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.
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.
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.
120699236
TOPOLOGICAL ASPECTS OF CHIRAL ANOMALY, ORIGIN OF MASS AND ELECTROWEAK THEORY
It is here shown that the topological property of a fermion which gives rise to the fermion number and is related to chiral anomaly may be taken to lead to weak interaction gauge bosons when currents are written in chiral form. The gauge bosons attain mass topologically through the generation of internal helicities and thus no Higgs scalar is needed to have spontaneous symmetry breaking. Moreover the group structure SU(2)×U(1) is inbuilt here for electroweak unification. The Weinberg angle gets a physical meaning and strangeness changing neutral lepton current interaction is automatically forbidden. This formalism also suggests that at very high temperature, weak interaction will be of long range in nature.
118949681
QUANTUM HALL SKYRMIONS IN THE FRAMEWORK OF O(4) NONLINEAR SIGMA MODEL
A new framework for quantum Hall skyrmions in O(4) nonlinear sigma model is studied here. The size and energy of the skyrmions are determined incorporating the quartic stability term in the Lagrangian. Moreover, the introduction of a θ-term determines the spin and statistics of these skyrmions.
118027237
Dual-parton model and the high-energy pion-nucleon scattering in the forward and backward regions
SummaryOn the basis of the dynamical dual-parton model of strong interactions as discussed in an earlier paper, we study here the high-energy processes π±p→π±p, π−p→nπ0 in the forward and backward regions. To incorporate the concept of duality, it is assumed that any two spin-1/2 pointlike constituents (partons) can form a π-meson cluster in the structure of a nucleon and the basic interaction involved in MB scattering is the interaction of the incident meson with the π-meson in the structure of the nucleon. To calculate the amplitudes for the relevant processes, we also take into account a factor corresponding to the structural re-arrangement of partons involved in duality diagrams. The differential cross-sections as well as the energy dependence are found to be in excellent agreement with the experimental data. Also, this model can nicely explain the fact that all these processes in the forward regions are characterized by dips in differential cross-sections, but in the backward region, though the processes π+p→pπ+, π−p→nπ0 are characterized by dips, no such dip occurs in the process π−p→pπ−.RiassuntoSulla base del modello dinamico del partone duale per le interazione forti, come discusso in un precedente lavoro, si studiano i processi di alta energia π±p→π±p, π−p→nπ0 nella regione in avanti e in quella all’indietro. Per comprendere il concetto di dualità, si è supposto che ogni due costituenti (partoni) puntiformi di spin 1/2 possano formare un ammasso di mesoni π nella struttura di un nucleone e l’interazione di base inclusa nello scattering MB sia l’interazione del mesone incidente col mesone π nella struttura del nucleone. Per calcolare le ampiezze dei relativi processi, teniamo inoltre conto di un fattore corrispondente al riordinamento strutturale dei partoni inclusi nei diagrammi di dualità. Si è trovato che le sezioni d’urto differenziali, così come la dipendenza dall’energia, sono in eccellente accordo con i dati sperimentali. Inoltre, questo modello può spiegare bene il fatto che tutti questi processi nelle regioni in avanti sono caratterizzati da abbassamenti delle sezioni d’urto differenziali, ma nella regione all’indietro, anche se i processi π+p→pπ+, π−p→nπ0 sono caratterizzati da abbassamenti, nessuno di questi abbassamenti si ha nel processo π−p→pπ−.РеэюмеНа основе динамической дуальной партонной модели сильных вэаимодействий, рассмотренной в предыдушей статье, мы эдесь исследуем процессы π±p→π±p и π−p→nπ0 при высоких знергиях в направлениях вперед и наэад. Чтобы включить концепцию дуальности, принимается, что два любых точечных общекта со спином 1/2 (партоны) могут обраэовать тс-меэонный кластер в структуре нуклона, и что основное вэаимодействие, участвуюшее в МВ рассеянии, представляет вэаимодействие падаюшего меэона с ?-меэоном в структуре нуклона. Чтобы вычислить амплитуды для соответствуюших процессов, мы также учитываем фактор, соответ-ствуюший структурной перегруппировке партонов, участвуюших в дуальных диаг-раммах. Дифференциальные поперечные сечения, а также знергетическая эависи-мость прекрасно согласуются с зкспериментальными данными. Кроме того, зта медель может хорощо общяснить тот факт, что зти процессы в направлении вперед характериэуются минимумами в дифференциальных поперечных сечениях, но в направлении наэад такой минимум отсутствует в продессе π−p→pπ−, хотя для процессов π+p→pπ+, и π−p→nπ0 характерны минимумы.
120507252
Stochastic field theory and finite-temperature supersymmetry
The finite‐temperature behavior of supersymmetry is considered from the viewpoint of stochastic field theory. To this end, it is considered that Nelson’s stochastic mechanics may be generalized to the quantization of a Fermi field when the classical analog of such a field is taken to be a scalar nonlocal field where the internal space is anisotropic in nature such that when quantized this gives rise to two internal helicities corresponding to fermion and antifermion. Stochastic field theory at finite temperature is then formulated from stochastic mechanics which incorporates Brownian motion in the external space as well as in the internal space of a particle. It is shown that when the anisotropy of the internal space is suppressed so that the internal time ξ0 vanishes and the internal space variables are integrated out one has supersymmetry at finite temperature. This result is true for T=0, also. However, at this phase equilibrium will be destroyed. Thus for a random process van Hove’s result involving q...
122605004
Clan structure and intermittency in proton-nucleus interactions at high energy
In this paper we examine the similarity between clan structure and self-similar cascading in high energy proton-nucleus interactions at 70 GeV/c in emulsion. The investigation shows that the negative bionomial fitting parameterk can be used for the evaluation of factorial moments in intermittency studies and that these exhibit similar behaviour with those derived from nonstatistical procedure. The results of our study signify compatibility between clan cascading and self-similar cascading in soft hadroization processes.