The European Physical Journal A最新文献_第6页

Benchmarking (mathbf {Lambda })NN three-body forces and first predictions for (A=3-5) hypernuclei

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-02-01 DOI: 10.1140/epja/s10050-024-01474-5

Hoai Le, Johann Haidenbauer, Hiroyuki Kamada, Michio Kohno, Ulf-G. Meißner, Kazuya Miyagawa, Andreas Nogga

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Instrumentation for high-field dynamic nuclear polarization and electron paramagnetic resonance spectroscopy

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-29 DOI: 10.1140/epja/s10050-025-01483-y

Thorsten Maly, Timothy J. Keller

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The Felsenkeller shallow-underground laboratory for nuclear astrophysics

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-29 DOI: 10.1140/epja/s10050-025-01490-z

Daniel Bemmerer, Axel Boeltzig, Marcel Grieger, Katharina Gudat, Thomas Hensel, Eliana Masha, Max Osswald, Bruno Poser, Simon Rümmler, Konrad Schmidt, José Luis Taín, Ariel Tarifeño-Saldivia, Steffen Turkat, Anup Yadav, Kai Zuber

{"title":"The Felsenkeller shallow-underground laboratory for nuclear astrophysics","authors":"Daniel Bemmerer, Axel Boeltzig, Marcel Grieger, Katharina Gudat, Thomas Hensel, Eliana Masha, Max Osswald, Bruno Poser, Simon Rümmler, Konrad Schmidt, José Luis Taín, Ariel Tarifeño-Saldivia, Steffen Turkat, Anup Yadav, Kai Zuber","doi":"10.1140/epja/s10050-025-01490-z","DOIUrl":"10.1140/epja/s10050-025-01490-z","url":null,"abstract":"<div>In the Felsenkeller shallow-underground site, protected from cosmic muons by a 45 m thick rock overburden, a research laboratory including a 5 MV Pelletron ion accelerator and a number of radioactivity-measurement setups is located. The laboratory and its installations are described in detail. The background radiation has been studied, finding suppression factors of 40 for cosmic-ray muons, 200 for ambient neutrons, and 100 for the background in germanium (gamma )-ray detectors. Using an additional active muon veto, typically the background is just twice as high as in very deep underground laboratories. The properties of the accelerator including its external and internal ion sources and beam line are given. For the radioactivity counting setup, detection limits in the 10(^{-4}) Bq range have been obtained. Practical aspects for the usage of the laboratory by outside scientific users are discussed.</div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epja/s10050-025-01490-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Some results of 209Bi photoactivation experiment

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-29 DOI: 10.1140/epja/s10050-024-01479-0

M. Krmar, R. Smolović, N. Jovančević, D. Maletić, Y. Teterev, S. Mitrofanov, K. D. Timoshenko, S. I. Alexeev, H. Marukyan, A. Hakobyan

{"title":"Some results of 209Bi photoactivation experiment","authors":"M. Krmar, R. Smolović, N. Jovančević, D. Maletić, Y. Teterev, S. Mitrofanov, K. D. Timoshenko, S. I. Alexeev, H. Marukyan, A. Hakobyan","doi":"10.1140/epja/s10050-024-01479-0","DOIUrl":"10.1140/epja/s10050-024-01479-0","url":null,"abstract":"<div>Photoactivation of a natural bismuth target was performed in bremsstrahlung beams with maximum energies of 40 MeV, 50 MeV and 60 MeV. Several products of (γ,xn) reactions were identified in the gamma spectra and saturation activities and flux averaged sections were calculated for them. The obtained values were compared with the results based on TALYS estimates of the cross sections of the observed reactions. TALYS estimates were calculated for all combinations of photon strength function and level density (a total of 54 of them) with the intention of evaluating which of them shows the best agreement with the experimental results. The minimum and maximum estimates of the saturation activity obtained from the 54 photon SF and LD model combinations differ in most cases by an order of magnitude. The experimental values fall within this range. At 60 MeV, the experimental values of the saturation activity are lower than most TALYS estimates. A similar result is observed at 50 MeV, but to a somewhat lesser extent, while at 40 MeV, approximately the same number of saturation activities obtained from the TALYS cross-sections give both higher and lower estimates compared to the experiment. The flux averaged cross sections calculated using the TENDL estimates are two to three times larger than the experimental ones. By comparing experimental and theoretical values of flux-averaged cross sections for the formation of 206Bi, it was observed that good agreement was shown by those combinations of SF and LD models that are phenomenological in their formulation. No such trend was observed for other bismuth isotopes. There is a significant need to measure the cross sections of nuclear reactions with a higher multiplicity of emitted particles to provide experimental material for further development of models for calculating reaction cross sections.</div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Partial-wave analysis to determine the spin of (Xi (1690)^{-}) and (Xi (1820)^{-}) produced in (overline{p}p) annihilation

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-28 DOI: 10.1140/epja/s10050-025-01492-x

Deepak Pachattu

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Ab initio Bogoliubov many-body perturbation theory: closed-form constraint on the average particle number

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-28 DOI: 10.1140/epja/s10050-024-01480-7

P. Demol, T. Duguet, A. Tichai

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Charged hadron spectra and anisotropic flow from the AMPT model with shear viscous transport dynamics simulations at RHIC

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-27 DOI: 10.1140/epja/s10050-025-01498-5

Yao Zhang

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Pseudoscalar and vector tetraquarks (bb{overline{c}}{overline{c}})

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-27 DOI: 10.1140/epja/s10050-024-01476-3

S. S. Agaev, K. Azizi, H. Sundu

{"title":"Pseudoscalar and vector tetraquarks (bb{overline{c}}{overline{c}})","authors":"S. S. Agaev, K. Azizi, H. Sundu","doi":"10.1140/epja/s10050-024-01476-3","DOIUrl":"10.1140/epja/s10050-024-01476-3","url":null,"abstract":"<div>The pseudoscalar and vector four-quark states (bb{overline{c}}{overline{c}}) are studied in the context of the QCD sum rule method. We model (T_{text { PS}} ) and (T_{text {V}}) as structures built of diquarks ( b^{T}Cgamma _{5}b), ({overline{c}}C{overline{c}}^{T}) and (b^{T}Cgamma _{5}b), ({overline{c}}Cgamma _{mu }gamma _{5}{overline{c}}^{T}), respectively, with C being the charge conjugation matrix. The spectroscopic parameters of the tetraquarks (T_{text {PS}}) and (T_{text {V}}), i.e., their masses and current couplings are calculated using QCD two-point sum rule method. We evaluate the full widths of (T_{text {PS}}) and (T_{text {V}}) by taking into account their kinematically allowed decay channels. In the case of the pseudoscalar particle they are processes (T_{text {PS}} rightarrow B_{c}^{-}B_{c}^{*-}), (B_{c}^{-}B_{c}^{-}(1^{3}P_{0})) and (B_{c}^{*-}B_{c}^{-}(1^{1}P_{1})). The vector state (T_{text {V}}) can dissociate to meson pairs (2 B_{c}^{-}), (2 B_{c}^{*-}) and ( B_{c}^{-}B_{c}^{-}(1^{1}P_{1})). Partial widths of these decays are determined by the strong couplings at relevant tetraquark-meson-meson vertices, which evaluated in the context of the three-point sum rule approach. Predictions obtained for the mass and full width of the pseudoscalar (m =(13.092pm 0.095)~text {GeV}), (Gamma _{text {PS} }=(63.7pm 13.0)~text {MeV}) and vector ({widetilde{m}} =(13.15pm 0.10)~ text {GeV}), (Gamma _{text {V}}=(53.5pm 10.3)~text {MeV}) tetraquarks can be useful for analyses of different four-quark resonances.</div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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A new way to unravel the (^{12})C((alpha ),(gamma ))(^{16})O cross section components using neural networks

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-25 DOI: 10.1140/epja/s10050-024-01478-1

J. G. Duarte, A. Di Leva, R. Buompane, A. Formicola, J. T. Harke, D. Rapagnani, C. Santonastaso, L. Gialanella

{"title":"A new way to unravel the (^{12})C((alpha ),(gamma ))(^{16})O cross section components using neural networks","authors":"J. G. Duarte, A. Di Leva, R. Buompane, A. Formicola, J. T. Harke, D. Rapagnani, C. Santonastaso, L. Gialanella","doi":"10.1140/epja/s10050-024-01478-1","DOIUrl":"10.1140/epja/s10050-024-01478-1","url":null,"abstract":"<div>The (^{12})C((alpha ),(gamma ))(^{16})O reaction rate is crucial in determining the carbon-to-oxygen abundance ratio in stellar nucleosynthesis. Measuring this reaction’s cross section at stellar energies is challenging due to its extremely small value, approximately 10(^{-17}) barn at E(_{mathrm {c.m.}}) = 300 keV. To address this, R-matrix calculations are employed to extrapolate data to lower energies, requiring a comprehensive understanding of each contribution to the cross section. The dominant contributions to the cross section at stellar energies arise from electric dipole (E1) and electric quadrupole (E2) transitions to the ground state of (^{16})O, along with a significant cascade contribution. Traditionally, these contributions have been separated using the (gamma )-ray angular distribution. In this work, we propose a novel technique using the energy distribution of the (^{16})O recoils at the focal plane. This method involves a neural network trained on detailed Monte Carlo simulations of the energy distribution of recoils transported through the recoil mass separator ERNA. This approach enables the simultaneous determination of all three contributions with errors around 10% in the energy range E(_{mathrm {c.m.}}) = 1.0–2.2 MeV. By employing this new technique, we aim to significantly improve the accuracy of determining the cross section of the (^{12})C((alpha ),(gamma ))(^{16})O reaction at astrophysical energies.</div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Determination of photonuclear cross section of 58Co((gamma ,)xp) reaction in the energy region 27–32 MeV via the surrogate ratio method

IF 2.6 3区物理与天体物理

The European Physical Journal A Pub Date : 2025-01-25 DOI: 10.1140/epja/s10050-025-01485-w

Shaima Akbar, M. M. Musthafa, C. V. Midhun, S. V. Suryanarayana, Jyoti Pandey, Bhawna Pandey, A. Pal, P. C. Rout, S. Santra, Antony Joseph, K. C. Jagadeesan, S. Ganesan

{"title":"Determination of photonuclear cross section of 58Co((gamma ,)xp) reaction in the energy region 27–32 MeV via the surrogate ratio method","authors":"Shaima Akbar, M. M. Musthafa, C. V. Midhun, S. V. Suryanarayana, Jyoti Pandey, Bhawna Pandey, A. Pal, P. C. Rout, S. Santra, Antony Joseph, K. C. Jagadeesan, S. Ganesan","doi":"10.1140/epja/s10050-025-01485-w","DOIUrl":"10.1140/epja/s10050-025-01485-w","url":null,"abstract":"<div>The photonuclear reaction cross section of 58Co((gamma ,)xp) reaction has been measured for the first time by employing the surrogate reaction technique. The cross section of the photonuclear reaction is obtained in the energy region 27–32 MeV. The compound nucleus 58(hbox {Co}^{*}) was populated using the transfer reaction 56Fe(6Li,(alpha )) at (hbox {E}_{lab}=) 35.9 MeV. To calculate the surrogate ratio, 61Ni((gamma ),xp) was selected as the reference reaction and the corresponding compound nucleus 61(hbox {Ni}^{*}) was populated using the transfer reaction 59Co(6Li,(alpha )) at (hbox {E}_{lab}=) 40.5 MeV. Reference data taken from the recommended IAEA photonuclear database, which adopted the KAERI data in this case, have been used to determine the desired cross section. Compound nuclear cross section calculations have been done using the statistical nuclear reaction code TALYS 1.96.</div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0