Thu·Sep 17, 2020Thursday·September 17, 2020

1. 01*

   Measurement of beam asymmetry for ${\pi }^{-}{\Delta }^{++}$ photoproduction on the proton at $E_{\gamma }$=8.5 GeV

   GlueX Collaboration: S. Adhikari🇺🇸 · C. S. Akondi🇺🇸 · A. Ali🇩🇪 · M. Amaryan🇺🇸 · A. Asaturyan🇦🇲 · A. Austregesilo🇺🇸 · Z. Baldwin🇨🇳 · F. Barbosa🇺🇸 · J. Barlow🇺🇸 · E. Barriga🇺🇸 · R. Barsotti🇺🇸 · T. D. Beattie🇨🇦 and 124 other authors

   We report a measurement of the ${\pi }^{-}$ photoproduction beam asymmetry for the reaction $\vec{\gamma }p\to {\pi }^{-}{\Delta }^{++}$ using data from the GlueX experiment in the photon beam energy range 8.2--8.8 GeV. The asymmetry $\Sigma$ is measured as a function of four-momentum transfer $t$ to the ${\Delta }^{++}$ and compared to phenomenological models. We find that $\Sigma$ varies as a function of $t$: negative at smaller values and positive at higher values of $|t|$. The reaction can be described theoretically by $t$-channel particle exchange requiring pseudoscalar, vector, and tensor intermediaries. In particular, this reaction requires charge exchange, allowing us to probe pion exchange and the significance of higher-order corrections to one-pion exchange at low momentum transfer. Constraining production mechanisms of conventional mesons may aid in the search for and study of unconventional mesons. This is the first measurement of the process at this energy.

   nucl-exhep-exPRC(2021)·13 citations
2. 02*

   Imprint of nuclear bubble in nucleon-nucleus diffraction

   V. Choudhary · W. Horiuchi🇯🇵 · M. Kimura🇯🇵 · R. Chatterjee🇮🇳

   Background: The density of most nuclei is constant in the central region and is smoothly decreasing at the surface. A depletion in the central part of the nuclear density can have nuclear structure effects leading to the formation of "bubble" nuclei. However, probing the density profile of the nuclear interior is, in general, very challenging. Purpose: The aim of this paper is to investigate the nuclear bubble structure, with nucleon-nucleus scattering, and quantify the effect that has on the nuclear surface profile. Method: We employed high-energy nucleon-nucleus scattering under the aegis of the Glauber model to analyze various reaction observables, which helps in quantifying the nuclear bubble. The effectiveness of this method is tested on ${}^{28}$Si with harmonic-oscillator (HO) densities, before applying it on even-even $N=14$ isotones, in the $22\le A\le 34$ mass range, with realistic densities obtained from antisymmetrized molecular dynamics (AMD). Results: Elastic scattering differential cross sections and reaction probability for the proton-${}^{28}$Si reaction are calculated using the HO density to design tests for signatures of nuclear bubble structure. We then quantify the degree of bubble structure for $N=14$ isotones with the AMD densities by analyzing their elastic scattering at 325, 550 and 800 MeV incident energies. The present analyses suggest ${}^{22}$O as a candidate for a bubble nucleus, among even-even $N=14$ isotones, in the $22\le A\le 34$ mass range. Conclusion: We have shown that the bubble structure information is imprinted on the nucleon-nucleus elastic scattering differential cross section, especially in the first diffraction peak. Bubble nuclei tend to have a sharper nuclear surface and deformation seems to be a hindrance in their emergence.

   ↳ nucl-thnucl-exPRC(2020)·26 citations
3. 03*

   Production of 177Lu at the IFMIF-DONES Facility

   Javier Praena🇪🇸 · Francisco Garcia-Infantes🇫🇮 · Laura Fernandez-Maza · Fernando Arias de Saavedra · Ignacio Porras🇪🇸

   The International Fusion Materials Irradiation Facility - Demo Oriented NEutron Source (IFMIF-DONES) is a single-sited novel Research Infrastructure for testing, validation and qualification of the materials to be used in a fusion reactor. Recently, IFMIF-DONES has been declared of interest by ESFRI (European Strategy Forum on Research Infrastructures) and its European host city would be Granada (Spain). In spite the first and most important application of IFMIF-DONES related to fusion technology, the unprecedented neutron flux available could be exploited without modifying the routine operation of IFMIF-DONES. Thus, it is already planned an experimental hall for a complementary program with neutrons. Also, a complementary program on the use of the deuteron beam could help IFMIF-DONES to be more sustainable. In the present work, we study radioisotope production with deuterons of 177Lu. The results show the viability of IFMIF-DONES for such production in terms of the needs of a territory of small-medium size. Also the study suggests that new nuclear data at higher deuteron energies are mandatory for an accurate study in this field.

   ↳ physics.ins-detnucl-ex0 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.