Bayar, M., Ren, X. L., & Oset, E. (2015). States of rho D*(D)over-bar* with J=3 within the fixed center approximation to the Faddeev equations. Eur. Phys. J. A, 51(5), 61–9pp.
Abstract: We study the interaction of rho, D* and (D) over bar* with spins aligned using the fixed center approximation to the Faddeev equations. We select a cluster of D*(D) over bar*, which is found to be bound in I = 0 and can be associated to the X(3915), and let the rho meson orbit around the D* and (D) over bar*. In this case we find an I = 1 state with mass around 4340 MeV and narrow width of about 50MeV. We also investigate the case with a cluster of rho D* and let the (D) over bar * orbit around the system of the two states. The rho D* cluster is also found to bind and leads to the D-2*(2460) state. The addition of the extra (D) over bar* produces further binding and we find, with admitted uncertainties, a state of I = 0 around 4000MeV, and a less bound narrow state with I = 1 around 4200 MeV.
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Bertoldo, S., Maggioni, G., Raniero, W., Carraro, C., Riccetto, S., Sgarbossa, F., et al. (2021). New method for the production of thin and stable, segmented n plus contacts in HPGe detectors. Eur. Phys. J. A, 57(6), 177–10pp.
Abstract: The realization of pulsed-laser diffused, thin n+ contacts on high purity germanium (HPGe) and their successful segmentation is described. The contacts have been obtained by a laser-induced diffusion of Sb atoms, deposited by sputtering on Ge surface, and then segmented by means of a photolithographic technique. Three small prototypes of gamma ray detectors have been implemented, using the same n+ contact (laser diffused Sb) but with three different geometries and a B implanted p+ contact. Electrical and detection properties of the prototypes have been characterized, showing low leakage currents and good spectroscopy data with different gamma-ray sources. The stability of the detector performance has also been tested subjecting one of the prototypes to a typical annealing treatment.
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Bizzeti, P. G., Sona, P., Michelagnoli, C., Melon, B., Bazzacco, D., Farnea, E., et al. (2015). Analyzing power of AGATA triple clusters for gamma-ray linear polarization. Eur. Phys. J. A, 51(4), 49–11pp.
Abstract: We have investigated the ability of AGATA triple clusters to measure the linear polarization of gamma rays, exploiting the azimuthal-angle dependence of the Compton scattering differential cross section. To this aim, partially polarized gamma rays have been produced by Coulomb excitation of the first excited state of Pd-104 and Pd-108, which decay to the ground state by emission of gamma rays of 555.8 keV and 433.9 keV, respectively. Pulse-shape analysis and gamma-ray tracking techniques have been used to determine the position and time sequence of the interaction points inside the germanium crystals. Anisotropies in the detection efficiency have been taken into account using 661.6 keV gammas from a Cs-137 radioactive source. We obtain an average analyzing power of 0.451(34) at 433.9 keV and 0.484(24) at 555.8 keV.
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Clement, E., Bracco, A., Gadea, A., & Simpson, J. (2023). Organisation of the AGATA collaboration and physics campaigns. Eur. Phys. J. A, 59(7), 152–5pp.
Abstract: The AGATA spectrometer has a well-established organisational and management structure for its construction and operation. The roles and responsibilities of each of the management committees and their interaction, as well as the scientific organisation is described in this contribution. The organisation of the present campaign, which aims to realise the 4p spectrometer, is presented. General comments on the previous physics campaigns at LNL (2010-2011), GSI (2012-2014) and GANIL (2015-2021) are made.
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Colovic, P. et al, & Gadea, A. (2017). Stretched configuration of states as inferred from gamma-ray angular distributions in Ar-40+Pb-208 neutron transfer reactions. Eur. Phys. J. A, 53(8), 166–6pp.
Abstract: Angular distributions of.-rays for selected transitions in Ar-40,Ar-41,Ar-42 isotopes have been studied with the PRISMA magnetic spectrometer coupled to the CLARA gamma array. These transitions were populated in Ar isotopes reached via neutron transfer in the Ar-40 + Pb-208 reaction. By comparison with the shape of the experimental angular distribution of the known E2 transitions we established more firmly the spin and parity of excited states. In particular, in Ar-41 for the (11/2(-)) state through the (11/2(-)) -> 7/2(-) transition whose structure was discussed in terms of a phonon-fermion coupled state. The comparison with the expected fully aligned spin indicated that a high level of spin alignment has been reached.
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