scholarly journals NEW BOUND STATES OF HEAVY QUARKS AT LHC AND TEVATRON

2011 ◽  
Vol 26 (15) ◽  
pp. 2503-2521 ◽  
Author(s):  
C. R. DAS ◽  
C. D. FROGGATT ◽  
L. V. LAPERASHVILI ◽  
H. B. NIELSEN
Keyword(s):  
Top Quark ◽  
Bound States ◽  
Form Factors ◽  
Top Quarks ◽  
Bound State ◽  
Heavy Quarks ◽  
Fourth Generation ◽  
Charge Multiplicity ◽  
The Masses ◽  
B Quark

The present paper is based on the assumption that heavy quarks bound states exist in the Standard Model (SM). Considering New Bound States (NBS) of top–antitop quarks (named T-balls) we have shown that: (1) there exists the scalar 1S-bound state of [Formula: see text]; (2) the forces which bind the top-quarks are very strong and almost completely compensate the mass of the twelve top–antitop-quarks in the scalar NBS; (3) such strong forces are produced by the Higgs–top-quarks interaction with a large value of the top-quark Yukawa coupling constant gt≃1. Theory also predicts the existence of the NBS [Formula: see text], which is a color triplet and a fermion similar to the t'-quark of the fourth generation. We have also considered the "b-quark-replaced" NBS, estimated the masses of the lightest fermionic NBS: M NBS ≳300 GeV , and discussed the larger masses of T-balls. We have developed a theory of the scalar T-ball's condensate and predicted the existence of three SM phases. Searching for heavy quark bound states at the Tevatron and LHC is discussed. We have constructed the possible form-factors of T-balls, and estimated the charge multiplicity coming from the T-ball's decays.

scholarly journals Bound State of Heavy Quarks Using a General Polynomial Potential

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Hesham Mansour ◽  
Ahmed Gamal
Keyword(s):  
Bound States ◽  
Bound State ◽  
Heavy Quarks ◽  
Polynomial Potential ◽  
Schrödinger’S Equation ◽  
General Polynomial ◽  
L Value ◽  
Schrödinger's Equation ◽  
Better Than ◽  
Good Agreement

In the present work, the mass spectra of the bound states of heavy quarks cc-,bb-, and Bc meson are studied within the framework of the nonrelativistic Schrödinger’s equation. First, we solve Schrödinger’s equation with a general polynomial potential by Nikiforov-Uvarov (NU) method. The energy eigenvalues for any L- value is presented for a special case of the potential. The results obtained are in good agreement with the experimental data and are better than previous theoretical studies.

SEARCH FOR SINGLE TOP QUARK PRODUCTION AT DØ

2006 ◽  
Vol 21 (17) ◽  
pp. 1339-1353
Author(s):  
REINHARD SCHWIENHORST
Keyword(s):  
Cross Section ◽  
Top Quark ◽  
Production Cross ◽  
Top Quarks ◽  
Event Analysis ◽  
Proton Antiproton ◽  
Single Top ◽  
Top Quark Production ◽  
Quark Production ◽  
B Quark

We present a review of searches for electroweak production of single top quarks at the Fermilab Tevatron proton–antiproton collider at [Formula: see text]. Searches for s-channel and t-channel single top quark production have been carried out using secondary-vertex b-quark tagging and advanced event analysis methods in order to maximize the sensitivity to single top quark production. So far, no evidence for a single top quark signal has been found. However, 95% confidence level upper limits on the production cross-section have been set that improve upon previous limits by factors of two to three and are approaching the cross-section region predicted by the standard model.

scholarly journals Using the Beth–Uhlenbeck Approach to Describe the Kaon to Pion Ratio in a 2 + 1 Flavor PNJL Model

Particles ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 169-177
Author(s):  
David Blaschke ◽  
Alexandra Friesen ◽  
Yuri Kalinovsky ◽  
Andrey Radzhabov
Keyword(s):  
Experimental Data ◽  
Bound States ◽  
Bound State ◽  
Phase Shifts ◽  
Low Energy ◽  
K Channel ◽  
Energy Mode ◽  
Pnjl Model ◽  
The Masses ◽  
Comparison With Experimental Data

The kaon to pion ratios are discussed in the framework of a 2 + 1 flavor PNJL model. In order to interpret the behavior of bound states in medium, the Beth–Uhlenbeck approach is used. It is shown that, in terms of phase shifts in the K + channel, an additional low-energy mode could appear as a bound state in medium, since the masses of the quark constituents are different. The comparison with experimental data for the ratios is performed and the influence of the anomalous mode to the “horn” effect in the K + / π + ratio is discussed.

scholarly journals MINIMAL ELECTROWEAK SYMMETRY BREAKING MODEL IN EXTRA DIMENSIONS

2001 ◽  
Vol 16 (supp01c) ◽  
pp. 937-939 ◽  
Author(s):  
HSIN-CHIA CHENG
Keyword(s):  
Top Quark ◽  
Quark Mass ◽  
Bound States ◽  
Higgs Field ◽  
Bound State ◽  
Boson Mass ◽  
Electroweak Symmetry ◽  
Top Quark Mass ◽  
Composite Higgs ◽  
Renormalization Group Equations

We show that if the Standard Model gauge fields and fermions propagate in extra dimenions, a composite Higgs field with the correct quantum number can arise naturally as a bound state due to the strong gauge interactions in higher dimensions. The top quark mass and the Higgs mass can be predicted from the infrared fixed points of the renormalization group equations. The top quark mass is in good agreement with the experimental value, and the Higgs boson mass is predicted to be ~ 200GeV. There may be some other light bound states which could be observed at upcoming collider experiments.

scholarly journals Simple mass estimates for resonance(s) being 6 top + 6 antitop bound states and combinations thereof

2016 ◽  
Vol 31 (32) ◽  
pp. 1650168 ◽  
Author(s):  
H. B. Nielsen
Keyword(s):  
Bound States ◽  
Yukawa Potential ◽  
Simple Calculation ◽  
Bound State ◽  
New Physics ◽  
Step Function ◽  
Multiple Point ◽  
Fundamental Particles ◽  
Simple Mass ◽  
The Masses

We have long speculated,[Formula: see text] that 6 top + 6 antitop quarks due to the relatively large size of the top-Yukawa coupling would bind exceptionally strongly by mainly Higgs exchange. Here we present a surprisingly simple “calculation” of the mass of this speculated bound state. Even a possible resonance in scattering of two such bound states is speculated. For the “calculation” of the masses it is crucial to assume, that our since long speculated principle “multiple point principle,”[Formula: see text] is true. This principle says: there are several vacua all having almost zero energy density. Further, we make an approximation of the Higgs Yukawa potential essentially replacing the exponential in it by a step-function. The new result means that there are now two independent calls for our bound state having the mass around 750 GeV required by our “new law of nature” the Multiple Point Principle. It should be remarked that in our picture there is no new physics in the sense of new fundamental particles, but the “multiple point principle” is new in the sense of being not yet accepted. Further, we get the same mass within uncertainties as earlier2 but now from a completely different assumption, except for being from our “multiple point principle.” But the two masses are gotten from using different (speculative) vacua occurring in the pure Standard Model.

scholarly journals Diphoton decay of the Higgs boson and new bound states of top and antitop quarks

2015 ◽  
Vol 30 (21) ◽  
pp. 1550132 ◽  
Author(s):  
C. D. Froggatt ◽  
C. R. Das ◽  
L. V. Laperashvili ◽  
H. B. Nielsen
Keyword(s):  
Higgs Boson ◽  
Excited States ◽  
Atomic Physics ◽  
Bound States ◽  
Gluon Fusion ◽  
Top Quarks ◽  
Bound State ◽  
Sigma Level ◽  
Gluon Production ◽  
State Formula

We consider the constraints, provided by the LHC results on Higgs boson decay into 2 photons and its production via gluon fusion, on the previously proposed Standard Model (SM) strongly bound state S of six top quarks and six antitop quarks. A correlation is predicted between the ratios [Formula: see text] and [Formula: see text] of the Higgs diphoton decay and gluon production amplitudes, respectively to their SM values. We estimate the contribution to these amplitudes from one-loop diagrams involving the 12 quark bound state S and related excited states using an atomic physics based model. We find two regions of parameter space consistent with the ATLAS and CMS data on [Formula: see text] at the three sigma level: a region close to the SM values [Formula: see text] with the mass of the bound state [Formula: see text][Formula: see text]GeV and a region with [Formula: see text] corresponding to a bound state mass of [Formula: see text][Formula: see text]GeV.

scholarly journals DECAYS OF FOURTH GENERATION BOUND STATES

2012 ◽  
Vol 27 (30) ◽  
pp. 1250179
Author(s):  
V. F. DMITRIEV ◽  
V. V. FLAMBAUM
Keyword(s):  
Higgs Boson ◽  
Binding Energy ◽  
Decay Mode ◽  
Bound States ◽  
Bound State ◽  
Fourth Generation ◽  
Exchange Potential ◽  
Total Width ◽  
Decay Modes ◽  
Boson Exchange

We consider the decay modes of the heavy [Formula: see text] bound states originating from Higgs boson exchange between quark–antiquark pair. In case of a small coupling between the fourth and lower generation the main decay mode is [Formula: see text] annihilation. We show that for a vector state the dominant decay modes are Higgs-gamma and Higgs-Z decays, while for a pseudoscalar state the strong two-gluon decay mode dominates. The bound states are very narrow. The ratio of the total width to the binding energy is less than 1% if we are not extremely close to the critical quark mass where the binding energy is very small. The discussed decay modes exist for any fermion–antifermion bound states including heavy leptons and heavy neutrinos if their masses are high enough to form a bound state due to attractive Higgs boson exchange potential.

scholarly journals ZH production in gluon fusion: two-loop amplitudes with full top quark mass dependence

2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Long Chen ◽  
Gudrun Heinrich ◽  
Stephen P. Jones ◽  
Matthias Kerner ◽  
Jonas Klappert ◽  
...  
Keyword(s):  
Top Quark ◽  
Quark Mass ◽  
Gluon Fusion ◽  
Top Quarks ◽  
Mass Dependence ◽  
Finite Part ◽  
Top Quark Mass ◽  
Helicity Amplitudes ◽  
Quark Mass Dependence ◽  
Loop Amplitudes

Abstract We present results for the two-loop helicity amplitudes entering the NLO QCD corrections to the production of a Higgs boson in association with a Z -boson in gluon fusion. The two-loop integrals, involving massive top quarks, are calculated numerically. Results for the interference of the finite part of the two-loop amplitudes with the Born amplitude are shown as a function of the two kinematic invariants on which the amplitudes depend.

scholarly journals Effective Scalar Potential in Asymptotically Safe Quantum Gravity

Universe ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 45
Author(s):  
Christof Wetterich
Keyword(s):  
Quantum Gravity ◽  
Top Quark ◽  
Particle Physics ◽  
Scalar Potential ◽  
Scalar Fields ◽  
The Standard Model ◽  
Scaling Potential ◽  
Realistic Description ◽  
The Masses ◽  
Dynamical Dark Energy

We compute the effective potential for scalar fields in asymptotically safe quantum gravity. A scaling potential and other scaling functions generalize the fixed point values of renormalizable couplings. The scaling potential takes a non-polynomial form, approaching typically a constant for large values of scalar fields. Spontaneous symmetry breaking may be induced by non-vanishing gauge couplings. We strengthen the arguments for a prediction of the ratio between the masses of the top quark and the Higgs boson. Higgs inflation in the standard model is unlikely to be compatible with asymptotic safety. Scaling solutions with vanishing relevant parameters can be sufficient for a realistic description of particle physics and cosmology, leading to an asymptotically vanishing “cosmological constant” or dynamical dark energy.

scholarly journals Bs → Kℓv form factors with 2+1 flavors

2018 ◽  
Vol 175 ◽  
pp. 13008 ◽  
Author(s):  
Yuzhi Liu ◽  
Jon A. Bailey ◽  
A. Bazavov ◽  
C. Bernard ◽  
C. M. Bouchard ◽  
...  
Keyword(s):  
Quark Mass ◽  
Strange Quark ◽  
Lattice Spacing ◽  
Light Quark ◽  
Form Factors ◽  
Ckm Matrix ◽  
Strange Quark Mass ◽  
Light Quark Mass ◽  
B Quark

Using the MILC 2+1 flavor asqtad quark action ensembles, we are calculating the form factors f0 and f+ for the semileptonic Bs → Kℓv decay. A total of six ensembles with lattice spacing from ≈ 0.12 to 0.06 fm are being used. At the coarsest and finest lattice spacings, the light quark mass m’l is one-tenth the strange quark mass m’s. At the intermediate lattice spacing, the ratio m’l/m’s ranges from 0.05 to 0.2. The valence b quark is treated using the Sheikholeslami-Wohlert Wilson-clover action with the Fermilab interpretation. The other valence quarks use the asqtad action. When combined with (future) measurements from the LHCb and Belle II experiments, these calculations will provide an alternate determination of the CKM matrix element |Vub|.

Sign in / Sign up

Export Citation Format

Share Document