Search results for "nuclear physics"
showing 10 items of 5307 documents
Recent Borexino results and prospects for the near future
2015
The Borexino experiment, located in the Gran Sasso National Laboratory, is an organic liquid scintillator detector conceived for the real time spectroscopy of low energy solar neutrinos. The data taking campaign phase I (2007 - 2010) has allowed the first independent measurements of 7Be, 8B and pep fluxes as well as the first measurement of anti-neutrinos from the earth. After a purification of the scintillator, Borexino is now in phase II since 2011. We review here the recent results achieved during 2013, concerning the seasonal modulation in the 7Be signal, the study of cosmogenic backgrounds and the updated measurement of geo-neutrinos. We also review the upcoming measurements from phase…
Recent Borexino results and perspectives of the SOX measurement
2017
International audience; Borexino is a liquid scintillator detector sited underground in the Laboratori Nazionali del Gran Sasso (Italy). Its physics program, until the end of this year, is focussed on the study of solar neutrinos, in particular from the Beryllium, pp, pep and CNO fusion reactions. Knowing the reaction chains in the sun provides insights towards physics disciplines such as astrophysics (star physics, star formation, etc.), astroparticle and particle physics. Phase II started in 2011 and its aim is to improve the phase I results, in particular the measurements of the neutrino fluxes from the pep and CNO processes. By the end of this year, data taking from the sun will be over…
Flavour Separation of Helicity Distributions from Deep Inelastic Muon-Deuteron Scattering
2009
We present a LO evaluation of helicity densities of valence, \Delta u_v+\Delta d_v, non-strange sea, \Delta\bar{u}+\Delta\bar{d}, and strange quarks, \Delta s (assumed to be equal to \Delta\bar{s}). They have been obtained from the inclusive asymmetry A_{3,d} and the semi-inclusive asymmetries A^{\pi+}_{1,d}, A^{\pi-}_{1,d}, A^{K+}_{1,d}, A^{K-}_{1,d} measured in polarised deep inelastic muon-deuteron scattering. The full deuteron statistics of COMPASS (years 2002-2004 and 2006) has been used. The data cover the range Q^2 > 1 (GeV/c)^2 and 0.004<x<0.3. Both non-strange densities are found to be in a good agreement with previous measurements. The distribution of \Delta s(x) is compatible wit…
FIRST MEASUREMENT OF THE STRANGE QUARK ASYMMETRY AT THE Z(0) PEAK
1995
A measurement of the strange quark forward-backward asymmetry at the Z0 peak was performed using 718,000 multihadronic Z0 decays collected by the DELPHI detector at LEP in 1992. The s-quark was tagged by the presence of high momentum charged kaons identified by the Ring Imaging Cherenkov detector and by Λ0;s decaying into pπ-. The s-quark purity obtained was estimated for the two hadrons to be 43%. The average s-quark asymmetry was found to be 0.131±0.035 (stat.) ±0.013 (syst.). The forward-backward asymmetry was measured for unresolved d-and s-quarks, tagged by the detection of a high energy neutron or neutral kaon in the Hadron Calorimeter. The combined d-and s-quark purity was 69% and th…
Neutronic and photonic analysis of the water-cooled Pb17Li test blanket module for ITER-FEAT
2002
Abstract Within the European Fusion Technology Program, the Water-Cooled Lithium Lead (WCLL) DEMO breeding blanket line was selected in 1995 as one of the two EU lines to be developed in the next decade, in particular with the aim of manufacturing a Test Blanket Module (TBM) to be implemented in ITER. This specific goal has been maintained also in ITER-FEAT program even if the general design parameters of the TBMs have reported some changes. This paper is focused on the investigation of the WCLL-TBM nuclear response in ITER-FEAT through detailed 3D-Monte Carlo neutronic and photonic analyses. A 3D heterogeneous model of the most recent design of the WCLL-TBM has been set-up simulating reali…
On the nuclear response of the water-cooled Pb-17Li test blanket module for ITER-FEAT
2003
Abstract Within the European Fusion Technology Programme, the Water-Cooled Lithium Lead (WCLL) DEMO breeding blanket line was selected in 1995 as one of the two EU lines to be developed in the next decades, in particular with the aim of manufacturing a Test Blanket Module (TBM) to be tested in ITER-FEAT. The present paper is focused on the study of the WCLL-TBM nuclear response in ITER-FEAT, being specifically oriented to the investigation of the local effects due to the typical C-shaped tubes of the breeder zone, since they could play a pivotal role in the module-relevant thermo–mechanical design. A 3D heterogeneous model of the WCLL-TBM, realistically simulating its new lay out and taking…
Advanced Beam Dynamics Design for the Superconducting Heavy Ion Accelerator HELIAC
2019
The 10th International Particle Accelerator Conference, IPAC2019, Melbourne, Australia, 19 May 2019 - 24 May 2019; JACoW Publishing, Geneva, Switzerland 928-931 (2019). doi:10.18429/JACOW-IPAC2019-MOPTS034
First acceleration of heavy ion beams with a superconducting continuous wave HIM/GSI CW-linac
2020
Heavy Ion Accelerator Technology 2018, Lanzhou, China, 22 Oct 2018 - 26 Oct 2018; Journal of physics / Conference series 1401, 012012 (2020). doi:10.1088/1742-6596/1401/1/012012
Status and recent developments at the polarized-electron injector of the superconducting Darmstadt electron linear accelerator S-DALINAC
2011
At the superconducting Darmstadt electron linac a 100 keV source of polarized electrons has been installed. Major components had been tested prior to installation at an offline teststand. Commissioning of the new source at the S-DALINAC will take place early in 2011. We report on the performance of the teststand, simulations, developments on the laser systems, new radio-frequency components for the S-DALINAC injector, and the status of the implementation of the source.
Neutrino emission due to Cooper pairing of protons in cooling neutron stars: Collective effects
2000
The process of neutrino-pair radiation due to formation and breaking of Cooper pairs of protons in superconducting cores of neutron stars is considered with taking into account of the electromagnetic coupling of protons to ambient electrons. It is shown that plasma polarization strongly modifies the effective vector weak current of protons. Collective response of ambient electrons to the proton quantum transition contributes coherently to the complete interaction with the neutrino field and enhances the rate of neutrino-pair production by two orders of magnitude.