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1. Experimental study of the $$ \gamma p \rightarrow K^{0}\Sigma^{+}$$, $$ \gamma n \rightarrow K^{0} \Lambda$$, and $$ \gamma n \rightarrow K^{0} \Sigma^{0}$$ reactions at the Mainz Microtron

   https://doi.org/10.1140/epja/i2019-12924-x  

   Akondi, C. S.; Bantawa, K.; Manley, D. M.; Abt, S.; Achenbach, P.; Afzal, F.; Aguar-Bartolomé, P.; Ahmed, Z.; Annand, J. R.; Arends, H. J.; et al (November 2019, The European Physical Journal A)

   null (Ed.)

   Abstract. This work measured $$ \mathrm{d}\sigma/\mathrm{d}\Omega$$ d σ / d Ω for neutral kaon photoproduction reactions from threshold up to a c.m. energy of 1855MeV, focussing specifically on the $$ \gamma p\rightarrow K^0\Sigma^+$$ γ p → K 0 Σ + , $$ \gamma n\rightarrow K^0\Lambda$$ γ n → K 0 Λ , and $$ \gamma n\rightarrow K^0 \Sigma^0$$ γ n → K 0 Σ 0 reactions. Our results for $$ \gamma n\rightarrow K^0 \Sigma^0$$ γ n → K 0 Σ 0 are the first-ever measurements for that reaction. These data will provide insight into the properties of $$ N^{\ast}$$ N * resonances and, in particular, will lead to an improved knowledge about those states that couple only weakly to the $$ \pi N$$ π N channel. Integrated cross sections were extracted by fitting the differential cross sections for each reaction as a series of Legendre polynomials and our results are compared with prior experimental results and theoretical predictions. 

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2. Cross sections for the ⁵⁴ Fe(n, n′) ⁵⁴ Fe and ⁵⁴ Fe(n, p′) ⁵⁴ Mn reactions deduced from the detection of de-excitation γ rays

   https://doi.org/10.1051/epjconf/202532905001  

   Hicks, S F; Pecha, R L; Howard, T J; French, A J; Santonil, Z C; Vanhoy, J R; Ramirez, A_P D; Peters, E E; Liu, S H; Prados-Estevez, F M; et al (January 2025, EPJ Web of Conferences)

   Jentschel, M (Ed.)

   γ-ray production cross sections have been deduced for reactions with incident neutrons having energies from 1.5 - 4.7 MeV. Similar measurements were made on a natural Ti sample to establish an absolute normalization. The resulting γ-ray production cross sections are compared to TENDL and TALYS calculations, as well as data from previous measurements. The models are found to describe the production cross sections for mostγrays observed from⁵⁴Mn and⁵⁴Fe rather well. 

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3. Nuclear structure and direct reaction studies in particle-γ coincidence experiments at the FSU John D. Fox superconducting linear accelerator laboratory

   https://doi.org/10.3389/fphy.2024.1511394  

   Spieker, Mark-Christoph; Almaraz-Calderon, Sergio (December 2024, Frontiers in Physics)

   Kay, Benjamin (Ed.)

   Since its foundation in the 1960s, the John D. Fox Superconducting Linear Accelerator Laboratory at Florida State University (FSU) pursued research at the forefront of nuclear science. In this contribution, we present recent highlights from nuclear structure and reaction studies conducted at the John D. Fox Superconducting Linear Accelerator Laboratory, also featuring the general experimental capabilities at the laboratory for particle- $\gamma$coincidence experiments. Specifically, we focus on light-ion induced reactions measured with the Super-Enge Split-Pole Spectrograph (SE-SPS) and the CATRiNA neutron detectors, respectively. Some results obtained with the CeBrA demonstrator for particle- $\gamma$coincidence experiments at the SE-SPS are presented. A highlight from the first experimental campaigns with the combined CLARION2-TRINITY setup, showing that weak reaction channels can be selected, is discussed as well. 

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4. Experimental study of the proton-transfer reaction C + H ₂ ⁺ → CH ⁺ + H and its isotopic variant (D ₂ ⁺ )

   https://doi.org/10.1039/D0CP04810K  

   Hillenbrand, Pierre-Michel; Bowen, Kyle P.; Dayou, Fabrice; Miller, Kenneth A.; de Ruette, Nathalie; Urbain, Xavier; Savin, Daniel W. (December 2020, Physical Chemistry Chemical Physics)

   We report absolute integral cross section (ICS) measurements using a dual-source merged-fast-beams apparatus to study the titular reactions over the relative translational energy range of E r ∼ 0.01–10 eV. We used photodetachment of C − to produce a pure beam of atomic C in the ground electronic 3 P term, with statistically populated fine-structure levels. The H 2 + and D 2 + were formed in an electron impact ionization source, with well known vibrational and rotational distributions. The experimental work is complemented by a theoretical study of the CH 2 + electronic system in the reactant and product channels, which helps to clarify the possible reaction mechanisms underlying the ICS measurements. Our measurements provide evidence that the reactions are barrierless and exoergic. They also indicate the apparent absence of an intermolecular isotope effect, to within the total experimental uncertainties. Capture models, taking into account either the charge-induced dipole interaction potential or the combined charge-quadrupole and charge-induced dipole interaction potentials, produce reaction cross sections that lie a factor of ∼4 above the experimental results. Based on our theoretical study, we hypothesize that the reaction is most likely to proceed adiabatically through the 1 4 A′ and 1 4 A′′ states of CH 2 + via the reaction C( 3 P) + H 2 + ( 2 Σ+g) → CH + ( 3 Π) + H( 2 S). We also hypothesize that at low collision energies only H 2 + ( v ≤ 2) and D 2 + ( v ≤ 3) contribute to the titular reactions, due to the onset of dissociative charge transfer for higher vibrational v levels. Incorporating these assumptions into the capture models brings them into better agreement with the experimental results. Still, for energies ≲0.1 eV where capture models are most relevant, the modified charge-induced dipole model yields reaction cross sections with an incorrect energy dependence and lying ∼10% below the experimental results. The capture cross section obtained from the combined charge-quadrupole and charge-induced dipole model better matches the measured energy dependence but lies ∼30–50% above the experimental results. These findings provide important guidance for future quasiclassical trajectory and quantum mechanical treatments of this reaction. 

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5. The ⁴¹ Ar(n,y) ⁴² Ar reaction

   https://doi.org/10.1051/epjconf/202328401037  

   Sahoo, R. N.; Paul, M.; Köster, U.; Scott, R.; Tessler, M.; Zylstra, A.; Avila, M. L.; Dickerson, C.; Jayatissa, H.; Kohen, M.S.; et al (January 2023, EPJ Web of Conferences)

   Mattoon, C.M.; Vogt, R.; Escher, J.; Thompson, I. (Ed.)

   The cross-section of the thermal neutron capture⁴¹Ar(n,γ)⁴²Ar(t_1/2=32.9 y) reaction was measured by irradiating a⁴⁰Ar sample at the high-flux reactor of Institut Laue-Langevin (ILL) Grenoble, France. The signature of the two-neutron capture has been observed by measuring the growth curve and identifying the 1524.6 keV γ-lines of the shorter-lived⁴²K(12.4 h) β⁻daughter of⁴²Ar. Our preliminary value of the⁴¹Ar(n,γ)⁴²Ar thermal cross section is 240(80) mb at 25.3 meV. For the first time, direct counting of⁴²Ar was performed using the ultra-high sensitivity technique of noble gas accelerator mass spectrometry (NOGAMS) at Argonne National Laboratory, USA. 

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