Measurement of CNGS muon neutrino speed with Borexino

We have measured the speed of muon neutrinos with the Borexino detector using short-bunch CNGS beams. The final result for the difference in time-of-flight between a =17 GeV muon neutrino and a particle moving at the speed of light in vacuum is {\delta}t = 0.8 \pm 0.7stat \pm 2.9sys ns, well consistent with zero.Comment: 6 pages, 5 figure

Measurement of the nuclear multiplicity ratio for Ks0K^0_s hadronization at CLAS

The influence of cold nuclear matter on lepto-production of hadrons in semi-inclusive deep inelastic scattering is measured using the CLAS detector in Hall B at Jefferson Lab and a 5.014 GeV electron beam. We report the $K_s^0$ multiplicity ratios for targets of C, Fe, and Pb relative to deuterium as a function of the fractional virtual photon energy $z$ transferred to the $K_s^0$ and the transverse momentum squared $p_{T}^2$ of the $K_s^0$. We find that the multiplicity ratios for $K^0_s$ are reduced in the nuclear medium at high $z$ and low $p_{T}^2$, with a trend for the $K^0_s$ transverse momentum to be broadened in the nucleus for large $p_{T}^2$.Comment: Submitted to Phys. Lett.

Precise Measurements of Beam Spin Asymmetries in Semi-Inclusive π0\pi^0 production

We present studies of single-spin asymmetries for neutral pion electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV polarized electrons from an unpolarized hydrogen target, using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. A substantial $\sin \phi_h$ amplitude has been measured in the distribution of the cross section asymmetry as a function of the azimuthal angle $\phi_h$ of the produced neutral pion. The dependence of this amplitude on Bjorken $x$ and on the pion transverse momentum is extracted with significantly higher precision than previous data and is compared to model calculations.Comment: to be submitted PL

Absence of day-night asymmetry of 862 keV Be-7 solar neutrino rate in Borexino and MSW oscillation parameters

We report on a search for the day-night asymmetry of the Be-7 solar neutrino rate measured by Borexino at the Laboratori Nazionali del Gran Sasso (LNGS), Italy. The measured value, Adn=0.001 +- 0.012 (stat) +- 0.007 (syst), shows the absence of a significant asymmetry. This result alone rejects the so-called LOW solution at more than 8.5 sigma. Combined with the other solar neutrino data, it isolates the Large Mixing Angle (LMA) -- MSW solution at DeltaChi2 > 190 without relying on the assumption of CPT symmetry in the neutrino sector. We also show that including the day-night asymmetry, data from Borexino alone restricts the MSW neutrino oscillations to the LMA solution at 90% confidence level.Comment: 5 figures, published on Phys. Lett

Evidence for the Onset of Color Transparency in ρ0\rho^0 Electroproduction off Nuclei

We have measured the nuclear transparency of the incoherent diffractive $A(e,e'\rho^0)$ process in $^{12}$C and $^{56}$Fe targets relative to $^2$H using a 5 GeV electron beam. The nuclear transparency, the ratio of the produced $\rho^0$'s on a nucleus relative to deuterium, which is sensitive to $\rho A$ interaction, was studied as function of the coherence length ($l_c$), a lifetime of the hadronic fluctuation of the virtual photon, and the four-momentum transfer squared ($Q^2$). While the transparency for both $^{12}$C and $^{56}$Fe showed no $l_c$ dependence, a significant $Q^2$ dependence was measured, which is consistent with calculations that included the color transparency effects.Comment: 6 pages and 4 figure

Borexino: recent results, detector calibration and future perspectives

none89Marco Pallavicini;G. Bellini;J. Benziger;S. Bonetti;M. Buizza Avanzini;B. Caccianiga;L. Cadonati;F. Calaprice;C. Carraro;A. Chavarria;F. Dalnoki-Veress;D. DʼAngelo;S. Davini;H. de Kerret;A. Derbin;A. Etenko;F. von Feilitzsch;K. Fomenko;D. Franco;C. Galbiati;S. Gazzana;C. Ghiano;M. Giammarchi;M. Goeger-Neff;A. Goretti;E. Guardincerri;S. Hardy;Aldo Ianni;Andrea Ianni;M. Joyce;V. Kobychev;Y. Koshio;G. Korga;D. Kryn;M. Laubenstein;M. Leung;T. Lewke;E. Litvinovich;B. Loer;F. Lombardi;P. Lombardi;L. Ludhova;I. Machulin;S. Manecki;W. Maneschg;G. Manuzio;Q. Meindl;E. Meroni;L. Miramonti;M. Misiaszek;D. Montanari;V. Muratova;L. Oberauer;M. Obolensky;F. Ortica;M. Pallavicini;L. Papp;L. Perasso;S. Perasso;A. Pocar;R.S. Raghavan;G. Ranucci;A. Razeto;A. Re;P. Risso;A. Romani;D. Rountree;A. Sabelnikov;R. Saldanha;C. Salvo;S. Schönert;H. Simgen;M. Skorokhvatov;O. Smirnov;A. Sotnikov;S. Sukhotin;Y. Suvorov;R. Tartaglia;G. Testera;D. Vignaud;R.B. Vogelaar;J. Winter;M. Wojcik;M. Wurm;A. Wright;J. Xu;O. Zaimidoroga;S. Zavatarelli;G. ZuzelPallavicini, Marco; G., Bellini; J., Benziger; S., Bonetti; M., Buizza Avanzini; B., Caccianiga; L., Cadonati; F., Calaprice; Carraro, Carlo; A., Chavarria; F., Dalnoki Veress; D., Dʼangelo; S., Davini; H., de Kerret; A., Derbin; A., Etenko; F., von Feilitzsch; K., Fomenko; D., Franco; C., Galbiati; S., Gazzana; C., Ghiano; M., Giammarchi; M., Goeger Neff; A., Goretti; E., Guardincerri; S., Hardy; Aldo, Ianni; Andrea, Ianni; M., Joyce; V., Kobychev; Y., Koshio; G., Korga; D., Kryn; M., Laubenstein; M., Leung; T., Lewke; E., Litvinovich; B., Loer; F., Lombardi; P., Lombardi; L., Ludhova; I., Machulin; S., Manecki; W., Maneschg; Manuzio, Giulio; Q., Meindl; E., Meroni; L., Miramonti; M., Misiaszek; D., Montanari; V., Muratova; L., Oberauer; M., Obolensky; F., Ortica; M., Pallavicini; L., Papp; L., Perasso; S., Perasso; A., Pocar; R. S., Raghavan; G., Ranucci; A., Razeto; A., Re; P., Risso; A., Romani; D., Rountree; A., Sabelnikov; R., Saldanha; C., Salvo; S., Schönert; H., Simgen; M., Skorokhvatov; O., Smirnov; A., Sotnikov; S., Sukhotin; Y., Suvorov; R., Tartaglia; G., Testera; D., Vignaud; R. B., Vogelaar; J., Winter; M., Wojcik; M., Wurm; A., Wright; J., Xu; O., Zaimidoroga; S., Zavatarelli; G., Zuze

Neutrinos from the sun and from radioactive sources

none90A. Ianni;G. Bellini;J. Benziger;D. Bick;G. Bonfini;D. Bravo;M. Buizza Avanzini;B. Caccianiga;L. Cadonati;F. Calaprice;C. Carraro;P. Cavalcante;A. Chavarria;D. DʼAngelo;S. Davini;A. Derbin;A. Etenko;D. Franco;K. Fomenko;C. Galbiati;S. Gazzana;C. Ghiano;M. Giammarchi;M. Göger-Neff;A. Goretti;L. Grandi;E. Guardincerri;S. Hardy;Andrea Ianni;A. Kayunov;V. Kobychev;D. Korablev;G. Korga;Y. Koshio;D. Kryn;M. Laubenstein;T. Lewke;E. Litvinovich;L. Ludhova;B. Loer;F. Lombardi;P. Lombardi;I. Machulin;S. Manecki;W. Maneschg;G. Manuzio;Q. Meindl;E. Meroni;L. Miramonti;M. Misiaszek;D. Montanari;P. Mosteiro;V. Muratova;L. Oberauer;M. Obolensky;F. Ortica;K. Otis;M. Pallavicini;L. Papp;L. Perasso;S. Perasso;A. Pocar;R.S. Raghavan;G. Ranucci;A. Razeto;A. Re;P.A. Romani;A. Sabelnikov;R. Saldanha;C. Salvo;S. Schönert;H. Simgen;M. Skorokhvatov;O. Smirnov;A. Sotnikov;S. Sukhotin;Y. Suvorov;R. Tartaglia;G. Testera;D. Vignaud;R.B. Vogelaar;F. Von Feilitzsch;J. Winter;M. Wojcik;A. Wright;M. Wurm;J. Xu;O. Zaimidoroga;S. Zavatarelli;G. ZuzelA., Ianni; G., Bellini; J., Benziger; D., Bick; G., Bonfini; D., Bravo; M., Buizza Avanzini; B., Caccianiga; L., Cadonati; F., Calaprice; Carraro, Carlo; P., Cavalcante; A., Chavarria; D., Dʼangelo; Davini, Stefano; A., Derbin; A., Etenko; D., Franco; K., Fomenko; C., Galbiati; S., Gazzana; C., Ghiano; M., Giammarchi; M., Göger Neff; A., Goretti; L., Grandi; E., Guardincerri; S., Hardy; Andrea, Ianni; A., Kayunov; V., Kobychev; D., Korablev; G., Korga; Y., Koshio; D., Kryn; M., Laubenstein; T., Lewke; E., Litvinovich; L., Ludhova; B., Loer; F., Lombardi; P., Lombardi; I., Machulin; S., Manecki; W., Maneschg; Manuzio, Giulio; Q., Meindl; E., Meroni; L., Miramonti; M., Misiaszek; D., Montanari; P., Mosteiro; V., Muratova; L., Oberauer; M., Obolensky; F., Ortica; K., Otis; Pallavicini, Marco; L., Papp; L., Perasso; S., Perasso; A., Pocar; R. S., Raghavan; G., Ranucci; A., Razeto; A., Re; P. A., Romani; A., Sabelnikov; R., Saldanha; C., Salvo; S., Schönert; H., Simgen; M., Skorokhvatov; O., Smirnov; A., Sotnikov; S., Sukhotin; Y., Suvorov; R., Tartaglia; G., Testera; D., Vignaud; R. B., Vogelaar; F., Von Feilitzsch; J., Winter; M., Wojcik; A., Wright; M., Wurm; J., Xu; O., Zaimidoroga; S., Zavatarelli; G., Zuze