The SNO+ detector operated initially as a water Cherenkov detector. The
implementation of a sealed covergas system midway through water data taking
resulted in a significant reduction in the activity ...of $^{222}$Rn daughters in
the detector and allowed the lowest background to the solar electron scattering
signal above 5 MeV achieved to date. This paper reports an updated SNO+ water
phase $^8$B solar neutrino analysis with a total livetime of 282.4 days and an
analysis threshold of 3.5 MeV. The $^8$B solar neutrino flux is found to be
$\left(2.32^{+0.18}_{-0.17}\text{(stat.)}^{+0.07}_{-0.05}\text{(syst.)}\right)\times10^{6}$
cm$^{-2}$s$^{-1}$ assuming no neutrino oscillations, or
$\left(5.36^{+0.41}_{-0.39}\text{(stat.)}^{+0.17}_{-0.16}\text{(syst.)}
\right)\times10^{6}$ cm$^{-2}$s$^{-1}$ assuming standard neutrino oscillation
parameters, in good agreement with both previous measurements and Standard
Solar Model Calculations. The electron recoil spectrum is presented above 3.5
MeV.
The SNO+ collaboration reports its first spectral analysis of long-baseline
reactor antineutrino oscillation using 114 tonne-years of data. Fitting the
neutrino oscillation probability to the ...observed energy spectrum yields
constraints on the neutrino mass-squared difference $\Delta m^2_{21}$. In the
ranges allowed by previous measurements, the best-fit $\Delta m^2_{21}$ is
(8.85$^{+1.10}_{-1.33}$) $\times$ 10$^{-5}$ eV$^2$. This measurement is
continuing in the next phases of SNO+ and is expected to surpass the present
global precision on $\Delta m^2_{21}$ with about three years of data.
Using radiative Z
0→
τ
+τ
−γ
events collected with the OPAL detector at LEP at
s
=M
Z
during 1990–95, a direct study of the electromagnetic current at the
τγ vertex has been performed in terms of the ...anomalous magnetic form factor
F
2 of the
τ lepton. The analysis is based on a data sample of 1429
e
+e
−
→τ
+τ
−γ
events which are examined for a deviation from the expectation with
F
2=0. From the non-observation of anomalous
τ
+τ
−γ
production a limit of
−0.068<F
2<0.065
is obtained. This can also be interpreted as a limit on the electric dipole form factor
F
3 as
|eF
3|<3.7×10
−16
e
cm
.
The above ranges are valid at the 95% confidence level.
The SNO+ detector operated initially as a water Cherenkov detector. The implementation of a sealed covergas system midway through water data taking resulted in a significant reduction in the activity ...of \(^{222}\)Rn daughters in the detector and allowed the lowest background to the solar electron scattering signal above 5 MeV achieved to date. This paper reports an updated SNO+ water phase \(^8\)B solar neutrino analysis with a total livetime of 282.4 days and an analysis threshold of 3.5 MeV. The \(^8\)B solar neutrino flux is found to be \(\left(2.32^{+0.18}_{-0.17}\text{(stat.)}^{+0.07}_{-0.05}\text{(syst.)}\right)\times10^{6}\) cm\(^{-2}\)s\(^{-1}\) assuming no neutrino oscillations, or \(\left(5.36^{+0.41}_{-0.39}\text{(stat.)}^{+0.17}_{-0.16}\text{(syst.)} \right)\times10^{6}\) cm\(^{-2}\)s\(^{-1}\) assuming standard neutrino oscillation parameters, in good agreement with both previous measurements and Standard Solar Model Calculations. The electron recoil spectrum is presented above 3.5 MeV.
Gluon jets are identified in hadronic annihilation events by tagging two quark jets in the same hemisphere of an event. The gluon jet is defined inclusively as all the particles in the opposite ...hemisphere. Gluon jets defined in this manner have a close correspondence to gluon jets as they are defined for analytic calculations, and are almost independent of a jet finding algorithm. The charged particle multiplicity distribution of the gluon jets is presented, and is analyzed for its mean, dispersion, skew, and curtosis values, and for its factorial and cumulant moments. The results are compared to the analogous results found for a sample of light quark (uds) jets, also defined inclusively. We observe differences between the mean, skew and curtosis values of gluon and quark jets, but not between their dispersions. The cumulant moment results are compared to the predictions of QCD analytic calculations. A calculation which includes next-to-next-to-leading order corrections and energy conservation is observed to provide a much improved description of the data compared to a next-to-leading order calculation without energy conservation. There is agreement between the data and calculations for the ratios of the cumulant moments between gluon and quark jets.
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