اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدAtmospheric neutrinos in ice and measurement of neutrino oscillation parameters
144
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
The main goal of the IceCube Deep Core Array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show that the very high statistics atmospheric neutrino data can be used to obtain precise measurements of the main oscillation parameters.
قيم البحث
اقرأ أيضاً
The India-based Neutrino Observatory (INO) will host a 50 kt magnetized iron calorimeter (ICAL@INO) for the study of atmospheric neutrinos. Using the detector resolutions and efficiencies obtained by the INO collaboration from a full-detector GEANT4-
based simulation, we determine the reach of this experiment for the measurement of the atmospheric neutrino mixing parameters ($sin^2 theta_{23}$ and $|Delta m_{32}^2 |$). We also explore the sensitivity of this experiment to the deviation of $theta_{23}$ from maximal mixing, and its octant.
The main goal of the IceCube Deep Core Array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show here that cascade measurements in the Ice Cube Deep Core Array
can provide strong evidence for tau neutrino appearance in atmospheric neutrino oscillations. A careful study of these tau neutrinos is crucial, since they constitute an irreducible background for astrophysical neutrino detection.
We show that the measurements of 10 GeV atmospheric neutrinos by an upcoming array of densely packed phototubes buried deep inside the IceCube detector at the South Pole can be used to determine the neutrino mass hierarchy for values of sin^2(2theta1
3) close to the present bound, if the hierarchy is normal. These results are obtained for an exposure of 100 Mton years and systematic uncertainties up to 10%.
The NOvA experiment has made a $4.4sigma$-significant observation of $bar u_{e}$ appearance in a 2 GeV $bar u_{mu}$ beam at a distance of 810 km. Using $12.33times10^{20}$ protons on target delivered to the Fermilab NuMI neutrino beamline, the experi
ment recorded 27 $bar u_{mu} rightarrow bar u_{e}$ candidates with a background of 10.3 and 102 $bar u_{mu} rightarrow bar u_{mu}$ candidates. This new antineutrino data is combined with neutrino data to measure the oscillation parameters $|Delta m^2_{32}| = 2.48^{+0.11}_{-0.06}times10^{-3}$ eV$^2/c^4$, $sin^2 theta_{23} = 0.56^{+0.04}_{-0.03}$ in the normal neutrino mass hierarchy and upper octant and excludes most values near $delta_{rm CP}=pi/2$ for the inverted mass hierarchy by more than 3$sigma$. The data favor the normal neutrino mass hierarchy by 1.9$sigma$ and $theta_{23}$ values in the upper octant by 1.6$sigma$.
The standard three-neutrino (3nu) oscillation framework is being increasingly refined by results coming from different sets of experiments, using neutrinos from solar, atmospheric, accelerator and reactor sources. At present, each of the known oscill
ation parameters [the two squared mass gaps (delta m^2, Delta m^2) and the three mixing angles (theta_12}, theta_13, theta_23)] is dominantly determined by a single class of experiments. Conversely, the unknown parameters [the mass hierarchy, the theta_23 octant and the CP-violating phase delta] can be currently constrained only through a combined analysis of various (eventually all) classes of experiments. In the light of recent new results coming from reactor and accelerator experiments, and of their interplay with solar and atmospheric data, we update the estimated N-sigma ranges of the known 3nu parameters, and revisit the status of the unknown ones. Concerning the hierarchy, no significant difference emerges between normal and inverted mass ordering. A slight overall preference is found for theta_23 in the first octant and for nonzero CP violation with sin delta < 0; however, for both parameters, such preference exceeds 1 sigma only for normal hierarchy. We also discuss the correlations and stability of the oscillation parameters within different combinations of data sets.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
