L. Niedermeier

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We report the direct measurement of the 7Be solar neutrino signal rate performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The interaction rate of the 0.862 MeV 7Be neutrinos is 49+/-3stat+/-4syst counts/(day.100 ton). The hypothesis of no oscillation for 7Be solar neutrinos is inconsistent with our measurement at the 4sigma(More)
C. Arpesella, H.O. Back, M. Balata, T. Beau, G. Bellini, J. Benziger, S. Bonetti, A. Brigatti, C. Buck, B. Caccianiga, L. Cadonati, F. Calaprice, G. Cecchet, M. Chen, O. Dadoun, D. D’Angelo, A. De Bari, A. de Bellefon, E. De Haas, H. de Kerret, A. Derbin, M. Deutsch, A. Di Credico, F. Elisei, A. Etenko, F. von Feilitzsch, R. Fernholz, R. Ford, D. Franco, B.(More)
We calculate spin, charge, and azimuthal asymmetries in deeply virtual Compton scattering at leading twist-two level. The measurement of these asymmetries gives access to the imaginary and real part of all deeply virtual Compton scattering amplitudes. We note that a consistent description of this process requires taking into account twist-three(More)
Results of background measurements with a prototype of the Borexino detector were used to search for 478 keV solar axions emitted in the M1-transitions of 7 Li *. The Compton conversion of axion to a photon A + e → e + γ, axioelectric effect A + e + Z → e + Z, decay of axion in two photons A → 2γ and Primakoff conversion on nuclei A + Z → γ + Z are(More)
We present a general method for the solution of the renormalization group equations for the non-forward parton distributions on the two-loop level in the flavour singlet channel based on an orthogonal polynomial reconstruction. Using this formalism we study the effects of the evolution on recently proposed model distribution functions.
We study the amplitude of deeply virtual Compton scattering in next-to-leading order of perturbation theory including the two-loop evolution effects for different sets of skewed parton distributions (SPDs). It turns out that in the minimal subtraction scheme the relative radiative corrections are of order 20-50%. We analyze the dependence of our predictions(More)
Two-loop effects in the evolution of non-forward distributions. Abstract We study the effects of next-to-leading order corrections on the evolution of the twist-two non-forward parton distribution functions in the flavour non-singlet sector. It is found that the deviation from leading order evolution is small for all values of the parton momentum fraction(More)
We calculate spin, charge, and azimuthal asymmetries in deeply virtual Compton scattering at leading twist-two level. The measurement of these asymmetries gives access to the imaginary and real part of all deeply virtual Compton scattering amplitudes. We note that a consistent description of this process requires taking into account twist-three(More)
The Pauli exclusion principle (PEP) has been tested for nucleons (n, p) in 12 C and 16 O nuclei, using the results of background measurements with the prototype of the Borexino detector, the Counting Test Facility (CTF). The approach consisted of a search for γ, n, p and/or α's emitted in a non-Paulian transition of 1P-shell nucleons to the filled 1S 1/2(More)
We report on the study of a new liquid scintillator target for neutrino interactions in the framework of the research and development program of the Borexino solar neutrino experiment. The scintillator consists of 1,2–dimethyl–4–(1–phenylethyl)– benzene (phenyl–o–xylylethane, PXE) as solvent and 1,4-diphenylbenzene (paraTerphenyl, p-Tp) as primary and(More)