Precision measurement of the (7)Be solar neutrino interaction rate in Borexino

The rate of neutrino-electron elastic scattering interactions from 862 keV (7)Be solar neutrinos in Borexino is determined to be 46.0±1.5(stat)(-1.6)(+1.5)(syst)?counts/(day·100 ton). This corresponds to a ν(e)-equivalent (7)Be solar neutrino flux of (3.10±0.15)×10(9) cm(-2)?s(-1) and, under the assumption of ν(e) transition to other active neutrino flavours, yields an electron neutrino survival probability of 0.51±0.07 at 862 keV. The no flavor change hypothesis is ruled out at 5.0?σ. A global solar neutrino analysis with free fluxes determines Φ(pp)=6.06(-0.06)(+0.02)×10(10) cm(-2)?s(-1) and Φ(CNO)<1.3×10(9) cm(-2)?s(-1) (95% C.L.). These results significantly improve the precision with which the Mikheyev-Smirnov-Wolfenstein large mixing angle neutrino oscillation model is experimentally tested at low energy.     

LETTER: Warm Inflation: Towards a Realistic COBE Data Power Spectrum for Matter and Metric Thermal Coupled Fluctuations

I consider the COBE data coarse–grained field that characterize the now observable universe for a model of warm inflation which takes into account the thermally coupled fluctuations of the scalar field with the thermal bath. The power spectrum for both, matter and metric fluctuations are analyzed. I find that the amplitude for the fluctuations of the metric during the horizon entry should be very small for the expected values of temperature.     

The forward search interactive outlier detection in cointegrated VAR analysis

Cointegration analysis is particularly sensitive to outlying observations. Traditional robust approaches rely on parameter estimates based on weighting schemes to penalize aberrant units. This, in particular, is the idea underlying pseudo maximum likelihood robust estimators. Atypical observations, however, can reveal useful information about the investigated phenomenon. Aiming to detect these observations, we extend the forward search procedure to the cointegrated vector autoregressive model. The analysis is carried out by building up subsets of increasing dimension and monitoring suitable statistics at each subset size. Simulation experiments and real data analysis highlight that our forward search is more effective than the pseudo maximum likelihood in detecting atypical units and data structures.     

Measurement of beam-recoil observables Ox , Oz and target asymmetry T for the reaction \gammap → K+ \Lambda

The double polarization (beam-recoil) observables $\ensuremath O_x$ and $\ensuremath O_z$ have been measured for the reaction $ \gamma$ p → K ⁺ $ \Lambda$ from threshold production to $\ensuremath E_{\gamma} \sim 1500$ MeV. The data were obtained with the linearly polarized beam of the GRAAL facility. Values for the target asymmetry T could also be extracted despite the use of an unpolarized target. Analyses of our results by two isobar models tend to confirm the necessity to include new or poorly known resonances in the 1900MeV mass region.     

Search for an enhanced production of low energy pions in C(p, π+)X,Cu(p, π+)X,and Cu(p, π∘)X reactions for 300 MeV≦Tp≦400 MeV

The observation of an enhancement in the production of low energy pions in the Cu(p, ⁺)X reaction is confirmed. The width of the bump is about 5 MeV around 350 MeV. A similar enhancement appears at 330 MeV for C(p, ⁺)X but the width has not been measured. An attempt to observe this behaviour in Cu(p, )X is described. From the data one cannot conclude about the existence of a structure around 350 MeV proton energy. The lack of resolution in the spectrometer may have washed out the small effect expected from ⁺ measurements.