2,575 research outputs found
Prospects of measuring the leptonic CP phase with atmospheric neutrinos
We have studied the prospects of measuring the CP violating phase with
atmospheric neutrinos at a large magnetized iron calorimeter detector
considering the muons (directly measurable) of the neutrino events generated by
a MonteCarlo event generator Nuance. The effect of and
appears dominantly neither in atmospheric neutrino oscillation
nor in solar neutrino oscillation, but appears as subleading in both cases.
These are observable in range of GeV for atmospheric neutrino, where
solar and atmospheric oscillation couple. In this regime, the quasi-elastic
events dominate and the energy resolution is very good, but the angular
resolution is very poor. Unlike beam experiments this poor angular resolution
acts against its measurements. However, we find that one can be able to
distinguish and at 90% confidence
level. We find no significant sensitivity for or
.Comment: 9 pages, 7 figures, clarifying discussions on results added; accepted
in Phys. Rev.
Kodaikanal Digitized White-light Data Archive (1921-2011): Analysis of various solar cycle features
Long-term sunspot observations are key to understand and predict the solar
activities and its effects on the space weather.Consistent observations which
are crucial for long-term variations studies,are generally not available due to
upgradation/modifications of observatories over the course of time. We present
the data for a period of 90 years acquired from persistent observation at the
Kodaikanal observatory in India. We use an advanced semi-automated algorithm to
detect the sunspots form each calibrated white-light image. Area, longitude and
latitude of each of the detected sunspots are derived. Implementation of a
semi-automated method is very necessary in such studies as it minimizes the
human bias in the detection procedure. Daily, monthly and yearly sunspot area
variations obtained from the Kodaikanal, compared well with the Greenwich
sunspot area data. We find an exponentially decaying distribution for the
individual sunspot area for each of the solar cycles. Analyzing the histograms
of the latitudinal distribution of the detected sunspots, we find Gaussian
distributions, in both the hemispheres, with the centers at 15
latitude. The height of the Gaussian distributions are different for the two
hemispheres for a particular cycle. Using our data, we show clear presence of
Waldmeier effect which correlates the rise time with the cycle amplitude. Using
the wavelet analysis, we explored different periodicities of different time
scales present in the sunspot area times series.Comment: Accepted for Publication in A&
A scaling theory of quantum breakdown in solids
We propose a new scaling theory for general quantum breakdown phenomena. We
show, taking Landau-Zener type breakdown as a particular example, that the
breakdown phenomena can be viewed as a quantum phase transition for which the
scaling theory is developed. The application of this new scaling theory to
Zener type breakdown in Anderson insulators, and quantum quenching has been
discussed.Comment: 3 page
- …