NILBERTO HEDER MEDINA

NILBERTO HEDER MEDINA

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Elastic scattering angular distribution for the 18O + 48Ti collision at 275 MeV within the NUMEN project
2024 - BRISCHETTO, G.A.; SGOUROS, O.; CARBONE, D.; CAPPUZZELLO, F.; CAVALLARO, M.; LUBIAN, J.; DE GREGORIO, G.; AGODI, C.; CALVO, D.; CHAVEZ LOMELI, E.R.; CIRALDO, I.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FISICHELLA, M.; GARGANO, A.; GUAZZELLI, M.A.; HACISALIHOGLU, A.; LINARES, R.; MEDINA, N.H.; MORALLES, M.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; SOUKERAS, V.; SOULIOTIS, G.; SPATAFORA, A.; TORRESI, D.; YILDIRIM, A.; ZAGATTO, V.A.B.
In the context of the NUMEN project, the 18O + 48Ti collision at 275 MeV incident energy was studied for the first time. In the adopted multichannel approach, the elastic scattering was measured in order to deduce the initial state interaction and the corresponding optical potential. The angular distribution of elastic scattering was determined across a wide range of scattering angles.
Response of G-NUMEN LaBr3(Ce) detectors to high counting rates
2023 - GANDOLFO, ELISA M.; OLIVEIRA, JOSE R.B.; CAMPAJOLA, LUIGI; PIERROUTSAKOU, DIMITRA; BOIANO, ALFONSO; AGODI, CLEMENTINA; CAPPUZZUELLO, FRANCESCO; CARBONE, DIANA; CAVALLARO, MANUELA; CIRALDO, IRENE; CALVO, DANIELA; DELAUNAY, FRANCK; EKE, CANEL; LONGHITANO, FABIO; MEDINA, NILBERTO; MORALLES, MAURICIO; SARTIRANA, DIEGO; SHARMA, VIJAY R.; SAPATAFORA, ALESSANDRO; TOUFEN, DENNIS; FINOCCHIARO, PAOLO
The G-NUMEN array is the future gamma spectrometer of the NUMEN experiment (nuclear matrix element for neutrinoless double beta decay), to be installed around the object point of the MAGNEX magnetic spectrometer at the INFN-LNS laboratory. This project aims to explore doublecharge exchange (DCE) reactions in order to obtain crucial information about neutrinoless double beta decay (0νββ). The primary objective of the G-NUMEN array is to detect the gamma rays emitted from the de-excitation of the excited states that are populated via DCE reactions with a good energy resolution and detection efficiency, amidst a background composed of the transitions from competing reaction channels with far higher cross sections. To achieve this, G-NUMEN signals will be processed in coincidence with those generated by the detection of reaction ejectiles by the MAGNEX focal plane detector (FPD). Under the expected experimental conditions, G-NUMEN detectors will operate at high counting rates, of the order of hundreds of kHz per detector, while maintaining excellent energy and timing resolutions. The complete array will consist of over 100 LaBr3 (Ce) scintillators. Initial tests were conducted on the first detectors of the array, allowing for the determination of their performance at high rates.
Multichannel experimental and theoretical approach to the 12C(18O, 18F)12B single-charge-exchange reaction at 275 MeV
2023 - SPATAFORA, A.; CARBONE, D.; CAPPUZZELLO, F.; CAVALLARO, M.; ACOSTA, L.; AGODI, C.; AMADOR-VALENZUELA, P.; BORELLO-LEWIN, T.; BRISCHETTO, G.A.; CALABRESE, S.; CALVO, D.; CAPIROSSI, V.; CHAVEZ LOMELI, E.R.; CIRALDO, I.; DE GREGORIO, G.; DELAUNAY, F.; DJAPO, H.; EKE, C.; FINOCCHIARO, P.; FIRAT, S.; FISICHELLA, M.; FOTI, A.; GARGANO, A.; HACISALIHOGLU, A.; IAZZI, F.; LA FAUCI, L.; LINARES, R.; LUBIAN, J.; MEDINA, N.; MORALLES, M.; OLIVEIRA, J.R.B.; PAKOU, A.; PANDOLA, L.; PETRASCU, H.; PINNA, F.; RUSSO, G.; SGOUROS, O.; SILVEIRA, M.A.G. da; SOLAKCI, S.O.; SOUKERAS, V.; SOULIOTIS, G.; TORRESI, D.; TUDISCO, S.; YILDIRIM, A.; ZAGATTO, V.A.B.
Background: Single-charge-exchange reactions are appropriate tools to study the nuclear response to one-particle/one-hole isospin probes, gaining additional interest from the connection to beta decay. This analogy has been recently extended to second order, connecting double-charge-exchange reactions and double beta decays. Nowadays, the availability of powerful experimental setups and advanced nuclear theories and models allows one to access precious information on key nuclear structure aspects embedded in the widely sought neutrinoless double beta decay. Purpose: We intend to bring to light the main nuclear structure and reaction features involved in the 18O+12C collision at 275 MeV incident energy. In this paper, the main focus is on the role of the initial- and final-state interactions in the overall reaction dynamics and on the single-particle nuclear structure properties accessed via the study of single-nucleon transfer reactions. Forthcoming articles will be devoted to go into the details of the response to one- and two-particle/hole isospin probes. Methods: Cross-section energy spectra and angular distributions were measured in a unique experimental setup for the 12C(18O, 18O)12C elastic and inelastic scattering, the 12C(18O, 17O)13C one-neutron stripping, the 12C(18O, 19F)11B one-proton pickup, and the 12C(18O, 18F)12B single-charge-exchange nuclear reactions. A unique comprehensive and coherent theoretical calculation, able to describe the whole network of direct reactions using state-of-the-art nuclear structure and reaction theories, was performed, and it is presented for the first time in this article. This holistic approach, applied both to the experimental and theoretical analysis, is the main feature and worth of the work here presented. Results: The energy and angular resolutions achieved in each reaction channel allowed us to isolate specific transitions and to map the diffraction patterns in the angular distributions. The cross-section calculations describe well the experimental data, both in terms of the absolute values and diffraction patterns. Although the distorted wave Born approximation (DWBA) calculations prove to be accurate in describing all the studied channels, better results are achieved when the couplings to inelastic transitions in both the incoming and outgoing partitions are introduced, as done in the coupled channels Born approximation (CCBA) calculations. Otherwise, no real improvement is found when the coupling effects among different partitions are explicitly taken into account in the coupled reaction channels (CRC) calculations. Conclusions: The multichannel approach proposed in this paper is a promising method for accurate investigations of direct reactions originating in heavy-ion collisions. This is quite appealing for the precise spectroscopy of heavy nuclei proposed in many areas of nuclear physics. An example is the NUMEN project with its challenging commitment to provide valuable information on neutrinoless double beta decay nuclear matrix elements from single- and double-charge-exchange cross-section measurements.
Measurement of fusion cross sections for sup(16)O+sup(16)(O)
2015 - DUARTE, J.G.; GASQUES, L.R.; OLIVEIRA, J.R.B.; ZAGATTO, V.A.B.; CHAMON, L.C.; MEDINA, N.H.; ADDED, N.; SEALE, W.A.; ALCANTARA NUNEZ, J.A.; ROSSI JUNIOR, E.S.; AMADOR VALENZUELA, P.; LEPINE SZILY, A.; FREITAS, A.S.; SCARDUELLI, V.; AGUIAR, V.A.P.; SHORTO, J.M.B.
Neutron activation analysis lifetimes
2010 - OKIMURA, H.H.; SILVEIRA, M.A.G. da; MEDINA, N.H.; ZAMBONI, C.B.
The measurement of cross sections of inelastic and transfer reactions with gamma-particle coincidence
2009 - OLIVEIRA, J.R.B.; ZAGATTO, V.; PEREIRA, D.; ALLEGRO, P.R.P.; CHAMON, L.C.; CYBULSKA, E.W.; LINARES, R.; MEDINA, N.H.; RIBAS, R.V.; ROSSI JUNIOR, E.S.; SEALE, W.A.; SILVA, C.P.; TOUFEN, D.L.; SILVEIRA, M.A.G.; ZAHN, G.S.; GENEZINI, F.A.; GASQUES, L.
In-beam gamma-ray spectroscopy of sup(66)Ga: Preliminary results
2009 - ALLEGRO, P.R.P.; MEDINA, N.H.; OLIVEIRA, J.R.B.; LINARES, R.; RIBAS, R.V.; CYBULSKA, E.W.; SEALE, W.A.; TOUFEN, D.L.; SILVEIRA, M.A.G.; ZAHN, G.S.; GENEZINI, F.A.
Identificacao elemental utilizando ativacao por neutrons
2008 - OKIMURA, HEITOR H.; SILVEIRA, MARCILEI A.G. da; MEDINA, NILBERTO H.; ZAMBONI, CIBELE
Vidas-medias por ativacao de neutrons
2008 - MATTOS, ANA P.; SILVEIRA, MARCILEI A.G. da; MEDINA, NILBERTO H.; ZAMBONI, CIBELE
Soil characterization with neutron activation
2007 - ZAMBONI, C.B.; SILVEIRA, M.A.G.; MEDINA, N.H.