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International audience; The gyromagnetic factor of the low-lying Ex=684.10(19)keV isomeric state of the nucleus 99Mo was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of Jπ=11/2−, with a half-life of T1/2=742(13)ns. The state of interest was populated and spin-aligned via a single-neutron transfer on a highly enriched 98Mo target. A magnetic moment μexpt.=−0.627(20)μN was obtained. This result is far from the Schmidt value expected for a pure single-particle νh11/2 state. A comparison of experimental spectroscopic properties of this nucleus is made with results of multishell Interacting boson-fermion Model (IBFM-1) calculations. In this approach, the Jπ=11/2− isomeric state in 99Mo has a pure νh11/2 configuration. Its magnetic moment, as well as that of other two excited states could be reasonably well reproduced by reducing the free neutron spin g factor with a quenching factor of 0.45. This low value is not appropriate only for this case, similar values for the quenching factor being also required in order to describe magnetic moments in other nuclei from the same mass region

Reliable neutron-induced reaction cross sections of unstable nuclei are essential for nuclear astrophysics and applications but their direct measurement is often impossible. The surrogate-reaction method is one of the most promising alternatives to access these cross sections. However, its use is hampered by the need to account for the differences between the angular momenta and parities populated by the surrogate and the neutron-induced reactions. Here we show that it is possible to overcome this limitation and infer for the first time both the neutron-induced fission and radiative-capture cross sections of 239Pu. This was achieved by combining simultaneously-measured fission and gamma-emission probabilities for the 240Pu(4He,4He') surrogate reaction with a calculation of the angular-momentum and parity distributions populated in this reaction.

International audience; Cross sections for neutron-induced reactions of short-lived nuclei are essential for nuclear astrophysics since these reactions in the stars are responsible for the production of most heavy elements in the universe. These reactions are also key in applied domains like energy production and medicine. Nevertheless, neutron-induced cross-section measurements can be extremely challenging or even impossible to perform due to the radioactivity of the targets involved. Indirect measurements through the surrogate-reaction method can help to overcome these difficulties. The surrogate-reaction method relies on the use of an alternative reaction that will lead to the formation of the same excited nucleus as in the neutron-induced reaction of interest. The decay probabilities (for fission, neutron and gamma-ray emission) of the nucleus produced via the surrogate reaction allow one to constrain models and the prediction of the desired neutron cross sections. We propose to perform surrogate reaction measurements in inverse kinematics at heavy-ion storage rings, in particular at the CRYRING@ESR of the GSI/FAIR facility. We present the conceptual idea of the most promising setup to measure for the first time simultaneously the fission, neutron and gamma-ray emission probabilities. The results of the first simulations considering the 238U(d,d’) reaction are shown, as well as new technical developments that are being carried out towards this set-u

International audience; Resonance energies Eλ, neutron widths Γn,λ, and radiation widths Γγ,λ for the compound system $^{175}$Lu+n were determined up to 1 keV from time-of-flight data reported in literature and recently measured at the GELINA facility of JRC-Geel (Belgium). The statistical analysis of the obtained resonance parameters provides an s-wave neutron strength function [S0=1.96(8)], mean level spacing [D0=3.24(9)eV], and average radiation width (〈Γγ0〉=61.3(59)meV) which are substantially different from those compiled in libraries dedicated to statistical calculations. The largest difference lies on the average radiation width, for which a value of 77(5) meV is recommended. $^{175}$Lu neutron cross sections were calculated with the talys code by using our s-wave average parameters as constraints. At kT=30keV, we obtain a total neutron capture cross section equal to 1125(62) mbarns, confirming the lower values reported in the 1990s.

Objective: Patients with Cushing's syndrome (CS) have increased mortality. The aim of this study was to evaluate the causes and time of death in a large cohort of patients with CS and to establish factors associated with increased mortality. Methods: In this cohort study, we analyzed 1564 patients included in the European Registry on CS (ERCUSYN); 1045 (67%) had pituitary-dependent CS, 385 (25%) adrenal-dependent CS, 89 (5%) had an ectopic source and 45 (3%) other causes. The median (IQR) overall follow-up time in ERCUSYN was 2.7 (1.2-5.5) years. Results: Forty-nine patients had died at the time of the analysis; 23 (47%) with pituitary-dependent CS, 6 (12%) with adrenal-dependent CS, 18 (37%) with ectopic CS and two (4%) with CS due to other causes. Of 42 patients whose cause of death was known, 15 (36%) died due to progression of the underlying disease, 13 (31%) due to infections, 7 (17%) due to cardiovascular or cerebrovascular disease and 2 due to pulmonary embolism. The commonest cause of death in patients with pituitary-dependent CS and adrenal-dependent CS were infectious diseases (n = 8) and progression of the underlying tumor (n = 10) in patients with ectopic CS. Patients who had died were older and more often males, and had more frequently muscle weakness, diabetes mellitus and ectopic CS, compared to survivors. Of 49 deceased patients, 22 (45%) died within 90 days from start of treatment and 5 (10%) before any treatment was given. The commonest cause of deaths in these 27 patients were infections (n = 10; 37%). In a regression analysis, age, ectopic CS and active disease were independently associated with overall death before and within 90 days from the start of treatment. Conclusion: Mortality rate was highest in patients with ectopic CS. Infectious diseases the commonest cause of death soon after diagnosis, emphasizing the need for careful vigilance at that time, especially in patients presenting with concomitant diabetes mellitus.

International audience; We report the measurement of a neutron radiative cross section on a target with a high gamma activity, at the Los Alamos DANCE detector (Detector for Advanced Neutron Capture Experiments) for the first time. The (n,γ) reaction properties of the unstable Lu173 isotope were studied. Two experimental campaigns were needed to determine the Lu173(n,γ) cross section. They were performed at the Los Alamos Neutron Science Center (LANSCE) spallation neutron source facility. To this end, two targets were produced from an Hf sample using successively proton irradiation and chemical separations. They were composed of Lu173,Lu174, and Lu175 isotopes. The two measurements were conducted at two-year intervals, taking advantage of the difference of the isotopic decay lifetimes in order to identify resonances from the Lu173(n,γ) and Lu174(n,γ) reactions. Just over one hundred new resonances were observed, the majority of which come from the Lu173(n,γ) reaction. Only a few of them were assigned to the Lu174(n,γ) reaction. As regards the Lu173(n,γ) reaction, the radiative neutron capture cross section was determined over the energy range from thermal neutron up to 200 eV. The parameters of resonances in the resolved resonance region were extracted with the sammy code while calculations with talys determined the capture cross section in the unresolved resonances region. At the keV region, we performed standard talys calculations as well as other microscopic investigations by substituting the standard talys photon strength function by another one from QRPA models.

Fission and gamma-emission probabilities induced by transfer or inelastic scattering reactions with light projectile nuclei are very valuable quantities for constraining the models that describe the de-excitation of heavy nuclei. We have developed an experimental set-up that allows us to simultaneously measure fission and gamma-emission probabilities. The measurement of the gamma-emission probability at excitation energies where the fission channel is open is challenging due to the intense background of gamma rays emitted by the fission fragments. We discuss the procedure to subtract such a background and the constraints that this subtraction and other experimental conditions put on the set up. We show that our set-up complies with these constraints., 18 pages, 10 figures