Wed·Mar 24, 2021Wednesday·March 24, 2021

1. 01*

   Activation cross section data of deuteron induced nuclear reactions on rubidium up to 50 MeV

   Ferenc Tárkányi🇭🇺 · Alex Hermanne🇧🇪 · Ferenc Ditrói🇭🇺 · Sándor Takács🇭🇺 · Anatolij V. Ignatyuk🇷🇺 · Ingo Spahn🇩🇪 · Stephan Spellerberg🇩🇪

   Activation cross sections of the ${}^{nat}$Rb (d,xn)${}^{87m,85m,85g,83,82}$Sr, ${}^{nat}$Rb(d,x)${}^{86,84,83,82m}$Rb and ${}^{nat}$Rb(d,x)${}^{85m}$Kr nuclear reactions have been measured for the first time through an activation method combining the stacked foil irradiation technique and gamma-ray spectrometry. The provided cross sections from the present investigation are all new, in such a way contribute to the completeness of the experimental database. The experimental cross sections were compared with the theoretical prediction in the TENDL-2019 TALYS based library and with our calculation using ALICE-D and EMPIRE-D model codes in order the improve their predictivity. Thick target production yields were calculated form the new cross sections for all investigated radioisotopes. Practical applications of the results are shortly discussed.

   nucl-exEPJA(2021)·4 citations
2. 02*

   Accessing weak neutral-current coupling $g_{AA}^{eq}$ using positron and electron beams at Jefferson Lab

   Xiaochao Zheng🇺🇸 · Jens Erler🇩🇪 · Qishan Liu🇩🇪 · Huber Spiesberger🇩🇪

   Low-energy neutral-current couplings arising in the Standard Model of electroweak interactions can be constrained in lepton scattering off hydrogen or a nuclear fixed target. Recent polarized electron scattering experiments at Jefferson Lab (JLab) have improved the precision in the parity-violating types of effective couplings. On the other hand, the only known way to access the parity-conserving counterparts is to compare scattering cross sections between a lepton and an anti-lepton beam. We review the current knowledge of both types of couplings and how to constrain them. We also present exploratory calculations for a possible measurement of $g_{AA}^{eq}$ using the planned SoLID spectrometer combined with a possible positron beam at JLab.

   nucl-exhep-phEPJA(2021)·18 citations
3. 03*

   Beam charge asymmetries for deeply virtual Compton scattering off the proton

   V. Burkert · L. Elouadrhiri · F.-X. Girod · S. Niccolai · E.Voutier · A. Afanasev · L. Barion · M. Battaglieri · J.C. Bernauer · A. Bianconi · R. Capobianco · M. Caudron and 48 other authors

   The unpolarized and polarized Beam Char\-ge Asymmetries (BCAs) of the $\text{vv}{e}^{\pm }p\to e^{\pm }p\gamma$ process off unpolarized hydrogen are discussed. The measurement of BCAs with the CLAS12 spectrometer at the Thomas Jefferson National Accelerator Facility, using polarized positron and electron beams at 10.6 GeV is investigated. This experimental configuration allows to measure azimuthal and $t$-dependences of the unpolarized and polarized BCAs over a large $(x_B,Q^2)$ phase space, providing a direct access to the real part of the Compton Form Factor (CFF) $\mathcal{H}$. Additionally, these measurements confront the Bethe-Heitler dominance hypothesis and eventual effects beyond leading twist. The impact of potential positron beam data on the determination of CFFs is also investigated within a local fitting approach of experimental observables. Positron data are shown to strongly reduce correlations between CFFs and consequently improve significantly the determination of $\Re \mathrm{e}[\mathcal{H}]$.

   nucl-exhep-exEPJA(2021)·27 citations
4. 04*

   Cross sections of solar neutrino capture by 127I nuclei and Gamow Teller resonances

   Yu.S. Lutostansky🇷🇺 · A.N. Fazliakhmetov🇷🇺 · G.A. Koroteev🇷🇺 · N.V. Klochkova🇷🇺 · A.P. Osipenko🇷🇺 · V.N. Tikhonov🇷🇺

   Solar neutrino capture cross-section by 127I nucleus has been studied with taking into account the influence of the resonance structure of the nuclear strength function S(E). Three types of isobaric resonances: giant Gamow-Teller, analog resonance and low-lying Gamow-Teller pigmy resonances has been investigated on the framework of self-consistent theory of finite Fermi systems. The calculations have been performed considering the resonance structure of the charge-exchange strength function S(E). We analyze the effect of each resonance on the energy dependence of the cross-section. It has been shown that all high-lying resonances should be considered. Neutron emission process for high energy nuclear excitation leads to formation 126Xe isotope. We evaluate contribution from various sources of solar neutrinos to the 126Xe/127Xe isotopes ratio formed by energetic neutrinos. 126Xe/127Xe isotope ratio could be an indicator of high-energy boron neutrinos in the solar spectrum. We also discuss the uncertainties in the often used Fermi-functions calculations.

   ↳ nucl-thnucl-ex3 citations
5. 05*

   Plant efficiency: a sensitivity analysis of the capacity factor for fusion power plants with high recirculated power

   Ruward A. Mulder🇳🇱 · Yeshambel Melese🇳🇱 · Niek Lopes Cardozo🇳🇱

   The plant efficiency of a nuclear fusion power plant is considered. During nominal operation, the plant efficiency is determined by the thermodynamic efficiency and the recirculated power fraction. However, on average the reactor operates below the nominal power, even when the long shutdown periods for large maintenance are left outside the averaging. Hence, next to the recirculated power fraction, the capacity factor must be factored in. An expression for the plant efficiency which incorporates both factors is given. It is shown that the combination of high recirculated power fraction and a low capacity factor results in poor plant efficiency. This is due to the fact that in a fusion reactor the recirculated power remains high if it runs at reduced output power. It is argued that, at least for a first generation of power plants, this combination is likely to occur. Worked out example calculations are given for the models of the Power Plant Conceptual Study. Finally, the impact on the competitiveness of fusion on the energy market is discussed. This analysis stresses the importance of the development of plant designs with low recirculated power fraction.

   ↳ physics.soc-phnucl-exNucl.Fusion(2021)·0 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.