5,754 research outputs found
New Formulas and Predictions for Running Fermion Masses at Higher Scales in SM, 2HDM, and MSSM
Including contributions of scale-dependent vacuum expectation values, we
derive new analytic formulas and obtain substantially different numerical
predictions for the running masses of quarks and charged-leptons at higher
scales in the SM, 2HDM and MSSM. These formulas exhibit significantly different
behaviours with respect to their dependence on gauge and Yukawa couplings than
those derived earlier. At one-loop level the masses of the first two
generations are found to be independent of Yukawa couplings of the third
generation in all the three effective theories in the small mixing limit.
Analytic formulas are also obtained for running in 2HDM and
MSSM. Other numerical analyses include study of the third generation masses at
high scales as functions of low-energy values of and SUSY scale
GeV.Comment: 42 pages RevTeX, including 16 figures. Typos corrected and one
reference adde
Vanishing corrections on the intermediate scale and implications for unification of forces
In two-step breaking of a class of grand unified theories including SO(10),we
prove a theorem showing that the scale where the Pati-Salam gauge
symmetry with parity breaks down to the standard gauge group,has vanishing
corrections due to all sources emerging from higher scales such as
the one-loop and all higher loop effects,the GUT-threshold,gravitational
smearing,and string threshold effects. Implications of such a scale for the
unification of gauge couplings with small Majorana neutrino masses are
discussed.In string inspired SO(10) we show that ,needed for neutrino masses,with the GUT scale can
be realized provided certain particle states in the predicted spectum are
light.Comment: 21 pages, Late
Precision and uncertainties in mass scale predictions in SUSY SO(10) with SU(2)_L x SU(2)_R x U(1)_{B-L} x SU(3)_C intermediate breaking
In a class of SUSY SO(10) with
intermediate gauge symmetry, we observe that the
prediction on the unification mass is unaffected by
Planck-scale-induced gravitational and intermediate-scale-threshold effects,
although the intermediate scale itself is subject to such corrections.
In particular, without invoking the presence of additional lighter scalar
degrees of freedom but including plausible and reasonable threshold effects, we
find that interesting solutions for neutrino physics corresponding to
GeV and GeV are
permitted in the minimal models. Possibilities of low-mass right-handed gauge
bosons corresponding to TeV consistent with the CERN-LEP data
are pointed out in a number of models when threshold effects are included using
effective mass parameters.Comment: 12 pages including 7 tables (Typos corrected as per the published
version
Offline e-cash system
The e-cash scheme and the digital content transactions are the need of the hour. In the coming years, all these digital transactions will grow tremendously. So, a secure e-cash scheme is of utmost requirement. e-cash scheme, which is untraceable and maintains the security features, make it possible for the customers and the merchants to exchange the e-cash and the merchandise with privacy. So, there is a need to design an e-cash scheme with strong cryptosystem and algorithms in order to facilitate efficient digital transactions. There are two types of e-cash systems: Offine e-cash systems and online e-cash systems. Offine e-cash systems make it possible for the customer to pay the e-coin to the merchant without any involvement of bank. In online schemes, we require the involvement of the bank. The two most fundamental security features associated with offine scheme is the anonymity and the double spending detection. The proposed scheme maintains both the above features along with unforgeability. Besides, the E-coins have their expiration date so that the bank faces no hassles and can manage its database efficiently. This feature also ensures portability as the coins can be transferred to storage devices through the networks
Threshold Effects on Quasi-degenerate Neutrinos with High-scale Mixing Unification
We consider threshold effects on neutrino masses and mixings in a recently
proposed model for understanding large solar and atmospheric mixing angles
using radiative magnification for the case of quasi-degenerate neutrinos. We
show that the magnitude of the threshold effects is sufficient to bring
concordance between the predictions of this model and latest data from and on observations of neutrino oscillations.Comment: Four pages, no figure
Intermediate left-right gauge symmetry, unification of couplings and fermion masses in SUSY
If left-right gauge theory occurs as an intermediate symmetry in a GUT then,
apart from other advantages, it is possible to obtain the see-saw scale
necessary to understand small neutrino masses with Majorana coupling of order
unity. Barring threshold or non-renormalizable gravitational effects, or
assumed presence of additional light scalar particles of unprescribed origin,
all other attempts to achieve manifest one-loop gauge coupling unification in
SUSY SO(10) with left-right intermediate symmetry have not been successful so
far. Attributing this failure to lack of flavor symmetry in the GUT, we show
how the spontaneous symmetry breaking of leads to such
intermediate scale extending over a wide range, GeV
to GeV. All the charged fermion masses are fitted at the see-saw
scale, GeV which is obtained with
Majorana coupling . Using a constrained parametrization in which
CP-violation originates only from quark sector, besides other predictions made
in the neutrino sector, the reactor mixing angle is found to be which is in the range accessible to ongoing and
planned experiments. The leptonic Dirac phase turns out to be radians with Jarlskog invariant .Comment: Minor clarification and few references added to match the published
versio
Radiative stability of neutrino-mass textures
Neutrino-mass textures proposed at high-scales are known to be unstable
against radiative corrections especially for nearly degenerate eigen values.
Within the renormalization group constraints we find a mechanism in a class of
gauge theories which guarantees reproduction of any high-scale texture at low
energies with radiative stability. We also show how the mechanism explains
solar and atmospheric neutrino anomalies through the bimaximal texture at high
scale.Comment: 4 pages REVTEX, 1 Postscript fi
Type II Seesaw Dominance in Non-supersymmetric and Split Susy SO(10) and Proton Life Time
Recently type II seesaw dominance in a supersymmetric SO(10) framework has
been found useful in explaining large solar and atmospheric mixing angles as
well as larger values of while unifying quark and lepton masses.
An important question in these models is whether there exists consistency
between coupling unification and type II seesaw dominance. Scenarios where this
consistency can be demonstrated have been given in a SUSY framework. In this
paper we give examples where type II dominance occurs in SO(10) models without
supersymmetry but with additional TeV scale particles and also in models with
split-supersummetry. Grand unification is realized in a two-step process via
breaking of SO(10) to SU(5) and then to a TeV scale standard model supplemented
by extra fields and an SU(5) Higgs multiplet at a scale about
GeV to give type-II seesaw. The predictions for proton lifetime in
these models are in the range yrs. to yrs.. A number of recent numerical fits to GUT-scale fermion
masses can be accommodated within this model.Comment: 7 pages LaTeX, 3 figures, related areas: hep-ex, hep-th, astro-ph;
Reference added, typo corrected, version to appear in Physical Review
Rapid Detection of Ricin by Sensitising Carboxylated Latex Particles by Ricin Antibodies
Ricin is a highly toxic glycoprotein of Ricinus communis seeds. The toxin was purified and antisera was raised against ricin in rabbit. Polyclonal antibodies were covalently coupled througha water soluble carbodiimide to carboxylated latex particles in various concentrations (800 pg to 3200 pg proteid0.5 ml). Maximum antibodies binding was obtained at 2400 pg to 3200 pgproteid0.5 ml of 2 per cent (wtlvol) latex particles with a sensitivity of 200 pg toxin per test (9 pglml). The sensitivity of latex agglutination test increased as amount of protein bound tothe latex particles increased. The optimum sensitivity of test was recorded when latex particles were sensitised with 2800 pg proteid0.5 ml of latex particles. The reagents were stable for one year without loss of its sensitivity. Developed latex agglutination test is rapid, sensitive, and also does not require trained personnel and costly equipment
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