In this lecture I give an introduction to technicolor and extended technicolor theories. I discuss the issues models of dynamical electroweak symmetry breaking struggle with and propose how non QCD-like dynamics, such as a `walking' or nearly-conformal technicolor coupling, can invalidate many conventional arguments against technicolor. I provide a short discussion of AdS/CFT-inspired extra-dimensional (Higgsless) models and their similarities and differences with older 4D technicolor models. To conclude, a summary of some possible LHC signatures is given.
Condensates of colored fermions driving electroweak symmetry breaking could give rise to a light pseudoscalar that would show up in the Higgs search at the LHC. The branching ratios of its decay will distinguish it from the Higgs and illuminate its origin. In particular the colored fermions may be the techniquarks of a one family technicolor theory or the quarks of a strongly interacting fourth family. The former has more difficulties in this context.
LHC searches for the standard model Higgs Boson in γγ or ττ decay modes place strong constraints on the light technipion state predicted in technicolor models that include colored technifermions. Compared with the standard Higgs Boson, the technipions have an enhanced production rate (largely because the technipion decay constant is smaller than the weak scale) and also enhanced branching ratios into di-photon and di-tau final states (largely due to the suppression of WW decays of the technipions). Recent ATLAS and CMS searches for Higgs bosons exclude the presence of technipions with masses f…
We construct a Technicolor model which provides masses for the electroweak gauge bosons and for all the Standard Model matter fields. Starting from an ultraviolet complete supersymmetric technicolor, we propose a scenario where all elementary scalars, gauginos, and higgsinos are decoupled at an energy scale substantially higher than the electroweak scale, therefore avoiding the little hierarchy problem of the minimal supersymmetric standard model. The resulting low energy theory has an SU(3) global symmetry whose breaking to SO(3) leads to electroweak symmetry breaking. We study in detail the …
The LHC Higgs can be identified as the technidilaton, a composite scalar, arising as a pseudo Nambu-Goldstone boson for the spontaneous breaking of scale symmetry in walking technicolor. One interesting candidate for the walking technicolor is the QCD with the large number of fermion flavors, involving the one-family model having the eight-fermion flavors. The smallness of the technidilaton mass can be ensured by the generic walking feature, Miransky scaling, and the presence of the "anti-Veneziano limit" characteristic to the large-flavor walking scenario. To tell the standard-model Higgs fro…
Walking technicolor, having a large anomalous dimension $γ_m \simeq 1$ and approximate scale symmetry, predicts Technidilaton, a light composite Higgs as a pseudo-Nambu-Goldstone boson of the approximate scale symmetry, which can be identified with the 125 GeV boson discovered at LHC. I will describe how such a {\it weakly coupled light composite scalar} can be dynamically realized in the {\it strongly coupled dynamics}, and can be fit to the current data at LHC, based on the ladder-like computation and the holographic one. I will also present results of our lattice collaboration (LatKMI Colla…
The topcolor-assisted technicolor (TC2) model predicts some light pseudo goldstone bosons (PGBs), which may be accessible at the LHC or ILC. In this work we study the pair productions of the charged or neutral PGBs at the LHC and ILC. For the productions at the LHC we consider the processes proceeding through gluon-gluon fusion and quark-antiquark annihilation, while for the productions at the ILC we consider both the electron-positron collision and the photon-photon collision. We find that in a large part of parameter space the production cross sections at both colliders can be quite large co…
The topcolor-assisted technicolor (TC2) model predicts a number of neutral scalars like the top-pion ($π^0_t$) and the top-Higgs ($h^0_t$). These scalars have flavor-changing neutral-current (FCNC) top quark couplings, among which the top-charm transition couplings may be sizable. Such FCNC couplings induce single top productions associated with a neutral scalar at the CERN Large Hadron Collider (LHC) through the parton processes $cg \to t π_t^0$ and $cg \to t h_t^0$. In this note we examine these productions and find their production rates can exceed the $3σ$ sensitivity of the LHC in a large…
The top-seesaw assisted technicolor (TC) model, which was proposed recently to explain the 126 GeV Higgs mass discovered by the Large Hadron Colliders (LHC), predicts light and heavy charged Higgs bosons in addition to the neutral Higgses. In this paper we will study the pair productions of the charged Higgs, proceeding through gluon-gluon fusion and quark-anti-quark annihilation, at the LHC in the frame of the top-seesaw assisted TC model. We find that in a large part of parameter space the production cross sections of the light charged Higgs pair at the LHC can be quite large compared with t…
The topcolor-assisted technicolor (TC2) model predicts the existence of the charged top-pions ($π_t^\pm$), whose large couplings with the third generation fermions will induce the charged top-pion production associated with the bottom and anti-bottom quark pair at the CERN Large Hadron Collider (LHC) through the parton processes $c\bar b \to π_t^+ b \bar b$ and $u\bar d(c\bar s) \to π_t^+ b \bar b$. In this paper we examine these productions and find that, due to the small Standard Model backgrounds, their production rates can exceed the $3σ$ sensitivity of the LHC in a large part of parameter…
We study the contributions of the neutral pseudo Goldstone bosons (technipions and top-pions) to the t anti-t production cross sections at the Tevatron and the LHC in topcolor-assisted multiscale technicolor (TOPCMTC) models via the gluon-gluon fusion process from the loop-level couplings between the pseudo Goldstone bosons and the gluons. The MRS set A' parton distributions are used in the calculation. It is shown that the new CDF datum on the t anti-t production cross section gives constraints on the parameters in the TOPCMTC models. With reasonable values of the parameters in TOPCMTC models…
We investigate the potential of the Large Hadron Collider (LHC) to probe one of the most compelling Beyond the Standard Model (BSM) frameworks --- Walking Technicolor (WTC), involving strong dynamics and having a slowly running (walking) new strong coupling. For this purpose we use recent LHC Run2 data to explore the full parameter space of the minimal WTC model using dilepton signatures from heavy neutral $Z^{\prime}$ and $Z^{\prime\prime}$ resonances predicted by the model. This signature is the most promising one for discovery of WTC at the LHC for the low-intermediate values of the $\tilde…
We analyze the potential of the Large Hadron Collider (LHC) to observe signatures of phenomenologically viable Walking Technicolor models. We study and compare the Drell-Yan (DY) and Vector Boson Fusion (VBF) mechanisms for the production of composite heavy vectors. We find that the heavy vectors are most easily produced and detected via the DY processes. The composite Higgs phenomenology is also studied. If Technicolor walks at the LHC its footprints will be visible and our analysis will help uncovering them.
In a topcolor-assisted technicolor model (TC2) with large FCNC top quark couplings, we study its correlated contributions to the top quark forward-backward asymmetry ($A_{FB}$) at the Tevatron, the top charge asymmetry ($A_{C}$) and the triple-top production at the LHC. Under current constraints on the top quark from the LHC and Tevatron(such as the total and differential production rates), we scan the parameter space of such a TC2 model. We find that in the allowed parameter space the TC2 model can explain the Tevatron measured $A_{FB}$ at $2σ$ level, but meanwhile significantly enhance $A_{C…
We consider scenarios in which the 125 GeV resonance observed at the Large Hadron Collider is a Technicolor (TC) isosinglet scalar, the TC Higgs. By comparison with quantum chromodynamics, we argue that the couplings of the TC Higgs to the massive weak bosons are very close to the Standard Model (SM) values. The couplings to photons and gluons are model-dependent, but close to the SM values in several TC theories. The couplings of the TC Higgs to SM fermions are due to interactions beyond TC, such as Extended Technicolor: if such interactions successfully generate mass for the SM fermions, we …
It is shown that a technicolor theory containing a color-octet technipion, usually denoted by $P^{0'}_{8}$, will give rise to an enhancement of $t \bar t$ production at the Tevatron, LHC and SSC, via the process $gg \rightarrow P^{0'}_{8} \rightarrow t \bar t$. The relevant cross-sections are computed taking into account the large lower bound on the top mass coming from the "top search" experiments at LEP and CDF. At the LHC and SSC, the signal is found to be comparable to the QCD background, making the process quite accesible.
We propose to probe the topcolor-assisted technicolor (TC2) model from the top-charm associated productions at the LHC, which are highly suppressed in the Standard Model. Due to the flavor-changing couplings of the top quark with the scalars (top-pions and top-Higgs) in TC2 model, the top-charm associated productions can occur via both the s-channel and t-channel parton processes by exchanging a scalar field at the LHC. We examined these processes through Monte Carlo simulation and found that they can reach the observable level at the LHC in quite a large part of the parameter space of the TC2…
Under the assumption that the dijet excess seen by the CDF Collaboration near 150 Gev in Wjj production is due to the lightest technipion of the low-scale technicolor process $ρ_T \rightarrow W π_T$, we study its observability in LHC detectors with 1-5 fb^{-1} of data. We find that cuts similar to those employed by CDF are unlikely to confirm its signal. We propose cuts tailored to the LSTC hypothesis and its backgrounds at the LHC that can reveal $π_T \rightarrow jj$. We also stress the importance at the LHC of the isospin-related channel $ρ^{\pm}_T \rightarrow Zπ^{\pm}_T \rightarrow \ell\ell…
We study the top quark pair production process p+p(anti-p)-->top+antitop in various kinds of technicolor (TC) models at the Fermilab Tevatron Run II and the CERN LHC. The s-channel neutral pseudo-Goldstone bosons (PGB's) contribute dominately to the production amplitudes from its coupling to the gluons through the triangle loops of techniquarks and the top quark. Cross sections in different TC models with s-channel PGB contributions are calculated. It is shown that the PGB effects can be experimentally tested and different TC models under consideration can be distinguished at the LHC. Therefor…
The topcolor-assisted technicolor (TC2) theory predicts tree-level flavor-changing neutral-current (FCNC) top quark Yukawa couplings with top-pions. Such FCNC interactions will induce like-sign top quark pair productions at CERN Large Hadron Collider (LHC). While these rare productions are far below the observable level in the Standard Model and other popular new physics models such as the Minimal Supersymmetric Model, we find that in a sound part of parameter space the TC2 model can enhance the production cross sections to several tens of fb and thus may be observable at the LHC due to rather…
We discuss a model which involves the top quark condensation and the walking technicolor. We focus on the scalar boson in such a model from the viewpoint of the observed scalar boson at the LHC.
In the framework of topcolor-assisted technicolor(TC2) model, there exist tree-level flavor-changing (FC) couplings which can result in the loop-level FC coupling $tcg$. Such $tcg$ coupling can contribute significant clues at the forthcoming Large Hadron Collider (LHC) experiments. In this paper, based on the TC2 model, we study some single t-quark production processes involving $tcg$ coupling at the Tevatron and LHC: $pp(p\bar{p})\to t\bar{q}(q=u,d,s),tg$. We calculate the cross sections of these processes. The results show that the cross sections at the Tevatron are too small to observe the …
Precision electroweak data, a light higgs and LHC searches for new spin one particles are all very constraining on technicolor models. We use a holographic model of walking techicolor (WTC) gauge dynamics, tuned to produce a light higgs and low $S$ parameter, to estimate the range of possible vector($ρ$) and pseudo-vector($A$) resonance masses and couplings as a function of the number of colours and the number of flavours of techni-singlet and techni-doublet quarks. The resulting models predict techni-hadron masses and couplings above the current limits from dilepton resonance searches at the …
We propose an interpretation for the ($l\bar lγγ,\ M_{γγ}=60{\rm GeV}$) events, which have recently been reported by L3 group at LEP. This may be a first signal of `Technicolor' theory.
The Tevatron experiments CDF and DO are close to making definitive statements about the technicolor discovery mode rho_T -> W pi_T for M(rho_T) <~ 230 GeV and M(pi_T) <~ 125 GeV. We propose new incisive tests for this mode and searches for others that may be feasible at the Tevatron and certainly are at the LHC. The other searches include two long discussed, namely, omega_T -> gamma pi_T and l+l-, and a new one -- for the I^G J^{PC} = 1^- 1^{++} partner, a_T, of the rho_T. Adopting the argument that the technicolor contribution to S is reduced if M(a_T) is near M(rho_T), we enumerate important…
We evaluate the top-quark FCNC productions induced by the topcolor assisted technicolor (TC2) model at the LHC. These productions proceed respectively through the parton-level processes g g -> t c_bar, c g->t, c g -> t g, c g -> t Z and c g -> t γ. We show the dependence of the production rates on the relevant TC2 parameters and compare the results with the predictions in the minimal supersymmetric model. We find that for each channel the TC2 model predicts a much larger production rate than the supersymmetric model. All these rare productions in the TC2 model can be enhanced above the 3-sigma…
Imagine to discover a new fourth family of leptons at the Large Hadron Collider (LHC) but no signs of an associated fourth family of quarks. What would that imply? An intriguing possibility is that the new fermions needed to compensate for the new leptons gauge anomalies simultaneously address the big hierarchy problem of the Standard Model. A natural way to accomplish such a scenario is to have the Higgs itself be composite of these new fermions. This is the setup we are going to investigate in this paper using as a template Minimal Walking Technicolor. We analyze a general heavy neutrino mas…
LHC searches for the standard model Higgs Boson in di-photon or di-tau decay modes place strong constraints on the light top-pion state predicted in technicolor models that include colored technifermions. Compared with the standard Higgs Boson, the top-pions have an enhanced production rate (largely because the technipion decay constant is smaller than the weak scale) and also enhanced branching ratios into di-photon and di-tau final states (largely due to the suppression of WW decays of the technipions). These factors combine to make the technipions more visible in both channels than a standa…
We discuss the strength of the trilinear Higgs boson coupling in technicolor (or composite) models in a model independent way. The coupling is determined as a function of a very general ansatz for the technicolor self-energy, and turns out to be equal or smaller than the one of the standard model Higgs boson depending on the dynamics of the theory. With this trilinear coupling we estimate the cross section for Higgs boson pair production at the LHC. This measurement is quite improbable in the case of a heavy standard model Higgs boson, but it will be even worse when this boson is dynamically g…
We construct an effective lagrangian for new strong interactions at the LHC, including as a first step the two lightest triplets of spin-1 resonances. Our parametrization is general enough to allow for previously unstudied spectrum and couplings. Among available frameworks to describe the spin-1 sector, we rely on an extra-dimensional description. Our approach limits the number of parameters, yet is versatile enough to describe the phenomenology of a wide range of new scenarios of strong electroweak symmetry breaking.
We use a holographic description of technicolor dynamics to study gauge theories that only break chiral symmetry when aided by a strong four fermion interaction. These Nambu-Jona-Lasinio (NJL) assisted technicolor models provide examples of different dynamics from walking technicolor which can, by tuning, generate a light higgs like $σ$ meson. We compute the vector meson ($ρ$) and axial vector meson (A) spectrum for a variety of models with techni-quarks in the fundamental representation, enlarging the available parameter space over a previous analysis of walking theories. These predictions de…
Under the assumption that the dijet excess seen by the CDF Collaboration near 150 Gev in Wjj production is due to the lightest technipion of the low-scale technicolor process $ρ_T \rightarrow W π_T$, we study its observability in LHC detectors with 1--20 inverse femtobarns of data. We describe interesting new kinematic tests that can provide independent confirmation of this LSTC hypothesis. We find that cuts similar to those employed by CDF, and recently by ATLAS, cannot confirm the dijet signal. We propose cuts tailored to the LSTC hypothesis and its backgrounds at the LHC that may reveal $ρ_…
A new particle at around 125 GeV has been observed at the LHC, which we show could be identified with the techni-dilaton (TD) predicted in the walking technicolor and thus should be an evidence of walking technicolor. The TD is a pseudo Nambu-Goldstone boson for the approximate scale symmetry spontaneously broken by techni-fermion condensation, with its lightness being ensured by the approximate scale invariance of the walking technicolor. We test the goodness-of-fit of the TD signatures using the presently available LHC data set, and show that the 125 GeV TD is actually favored by the current…
Conformal technicolor is a paradigm for new physics at LHC that may solve the problems of strong electroweak symmetry breaking for quark masses and precision electroweak data. We give explicit examples of conformal technicolor theories based on a QCD-like sector. We suggest a practical method to test the conformal dynamics of these theories on the lattice.
This paper extends an earlier one describing the Higgs boson $H$ as a light composite scalar in a strong extended technicolor model of electroweak symmetry breaking. The Higgs mass $M_H$ is made much smaller than $Λ_{ETC}$ by tuning the ETC coupling very close to the critical value for electroweak symmetry breaking. The technicolor interaction, neglected in the earlier paper, is considered here. Its weakness relative to extended technicolor is essential to understanding the lightness of $H$ compared to the low-lying spin-one technihadrons. Technicolor cannot be completely ignored, but implemen…
We perform a detailed study of the process of single color octet isoscalar $η_T$ production at the Tevatron with $η_T \to γ+ g$ decay signature, including a complete simulation of signal and background processes. We determined a set of optimal cuts from an analysis of the various kinematical distributions for the signal and backgrounds. As a result we show the exclusion and discovery limits on the $η_T$ mass which could be established at the Tevatron for some technicolor models.
The SM-like Higgs boson with mass of 125 GeV discovered at the LHC is subject to a natural interpretation of electroweak symmetry breaking. As a successful theory in offering this naturalness, technicolor with a scalar doublet and two both $SU(3)_c$ and $SU(N_{TC})$ colored scalars, which is considered as a low-energy effective theory, is proposed after the discovery of SM-like Higgs boson. At present status, the model can be consistent with both the direct and indirect experimental limits. In particular, the consistency with precision electroweak measurements is realized by the colored scalar…
Under the assumption that the dijet excess seen by the CDF Collaboration near 150 Gev in Wjj production is due to the lightest technipion of the low-scale technicolor process $ρ_T \rightarrow W π_T$, we study its observability in LHC detectors for 8 TeV collisions and 20 inverse femtobarns of integrated luminosity. We describe interesting new kinematic tests that can provide independent confirmation of this LSTC hypothesis. We show that cuts similar to those employed by CDF, and recently by ATLAS, cannot confirm the dijet signal. We propose cuts tailored to the LSTC hypothesis and its backgrou…
In this talk I argue that a light techni-dilaton exists in models of walking technicolor near the conformal window. The light techni-dilaton then mixes with the composite Higgs, which is predicted to be narrow and light in walking technicolor models. It is an interesting possibility that the newly discovered boson at LHC might be a mixed state of techni-dilaton and the composite Higgs.
We study the process p bar{p} --> gamma gamma gamma as a signal for associated photon-technipion production at the Tevatron. This is a clean signature with relatively low background. Resonant and non-resonant contributions are included and we show that technicolor models can be effectively probed in this mode.
Here I summarize some of the salient features of technicolor theories with technifermions in higher dimensional representations of the technicolor gauge group. The expected phase diagram as function of number of flavors and colors for the two index (anti)symmetric representation of the gauge group is reviewed. After having constructed the simplest walking technicolor theory one can show that it is not at odds with the precision measurements. The simplest theory also requires, for consistency, a fourth family of heavy leptons. The latter may result in an interesting signature at LHC. In the cas…
The ATLAS collaboration has recently reported an excess of about 2.5 $σ$ global significance at around 2 TeV in the diboson channel with the boson-tagged fat dijets, which may imply a new resonance beyond the standard model. We provide a possible explanation of the excess as the isospin-triplet technivector mesons (technirhos, denoted as $ρ_Π^{\pm,3}$) of the walking technicolor in the case of the one-family model as a benchmark. As the effective theory for the walking technicolor at the scales relevant to the LHC experiment, we take a scale-invariant version of the hidden local symmetry model…
Dark Matter candidates are natural in Technicolor theories. We introduce a general framework allowing to predict signals of Technicolor Dark Matter at colliders and set constraints from earth based experiments such as CDMS and XENON. We show that the associate production of the composite Higgs can lead to relevant signals at the Large Hadron Collider.
The technidilaton (TD) is a composite scalar predicted in walking technicolor (WTC), arising as a pseudo Nambu-Goldstone boson associated with the spontaneous breaking of the approximate scale invariance. Due to the Nambu-Goldstone boson's nature, the TD can be as light as the LHC boson that has been discovered at around 125 GeV. We discuss the size of the TD mass and the coupling properties relevant to the LHC study. It turns out that the TD couplings to the standard model (SM) particles take the same form as those of the SM Higgs boson, except the essentially distinguishable two ingredients:…
Strategies are presented for discovering light, color-singlet technipions (pi_T) produced in association with a vector boson through s-channel technirho production, at the Tevatron and LHC. Signal and W+jets background were simulated including detector effects. Tagging of b-quarks from the pi_T -> bb decay is found to be important to reduce the W+jets background. Kinematic properties of signal and background events are significantly different and simple cuts can be used to further improve the signal to background ratio.
We investigate theories in which the technifermions in higher dimensional representations of the technicolor gauge group dynamically break the electroweak symmetry of the standard model. For the two-index symmetric representation of the gauge group the lowest number of techniflavors needed to render the underlying gauge theory quasi conformal is two. We confront the models with the recent electroweak precision measurements and demonstrate that the two technicolor theory is a valid candidate for a dynamical breaking of the electroweak symmetry. The electroweak precision measurements provide use…
We focus on exclusive production of neutral technipion $\tilde π^0$ in $pp$ collisions at the LHC, i.e. on $p p \to p p \tilde π^0$ reaction. The dependence of the cross section on parameters of recently proposed vector-like Technicolor model is studied. Characteristic features of the differential distributions are discussed. For not too large technipion masses the diphoton decay channel has the dominant branching fraction. This is also the main reason for an enhanced production of neutral technipions in $γγ$-fusion reaction. We discuss potential backgrounds of the QCD and QED origin to the $p…
We discuss fermion mass generation in unified models where QCD and technicolor (or any two strongly interacting theories) have their Schwinger-Dyson equations coupled. In this case the technicolor (TC) and QCD self-energies are modified in comparison with the behavior observed in the isolated theories. In these models the pseudo-Goldstone boson masses are much higher than the ones obtained in different contexts, and phenomenological signals, except from a light scalar composite boson, will be quite difficult to be observed at present collider energies. The most noticeable fact of these models …
I briefly review the basic challenges and virtues of models breaking the electroweak symmetry dynamically. I will then introduce the (ultra) minimal walking technicolor models whose construction has been made possible thanks to recent progress in the understanding of the phase diagram for strongly coupled theories as function of number of flavors, colors and matter representation. I will mention possible relevant collider signatures. Interestingly, asymmetric Dark Matter is a natural possibility in our models providing interesting candidates for decaying Dark Matter models which have been expl…
We propose a "Higgs impostor" model for the 125 GeV boson, $X$, recently discovered at the LHC. It is a technipion, $η_T$, with $I^G J^{PC} = 0^- 0^{-+}$ expected in this mass region in low-scale technicolor. Its coupling to pairs of standard-model gauge bosons are dimension-five operators whose strengths are determined within the model. It is easy for the gluon fusion rate $σB(gg \to η_T \to γγ)$ to agree with the measured one, but $η_T \to ZZ^*,\,WW^*$ are greatly suppressed relative to the standard-model Higgs rates. This is a crucial test of our proposal. In this regard, we assess the most…
We propose an approach for the calculation of the yukawa coupling through the scalar decay constant and the chiral condensate in the context of the extended technicolor (ETC). We perform the nonperturbative computation of the yukawa coupling based on the improved ladder Schwinger-Dyson equation. It turns out that the yukawa coupling can be larger or smaller than the standard model (SM) value, depending on the number $N_D$ of the weak doublets for each technicolor (TC) index. It is thus nontrivial whether or not the huge enhancement of the production of the scalar via the gluon fusion takes pla…
We discuss a test of the Standard Model fermion mass origin in models of dynamical electroweak symmetry breaking. The couplings of composite pseudoscalar resonances to top quarks allow to distinguish high-scale Extended-Technicolor-type fermion mass generation from fermion partial compositeness and low-scale mass generation via an induced vacuum expectation value of a doublet coupled to the composite sector. These different possible origins of fermion masses are thus accessible via weak-scale physics searched for at the LHC.
We point out that the flavor problem in theories with dynamical electroweak symmetry breaking can be effectively decoupled if the physics above the TeV scale is strongly conformal, and the electroweak order parameter has a scaling dimension d = 1 + epsilon with epsilon \simeq 1/few. There are many restrictions on small values of epsilon: for epsilon << 1, electroweak symmetry breaking requires a fine-tuning similar to that of the standard model; large-N conformal field theories (including those obtained from the AdS/CFT correspondence) require fine-tuning for d < 2; `walking technicolor' theor…
I review the dynamical symmetry breaking (DSB) approach to the Origin of Mass, which is traced back to the original (2008 Nobel prize) work of Nambu based on the BCS analogue of superconductor where mass of nucleon (then elementary particle) arises due to Cooper paring and pions are provided as massless Nambu-Goldstone (NG) bosons, being composite as in Fermi-Yang/Sakata model. In this talk I will focus on the modern version of DSB or composite Higgs models: Walking/Conformal Technicolor, Hidden Local Symmetry (HLS) or Moose, and Top Quark Condensate, with the their extra dimension versions cl…
We quantify the rate and the signal-to-background ratio for Higgs --> b anti-b detection in double-diffractive events at the Tevatron and the LHC. The signal is predicted to be very small at the Tevatron, but observable at the LHC. We show that the double-diffractive dijet production may serve as a unique gluon factory. This process can be used also as a Pomeron-Pomeron luminosity monitor.
We discuss the production of W bosons in association with three jets at the LHC. We investigate how next-to-leading order QCD corrections modify basic kinematic distributions of jets and leptons. We also address the magnitude of NLO QCD effects in W+3 jet observables, relevant for SUSY searches at the LHC.
We study here the di-muon decay mode of a very light CP-odd Higgs boson of the NMSSM, a1, produced in association with a bottom-antibottom pair and find that, despite small event rates, a significant signal should be extractable from the SM background at the LHC with high luminosity.
We perform a detailed analyses of the CERN Large Hadron Collider (LHC) capability to discover first generation vector leptoquarks through their pair production. We study the leptoquark signals and backgrounds that give rise to final states containing a pair e+e- and jets. Our results show that the LHC will be able to discover vector leptoquarks with masses up to 1.3-2.1 TeV depending on their couplings to fermions and gluons.
The study of possible new physics signals in global event properties in pp collisions in full phase space and in rapidity intervals accessible at LHC is presented. The main characteristic is the presence of an elbow structure in final charged particle MD's in addition to the shoulder observed at lower c.m. energies.
We investigate the prospects for discovering the Flavour Changing Neutral Current (FCNC) $tqZ$ couplings via two production processes yielding trilepton signals: top quark pair production $pp\to t\bar{t}$ with one top decaying to the $Z$ boson and one light jet and the anomalous single top plus $Z$ boson production process $pp\to tZ$. We study these channels at various successors of the Large Hadron Collider~(LHC), i.e., the approved High-Luminosity LHC (HL-LHC) as well as the proposed High-Energy LHC~(HE-LHC) and Future Circular Collider in hadron-hadron mode (FCC-hh). We perform a full simul…
