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Feasibility, design and sensitivity studies on innovative nuclear reactors that could address the issue of nuclear waste transmutation using fuels enriched in minor actinides, require high accuracy cross section data for a variety of neutron-induced reactions from thermal energies to several tens of MeV. The isotope 241Am (T1/2= 433 years) is present in high-level nuclear waste (HLW), representing about 1.8 % of the actinide mass in spent PWR UOx fuel. Its importance increases with cooling time due to additional production from the β-decay of 241Pu with a half-life of 14.3 years. The production rate of 241 Am in conventional reactors, including its further accumulation through the decay of 241Pu and its destruction through transmutation/incineration are very important parameters for the design of any recycling solution. In the present work, the 241 Am(n,f) reaction cross-section was measured using Micromegas detectors at the Experimental Area 2 of the n_TOF facility at CERN. For the measurement, the 235U(n,f) and 238U(n,f) reference reactions were used for the determination of the neutron flux. In the present work an overview of the experimental setup and the adopted data analysis techniques is given along with preliminary results.
We have analysed the microseismic activity within the Rwenzori Mountains area in the western branch of the East African Rift. Seismogram recordings from a temporary array of up to 27 stations reveal approximately 800 events per month with local magnitudes ranging from –0.5 to 5.1. The earthquake distribution is highly heterogeneous. The majority of located events lie within faults zones to the East and West of the Rwenzoris with the highest seismic activity observed in the northeastern area, where the mountains are in contact with the rift shoulders. The hypocentral depth distribution exhibits a pronounced peak of seismic energy release at 15 km depth. The maximum extent of seismicity ranges from 20 to 32 km and correlates well with Moho depths that were derived from teleseismic receiver functions. We observe two general features: (i) beneath the rift shoulders seismicity extends from the surface down to ca. 30 km depth; (ii) beneath the rift valley seismicity is confined to depths greater than 10 km. From the observations there is no indication for a crustal root beneath the Rwenzori Mountains. The magnitude frequency distribution reveals a b-value of 1.1, which is consistent with the hypothesis that part of the seismicity is caused by magmatic processes within the crust. Fault plane solutions of 304 events were derived from P-polarities and SV/P amplitude ratios. More than 70 % of the source mechanisms exhibit pure or predominantly normal faulting. T-axis trends are highly uniform and oriented WNW-ESE, which is perpendicular to the rift axis and in good agreement with kinematic rift models. At the northernmost part of the region we observe a rotation of the T-axis trends to NEN-SWS, which may be indicative of a local perturbation of the regional stress field.
We have analysed the microseismic activity within the Rwenzori Mountains area in the western branch of the East African Rift. Seismogram recordings from a temporary array of up to 27 stations reveal approximately 800 events per month with local magnitudes ranging from –0.5 to 5.1. The earthquake distribution is highly heterogeneous. The majority of located events lie within faults zones to the east and west of the Rwenzoris with the highest seismic activity observed in the northeastern area, where the mountains are in contact with the rift shoulders. The hypocentral depth distribution exhibits a pronounced peak of seismic energy release at 15 km depth. The maximum extent of seismicity ranges from 20 to 32 km and correlates well with Moho depths that were derived from teleseismic receiver functions. We observe two general features: (i) beneath the rift shoulders, seismicity extends from the surface down to ca. 30 km depth; (ii) beneath the rift valley, seismicity is confined to depths greater than 10 km. From the observations there is no indication for a crustal root beneath the Rwenzori Mountains. The magnitude frequency distribution reveals a b-value of 1.1, which is consistent with the hypothesis that part of the seismicity is caused by magmatic processes within the crust. Fault plane solutions of 304 events were derived from P-polarities and SV/P amplitude ratios. More than 70 % of the source mechanisms exhibit pure or predominantly normal faulting. T-axis trends are highly uniform and oriented WNW–ESE, which is perpendicular to the rift axis and in good agreement with kinematic rift models. At the northernmost part of the region we observe a rotation of the T-axis trends to NEN–SWS, which may be indicative of a local perturbation of the regional stress field.
Aims: To compare the effects of Ayurvedic and conventional nutritional therapy in patients with irritable bowel syndrome (IBS). Methods: Sixty-nine patients with IBS were randomized to Ayurvedic (n = 35) or conventional nutritional therapy according to the recommendations of the German Nutrition Society including the low-FODMAP diet (n = 34). Study visits took place at baseline and after 1, 3, and 6 months. The primary outcome was IBS symptom severity (IBS-SSS) after 3 months; secondary outcomes included stress (CPSS), anxiety and depression (HADS), well-being (WHO-5) and IBS-specific quality of life (IBS-QOL). A repeated measures general linear model (GLM) for intent-to-treat-analyses was applied in this explorative study. Results: After 3 months, estimated marginal means for IBS-SSS reductions were 123.8 [95% confidence interval (95% CI) = 92.8–154.9; p < 0.001] in the Ayurvedic and 72.7 (95% CI = 38.8–106.7; p < 0.001) in the conventional group. The IBS-SSS reduction was significantly higher in the Ayurveda group compared to the conventional therapy group (estimated marginal mean = 51.1; 95% CI = 3.8–98.5; p = 0.035) and clinically meaningful. Sixty-eight percentage of the variance in IBS-SSS reduction after 3 months can be explained by treatment, 6.5% by patients' expectations for their therapies and 23.4% by IBS-SSS at pre-intervention. Both therapies are equivalent in their contribution to the outcome variance. The higher the IBS-SSS score at pre-intervention and the larger the patients' expectations, the greater the IBS-SSS reduction. There were no significant group differences in any secondary outcome measures. No serious adverse events occurred in either group. Conclusion: Patients with IBS seem to benefit significantly from Ayurvedic or conventional nutritional therapy. The results warrant further studies with longer-term follow-ups and larger sample sizes. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03019861, identifier: NCT03019861.
An accurate measurement of the 140Ce(n,γ) energy-dependent cross-section was performed at the n_TOF facility at CERN. This cross-section is of great importance because it represents a bottleneck for the s-process nucleosynthesis and determines to a large extent the cerium abundance in stars. The measurement was motivated by the significant difference between the cerium abundance measured in globular clusters and the value predicted by theoretical stellar models. This discrepancy can be ascribed to an overestimation of the 140Ce capture cross-section due to a lack of accurate nuclear data. For this measurement, we used a sample of cerium oxide enriched in 140Ce to 99.4%. The experimental apparatus consisted of four deuterated benzene liquid scintillator detectors, which allowed us to overcome the difficulties present in the previous measurements, thanks to their very low neutron sensitivity. The accurate analysis of the p-wave resonances and the calculation of their average parameters are fundamental to improve the evaluation of the 140Ce Maxwellian-averaged cross-section.
Eine materialreiche, ansprechend illustrierte und mit zahlreichen Beispielen ausgestattete Einführung in die Lyrikvermittlung liegt hier vor, die sich vorrangig an die Lehrenden im Primarbereich richtet. Die Stärke der Darstellung liegt eindeutig im Praxisbezug, viele Modelle für konkrete Unterrichtsplanung und -durchführung können hier nachgelesen und dann erprobt werden, die Ausrichtung folgt dezidiert handlungs- und produktionsorientierten Methoden, wie man es von Franz-Josef Payrhuber auch nicht anders erwartet. Die Gliederung ist ausgerichtet an vier "Blickpunkten": Zunächst werden "Formen" präsentiert, der umfangreiche zweite Teil widmet sich den "Methoden", der dritte präsentiert einzelne "Themen" und der letzte nimmt "Autoren" in den Blick. Abgeschlossen wird der Band durch ein umfassendes Literaturverzeichnis. ...
Die vorliegende Werkbiographie Mira Lobes ist Ergebnis eines Forschungsprojekts am Ludwig Boltzmann Institut für Geschichte und Theorie der Biographie in Wien. Daraus entstanden eine Ausstellung im Jahre 2014/15 mit dem Titel "Ich bin ich. Mira Lobe und Susi Weigel" anlässlich des hundertsten Geburtstags der Schriftstellerin, die der Verfasser mitkuratiert hat. Seine Forschungen wurden 2014 als Dissertation in Wien vorgelegt. Es ist die erste umfassende Darstellung zu Leben und Werk der erfolgreichen und kanonisierten Autorin, vermag über den Blick auf die Einzelperson hinaus außerdem wichtige Erkenntnisse über das kinderliterarische Leben in Österreich seit den 1950er Jahren zu vermitteln. Denn neben den Ausführungen zu Mira Lobe selbst berücksichtigt Huemer eine Vielzahl anderer Aspekte: die Publikationswege Lobes, die Verlagslandschaft, die IllustratorInnen ihrer Bücher wie auch zum Teil die Rezeption der Werke. Dies alles wurde erreicht durch eine akribische Auswertung des recht verstreuten Nachlasses sowie durch zahlreiche Interviews mit noch lebenden Weggefährten, die eine wichtige Rolle im Leben der Autorin gespielt haben. ...
Neutron capture on 241Am plays an important role in the nuclear energy production and also provides valuable information for the improvement of nuclear models and the statistical interpretation of the nuclear properties. A new experiment to measure the 241Am(n, γ) cross section in the thermal region and the first few resonances below 10 eV has been carried out at EAR2 of the n_TOF facility at CERN. Three neutron-insensitive C6D6 detectors have been used to measure the neutron-capture gamma cascade as a function of the neutron time of flight, and then deduce the neutron capture yield. Preliminary results will be presented and compared with previously obtained results at the same facility in EAR1. In EAR1 the gamma-ray background at thermal energies was about 90% of the signal while in EAR2 is up to a 25 factor much more favorable signal to noise ratio. We also extended the low energy limit down to subthermal energies. This measurement will allow a comparison with neutron capture measurements conducted at reactors and using a different experimental technique.
Objectives: Immune checkpoint inhibitors have become the standard of care for metastatic non–small-cell lung cancer (NSCLC) progressing during or after platinum-based chemotherapy. Real-world clinical practice tends to represent more diverse patient characteristics than randomized clinical trials. We sought to evaluate overall survival (OS) outcomes in the total study population and in key subsets of patients who received nivolumab for previously treated advanced NSCLC in real-world settings in France, Germany, or Canada.
Materials and methods: Data were pooled from two prospective observational cohort studies, EVIDENS and ENLARGE, and a retrospective registry in Canada. Patients included in this analysis were aged ≥18 years, had stage IIIB/IV NSCLC, and received nivolumab after at least one prior line of systemic therapy. OS was estimated in the pooled population and in various subgroups using the Kaplan-Meier method. Timing of data collection varied across cohorts (2015–2019).
Results: Of the 2585 patients included in this analyses, 1235 (47.8 %) were treated in France, 881 (34.1 %) in Germany, and 469 (18.1 %) in Canada. Median OS for the total study population was 11.3 months (95 % CI: 10.5–12.2); this was similar across France, Germany, and Canada. The OS rate was 49 % at 1 year and 28 % at 2 years for the total study population. In univariable Cox analyses, the presence of epidermal growth factor receptor mutations in nonsquamous disease, liver, or bone metastases were associated with significantly shorter OS, whereas tumor programmed death ligand 1 expression and Eastern Cooperative Oncology Group performance status 0–1 were associated with significantly prolonged OS. Similar OS was noted across subgroups of age and prior lines of therapy.
Conclusion: OS rates in patients receiving nivolumab for previously treated advanced NSCLC in real-world clinical practice closely mirrored those in phase 3 studies, suggesting similar effectiveness of nivolumab in clinical trials and clinical practice.
Previous research indicates that anxiety disorders are characterized by an overgeneralization of conditioned fear as compared with healthy participants. Therefore, fear generalization is considered a key mechanism for the development of anxiety disorders. However, systematic investigations on the variance in fear generalization are lacking. Therefore, the current study aims at identifying distinctive phenotypes of fear generalization among healthy participants. To this end, 1175 participants completed a differential fear conditioning phase followed by a generalization test. To identify patterns of fear generalization, we used a k-means clustering algorithm based on individual arousal generalization gradients. Subsequently, we examined the reliability and validity of the clusters and phenotypical differences between subgroups on the basis of psychometric data and markers of fear expression. Cluster analysis reliably revealed five clusters that systematically differed in mean responses, differentiation between conditioned threat and safety, and linearity of the generalization gradients, though mean response levels accounted for most variance. Remarkably, the patterns of mean responses were already evident during fear acquisition and corresponded most closely to psychometric measures of anxiety traits. The identified clusters reliably described subgroups of healthy individuals with distinct response characteristics in a fear generalization test. Following a dimensional view of psychopathology, these clusters likely delineate risk factors for anxiety disorders. As crucial group characteristics were already evident during fear acquisition, our results emphasize the importance of average fear responses and differentiation between conditioned threat and safety as risk factors for anxiety disorders.
Rezensionen [2017]
(2017)
156 Ansari, Christine (Hrsg.): Adoleszenz in Medienkontexten. Literaturrezeption, Medienwirkung und Jugendmedienschutz (judith mathez)
158 Bachmann, Christian A. / Emans, Laura / Schmitz-Emans, Monika (Hrsg.): Bewegungsbücher. Spielformen, Poetiken, Konstellationen (gundel mattenklott)
160 Ballis, Anja /Schlachter, Birgit (Hrsg.): Schätze der Kinder- und Jugendliteratur wiederentdeckt. Frühe Lektüreerfahrung und Kanonbildung im akademischen Kontext (ernst seibert)
162 Benner, Julia: Federkrieg. Kinder- und Jugendliteratur gegen den Nationalsozialismus 1933 – 1945 (linde storm)
164 Born, Stefan: Allgemeinliterarische Adoleszenzromane. Untersuchungen zu Herrndorf, Regener, Strunk, Kehlmann und anderen (lena hoffmann)
166 Börnchen, Stefan: Poetik der Linie. Wilhelm Busch, Max und Moritz und die Tradition (lukas sarvari)
168 Burwitz-Melzer, Eva /O’Sullivan, Emer (Hrsg.): Einfachheit in der Kinder- und Jugendliteratur. Ein Gewinn für den Fremdsprachenunterricht (roland alexander issler)
169 Emde, Oliver /Möller, Lukas /Wicke, Andreas (Hrsg.): Von »Bibi Blocksberg« bis »TKKG«. Kinderhörspiele aus gesellschafts- und kulturwissenschaftlicher Perspektive (anika ullmann)
171 Ferstl, Paul /Walach, Thomas / Zahlmann, Stefan (Hrsg.): Fantasy Studies (maren bonacker)
173 Giesa, Felix: Graphisches Erzählen von Adoleszenz. Deutschsprachige Autorencomics nach 2000 (michael staiger)
175 Hahn, Heidi / Laudenberg, Beate / Rösch, Heidi (Hrsg.): »Wörter raus!?« Zur Debatte um eine diskriminierungsfreie Sprache im Kinderbuch (julia benner)
177 Haug, Christine / Frimmel, Johannes (Hrsg.): Schulbücher um 1800. Ein Spezialmarkt zwischen staatlichem, volksaufklärerischem und konfessionellem Auftrag (ortwin beisbart)
179 Hollerweger, Elisabeth /Stemmann, Anna (Hrsg.): Narrative Delikatessen. Kulturelle Dimensionen von Ernährung (sonja loidl)
180 Hopp, Margarete: Sterben, Tod und Trauer im Bilderbuch seit 1945 (iris schäfer)
182 Huemer, Georg: Mira Lobe. Doyenne der österreichischen Kinder- und Jugendliteratur (andreas schumann)
183 Josting, Petra (Hrsg.): Andreas Steinhöfel, Bielefelder Poet in Residence 2014 (heinke kilian)
185 Josting, Petra /Roeder, Caroline /Dettmar, Ute (Hrsg.): Immer Trouble mit Gender. Genderperspektiven in Kinder- und Jugendliteraturforschung und -medien (jana mikota)
187 Kurwinkel, Tobias /Schmerheim, Philipp /Sevi, Annika (Hrsg.): Michael Ende intermedial. Von Lokomotivführern, Glücksdrachen und dem (phantastischen) Spiel mit Mediengrenzen (michael stierstorfer)
188 Mikota, Jana / Pecher, Claudia Maria / von Glasenapp, Gabriele (Hrsg.): Literarisch-kulturelle Begegnungen mit dem Judentum. Beiträge zur kinderliterarischen Fachöffentlichkeit (susanne blumesberger)
190 Müller, Karla / Decker, Jan-Oliver / Krah, Hans / Schilcher, Anita (Hrsg.): Genderkompetenz mit Kinder- und Jugendliteratur entwickeln: Grundlagen – Analysen – Modelle (annette kliewer)
192 Nikolajeva, Maria: Reading for Learning. Cognitive Approaches to Children’s Literature (sabine fuchs)
194 Paul, Lissa / Johnston, Rosemary R. / Short, Emma (Hrsg.):Children’s Literature and Culture of the First World War.(julia benner)
195 Payrhuber, Franz-Josef / Meier, Bernhard(Hrsg.): Franz, Kurt: Kinderlyrik. Geschichte, Formen, Rezeption(ludger scherer)
197 Payrhuber, Franz-Josef:Gedichte entdecken. Wege zu Gedichten in der ersten bis sechsten Klasse (andreas schumann)
198 Pohlmann, Carola (Hrsg): Kinder- und Jugendliteratur. Sammeln und Erwerben (wolfgang wangerin)
200 Pompe, Anja (Hrsg): Kind und Gedicht. Wie wir lesen lernen (heinz-jürgen kliewer)
202 Preindl, Nadia:Russische Kinderliteratur im europäischen Exil der Zwischenkriegszeit (verena rutschmann)
204 Richter, Karin: Die Kinder- und Jugend-literatur der DDR. Entwicklungslinien – Themen und Genres. Autorenporträts und Textanalysen (maria becker)
206 Riemhofer, Andra:Interkulturelle Kinder- und Jugendliteratur in Deutschland. Lesen auf eigene Gefahr (roger meyer)
208Roeder, Caroline (Hrsg.): Himmel und Hölle. Raumerkundungen – interdisziplinär & in schulischer Praxis (claudia blei-hoch)
210 Ruzicka Kenfel, Vejka (Hrsg.): New Trends in Children’s Literature Research. Twenty-first Century Approaches (2000–2012) from the University of Vigo (Spain) (susanne blumesberger)
212 Schäfer, Iris:Von der Hysterie zur Magersucht. Adoleszenz und Krankheit in Romanen und Erzählungen der Jahrhundert- und der Jahrtausendwende (philipp schmerheim)
214 Scherer, Gabriela / Volz, Steffen (Hrsg.): Im Bildungsfokus: Bilderbuchrezeptions-forschung (margarete hopp)
216 Schmitt, Susann Sophie:Nachwuchs für die Literatur. Kinder- und Jugendprogramme ausgewählter Literaturhäuser Deutschlands, Österreichs und der Schweiz (renate grubert)
217 Seelinger Trites, Roberta:Literary Conceptu-alizations of Growth. Metaphors and Cogni-tion in Adolescent Literature (iris schäfer)
219 Seifert, Martina:Die Bilderfalle. Kanada in der deutschsprachigen Kinder- und Jugend-literatur: Produktion und Rezeption (sabine planka)
222 Stein, Daniel / Thon, Jan-Noël (Hrsg.): From Comic Strips to Graphic Novels. Contributions to the Theory and History of Graphic Narrative (anna stemmann)
223 Tomberg, Markus (Hrsg.): Alle wichtigen Bücher handeln von Gott. Religiöse Spuren in aktueller Kinder- und Jugendliteratur (martin anker)
The neutron sensitivity of the C6D6 detector setup used at n_TOF facility for capture measurements has been studied by means of detailed GEANT4 simulations. A realistic software replica of the entire n_TOF experimental hall, including the neutron beam line, sample, detector supports and the walls of the experimental area has been implemented in the simulations. The simulations have been analyzed in the same manner as experimental data, in particular by applying the Pulse Height Weighting Technique. The simulations have been validated against a measurement of the neutron background performed with a natC sample, showing an excellent agreement above 1 keV. At lower energies, an additional component in the measured natC yield has been discovered, which prevents the use of natC data for neutron background estimates at neutron energies below a few hundred eV. The origin and time structure of the neutron background have been derived from the simulations. Examples of the neutron background for two different samples are demonstrating the important role of accurate simulations of the neutron background in capture cross-section measurements.
The neutron capture cross section of 58Ni was measured at the neutron time of flight facility n_TOF at CERN, from 27 meV to 400 keV neutron energy. Special care has been taken to identify all the possible sources of background, with the so-called neutron background obtained for the first time using high-precision GEANT4 simulations. The energy range up to 122 keV was treated as the resolved resonance region, where 51 resonances were identified and analyzed by a multilevel R-matrix code SAMMY. Above 122 keV the code SESH was used in analyzing the unresolved resonance region of the capture yield. Maxwellian averaged cross sections were calculated in the temperature range of kT = 5 – 100 keV, and their astrophysical implications were investigated.
Since the start of its operation in 2001, based on an idea of Prof. Carlo Rubbia [1], the neutron time of-flight facility of CERN, n_TOF, has become one of the most forefront neutron facilities in the world for wide-energy spectrum neutron cross section measurements. Thanks to the combination of excellent neutron energy resolution and high instantaneous neutron flux available in the two experimental areas, the second of which has been constructed in 2014, n_TOF is providing a wealth of new data on neutron-induced reactions of interest for nuclear astrophysics, advanced nuclear technologies and medical applications. The unique features of the facility will continue to be exploited in the future, to perform challenging new measurements addressing the still open issues and long-standing quests in the field of neutron physics. In this document the main characteristics of the n_TOF facility and their relevance for neutron studies in the different areas of research will be outlined, addressing the possible future contribution of n_TOF in the fields of nuclear astrophysics, nuclear technologies and medical applications. In addition, the future perspectives of the facility will be described including the upgrade of the spallation target, the setup of an imaging installation and the construction of a new irradiation area.
The neutron capture cross section of 154Gd was measured from 1 eV to 300 keV in the experimental area located 185 m from the CERN n_TOF neutron spallation source, using a metallic sample of gadolinium, enriched to 67% in 154Gd. The capture measurement, performed with four C6D6 scintillation detectors, has been complemented by a transmission measurement performed at the GELINA time-of-flight facility (JRC-Geel), thus minimising the uncertainty related to sample composition. An accurate Maxwellian averaged capture cross section (MACS) was deduced over the temperature range of interest for s process nucleosynthesis modelling. We report a value of 880(50) mb for the MACS at kT = 30 keV, significantly lower compared to values available in literature. The new adopted 154Gd(n,γ) cross section reduces the discrepancy between observed and calculated solar s-only isotopic abundances predicted by s-process nucleosynthesis models.
Setup for the measurement of the 235U(n,f) cross section relative to n-p scattering up to 1 GeV
(2020)
The neutron induced fission of 235U is extensively used as a reference for neutron fluence measurements in various applications, ranging from the investigation of the biological effectiveness of high energy neutrons, to the measurement of high energy neutron cross sections of relevance for accelerator driven nuclear systems. Despite its widespread use, no data exist on neutron induced fission of 235U above 200 MeV. The neutron facility n_TOF offers the possibility to improve the situation. The measurement of 235U(n,f) relative to the differential n-p scattering cross-section, was carried out in September 2018 with the aim of providing accurate and precise cross section data in the energy range from 10 MeV up to 1 GeV. In such measurements, Recoil Proton Telescopes (RPTs) are used to measure the neutron flux while the fission events are detected and counted with dedicated detectors. In this paper the measurement campaign and the experimental set-up are illustrated.
The study of neutron-induced reactions on actinides is of considerable importance for the design of advanced nuclear systems and alternative fuel cycles. Specifically, 230Th is produced from the α-decay of 234U as a byproduct of the 232Th/233U fuel cycle, thus the accurate knowledge of its fission cross section is strongly required. However, few experimental datasets exist in literature with large deviations among them, covering the energy range between 0.2 to 25 MeV. In addition, the study of the 230Th(n,f) cross-section is of great interest in the research on the fission process related to the structure of the fission barriers. Previous measurements have revealed a large resonance at En=715 keV and additional fine structures, but with high discrepancies among the cross-section values of these measurements. This contribution presents preliminary results of the 230Th(n,f) cross-section measurements at the CERN n_TOF facility. The high purity targets of the natural, but very rare isotope 230Th, were produced at JRC-Geel in Belgium. The measurements were performed at both experimental areas (EAR-1 and EAR-2) of the n_TOF facility, covering a very broad energy range from thermal up to at least 100 MeV. The experimental setup was based on Micromegas detectors with the 235U(n,f) and 238U(n,f) reaction cross-sections used as reference.
New measurements of the 7Be(n,α)4He and 7Be(n,p)7Li reaction cross sections from thermal to keV neutron energies have been recently performed at CERN/n_TOF. Based on the new experimental results, astrophysical reaction rates have been derived for both reactions, including a proper evaluation of their uncertainties in the thermal energy range of interest for big bang nucleosynthesis studies. The new estimate of the 7Be destruction rate, based on these new results, yields a decrease of the predicted cosmological 7Li abundance insufficient to provide a viable solution to the cosmological lithium problem.
We have measured the γ-rays following neutron capture on 240Pu and 244 Cm at the n_TOF facility at CERN with the Total Absorption Calorimeter (TAC) and with C6D6 organic scintillators. The TAC is made of 40 BaF2 crystals operating in coincidence and covering almost the entire solid angle. This allows to obtain information concerning the energy spectra and the multiplicity of the measured capture γ-ray cascades. Additional information is also obtained from the C6D6 detectors. We have analyzed the measured data in order to draw conclusions about the Photon Strength Functions (PSFs) of 241Pu and 245Cm below their neutron separation energies. The analysis has been performed by fitting the PSFs to the experimental results, using the differential evolution method, in order to find neutron capture cascades capable of reproducing at the same time a great variety of deposited energy spectra.