7,584 research outputs found
Human casualties and agricultural crop raiding by wild pigs and mitigation strategies in India
Chauhan, N.P.S
Agricultural crop depredation by nilgai antelope (Boselaphus tragocamelus) and mitigation strategies: challenges in India
Chauhan, N.P.S
Perturbativity constraints on and left-right models and implications for heavy gauge boson searches
We derive perturbativity constraints on beyond standard model scenarios with
extra gauge groups, such as or , whose generators contribute to
the electric charge, and show that there are both upper and lower limits on the
additional gauge couplings, from the requirement that the couplings remain
perturbative up to the grand unification theory (GUT) scale. This leads to
stringent constraints on the masses of the corresponding gauge bosons and their
collider phenomenology. We specifically focus on the models based on
and the left-right symmetric
models based on , and discuss the
implications of the perturbativity constraints for new gauge boson searches at
current and future colliders. In particular, we find that the stringent flavor
constraints in the scalar sector of left-right model set a lower bound on the
right-handed scale TeV, if all the gauge and quartic couplings
are to remain perturbative up to the GUT scale. This precludes the prospects of
finding the boson in the left-right model at the LHC, even in the
high-luminosity phase, and leaves only a narrow window for the boson. A
much broader allowed parameter space, with the right-handed scale up to
TeV, could be probed at the future 100 TeV collider.Comment: 30 pages, 9 figures, 4 tables, minor changes, version to be published
in JHE
() spectroscopy using Cornell potential
The mass spectra and decay properties of heavy quarkonia are computed in
nonrelativistic quark-antiquark Cornell potential model. We have employed the
numerical solution of Schr\"odinger equation to obtain their mass spectra using
only four parameters namely quark mass (, ) and confinement strength
(, ). The spin hyperfine, spin-orbit and tensor
components of the one gluon exchange interaction are computed perturbatively to
determine the mass spectra of excited , , and states. Digamma,
digluon and dilepton decays of these mesons are computed using the model
parameters and numerical wave functions. The predicted spectroscopy and decay
properties for quarkonia are found to be consistent with available experimental
observations and results from other theoretical models. We also compute mass
spectra and life time of the meson without additional parameters. The
computed electromagnetic transition widths of heavy quarkonia and mesons
are in tune with available experimental data and other theoretical approaches
Predictions from non trivial Quark-Lepton complementarity
The complementarity between the quark and lepton mixing matrices is shown to
provide robust predictions. We obtain these predictions by first showing that
the matrix V_M, product of the quark (CKM) and lepton (PMNS) mixing matrices,
may have a zero (1,3) entry which is favored by experimental data.
We obtain that any theoretical model with a vanishing (1,3) entry of V_M that
is in agreement with quark data, solar, and atmospheric mixing angle leads to
. This value is consistent with the
present 90% CL experimental upper limit. We also investigate the prediction on
the lepton phases. We show that the actual evidence, under the only assumption
that the correlation matrix V_M product of CKM and PMNS has a zero in the entry
(1,3), gives us a prediction for the three CP-violating invariants J, S_1, and
S_2. A better determination of the lepton mixing angles will give stronger
prediction for the CP-violating invariants in the lepton sector. These will be
tested in the next generation experiments. Finally we compute the effect of non
diagonal neutrino mass in "l_i -> l_j gamma" in SUSY theories with non trivial
Quark-Lepton complementarity and a flavor symmetry. The Quark-Lepton
complementarity and the flavor symmetry strongly constrain the theory and we
obtain a clear prediction for the contribution to "mu -> e gamma" and the "tau"
decays "tau -> e gamma" and "tau -> mu gamma". If the Dirac neutrino Yukawa
couplings are degenerate but the low energy neutrino masses are not degenerate,
then the lepton decays are related among them by the V_M entries. On the other
hand, if the Dirac neutrino Yukawa couplings are hierarchical or the low energy
neutrino masses are degenerate, then the prediction for the lepton decays comes
from the CKM hierarchy.Comment: 15 pages, 5 figures, ws-ijmpa class included, Proceedings of the CTP
Symposium on Sypersymmetry at LH
Two Gallium data sets, spin flavour precession and KamLAND
We reexamine the possibility of a time modulation of the low energy solar
neutrino flux which is suggested by the average decrease of the Ga data in line
with our previous arguments. We perform two separate fits to the solar neutrino
data, one corresponding to 'high' and the other to 'low' Ga data, associated
with low and high solar activity respectively. We therefore consider an
alternative to the conventional solar+KamLAND fitting, which allows one to
explore the much wider range of the angle permitted by the
KamLAND fitting alone. We find a solution with parameters in which the 'high' and
the 'low' Ga rates lie far apart and are close to their central values and is
of comparable quality to the global best fit, where these rates lie much closer
to each other. This is an indication that the best fit in which all solar and
KamLAND data are used is not a good measure of the separation of the two Ga
data sets, as the information from the low energy neutrino modulation is
dissimulated in the wealth of data. Furthermore for the parameter set proposed
one obtains an equally good fit to the KamLAND energy spectrum and an even
better fit than the 'conventional' LMA one for the reactor antineutrino
survival probability as measured by KamLAND.Comment: V2: 15 pages, 3 eps figures, fit improved, final version to appear in
Journal of Physics
Dynamic Characteristics of Aerosol Optical Properties over Dibrugarh City in the North-Eastern Indian Region during 2018–2021
Aerosols play an important role in the earth\u27s environment across the globe through their involvement in various earth system cycles. The change in the aerosol properties may cause short and long-term impacts, the knowledge of such changes is useful in the estimation of the pollution sources of any region. We have carried out the analysis of the aerosols\u27 optical and radiative properties using AERONET station data from 2018 to 2021 in Dibrugarh City. The higher Aerosol Optical Depth (AOD) values during winter and pre-monsoon months indicate high anthropogenic activities, and biomass burning in Dibrugarh. The impact of various sources and daily meteorological parameters help in understanding the diurnal variations of the AOD, Ångström Exponent (AE), and column water (CW). Fine aerosol fractions dominate the aerosol volume, but sometimes the long-range transport of dust affects aerosol properties during pre-monsoon months (MAM). MODIS-derived AOD and AERONET AOD values show a good correlation, with R2 = 0.68. The highest volume of the aerosols reaches up to 0.11 µm3 µm–2 during pre-monsoon months, whereas it lies below 0.05 µm3 µm–2 in other seasons. SSA values indicate the presence of scattering aerosols but in 2020, a sudden decline in the SSA values shows a strong rise in the absorbing aerosols. Throughout the study period (2018–2021), the positive radiative forcing indicates a rise in atmospheric heating
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