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El texto completo de este trabajo no se encuentra disponible por no haber sido facilitado aún por su autor, por restricciones de copyright, o por no existir una versión digital, Passive dosimetry with radiochromic films is widely used in proton radiotherapy, both in clinical and scientific environments, thanks to its simplicity, high spatial resolution and dose-rate independence. However, film under-response for low-energy protons, the so-called linear-energy transfer (LET) quenching, must be accounted and corrected for. We perform a meta-analysis on existing film under-response data with EBT, EBT2 and EBT3 GAFchromic (TM) films and provide a common framework to integrate it, based on the calculation of dose-averaged LET in the active layer of the films. We also report on direct measurements with the 10 MeV proton beam at the Center for Microanalysis of Materials (CMAM) for EBT2, EBT3 and unlaminated EBT3 films, focusing on the 20-80 keV mu m(-1) LET range, where previous data was scarce. Measured film relative efficiency (RE) values are in agreement with previously reported data from the literature. A model on film RE constructed with combined literature and own experimental values in the 5-80 keV mu m(-1) LET range is presented, supporting the hypothesis of a linear decrease of RE with LET, with no remarkable differences between the three types of films analyzed., Comunidad de Madrid, Ministerio de Ciencia e Innovación (España), European Regional Funds, Union Europea. H2020, Universidad Complutense de Madrid, Instituto de Salud Carlos III, Pro CNIC Foundation, Centros de Excelencia Severo Ochoa, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

©2015 American Physical Society. Artículo firmado por 21 autores. B.B. would like to acknowledge helpful discussions with S. Frauendorf and A. O. Macchiavelli. Figures 1(a), 4, and 5 were created using the LEVELSCHEME scientific figure preparation system [70]. This project was funded by the National Science Foundation through Grants No. PHY0822648 and No. PHY0758100 and supported by EU 6th Framework program (Integrating Infrastructure Initiative-Transnational Access) Contract No. 506065 (EURONS), the Spanish MINECO via FPA-2013-41267-P, and by the Academy of Finland under the Centre of Excellence Programme 2006-2011 (nuclear and accelerator based physics program at JYFL). B.B. acknowledges support from the U.S. Department of Energy and Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344., Several new subnanosecond lifetimes were measured in Pd-109 using the fast-timing beta gamma gamma (t) method. Fission fragments of the A = 109 mass chain were produced by bombarding natural uranium with 30 MeV protons at the Jyvaskyla Ion Guide Isotope Separator On-Line (IGISOL) facility. Lifetimes were obtained for excited states in Pd-109 populated following beta decay of Rh-109. The new lifetimes provide some insight into the evolution of nuclear structure in this mass region. In particular, the distinct structure of the two low-lying 7/2(+) states occurring systematically across the Pd isotopic chain is supported by the new lifetime measurements. The available nuclear data indicate a sudden increase in deformation at N = 60 which is related to the strong p-n interaction between pi g(9/2) and vg(7/2) valence nucleons expected in this region., Unión Europea. FP6, Ministerio de Economía y Competitividad (MINECO), National Science Foundation, EU Integrating Infrastructure Initiative–Transnational Access, Academy of Finland under the Centre of Excellence Programme, U.S. Department of Energy, Lawrence Livermore National Laboratory, Sección Deptal. de Arquitectura de Computadores y Automática (Físicas), Fac. de Ciencias Físicas, TRUE, pub

©2016 American Physical Society. Artículo firmado por más de 10 autores. This work is supported by NuPNET and the German ministry of education and research (BMBF) under Grants No. 05P12RDCIA, No. 05P12RDNUP, and No. 05P12PKNUF; by ILL; and by HIC for FAIR. Also supported by the UK Science and Technology Facilities Council and the UK National Measurement Office. The authors appreciate the support of several services at ILL and LPSC., Background: Lifetimes of nuclear excited states in fission fragments have been studied in the past following isotope separation, thus giving access mainly to the fragments' daughters and only to long-lived isomeric states in the primary fragments. For the first time now, short-lived excited states in the primary fragments, produced in neutron-induced prompt fission of U-235 and Pu-241, were studied within the EXILL&FATIMA campaign at the intense neutron-beam facility of the Institute Laue-Langevin in Grenoble. Purpose: We aim to investigate the quadrupole collective properties of neutron-rich even-even Xe-138,Xe-140,Xe-142 isotopes lying between the double shell closure N = 82 and Z = 50 and a deformed region with octupole collectivity. Method: The gamma rays emitted from the excited fragments were detected with a mixed array consisting of 8 HPGe EXOGAM Clover detectors (EXILL) and 16 LaBr3(Ce) fast scintillators (FATIMA). The detector system has the unique ability to select the interesting fragment making use of the high resolution of the HPGe detectors and determine subnanosecond lifetimes using the fast scintillators. For the analysis the generalized centroid difference method was used. Results: We show that quadrupole collectivity increases smoothly with increasing neutron number above the closed N = 82 neutron shell. Our measurements are complemented by state-of-the-art theory calculations based on shell-model descriptions. Conclusions: The observed smooth increase in quadrupole collectivity is similar to the evolution seen in the measured masses of the xenon isotopic chain and is well reproduced by theory. This behavior is in contrast to higher Z even-even nuclei where abrupt change in deformation occurs around N = 90., NuPNET, German ministry of education and research (BMBF), ILL, HIC for FAIR, UK Science and Technology Facilities Council, UK National Measurement Office, LPSC, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

©2016 American Physical Society. Artículo publicado por más de 10 autores. This work was supported in part by GSI (F&E, DR-ZUBE), Bundesministerium fur Bildung und Forschung (BMBF) (06DR134I, 05P09CRFN5, 05P12RDFN8, and 05P15RDFN1), the Hemholtz Association Germany through the Nuclear Astrophysics Virtual Institute (NAVI, Grant No. VH-VI-417), the Helmholtz Association Detector Technology and Systems Platform, the Spanish Research funding agency under projects FPA2012-32443, FPA2013-41267-P, and FPA2013-47831-C2-1-P, the Swedish Research Council, HIC for FAIR and the TU Darmstadt-GSI cooperation contract, the Portuguese FCT project PTDC/FIS/103902/2008, UK STFC under grants ST/E500651/1 and ST/F011989/1, US NSF Grant No. 1415656, and US DOE Grant No. DE-FG02-08ER41533., Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N-20,N-21 are reported. Relativistic N-20,N-21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the N-19(n,gamma)N-20 and N-20(n,gamma)N-21 excitation functions and thermonuclear reaction rates have been determined. The N-19(n,gamma)N-20 rate is up to a factor of 5 higher at T < 1 GK with respect to previous theoretical calculations, leading to a 10% decrease in the predicted fluorine abundance., Ministerio de Economía y Competitividad (MINECO), GSI (FE, DR-ZUBE), Bundesministerium fur Bildung und Forschung (BMBF), Helmholtz Association Detector Technology and Systems Platform, Hemholtz Association Germany through Nuclear Astrophysics Virtual Institute (NAVI), Swedish Research Council, HIC for FAIR, TU Darmstadt-GSI, Portuguese FCT project, UK STFC, US NSF, US DOE, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© Amer Physical Soc 2015. Firmado por 26 autores. This work has been funded by FWO-Vlaanderen (Belgium), by GOA/2010/010 (BOF KU Leuven), by the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12), by the European Commission within the Seventh Framework Programme through I3-ENSAR (Contract No. RII3-CT-2010-262010). This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Award No. DE-FG02-94-ER40834, by Spanish MINECO via Project No. FPA2010-17142, by the Slovak grant agency VEGA (Contract No. 2/0121/14), and by the Slovak Research and Development Agency (Contract No. APVV-0177-11)., The low-energy structure of the neutron-rich nucleus Ni-68 has been investigated by measuring the beta decay of the low-spin isomer in Co-68 selectively produced in the decay chain of Mn-68. A revised level scheme has been built based on the clear identification of beta-gamma-E0 delayed coincidences. Transitions between the three lowest-lying 0(+) and 2(+) states are discussed on the basis of measured intensities or their upper limits for unobserved branches and state-of-the-art shell model calculations., Unión Europea. FP7, Spanish MINECO, Interuniversity Attraction Poles Programme, U.S. Department of Energy, Office of Science, Office of Nuclear Physics, Slovak grant agency VEGA, Slovak Research and Development Agency, FWO-Vlaanderen (Belgium), BOF KU Leuven, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© IOP Publishing LTD This project was supperted by the German Federal Ministry for Education and Research (BMBF), EU(EURONS), ExtreMe Matter Institute EMMI, GSI Darmstadt, FIAS Frankfurt Institute for Advanced Studies, and HIC for FAIR. Nuclear Physics in Astrophysics Conference (NPA) (6. 2013. Lisboa, Portugal)., The time-reversed reaction O-15(2p, gamma) Ne-17 has been studied by the Coulomb dissociation technique. Secondary 17Ne ion beams at 500 AMeV have been produced by fragmentation reactions of Ne-20 in a beryllium production target and dissociated on a secondary Pb target. The incoming beam and the reaction products have been identified with the kinematically complete LAND-(RB)-B-3 experimental setup at GSI. The excitation energy prior to decay has been reconstructed by using the invariant-mass method. The preliminary differential and integral Coulomb Dissociation cross sections (sigma(Coul)) have been calculated, which provide a photoabsorption (sigma(photo)) and a radiative capture cross section (sigma(cap)). Additionally, important information about the nuclear structure of the Ne-17 nucleus will be obtained. The analysis is in progress., German Federal Ministry for Education and Research (BMBF), EU(EURONS), ExtreMe Matter Institute EMMI, GSI Darmstadt, FIAS Frankfurt Institute for Advanced Studies, HIC for FAIR, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

©2016 American Physical Society. Articulo firmado por más de 10 autores. The authors wish to thank the accelerator staff of GSI for their active support during the experiment. Ushasi Datta acknowledges the Alexander von Humboldt Foundation and SEND project (PIN: 11-R&D-SIN-5.11-0400), Govt. of India, for their support of the experimental investigation and is also grateful to Prof. B. M. Sherrill, NSCL, and Prof. Larry Zamick, Rutgers University, for many valuable suggestions and discussion., The first direct experimental evidence of a multiparticle-hole ground state configuration of the neutron-rich Mg-33 isotope has been obtained via intermediate energy (400 A MeV) Coulomb dissociation measurement. The major part similar to(70 +/- 13)% of the cross section is observed to populate the excited states of Mg-32 after the Coulomb breakup of Mg-33. The shapes of the differential Coulomb dissociation cross sections in coincidence with different core excited states favor that the valence neutron occupies both the s(1/2) and p(3/2) orbitals. These experimental findings suggest a significant reduction and merging of sd-pf shell gaps at N similar to 20 and 28. The ground state configuration of Mg-33 is predominantly a combination of Mg-32(3.0,3.5MeV; 2(-), 1(-)) circle times nu(s1/2), Mg-32(2.5MeV; 2(+)) circle times nu(p3/2), and Mg-32(0; 0(+)) circle times nu(p3/2). The experimentally obtained quantitative spectroscopic information for the valence neutron occupation of the s and p orbitals, coupled with different core states, is in agreement with Monte Carlo shell model (MCSM) calculation using 3 MeV as the shell gap at N = 20., Alexander von Humboldt Foundation, SEND project, Govt. of India, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

Work supported by the Spanish Government (FPA2015-65035-P, RTC-2015-3772-1), Comunidad de Madrid (S2013/MIT-3024 TOPUS-CM) and European Regional Funds. This is a Contribution for the Moncloa Campus of International Excellence, “Grupo de Física Nuclear-UCM”, Ref. 910059. The authors acknowledge partial support by EU's H2020 under MediNet: a Networking Activity of ENSAR-2 (grant agreement 654002)., A detection system composed of a CeBr3 scintillating crystal coupled with a photomultiplier tube and connected to a digital oscilloscope was installed in the control room of a Cyberknife™ clinical accelerator during normal irradiation in order to infer the temporal characteristics of the beam and spectral characteristics of the low-intensity scattered radiation present outside the treatment room. Three batches of 20,000 pulses were measured at three different gantry angles. After digitalization and post-processing of the signals, the time profile of the beam pulses was determined with an accuracy of 14 ns with respect to the gating signal, while the energy spectrum of the measured radiation field could be acquired with a resolution of 5.5%. The proposed device makes it possible, thanks to the increased sensitivity of the scintillating crystals and the digital signal processing techniques in place, to monitor the properties of the radiation present outside the bunker produced by the treatment beam, minimizing interference with patient treatment, QA or research activitie, Unión Europea. Horizonte 2020, Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Campus de Excelencia Internacional Moncloa, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2015 Elsevier B.V. This work was partially supported by the Spanish MINECO through Projects FPA2010-17142, FPA2013-41267-P and Consolider-CPAN CSD-2007-00042. Funding by the ERA-NET NuPNET via Spanish Project PRI-PIMNUP-2011-1338 (FATIMA-NuPNET) and Bulgarian Project DNS7RP01-4 (FATIMA-NuPNET) is also recognized. V.V. and H.M. acknowledge the financial aid by the Consolider-CPAN CSD-2007-00042 project. The electronics for the test bench and the reference detectors were provided by the Fast Timing Pool of Electronics and MASTICON., We have characterized in depth the time response of three detectors equipped with cylindrical LaBr_3(Ce) crystals with dimensions of 1-in. in height and 1-in. in diameter, and having nominal Ce doping concentration of 5%, 8% and 10%. Measurements were performed at Co-60 and Na-22 gamma-ray energies against a fast BaF2 reference detector. The time resolution was optimized by the choice of the photomultiplier bias voltage and the fine tuning of the parameters of the constant fraction discriminator, namely the zero-crossing and the external delay. We report here on the optimal time resolution of the three crystals. It is observed that timing properties are influence('by the amount of Ce doping and the crystal homogeneity. For the crystal with 8% of Ce doping the use of the ORTEC 935 CFD at very shorts delays in addition to the Hamamatsu R9779 PMT has made it possible to improve the LaBr3(Ce) time resolution from the best literature value at Co-60 photon energies to below 100 ps. (C) 2015 Elsevier B.V. All rights reserved., MINECO, Spain, ERA-NET NuPNET via Spanish Project, Consolider-CPAN project, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

©IOP Publishing Ltd. Artículo escrito por más de 10 autores. Nuclear Physics in Astrophysics Conference (NPA) (6. 2013. Lisboa, Portugal). This project was supported by the HGF Young Investigators Project VH-NG-327, EMMI, H4F, HGS-HIRe, JINA, NAVI, DFG and ATHENA., The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes., HGF Young Investigators, EMMI, HGS-HIRe, H4F, JINA, NAVI, DFG, ATHENA., Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2016 The Authors. Published by Elsevier B.V. Artículo publicado por más de 10 autores. The authors thank the technical services of the ILL, LPSC and GANIL for supporting the EXILL campaign. The EXOGAM collaboration and the INFN Legnaro are acknowledged for the loan of Ge detectors. This work was supported by the Italian Istituto Nazionale di Fisica Nucleare, by the Polish National Science Centre under Contract Nos. 2014/14/M/ST2/00738 and 2013/08/M/ST2/00257, by the UK Science and Technology Facilities Council and the UK National Measurement Office. Supports from the German BMBF (contract No. 05P12RDNUP), the Spanish MINECO FPA2013-41267-P and NuPNET-FATIMA (PRI-PIMNUP-2011-1338) are also acknowledged., The gamma-ray decay of excited states of the one-valence-proton nucleus Sb-133 has been studied using cold-neutron induced fission of U-235 and Pu-241 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 mu s isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr3(Ce) scintillators, revealed 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 Sn-132 and the valence proton, using Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license., Ministerio de Economía y Competitividad (MINECO), Italian Istituto Nazionale di Fisica Nucleare, Polish National Science Centre, UK Science and Technology Facilities Council, UK National Measurement Office, German BMBF, NuPNET-FATIMA, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2016 Amer Physical Soc. Articulo firmado por más de 10 autores.(R3B Collaboration) We thank the FRS and the GSI accelerator staff for their efforts. We thank Alexandra Kelic-Heil for providing us with the ABRABLA07 code and for fruitful discussions. This work was supported by the Swedish Research Council. O.T. was supported by the Spanish Research Council under project FPA2012-32443, C.A.B. acknowledges support from the U.S. DOE Grant No. DE-FG02-08ER41533 and the U.S. NSF Grant No. 1415656. L.M.F. acknowledges support by the Spanish Research Council under project FPA2013-41267-P and M.R. was supported by GSI (F&E, DR-ZUBE), German BMBF (06DR134I and 05P09CRFN5), the Nuclear Astrophysics Virtual Institute (NAVI, HGF VH-VI-417) and the Helmholtz Association Detector Technology and Systems Platform. T.K. acknowledges support by the German BMBF No. 06DA9040I, No. 05P12RDFN8, and No. 05P15RDFN1. C.W. acknowledges funding by the UK STFC No. ST/E500651/1, while N.A. and M.F. acknowledge funding by the UK STFC No. ST/F011989/1., Background: Models describing nuclear fragmentation and fragmentation fission deliver important input for planning nuclear physics experiments and future radioactive ion beam facilities. These models are usually benchmarked against data from stable beam experiments. In the future, two-step fragmentation reactions with exotic nuclei as stepping stones are a promising tool for reaching the most neutron-rich nuclei, creating a need for models to describe also these reactions. Purpose: We want to extend the presently available data on fragmentation reactions towards the light exotic region on the nuclear chart. Furthermore, we want to improve the understanding of projectile fragmentation especially for unstable isotopes. Method: We have measured projectile fragments from (10,12-18C) and B10-15 isotopes colliding with a carbon target. These measurements were all performed within one experiment, which gives rise to a very consistent data set. We compare our data to model calculations. Results: One-proton removal cross sections with different final neutron numbers (1 pxn) for relativistic C-10,C-12-18 and B10-15 isotopes impinging on a carbon target. Comparing model calculations to the data, we find that the EPAX code is not able to describe the data satisfactorily. Using ABRABLA07 on the other hand, we find that the average excitation energy per abraded nucleon needs to be decreased from 27 MeV to 8.1 MeV. With that decrease ABRABLA07 describes the data surprisingly well. Conclusions: Extending the available data towards light unstable nuclei with a consistent set of new data has allowed a systematic investigation of the role of the excitation energy induced in projectile fragmentation. Most striking is the apparent mass dependence of the average excitation energy per abraded nucleon. Nevertheless, this parameter, which has been related to final-state interactions, requires further study., Ministerio de Economía y Competitividad (MINECO), Swedish Research Council, GSI (FE, DR-ZUBE), German BMBF, Nuclear Astrophysics Virtual Institute (NAVI), Helmholtz Association Detector Technology and Systems Platform, UK STFC, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© Iop Publishing Ltd. Articulo firmado por más de 10 autores. Nuclear Physics in Astrophysics Conference (NPA) (6 .2013. Lisboa, Portugal). This work was supported by the Spanish Ministerio de Economía y Competitividad under Grants CONSOLIDER-Ingenio 2010 CSD2008-0037 (CUP), PRI-PIMNUP-2011-1348, FPA2011-28770-C03-03, FPA2011-24553, FPA2010-17142 and CSD-2007-00042 (CPAN)., The reactions C-13(alpha,n)O-16 and Ne-22(alpha,n)Mg-25 are the primary sources of neutrons for the astrophysical s-process. The feasibility of cross section measurements within the respective Gamow windows is discussed in quantitative terms for a 4 pi neutron counter, based on He-3 tubes and a neutron moderator, placed in an underground lab., Ministerio de Economía y Competitividad, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2016 Amer Physical Soc. We express our deep appreciation to the late Professor Henryk Mach, who was the initiator of this investigation. He was an inspiring collaborator, mentor, and leader in developing the beta gamma gamma (t) fast-timing technique. His memory and accomplishments will always be with us. This work was partially supported by the Spanish MINECO through Projects No. FPA2012-32443, No. FPA2013-41267-P, and CPAN Consolider (Project No. CSD-2007-00042), and by Romanian IFA Grant CERN/ISOLDE. It was also partly funded by the NuPNET network FATIMA (PRI-PIMNUP-2011-1338), by FWO-Vlaanderen (Belgium), by GOA/2010/010 (BOF KU Leuven), and by the Interuniversity Attraction Poles Programme initiated by the Belgian Science PolicyOffice (BriX network P7/12). Support from Grupo de Fisica Nuclear (GFN-UCM), Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale (PRIN) Grant No. 2001024324 01302, German BMBF under Contracts No. 05P12PKFNE and No. 05P15PKCIA, the U.K. Science and Technology Facilities Council, and the European Union Seventh Framework through ENSAR (Contract No. 262010) is also acknowledged. Fast-timing electronics were provided by the Fast Timing Collaboration, the ISOLDE Decay Station collaboration, and MASTICON., The levels in Sn-129 populated from the beta(-) decay of In-129 isomers were investigated at the ISOLDE facility of CERN using the newly commissioned ISOLDE Decay Station (IDS). The lowest 1/2(+) state and the 3/2(+) ground state in 129Sn are expected to have configurations dominated by the neutron s(1/2) (l = 0) and d(3/2) (l = 2) single-particle states, respectively. Consequently, these states should be connected by a somewhat slow l-forbidden M1 transition. Using fast-timing spectroscopy we havemeasured the half-life of the 1/2(+) 315.3-keV state, T-1/2 = 19(10) ps, which corresponds to a moderately fast M1 transition. Shell-model calculations using the CD-Bonn effective interaction, with standard effective charges and g factors, predict a 4-ns half-life for this level. We can reconcile the shell-model calculations to the measured T-1/2 value by the renormalization of the M1 effective operator for neutron holes., Spanish MINECO, CPAN Consolider, Romanian IFA Grant CERN/ISOLDE, NuPNET network FATIMA, FWO-Vlaanderen (Belgium), BOF KU Leuven, Grupo de Fisica Nuclear (GFN-UCM), Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale (PRIN), German BMBF, U.K. Science and Technology Facilities Council, European Union Seventh Framework, Interuniversity Attraction Poles Programme, Belgian Science PolicyOffice (BriX network), Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© Amer Physical Soc 2015. Artículo firmado por 12 autores. This work has been supported by the Spanish Ministerio de Ciencia e Innovacion y Ministerio de Economia y Competitividad through projects no. FPA2008-06419-C02-01, FPA2011-24553, FPA2013-41267-P, FPA2014-52823-C2-1-P, FRPA2012-32443, FIS2011-23565, and CSD-2007-00042 (CPAN Consolider, Ingenio2010), by the European Union Seventh Framework via ENSAR (contract no. 262010), contract no. PIOF-GA-2011-298364 and by OTKA contracts no. K100835 and K106035. Some of the Spanish projects are co-financed by FEDER funds., The beta decay of Pb-192,Pb-190 has been studied using the total absorption technique at the ISOLDE (CERN) facility. The beta-decay strength deduced from the measurements, combined with QRPA theoretical calculations, allow us to infer that the ground states of the Pb-192,Pb-190 isotopes are spherical. These results represent the first application of the shape determination method using the total absorption technique for heavy nuclei and in a region where there is considerable interest in nuclear shapes and shape effects., Unión Europea. FP7, Ministerio de Ciencia e Innovacion (MICINN), Ministerio de Economia y Competitividad (MINECO), OTKA, FEDER funds, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

Current experimental nuclear physics requires the continuous development of new detection and analysis systems, whose characteristics and properties surpass those already existing. These systems are not only useful in experimental nuclear physics, but they are of interest in any field where nuclear radiation detector is required, such as nuclear medicine and radiotherapy, where imaging and monitoring techniques are in continuous evolution and development. The main goal of this thesis is to explore electronics for data acquisition (DAQ) to be used in these experiments, taken from the digital domain. Indeed, we study techniques based on the digitization of the signal from the different detectors analyzed in this work. The main advantage of digitizing these signals is that by doing so, we have a complete control over the processing and analysis of the signal, without the need for specific analog electronics. In this thesis, the digitization of signals has been covered from two different angles: 1. Digitizing the detector signals with high precision, using a high speed digitizer with a sampling speed fulfilling the Nyquist criteria and thus recording the full bandwidth of the signal, into a large number of bits (>12 bits) of resolution for the sampled signals. By doing this we obtain a signal which contains all the information in the original analog pulses. Once the data are digitized, highly complex processing algorithms can be tested that are difficult to reproduce with conventional analog electronics. With this methodology, we show that, using a sufficiently powerful digitizer and processing algorithms, the state of the art results based in the conventional analysis of analog pulse shaping can be easily matched or even surpassed. 2. The other division of DAQ focuses towards inexpensive, very compact, very versatile digital oscilloscopes. We have designed digital DAQ (DDAQ) where we have shown that with the right signal processing algorithms, even with less resolution

Proyecto de innovación docente con el objetivo de desarrollar una herramienta que facilite el aprendizaje de las aplicaciones a la Medicina de la Física Nuclear. Se ha creado el sitio web https://fisnucmed.wordpress.com/. Se abordan, entre otros contenidos, las radiaciones ionizantes y los fundamentos de la interacción de la radiación con la materia, nociones de detección de radiación e instrumentación nuclear , diagnóstico por imagen, y las modalidades de imagen PET, SPECT, CT, resonancia magnética nuclear, ultrasonidos, así como la radioterapia y en particular la hadronterapia.

The evolution of the nuclear shell structure for nuclei with large neutron to proton ratios is an open problem in contemporary nuclear physics research. The study of the regions around exotic doubly-magic nuclei plays an important role in the understanding of how shell structure evolves, and provides key input for theoretical calculations, which can be then used over larger areas of the nuclear chart. The present PhD work is focused on the study of the nuclear structure in the region around 132Sn (Z=50 and N=82), the heaviest doubly-magic nucleus away from stability within reach at current experimental facilities. The nucleus 132Sn itself is of importance for the description of the exotic nuclear region around N = 82 and to provide insight into particle-hole couplings for both protons and neutrons. The nuclei with a valence particle or hole around 132Sn are relevant for investigating the single-particle states in the region, and the matrix elements of the electromagnetic transitions interconnecting them..., La evolución de la estructura de capas en núcleos exóticos con exceso de neutrones es un tema de investigación de actualidad en física nuclear. El estudio de núcleos situados en las regiones alrededor de los núcleos doblemente mágicos resulta de vital importancia para comprender la evolución de la estructura de capas a medida que nos alejamos del valle de estabilidad. Es además importante para poder realizar cálculos teóricos que puedan extenderse a regiones amplias e inexploradas de la tabla de núcleos. Esta tesis doctoral se centra en el estudio de la región alrededor de 132Sn (Z=50 yN=82), el núcleo exótico doblemente mágico más pesado al alcance de las instalaciones experimentales actuales...

Current experimental nuclear physics requires the continuous development of new detection and analysis systems, whose characteristics and properties surpass those already existing. These systems are not only useful in experimental nuclear physics, but they are of interest in any field where nuclear radiation detector is required, such as nuclear medicine and radiotherapy, where imaging and monitoring techniques are in continuous evolution and development. The main goal of this thesis is to explore electronics for data acquisition (DAQ) to be used in these experiments, taken from the digital domain. Indeed, we study techniques based on the digitization of the signal from the different detectors analyzed in this work. The main advantage of digitizing these signals is that by doing so, we have a complete control over the processing and analysis of the signal, without the need for specific analog electronics. In this thesis, the digitization of signals has been covered from two different angles: 1. Digitizing the detector signals with high precision, using a high speed digitizer with a sampling speed fulfilling the Nyquist criteria and thus recording the full bandwidth of the signal, into a large number of bits (>12 bits) of resolution for the sampled signals. By doing this we obtain a signal which contains all the information in the original analog pulses. Once the data are digitized, highly complex processing algorithms can be tested that are difficult to reproduce with conventional analog electronics. With this methodology, we show that, using a sufficiently powerful digitizer and processing algorithms, the state of the art results based in the conventional analysis of analog pulse shaping can be easily matched or even surpassed. 2. The other division of DAQ focuses towards inexpensive, very compact, very versatile digital oscilloscopes. We have designed digital DAQ (DDAQ) where we have shown that with the right signal processing algorithms, even with less resolution, En la actualidad, en física nuclear experimental es de gran importancia el desarrollo continuo de nuevos sistemas de detección y análisis, cuyas características y propiedades superen a los ya existentes. La aplicación de estos sistemas no se restringe a la física experimental, sino que pueden ser aplicados en cualquier ámbito en que sea necesario medir radiación nuclear, como en medicina nuclear y radioterapia, donde las técnicas de imagen y monitorización, que están en continua evolución y desarrollo, precisan de unos sistemas de detección cada vez más precisos y económicos. El objetivo principal de esta tesis radica en la exploración de alternativas puramente digitales para la electrónica de adquisición (DAQ). Para ello hemos trabajado con técnicas basadas en la digitalización de la señal proporcionada por los distintos detectores analizados en este trabajo. La principal ventaja de digitalizar estas señales es que nos proporciona un control completo sobre el procesado y análisis de la misma, con gran versatilidad, sin necesidad de una electrónica específica para cada necesidad y que puede ser mucho más compleja. En el trabajo realizado en esta tesis, la digitalización de las señales se ha estudiado en dos vertientes distintas: • Digitalizando las señales del detector con una alta precisión, es decir, un muestreo que cumple el criterio de Nyquist para representar todas las frecuencias de la señal, y con alta resolución (> 12 bits) en la discretización de los valores de las muestras. Haciendo esto obtenemos una réplica digital de la señal analógica sin perder ni un ápice de información: Sobre los datos digitalizados se pueden probar formas de procesado de una alta complejidad que difícilmente son reproducibles con electrónica analógica convencional. Con esta metodología, demostráremos que con un digitalizador suficientemente potente, el estado del arte del análisis analógico de pulsos puede ser fácilmente igualado o incluso superado por el procesamiento digital. • E

In this paper, the technicalities performed to obtain a pulsed beam at the CMAM facility will be explained. The pulsed beam has been characterized with an 8 MeV proton beam, using an existing equipment at CMAM: two pairs of electrostatic plates (RASTER) that deflect the beam, commonly used for homogeneous irradiation of large areas. A pulsed beam is used in many areas such as nuclear physics, material science and, in particular, for proton-therapy medical studies. Rectangular and pyramidal functions have been used to generate different pulses and characterize the response of the RASTER. The results point out that the pulses obtained are suitable for preclinical proton-therapy studies in the FLASH regime, which consists on fractionating the dose in time with short and intense pulses. The set-up for the characterization has been a function generator and a Si-PM outside the chamber.

The evolution of the nuclear shell structure for nuclei with large neutron to proton ratios is an open problem in contemporary nuclear physics research. The study of the regions around exotic doubly-magic nuclei plays an important role in the understanding of how shell structure evolves, and provides key input for theoretical calculations, which can be then used over larger areas of the nuclear chart. The present PhD work is focused on the study of the nuclear structure in the region around 132Sn (Z=50 and N=82), the heaviest doubly-magic nucleus away from stability within reach at current experimental facilities. The nucleus 132Sn itself is of importance for the description of the exotic nuclear region around N = 82 and to provide insight into particle-hole couplings for both protons and neutrons. The nuclei with a valence particle or hole around 132Sn are relevant for investigating the single-particle states in the region, and the matrix elements of the electromagnetic transitions interconnecting them...

The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the spin-orbit shell gap towards the neutron dripline. To do so, we employed (p,2p) quasi-free scattering reactions to measure the proton component of the state of 16,18,20C. The experimental findings support the notion of a moderate reduction of the proton spin-orbit splitting, at variance to recent claims for a prevalent magic number towards the neutron dripline.

Nuclei with few valence particles outside of a doubly-magic core provide valuable information about single-particle energies, nucleon-nucleon e_ective interactions and may give insight into the onset of collectivity. The region around 132Sn draws particular attention because of the unexpected modi_cations of the shell structure and the sudden collective behaviour that arises. The 136Te nucleus, with two protons and two neutrons coupled to the doubly-magic 132Sn (Z=50 and N=82) constitutes an excellent testing ground for the study of these phenomena, and so it is studied in this PhD thesis. One of the best means to study exotic nuclei is through lifetime measurements of excited states since they allow direct and model independent access to electromagnetic transition probabilities, which are key quantities for the study of single-particle configurations, nuclear collectivity, and make it possible to test theoretical models. Thus this PhD thesis investigates the 136Te nucleus through the lifetime measurements of its excited states..., El estudio de núcleos con unos pocos nucleones de valencia fuera de la estructura de un núcleo doblemente mágico proporciona información muy relevante sobre los estados de partícula independiente, sobre las interacciones entre nucleones, y puede ayudar a comprender el comportamiento colectivo. Debido a las modificaciones que aparecen en la estructura de capas y los comportamientos colectivos observados en la región cercana al doblemente mágico 132Sn, el núcleo 136Te atrae gran interés, siendo un caso representativo para el estudio de estos fenómenos, ya que cuenta con dos protones y dos neutrones acoplados al 132Sn (Z=50 and N=82), por ende es estudiado en esta tesis. Una de las mejores maneras para estudiar estas características es la medida de las vidas medias de estados nucleares excitados, ya que permiten el acceso directo a las probabilidades de transición electromagnética, que son magnitudes clave en la física nuclear. Las probabilidades reducidas de transición son especialmente adecuadas para obtener información sobre configuraciones de partícula independiente, sobre efectos colectivos y configuraciones deformadas, además de permitir poner a prueba los modelos teóricos. Los tiempos de vida de estados excitados son observables directos que pueden ser medidos con buena precisión, lo que nos permite obtener probabilidades de transición independientes de modelo...

El teneso ocupa el penúltimo lugar del séptimo período de la tabla periódica.

The quasi-free scattering reactions 11C(p, 2p) and 10,11,12C(p, pn) have been studied in inverse kinematics at beam energies of 300–400 MeV/u at the R3B-LAND setup. The outgoing proton-proton and protonneutron pairs were detected in coincidence with the reaction fragments in kinematically complete measurements. The efficiency to detect these pairs has been obtained from GEANT4 simulations which were tested using the 12C(p, 2p) and 12C(p, pn) reactions. Experimental cross sections and momentum distributions have been obtained and compared to DWIA calculations based on eikonal theory. The new results reported here are combined with previously published cross sections for quasi-free scattering from oxygen and nitrogen isotopes and together they enable a systematic study of the reduction of singleparticle strength compared to predictions of the shell model over a wide neutron-to-proton asymmetry range. The combined reduction factors show a weak or no dependence on isospin asymmetry, in contrast to the strong dependency reported in nucleon-removal reactions induced by nuclear targets at lower energies. However, the reduction factors for (p, 2p) are found to be ’significantly smaller than for (p, pn) reactions for all investigated nuclei.