1,100 results on '"Ur C. A."'
Search Results
2. Determination of level widths in 15N using nuclear resonance fluorescence
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Szücs T., Bemmerer D., Caciolli A., Fülöp Zs., Massarczyk R., Michelagnoli C., Reinhardt T. P., Schwengner R., Takács M. P., Ur C. A., Wagner A., and Wagner L.
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Physics ,QC1-999 - Abstract
Level widths in 15N have been measured with the nuclear resonance fluorescence (NRF) technique. Solid nitrogen compounds, bremsstrahlung, and HPGe detectors have been used as target, beam, and detectors, respectively. The preliminarily level widths are in agreement with the literature values, but more precise.
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- 2015
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3. The (n,γ) campaigns at EXILL
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Jolie J., Régis J.-M., Wilmsen D., Ahmed S., Pfeiffer M., Saed-Samii N., Warr N., Blanc A., Jentschel M., Köster U., Mutti P., Soldner T., Simpson G., De France G., Urban W., Drouet F., Vancraeyenest A., Baczyk P., Czerwinski M., Korgul A., Mazzocchi C., Rzaca-Urban T., Bruce A., Roberts O.J., Fraile L.M., Mach H., Paziy V., Ignatov A., Ilieva S., Kröll Th., Scheck M., Thürauf M., Ivanova D., Kisyov S., Lalkovski S., Podolyák Zs., Regan P.H., Korten W., Zielinska M., Salsac M.D., Habs D., Thirolf P.G., Ur C. A., Bernards C., Casten R.F., Cooper N., Werner V., Cakirli R.B., Leoni S., Benzoni G., Bocchi G., Bottoni S., Crespi F.C.L., Fornal B., Cieplicka N., Szpak B., Petrache C.M., Leguillon R., John R., Lorenz C., Massarczyk R., Schwengner R., Curien D., Lozeva R., Sengele L., Marginean N., and Lica R.
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Physics ,QC1-999 - Abstract
At the PF1B cold neutron beam line at the Institut Laue Langevin, the EXILL array consisting of EXOGAM, GASP and ILL-Clover detectors was used to perform (n,γ) measurements at very high coincidence rates. About ten different reactions were measured in autumn 2012 using a highly collimated cold neutron beam. In spring 2013, the EXOGAM array was combined with 16 LaBr3(Ce) scintillators in the EXILL&FATIMA campaign for the measurement of lifetimes using the generalised centroid difference method. We report on the properties of the set-ups and present first results from both campaigns.
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- 2015
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4. From EXILL (EXogam at the ILL) to FIPPS (FIssion Product Prompt γ-ray Spectrometer)
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Blanc A., Chebboubi A., de France G., Drouet F., Faust H., Jentschel M., Kessedjian G., Köster U., Leoni S., Materna T., Mutti P., Panebianco S., Sage C., Simpson G., Soldner T., Ur C. A., Urban W., and Vancraeyenest A.
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Physics ,QC1-999 - Abstract
Within the EXILL campaign a large and efficient cluster of Ge-detectors was installed around a very well collimated neutron beam. This has allowed to carry out rather complete spectroscopic studies close to the line of stability using the (n,γ) reaction. Neutron rich isotopes were produced by neutron induced fission and prompt spectroscopy was carried out. The isotope selection in this setup was based on a partially known level scheme and the use of triple coincidences. The latter is limiting the statistical sensitivity in the case of weak production yields. Based on the experiences of these campaigns we are currently developing a new setup: FIPPS (FIssion Product Prompt Spectroscopy). This setup combines a collimated neutron beam, a highly efficient cluster of Ge detectors, a gas filled magnet and auxiliary detectors. The presence of the gas filled magnet will allow us to identify fission products directly and should give access to a new quality of studies if compared to the EXILL campaign. The EXILL campaign and the FIPPS project are presented.
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- 2015
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5. Measurement of relative isotopic yield distribution of even-even fission fragments from $^{235}$U($n_{th}$,$f$) following $\gamma$ ray spectroscopy
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Dey, Aniruddha, Biswas, D. C., Chakraborty, A., Mukhopadhyay, S., Mondal, A. K., Danu, L. S., Mukherjee, B., Garg, S., Maheshwari, B., Jain, A. K., Blanc, A., de France, G., Jentschel, M., Köster, U., Leoni, S., Mutti, P., Simpson, G., Soldner, T., Ur, C. A., and Urban, W.
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Nuclear Experiment ,Nuclear Theory - Abstract
A detailed investigation on the relative isotopic distributions has been carried out for the first time in case of even-even correlated fission fragments for the $^{235}$U($n_{th}$,$f$) fission reaction. High-statistics data were obtained in a prompt $\gamma$ ray spectroscopy measurement during the EXILL campaign at ILL, Grenoble, France. The extensive off-line analysis of the coincidence data have been carried out using four different coincidence methods. Combining the results from 2-dimensional $\gamma-\gamma$ and 3-dimensional $\gamma-\gamma-\gamma$ coincidence analysis, a comprehensive picture of the relative isotopic yield distributions of the even-even neutron-rich fission fragments has emerged. The experimentally observed results have been substantiated by the theoretical calculations based on a novel approach of isospin conservation, and a reasonable agreement has been obtained. The calculations following the semi-empirical GEF model have also been carried out. The results from the GEF model calculations are found to be in fair agreement with the experimental results., Comment: Accepted in PRC; nucl-ex; nucl-th
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- 2021
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6. Medium-spin states of the neutron-rich nucleus $^{87}$Br
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Nyakó, B. M., Timár, J., Csatlós, M., Dombrádi, Zs., Krasznahorkay, A., Kuti, I., Sohler, D., Tornyi, T. G., Czerwiński, M., Rzcaca-Urban, T., Urban, W., Bcaczyk, P., Atanasova, L., Balabanski, D. L., Sieja, K., Blanc, A., Jentschel, M., Köster, U., Mutti, P., Soldner, T., de France, G., Simpson, G. S., and Ur, C. A.
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Nuclear Experiment - Abstract
Medium-spin excited states of the neutron-rich nucleus $^{87}$Br were observed and studied for the first time. They were populated in fission of $^{235}$U induced by the cold-neutron beam of the PF1B facility of the Institut Laue-Langevin, Grenoble. The measurement of $\gamma$ radiation following fission has been performed using the EXILL array of Ge detectors. The observed level scheme was compared with results of large valence space shell model calculations. The medium-spin level scheme consists of three band-like structures, which can be understood as bands built on the ${\pi}f_{5/2}$, ${\pi}(p_{3/2}+f_{5/2})$ and ${\pi}g_{9/2}$ configurations. The behavior of the observed ${\pi}g_{9/2}$ band at high spins shows a considerable deviation from the shell model predictions. This deviation in this band is probably the result of an increased collectivity, which can be understood assuming that the ${\pi}g_{9/2}$ high-$\it j$ proton polarizes the core.
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- 2021
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7. Low-lying bands with different quadrupole deformation in 155Dy
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Petkov P., Yavahchova M.S., Möller O., Dewald A., Saha B., Fitzler A., Jessen K., Tonev D., Klug T., Heinze S., Jolie J., von Brentano P., Goutev N., Bazzacco D., Ur C. A., Farnea C. A., Axiotis M., Lunardi S., de Angelis G., Napoli D. R., Marginean N., Martinez T., and Caprio M. A.
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Physics ,QC1-999 - Abstract
To investigate the interplay between collective and single particle degrees of freedom in odd nuclei, Recoil distance Doppler-shift and Doppler-shift attenuation lifetime measurements were carried out for levels in 155Dy in coincidence detection of gamma-rays. 26 lifetimes were determined using the Differential decay curve method. Particle plus triaxial rotor model (PTRM) calculations were performed to compare the experimental level scheme and transition strengths with theoretical ones in order to get information on the quadrupole deformation (є,γ) of the bands. As a result, different quadrupole deformations for the one-quasineutron bands at low and medium spins are deduced.
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- 2014
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8. AGATA modules as Compton polarimeters for the measurement of gamma-ray linear polarisation
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Melon B., Bizzeti P. G., Sona P., Michelagnoli C., Bazzacco D., Farnea E., Bizzeti–Sona A. M., de Angelis G., Gadea A., Gottardo A., Lunardi S., Lenzi S. M., Menegazzo R., Mengoni D., Nannini A., Napoli D. R., Perego A., Recchia F., Sahin E., Valiente–Dobon J. J., and Ur C. A.
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Physics ,QC1-999 - Abstract
The ability of a cluster of three segmented Ge crystals (“AGATA module”) acting as a Compton polarimeter to measure the linear polarization of gamma rays has been investigated at an energy close to 511 keV. Partially polarized gamma rays have been produced by Coulomb excitation of the first excited state of 104Pd a and 108Pd.
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- 2014
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9. Towards experiments at the new ELI-NP facility
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Balabanski D. L., Cata-Danil G., Filipescu D., Gales S., Negoita F., Tesileanu O., Ur C. A., Ursu I., and Zamfir N. V.
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Physics ,QC1-999 - Abstract
The Extreme Light Infrastructure (ELI) Pan-European initiative represents a major step forward in quest for extreme electromagnetic fields. The Extreme Light Infrastructure – Nuclear Physics (ELI-NP) laboratory is one of the three pillars of the ELI project, that aims to use such extreme electromagnetic fields for nuclear physics and quantum electrodynamics research. At ELI-NP two ten petawatt high-power laser systems together with a very brilliant narrow-width γ beam are the main research tools. Here the current status of the project and the experimental program related to nuclear research, which is under preparation at ELI-NP, are presented.
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- 2014
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10. International Workshop on Next Generation Gamma-Ray Source
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Howell, C. R., Ahmed, M. W., Afanasev, A., Alesini, D., Annand, J. R. M., Aprahamian, A., Balabanski, D. L., Benson, S. V., Bernstein, A., Brune, C. R., Byrd, J., Carlsten, B. E., Champagne, A. E., Chattopadhyay, S., Davis, D., Downie, E. J., Durham, M. J., Feldman, G., Gao, H., Geddes, C. G. R., Griesshammer, H. W., Hajima, R., Hao, H., Hornidge, D., Isaak, J., Janssens, R. V. F., Kendellen, D. P., Kovash, M. A., Martel, P. P., Meissner, Ulf-G., Miskimen, R., Pasquini, B., Phillips, D. R., Pietralla, N., Savran, D., Schindler, M. R., Sikora, M. H., Snow, W. M., Springer, R. P., Sun, C., Tang, C., Tiburzi, B., Tonchev, A. P., Tornow, W., Ur, C. A., Wang, D., Weller, H. R., Werner, V., Wu, Y. K., Yan, J., Zhao, Z., Zilges, A., and Zomer, F.
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Nuclear Experiment ,Nuclear Theory ,Physics - Accelerator Physics - Abstract
A workshop on The Next Generation Gamma-Ray Sources sponsored by the Office of Nuclear Physics at the Department of Energy, was held November 17--19, 2016 in Bethesda, Maryland. The goals of the workshop were to identify basic and applied research opportunities at the frontiers of nuclear physics that would be made possible by the beam capabilities of an advanced laser Compton beam facility. To anchor the scientific vision to realistically achievable beam specifications using proven technologies, the workshop brought together experts in the fields of electron accelerators, lasers, and optics to examine the technical options for achieving the beam specifications required by the most compelling parts of the proposed research programs. An international assembly of participants included current and prospective $\gamma$-ray beam users, accelerator and light-source physicists, and federal agency program managers. Sessions were organized to foster interactions between the beam users and facility developers, allowing for information sharing and mutual feedback between the two groups. The workshop findings and recommendations are summarized in this whitepaper.
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- 2020
11. Low-spin particle/hole-core excitations in $^{41,47,49}$Ca isotopes studied by cold-neutron capture reactions
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Bottoni, S., Cieplicka-Oryńczak, N., Leoni, S., Fornal, B., Colò, G., Bortignon, P. F., Bocchi, G., Bazzacco, D., Benzoni, G., Blanc, A., Bracco, A., Ceruti, S., Crespi, F. C. L., de France, G., Gamba, E. R., Iskra, Ł. W., Jentschel, M., Köster, U., Michelagnoli, C., Million, B., Mengoni, D., Mutti, P., Niu, Y., Porzio, C., Simpson, G., Soldner, T., Szpak, B., Türler, A., Ur, C. A., and Urban, W.
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Nuclear Experiment - Abstract
We present recent results on the structure of the one-valence-particle $^{41}$Ca and $^{49}$Ca, and one-valence-hole $^{47}$Ca, nuclei. The isotopes of interest were populated via the cold-neutron capture reactions $^{40}$Ca(n,$\gamma$), $^{48}$Ca(n,$\gamma$) and $^{46}$Ca(n,$\gamma$), respectively. The experiments were performed at the Institut Laue-Langevin, within the EXILL campaign, which employed a large array of HPGe detectors. The $\gamma$ decay and level schemes of these nuclei were investigated by $\gamma$-ray coincidence relationships, leading to the identification of 41, 10, and 6 new transitions in $^{41}$Ca, $^{47}$Ca, and $^{49}$Ca, respectively. Branching ratios and intensities were extracted for the $\gamma$ decay from each state, and $\gamma$-ray angular correlations were performed to establish a number of transition multipolarities and mixing ratios, thus helping in the spin assignment of the states. The experimental findings are discussed along with microscopic, self-consistent beyond-mean-field calculations performed with the Hybrid Configuration Mixing model, based on a Skyrme SkX Hamiltonian. The latter suggests that a fraction of the low-spin states of the $^{41}$Ca, $^{49}$Ca, and $^{47}$Ca nuclei is characterized by the coexistence of either 2p-1h and 1p-2h excitations, or couplings between single-particle/hole degrees of freedom and collective vibrations (phonons) of the doubly-magic "core".
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- 2020
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12. Manifestation of the Berry phase in the atomic nucleus $^{213}$Pb
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Valiente-Dobón, J. J., Gottardo, A., Benzoni, G., Gadea, A., Lunardi, S., Algora, A., de Angelis, G., Bazzacco, D., Benlliure, J., Boutachkov, P., Bracco, A., Bruce, A. M., Camera, F., Casarejos, E., Cortés, M. L., Crespi, F. C. L., Corsi, A., Domingo-Pardo, C., Doncel, M., Engert, T., Geissel, H., Gerl, J., Goel, N., Górska, M., Grebosz, J., Gregor, E., Habermann, T., Klupp, S., Kojouharov, I., Kurz, N., Lenzi, S. M., Leoni, S., Mandal, S., Menegazzo, R., Mengoni, D., Million, B., Morales, A. I., Napoli, D. R., Naqvi, F., Nociforo, C., Pfutzner, M., Pietri, S., Podolyak, Zs., Prochazka, A., Recchia, F., Regan, P. H., Rudolph, D., Sahin, E., Scha_ner, H., Sharma, A., Sitar, B., Siwal, D., Strmen, P., Szarka, I., Ur, C. A., Walker, P. M., Weick, H., Wieland, O., Wollersheim, H-J., and Van Isacker, P.
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Nuclear Experiment ,Nuclear Theory - Abstract
The neutron-rich $^{213}$Pb isotope was produced in the fragmentation of a primary 1 GeV $A$ $^{238}$U beam, separated in FRS in mass and atomic number, and then implanted for isomer decay $\gamma$-ray spectroscopy with the RISING setup at GSI. A newly observed isomer and its measured decay properties indicate that states in $^{213}$Pb are characterized by the seniority quantum number that counts the nucleons not in pairs coupled to angular momentum $J=0$. The conservation of seniority is a consequence of the Berry phase associated with particle-hole conjugation, which becomes gauge invariant and therefore observable in semi-magic nuclei where nucleons half-fill the valence shell. The $\gamma$-ray spectroscopic observables in $^{213}$Pb are thus found to be driven by two mechanisms, particle-hole conjugation and seniority conservation, which are intertwined through the Berry phase.
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- 2020
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13. Normal and intruder configurations in $^{34}$Si populated in the $\beta^-$ decay of $^{34}$Mg and $^{34}$Al
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Lica, R., Rotaru, F., Borge, M. J. G., Grevy, S., Negoita, F., Poves, A., Sorlin, O., Andreyev, A. N., Borcea, R., Costache, C., De Witte, H., Fraile, L. M., Greenlees, P. T., Huyse, M., Ionescu, A., Kisyov, S., Konki, J., Lazarus, I., Madurga, M., Marginean, N., Marginean, R., Mihai, C., Mihai, R. E., Negret, A., Nowacki, F., Page, R. D., Pakarinen, J., Pucknell, V., Rahkila, P., Rapisarda, E., Serban, A., Sotty, C. O., Stan, L., Stanoiu, M., Tengblad, O., Turturica, A., Van Duppen, P., Warr, N., Dessagne, Ph., Stora, T., Borcea, C., Calinescu, S., Daugas, J. M., Filipescu, D., Kuti, I., Franchoo, S., Gheorghe, I., Morfouace, P., Morel, P., Mrazek, J., Pietreanu, D., Sohler, D., Stefan, I., Suvaila, R., Toma, S., and Ur, C. A.
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Nuclear Experiment - Abstract
The structure of $^{34}$Si was studied through $\gamma$ spectroscopy separately in the $\beta^-$ decays of $^{34}$Mg and $^{34}$Al at the ISOLDE facility of CERN. Different configurations in $^{34}$Si were populated independently from the two recently identified $\beta$-decaying states in $^{34}$Al having spin-parity assignments $J^\pi = 4^-$ dominated by the normal configuration $\pi (d_{5/2})^{-1} \otimes \nu (f_{7/2})$ and $J^\pi = 1^+$ by the intruder configuration $\pi (d_{5/2})^{-1} \otimes \nu (d_{3/2})^{-1}(f_{7/2})^{2}$. The paper reports on spectroscopic properties of $^{34}$Si such as an extended level scheme, spin and parity assignments based on log($ft$) values and $\gamma$-ray branching ratios, absolute $\beta$ feeding intensities and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of $^{34}$Si. Large scale shell-model calculations using the {\sc sdpf-u-mix} interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of {\sc sdpf-u-mix}, the $N=20$ shell gap, the level of mixing between normal and intruder configurations for the 0$_1^+$, 0$_2^+$ and 2$_1^+$ states and the absence of triaxial deformation in $^{34}$Si.
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- 2019
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14. Characterization of 30 $^{76}$Ge enriched Broad Energy Ge detectors for GERDA Phase II
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GERDA collaboration, Agostini, M., Bakalyarov, A. M., Andreotti, E., Balata, M., Barabanov, I., Baudis, L., Barros, N., Bauer, C., Bellotti, E., Belogurov, S., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Borowicz, D., Brudanin, V., Brugnera, R., Budjáš, D., Caldwell, A., Cattadori, C., Chernogorov, A., D'Andrea, V., Demidova, E. V., Di Marco, N., Domula, A., Doroshkevich, E., Egorov, V., Falkenstein, R., Freund, K., Gangapshev, A., Garfagnini, A., Gooch, C., Grabmayr, P., Gurentsov, V., Gusev, K., Hakenmüller, J., Hegai, A., Heisel, M., Hemmer, S., Hiller, R., Hofmann, W., Hult, M., Inzhechik, L. V., Csáthy, J. Janicskó, Jochum, J., Junker, M., Kazalov, V., Kermaidic, Y., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Kish, A., Klimenko, A., Kneißl, R., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lehnert, B., Liao, Y., Lindner, M., Lippi, I., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Majorovits, B., Maneschg, W., Miloradovic, M., Mingazheva, R., Misiaszek, M., Moseev, P., Nemchenok, I., Panas, K., Pandola, L., Pelczar, K., Pullia, A., Ransom, C., Riboldi, S., Rumyantseva, N., Sada, C., Salamida, F., Salathe, M., Schmitt, C., Schneider, B., Schönert, S., Schütz, A-K., Schulz, O., Schwingenheuer, B., Selivanenko, O., Shevchik, E., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Ur, C. A., Vanhoefer, L., Vasenko, A. A., Veresnikova, A., von Sturm, K., Wagner, V., Wegmann, A., Wester, T., Wiesinger, C., Wojcik, M., Yanovich, E., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zsigmond, A. J., Zuber, K., and Zuzel, G.
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Physics - Instrumentation and Detectors - Abstract
The GERmanium Detector Array (GERDA) is a low background experiment located at the Laboratori Nazionali del Gran Sasso in Italy, which searches for neutrinoless double beta decay of $^{76}$Ge into $^{76}$Se+2e$^-$. GERDA has been conceived in two phases. Phase II, which started in December 2015, features several novelties including 30 new Ge detectors. These were manufactured according to the Broad Energy Germanium (BEGe) detector design that has a better background discrimination capability and energy resolution compared to formerly widely-used types. Prior to their installation, the new BEGe detectors were mounted in vacuum cryostats and characterized in detail in the HADES underground laboratory in Belgium. This paper describes the properties and the overall performance of these detectors during operation in vacuum. The characterization campaign provided not only direct input for GERDA Phase II data collection and analyses, but also allowed to study detector phenomena, detector correlations as well as to test the strength of pulse shape simulation codes., Comment: 29 pages, 18 figures
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- 2019
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15. Design concept of a γ -ray beam with low bandwidth and high spectral density
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Constantin, P., primary, Matei, C., additional, and Ur, C. A., additional
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- 2024
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16. The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus 133Sb
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Bocchi, G., Leoni, S., Fornal, B., Colo', G., Bortignon, P. F., Bottoni, S., Bracco, A., Michelagnoli, C., Bazzacco, D., Blanc, A., De France, G., Jentschel, M., Koster, U., Mutti, P., Regis, J. -M., Simpson, G., Soldner, T., Ur, C. A., Urban, W., Fraile, L. M., Lozeva, R., Belvito, B., Benzoni, G., Bruce, A., Carroll, R., Cieplicka-Orynczak, N., Crespi, F. C. L., Didierjean, F., Jolie, J., Korten, W., Kroll, T., Lalkovski, S., Mach, H., Marginean, N., Melon, B., Mengoni, D., Million, B., Nannini, A., Napoli, D., Olaizola, B., Paziy, V., Podolyakn, Zs., Regann, P. H., Saed-Samii, N., Szpak, B., and Vedia, V.
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Nuclear Experiment ,Nuclear Theory - Abstract
The gamma-ray decay of excited states of the one-valence-proton nucleus 133Sb has been studied using cold-neutron induced fission of 235U and 241Pu targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between gamma-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 micros isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr3(Ce) scintillators, reveals a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus 132Sn and the valence proton, using the Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin.
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- 2016
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17. High-spin structures in Xe 132 and Xe 133 and evidence for isomers along the N=79 isotones
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Vogt, A, Siciliano, M, Birkenbach, B, Reiter, P, Hadyńska-Klȩk, K, Wheldon, C, Valiente-Dobón, JJ, Teruya, E, Yoshinaga, N, Arnswald, K, Bazzacco, D, Blazhev, A, Bracco, A, Bruyneel, B, Chakrawarthy, RS, Chapman, R, Cline, D, Corradi, L, Crespi, FCL, Cromaz, M, De Angelis, G, Eberth, J, Fallon, P, Farnea, E, Fioretto, E, Fransen, C, Freeman, SJ, Fu, B, Gadea, A, Gelletly, W, Giaz, A, Görgen, A, Gottardo, A, Hayes, AB, Hess, H, Hetzenegger, R, Hirsch, R, Hua, H, John, PR, Jolie, J, Jungclaus, A, Karayonchev, V, Kaya, L, Korten, W, Lee, IY, Leoni, S, Liang, X, Lunardi, S, MacChiavelli, AO, Menegazzo, R, Mengoni, D, Michelagnoli, C, Mijatović, T, Montagnoli, G, Montanari, D, Müller-Gatermann, C, Napoli, D, Pearson, CJ, Podolyák, Z, Pollarolo, G, Pullia, A, Queiser, M, Recchia, F, Regan, PH, Régis, JM, Saed-Samii, N, Şahin, E, Scarlassara, F, Seidlitz, M, Siebeck, B, Sletten, G, Smith, JF, Söderström, PA, Stefanini, AM, Stezowski, O, Szilner, S, Szpak, B, Teng, R, Ur, C, Warner, DD, Wolf, K, Wu, CY, and Zell, KO
- Abstract
The transitional nuclei Xe132 and Xe133 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+Pb208 MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the Xe136+Pt198 MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a Te130(α,xn)Xe134-xn fusion-evaporation reaction employing the HORUS γ-ray array at the University of Cologne. The high-spin level schemes are considerably extended above the Jπ=(7-) and (10+) isomers in Xe132 and above the 11/2- isomer in Xe133. The results are compared to the high-spin systematics of the Z=54 as well as the N=78 and N=79 chains. Furthermore, evidence is found for a long-lived (T1/2â‰1μs) isomer in Xe133 which closes a gap along the N=79 isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.
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- 2017
18. High-spin structures in Xe132 and Xe133 and evidence for isomers along the N=79 isotones
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Vogt, A, Siciliano, M, Birkenbach, B, Reiter, P, Hadyńska-Klęk, K, Wheldon, C, Valiente-Dobón, JJ, Teruya, E, Yoshinaga, N, Arnswald, K, Bazzacco, D, Blazhev, A, Bracco, A, Bruyneel, B, Chakrawarthy, RS, Chapman, R, Cline, D, Corradi, L, Crespi, FCL, Cromaz, M, de Angelis, G, Eberth, J, Fallon, P, Farnea, E, Fioretto, E, Fransen, C, Freeman, SJ, Fu, B, Gadea, A, Gelletly, W, Giaz, A, Görgen, A, Gottardo, A, Hayes, AB, Hess, H, Hetzenegger, R, Hirsch, R, Hua, H, John, PR, Jolie, J, Jungclaus, A, Karayonchev, V, Kaya, L, Korten, W, Lee, IY, Leoni, S, Liang, X, Lunardi, S, Macchiavelli, AO, Menegazzo, R, Mengoni, D, Michelagnoli, C, Mijatović, T, Montagnoli, G, Montanari, D, Müller-Gatermann, C, Napoli, D, Pearson, CJ, Podolyák, Zs, Pollarolo, G, Pullia, A, Queiser, M, Recchia, F, Regan, PH, Régis, J-M, Saed-Samii, N, Şahin, E, Scarlassara, F, Seidlitz, M, Siebeck, B, Sletten, G, Smith, JF, Söderström, P-A, Stefanini, AM, Stezowski, O, Szilner, S, Szpak, B, Teng, R, Ur, C, Warner, DD, Wolf, K, Wu, CY, and Zell, KO
- Subjects
Nuclear and Plasma Physics ,Synchrotrons and Accelerators ,Physical Sciences ,Nuclear and plasma physics - Abstract
The transitional nuclei Xe132 and Xe133 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+Pb208 MNT reactions employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (ii) in the Xe136+Pt198 MNT reaction employing the GAMMASPHERE spectrometer in combination with the gas-detector array CHICO, and (iii) as an evaporation residue after a Te130(α,xn)Xe134-xn fusion-evaporation reaction employing the HORUS γ-ray array at the University of Cologne. The high-spin level schemes are considerably extended above the Jπ=(7-) and (10+) isomers in Xe132 and above the 11/2- isomer in Xe133. The results are compared to the high-spin systematics of the Z=54 as well as the N=78 and N=79 chains. Furthermore, evidence is found for a long-lived (T1/2â‰1μs) isomer in Xe133 which closes a gap along the N=79 isotones. Shell-model calculations employing the SN100PN and PQM130 effective interactions reproduce the experimental findings and provide guidance to the interpretation of the observed high-spin features.
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- 2017
19. Isomers and high-spin structures in the N=81 isotones Xe 135 and Ba 137
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Vogt, A, Birkenbach, B, Reiter, P, Blazhev, A, Siciliano, M, Hadyńska-Klȩk, K, Valiente-Dobón, JJ, Wheldon, C, Teruya, E, Yoshinaga, N, Arnswald, K, Bazzacco, D, Bowry, M, Bracco, A, Bruyneel, B, Chakrawarthy, RS, Chapman, R, Cline, D, Corradi, L, Crespi, FCL, Cromaz, M, De Angelis, G, Eberth, J, Fallon, P, Farnea, E, Fioretto, E, Freeman, SJ, Fu, B, Gadea, A, Geibel, K, Gelletly, W, Gengelbach, A, Giaz, A, Görgen, A, Gottardo, A, Hayes, AB, Hess, H, Hirsch, R, Hua, H, John, PR, Jolie, J, Jungclaus, A, Kaya, L, Korten, W, Lee, IY, Leoni, S, Lewandowski, L, Liang, X, Lunardi, S, Macchiavelli, AO, Menegazzo, R, Mengoni, D, Michelagnoli, C, Mijatović, T, Montagnoli, G, Montanari, D, Müller-Gatermann, C, Napoli, D, Pearson, CJ, Pellegri, L, Podolyák, Z, Pollarolo, G, Pullia, A, Queiser, M, Radeck, F, Recchia, F, Regan, PH, Rosiak, D, Saed-Samii, N, Şahin, E, Scarlassara, F, Schneiders, D, Seidlitz, M, Siebeck, B, Sletten, G, Smith, JF, Söderström, PA, Stefanini, AM, Steinbach, T, Stezowski, O, Szilner, S, Szpak, B, Teng, R, Ur, C, Vandone, V, Warner, DD, Wiens, A, Wu, CY, and Zell, KO
- Abstract
The high-spin structures and isomers of the N=81 isotones Xe135 and Ba137 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+U238 and (ii) Xe136+Pb208 MNT reactions employing the high-resolution Advanced Gamma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (iii) in the Xe136+Pt198 MNT reaction employing the γ-ray array GAMMASPHERE in combination with the gas-detector array CHICO, and (iv) via a B11+Te130 fusion-evaporation reaction with the HORUS γ-ray array at the University of Cologne. The high-spin level schemesof Xe135 and Ba137 are considerably extended to higher energies. The 2058-keV (19/2-) state in Xe135 is identified as an isomer, closing a gap in the systematics along the N=81 isotones. Its half-life is measured to be 9.0(9) ns, corresponding to a reduced transition probability of B(E2,19/2-→15/2-)=0.52(6) W.u. The experimentally deduced reduced transition probabilities of the isomeric states are compared to shell-model predictions. Latest shell-model calculations reproduce the experimental findings generally well and provide guidance to the interpretation of the new levels.
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- 2017
20. Isomers and high-spin structures in the N=81 isotones Xe135 and Ba137
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Vogt, A, Birkenbach, B, Reiter, P, Blazhev, A, Siciliano, M, Hadyńska-Klęk, K, Valiente-Dobón, JJ, Wheldon, C, Teruya, E, Yoshinaga, N, Arnswald, K, Bazzacco, D, Bowry, M, Bracco, A, Bruyneel, B, Chakrawarthy, RS, Chapman, R, Cline, D, Corradi, L, Crespi, FCL, Cromaz, M, de Angelis, G, Eberth, J, Fallon, P, Farnea, E, Fioretto, E, Freeman, SJ, Fu, B, Gadea, A, Geibel, K, Gelletly, W, Gengelbach, A, Giaz, A, Görgen, A, Gottardo, A, Hayes, AB, Hess, H, Hirsch, R, Hua, H, John, PR, Jolie, J, Jungclaus, A, Kaya, L, Korten, W, Lee, IY, Leoni, S, Lewandowski, L, Liang, X, Lunardi, S, Macchiavelli, AO, Menegazzo, R, Mengoni, D, Michelagnoli, C, Mijatović, T, Montagnoli, G, Montanari, D, Müller-Gatermann, C, Napoli, D, Pearson, CJ, Pellegri, L, Podolyák, Zs, Pollarolo, G, Pullia, A, Queiser, M, Radeck, F, Recchia, F, Regan, PH, Rosiak, D, Saed-Samii, N, Şahin, E, Scarlassara, F, Schneiders, D, Seidlitz, M, Siebeck, B, Sletten, G, Smith, JF, Söderström, P-A, Stefanini, AM, Steinbach, T, Stezowski, O, Szilner, S, Szpak, B, Teng, R, Ur, C, Vandone, V, Warner, DD, Wiens, A, Wu, CY, and Zell, KO
- Subjects
Nuclear and Plasma Physics ,Synchrotrons and Accelerators ,Physical Sciences ,Nuclear and plasma physics - Abstract
The high-spin structures and isomers of the N=81 isotones Xe135 and Ba137 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Both nuclei are populated (i) in Xe136+U238 and (ii) Xe136+Pb208 MNT reactions employing the high-resolution Advanced Gamma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA, (iii) in the Xe136+Pt198 MNT reaction employing the γ-ray array GAMMASPHERE in combination with the gas-detector array CHICO, and (iv) via a B11+Te130 fusion-evaporation reaction with the HORUS γ-ray array at the University of Cologne. The high-spin level schemesof Xe135 and Ba137 are considerably extended to higher energies. The 2058-keV (19/2-) state in Xe135 is identified as an isomer, closing a gap in the systematics along the N=81 isotones. Its half-life is measured to be 9.0(9) ns, corresponding to a reduced transition probability of B(E2,19/2-→15/2-)=0.52(6) W.u. The experimentally deduced reduced transition probabilities of the isomeric states are compared to shell-model predictions. Latest shell-model calculations reproduce the experimental findings generally well and provide guidance to the interpretation of the new levels.
- Published
- 2017
21. Determination of gamma-ray widths in $^{15}$N using nuclear resonance fluorescence
- Author
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Szücs, T., Bemmerer, D., Caciolli, A., Fülöp, Zs., Massarczyk, R., Michelagnoli, C., Reinhardt, T. P., Schwengner, R., Takács, M. P., Ur, C. A., Wagner, A., and Wagner, L.
- Subjects
Nuclear Experiment - Abstract
The stable nucleus $^{15}$N is the mirror of $^{15}$O, the bottleneck in the hydrogen burning CNO cycle. Most of the $^{15}$N level widths below the proton emission threshold are known from just one nuclear resonance fluorescence (NRF) measurement, with limited precision in some cases. A recent experiment with the AGATA demonstrator array determined level lifetimes using the Doppler Shift Attenuation Method (DSAM) in $^{15}$O. As a reference and for testing the method, level lifetimes in $^{15}$N have also been determined in the same experiment. The latest compilation of $^{15}$N level properties dates back to 1991. The limited precision in some cases in the compilation calls for a new measurement in order to enable a comparison to the AGATA demonstrator data. The widths of several $^{15}$N levels have been studied with the NRF method. The solid nitrogen compounds enriched in $^{15}$N have been irradiated with bremsstrahlung. The $\gamma$-rays following the deexcitation of the excited nuclear levels were detected with four HPGe detectors. Integrated photon-scattering cross sections of ten levels below the proton emission threshold have been measured. Partial gamma-ray widths of ground-state transitions were deduced and compared to the literature. The photon scattering cross sections of two levels above the proton emission threshold, but still below other particle emission energies have also been measured, and proton resonance strengths and proton widths were deduced. Gamma and proton widths consistent with the literature values were obtained, but with greatly improved precision., Comment: Final published version, minor grammar changes, 10 pages, 4 figures, 8 tables; An addendum is published where the last section is revised: T. Sz\"ucs and P. Mohr, Phys. Rev. C 92, 044328 (2015) [arXiv:1510.04956]
- Published
- 2015
- Full Text
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22. $2\nu\beta\beta$ decay of $^{76}$Ge into excited states with GERDA Phase I
- Author
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Agostini, M., Allardt, M., Bakalyarov, A. M., Balata, M., Barabanov, I., Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Borowicz, D., Brudanin, V., Brugnera, R., Budjáš, D., Caldwell, A., Cattadori, C., Chernogorov, A., D'Andrea, V., Demidova, E. V., di Vacri, A., Domula, A., Doroshkevich, E., Egorov, V., Falkenstein, R., Fedorova, O., Freund, K., Frodyma, N., Gangapshev, A., Garfagnini, A., Gooch, C., Grabmayr, P., Gurentsov, V., Gusev, K., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Csáthy, J. Janicskó, Jochum, J., Junker, M., Kazalov, V., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Majorovits, B., Maneschg, W., Medinaceli, E., Mi, Y., Misiaszek, M., Moseev, P., Nemchenok, I., Palioselitis, D., Panas, K., Pandola, L., Pelczar, K., Pullia, A., Riboldi, S., Rumyantseva, N., Sada, C., Salathe, M., Schmitt, C., Schneider, B., Schreiner, J., Schulz, O., Schwingenheuer, B., Schönert, S., Schütz, A-K., Selivanenko, O., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Stepaniuk, M., Ur, C. A., Vanhoefer, L., Vasenko, A. A., Veresnikova, A., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wester, T., Wilsenach, H., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
- Subjects
High Energy Physics - Experiment ,Nuclear Experiment - Abstract
Two neutrino double beta decay of $^{76}$Ge to excited states of $^{76}$Se has been studied using data from Phase I of the GERDA experiment. An array composed of up to 14 germanium detectors including detectors that have been isotopically enriched in $^{76}$Ge was deployed in liquid argon. The analysis of various possible transitions to excited final states is based on coincidence events between pairs of detectors where a de-excitation $\gamma$ ray is detected in one detector and the two electrons in the other. No signal has been observed and an event counting profile likelihood analysis has been used to determine Frequentist 90\,\% C.L. bounds for three transitions: ${0^+_{\rm g.s.}-2^+_1}$: $T^{2\nu}_{1/2}>$1.6$\cdot10^{23}$ yr, ${0^+_{\rm g.s.}-0^+_1}$: $T^{2\nu}_{1/2}>$3.7$\cdot10^{23}$ yr and ${0^+_{\rm g.s.}-2^+_2}$: $T^{2\nu}_{1/2}>$2.3$\cdot10^{23}$ yr. These bounds are more than two orders of magnitude larger than those reported previously. Bayesian 90\,\% credibility bounds were extracted and used to exclude several models for the ${0^+_{\rm g.s.}-0^+_1}$ transition.
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- 2015
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23. Improvement of the Energy Resolution via an Optimized Digital Signal Processing in GERDA Phase I
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Agostini, M., Allardt, M., Bakalyarov, A. M., Balata, M., Barabanov, I., Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Borowicz, D., Brudanin, V., Brugnera, R., Budjáš, D., Caldwell, A., Cattadori, C., Chernogorov, A., D'Andrea, V., Demidova, E. V., di Vacri, A., Domula, A., Doroshkevich, E., Egorov, V., Falkenstein, R., Fedorova, O., Freund, K., Frodyma, N., Gangapshev, A., Garfagnini, A., Grabmayr, P., Gurentsov, V., Gusev, K., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Csáthy, J. Janicskó, Jochum, J., Junker, M., Kazalov, V., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Majorovits, B., Maneschg, W., Medinaceli, E., Misiaszek, M., Moseev, P., Nemchenok, I., Palioselitis, D., Panas, K., Pandola, L., Pelczar, K., Pullia, A., Riboldi, S., Rumyantseva, N., Sada, C., Salathe, M., Schmitt, C., Schneider, B., Schönert, S., Schreiner, J., Schütz, A. -K., Schulz, O., Schwingenheuer, B., Selivanenko, O., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Stepaniuk, M., Ur, C. A., Vanhoefer, L., Vasenko, A. A., Veresnikova, A., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wester, T., Wilsenach, H., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
- Subjects
Physics - Instrumentation and Detectors ,Nuclear Experiment - Abstract
An optimized digital shaping filter has been developed for the GERDA experiment which searches for neutrinoless double beta decay in 76Ge. The GERDA Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) at the 76Ge Q value for 0\nu\beta\beta decay is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping fillter., Comment: 12 pages, 16 figures
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- 2015
24. Results on $\beta\beta$ decay with emission of two neutrinos or Majorons in $^{76}$Ge from GERDA Phase I
- Author
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Agostini, M., Allardt, M., Bakalyarov, A. M., Balata, M., Barabanov, I., Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Borowicz, D., Brudanin, V., Brugnera, R., Budjáš, D., Caldwell, A., Cattadori, C., Chernogorov, A., D'Andrea, V., Demidova, E. V., di Vacri, A., Domula, A., Doroshkevich, E., Egorov, V., Falkenstein, R., Fedorova, O., Freund, K., Frodyma, N., Gangapshev, A., Garfagnini, A., Grabmayr, P., Gurentsov, V., Gusev, K., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Csáthy, J. Janicskó, Jochum, J., Junker, M., Kazalov, V., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Majorovits, B., Maneschg, W., Medinaceli, E., Misiaszek, M., Moseev, P., Nemchenok, I., Palioselitis, D., Panas, K., Pandola, L., Pelczar, K., Pullia, A., Riboldi, S., Rumyantseva, N., Sada, C., Salathe, M., Schmitt, C., Schreiner, J., Schulz, O., Schwingenheuer, B., Schönert, S., Selivanenko, O., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Stepaniuk, M., Ur, C. A., Vanhoefer, L., Vasenko, A. A., Veresnikova, A., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wester, T., Wilsenach, H., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
- Subjects
Nuclear Experiment ,Physics - Instrumentation and Detectors - Abstract
A search for neutrinoless $\beta\beta$ decay processes accompanied with Majoron emission has been performed using data collected during Phase I of the GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso of INFN (Italy). Processes with spectral indices n = 1, 2, 3, 7 were searched for. No signals were found and lower limits of the order of 10$^{23}$ yr on their half-lives were derived, yielding substantially improved results compared to previous experiments with $^{76}$Ge. A new result for the half-life of the neutrino-accompanied $\beta\beta$ decay of $^{76}$Ge with significantly reduced uncertainties is also given, resulting in $T^{2\nu}_{1/2} = (1.926 \pm 0.095)\cdot10^{21}$ yr., Comment: 3 Figures
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- 2015
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25. Production, characterization and operation of $^{76}$Ge enriched BEGe detectors in GERDA
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Agostini, M., Allardt, M., Andreotti, E., Bakalyarov, A. M., Balata, M., Barabanov, I., Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Borowicz, D., Brudanin, V., Brugnera, R., Budjas, D., Caldwel, A., Cattadori, C., Chernogorov, A., D'Andrea, V., Demidova, E. V., Domula, A., Egorov, V., Falkenstein, R., Freund, K., Frodyma, N., Gangapshev, A., Garfagnini, A., Gotti, C., Grabmayr, P., Gurentsov, V., Gusev, K., Hampel, W., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Ioannucci, L., Csathy, J. Janicsko, Jochum, J., Junker, M., Kazalov, V., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Majorovits, B., Maneschg, W., Misiaszek, M., Nemchenok, I., Nisi, S., O'Shaughnessy, C., Palioselitis, D., Pandola, L., Pelczar, K., Pessina, G., Pullia, A., Riboldi, S., Rumyantseva, N., Sada, C., Salathe, M., Schmitt, C., Schreiner, J., Schulz, O., Schwingenheuer, B., Schönert, S., Shevchik, E., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Strecker, H., Ur, C. A., Vanhoefer, L., Vasenko, A. A., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wester, T., Wilsenach, H., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
- Subjects
Physics - Instrumentation and Detectors ,High Energy Physics - Experiment ,Nuclear Experiment - Abstract
The GERmanium Detector Array (GERDA) at the Gran Sasso Underground Laboratory (LNGS) searches for the neutrinoless double beta decay (0{\nu}{\beta}{\beta}) of $^{76}$Ge. Germanium detectors made of material with an enriched $^{76}$Ge fraction act simultaneously as sources and detectors for this decay. During Phase I of the experiment mainly refurbished semi-coaxial Ge detectors from former experiments were used. For the upcoming Phase II, 30 new $^{76}$Ge enriched detectors of broad energy germanium (BEGe)-type were produced. A subgroup of these detectors has already been deployed in GERDA during Phase I. The present paper reviews the complete production chain of these BEGe detectors including isotopic enrichment, purification, crystal growth and diode production. The efforts in optimizing the mass yield and in minimizing the exposure of the $^{76}$Ge enriched germanium to cosmic radiation during processing are described. Furthermore, characterization measurements in vacuum cryostats of the first subgroup of seven BEGe detectors and their long-term behavior in liquid argon are discussed. The detector performance fulfills the requirements needed for the physics goals of GERDA Phase~II., Comment: 23 pages, 21 figures
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- 2014
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26. High-spin structure of Xe 134
- Author
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Vogt, A, Birkenbach, B, Reiter, P, Blazhev, A, Siciliano, M, Valiente-Dobón, JJ, Wheldon, C, Bazzacco, D, Bowry, M, Bracco, A, Bruyneel, B, Chakrawarthy, RS, Chapman, R, Cline, D, Corradi, L, Crespi, FCL, Cromaz, M, De Angelis, G, Eberth, J, Fallon, P, Farnea, E, Fioretto, E, Freeman, SJ, Gadea, A, Geibel, K, Gelletly, W, Gengelbach, A, Giaz, A, Görgen, A, Gottardo, A, Hayes, AB, Hess, H, Hua, H, John, PR, Jolie, J, Jungclaus, A, Korten, W, Lee, IY, Leoni, S, Liang, X, Lunardi, S, Macchiavelli, AO, Menegazzo, R, Mengoni, D, Michelagnoli, C, Mijatović, T, Montagnoli, G, Montanari, D, Napoli, D, Pearson, CJ, Pellegri, L, Podolyák, Z, Pollarolo, G, Pullia, A, Radeck, F, Recchia, F, Regan, PH, Şahin, E, Scarlassara, F, Sletten, G, Smith, JF, Söderström, PA, Stefanini, AM, Steinbach, T, Stezowski, O, Szilner, S, Szpak, B, Teng, R, Ur, C, Vandone, V, Ward, D, Warner, DD, Wiens, A, and Wu, CY
- Abstract
Detailed spectroscopic information on the N∼82 nuclei is necessary to benchmark shell-model calculations in the region. The nuclear structure above long-lived isomers in Xe134 is investigated after multinucleon transfer (MNT) and actinide fission. Xenon-134 was populated as (i) a transfer product in Xe136+U238 and Xe136+Pb208 MNT reactions and (ii) as a fission product in the Xe136+U238 reaction employing the high-resolution Advanced Gamma Tracking Array (AGATA). Trajectory reconstruction has been applied for the complete identification of beamlike transfer products with the magnetic spectrometer PRISMA. The Xe136+Pt198 MNT reaction was studied with the γ-ray spectrometer GAMMASPHERE in combination with the gas detector array Compact Heavy Ion Counter (CHICO). Several high-spin states in Xe134 on top of the two long-lived isomers are discovered based on γγ-coincidence relationships and information on the γ-ray angular distributions as well as excitation energies from the total kinetic energy loss and fission fragments. The revised level scheme of Xe134 is extended up to an excitation energy of 5.832 MeV with tentative spin-parity assignments up to 16+. Previous assignments of states above the 7- isomer are revised. Latest shell-model calculations employing two different effective interactions reproduce the experimental findings and support the new spin and parity assignments.
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- 2016
27. Performance of the Fully Digital FPGA-based Front-End Electronics for the GALILEO Array
- Author
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Barrientos, D., Bellato, M., Bazzacco, D., Bortolato, D., Cocconi, P., Gadea, A., González, V., Gulmini, M., Isocrate, R., Mengoni, D., Pullia, A., Recchia, F., Rosso, D., Sanchis, E., Toniolo, N., Ur, C. A., and Valiente-Dobón, J. J.
- Subjects
Physics - Instrumentation and Detectors ,Nuclear Experiment - Abstract
In this work we present the architecture and results of a fully digital Front End Electronics (FEE) read out system developed for the GALILEO array. The FEE system, developed in collaboration with the Advanced Gamma Tracking Array (AGATA) collaboration, is composed of three main blocks: preamplifiers, digitizers and preprocessing electronics. The slow control system contains a custom Linux driver, a dynamic library and a server implementing network services. The digital processing of the data from the GALILEO germanium detectors has demonstrated the capability to achieve an energy resolution of 1.53 per mil at an energy of 1.33 MeV., Comment: 5 pages, 6 figures, preprint version of IEEE Transactions on Nuclear Science paper submitted for the 19th IEEE Real Time Conference
- Published
- 2014
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28. Results on neutrinoless double beta decay of 76Ge from GERDA Phase I
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Agostini, M., Allardt, M., Andreotti, E., Bakalyarov, A. M., Balata, M., Barabanov, I., Heider, M. Barnabé, Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Brudanin, V., Brugnera, R., Budjáš, D., Caldwell, A., Cattadori, C., Chernogorov, A., Cossavella, F., Demidova, E. V., Domula, A., Egorov, V., Falkenstein, R., Ferella, A., Freund, K., Frodyma, N., Gangapshev, A., Garfagnini, A., Gotti, C., Grabmayr, P., Gurentsov, V., Gusev, K., Guthikonda, K. K., Hampel, W., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Ioannucci, L., Csáthy, J. Janicskó, Jochum, J., Junker, M., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Liu, X., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Machado, A. A., Majorovits, B., Maneschg, W., Misiaszek, M., Nemchenok, I., Nisi, S., O'Shaughnessy, C., Pandola, L., Pelczar, K., Pessina, G., Potenza, %F., Pullia, A., Riboldi, S., Rumyantseva, N., Sada, C., Salathe, M., Schmitt, C., Schreiner, J., Schulz, O., Schwingenheuer, B., Schönert, S., Shevchik, E., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Strecker, H., Tarka, M., Ur, C. A., Vasenko, A. A., Volynets, O., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wester, T., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
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Nuclear Experiment ,High Energy Physics - Experiment ,High Energy Physics - Phenomenology - Abstract
Neutrinoless double beta decay is a process that violates lepton number conservation. It is predicted to occur in extensions of the Standard Model of particle physics. This Letter reports the results from Phase I of the GERmanium Detector Array (GERDA) experiment at the Gran Sasso Laboratory (Italy) searching for neutrinoless double beta decay of the isotope 76Ge. Data considered in the present analysis have been collected between November 2011 and May 2013 with a total exposure of 21.6 kgyr. A blind analysis is performed. The background index is about 1.10^{-2} cts/(keV kg yr) after pulse shape discrimination. No signal is observed and a lower limit is derived for the half-life of neutrinoless double beta decay of 76Ge, T_1/2 > 2.1 10^{25} yr (90% C.L.). The combination with the results from the previous experiments with 76Ge yields T_1/2 > 3.0 10^{25} yr (90% C.L.)., Comment: 6 pages, 2 figures
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- 2013
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29. Pulse shape discrimination for GERDA Phase I data
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Agostini, M., Allardt, M., Andreotti, E., Bakalyarov, A. M., Balata, M., Barabanov, I., Heider, M. Barnabe, Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Brudanin, V., Brugnera, R., Budjáš, D., Caldwell, A., Cattadori, C., Chernogorov, A., Cossavella, F., Demidova, E. V., Domula, A., Egorov, V., Falkenstein, R., Ferella, A., Freund, K., Frodyma, N., Gangapshev, A., Garfagnini, A., Gotti, C., Grabmayr, P., Gurentsov, V., Gusev, K., Guthikonda, K. K., Hampel, W., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Ioannucci, L., Csáthy, J. Janicskó, Jochum, J., Junker, M., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Liu, X., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Machado, A. A., Majorovits, B., Maneschg, W., Misiaszek, M., Nemchenok, I., Nisi, S., O'Shaughnessy, C., Pandola, L., Pelczar, K., Pessina, G., Pullia, A., Riboldi, S., Rumyantseva, N., Sada, C., Salathe, M., Schmitt, C., Schreiner, J., Schulz, O., Schwingenheuer, B., Schönert, S., Shevchik, E., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Strecker, H., Tarka, M., Ur, C. A., Vasenko, A. A., Volynets, O., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wester, T., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
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Physics - Instrumentation and Detectors ,Nuclear Experiment - Abstract
The GERDA experiment located at the LNGS searches for neutrinoless double beta (0\nu\beta\beta) decay of ^{76}Ge using germanium diodes as source and detector. In Phase I of the experiment eight semi-coaxial and five BEGe type detectors have been deployed. The latter type is used in this field of research for the first time. All detectors are made from material with enriched ^{76}Ge fraction. The experimental sensitivity can be improved by analyzing the pulse shape of the detector signals with the aim to reject background events. This paper documents the algorithms developed before the data of Phase I were unblinded. The double escape peak (DEP) and Compton edge events of 2.615 MeV \gamma\ rays from ^{208}Tl decays as well as 2\nu\beta\beta\ decays of ^{76}Ge are used as proxies for 0\nu\beta\beta\ decay. For BEGe detectors the chosen selection is based on a single pulse shape parameter. It accepts 0.92$\pm$0.02 of signal-like events while about 80% of the background events at Q_{\beta\beta}=2039 keV are rejected. For semi-coaxial detectors three analyses are developed. The one based on an artificial neural network is used for the search of 0\nu\beta\beta\ decay. It retains 90% of DEP events and rejects about half of the events around Q_{\beta\beta}. The 2\nu\beta\beta\ events have an efficiency of 0.85\pm0.02 and the one for 0\nu\beta\beta\ decays is estimated to be 0.90^{+0.05}_{-0.09}. A second analysis uses a likelihood approach trained on Compton edge events. The third approach uses two pulse shape parameters. The latter two methods confirm the classification of the neural network since about 90% of the data events rejected by the neural network are also removed by both of them. In general, the selection efficiency extracted from DEP events agrees well with those determined from Compton edge events or from 2\nu\beta\beta\ decays., Comment: 18 pages, 27 figures
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- 2013
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30. The background in the neutrinoless double beta decay experiment GERDA
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The GERDA collaboration, Agostini, M., Allardt, M., Andreotti, E., Bakalyarov, A. M., Balata, M., Barabanov, I., Heider, M. Barnabe, Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Brudanin, V., Brugnera, R., Budjas, D., Caldwell, A., Cattadori, C., Chernogorov, A., Cossavella, F., Demidova, E. V., Domula, A., Egorov, V., Falkenstein, R., Ferella, A., Freund, K., Frodyma, N., Gangapshev, A., Garfagnini, A., Gotti, C., Grabmayr, P., Gurentsov, V., Gusev, K., Guthikonda, K. K., Hampel, W., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Ioannucci, L., Csathy, J. Janicsko, Jochum, J., Junker, M., Kihm, T., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knoepfle, K. T., Kochetov, O., Kornoukhov, V. N., Kuzminov, V. V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Liu, X., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Macolino, C., Machado, A. A., Majorovits, B., Maneschg, W., Nemchenok, I., Nisi, S., O'Shaughnessy, C., Palioselitis, D., Pandola, L., Pelczar, K., Pessina, G., Pullia, A., Riboldi, S., Sada, C., Salathe, M., Schmitt, C., Schreiner, J., Schulz, O., Schwingenheuer, B., Schoenert, S., Shevchik, E., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Strecker, H., Tarka, M., Ur, C. A., Vasenko, A. A., Volynets, O., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wester, T., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
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Physics - Instrumentation and Detectors ,High Energy Physics - Experiment - Abstract
The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double beta decay of 76Ge. The signature of the signal is a monoenergetic peak at 2039 keV, the Q-value of the decay, Q_bb. To avoid bias in the signal search, the present analysis does not consider all those events, that fall in a 40 keV wide region centered around Q_bb. The main parameters needed for the neutrinoless double beta decay analysis are described. A background model was developed to describe the observed energy spectrum. The model contains several contributions, that are expected on the basis of material screening or that are established by the observation of characteristic structures in the energy spectrum. The model predicts a flat energy spectrum for the blinding window around Q_bb with a background index ranging from 17.6 to 23.8*10^{-3} counts/(keV kg yr). A part of the data not considered before has been used to test if the predictions of the background model are consistent. The observed number of events in this energy region is consistent with the background model. The background at Q-bb is dominated by close sources, mainly due to 42K, 214Bi, 228Th, 60Co and alpha emitting isotopes from the 226Ra decay chain. The individual fractions depend on the assumed locations of the contaminants. It is shown, that after removal of the known gamma peaks, the energy spectrum can be fitted in an energy range of 200 kev around Q_bb with a constant background. This gives a background index consistent with the full model and uncertainties of the same size.
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31. HEROICA: an Underground Facility for the Fast Screening of Germanium Detectors
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Andreotti, E., Garfagnini, A., Maneschg, W., Barros, N., Benato, G., Brugnera, R., Costa, F., Falkenstein, R., Guthikonda, K. K., Hegai, A., Hemmer, S., Hult, M., Jaenner, K., Kihm, T., Lehnert, B., Liao, H., Lubashevskiy, A., Lutter, G., Marissens, G., Modenese, L., Pandola, L., Reissfelder, M., Sada, C., Salathe, M., Schmitt, C., Schulz, O., Schwingenheuer, B., Turcato, M., Ur, C., von Sturm, K., Wagner, V., and Westermann, J.
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Physics - Instrumentation and Detectors ,Nuclear Experiment - Abstract
An infrastructure to characterize germanium detectors has been designed and constructed at the HADES Underground Research Laboratory, located in Mol (Belgium). Thanks to the 223m overburden of clay and sand, the muon flux is lowered by four orders of magnitude. This natural shield minimizes the exposure of radio-pure germanium material to cosmic radiation resulting in a significant suppression of cosmogenic activation in the germanium detectors. The project has been strongly motivated by a special production of germanium detectors for the GERDA experiment. GERDA, currently collecting data at the Laboratori Nazionali del Gran Sasso of INFN, is searching for the neutrinoless double beta decay of 76Ge. In the near future, GERDA will increase its mass and sensitivity by adding new Broad Energy Germanium (BEGe) detectors. The production of the BEGe detectors is done at Canberra in Olen (Belgium), located about 30km from the underground test site. Therefore, HADES is used both for storage of the crystals over night, during diode production, and for the characterization measurements. A full quality control chain has been setup and tested on the first seven prototype detectors delivered by the manufacturer at the beginning of 2012. The screening capabilities demonstrate that the installed setup fulfills a fast and complete set of measurements on the diodes and it can be seen as a general test facility for the fast screening of high purity germanium detectors. The results are of major importance for a future massive production and characterization chain of germanium diodes foreseen for a possible next generation 1-tonne double beta decay experiment with 76Ge., Comment: Submitted to JINST
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32. The GERDA experiment for the search of 0\nu\beta\beta\ decay in ^{76}Ge
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GERDA Collaboration, Ackermann, K. -H., Agostini, M., Allardt, M., Altmann, M., Andreotti, E., Bakalyarov, A. M., Balata, M., Barabanov, I., Heider, M. Barnabe, Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Brudanin, V., Brugnera, R., Budjas, D., Caldwell, A., Cattadori, C., Chernogorov, A., Chkvorets, O., Cossavella, F., D`Andragora, A., Demidova, E. V., Denisov, A., di Vacri, A., Domula, A., Egorov, V., Falkenstein, R., Ferella, A., Freund, K., Froborg, F., Frodyma, N., Gangapshev, A., Garfagnini, A., Gasparro, J., Gazzana, S., de Orduna, R. Gonzalez, Grabmayr, P., Gurentsov, V., Gusev, K., Guthikonda, K. K., Hampel, W., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Ioannucci, L., Csalty, J. Janicsko, Jochum, J., Junker, M., Kankanyan, R., Kianovsky, S., Kihm, T., Kiko, J., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knapp, M., Knöpfle, K. T., Kochetov, O., Kornoukhov, V. N., Kröninger, K., Kusminov, V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Lenz, D., Liao, H., Lindner, M., Lippi, I., Liu, J., Liu, X., Lubashevskiy, A., Lubsandorzhiev, B., Machado, A. A., Majorovits, B., Maneschg, W., Marissens, G., Mayer, S., Meierhofer, G., Nemchenok, I., Niedermeier, L., Nisi, S., Oehm, J., O'Shaughnessy, C., Pandola, L., Peiffer, P., Pelczar, K., Pullia, A., Riboldi, S., Ritter, F., Alvarez, C. Rossi, Sada, C., Salathe, M., Schmitt, C., Schönert, S., Schreiner, J., Schubert, J., Schulz, O., Schwan, U., Schwingenheuer, B., Seitz, H., Shevchik, E., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Stelzer, F., Strecker, H., Tarka, M., Trunk, U., Ur, C. A., Vasenko, A. A., Vogt, S., Volynets, O., von Sturm, K., Wagner, V., Walter, M., Wegmann, A., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
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Physics - Instrumentation and Detectors ,High Energy Physics - Experiment ,Nuclear Experiment - Abstract
The GERDA collaboration is performing a search for neutrinoless double beta decay of ^{76}Ge with the eponymous detector. The experiment has been installed and commissioned at the Laboratori Nazionali del Gran Sasso and has started operation in November 2011. The design, construction and first operational results are described, along with detailed information from the R&D phase., Comment: 31 pages, 23 figures, submitted to EPJC
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- 2012
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33. Measurement of the half-life of the two-neutrino double beta decay of Ge-76 with the Gerda experiment
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GERDA Collaboration, Agostini, M., Allardt, M., Andreotti, E., Bakalyarov, A. M., Balata, M., Barabanov, I., Heider, M. Barnabe, Barros, N., Baudis, L., Bauer, C., Becerici-Schmidt, N., Bellotti, E., Belogurov, S., Belyaev, S. T., Benato, G., Bettini, A., Bezrukov, L., Bode, T., Brudanin, V., Brugnera, R., Budjas, D., Caldwell, A., Cattadori, C., Chernogorov, A., Cossavella, F., Demidova, E. V., Denisov, A., Domula, A., Egorov, V., Falkenstein, R., Ferella, A. D., Freund, K., Froborg, F., Frodyma, N., Gangapshev, A., Garfagnini, A., Gazzana, S., Grambayr, P., Gurentsov, V., Gusev, K., Guthikonda, K. K., Hampel, W., Hegai, A., Heisel, M., Hemmer, S., Heusser, G., Hofmann, W., Hult, M., Inzhechik, L. V., Ioannucci, L., Csathy, J. Janicsko, Jochum, J., Junker, M., Kianovsky, S., Kirpichnikov, I. V., Kirsch, A., Klimenko, A., Knoepfle, K. T., Kochetov, O., Kornoukhov, V. N., Kusminov, V., Laubenstein, M., Lazzaro, A., Lebedev, V. I., Lehnert, B., Liao, H. Y., Lindner, M., Lippi, I., Liu, X., Lubashevskiy, A., Lubsandorzhiev, B., Lutter, G., Machado, A. A., Majorovits, B., Maneschg, W., Nemchenok, I., Nisi, S., O'Shaughnessy, C., Pandola, L., Pelczar, K., Peraro, L., Pullia, A., Riboldi, S., Ritter, F., Sada, C., Salathe, M., Schmitt, C., Schoenert, S., Schreiner, J., Schulz, O., Schwingenheuer, B., Shevchik, E., Shirchenko, M., Simgen, H., Smolnikov, A., Stanco, L., Strecker, H., Tarka, M., Ur, C. A., Vasenko, A. A., Volynets, O., von Sturm, K., Walter, M., Wegmann, A., Wojcik, M., Yanovich, E., Zavarise, P., Zhitnikov, I., Zhukov, S. V., Zinatulina, D., Zuber, K., and Zuzel, G.
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Nuclear Experiment ,High Energy Physics - Experiment - Abstract
The primary goal of the GERmanium Detector Array (Gerda) experiment at the Laboratori Nazionali del Gran Sasso of INFN is the search for the neutrinoless double beta decay of Ge-76. High-purity germanium detectors made from material enriched in Ge-76 are operated directly immersed in liquid argon, allowing for a substantial reduction of the background with respect to predecessor experiments. The first 5.04 kg yr of data collected in Phase I of the experiment have been analyzed to measure the half-life of the neutrino-accompanied double beta decay of Ge-76. The observed spectrum in the energy range between 600 and 1800 keV is dominated by the double beta decay of Ge-76. The half-life extracted from Gerda data is T(1/2) = (1.84 +0.14 -0.10) 10^{21} yr., Comment: 14 pages, 2 figures, submitted to J. Phys. G: Nucl. Part. Phys
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- 2012
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34. High-spin structure in $^{40}$K
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Söderström, P. -A., Recchia, F., Nyberg, J., Gadea, A., Lenzi, S. M., Poves, A., Ataç, A., Aydin, S., Bazzacco, D., Bednarczyk, P., Bellato, M., Birkenbach, B., Bortolato, D., Boston, A. J., Boston, H. C., Bruyneel, B., Bucurescu, D., Calore, E., Cederwall, B., Charles, L., Chavas, J., Colosimo, S., Crespi, F. C. L., Cullen, D. M., de Angelis, G., Désesquelles, P., Dosme, N., Duchêne, G., Eberth, J., Farnea, E., Filmer, F., Görgen, A., Gottardo, A., Grębosz, J., Gulmini, M., Hess, H., Hughes, T. A., Jaworski, G., Jolie, J., Joshi, P., Judson, D. S., Jungclaus, A., Karkour, N., Karolak, M., Kempley, R. S., Khaplanov, A., Korten, W., Ljungvall, J., Lunardi, S., Maj, A., Maron, G., Męczyński, W., Mengoni, D., Michelagnoli, C., Molini, P., Napoli, D. R., Nolan, P. J., Norman, M., Obertelli, A., Podolyak, Zs., Pullia, A., Quintana, B., Redon, N., Regan, P. H., Reiter, P., Robinson, A. P., Şahin, E., Simpson, J., Salsac, M. D., Smith, J. F., Stézowski, O., Theisen, Ch., Tonev, D., Unsworth, C., Ur, C. A., Valiente-Dobón, J. J., and Wiens, A.
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Nuclear Experiment - Abstract
High-spin states of $^{40}$K have been populated in the fusion-evaporation reaction $^{12}$C($^{30}$Si,np)$^{40}$K and studied by means of $\gamma$-ray spectroscopy techniques using one AGATA triple cluster detector, at INFN - Laboratori Nazionali di Legnaro. Several new states with excitation energy up to 8 MeV and spin up to $10^-$ have been discovered. These new states are discussed in terms of J=3 and T=0 neutron-proton hole pairs. Shell-model calculations in a large model space have shown a good agreement with the experimental data for most of the energy levels. The evolution of the structure of this nucleus is here studied as a function of excitation energy and angular momentum., Comment: 23 pages, 5 figures, submitted to Phys. Rev. C
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- 2012
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35. Response of AGATA Segmented HPGe Detectors to Gamma Rays up to 15.1 MeV
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Crespi, F. C. L., Avigo, R., Camera, F., Akkoyun, S., Atac, A., Bazzacco, D., Bellato, M., Benzoni, G., Blasi, N., Bortolato, D., Bottoni, S., Bracco, A., Brambilla, S., Bruyneel, B., Cerutia, S., Ciemala, M., Coelli, S., Eberth, J., Fanin, C., Farnea, E., Gadea, A., Giaz, A., Gottardo, A., Hess, H., Kmiecik, M., Leoni, S., Maj, A., Mengoni, D., Michelagnoli, C., Million, B., Montanari, D., Pellegri, L., Recchia, F., Reiter, P., Riboldi, S., Ur, C. A., Vandone, V., Valiente-Dobon, J. J., Wieland, O., Wiens, A., and Collaboration, The AGATA
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Nuclear Experiment ,81V35 - Abstract
The response of AGATA segmented HPGe detectors to gamma rays in the energy range 2-15 MeV was measured. The 15.1 MeV gamma rays were produced using the reaction d(11B,ng)12C at Ebeam = 19.1 MeV, while gamma-rays between 2 to 9 MeV were produced using an Am-Be-Fe radioactive source. The energy resolution and linearity were studied and the energy-to-pulse-height conversion resulted to be linear within 0.05%. Experimental interaction multiplicity distributions are discussed and compared with the results of Geant4 simulations. It is shown that the application of gamma-ray tracking allows a suppression of background radiation following neutron capture by Ge nuclei. Finally the Doppler correction for the 15.1 MeV gamma line, performed using the position information extracted with Pulse-shape Analysis, is discussed., Comment: 10 pages, 11 figures
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- 2012
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36. AGATA - Advanced Gamma Tracking Array
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Akkoyun, S., Algora, A., Alikhani, B., Ameil, F., de Angelis, G., Arnold, L., Astier, A., Ataç, A., Aubert, Y., Aufranc, C., Austin, A., Aydin, S., Azaiez, F., Badoer, S., Balabanski, D. L., Barrientos, D., Baulieu, G., Baumann, R., Bazzacco, D., Beck, F. A., Beck, T., Bednarczyk, P., Bellato, M., Bentley, M. A., Benzoni, G., Berthier, R., Berti, L., Beunard, R., Bianco, G. Lo, Birkenbach, B., Bizzeti, P. G., Bizzeti-Sona, A. M., Blanc, F. Le, Blasco, J. M., Blasi, N., Bloor, D., Boiano, C., Borsato, M., Bortolato, D., Boston, A. J., Boston, H. C., Bourgault, P., Boutachkov, P., Bouty, A., Bracco, A., Brambilla, S., Brawn, I. P., Brondi, A., Broussard, S., Bruyneel, B., Bucurescu, D., Burrows, I., Bürger, A., Cabaret, S., Cahan, B., Calore, E., Camera, F., Capsoni, A., Carrió, F., Casati, G., Castoldi, M., Cederwall, B., Cercus, J. -L., Chambert, V., Chambit, M. El, Chapman, R., Charles, L., Chavas, J., Clément, E., Cocconi, P., Coelli, S., Coleman-Smith, P. J., Colombo, A., Colosimo, S., Commeaux, C., Conventi, D., Cooper, R. J., Corsi, A., Cortesi, A., Costa, L., Crespi, F. C. L., Cresswell, J. R., Cullen, D. M., Curien, D., Czermak, A., Delbourg, D., Depalo, R., Descombes, T., Désesquelles, P., Detistov, P., Diarra, C., Didierjean, F., Dimmock, M. R., Doan, Q. T., Domingo-Pardo, C., Doncel, M., Dorangeville, F., Dosme, N., Drouen, Y., Duchêne, G., Dulny, B., Eberth, J., Edelbruck, P., Egea, J., Engert, T., Erduran, M. N., Ertürk, S., Fanin, C., Fantinel, S., Farnea, E., Faul, T., Filliger, M., Filmer, F., Finck, Ch., de France, G., Gadea, A., Gast, W., Geraci, A., Gerl, J., Gernhäuser, R., Giannatiempo, A., Giaz, A., Gibelin, L., Givechev, A., Goel, N., González, V., Gottardo, A., Grave, X., Grȩbosz, J., Griffiths, R., Grint, A. N., Gros, P., Guevara, L., Gulmini, M., Görgen, A., Ha, H. T. M., Habermann, T., Harkness, L. J., Harroch, H., Hauschild, K., He, C., Hernández-Prieto, A., Hervieu, B., Hess, H., Hüyük, T., Ince, E., Isocrate, R., Jaworski, G., Johnson, A., Jolie, J., Jones, P., Jonson, B., Joshi, P., Judson, D. S., Jungclaus, A., Kaci, M., Karkour, N., Karolak, M., Kaşkaş, A., Kebbiri, M., Kempley, R. S., Khaplanov, A., Klupp, S., Kogimtzis, M., Kojouharov, I., Korichi, A., Korten, W., Kröll, Th., Krücken, R., Kurz, N., Ky, B. Y., Labiche, M., Lafay, X., Lavergne, L., Lazarus, I. H., Leboutelier, S., Lefebvre, F., Legay, E., Legeard, L., Lelli, F., Lenzi, S. M., Leoni, S., Lermitage, A., Lersch, D., Leske, J., Letts, S. C., Lhenoret, S., Lieder, R. M., Linget, D., Ljungvall, J., Lopez-Martens, A., Lotodé, A., Lunardi, S., Maj, A., van der Marel, J., Mariette, Y., Marginean, N., Marginean, R., Maron, G., Mather, A. R., Mȩczyński, W., Mendéz, V., Medina, P., Melon, B., Menegazzo, R., Mengoni, D., Merchan, E., Mihailescu, L., Michelagnoli, C., Mierzejewski, J., Milechina, L., Million, B., Mitev, K., Molini, P., Montanari, D., Moon, S., Morbiducci, F., Moro, R., Morrall, P. S., Möller, O., Nannini, A., Napoli, D. R., Nelson, L., Nespolo, M., Ngo, V. L., Nicoletto, M., Nicolini, R., Noa, Y. Le, Nolan, P. J., Norman, M., Nyberg, J., Obertelli, A., Olariu, A., Orlandi, R., Oxley, D. C., Özben, C., Ozille, M., Oziol, C., Pachoud, E., Palacz, M., Palin, J., Pancin, J., Parisel, C., Pariset, P., Pascovici, G., Peghin, R., Pellegri, L., Perego, A., Perrier, S., Petcu, M., Petkov, P., Petrache, C., Pierre, E., Pietralla, N., Pietri, S., Pignanelli, M., Piqueras, I., Podolyak, Z., Pouhalec, P. Le, Pouthas, J., Pugnére, D., Pucknell, V. F. E., Pullia, A., Quintana, B., Raine, R., Rainovski, G., Ramina, L., Rampazzo, G., La Rana, G., Rebeschini, M., Recchia, F., Redon, N., Reese, M., Reiter, P., Regan, P. H., Riboldi, S., Richer, M., Rigato, M., Rigby, S., Ripamonti, G., Robinson, A. P., Robin, J., Roccaz, J., Ropert, J. -A., Rossé, B., Alvarez, C. Rossi, Rosso, D., Rubio, B., Rudolph, D., Saillant, F., Şahin, E., Salomon, F., Salsac, M. -D., Salt, J., Salvato, G., Sampson, J., Sanchis, E., Santos, C., Schaffner, H., Schlarb, M., Scraggs, D. P., Seddon, D., Şenyiğit, M., Sigward, M. -H., Simpson, G., Simpson, J., Slee, M., Smith, J. F., Sona, P., Sowicki, B., Spolaore, P., Stahl, C., Stanios, T., Stefanova, E., Stézowski, O., Strachan, J., Suliman, G., Söderström, P. -A., Tain, J. L., Tanguy, S., Tashenov, S., Theisen, Ch., Thornhill, J., Tomasi, F., Toniolo, N., Touzery, R., Travers, B., Triossi, A., Tripon, M., Tun-Lanoë, K. M. M., Turcato, M., Unsworth, C., Ur, C. A., Valiente-Dobon, J. J., Vandone, V., Vardaci, E., Venturelli, R., Veronese, F., Veyssiere, Ch., Viscione, E., Wadsworth, R., Walker, P. M., Warr, N., Weber, C., Weisshaar, D., Wells, D., Wieland, O., Wiens, A., Wittwer, G., Wollersheim, H. J., Zocca, F., Zamfir, N. V., Ziȩbliński, M., and Zucchiatti, A.
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Physics - Instrumentation and Detectors ,Nuclear Experiment - Abstract
The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation gamma-ray spectrometer. AGATA is based on the technique of gamma-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a gamma ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realization of gamma-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly-segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterization of the crystals was measured and compared with detector-response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximize its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer., Comment: This version contains a correction of a typing error in the caption of Fig. 2. The DOI to the article published in Nucl. Instr. Meth A was also added
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- 2011
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37. Characterization of a broad energy germanium detector and application to neutrinoless double beta decay search in Ge-76
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Agostini, M., Bellotti, E., Brugnera, R., Cattadori, C. M., D'Andragora, A., di Vacri, A., Garfagnini, A., Laubenstein, M., Pandola, L., and Ur, C. A.
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Physics - Instrumentation and Detectors ,High Energy Physics - Experiment ,Nuclear Experiment - Abstract
The performance of a 630g commercial broad energy germanium (BEGe) detector has been systematically investigated. Energy resolution, linearity, stability vs. high-voltage (HV) bias, thickness and uniformity of dead layers have been measured and found to be excellent. Special attention has been dedicated to the study of the detector response as a function of bias HV. The nominal depletion voltage being 3000V, the detector under investigation shows a peculiar behavior for biases around 2000V: in a narrow range of about 100V the charge collection is strongly reduced. The detector seems to be composed by two parts: a small volume around the HV contact where charges are efficiently collected as at higher voltage, and a large volume where charges are poorly collected. A qualitative explanation of this behavior is presented. An event-by-event pulse shape analysis based on A/E (maximum amplitude of the current pulse over the total energy released in the detector) has been applied to events in different energy regions and found very effective in rejecting non localized events. In conclusion, BEGe detectors are excellent candidates for the second phase of GERDA, an experiment devoted to neutrinoless double beta decay of Ge-76., Comment: Submitted to JINST, 17 pages, 11 figures. Companion paper of arXiv:1012.4300
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- 2010
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38. Signal modeling of high-purity Ge detectors with a small read-out electrode and application to neutrinoless double beta decay search in Ge-76
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Agostini, M., Ur, C. A., Budjáš, D., Bellotti, E., Brugnera, R., Cattadori, C. M., di Vacri, A., Garfagnini, A., Pandola, L., and Schönert, S.
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Physics - Instrumentation and Detectors ,Nuclear Experiment - Abstract
The GERDA experiment searches for the neutrinoless double beta decay of Ge-76 using high-purity germanium detectors enriched in Ge-76. The analysis of the signal time structure provides a powerful tool to identify neutrinoless double beta decay events and to discriminate them from gamma-ray induced backgrounds. Enhanced pulse shape discrimination capabilities of "Broad Energy Germanium" detectors with a small read-out electrode have been recently reported. This paper describes the full simulation of the response of such a detector, including the Monte Carlo modeling of radiation interaction and subsequent signal shape calculation. A pulse shape discrimination method based on the ratio between the maximum current signal amplitude and the event energy applied to the simulated data shows quantitative agreement with the experimental data acquired with calibration sources. The simulation has been used to study the survival probabilities of the decays which occur inside the detector volume and are difficult to assess experimentally. Such internal decay events are produced by the cosmogenic radio-isotopes Ge-68 and Co-60 and the neutrinoless double beta decay of Ge-76. Fixing the experimental acceptance of the double escape peak of the 2.614 MeV photon to 90%, the estimated survival probabilities at Qbb = 2.039 MeV are (86+-3)% for Ge-76 neutrinoless double beta decays, (4.5+-0.3)% for the Ge-68 daughter Ga-68, and (0.9+0.4-0.2)% for Co-60 decays., Comment: 27 pages, 17 figures. v2: fixed typos and references. Submitted to JINST
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- 2010
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39. Transition probabilities in the X(5) candidate $^{122}$Ba
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Bizzeti, P. G., Bizzeti-Sona, A. M., Tonev, D., Giannatiempo, A., Ur, C. A., Dewald, A., Melon, B., Michelagnoli, C., Petkov, P., Bazzacco, D., Costin, A., de Angelis, G., Della Vedova, F., Fantuzi, M., Farnea, E., Fransen, C., Gadea, A., Lenzi, S., Lunardi, S., Marginean, N., Marginean, R., Menegazzo, R., Mengoni, D., Moeller, O., Nannini, A., Napoli, D. R., Nespolo, M., Pavan, P., Perego, A., Petrache, C. M., Pietralla, N., Alvarez, C. Rossi, and Sona, P.
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Nuclear Experiment - Abstract
To investigate the possible X(5) character of 122Ba, suggested by the ground state band energy pattern, the lifetimes of the lowest yrast states of 122Ba have been measured, via the Recoil Distance Doppler-Shift method. The relevant levels have been populated by using the 108Cd(16O,2n)122Ba and the 112Sn(13C,3n)122Ba reactions. The B(E2) values deduced in the present work are compared to the predictions of the X(5) model and to calculations performed in the framework of the IBA-1 and IBA-2 models.
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- 2010
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40. Observation of isotonic symmetry for enhanced quadrupole collectivity in neutron-rich 62,64,66Fe isotopes at N=40
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Rother, W., Dewald, A., Iwasaki, H., Lenzi, S. M., Starosta, K., Bazin, D., Baugher, T., Brown, B. A., Crawford, H. L., Fransen, C., Gade, A., Ginter, T. N., Glasmacher, T., Grinyer, G. F., Hackstein, M., Ilie, G., Jolie, J., McDaniel, S., Miller, D., Petkov, P., Pissulla, Th., Ratkiewicz, A., Ur, C. A., Voss, P., Walsh, K. A., Weisshaar, D., and Zell, K. -O.
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Nuclear Experiment ,Nuclear Theory - Abstract
The transition rates for the 2_{1}^{+} states in 62,64,66Fe were studied using the Recoil Distance Doppler-Shift technique applied to projectile Coulomb excitation reactions. The deduced E2 strengths illustrate the enhanced collectivity of the neutron-rich Fe isotopes up to N=40. The results are interpreted by the generalized concept of valence proton symmetry which describes the evolution of nuclear structure around N=40 as governed by the number of valence protons with respect to Z~30. The deformation suggested by the experimental data is reproduced by state-of-the-art shell calculations with a new effective interaction developed for the fpgd valence space., Comment: 4 pages, 2 figures
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- 2010
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41. Spectroscopy of Neutron-Rich 168,170Dy: Yrast Band Evolution Close to the NpNn Valence Maximum
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Söderström, P. -A., Nyberg, J., Regan, P. H., Algora, A., de Angelis, G., Ashley, S. F., Aydin, S., Bazzacco, D., Casperson, R. J., Catford, W. N., Cederkäll, J., Chapman, R., Corradi, L., Fahlander, C., Farnea, E., Fioretto, E., Freeman, S. J., Gadea, A., Gelletly, W., Gottardo, A., Grodner, E., He, C. Y., Jones, G. A., Keyes, K., Labiche, M., Liang, X., Liu, Z., Lunardi, S., Mărginean, N., Mason, P., Menegazzo, R., Mengoni, D., Montagnoli, G., Napoli, D., Ollier, J., Pietri, S., Podolyák, Zs., Pollarolo, G., Recchia, F., Şahin, E., Scarlassara, F., Silvestri, R., Smith, J. F., Spohr, K. -M., Steer, S. J., Stefanini, A. M., Szilner, S., Thompson, N. J., Tveten, G. M., Ur, C. A., Valiente-Dobón, J. J., Werner, V., Williams, S. J., Xu, F. R., and Zhu, J. Y.
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Nuclear Experiment - Abstract
The yrast sequence of the neutron-rich dysprosium isotope 168Dy has been studied using multi-nucleon transfer reactions following collisions between a 460-MeV 82Se beam and a 170Er target. The reaction products were identified using the PRISMA magnetic spectrometer and the gamma rays detected using the CLARA HPGe-detector array. The 2+ and 4+ members of the previously measured ground state rotational band of 168Dy have been confirmed and the yrast band extended up to 10+. A tentative candidate for the 4+ to 2+ transition in 170Dy was also identified. The data on these nuclei and on the lighter even-even dysprosium isotopes are interpreted in terms of Total Routhian Surface calculations and the evolution of collectivity in the vicinity of the proton-neutron valence product maximum is discussed., Comment: 15 pages, 7 figures, submitted to Phys. Rev. C
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- 2009
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42. Spectroscopic studies of Dy-168,170 using CLARA and PRISMA
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Söderström, P. -A., Nyberg, J., Regan, P. H., Algora, A., de Angelis, G., Ashley, S. F., Aydin, S., Bazzacco, D., Casperson, R. J., Catford, W. N., Cederkäll, J., Chapman, R., Corradi, L., Fahlander, C., Farnea, E., Freeman, S. J., Gadea, A., Gelletly, W., Grodner, E., He, C. Y., Jones, G. A., Keyes, K., Labiche, M., Liang, X., Liu, Z., Lunardi, S., Marginean, N., Menegazzo, R., Mengoni, D., Napoli, D., Ollier, J., Pietri, S., Podolyàk, Zs., Recchia, F., Sahin, E., Smith, J. F., Spohr, K. M., Steer, S. J., Stefanini, A., Thompson, N. J., Tveten, G., Ur, C. A., Valiente-Dóbon, J. J., Werner, V., and Williams, S. J.
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Nuclear Experiment - Abstract
Preliminary results from an experiment aiming at Dy-170. Submitted to the LNL Annual Report 2008., Comment: 2 pages, 4 figures, Submitted to the LNL Annual Report 2008
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- 2009
43. Structure of N=56 isotones with 36≤Z≤42 protons
- Author
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Wiśniewski, J., primary, Urban, W., additional, Rząca-Urban, T., additional, Sieja, K., additional, Blanc, A., additional, Jentschel, M., additional, Micheagnoli, C., additional, Mutti, P., additional, Köster, U., additional, de France, G., additional, Simpson, G. S., additional, and Ur, C. A., additional
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- 2023
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44. Low-spin excitations in Zr95
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Rząca-Urban, T., primary, Urban, W., additional, Blanc, A., additional, Jentschel, M., additional, Mutti, P., additional, Köster, U., additional, de France, G., additional, Simpson, G. S., additional, and Ur, C. A., additional
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- 2023
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45. Multinucleon transfer reactions in closed-shell nuclei
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Szilner, S., Ur, C. A., Corradi, L., Marginean, N., Pollarolo, G., Stefanini, A. M., Beghini, S., Behera, B. R., Fioretto, E., Gadea, A., Guiot, B., Latina, A., Mason, P., Montagnoli, G., Scarlassara, F., Trotta, M., de Angelis, G., Della Vedova, F., Farnea, E., Haas, F., Lenzi, S., Lunardi, S., Marginean, R., Menegazzo, R, Napoli, D. R., Nespolo, M., Pokrovsky, I. V., Recchia, F., Romoli, M., Salsac, M. -D., Soic, N., and Valiente-Dobon, J. J.
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Nuclear Experiment - Abstract
Multinucleon transfer reactions in 40Ca+96Zr and 90Zr+208Pb have been measured at energies close to the Coulomb barrier in a high resolution gamma-particle coincidence experiment. The large solid angle magnetic spectrometer PRISMA coupled to the CLARA gamma-array has been employed. Trajectory reconstruction has been applied for the complete identification of transfer products. Mass and charge yields, total kinetic energy losses, gamma transitions of the binary reaction partners, and comparison of data with semiclassical calculations are reported. Specific transitions in 95Zr populated in one particle transfer channels are discussed in terms of particle-phonon couplings. The gamma decays from states in 42Ca in the excitation energy region expected from pairing vibrations are also observed., Comment: 10 pages, 9 figures
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- 2007
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46. Shell-model description of N ~ Z 1f7/2 nuclei
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Brandolini, F. and Ur, C. A.
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Nuclear Theory - Abstract
For natural parity states of several odd-A nuclei a comparison of shell model calculations in the full pf configuration space with the Nilsson diagram and particle-rotor predictions shows that prolate strong coupling applies at low excitation energy, revealing multi-quasiparticle rotational bands and, in some cases, bandcrossings. Moreover, ground state bands experience a change from collective to non-collective regime, approaching the termination. Similar features are observed in the even-even nuclei. In the even-even N=Z nuclei evidence of the vibrational gamma-band is found. A review of non-natural parity structures is furthermore presented., Comment: 18 pages, 24 figures
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- 2004
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47. Transition rates and nuclear structure changes in mirror nuclei 47Cr and 47V
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Tonev, D., Petkov, P., Dewald, A., Klug, T., von Brentano, P., Andrejtscheff, W., Lenzi, S. M., Napoli, D. R., Marginean, N., Brandolini, F., Ur, C. A., Axiotis, M., Bizzeti, P. G., and Bizzeti-Sona, A.
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Nuclear Experiment - Abstract
Lifetime measurements in the mirror nuclei 47Cr and 47V were performed by means of the Doppler-shift attenuation method using the multidetector array EUROBALL, in conjunction with the ancillary detectors ISIS and the Neutron Wall. The determined transition strengths in the yrast cascades are well described by full pf shell model calculations., Comment: Latex2e, 11 pages, 3 figures
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- 2002
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48. g factor of the 12+174K-isomer in 12+174W
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Rocchini, M., Nannini, A., Benzoni, G., Vigezzi, E., Melon, B., John, P. R., Bottoni, S., Ceruti, S., Avigo, R., Sona, P., Ur, C. A., Bazzacco, D., Blasi, N., Bocchi, G., Bracco, A., Camera, F., Capra, S., Crespi, F. C. L., Gamba, E. R., Georgiev, G., Giaz, A., Gottardo, A., Leoni, S., Menegazzo, R., Mengoni, D., Michelagnoli, C., Million, B., Modamio, V., Morales, A. I., Napoli, D. R., Ottanelli, M., Pellegri, L., Perego, A., Valiente-Dobón, J. J., and Wieland, O.
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- 2020
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49. Band termination in the N=Z Odd-Odd Nucleus 46V
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Lenzi, S. M., Napoli, D. R., Ur, C. A., Bazzacco, D., Brandolini, F., Cameron, J. A., Caurier, E., de Angelis, G., De Poli, M., Farnea, E., Gadea, A., Hankonen, S., Lunardi, S., Martinez-Pinedo, G., Podolyak, Zs., Poves, A., Alvarez, C. Rossi, Sanchez-Solano, J., and Somacal, H.
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Nuclear Experiment - Abstract
High spin states in the odd-odd N=Z nucleus 46V have been identified. At low spin, the T=1 isobaric analogue states of 46Ti are established up to I = 6+. Other high spin states, including the band terminating state, are tentatively assigned to the same T=1 band. The T=0 band built on the low-lying 3+ isomer is observed up to the 1f7/2-shell termination at I=15. Both signatures of a negative parity T=0 band are observed up to the terminating states at I = 16- and I = 17-, respectively. The structure of this band is interpreted as a particle-hole excitation from the 1d3/2 shell. Spherical shell model calculations are found to be in excellent agreement with the experimental results., Comment: 5 pages, 4 figures
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- 1999
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50. Effective Z evaluation using monoenergetic gamma rays and neural networks
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Turturica, G. V., Iancu, V., Pappalardo, A., Söderström, P.-A., Açıksöz, E., Balabanski, D. L., Capponi, L., Constantin, P., Fugaru, V., Guardo, G. L., Ilie, M., Ilie, S., Iovea, M., Lattuada, D., Nichita, D., Petruse, T., Spataru, A., and Ur, C. A.
- Published
- 2020
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