Lydia Roos
(IN2P3/LPNHE)
07/12/2016, 12:00
The LHC has delivered a large amount of data at a center of mass energy of 13 TeV.
The experimental sensitivity with this data set is equivalent to the one from run-1 for the Higgs boson (125 GeV),
and surpasses it for searches for higher mass Higgs-like particles.
This talk will review recent ATLAS results on both of these topics.
Mr
Mirkoantonio Casolino
(IFAE - UAB)
07/12/2016, 14:30
Since the discovery of a Higgs boson by the ATLAS and CMS experiments at the Large Hadron Collider (LHC), the emphasis has shifted towards measurements of its properties and the search for less sensitive channels in order to explore any deviation from the Standard Model. The WH and ZH production modes, jointly denoted as VH, provide high sensitivity channels to observe Higgs boson decays to a...
07/12/2016, 15:30
Ms
Sibaliso Mhlanga
(Student (iThemba/University of Cape Town)
The performance of a particle collider is characterised by the luminosity, that is, the number of collisions produced over time per cross-section. Therefore, the luminosity is a necessity in the determination of the cross section for a reaction process. Also, it is dependent on the number of particles in each colliding beam as well as on the size of the overlap of both beams at the collision...
Dr
Michaël Ughetto
(Stockholm University)
Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results for searches for supersymmetric (SUSY) particles, with focus on those obtained using proton-proton collisions at a centre of mass energy of 13 TeV.
Prof.
Aldo Deandrea
(IPNL - University Lyon 1)
We consider present constraints on models with more than one Higgs boson, both from the LHC data and from other sources in order to explore the possibility of constraining scalar or pseudoscalar particles lighter than the 125 GeV Higgs boson. Contrary to naive expectations, such a lighter particle is not yet completely excluded by present data. We show with a simplified analysis that some new...
Prof.
Elena Bratkovskaya
(GSI and Frankfurt Uni.)
We study the effect of the chiral symmetry restoration (CSR) in
heavy-ion collisions from $\sqrt{s_{NN}}$=3-160 GeV within the
Parton-Hadron-String Dynamics (PHSD) transport approach. The PHSD
includes the deconfinement phase transition as well as essential
aspects of CSR in the dense and hot hadronic medium, which are
incorporated in the Schwinger mechanism for the hadronic...
Mr
Mohammed Omer Khojali
(University of the Witwatersrand)
We explicitly test, in a simplified 5-dimensional model with $SU(5)$, $SU(5) \times U(1)^{\prime}$ and $G_{2}$ gauge symmetry, the evolution
of the gauge couplings. We assume that all the matter fields are propagating in the bulk, and consider orbifolds based on Abelian discrete groups which lead to 5-dimensional gauge theories compactified on an $S^{1}/Z_{2}$. The gauge couplings evolution...
Mr
Stefan von Buddenbrock
(University of the Witwatersrand)
The Standard Model (SM) Higgs boson, with its experimental discovery in 2012, has long been an interesting particle to study with the intention of exploring new physics ideas beyond the SM (BSM). Its properties are still not well understood, and there are several features in LHC Run 1 and Run 2 data which point at the possibility of extensions to the SM Higgs sector. This work explores the...
Prof.
Blazenka Melic
(Rudjer Boskovic Institute)
The search for the Flavor Changing Neutral Current (FCNC) processes, has been one of the
leading tools to test the Standard Model (SM), in an attempt of either discovering or putting
stringent limits on the new physics scenarios.
Within the SM, there are no FCNC transitions at
tree level, mediated by the Higgs Boson. These processes are severely suppressed by the unitarity
constraints of...
Dr
Katharina Mueller
(University of Zurich)
The LHCb detector with its excellent momentum resolution and flexible trigger strategy is ideally suited for measuring heavy quark and quarkonia production.
Recent LHCb measurements of inclusive and differential cross-sections of the production of J/\psi and Upsilon as well as charm, bottom and top quarks in pp collisions at different centre of mass energies are presented. The emphasis lies...
Prof.
Yaquan Fang
(Institute of High Energy Physics)
The discovery of a light Higgs particle h0 (125 GeV) opens up new prospect for searching heavier Higgs boson(s) at the LHC Run-2, which will unambiguously point to new physics beyond the standard model (SM). We study the detection of a heavier neutral Higgs boson H0 via di-Higgs production channel at the LHC (14 TeV) with H0 → h0h0 →bbγ γ ,W W*γ γ , WW*WW*. This directly probes the Hhh cubic...
Mr
Nicolas Deutschmann
(IPN Lyon / CP3 Louvain)
The Effective Field Theory approach is a fruitful way of putting model independent constraints on heavy new physics.
As the Higgs sector is one of the most popular candidates for deviations from the Standard Model prediction,
it is particularly important that the constraints extracted from the experimental data on the Higgs boson be as meaningful as possible,
which entails making accurate...
Dr
Yasser Corrales Morales
(Universita e INFN Torino (IT))
The production of identified hadrons in proton-proton collisions is frequently studied as a reference for the investigation of the strongly-interacting medium created in heavy-ion collisions. In addition, measurements in pp and p-Pb collisions as a function of event multiplicity at LHC energies have shown some features reminiscent of those related to collective effects in Pb--Pb collisions....
Mr
Abdullah Ibrahim
(University of Cape Town)
We study the cancellation of both collinear and infrared divergences in a process where a massless electron scattered off of a static point charge. We found that the collinear divergences have been eliminated by the application of the well known KLN theorem. The application of the KLN theorem requires adding the absorption of a photon which spoils the cancellation of the IR divergences. We...
Dr
Shoaib Munir
(Korea Institute for Advanced Study)
Most models of new physics contain extended Higgs sectors with multiple Higgs bosons. One of these Higgs bosons should have properties consistent with the Standard Model (SM)-like one discovered recently at the Large Hadron Collider (LHC). At the same time, the remaining ones should be consistent with the negative searches corresponding to a wide range of their probable masses at the Large...
Mr
Andriniaina Narindra Rasoanaivo
(University of Cape Town)
We present a novel technique for the calculation of the probability for emission of an arbitrary number of gluons radiated from a high-pT probe of the QGP. Our work is an extension of the maximal helicity violating (MHV) method in which the usual soft-collinear factor is classified according to its symmetry under gluon permutations.
For the purposes of illustration, we show the explicit...
Ms
Joyful Mdhluli
(University of the Witwatersrand)
With the prediction that the plastic scintillators in the Gap region of the Tile Calorimeter will sustain a significantly large amount of radiation damage during the HL-LHC run time, the current plastic scintillators will need to be replaced during the phase 2 upgrade in 2018. The scintillators in the gap region were exposed to a radiation environment of up to 10 kGy/year during the first run...
Mr
Tshidiso Molupe
(University of the Witwatersrand)
The discovery of the Scalar Higgs Boson, h, in July 2012 means that the particle spectrum of the Standard Model (SM) is complete. New questions arise, whether the electroweak symmetry breaking mechanisn in the SM is really complete, and whether there are more particles with scalar like properties, like the Higgs Boson. The Wits HEP group has postulated the existince of a heavy scalar, H, with...
Dr
Massimiliano Marchisone
(University of the Witwatersrand and iThemba LABS)
The LHC heavy-ion physics program aims at investigating the properties of QCD matter at high temperature and energy density, where a deconfined partonic state of matter called Quark-Gluon Plasma (QGP) is formed. Measurements of open heavy-flavour production in ultra-relativistic nucleus-nucleus collisions are expected to provide essential information about the QGP properties since heavy quarks...
Prof.
Christopher Neu
(University of Virginia)
The incredible performance of the LHC in 2016 has provided the collider experiments the opportunity to study the physics of the fundamental world at the largest energies and smallest length scales ever probed. In this talk I will summarize some recent, high-profile results from the CMS experiment, one of two general-purpose experiments at the LHC. The presentation will touch on all aspects of...
Benjamin Doenigus
(Institute for Nuclear Physics, Goethe University Frankfurt, Frankfurt, Germany)
The high collision energies reached at the LHC lead to significant production yields of light (anti-)(hyper-)nuclei in proton-proton, proton-lead and, in particular, lead-lead collisions. The excellent particle identification capabilities of the ALICE apparatus allow for the detection of these rarely produced particles. Furthermore, the good vertexing performance gives the possibility to...
Prof.
Bernd Stelzer
(Simon Fraser University)
Since 2015, the LHC is operating at a center-of-mass energy of 13 TeV and the ATLAS detector has collected data very efficiently during this time. The increased centre-of-mass energy provides a unique opportunity to find new Physics beyond the Standard Model (BSM) at the LHC. This talk will summarize the latest ATLAS results on BSM searches in a large number of final states which target...
Jacopo Pazzini
(Padova University, INFN)
Searches for physics beyond the Standard Model performed with the CMS experiment are summarized. The results are based on the data collected from proton-proton collisions at a center of mass energy of 13 TeV in 2015 and 2016, corresponding to 2.5 and 12.9 fb-1 respectively.
Mr
Trambak Bhattacharyya
(Variable Energy Cyclotron Centre, Kolkata, India)
We analytically investigate the thermodynamic variables of a hot and dense system in the framework of the Tsallis non extensive classical statistics in the massless and in the massive cases. Emphasis has been put on the method used to deal with the massive case where the cumbersome momentum integral has been replaced by the simpler ones. In addition to that, we study the effect of Tsallis...
Prof.
Alan Cornell
(National Institute for Theoretical Physics)
In previous works we have studied spin-3/2 fields near D-dimensional Schwarzschild black holes. The techniques we developed in that case have now been extended here to show that it is possible to determine the potential of spin-3/2 fields near D-dimensional black holes by exploiting the radial symmetry of the system. This removes the need to use the Newman-Penrose formalism, which is difficult...
Prof.
Alan Cornell
(National Institute for Theoretical Physics)
In previous works we have studied spin-3/2 fields near D-dimensional Schwarzschild black holes. The techniques we developed in that case have now been extended here to show that it is possible to determine the potential of spin-3/2 fields near D-dimensional black holes by exploiting the radial symmetry of the system. This removes the need to use the Newman-Penrose formalism, which is difficult...
Dr
kate shaw
(The International Centre for Theoretical Physics)
Recent results from the ATLAS experiment at CERN on Standard Model and Top quark physics are presented, for analysis using the full 8 TeV dataset and fresh results from 13 TeV analysis.
Prof.
Bruce Mellado
(University of the Witwatersrand)
The Large Electron Proton Collider (LHeC) is a project that is envisioned as an upgrade of the Large Hadron Collider (LHC). The physics programme of the LHeC is vast. It plays a critical role for the measurement precise measurement of parton density functions in a wide range of the Bjorken x and the QCD interaction constant, alpha$_S$. These are essential to fully exploit the physics potential...
Dr
Deepak Kar
(University of Witwatersrand)
By measuring the substructure of a jet, one can assign it a quark or gluon tag. In this talk, we confront the challenges faced when going beyond this leading-order understanding, using both parton shower generators and first-principles calculations to assess the impact of higher-order perturbative and nonperturbative physics. Working in the idealized context of electron-positron...
Prof.
Ettore Focardi
(University of Florence)
The CMS experiment had a very good start of its Physics Program at the Large Hadron Collider (LHC). One of the main questions in Particle Physics, what is the origin of the particle masses, was partially answered with the Physics runs in 2011 and 2012 when LHC delivered an integrated luminosity of ~25 fb-1 and gave as result the discovery of a Higgs boson with mass of ~125 GeV. The study of...
Mr
Alessio Piucci
(Physikalisches Institut Heidelberg)
During the LHC Run 1 the LHCb experiment has successfully performed a large number of high precision measurements in heavy flavour physics using 3 $fb^{-1}$ collected at centre-of-mass energies of 7 $TeV$ and 8 $TeV$.
In LHC Run 2 the LHCb is expected to integrate an additional 5 $fb^{-1}$ data, however many of the measurements will remain limited by statistics.
For this reason LHCb will...
Dr
Mukesh Kumar
(University of the Witwatersrand)
In this work we are hypothesising three real scalar bosons ($H$, $S$, $\chi$) in a theory beyond the Standard Model. Our aim is to formulate a proper theory by considering an effective approach and as well by considering two Higgs doublet model. Further we study a viable parameter space to constraint the associated parameter spaces like couplings and masses of these bosons via experimental...
Dr
Victoria Martin
(University of Edinburgh)
The High Luminosity run of the Large Hadron Collider (LHC) will start in 2026 and aims to collect $3000\;\mathrm{fb}^{-1}$ of proton-proton collisions by 2037. This enormous dataset will increase the discovery potential of the LHC and allow precision measurements of Standard Model processes. However, the very high instantaneous luminosity of $5-7 \times 10^{34}\;\mathrm{cm^{-2}\, s^{-1}}$...
Dr
Steve Muanza
(CPPM Marseille, CNRS-IN2P3 & Aix-Marseille University)
Contrarily to past high energy colliders, the LHC is a charge asymmetric machine. Therefore most of the hard scattering processes producing electrically charged final states have a positive integral charge asymmetry. The latter quantity, denoted AC, is easily measurable in event topologies bearing an odd number of hard and isolated charged leptons.
We have brought to light the strong...
Kgotlaesele Senosi
(University of Cape Town (iThemba LABS))
ALICE (A Large Ion Collider Experiment) is designed and optimized to study ultra-relativistic heavy-ion collisions at the LHC, in which a hot and dense, strongly-interacting medium is created. Vector bosons (W and Z) are produced in hard scattering processes and interact weakly with the medium formed in heavy-ion collisions. Thus, they present a suitable reference for processes which are...
Prof.
Domenec Espriu
(University of Barcelona)
We re-examine the issue of wave function renormalisation for unstable particles in the presence of electroweak interactions and its relation with the renormalisation of the CKM mixing matrix elements. We show that a proper LSZ-compliant prescription leads to gauge independent amplitudes. The resulting wave function renormalisation constants necessarily possess absorptive parts, but they comply...
