 280 isotopes between 1H and 210Po and 75 semi-empirical estimates for isotopes without experimental information. Concerning stellar (n,γ) cross sections of the 32 stable, proton-rich isotopes produced by the p process experimental information is only available for 20 isotopes, but 9 of them have rather large uncertainties of ≥9%. The first part of a systematic study of stellar (n, γ) cross sections of the p-process isotopes 74Se, 84Sr, 102Pd, 120Te, 130Ba, 132Ba, 156Dy, and 174Hf is presented. In another application KADoNiS v0.2 was used for an modification of a reaction library of Basel university. With this modified library p-process network calculations were carried out and compared to previous results

I. Dillmann

R. Plag

C. Domingo-Pardo

M. Heil

F. Käppeler

T. Rauscher

F.-K. Thielemann

EDP Sciences OAI-PMH repository (1.2.0)

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

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

Abstract

Similar works

Full text

Available Versions

edoc

Crossref

University of Hertfordshire Research Archive

EDP Sciences OAI-PMH repository (1.2.0)

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

Abstract

Similar works

Full text

Available Versions

edoc

Crossref

University of Hertfordshire Research Archive

EDP Sciences OAI-PMH repository (1.2.0)

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