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  1. Article ; Online: Proton-Capture Rates on Carbon Isotopes and Their Impact on the Astrophysical ^{12}C/^{13}C Ratio.

    Skowronski, J / Boeltzig, A / Ciani, G F / Csedreki, L / Piatti, D / Aliotta, M / Ananna, C / Barile, F / Bemmerer, D / Best, A / Broggini, C / Bruno, C G / Caciolli, A / Campostrini, M / Cavanna, F / Colombetti, P / Compagnucci, A / Corvisiero, P / Davinson, T /
    Depalo, R / Di Leva, A / Elekes, Z / Ferraro, F / Formicola, A / Fülöp, Zs / Gervino, G / Gesuè, R M / Guglielmetti, A / Gustavino, C / Gyürky, Gy / Imbriani, G / Junker, M / Lugaro, M / Marigo, P / Masha, E / Menegazzo, R / Paticchio, V / Perrino, R / Prati, P / Rapagnani, D / Rigato, V / Schiavulli, L / Sidhu, R S / Straniero, O / Szücs, T / Zavatarelli, S

    Physical review letters

    2023  Volume 131, Issue 16, Page(s) 162701

    Abstract: The ^{12}C/^{13}C ratio is a significant indicator of nucleosynthesis and mixing processes during hydrogen burning in stars. Its value mainly depends on the relative rates of the ^{12}C(p,γ)^{13}N and ^{13}C(p,γ)^{14}N reactions. Both reactions have been ...

    Abstract The ^{12}C/^{13}C ratio is a significant indicator of nucleosynthesis and mixing processes during hydrogen burning in stars. Its value mainly depends on the relative rates of the ^{12}C(p,γ)^{13}N and ^{13}C(p,γ)^{14}N reactions. Both reactions have been studied at the Laboratory for Underground Nuclear Astrophysics (LUNA) in Italy down to the lowest energies to date (E_{c.m.}=60  keV) reaching for the first time the high energy tail of hydrogen burning in the shell of giant stars. Our cross sections, obtained with both prompt γ-ray detection and activation measurements, are the most precise to date with overall systematic uncertainties of 7%-8%. Compared with most of the literature, our results are systematically lower, by 25% for the ^{12}C(p,γ)^{13}N reaction and by 30% for ^{13}C(p,γ)^{14}N. We provide the most precise value up to now of 3.6±0.4 in the 20-140 MK range for the lowest possible ^{12}C/^{13}C ratio that can be produced during H burning in giant stars.
    Language English
    Publishing date 2023-11-05
    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.131.162701
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Characterization of Large GEM Module for the Tracker at Jlab Hall A

    Mammoliti F. / Bellin V. / Cisbani E. / Librizzi F. / Musico P. / Noto F. / Perrino R. / Re L. / Sutera M.C.

    EPJ Web of Conferences, Vol 96, p

    2015  Volume 01023

    Abstract: A new Large-Acceptance Forward Angle Spectrometer (Super BigBite) is under development at JLab/Hall A for the upcoming experiments in Hall A at Jefferson Lab where a longitudinally polarized electron beam of 11 GeV is now available. This beam, combined ... ...

    Abstract A new Large-Acceptance Forward Angle Spectrometer (Super BigBite) is under development at JLab/Hall A for the upcoming experiments in Hall A at Jefferson Lab where a longitudinally polarized electron beam of 11 GeV is now available. This beam, combined with innovative polarized targets will provided luminosity up to 1039/(s·cm2) opening exciting opportunities to investigate unexplored aspects of the inner structure of the nucleon. The tracker of this new apparatus is based on the Gas Electron Multiplier (GEM) technology, which has been chosen to optimize cost/performance, position resolution and to meet the high hit rate (>1 MHz/cm2). The first GEM detector modules, designed and built by the INFN Collaboration JLAB12, were tested at the DESY test beam facility in Hamburg, by using an electron beam with energy ranging from 2.0 to 6.0 GeV. In particular, three 40x50 cm2 GEM chambers were equipped with a new implementation of the APV25 readout chip. Measurements were performed at different impact points and angles between the electron beam and the plane of the GEM chambers, with one large chamber in a solenoid magnetic field up to 500 Gauss. In this paper we present the technical features of the tracker and comment on the presently achieved performance.
    Keywords Science ; Q ; Physics ; QC1-999
    Language English
    Publishing date 2015-01-01T00:00:00Z
    Publisher EDP Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Test of the GEM Front Tracker for the SBS Spectrometer at Jefferson Lab

    Mammoliti F. / Bellini V. / Cisbani E. / Librizzi F. / Musico P. / Noto F. / Perrino R. / Sutera M.C.

    EPJ Web of Conferences, Vol 72, p

    2014  Volume 00015

    Abstract: A new Large-Acceptance Forward Angle Spectrometer (Super BigBite) is under development at JLab/Hall A to optimally exploit the exciting opportunities offered by the 12 GeV upgrade of the electron beam. The tracker of this new apparatus is based on the Gas ...

    Abstract A new Large-Acceptance Forward Angle Spectrometer (Super BigBite) is under development at JLab/Hall A to optimally exploit the exciting opportunities offered by the 12 GeV upgrade of the electron beam. The tracker of this new apparatus is based on the Gas Electron Multiplier (GEM) technology, which has been chosen to optimize cost/performance, position resolution and to meet the high hit rate (>1 MHz/cm2). The first GEM detector modules, designed and built by the INFN Collaboration JLAB12, were tested at the DESY test beam facility in Hamburg, by using an electron beam with energy ranging from 2.0 to 6.0 GeV. In particular, two 40x50 cm2 and one 10x10 cm2 GEM chambers were equipped with a new implementation of the APV25 readout chip. Measurements were performed at different impact points and angles between the electron beam and the plane of the GEM chambers, with one large chamber in a solenoid magnetic field up to 500 Gauss. In this report we present the technical characteristics of the detector and comment on the presently achieved performance.
    Keywords Physics ; QC1-999 ; Science ; Q
    Language English
    Publishing date 2014-05-01T00:00:00Z
    Publisher EDP Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. 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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  5. 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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  6. Article ; Online: Measurement of the Charge-Averaged Elastic Lepton-Proton Scattering Cross Section by the OLYMPUS Experiment.

    Bernauer, J C / Schmidt, A / Henderson, B S / Ice, L D / Khaneft, D / O'Connor, C / Russell, R / Akopov, N / Alarcon, R / Ates, O / Avetisyan, A / Beck, R / Belostotski, S / Bessuille, J / Brinker, F / Calarco, J R / Carassiti, V / Cisbani, E / Ciullo, G /
    Contalbrigo, M / De Leo, R / Diefenbach, J / Donnelly, T W / Dow, K / Elbakian, G / Eversheim, P D / Frullani, S / Funke, Ch / Gavrilov, G / Gläser, B / Görrissen, N / Hasell, D K / Hauschildt, J / Hoffmeister, Ph / Holler, Y / Ihloff, E / Izotov, A / Kaiser, R / Karyan, G / Kelsey, J / Kiselev, A / Klassen, P / Krivshich, A / Kohl, M / Lehmann, I / Lenisa, P / Lenz, D / Lumsden, S / Ma, Y / Maas, F / Marukyan, H / Miklukho, O / Milner, R G / Movsisyan, A / Murray, M / Naryshkin, Y / Perez Benito, R / Perrino, R / Redwine, R P / Rodríguez Piñeiro, D / Rosner, G / Schneekloth, U / Seitz, B / Statera, M / Thiel, A / Vardanyan, H / Veretennikov, D / Vidal, C / Winnebeck, A / Yeganov, V

    Physical review letters

    2021  Volume 126, Issue 16, Page(s) 162501

    Abstract: We report the first measurement of the average of the electron-proton and positron-proton elastic scattering cross sections. This lepton charge-averaged cross section is insensitive to the leading effects of hard two-photon exchange, giving more robust ... ...

    Abstract We report the first measurement of the average of the electron-proton and positron-proton elastic scattering cross sections. This lepton charge-averaged cross section is insensitive to the leading effects of hard two-photon exchange, giving more robust access to the proton's electromagnetic form factors. The cross section was extracted from data taken by the OLYMPUS experiment at DESY, in which alternating stored electron and positron beams were scattered from a windowless gaseous hydrogen target. Elastic scattering events were identified from the coincident detection of the scattered lepton and recoil proton in a large-acceptance toroidal spectrometer. The luminosity was determined from the rates of Møller, Bhabha, and elastic scattering in forward electromagnetic calorimeters. The data provide some selectivity between existing form factor global fits and will provide valuable constraints to future fits.
    Language English
    Publishing date 2021-05-07
    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.126.162501
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Coincidence resolution time of two small scintillators coupled to high quantum-efficiency photomultipliers in a PET-like system

    Galetta G. / De Leo R. / Garibaldi F. / Grodzicka M. / Lagamba L. / Loddo F. / Masiello G. / Nappi E. / Perrino R. / Ranieri A. / Szczęśniak T.

    EPJ Web of Conferences, Vol 66, p

    2014  Volume 10010

    Abstract: The lower limit of the time resolution for a positron emission tomography (PET) system has been measured for two scintillator types, LYSO:Ce and LuAG:Pr. Small dimension crystals and ultra bi-alkali phototubes have been used in order to increase the ... ...

    Abstract The lower limit of the time resolution for a positron emission tomography (PET) system has been measured for two scintillator types, LYSO:Ce and LuAG:Pr. Small dimension crystals and ultra bi-alkali phototubes have been used in order to increase the detected scintillation photons. Good timing resolutions of 118 ps and 223 ps FWHM have been obtained for two LYSO and two LuAG, respectively, exposed to a 22Na source.
    Keywords Physics ; QC1-999 ; Science ; Q
    Language English
    Publishing date 2014-03-01T00:00:00Z
    Publisher EDP Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Time and charge characterization of Hamamatsu Photonics silicon photomultipliers

    Galetta G. / Ciciriello F. / Corsi F. / De Leo R. / Garibaldi F. / Lagamba L. / Licciulli F. / Loddo F. / Marzocca C. / Nappi E. / Perrino R. / Ranieri A.

    EPJ Web of Conferences, Vol 66, p

    2014  Volume 11028

    Abstract: Two Hamamatsu Photonics silicon photomultipliers (SiPM) with same cell size 50×50 µm2 and different sensitive area (1×1 mm2 vs. 3×3 mm2) have been characterized in charge and time by means of a 409 nm pico-laser. The time resolution was studied for the ... ...

    Abstract Two Hamamatsu Photonics silicon photomultipliers (SiPM) with same cell size 50×50 µm2 and different sensitive area (1×1 mm2 vs. 3×3 mm2) have been characterized in charge and time by means of a 409 nm pico-laser. The time resolution was studied for the detection of few photoelectrons. The results obtained are relevant for the employment of SiPM in ring imaging Cherenkov detectors (RICH).
    Keywords Physics ; QC1-999 ; Science ; Q
    Language English
    Publishing date 2014-03-01T00:00:00Z
    Publisher EDP Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. 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

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  10. Article ; Online: Hard Two-Photon Contribution to Elastic Lepton-Proton Scattering Determined by the OLYMPUS Experiment.

    Henderson, B S / Ice, L D / Khaneft, D / O'Connor, C / Russell, R / Schmidt, A / Bernauer, J C / Kohl, M / Akopov, N / Alarcon, R / Ates, O / Avetisyan, A / Beck, R / Belostotski, S / Bessuille, J / Brinker, F / Calarco, J R / Carassiti, V / Cisbani, E /
    Ciullo, G / Contalbrigo, M / De Leo, R / Diefenbach, J / Donnelly, T W / Dow, K / Elbakian, G / Eversheim, P D / Frullani, S / Funke, Ch / Gavrilov, G / Gläser, B / Görrissen, N / Hasell, D K / Hauschildt, J / Hoffmeister, Ph / Holler, Y / Ihloff, E / Izotov, A / Kaiser, R / Karyan, G / Kelsey, J / Kiselev, A / Klassen, P / Krivshich, A / Lehmann, I / Lenisa, P / Lenz, D / Lumsden, S / Ma, Y / Maas, F / Marukyan, H / Miklukho, O / Milner, R G / Movsisyan, A / Murray, M / Naryshkin, Y / Perez Benito, R / Perrino, R / Redwine, R P / Rodríguez Piñeiro, D / Rosner, G / Schneekloth, U / Seitz, B / Statera, M / Thiel, A / Vardanyan, H / Veretennikov, D / Vidal, C / Winnebeck, A / Yeganov, V

    Physical review letters

    2017  Volume 118, Issue 9, Page(s) 92501

    Abstract: The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R_{2γ}, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS ... ...

    Abstract The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R_{2γ}, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY. A toroidal magnetic spectrometer instrumented with drift chambers and time-of-flight scintillators detected elastically scattered leptons in coincidence with recoiling protons over a scattering angle range of ≈20° to 80°. The relative luminosity between the two beam species was monitored using tracking telescopes of interleaved gas electron multiplier and multiwire proportional chamber detectors at 12°, as well as symmetric Møller or Bhabha calorimeters at 1.29°. A total integrated luminosity of 4.5  fb^{-1} was collected. In the extraction of R_{2γ}, radiative effects were taken into account using a Monte Carlo generator to simulate the convolutions of internal bremsstrahlung with experiment-specific conditions such as detector acceptance and reconstruction efficiency. The resulting values of R_{2γ}, presented here for a wide range of virtual photon polarization 0.456<ε<0.978, are smaller than some hadronic two-photon exchange calculations predict, but are in reasonable agreement with a subtracted dispersion model and a phenomenological fit to the form factor data.
    Language English
    Publishing date 2017-03-03
    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.118.092501
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