Searches for beyond Standard Model Higgs bosons at CMS

A search for neutral Higgs bosons in the minimal supersymmetric extension of the Standard Model (MSSM) decaying to a pair of b quarks or a pair of tau leptons, using events recorded by the CMS experiment at the LHC in 2011 and 2012 at the centre-of-mass energy of 7 TeV and 8 TeV respectively, is presented. The result is also presented for a search for the charged Higgs boson that can be produced in the top quark decay with subsequent decay of H+ in tau and neutrino. Results are also reported from a search for non-standard-model Higgs boson decays to pairs of new light bosons, each of which decays into the di-muon final state.Comment: Submitted to the proceedings of "The European Physical Society Conference on High Energy Physics - EPS-HEP2013, 18-24 July 2013,Stockholm, Sweden

Measurement of the Z boson plus two b-jets cross section in CMS with 100 pb-1

The cross section for production of Z bosons with two associated b-jets, and Z decaying to leptons, can be measured at the LHC with about 100 pb-1 of data. We use simulated data to study possible strategies for an early measurement of this process with the CMS detector. The rate and kinematic properties of this final state needs to be well understood because it constitutes a large fraction of the total backgrounds to several of the Higgs discovery channels at the LHC.Comment: 5 pages, 3 figures, submitted to the proceedings of Physics at LHC 2008, Split, Croati

Improving Heavy Dijet Resonance Searches Using Jet Substructure at the LHC

The search for new physics at high energy accelerators has been at the crossroads with very little hint of signals suggesting otherwise. The challenges at a hadronic machine such as the LHC compounds on the fact that final states are swamped with jets which one needs to understand and unravel. A positive step in this direction would be to separate the jets in terms of their gluonic and quark identities, much in similar spirit of distinguishing heavy quark jets from light quark jets that has helped in improving searches for both neutral and charged Higgs bosons at the LHC. In this work, we utilise this information using the jet substructure techniques to comment on possible improvements in sensitivity as well as discrimination of new resonances in the all hadronic mode that would be crucial in pinning down new physics signals at HL-LHC, HE-LHC and any future 100 TeV hadron collider.Comment: 21 pages, 3 tables, 9 figure

Leptoquark-assisted Singlet-mediated Di-Higgs Production at the LHC

At the LHC, the gluon-initiated processes are considered to be the primary source of di-Higgs production. However, in the presence of a new resonance, the light-quark initiated processes can also contribute significantly. In this paper, we look at the di-Higgs production mediated by a new singlet scalar. The singlet is produced in both quark-antiquark and gluon fusion processes through loops involving a scalar leptoquark and right-handed neutrinos. With benchmark parameters inspired from the recent resonant di-Higgs searches by the ATLAS collaboration, we examine the prospects of such a resonance in the TeV-range at the High-Luminosity LHC (HL-LHC) in the $b\bar{b} \tau^{+}\tau^{-}$ mode with a multivariate analysis. We obtain the $5\sigma$ and $2\sigma$ contours and find that a significant part of the parameter space is within the reach of the HL-LHC.Comment: 11 pages, 7 figures, 3 tables. Published versio

ROLE OF PROTECTION PROVIDED BY EMBLICA OFFICINALIS LINN. AGAINST RADIATION AND LEAD INDUCED HISTOLOGICAL CHANGES IN THE JEJUNUM OF SWISS ALBINO MICE

oai:ojs.pkp.sfu.ca:article/1Exposure to ionizing radiation increases the production of the reactive oxygen species (ROS) leading the irradiated cells into a state of oxidative stress. Furthermore, Lead exposure along with ionizing radiation can potentially become toxic to the tissues due to the heightened oxidative stress. In the present study adult male Swiss albino mice were procured and divided into seven groups. Group (II to IV) serving as control, received sub lethal dose (3.0 Gy or 6.0Gy) and /or lead acetate (20ppm) in drinking water ad libitum. The experimental groups (V to VII) were given aqueous solution of Emblica (1000 mg/ Kg b.wt./ animal/ day) orally seven days prior to radiation and/or lead acetate treatment. Sham- irradiated animals of Group I served as normal. Animals of all the groups were autopsied at each post treatment interval of 1, 2, 4, 7, 14 and 28 days. After the experiments observed number of lesions in the intestinal epithelium from outer coat to inner mucosa. Loosened sub mucosa with hyperaemia and hemorrhage, shortened crypts and a number of apoptotic cells with severe cytoplasmic variations were noted. Villi had a rough surface, wavy epithelium and hydropic degeneration up to day-2 and thereafter, a recovery from intestinal lesions was initiated and noticed till the last autopsy interval. After the combined exposure of gamma radiation and lead acetate, Group IV exhibited same pattern of damage but severe histopathological alteration than individual exposure of radiation or lead acetate indicating “synergistic “effect. Process of recovery started on day-14 after the combined treatment but the process was slow. The Combined treatment showed synergistic effect. In experimental groups less severe radiolesions and an early onset of recovery was observed. Therefore it may be deduced that Emblica is a good herbal radioprotector and may be useful for the clinical applications in human beings during radiotherapy.

Evidence that Differences in Fructosamine-3-Kinase Activity May be Associated with the Glycation Gap in Human Diabetes

The phenomenon of a discrepancy between glycated haemoglobin levels and other indicators of average glycaemia may be due to many factors but can be measured as the glycation gap (GGap). This GGap is associated with differences in complications in patients with diabetes and may possibly be explained by dissimilarities in deglycation in turn leading to altered production of Advanced Glycation End (AGE) products. We hypothesised that variations in the level of the deglycating enzyme Fructosamine-3-kinase (FN3K) might be associated with the GGap. We measured erythrocyte FN3K concentrations and enzyme activity in a population dichotomised for a large positive or negative GGap. FN3K protein was higher and we found a striking 3-fold greater activity (323%) at any given FN3K protein level in the erythrocytes of the negative compared with positive GGap groups. This was associated with lower AGE levels in the negative GGap group (79%), lower pro-inflammatory adipokines (Leptin/Adiponectin ratio) (73%) and much lower pro-thrombotic PAI-1 levels (19%). We conclude that FN3K may play a key role in the GGap and thus diabetes complications such that FN3K may be potential predictor of the risk of diabetes complications. Pharmacological modifications of its activity may provide a novel approach to their prevention

Search for heavy resonances in the W/Z-tagged dijet mass spectrum in pp collisions at 7 TeV

A search has been made for massive resonances decaying into a quark and a vector boson, qW or qZ, or a pair of vector bosons, WW, WZ, or ZZ, where each vector boson decays to hadronic final states. This search is based on a data sample corresponding to an integrated luminosity of 5.0 fb^-^1 of proton-proton collisions collected in the CMS experiment at the LHC in 2011 at a center-of-mass energy of 7 TeV. For sufficiently heavy resonances the decay products of each vector boson are merged into a single jet, and the event effectively has a dijet topology. The background from QCD dijet events is reduced using recently developed techniques that resolve jet substructure. A 95% CL lower limit is set on the mass of excited quark resonances decaying into qW (qZ) at 2.38 TeV (2.15 TeV) and upper limits are set on the cross section for resonances decaying to qW, qZ, WW, WZ, or ZZ final states.Peer Reviewe