12790212
Signatures of gaugino mass non-universality in cascade Higgs production at the LHC
Supersymmetric cascades, involving charginos and neutralinos at various stages, contribute in a significant way to Higgs production at the LHC. We explore the nature of such cascades, completely relaxing the universality of the gaugino masses. It is found that the deviation from the scenario with universal gaugino masses would be reflected in the relative production rates for the lightest neutral Higgs and the charged Higgses.
17807975
Search for Higgs bosons of the universal extra dimensions at the large Hadron collider
The Higgs sector of the Universal Extra Dimensions (UED) has a rather involved setup. With one extra space dimension, the main ingredients to the construct are the higher Kaluza-Klein (KK) excitations of the Standard Model Higgs boson and the fifth components of the gauge fields which on compactification appear as scalar degrees of freedom and can mix with the former thus leading to physical KK-Higgs states of the scenario. In this work, we explore in detail the phenomenology of such a Higgs sector of the UED with the Large Hadron Collider (LHC) in focus. We work out relevant decay branching fractions involving the KK-Higgs excitations. Possible production modes of the KK-Higgs bosons are then discussed with an emphasis on their associated production with the third generation KK-quarks and that under the cascade decays of strongly interacting UED excitations which turn out to be the only phenomenologically significant modes. It is pointed out that the collider searches of such Higgs bosons face generic hardship due to soft end-products which result from severe degeneracies in the masses of the involved excitations in the minimal version of the UED (MUED). Generic implications of either observing some or all of the KK-Higgs bosons at the LHC are discussed.
16388458
Probing non-universal gaugino masses via Higgs boson production under SUSY cascades at the LHC: a detailed study
Cascade decays of Supersymmetric (SUSY) particles are likely to be prolific sources of Higgs bosons at the Large Hadron Collider (LHC). In this work, we explore, with the help of detailed simulation, the role of non-universal gaugino masses in the production of the Higgs bosons under SUSY cascades. The analysis is carried out by choosing an appropriate set of benchmark points with non-universal gaugino masses in the relevant SUSY parameter space and then contrasting the resulting observations with the corresponding cases having universal relationship among the same. It is shown that even of data at an early phase of the LHC-run with 10 fb−1 one would be able to see, under favourable situations, the imprint of non-universal gaugino masses by reconstructing various Higgs boson resonances and comparing their rates. With increased accumulated luminosities, the indications would naturally become distinct over a larger region of the parameter space.
118524249
Unusual Higgs boson signal in R-parity violating nonminimal supersymmetric models at the LHC
We predict an unconventional background free signal of the Higgs boson in $R$-parity violating nonminimal supersymmetric models at the Large Hadron Collider (LHC). The signal comprises dilepton plus four hadronic jets and two large displaced vertices. The displaced leptons and jets are coming from the decay of the lightest supersymmetric particle (LSP), which is predominantly a gauge-singlet neutrino. A pair of such LSPs can couple to a Higgs boson, created via gluon fusion. We have analyzed two cases - one corresponding to the tree-level Higgs boson mass and another with the one-loop corrected mass of the Higgs boson. A reliable Higgs mass reconstruction using this signal can lead to discovery at the LHC with center-of-mass energy $\sqrt{s}=14~\rm{TeV}$ and 5 fb$^{-1}$ of integrated luminosity $(\mathcal{L})$. Even at $\sqrt{s}=7~\rm{TeV}$ and $\mathcal{L}$ = 5 fb$^{-1}$, a reasonable number of events are expected. Besides, mass reconstruction of a gauge-singlet LSP can provide an estimate of the seesaw scale.
118190750
Production of two higgses at the Large Hadron Collider in CP-violating MSSM
A bstractProduction of two Higgs bosons is studied in a CP violating supersymmetric scenario at the Large Hadron Collider with Ecm = 14 TeV. There exists a region where a very light Higgs ≲ 50 GeV could not be probed by LEP experiment. This leads to so called ’LEP hole’ region. Recently LHC found a Higgs boson around ~ 125 GeV, which severely constrains the possibility of having lighter Higgs bosons, which cannot be detected, i.e., buried Higgs, in this model. We investigate the possibility of buried Higgs bosons along with the direct and indirect bounds coming from LEP, LHC and other experiments. In particular we take into account the constraints from EDM and from B-observables. We analyse first the case where a Higgs boson mass is around 125 GeV and the other two Higgs masses are below 100 GeV and not observed so far. In the second case the lightest Higgs boson mass is around 125 GeV and the other two are decoupled. We analyse the production of two Higgses and their decay modes leading to various final states for these benchmark points. We perform a collider simulation with PYTHIA and Fastjet where we consider all the major backgrounds. Among the final states we have analysed, we find that 2b + 2τ is promising and the signal significance is 5σ at an integrated luminosity ≲ 10 fb−1. For some benchmark points it is also possible to observe the light Higgs mass peak. We also explore the leptonic final state which could be instrumental in the precision measurement of a very light Higgs.
121399031
Geometrical aspects of magnetic monopoles
The possible topological structures of elementary particles have been investigated to explore the possibility of the existence of magnetic monopoles. It is pointed out that when an elementary charged particle is depicted as an extended body such that the orientation of the internal space (“internal helicity”) defines the fermion number, the global conservation of this does not allow the existence of a magnetic monopole. Again it is argued that when anisotropy is introduced in the microlocal space-time depicting the internal space of hadrons, this gives rise to the internal symmetry algebra and no non-Abelian gauge fields and Higgs scalars are necessary to have a grand unified scheme of interactions. This avoids theSU2 and GUT monopoles. Besides, in this formalism, baryon number corresponds to the orientation or internal helicity of the composite system and the global conservation of this quantum number is found to be a consequence of Lorentz invariance. This forbids the existence of any sort of cosmological monopole in this Lorentz invariant Universe.
122412315
EXTENDED CONFORMAL GROUP, SUPERSYMMETRY, AND GEOMETRICAL PROPERTIES OF HADRONS
We have studied the interrelation among conformal symmetry, internal symmetry and super-symmetry and have shown that extended conformal group which includes, apart from conformal transformation, space, time and conformal reflection can give rise to internal symmetry algebra as well as supersymmetry algebra. To achieve this result, we have dealt with conformal spinors which are taken to be the constituents of the hadrons and these split into two Cartan semispinors or Dirac spinors in the Minkowski space, giving rise to the particle and antiparticle configurations. Supersymmetry is broken here just by the mass term and as such no massless hadron can exist in nature. The internal symmetry arises from the discrete symmetry of reflection. The most significant feature of this formalism is that the symmetry structure helps us to explain the meson-baryon mass difference in an elegant way and the role of fictitious superpartners is completely avoided. Again, any baryon number nonconserving process like proton decay is found to be forbidden by the Lorentz invariance. Finally, it is noted that though the discrete symmetry of reflection is taken to be the origin of the internal symmetry, topological nontrivial structures like strings do not appear here and this also avoids the possibility of the nonconservation of global charge.
122629561
Stochastic field theory at finite temperature and equilibrium states in quantum statistical mechanics
Stochastic field theory at finite temperature, when it is formulated from stochastic mechanics, which incorporates Brownian motion in both the external, as well as the internal, space of a particle, and the external and internal fields, and which are written as thermal doublets, gives rise to finite temperature quantum field theory in Minkowski space. The Haag–Hugenholtz–Winnik, (HHW) formalism of modular conjugation and the Tomita–Takesaki theory of modular Hilbert algebra then follow from this finite temperature quantum field theoretical formalism. It is shown that there is an inherent discrete Z2 symmetry among the fields of the doublet, and the equilibrium condition is ensured by this symmetry. When this symmetry is spontaneously broken, thermodynamical equilibrium is destroyed.
121542781
Equivalence of three-dimensional Ising model and fermionic string
The equivalence of a three-dimensional Ising model and a fermionic string as pointed out by Polyakov has been established here from the point of view of the geometrical aspects of a Polyakov string.
117394387
Half orbital angular momentum and Lorentz invariance in an anisotropic space
The possible existence of half orbital angular momentum is studied in the context of an anisotropic microlocal space--time. It is shown that through l = 1/2 poses serious problems in an isotropic space, that is acceptable in an anisotropic space and is of relevance in determining the internal symmetry of hadrons. A crucial feature of l = 1/2 in such a space is that l/sub z/ is a conserved quantity and though L/sup 2/ is not a good operator, J/sup 2/ = (L+1/2/sup a/)/sup 2/ is an 0(3) invariant where -1/2(a x r) = ..mu.. is the measure of anisotropy given by the commutation of linear momentum components. It is pointed out that when the angular momentum operator is modified so that we have a 'conserved angular momentum' in this space, the system resembles the motion of a charged particle in the field of a magnetic monopole or a top motion. An oscillator representation of this formalism has been develo