The 3He(alpha,gamma)7Be reaction presently represents the largest nuclear uncertainty in the predicted solar neutrino flux and has important implications on the big bang nucleosynthesis, i.e., the production of primordial 7Li. We present here the results of an experiment using the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be ejectiles. In addition, off-beam activation and coincidence gamma-ray measurements were performed at selected energies. At energies above 1 MeV a large discrepancy compared to previous results is observed both in the absolute value and in the energy dependence of the cross section. Based on the available data and models, a robust estimate of the cross section at the astrophysical relevant energies is proposed.
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http://dx.doi.org/10.1103/PhysRevLett.102.232502 | DOI Listing |
Nat Commun
November 2024
Laboratoire Collisions Agrégats Réactivité (LCAR/FERMI), UMR5589, UniversitéToulouse III - Paul Sabatier and CNRS, 118 Route de Narbonne, F-31062, Toulouse, France.
The effective control of atomic coherence with cold atoms has made atom interferometry an essential tool for quantum sensors and precision measurements. The performance of these interferometers is closely related to the operation of large wave packet separations. We present here a novel approach for atomic beam splitters based on the stroboscopic stabilization of quantum states in an accelerated optical lattice.
View Article and Find Full Text PDFResusc Plus
December 2024
Department of Emergency Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China.
Aim: This study aimed to compare the quality of compressions in supine cardiopulmonary resuscitation (CPR) and prone CPR by performing chest compressions on a manikin. Evaluating the effect of prone CPR using different hand and body position on the quality of manual chest compressions and fatigue of participants.
Methods: After completing 2 min of chest compression in the supine position (Supine Group), 25 participants randomly performed three sets of 2-minutes chest compressions on a prone position manikin.
Front Chem
September 2024
GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany.
Phys Rev Lett
July 2024
INFN, Sezione di Pavia, Pavia, Italy.
The ALICE Collaboration reports the measurement of semi-inclusive distributions of charged-particle jets recoiling from a high transverse momentum (high p_{T}) hadron trigger in proton-proton and central Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV. A data-driven statistical method is used to mitigate the large uncorrelated background in central Pb-Pb collisions.
View Article and Find Full Text PDFBioinspir Biomim
August 2024
Department of Aerospace Engineering, The University of Alabama, Tuscaloosa, AL 35487, United States of America.
This smooth flat experimental study investigates the capability of mako shark scales to control flow separation when placed downstream of the onset of turbulent boundary layer separation and within the reattachment region. The objective of the study is to validate the hypothesis that the shark scales' bristling and recoiling would prevent the flow separation on the flank region (the fastest flow region) of the shark. A rotating cylinder was used to induce an adverse pressure gradient over a flat plate to produce a region of separated flow where the shark skin specimen was mounted.
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