Jido, D., Oset, E., & Sekihara, T. (2011). Kaon-induced Lambda(1405) production on a deuteron target at DAFNE. Eur. Phys. J. A, 47(3), 42–7pp.
Abstract: The K-- induced production of.(1405) in the K(-)d -> pi Sigma n reaction is investigated having in mind the conditions of the DAFNE facility at Frascati where kaons are obtained from the decay of slow-moving phi mesons. We find that the K(-)d -> Lambda(1405)n process favors the production of Lambda(1405) initiated by the K(-)p channel, which gives largest weight to the higher mass Lambda(1405) appearing at 1420MeV in chiral theories. We find that the fastest kaons from the decay of the phi are well suited to see this resonance, particularly if one selects forward going neutrons in the center of mass, which reduce the contribution of single scattering and make the double scattering dominate where the signal of the resonance appears clearer.
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Jido, D., Oset, E., & Sekihara, T. (2013). The K(-)d -> pi Sigma n reaction revisited. Eur. Phys. J. A, 49(8), 95–11pp.
Abstract: The appearance of some papers dealing with the K(-)d -> pi Sigma n reaction, with some discrepancies in the results and a proposal to measure the reaction at forward n angles at J-PARC justifies to retake the theoretical study of this reaction. We do this in the present paper showing results using the Watson approach and the truncated Faddeev approach. We argue that the Watson approach is more suitable to study the reaction because it takes into account the potential energy of the nucleons forming the deuteron, which is neglected in the truncated Faddeev approach. The paper shows the strength and limitations of both approaches and we perform calculations using four different approximations. Comparison of the results shows that the truncated Faddeev approach produces a strong asymmetry between the energy of the two nucleons of the deuteron, while in the Watson approach this energy is equally shared. From the experimental point of view the results are very valuable since they show that the different approximations share the feature that the peak of the pi Sigma mass distribution is drastically shifted in the presence of the Lambda(1405). Additionally, we also show that in the angle-integrated cross section the threshold cusp effects are basically washed away and all approximations show a clear shape of the Lambda(1405). In this sense, measurements of all these magnitudes in different K- energies are bound to bring new information that sheds new light on the properties and nature of the Lambda(1405) resonance.
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Kaskulov, M., Hernandez, E., & Oset, E. (2010). On the background in the gamma p -> omega(pi(0)gamma)p reaction and mixed event simulation. Eur. Phys. J. A, 46(2), 223–230.
Abstract: In this paper we evaluate sources of background of the gamma p -> omega p reaction, with the omega detected through its pi(0)gamma decay channel, to compare with the experiment carried out at ELSA. We find background from gamma p -> pi(0)pi(0)p followed by decay of a pi(0) into two gamma, recombining one pi(0) and one gamma, and from the gamma p -> pi(0)eta p reaction with subsequent decay of the eta into two photons. This background accounts for the data at pi(0)gamma invariant masses beyond 700 MeV, but strength is missing at lower invariant masses which was attributed to photon misidentification events, which we simulate to get a good reproduction of the experimental background. Once this is done, we perform an event mixing simulation to reproduce the calculated background and we find that the method provides a good description of the background. A closer look reveals this is accidental. We show that the mixed event generated background in the region of the omega mass and beyond is completely tied to the events at low pi(0)gamma invariant masses where the d sigma/dM(pi 0 gamma) distribution is much larger. This has as a consequence that the mixed event method produces the same background at high invariant masses independently of the actual background in that region, as a consequence of which, the method is unsuited to give the background at energies around the peak of the omega and beyond.
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Kim, Y. H. et al, & Perez-Vidal, R. M. (2017). Prompt-delayed gamma-ray spectroscopy with AGATA, EXOGAM and VAMOS plus. Eur. Phys. J. A, 53(8), 162–8pp.
Abstract: A new experimental setup to measure prompt-delayed gamma-ray coincidences from isotopically identified fission fragments, over a wide time range of 100 ns-200 μs, is presented. The fission fragments were isotopically identified, on an event-by-event basis, using the VAMOS++ large acceptance spectrometer. The prompt gamma rays emitted at the target position and corresponding delayed gamma rays emitted at the focal plane of the spectrometer were detected using, respectively, thirty two crystals of the AGATA gamma-ray tracking array and seven EXOGAM HPGe Clover detectors. Fission fragments produced in fusion and transfer-induced fission reactions, using a U-238 beam at an energy of 6.2MeV/u impinging on a Be-9 target, were used to characterize and qualify the performance of the detection system.
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Kucuk, L. et al, Orrigo, S. E. A., Montaner-Piza, A., Rubio, B., Gelletly, W., Algora, A., et al. (2017). Half-life determination of T-z =-1 and T-z =-1/2 proton-rich nuclei and the beta decay of Zn-58. Eur. Phys. J. A, 53(6), 134–10pp.
Abstract: We have measured the beta-decay half-lives of 16 neutron-deficient nuclei with T-z = -1/2 and -1, ranging from chromium to germanium. They were produced in an experiment carried out at GANIL and optimized for the production of Zn-58, for which in addition we present the decay scheme and absolute Fermi and Gamow-Teller transition strengths. Since all of these nuclei lie on the rp-process pathway, the T-1/2 values are important ingredients for the rp-process reaction flow calculations and for models of X-ray bursters.
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Labiche, M., Ljungvall, J., Crespi, F. C. L., Chen, S., Bordes, J., Goasduff, A., et al. (2023). Simulation of the AGATA spectrometer and coupling with ancillary detectors. Eur. Phys. J. A, 59(7), 158–12pp.
Abstract: The design study of the AGATA array began with the development of the AGATA simulation code using GEANT4. The latter played a key part in the final design of the array and provided a cost effective solution for the early development of the tracking algorithm. The code has since been maintained and developed by the collaboration to provide more realistic simulations, with reaction chambers, ancillary detectors and surrounding mechanical structures completing the entire setup.
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n_TOF Collaboration(Lederer-Woods, C. et al), Domingo-Pardo, C., Tain, J. L., & Tarifeño-Saldivia, A. (2022). Ge-74(n, gamma) cross section below 70 keV measured at n_TOF CERN. Eur. Phys. J. A, 58(12), 239–9pp.
Abstract: Neutron capture reaction cross sections on Ge-74 are of importance to determine Ge-74 production during the astrophysical slow neutron capture process. We present new resonance data on Ge-74(n, gamma ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.
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Lewandowski, L., Reiter, P., Birkenbach, B., Bruyneel, B., Clemente, E., Eberth, J., et al. (2019). Pulse-Shape Analysis and position resolution in highly segmented HPGe AGATA detectors. Eur. Phys. J. A, 55(5), 81–13pp.
Abstract: The performance of the Pulse-Shape Analysis (PSA) in AGATA HPGe detectors was investigated and improved employing a -ray source measurement based on e+e- annihilation radiation after decays of Na-22 by + decay. The first interaction positions of the two 511keV rays were determined and the connecting line of these two positions was compared to the known source position as a measure for the PSA performance. The position resolution and its dependence on the PSA parameters were investigated by varying most relevant input quantities: the charge carrier mobility of the holes, the response of the employed measuring electronics especially the preamplifier rise time. The relative statistical weight of charge signals and transient signals was scrutinized. The optimal distance metric of the grid-search algorithm and its impact on the position resolution were determined.
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Liang, W. H., Uchino, T., Xiao, C. W., & Oset, E. (2015). Baryon states with open charm in the extended local hidden gauge approach. Eur. Phys. J. A, 51(2), 16–14pp.
Abstract: In this paper we examine the interaction of DN and D* N states, together with their coupled channels, by using an extension of the local hidden gauge formalism from the light meson sector, which is based on heavy quark spin symmetry. The scheme is based on the use of the impulse approximation at the quark level, with the heavy quarks acting as spectators, which occurs for the dominant terms where there is the exchange of a light meson. The pion exchange and the Weinberg-Tomozawa interactions are generalized and with this dynamics we look for states generated from the interaction, with a unitary coupled channels approach that mixes the pseudoscalar-baryon and vector-baryon states. We find two states with nearly zero width, which are associated to the I > (c) (2595) and I > (c) (2625). The lower state, with J (P) = 1/2(-), couples to DN and D* N, and the second one, with J (P) = 3/2(-), to D* N. In addition to these two I > (c) states, we find four more states with I = 0, one of them nearly degenerate in two states of J (P) = 1/2, 3/2. Furthermore we find three states in I = 1, two of them degenerate in J = 1/2, 3/2.
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Liang, W. H., Molina, R., & Oset, E. (2010). Radiative open charm decay of the Y(3940), Z(3930), X(4160) resonances. Eur. Phys. J. A, 44(3), 479–486.
Abstract: We determine the radiative decay amplitudes for the decay into D* and (D) over bar gamma, or (D) over bar gamma(s)* and s. of some of the charmonium- like states classified as X, Y, Z resonances, plus some other hidden charm states which are dynamically generated from the interaction of vector mesons with charm. The mass distributions as a function of the (D) over bar gamma or (D) over bar (s)gamma. invariant mass show a peculiar behavior as a consequence of the D* (D) over bar gamma* nature of these states. The experimental search of these magnitudes can shed light on the nature of these states.
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