1,207 research outputs found
Neutrinos from Stellar Collapse: Comparison of signatures in water and heavy water detectors
Signatures of neutrino and antineutrino signals from stellar collapse in
heavy water detectors are contrasted with those in water detectors. The effects
of mixing, especially due to the highly dense matter in the supernova core, are
studied. The mixing parameters used are those sets allowed by current
understanding of available neutrino data: from solar, atmospheric and
laboratory neutrino experiments. Signals at a heavy water detector, especially
the dominant charged current reactions on deuteron, are very sensitive to some
of these sets of allowed mixing parameters. Theoretical uncertainties on
supernova neutrino spectra notwithstanding, a combination of supernova
measurements with water and heavy water detectors may be able to distinguish
many of these mixing possibilities and thus help in ruling out many of them.Comment: 36 pages Latex file, with 13 postscript figures; important
improvements in the analysis and more detailed presentation of results. To
appear in Phys. Rev.
Innovative Teaching and Learning
The biggest challenge any teacher faces is capturing the students’ attention, and putting across ideas in such a way that it stays with them long after they have left the classroom. For this to happen, classroom experience should be redefined and innovative ideas that make teaching learning methods more effective should be implemented. So here are some innovative ideas that will help teachers reinvent their teaching methods and make their classes interesting. The use of innovative methods in educational institutions has the potential not only to improve education, but also to empower people, strengthen governance and galvanize the effort to achieve the human development goal for the country. The purpose of this paper is to suggest useful innovative teaching methods which could easily be imparted knowledge to the students
Neutrino oscillation probabilities: Sensitivity to parameters
We study in detail the sensitivity of neutrino oscillation probabilities to
the fundamental neutrino parameters and their possible determination through
experiments. The first part of the paper is devoted to the broad theme of
isolating regions in the neutrino (and anti-neutrino) energy and propagation
length that are sensitive to the oscillation parameters. Such a study is
relevant to neutrinos both from the Earth's atmosphere or from a neutrino
factory. For completeness we discuss the sensitivity, however small, to the
parameters involved in a three-generation framework, and to the Earth matter
density profile. We then study processes relevant to atmospheric neutrinos
which are sensitive to and allow precision measurements of the mixing angle
theta_23 and mass-squared difference delta_32 apart from the mixing angle
theta_13. Crucial to this analysis is charge identification; detectors having
this capability can isolate these matter effects. In particular, we address the
issue of using matter effects to determine whether the mixing angle theta_23 is
maximal, and, if not, to explore how well its octant can be determined. When
realistic detector resolutions are included, we find that deviations of about
15% (20%) from a maximal value of sin^2 theta_23=1/2 can be measured at 95%
(99%) CL provided theta_13 is non-zero, sin^2 theta_13 >= 0.015, and the
neutrino mass ordering is normal, with fairly large exposures of 1000
kton-years.Comment: 37 pages Latex file, 30 eps figure files; minor typos fixe
TDMA- MAC Protocol based Energy- Potency for Periodic Sensing Applications in Wireless sensing Networks
Energy potency could be a major demand in wireless sensing element networks. Media Access management is one in every of the key areas wherever energy potency is achieved by planning such MAC protocol that's tuned to the necessities of the sensing element networks. Applications have different necessities and one MAC protocol can't be best TDMA-based MAC (TDMAC) protocol that is specially designed for such applications that need periodic sensing of the sensing element field. TDMAC organizes nodes into clusters. Nodes send their knowledge to their cluster head (CH) and CHs forward it to the bottom station. CHs removed from the bottom station use multi-hop communication by forwarding their knowledge to CHs nearer than themselves to the bottom station each put down-cluster and intra-cluster communication is only TDMA-based that effectively eliminates each inter cluster further as intra-cluster interference
Probing optically silent superfluid stripes in cuprates
Unconventional superconductivity in the cuprates emerges from, or coexists
with, other types of electronic order. However, these orders are sometimes
invisible because of their symmetry. For example, the possible existence of
superfluid charge stripes in the normal state of single layer cuprates cannot
be validated with infrared optics, because interlayer tunneling fluctuations
vanish on average. Similarly, it is not easy to establish if charge orders are
responsible for dynamical decoupling of the superconducting layers over broad
ranges of doping and temperatures. Here, we show that TeraHertz pulses can
excite nonlinear tunneling currents between linearly de-coupled charge-ordered
planes. A giant TeraHertz third harmonic signal is observed in
La1.885Ba0.115CuO4 far above Tc=13 K and up to the charge ordering temperature
TCO = 55 K. We model these results by considering large order-parameter-phase
oscillations in a pair density wave condensate, and show how nonlinear mixing
of optically silent tunneling modes can drive large dipole-carrying
super-current oscillations. Our results provide compelling experimental support
for the presence of hidden superfluid order in the normal state of cuprates.
These experiments also underscore the power of nonlinear TeraHertz optics as a
sensitive probe of frustrated excitations in quantum solids.Comment: 9 pages main text, 5 figures, 12 page supplementar
Group velocity of neutrino waves
We follow up on the analysis of Mecozzi and Bellini (arXiv:1110:1253v1) where
they showed, in principle, the possibility of superluminal propagation of
neutrinos, as indicated by the recent OPERA result. We refine the analysis by
introducing wave packets for the superposition of energy eigenstates and
discuss the implications of their results with realistic values for the mixing
and mass parameters in a full three neutrino mixing scenario. Our analysis
shows the possibility of superluminal propagation of neutrino flavour in a very
narrow range of neutrino parameter space. Simultaneously this reduces the
number of observable events drastically. Therefore, the OPERA result cannot be
explained in this frame-work.Comment: 10 pages revtex with 2 figures. Important changes have been made; in
particular, it has been revised to include a discussion on the nature of the
measurement and its impact on the resul
Reunion of Vicious Walkers: Results from -Expansion -
The anomalous exponent, , for the decay of the reunion probability
of vicious walkers, each of length , in dimensions,
is shown to come from the multiplicative renormalization constant of a
directed polymer partition function. Using renormalization group(RG) we
evaluate to . The survival probability exponent is
. For , our RG is exact and stops at .
For , the log corrections are also determined. The number of walkers that
are sure to reunite is 2 and has no expansion.Comment: No of pages: 11, 1figure on request, Revtex3,IP/BBSR/929
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