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  1. Artikel ; Online: Statistical (n,

    Lewis, R / Couture, A / Liddick, S N / Spyrou, A / Bleuel, D L / Campo, L Crespo / Crider, B P / Dombos, A C / Guttormsen, M / Kawano, T / Larsen, A C / Lewis, A M / Mosby, S / Perdikakis, G / Prokop, C J / Quinn, S J / Renstrøm, T / Siem, S

    The European physical journal. A, Hadrons and nuclei

    2023  Band 59, Heft 3, Seite(n) 42

    Abstract: Neutron-capture cross sections of neutron-rich nuclei are calculated using a Hauser-Feshbach model when direct experimental cross sections cannot be obtained. A number of codes to perform these calculations exist, and each makes different assumptions ... ...

    Abstract Neutron-capture cross sections of neutron-rich nuclei are calculated using a Hauser-Feshbach model when direct experimental cross sections cannot be obtained. A number of codes to perform these calculations exist, and each makes different assumptions about the underlying nuclear physics. We investigated the systematic uncertainty associated with the choice of Hauser-Feshbach code used to calculate the neutron-capture cross section of a short-lived nucleus. The neutron-capture cross section for
    Supplementary information: The online version contains supplementary material available at 10.1140/epja/s10050-023-00920-0.
    Sprache Englisch
    Erscheinungsdatum 2023-03-09
    Erscheinungsland France
    Dokumenttyp Journal Article
    ZDB-ID 1459066-9
    ISSN 1434-601X ; 1434-6001
    ISSN (online) 1434-601X
    ISSN 1434-6001
    DOI 10.1140/epja/s10050-023-00920-0
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  2. Artikel ; Online: First Study of the ^{139}Ba(n,γ)^{140}Ba Reaction to Constrain the Conditions for the Astrophysical i Process.

    Spyrou, A / Mücher, D / Denissenkov, P A / Herwig, F / Good, E C / Balk, G / Berg, H C / Bleuel, D L / Clark, J A / Dembski, C / DeYoung, P A / Greaves, B / Guttormsen, M / Harris, C / Larsen, A C / Liddick, S N / Lyons, S / Markova, M / Mogannam, M J /
    Nikas, S / Owens-Fryar, J / Palmisano-Kyle, A / Perdikakis, G / Pogliano, F / Quintieri, M / Richard, A L / Santiago-Gonzalez, D / Savard, G / Smith, M K / Sweet, A / Tsantiri, A / Wiedeking, M

    Physical review letters

    2024  Band 132, Heft 20, Seite(n) 202701

    Abstract: New astronomical observations point to a nucleosynthesis picture that goes beyond what was accepted until recently. The intermediate "i" process was proposed as a plausible scenario to explain some of the unusual abundance patterns observed in metal-poor ...

    Abstract New astronomical observations point to a nucleosynthesis picture that goes beyond what was accepted until recently. The intermediate "i" process was proposed as a plausible scenario to explain some of the unusual abundance patterns observed in metal-poor stars. The most important nuclear physics properties entering i-process calculations are the neutron-capture cross sections and they are almost exclusively not known experimentally. Here we provide the first experimental constraints on the ^{139}Ba(n,γ)^{140}Ba reaction rate, which is the dominant source of uncertainty for the production of lanthanum, a key indicator of i-process conditions. This is an important step towards identifying the exact astrophysical site of stars carrying the i-process signature.
    Sprache Englisch
    Erscheinungsdatum 2024-06-03
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.132.202701
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  3. Artikel ; Online: Proton Shell Gaps in N=28 Nuclei from the First Complete Spectroscopy Study with FRIB Decay Station Initiator.

    Cox, I / Xu, Z Y / Grzywacz, R / Ong, W-J / Rasco, B C / Kitamura, N / Hoskins, D / Neupane, S / Ruland, T J / Allmond, J M / King, T T / Lubna, R S / Rykaczewski, K P / Schatz, H / Sherrill, B M / Tarasov, O B / Ayangeakaa, A D / Berg, H C / Bleuel, D L /
    Cerizza, G / Christie, J / Chester, A / Davis, J / Dembski, C / Doetsch, A A / Duarte, J G / Estrade, A / Fijałkowska, A / Gray, T J / Good, E C / Haak, K / Hanai, S / Harke, J T / Harris, C / Hermansen, K / Hoff, D E M / Jain, R / Karny, M / Kolos, K / Laminack, A / Liddick, S N / Longfellow, B / Lyons, S / Madurga, M / Mogannam, M J / Nowicki, A / Ogunbeku, T H / Owens-Fryar, G / Rajabali, M M / Richard, A L / Ronning, E K / Rose, G E / Siegl, K / Singh, M / Spyrou, A / Sweet, A / Tsantiri, A / Walters, W B / Yokoyama, R

    Physical review letters

    2024  Band 132, Heft 15, Seite(n) 152503

    Abstract: The first complete measurement of the β-decay strength distribution of _{17}^{45}Cl_{28} was performed at the Facility for Rare Isotope Beams (FRIB) with the FRIB Decay Station Initiator during the second FRIB experiment. The measurement involved the ... ...

    Abstract The first complete measurement of the β-decay strength distribution of _{17}^{45}Cl_{28} was performed at the Facility for Rare Isotope Beams (FRIB) with the FRIB Decay Station Initiator during the second FRIB experiment. The measurement involved the detection of neutrons and γ rays in two focal planes of the FRIB Decay Station Initiator in a single experiment for the first time. This enabled an analytical consistency in extracting the β-decay strength distribution over the large range of excitation energies, including neutron unbound states. We observe a rapid increase in the β-decay strength distribution above the neutron separation energy in _{18}^{45}Ar_{27}. This was interpreted to be caused by the transitioning of neutrons into protons excited across the Z=20 shell gap. The SDPF-MU interaction with reduced shell gap best reproduced the data. The measurement demonstrates a new approach that is sensitive to the proton shell gap in neutron rich nuclei according to SDPF-MU calculations.
    Sprache Englisch
    Erscheinungsdatum 2024-04-29
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.132.152503
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  4. Artikel ; Online: Publisher's Note: Direct Lifetime Measurements of the Excited States in ^{72}Ni [Phys. Rev. Lett. 116, 122502 (2016)].

    Kolos, K / Miller, D / Grzywacz, R / Iwasaki, H / Al-Shudifat, M / Bazin, D / Bingham, C R / Braunroth, T / Cerizza, G / Gade, A / Lemasson, A / Liddick, S N / Madurga, M / Morse, C / Portillo, M / Rajabali, M M / Recchia, F / Riedinger, L L / Voss, P /
    Walters, W B / Weisshaar, D / Whitmore, K / Wimmer, K / Tostevin, J A

    Physical review letters

    2020  Band 124, Heft 20, Seite(n) 209901

    Abstract: This corrects the article DOI: 10.1103/PhysRevLett.116.122502. ...

    Abstract This corrects the article DOI: 10.1103/PhysRevLett.116.122502.
    Sprache Englisch
    Erscheinungsdatum 2020-05-26
    Erscheinungsland United States
    Dokumenttyp Published Erratum
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.124.209901
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  5. Artikel ; Online: β Decay of ^{61}V and its Role in Cooling Accreted Neutron Star Crusts.

    Ong, W-J / Brown, E F / Browne, J / Ahn, S / Childers, K / Crider, B P / Dombos, A C / Gupta, S S / Hitt, G W / Langer, C / Lewis, R / Liddick, S N / Lyons, S / Meisel, Z / Möller, P / Montes, F / Naqvi, F / Pereira, J / Prokop, C /
    Richman, D / Schatz, H / Schmidt, K / Spyrou, A

    Physical review letters

    2020  Band 125, Heft 26, Seite(n) 262701

    Abstract: The interpretation of observations of cooling neutron star crusts in quasipersistent x-ray transients is affected by predictions of the strength of neutrino cooling via crust Urca processes. The strength of crust Urca neutrino cooling depends sensitively ...

    Abstract The interpretation of observations of cooling neutron star crusts in quasipersistent x-ray transients is affected by predictions of the strength of neutrino cooling via crust Urca processes. The strength of crust Urca neutrino cooling depends sensitively on the electron-capture and β-decay ground-state-to-ground-state transition strengths of neutron-rich rare isotopes. Nuclei with a mass number of A=61 are predicted to be among the most abundant in accreted crusts, and the last remaining experimentally undetermined ground-state-to-ground-state transition strength was the β decay of ^{61}V. This Letter reports the first experimental determination of this transition strength, a ground-state branching of 8.1_{-3.1}^{+4.0}%, corresponding to a log ft value of 5.5_{-0.2}^{+0.2}. This result was achieved through the measurement of the β-delayed γ rays using the total absorption spectrometer SuN and the measurement of the β-delayed neutron branch using the neutron long counter system NERO at the National Superconducting Cyclotron Laboratory at Michigan State University. This method helps to mitigate the impact of the pandemonium effect in extremely neutron-rich nuclei on experimental results. The result implies that A=61 nuclei do not provide the strongest cooling in accreted neutron star crusts as expected by some predictions, but that their cooling is still larger compared to most other mass numbers. Only nuclei with mass numbers 31, 33, and 55 are predicted to be cooling more strongly. However, the theoretical predictions for the transition strengths of these nuclei are not consistently accurate enough to draw conclusions on crust cooling. With the experimental approach developed in this work, all relevant transitions are within reach to be studied in the future.
    Sprache Englisch
    Erscheinungsdatum 2020-10-23
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.125.262701
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  6. Artikel ; Online: Mirror-symmetry violation in bound nuclear ground states.

    Hoff, D E M / Rogers, A M / Wang, S M / Bender, P C / Brandenburg, K / Childers, K / Clark, J A / Dombos, A C / Doucet, E R / Jin, S / Lewis, R / Liddick, S N / Lister, C J / Meisel, Z / Morse, C / Nazarewicz, W / Schatz, H / Schmidt, K / Soltesz, D /
    Subedi, S K / Waniganeththi, S

    Nature

    2020  Band 580, Heft 7801, Seite(n) 52–55

    Abstract: Conservation laws are deeply related to any symmetry present in a physical ... ...

    Abstract Conservation laws are deeply related to any symmetry present in a physical system
    Sprache Englisch
    Erscheinungsdatum 2020-04-01
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-020-2123-1
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  7. Artikel ; Online: Publisher's Note: Experimental Neutron Capture Rate Constraint Far from Stability [Phys. Rev. Lett. 116, 242502 (2016)].

    Liddick, S N / Spyrou, A / Crider, B P / Naqvi, F / Larsen, A C / Guttormsen, M / Mumpower, M / Surman, R / Perdikakis, G / Bleuel, D L / Couture, A / Crespo Campo, L / Dombos, A C / Lewis, R / Mosby, S / Nikas, S / Prokop, C J / Renstrom, T / Rubio, B /
    Siem, S / Quinn, S J

    Physical review letters

    2019  Band 122, Heft 12, Seite(n) 129902

    Abstract: This corrects the article DOI: 10.1103/PhysRevLett.116.242502. ...

    Abstract This corrects the article DOI: 10.1103/PhysRevLett.116.242502.
    Sprache Englisch
    Erscheinungsdatum 2019-04-12
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Published Erratum
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.122.129902
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  8. Artikel ; Online: Microsecond Isomer at the N=20 Island of Shape Inversion Observed at FRIB.

    Gray, T J / Allmond, J M / Xu, Z / King, T T / Lubna, R S / Crawford, H L / Tripathi, V / Crider, B P / Grzywacz, R / Liddick, S N / Macchiavelli, A O / Miyagi, T / Poves, A / Andalib, A / Argo, E / Benetti, C / Bhattacharya, S / Campbell, C M / Carpenter, M P /
    Chan, J / Chester, A / Christie, J / Clark, B R / Cox, I / Doetsch, A A / Dopfer, J / Duarte, J G / Fallon, P / Frotscher, A / Gaballah, T / Harke, J T / Heideman, J / Huegen, H / Holt, J D / Jain, R / Kitamura, N / Kolos, K / Kondev, F G / Laminack, A / Longfellow, B / Luitel, S / Madurga, M / Mahajan, R / Mogannam, M J / Morse, C / Neupane, S / Nowicki, A / Ogunbeku, T H / Ong, W-J / Porzio, C / Prokop, C J / Rasco, B C / Ronning, E K / Rubino, E / Ruland, T J / Rykaczewski, K P / Schaedig, L / Seweryniak, D / Siegl, K / Singh, M / Stuchbery, A E / Tabor, S L / Tang, T L / Wheeler, T / Winger, J A / Wood, J L

    Physical review letters

    2023  Band 130, Heft 24, Seite(n) 242501

    Abstract: Excited-state spectroscopy from the first experiment at the Facility for Rare Isotope Beams (FRIB) is reported. A 24(2)-μs isomer was observed with the FRIB Decay Station initiator (FDSi) through a cascade of 224- and 401-keV γ rays in coincidence with ^{ ...

    Abstract Excited-state spectroscopy from the first experiment at the Facility for Rare Isotope Beams (FRIB) is reported. A 24(2)-μs isomer was observed with the FRIB Decay Station initiator (FDSi) through a cascade of 224- and 401-keV γ rays in coincidence with ^{32}Na nuclei. This is the only known microsecond isomer (1  μs≤T_{1/2}<1  ms) in the region. This nucleus is at the heart of the N=20 island of shape inversion and is at the crossroads of the spherical shell-model, deformed shell-model, and ab initio theories. It can be represented as the coupling of a proton hole and neutron particle to ^{32}Mg, ^{32}Mg+π^{-1}+ν^{+1}. This odd-odd coupling and isomer formation provides a sensitive measure of the underlying shape degrees of freedom of ^{32}Mg, where the onset of spherical-to-deformed shape inversion begins with a low-lying deformed 2^{+} state at 885 keV and a low-lying shape-coexisting 0_{2}^{+} state at 1058 keV. We suggest two possible explanations for the 625-keV isomer in ^{32}Na: a 6^{-} spherical shape isomer that decays by E2 or a 0^{+} deformed spin isomer that decays by M2. The present results and calculations are most consistent with the latter, indicating that the low-lying states are dominated by deformation.
    Mesh-Begriff(e) Cell Nucleus ; Heart ; Isotopes ; Neutrons
    Chemische Substanzen Isotopes
    Sprache Englisch
    Erscheinungsdatum 2023-06-30
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.130.242501
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  9. Artikel ; Online: Crossing N=28 Toward the Neutron Drip Line: First Measurement of Half-Lives at FRIB.

    Crawford, H L / Tripathi, V / Allmond, J M / Crider, B P / Grzywacz, R / Liddick, S N / Andalib, A / Argo, E / Benetti, C / Bhattacharya, S / Campbell, C M / Carpenter, M P / Chan, J / Chester, A / Christie, J / Clark, B R / Cox, I / Doetsch, A A / Dopfer, J /
    Duarte, J G / Fallon, P / Frotscher, A / Gaballah, T / Gray, T J / Harke, J T / Heideman, J / Heugen, H / Jain, R / King, T T / Kitamura, N / Kolos, K / Kondev, F G / Laminack, A / Longfellow, B / Lubna, R S / Luitel, S / Madurga, M / Mahajan, R / Mogannam, M J / Morse, C / Neupane, S / Nowicki, A / Ogunbeku, T H / Ong, W-J / Porzio, C / Prokop, C J / Rasco, B C / Ronning, E K / Rubino, E / Ruland, T J / Rykaczewski, K P / Schaedig, L / Seweryniak, D / Siegl, K / Singh, M / Tabor, S L / Tang, T L / Wheeler, T / Winger, J A / Xu, Z

    Physical review letters

    2022  Band 129, Heft 21, Seite(n) 212501

    Abstract: New half-lives for exotic isotopes approaching the neutron drip-line in the vicinity of N∼28 for Z=12-15 were measured at the Facility for Rare Isotope Beams (FRIB) with the FRIB decay station initiator. The first experimental results are compared to the ...

    Abstract New half-lives for exotic isotopes approaching the neutron drip-line in the vicinity of N∼28 for Z=12-15 were measured at the Facility for Rare Isotope Beams (FRIB) with the FRIB decay station initiator. The first experimental results are compared to the latest quasiparticle random phase approximation and shell-model calculations. Overall, the measured half-lives are consistent with the available theoretical descriptions and suggest a well-developed region of deformation below ^{48}Ca in the N=28 isotones. The erosion of the Z=14 subshell closure in Si is experimentally confirmed at N=28, and a reduction in the ^{38}Mg half-life is observed as compared with its isotopic neighbors, which does not seem to be predicted well based on the decay energy and deformation trends. This highlights the need for both additional data in this very exotic region, and for more advanced theoretical efforts.
    Sprache Englisch
    Erscheinungsdatum 2022-10-10
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.129.212501
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  10. Artikel ; Online: Split isobaric analog state in 55Ni: case of strong isospin mixing.

    Tripathi, Vandana / Tabor, S L / Volya, A / Liddick, S N / Bender, P C / Larson, N / Prokop, C / Suchyta, S / Tai, P-L / Vonmoss, J M

    Physical review letters

    2013  Band 111, Heft 26, Seite(n) 262501

    Abstract: Study of β+ decay of the exotic Tz=-3/2 nucleus 55Cu, via delayed γ rays, has revealed a strongly isospin mixed doublet (4599-4579 keV) in 55Ni, which represents the fragmented and previously unknown isobaric analog of the ground state of 55Cu. The ... ...

    Abstract Study of β+ decay of the exotic Tz=-3/2 nucleus 55Cu, via delayed γ rays, has revealed a strongly isospin mixed doublet (4599-4579 keV) in 55Ni, which represents the fragmented and previously unknown isobaric analog of the ground state of 55Cu. The observed small log ft values to both states in the doublet confirm the superallowed Fermi β decay. The near degeneracy of a pair of 3/2- levels in 55Ni results in the strong isospin mixing. The isospin mixing matrix element between the T=3/2 and T=1/2 levels is inferred from the experiment to be 9(1) keV, which agrees well with the matrix element of the charge symmetry breaking shell model Hamiltonian of Ormand and Brown. A precise value of the half-life of 55Cu at 57(3) ms was also obtained.
    Sprache Englisch
    Erscheinungsdatum 2013-12-27
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ZDB-ID 208853-8
    ISSN 1079-7114 ; 0031-9007
    ISSN (online) 1079-7114
    ISSN 0031-9007
    DOI 10.1103/PhysRevLett.111.262501
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