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  1. Article ; Online: Direct Measurement of the ^{13}C(α,n)^{16}O Cross Section into the s-Process Gamow Peak.

    Ciani, G F / Csedreki, L / Rapagnani, D / Aliotta, M / Balibrea-Correa, J / Barile, F / Bemmerer, D / Best, A / Boeltzig, A / Broggini, C / Bruno, C G / Caciolli, A / Cavanna, F / Chillery, T / Colombetti, P / Corvisiero, P / Cristallo, S / Davinson, T / Depalo, R /
    Di Leva, A / Elekes, Z / Ferraro, F / Fiore, E / Formicola, A / Fülöp, Zs / Gervino, G / Guglielmetti, A / Gustavino, C / Gyürky, Gy / Imbriani, G / Junker, M / Lugaro, M / Marigo, P / Masha, E / Menegazzo, R / Mossa, V / Pantaleo, F R / Paticchio, V / Perrino, R / Piatti, D / Prati, P / Schiavulli, L / Stöckel, K / Straniero, O / Szücs, T / Takács, M P / Terrasi, F / Vescovi, D / Zavatarelli, S

    Physical review letters

    2021  Volume 127, Issue 15, Page(s) 152701

    Abstract: One of the main neutron sources for the astrophysical s process is the reaction ^{13}C(α,n)^{16}O, taking place in thermally pulsing asymptotic giant branch stars at temperatures around 90 MK. To model the nucleosynthesis during this process the reaction ...

    Abstract One of the main neutron sources for the astrophysical s process is the reaction ^{13}C(α,n)^{16}O, taking place in thermally pulsing asymptotic giant branch stars at temperatures around 90 MK. To model the nucleosynthesis during this process the reaction cross section needs to be known in the 150-230 keV energy window (Gamow peak). At these sub-Coulomb energies, cross section direct measurements are severely affected by the low event rate, making us rely on input from indirect methods and extrapolations from higher-energy direct data. This leads to an uncertainty in the cross section at the relevant energies too high to reliably constrain the nuclear physics input to s-process calculations. We present the results from a new deep-underground measurement of ^{13}C(α,n)^{16}O, covering the energy range 230-300 keV, with drastically reduced uncertainties over previous measurements and for the first time providing data directly inside the s-process Gamow peak. Selected stellar models have been computed to estimate the impact of our revised reaction rate. For stars of nearly solar composition, we find sizeable variations of some isotopes, whose production is influenced by the activation of close-by branching points that are sensitive to the neutron density, in particular, the two radioactive nuclei ^{60}Fe and ^{205}Pb, as well as ^{152}Gd.
    Language English
    Publishing date 2021-10-22
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.127.152701
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Bonn / Germany

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  2. Article ; Online: The baryon density of the Universe from an improved rate of deuterium burning.

    Mossa, V / Stöckel, K / Cavanna, F / Ferraro, F / Aliotta, M / Barile, F / Bemmerer, D / Best, A / Boeltzig, A / Broggini, C / Bruno, C G / Caciolli, A / Chillery, T / Ciani, G F / Corvisiero, P / Csedreki, L / Davinson, T / Depalo, R / Di Leva, A /
    Elekes, Z / Fiore, E M / Formicola, A / Fülöp, Zs / Gervino, G / Guglielmetti, A / Gustavino, C / Gyürky, G / Imbriani, G / Junker, M / Kievsky, A / Kochanek, I / Lugaro, M / Marcucci, L E / Mangano, G / Marigo, P / Masha, E / Menegazzo, R / Pantaleo, F R / Paticchio, V / Perrino, R / Piatti, D / Pisanti, O / Prati, P / Schiavulli, L / Straniero, O / Szücs, T / Takács, M P / Trezzi, D / Viviani, M / Zavatarelli, S

    Nature

    2020  Volume 587, Issue 7833, Page(s) 210–213

    Abstract: Light elements were produced in the first few minutes of the Universe through a sequence of nuclear reactions known as Big Bang nucleosynthesis (BBN) ...

    Abstract Light elements were produced in the first few minutes of the Universe through a sequence of nuclear reactions known as Big Bang nucleosynthesis (BBN)
    Language English
    Publishing date 2020-11-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-020-2878-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

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  3. Article ; Online: Direct Capture Cross Section and the E_{p}=71 and 105 keV Resonances in the ^{22}Ne(p,γ)^{23}Na Reaction.

    Ferraro, F / Takács, M P / Piatti, D / Cavanna, F / Depalo, R / Aliotta, M / Bemmerer, D / Best, A / Boeltzig, A / Broggini, C / Bruno, C G / Caciolli, A / Chillery, T / Ciani, G F / Corvisiero, P / Davinson, T / D'Erasmo, G / Di Leva, A / Elekes, Z /
    Fiore, E M / Formicola, A / Fülöp, Zs / Gervino, G / Guglielmetti, A / Gustavino, C / Gyürky, Gy / Imbriani, G / Junker, M / Karakas, A / Kochanek, I / Lugaro, M / Marigo, P / Menegazzo, R / Mossa, V / Pantaleo, F R / Paticchio, V / Perrino, R / Prati, P / Schiavulli, L / Stöckel, K / Straniero, O / Szücs, T / Trezzi, D / Zavatarelli, S

    Physical review letters

    2018  Volume 121, Issue 17, Page(s) 172701

    Abstract: The ^{22}Ne(p,γ)^{23}Na reaction, part of the neon-sodium cycle of hydrogen burning, may explain the observed anticorrelation between sodium and oxygen abundances in globular cluster stars. Its rate is controlled by a number of low-energy resonances and ... ...

    Abstract The ^{22}Ne(p,γ)^{23}Na reaction, part of the neon-sodium cycle of hydrogen burning, may explain the observed anticorrelation between sodium and oxygen abundances in globular cluster stars. Its rate is controlled by a number of low-energy resonances and a slowly varying nonresonant component. Three new resonances at E_{p}=156.2, 189.5, and 259.7 keV have recently been observed and confirmed. However, significant uncertainty on the reaction rate remains due to the nonresonant process and to two suggested resonances at E_{p}=71 and 105 keV. Here, new ^{22}Ne(p,γ)^{23}Na data with high statistics and low background are reported. Stringent upper limits of 6×10^{-11} and 7×10^{-11}  eV (90% confidence level), respectively, are placed on the two suggested resonances. In addition, the off-resonant S factor has been measured at unprecedented low energy, constraining the contributions from a subthreshold resonance and the direct capture process. As a result, at a temperature of 0.1 GK the error bar of the ^{22}Ne(p,γ)^{23}Na rate is now reduced by 3 orders of magnitude.
    Language English
    Publishing date 2018-11-13
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.121.172701
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 4' 58/153: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

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