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Neutron capture cross section measurements in time-of-flight facilities are usually performed by detecting the prompt γ-rays emitted in the capture reactions. One of the difficulties to be addressed in these measurements is that the emitted γ-rays may change with the neutron energy, and therefore also the detection efficiency. To deal with this situation, many measurements use the so called Total Energy Detection (TED) technique, usually in combination with the Pulse Height Weighting Technique (PHWT). With it, it is sought that the detection efficiency depends only on the total energy of the γ-ray cascade, which does not vary much with the neutron energy. This technique was developed in the 1960s and has been used in many neutron capture experiments to date. One of the requirements of the technique is that γ-ray detectors have a low efficiency. This has meant that the PHWT has been used with experimental setups with low detection efficiencies. However, this condition does not have to be fulfilled by the experimental system as a whole. The main goal of this work is to show that it is possible to measure with a high efficiency detection system that uses the PHWT, and how to analyze the measured data., This work was supported in part by the I+D+i grant PGC2018- 096717-B-C21 funded by MCIN/AEI/10.13039/501100011033 and by the European Commission H2020 Framework Programme project SANDA (Grant agreement ID: 847552).

International audience; Background: The N14(n,p)C14 reaction is of interest in neutron capture therapy, where nitrogen-related dose is the main component due to low-energy neutrons, and in astrophysics, where N14 acts as a neutron poison in the s process. Several discrepancies remain between the existing data obtained in partial energy ranges: thermal energy, keV region, and resonance region.Purpose: We aim to measure the N14(n,p)C14 cross section from thermal to the resonance region in a single measurement for the first time, including characterization of the first resonances, and provide calculations of Maxwellian averaged cross sections (MACS).Method: We apply the time-of-flight technique at Experimental Area 2 (EAR-2) of the neutron time-of-flight (n_TOF) facility at CERN. B10(n,α)Li7 and U235(n,f) reactions are used as references. Two detection systems are run simultaneously, one on beam and another off beam. Resonances are described with the R-matrix code sammy.Results: The cross section was measured from subthermal energy to 800 keV, resolving the first two resonances (at 492.7 and 644 keV). A thermal cross section was obtained (1.809±0.045 b) that is lower than the two most recent measurements by slightly more than one standard deviation, but in line with the ENDF/B-VIII.0 and JEFF-3.3 evaluations. A 1/v energy dependence of the cross section was confirmed up to tens of keV neutron energy. The low energy tail of the first resonance at 492.7 keV is lower than suggested by evaluated values, while the overall resonance strength agrees with evaluations.Conclusions: Our measurement has allowed determination of the N14(n,p) cross section over a wide energy range for the first time. We have obtained cross sections with high accuracy (2.5%) from subthermal energy to 800 keV and used these data to calculate the MACS for kT=5 to kT=100 keV.

19 pags., 14 figs., 3 tabs., A γ-ray spectroscopic study of Po212 was performed at the Grand Accélérateur National d'Ions Lourds, using the inverse kinematics α-transfer reaction C12(Pb208,Po212)Be8 and the AGATA spectrometer. A careful analysis based on γγ coincidence relations allowed us to establish 14 new excited states in the energy range between 1.9 and 3.3 MeV. None of these states, however, can be considered as candidates for the levels with spins and parities of 1- and 2- and excitation energies below 2.1 MeV, which have been predicted by recent α-cluster model calculations. A systematic comparison of the experimentally established excitation scheme of Po212 with shell-model calculations was performed. This comparison suggests that the six states with excitation energies (spins and parities) of 1744 (4-), 1751 (8-), 1787 (6-), 1946 (4-), 1986 (8-), and 2016 (6-) keV, which previously were interpreted as α-cluster states, may in fact be of positive parity and belong to low-lying shell-model multiplets. This reinterpretation of the structure of Po212 is supported by experimental information with respect to the linear polarization of γ rays, which suggests a magnetic character of the 432-keV γ ray decaying from the state at an excitation energy of 1787 keV to the 61+ yrast state, and exclusive reaction cross sections., This project has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 654002 and FEDER funds. We furthermore acknowledge support from the Spanish Ministerio de Ciencia, Inovación y Universidades under contracts FPA2014-57196-C5, FPA2017-84756-C4, and SEV-2014-0398, the Generalitat Valenciana under Grant No. PROMETEO/2019/005, the Swedish Research Council (Vetenskapsrådet, VR 2016-3969), and the German BMBF under Contracts No. 05P18PKFN9 and No. 05P19PKFNA.

5 pags., 4 figs., The low-lying excited states in the neutron-deficient N=Z+1 nucleus Tc444387 have been studied via the fusion-evaporation reaction Fe54(Ar36, 2n1p)Tc87 at the Grand Accélérateur National d'Ions Lourds (GANIL), France. The AGATA spectrometer was used in conjunction with the auxiliary NEDA, Neutron Wall, and DIAMANT detector arrays to measure coincident prompt γ rays, neutrons, and charged particles emitted in the reaction. A level scheme of Tc87 from the (9/2g.s.+) state to the (33/21+) state was established based on six mutually coincident γ-ray transitions. The constructed level structure exhibits a rotational behavior with a sharp backbending at ω≈0.50 MeV. A decrease in alignment frequency and increase in alignment sharpness in the odd-mass isotonic chains around N=44 is proposed as an effect of the enhanced isoscalar neutron-proton interactions in odd-mass nuclei when approaching the N=Z line., This work was supported by the Swedish Research Council under Grants No. 621-2014-5558 and No. 2019-04880, the EU 7th Framework Programme, Integrating Activities Transnational Access, Project No. 262010 ENSAR, the UK STFC under Grants No. ST/L005727/1 and No. ST/P003885/1, the Polish National Science Centre, Grants No. 2017/25/B/ST2/01569, No. COPIN-INFN, No. COPIN-IN2P3, and No. COPIGAL projects, the National Research, Development and Innovation Fund of Hungary (Project No. K128947), the European Regional Development Fund (Contract No. GINOP-2.3.3-15-2016-00034), the Hungarian National Research, Development and Innovation Office - NKFIH, Contract No. PD124717, the Ministerio de Ciencia e Innovación and Generalitat Valenciana, Spanish, under Grants No. SEV-2014-0398, No. FPA2017-84756-C4, and No. PROMETEO/2019/005 and by the EU FEDER funds. X.L. gratefully acknowledges support from the China Scholarship Council, Grant No. 201700260183 for his stay in Sweden.

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable Tm171 (t1/2=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of Tm171 at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the Yb171 abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation. Ministerio de Economía y Competitividad FPA2013-45083-P, FPA2014-53290-C2-2-P, FPA2016-77689-C2-1-R European Community 334315, 605203 Israel Science Foundation 1387/15 Science and Technology Facilities Council UK ST/M006085/1 European Research Council ERC-2015-STG-677497

A new method for measuring \ngr cross sections aiming at enhanced signal-to-background ratio is presented. This new approach is based on the combination of the pulse-height weighting technique with a total energy detection system that features $\gamma$-ray imaging capability (i-TED). The latter allows one to exploit Compton imaging techniques to discriminate between true capture $\gamma$-rays arising from the sample under study and background $\gamma$-rays coming from contaminant neutron (prompt or delayed) captures in the surrounding environment. A general proof-of-concept detection system for this application is presented in this article together with a description of the imaging method and a conceptual demonstration based on Monte Carlo simulations., Comment: Article submitted to Nucl. Instr. and Meth. in Phys. Res. A

The elements heavier than iron are produced in the Universe mainly by means of the slow (s) and rapid (r) neutron capture processes (for a recent review see e.g. [1]). The latter nucleosynthesis mechanism occurs between the valley of stability and the neutron drip line, passing along the neutron shell closures where exceptionally long half-lives and small neutron capture cross sections yield the three characteristic abundance maxima at A ~ 80, 130 and 195.

10 pages, 6 figures.-- PACS nrs.: 25.40.Lw; 27.80.+w; 97.10.Cv.-- ISI Article Identifier: 000250620900078.-- ArXiv pre-print available at: http://arxiv.org/abs/0707.3679, The (n,γ) cross section of Pb-206 has been measured at the CERN n_TOF facility with high resolution in the energy range from 1 eV to 620 keV by using two optimized C6D6 detectors. In the investigated energy interval about 130 resonances could be observed, from which 61 had enough statistics to be reliably analyzed via the R-matrix analysis code SAMMY. Experimental uncertainties were minimized, in particular with respect to (i) angular distribution effects of the prompt capture γ-rays, and to (ii) the TOF-dependent background due to sample-scattered neutrons. Other background components were addressed by background measurements with an enriched Pb-208 sample. The effect of the lower energy cutoff in the pulse height spectra of the C6D6 detectors was carefully corrected via Monte Carlo simulations. Compared to previous Pb-206 values, the Maxwellian averaged capture cross sections derived from these data are about 20% and 9% lower at thermal energies of 5 keV and 30 keV, respectively. These new results have a direct impact on the s-process abundance of Pb-206, which represents an important test for the interpretation of the cosmic clock based on the decay of U-238.

9 pages, 3 figures.-- PACS nrs.: 25.40.Lw; 27.80.+w; 97.10.Cv.-- ISI Article Identifier: 000243896000061.-- ArXiv pre-print available at: http://arxiv.org/abs/nucl-ex/0610033, The neutron capture cross section of Pb-204 has been measured at the CERN n_TOF installation with high resolution in the energy range from 1 eV to 440 keV. An R-matrix analysis of the resolved resonance region, between 1 eV and 100 keV, was carried out using the SAMMY code. In the interval between 100 keV and 440 keV we report the average capture cross section. The background in the entire neutron energy range was reliably determined from the measurement of a Pb-208 sample. Other systematic effects in this measurement were investigated and precisely corrected by means of detailed Monte Carlo simulations. We obtain a Maxwellian average capture cross section for Pb-204 at kT=30 keV of 79(3) mb, in agreement with previous experiments. However our cross section at kT=5 keV is about 35% larger than the values reported so far. The implications of the new cross section for the s-process abundance contributions in the Pb/Bi region are discussed., This work was supported by the European Commission (FIKW-CT-2000-00107), by the Spanish Ministry of Science and Technology (FPA2001-0144-C05), and partly by the Italian MIUR-FIRB grant "The astrophysical origin of the heavy elements beyond Fe".

Neutron capture cross sections are fundamental in the study of the slow neutron capture process of nucleosynthesis, also known as the s-process, which produces half of the observed solar system abundances of elements heavier than iron. Some nuclei along the nucleosynthesis chain are unstable, and there the capture process competes with the decay process, creating a split in the nucleosynthesis path. The nuclear properties of some of these radionuclides change with the conditions of the stellar environment, a fact that influences the local abundance pattern. 204Tl is a very interesting branching point, because it is shielded from any contribution from other nucleosynthesis processes. The result is that both 204Tl and its stable daughter isotope 204Pb are only produced by the s-process. Hence, by competing with the beta decay, the capture cross section of 204Tl crucially determines the final abundance of 204Pb. A faithful prediction of the solar abundances of s-only isotopes, like 204Pb, is one of the key accuracy tests for modern stellar nucleosynthesis calculations. However, until the present work, due to the challenges of performing a capture measurement on 204Tl, there was no experimental data of its cross section. Thus, large uncertainties existed in its capture cross section, which hampered a more accurate and precise knowledge of the predicted s-process production of 204Pb. By affecting the abundance of 204Pb, the cross section of 204Tl(n,¿) also influences the ratio of abundances 205Pb/204Pb. 205Pb is also produced only by the s-process, and it is radioactive, with a long half-life of 17.2 My. Therefore, the ratio of abundances of 205Pb/204Pb has the potential to be used as a chronometer of the s-process. In the year 2013, a sample enriched up to a few percent in 204Tl was produced by neutron irradiation of a 203Tl seed sample at the high thermal neutron flux nuclear reactor of the ILL, in Grenoble (France). Two years later, the 204Tl enriched sample was employed to measure, for the first time, the capture cross section of 204Tl at the n TOF time-of-flight facility at CERN. The measurement was possible thanks to the unique features of this facility, in particular, its high instant neutron flux low background levels. The measurement was performed employing the well-established total energy detection technique (TED), which offers a very low neutron sensibility, and low levels of background, compared to other methods like the Total Absorption technique. The main challenges for the 204Tl measurement were the very high background due to the activity of the sample, the very low amount of material, and the limited knowledge of the geometry of the sample. Such difficulties required the adoption of specific solutions during the measurement and the posterior data analysis. Related to this, several sources of systematic error were evaluated by means of Monte Carlo simulations. The complications with the 204Tl sample geometry required to apply an in-sample normalization procedure. For this purpose, an ancillary capture measurement on a 203Tl sample was also performed in the same experimental campaign. As a stable nuclide, most of the sources of systematic error could be kept under control. This allowed for an accurate R-matrix analysis of the most relevant capture levels in the resolved resonance region of 203Tl, including the first ever measurement under 3 keV of neutron energy. As a result, the present work has contributed, as well, to improve the 203Tl stellar capture cross section in the 8 to 25 keV neutron energy range. With the improved 203Tl(n,gamma) cross section, an R-matrix analysis of several 204Tl resonances was made possible. These results were employed to experimentally constrain the 204Tl stellar cross section at low energies, and setting additional limits to the stellar cross section predicted by nuclear data evaluations at s-process temperatures. Les seccions eficaces de captura de neutrons són fonamentals en l'estudi del procés lent de nucleosíntesi estel·lar dels elements, també conegut com a procés s (de l'anglès "slow"). El procés s és responsable de la producció d'aproximadament la meitat de les abundàncies solars dels elements més pesats que el ferro. Alguns nuclis en la cadena de nucleosíntesi són inestables, i en aquests el procés de captura competeix amb el procés de desintegració, el que dóna lloc a una ramificació del camí de producció dels elements. Les propietats nuclears d'alguns d'aquests núclids canvien amb les condicions de l'entorn estel·lar on són produïts, el que influencia el patró d'abundàncies local. El 204Tl és un punt de ramificació molt interessant, perquè està protegit de contribucions d'altres processos de nucleosíntesi. El resultat és que tant el 204Tl com el seu producte de desintegració 204Pb només són produïts pel procés s. Per tant, degut que competeix amb el procés de desintegració, la secció eficaç de captura neutrònica del 204Tl és clau per fixar l'abundància final de 204Pb. Una predicció cartera de l'abundància dels núclids només produïts pel procés s és una de les proves de precisió dels models de càlculs de nucleosíntesi estel·lar. Tot i això, fins el present treball, no hi havia dades de la seva secció eficaç degut al reptes en la realització d'una mesura de captura en el 204Tl. Això feia que hi hagués una incertesa important en la secció eficaç estel·lar, la qual cosa dificultava una predicció precisa de la producció de 204Pb pel procés s. De la mateixa manera, la secció eficaç de 204Tl(n,y) també afecta la relació d'abundàncies 205Pb/204Pb. Degut al fet que el 205Pb és radioactiu, amb un període de semidesintegració de 17,2 Ma, la dita relació té el potencial de ser usada com a cronòmetre del procés s. L'any 2013, es va produir una mostra enriquida en 204Tl per irradiació neutrònica d'una llavor de 203Tl al reactor nuclear del ILL de Grenoble (França). Dos anys després, la mostra enriquida es va fer servir per mesurar, per primera vegada, la secció eficaç de captura del 204Tl utilitzant la tècnica de temps de vol a l'experiment n_TOF del CERN. La mesura va ser possible gràcies a les característiques úniques d'aquesta instal·lació, en particular, l'elevat flux instantani de neutrons i els nivells baixos de fons. La mesura es va dur a terme mitjançant la tècnica de Detecció Total d'Energia (TED, en anglès), que té com a avantatges una sensibilitat de detecció de neutrons molt baixa, i una baixa taxa de detecció de fons. Els principals reptes en la mesura de 204Tl(n,y) van ser la gran quantitat de senyals de fons causats per l'activitat de la mostra, la baixa quantitat de material disponible, i el coneixement limitat de la geometria de la mostra després del procés d'irradiació. Totes aquestes dificultats han requerit l'adopció de solucions específiques durant la mesura i l'anàlisi de dades posterior. Les complicacions amb la geometria de la mostra van fer necessari aplicar un mètode d'autonormalització. Per aquest propòsit es va dur a terme una mesura auxiliar de captura en 203Tl durant la mateixa campanya experimental. Com que el 203Tl es estable, els principals errors sistemàtics de mesura es van poder mantenir baixos. Això ha permès fer un anàlisi de tipus R-matrix de les principals ressonàncies de captura neutrònica del 203Tl, incloent la primera mesura dels nivells per sota de 3 keV. Això ha contribuït a millorar la secció eficaç de captura estel·lar del 203Tl en el rang entre 8 keV i 25 keV d'energia tèrmica dels neutrons. La secció eficaç millorada de la reacció 203Tl(n,y) ha permès realitzar un anàlisi de diverses ressonàncies de captura del 204Tl. Els resultats s¿han utilitzat per fitar la secció eficaç estel·lar del 204Tl a energies de neutrons baixes, i així limitar els valors possibles a la secció transversal estel·lar predits per les avaluacions de dades nuclears a temperatures del procés s.

El trabajo desarrollado en esta Tesis se centra en estudio experimental del comportamiento colectivo de los estados excitados de los núcleos semimágicos con N=50 en función de la ocupación del orbital g9/2 de protones, a través de la medida de la vida media de los estados "yrast" 4+ de los núcleos 92Mo y 94Ru. En particular, se ha investigado la conservación de "seniority" a lo largo de la capa g9/2 que es la primera capa donde podría no conservarse. El 100Sn, siendo el núcleo doblemente mágico ligado más pesado con igual número de protones y neutrones, ha atraído siempre un considerable interés desde el punto de vista experimental y teórico. La estructura de este núcleo y sus vecinos son excelentes referencias para probar los cálculos de modelos de capas de última generación en esta región emblemática de la tabla nuclear. Además, el estudio de las propiedades de la capa g9/2 a través de los isótopos con N=50 en las proximidades del 100Sn es de gran interés para entender las diferencias y similitudes con respecto a los isótopos con Z=28 hacia el 78Ni puesto que tienen los mismos nucleones de valencia para protones y neutrones, respectivamente. Esta situación se denomina "valence mirror symmetry". En este contexto, los modelos de capas predicen la conservación de "seniority" hacia la ocupación completa del orbital g9/2 en el primer caso debido a una fuerza de "pairing" creciente a lo largo de los isótonos con N=50, contrariamente a lo que sugieren para el segundo caso. Para probar este fenómeno, las probabilidades de transición reducida de las transiciones "yrast" 4+->2+ en los núcleos 92Mo y 94Ru, han sido determinadas experimentalmente por primera vez a través de medidas de vida media en el laboratorio de GANIL (Caen, Francia). El mecanismo de reacción usado para poblar los núcleos de interés, ricos en protones, fue la reacción de transferencia de varios nucleones raramente usada para poblar dichos núcleos. En este experimento, un haz de 92Mo con una energía de 716.9 MeV incidió en un blanco de 92Mo del IKP Plunger, mientras que una lámina de 24Mg se usó para degradar la energía de los productos de reacción con la finalidad de medir la vida media de los estados excitados con la técnica RDDS. Los productos de reacción de interés se identificaron con el espectrómetro magnético VAMOS++ y los rayos gamma en coincidencia con los productos de reacción identificados se midieron usando AGATA. A través de este experimento se ha podido determinar las probabilidades de transición reducida de las transiciones "yrast" 4+->2+ y 2+->0+ en los núcleos 92Mo y 94Ru y las transiciones "yrast" 4+->2+ y 6+->4+ en los núcleo 90Zr (también útil para completar la sistemática de los núcleos con N=50), permitiendo un estudio completo del esquema de "seniority" en el orbital g9/2 para protones. Estos resultados obtenidos para las probabilidades de transición reducida en los núcleos 92Mo y 94Ru (y 90Zr, por completitud) han sido interpretados en base a las predicciones del modelo de capas usando una interacción realista en el espacio de valencia de protones f5/2, p3/2, p1/2, g9/2. Esta interpretación ha permitido también la comparación del comportamiento de la estructura nuclear entre los núcleos con "valence mirror symmetry". Adicionalmente, parte de esta Tesis ha sido dedicada al estudio del rendimiento del detector espectroscopia gamma de última generación y alta resolución usado en este experimento. AGATA (Advanced Gamma Tracking Array) es un multi-detector compuesto por cristales de germanio de alta pureza, con contactos eléctricamente segmentados, sensibles a la posición y con capacidad de trazar la absorción del fotón gamma dentro del detector. AGATA es el resultado de varios avances técnicos con el fin de identificar la posición de interacción y obtener una alta sensibilidad (eficiencia, "peak-to-total" y corrección Doppler) en condiciones de medida difíciles (elevada tasa de conteo y alta tasa de fondo), como sucede en la segunda generación de instalaciones de haces radiactivos. La caracterización de AGATA realizada en esta Tesis evalúa los datos medidos con fuentes radiactivas y datos medidos con el haz de 92Mo con 23 cristales de germanio. The present Thesis describes my experimental studies on the evolution of collectivity of the nuclear excited states in the vicinity of the doubly-magic nucleus 100Sn via lifetime measurements of the yrast states in 92Mo and 94Ru. In particular, the conservation of seniority along the g9/2 shell has been investigated. This shell is the first one in which the seniority might not be conserved. Excellent cases for studying the properties of this shell are the N=50 isotones in the vicinity of 100Sn and the Z=28 isotopes towards 78Ni, which have the same valence nucleons for protons and neutrons, respectively (this situation is named valence-mirror symmetry). In the former case, shell model calculations predict the conservation of seniority towards the complete occupation of the g9/2 orbital due to an increasing pairing-strength along the N=50 isotones, which differs from what the calculations suggest for the latter case. To test this phenomenon, the reduced transition probabilities for the 4+->2+ yrast transitions, in 92Mo and 94Ru nuclei, have been determined experimentally for the first time via lifetime measurements at the GANIL laboratory (Caen, France). The multi-nucleon transfer reaction mechanism was unconventionally used to populate the proton-rich nuclei of interest. In this experiment, a 92Mo beam with an energy of 716.9 MeV impinged on the stretched 92Mo target of the IKP Cologne plunger, while a 24Mg foil was used to degrade the energy of the reaction products to measure the lifetime with the RDDS technique. The reaction products of interest have been identified with the magnetic spectrometer VAMOS++, while the gamma-rays in coincidence with the identified reaction products have been measured using AGATA. From this experiment the reduced transition probabilities for the 4+->2+ and 2+->0+ yrast transitions in 92Mo and 94Ru and for the 4+->2+ and 6+->4+ yrast transitions in 90Zr (to complete the systematics along N=50) have been determined. This made possible a complete study of the seniority scheme in the proton g9/2. The results on the obtained reduced transition probabilities for the 92Mo and 94Ru (and 90Zr, for the sake of completeness) have been interpreted on the basis of realistic shell-model predictions in the f5/2, p3/2, p1/2, g9/2 proton valence space, allowing also for the comparison of the nuclear structure trends between the valence-mirror symmetry partners. Additionally, part of this Thesis is devoted to the performance of state-of-the art high-resolution gamma-ray spectroscopy detector used in the experiment. AGATA consists of high-fold segmented high purity Ge detectors and a front-end electronics, based on advanced digital signal processing techniques. This techniques permit the extraction of the energy, time and spatial information of the Ge detector signals in order to track and reconstruct the gamma-rays inside of a Ge detector. As a result of these innovative techniques, AGATA is a position sensitive high-resolution gamma spectrometer capable of operating in extreme measuring conditions (high counting rates and high background) in combination of complementary detectors and devices, for example to measure charged particles or neutrons. The characterization of AGATA is provided based on the analysis of radioactive source and in-beam data taken with 23 segmented crystals.