Dr
Enrico Rinaldi
(RIKEN BNL Research Center)
7/23/18, 2:00 PM
Physics Beyond the Standard Model
Fundamental symmetry tests of baryon number violation in low-energy experiments can test beyond the Standard Model explanations of the matter-antimatter asymmetry of the universe.
Neutron-antineutron oscillations are predicted to be a signature of many baryogenesis mechanisms involving low-scale baryon number violation.
This work presents the first complete lattice quantum chromodynamics...
Jun-sik Yoo
(Stony Brook University)
7/23/18, 2:20 PM
Physics Beyond the Standard Model
Proton decay is one of possible signatures of baryon number violation, which has to exist to explain the baryon asymmetry and the existence of nuclear matter. Proton decays must be mediated through effective low-energy baryon number violating operators made of three quarks and a lepton. We calculate matrix elements of these operators between an initial proton and various final pseudoscalar...
Dr
Tanmoy Bhattacharya
(Los Alamos National Laboratory)
7/23/18, 2:40 PM
Physics Beyond the Standard Model
I will present an update on our calculations of nEDM due to the quark and gluon chromo-EDM operators, as well as the QCD Theta-term with which these mix. The calculations are being done by extrapolating to zero momentum transfer the F3 form factor of a vector current calculated using valence and disconnected Wilson-clover quarks on HISQ background configurations generate by the MILC collaboration.
Dr
Marco Garofalo
(INFN, unit of Rome Tor Vergata)
7/23/18, 3:00 PM
Physics Beyond the Standard Model
In this talk we present a numerical lattice study of a SU(3) gauge model where a SU(2) doublet of non-Abelian strongly interacting fermions is coupled to a complex scalar field doublet via a Yukawa and a Wilson-like term. Despite the presence of these two chiral breaking operators in the Lagrangian, the model enjoys an exact symmetry, acting on all fields, which prevents UV power divergent...
Prof.
Roberto Frezzotti
(University of Rome "Tor Vergata" and INFN unit of Rome Tor Vergata)
7/23/18, 3:20 PM
Physics Beyond the Standard Model
Numerical evidence for a new dynamical mechanism of elementary particle mass generation has been found by lattice simulation in a simplified SU(3) gauge model where a SU(2) doublet of strongly interacting fermions is coupled to a complex scalar field doublet via a Yukawa and a Wilson-like term.
We point out that if, as a next step towards the construction of a realistic...
Dr
Philipp Scior
(WWU Münster)
7/24/18, 2:00 PM
Physics Beyond the Standard Model
We present the results of a numerical investigation of SU(2) gauge theory with $N_f = 3/2$ flavours of fermions, corresponding to 3 Majorana fermions, which transform in the adjoint representation of the gauge group. At two values of the gauge coupling, the masses of bound states are considered as a function of the PCAC quark mass. The scaling of bound states masses indicates an infrared...
Dr
JONG-WAN Lee
(Pusan National University)
7/24/18, 2:20 PM
Physics Beyond the Standard Model
We report on the status of our program to simulate Sp(2N) gauge theories on the lattice. Motivated by the potential realization of SU(4)/Sp(4) ~ SO(6)/SO(5) composite Higgs model, we first consider Sp(4) theories with two Dirac fermion flavors in the fundamental representation. Preliminary results of meson spectrum will be presented along with discussion of the lattice systematics. Toward...
Nouman Butt
(Syracuse University)
7/24/18, 2:40 PM
Physics Beyond the Standard Model
We study a four dmensional lattice model comprising four reduced staggered fermions coupled to a scalar field through an SO(4) invariant interaction. Symmetries
of the lattice theory prohibit fermion mass terms. If we switch of the kinetic
term for the scalar field we obtain a model with a four fermion interaction which has been the focus of several recent lattice investigations. The results...
Prof.
Asit Kumar De
(Professor)
7/24/18, 3:00 PM
Physics Beyond the Standard Model
Proper treatment of redundant gauge degrees of freedom seems necessary for gauge theories with terms that explicitly break gauge symmetry (e.g., in chiral gauge theories with manifestly local formulation of lattice fermions) since these degrees of freedom become manifestly present in such theories. There is also a no-go theorem prohibiting use of BRST formalism in theories with compact gauge...
Mr
Mugdha Sarkar
(Saha Institute of Nuclear Physics)
7/24/18, 3:20 PM
Physics Beyond the Standard Model
Equivariant BRST (eBRST) SU(2) gauge theory involves gauge fixing in the SU(2)/U(1) coset space leaving the subgroup U(1) gauge invariant. This can be taken as an alternative formulation of SU(2) lattice gauge theory that uses gauge-fixing, evading the no-go theorem by Neuberger preventing the use of standard BRST. Results will be presented for our numerical simulation of the eBRST gauge...
Julius Kuti
(U.C. San Diego)
7/25/18, 2:00 PM
Physics Beyond the Standard Model
New results are discussed on the effective field theory of the light 0++ scalar in an important near-conformal strongly coupled BSM gauge theory and its lattice simulations in the sextet fermion representation. Relevant for the composite BSM Higgs, two distinct scenarios are introduced for the emergent light scalar as the composite σ-particle of chiral symmetry breaking or the dilaton of...
Dr
Chik Him Wong
(University of Wuppertal)
7/25/18, 2:20 PM
Physics Beyond the Standard Model
The light 0++ scalar can be probed for dilaton signatures in near-conformal gauge theories. A case study is presented for the analysis of the SU(3) gauge theory with two fermions in the two-index symmetric representation (sextet model). It is shown that statistical methods which are based on Bayesian Markov Chain Monte Carlo analysis are important for robust tests of dilaton fingerprints in...
Dr
Kieran Holland
(University of the Pacific)
7/25/18, 2:40 PM
Physics Beyond the Standard Model
There is a long running controversy over which SU(3) gauge theories with Nf massless fermion flavors in the fundamental representation are conformal, with particular focus on Nf = 12 and 10. In our studies of both theories, we have found no evidence of conformality as shown by an infrared fixed point of the beta function, in direct contradiction to claims by other groups covering the same...
Prof.
Daniel Nogradi
(Eotvos University Budapest - Universidad Autonoma Madrid)
7/25/18, 3:00 PM
Physics Beyond the Standard Model
We report new results on the beta-function of an important BSM gauge
theory with ten massless fermion flavors in the fundamental
representation of the SU(3) color gauge group. The existence of an
infrared fixed point (IRFP) was reported in [PoS LATTICE2016 (2017) 228] at $g^2 \sim 7.0$ of the renormalized gauge coupling. We find a positive and rapidly increasing beta-function in the...
Dr
Mohamed Anber
(Lewis & Clark College)
7/25/18, 3:20 PM
Physics Beyond the Standard Model
I use the traditional and more recently discovered 1-form discrete 't Hooft anomaly matching conditions and propose a novel realization of the symmetries of SU(2) Yang-Mills theory with two massless adjoint Weyl fermions in the strongly-coupled regime. The theory has a spectrum identical to the one obtained by compactifying it on a small circle. This offers a new perspective on the lattice...
Claudio Rebbi
7/26/18, 11:00 AM
Physics Beyond the Standard Model
In lattice simulations one generally projects correlators over zero
spatial momentum to calculate masses and related spectral data. The sum over space lattice points, however, discards information which may be useful especially in the calculation of disconnected diagrams. I will show that, by using momentum conservation, the calculation of non-zero momentum components of disconnected...
Prof.
Maarten Golterman
(San Francisco State University)
7/26/18, 11:20 AM
Physics Beyond the Standard Model
We apply a recently developed dilaton-pion effective field theory for
asymptotically free gauge theories near the conformal window to the SU(3)
gauge theory with $N_f=8$ fermions in the fundamental representation.
Numerical data for this theory suggests the existence of a large-mass
regime, where the fermion mass is not small but nevertheless the effective
theory is applicable because of...
Thomas DeGrand
(University of Colorado)
7/26/18, 11:40 AM
Physics Beyond the Standard Model
Some recent beyond Standard Model phenomenology is based on new strongly interacting dynamics
of SU(N) gauge fields coupled to various numbers of fermions. When N=3 these systems are
analogues of QCD, although the fermion masses are typically different from the ones of real world QCD.
Many quantities needed for phenomenology from these
models have been computed on the lattice. We are...
Prof.
Ethan Neil
(University of Colorado, Boulder)
7/26/18, 12:00 PM
Physics Beyond the Standard Model
I present updated spectroscopy results from the LSD collaboration on
SU(3) gauge theory with $N_f=8$ degenerate fermions in the fundamental
representation, using nHYP-smeared staggered fermions. The new results
include added statistics, a more sophisticated systematic error analysis,
and the use of joint fits to stabilize estimates of the $0^{++}$ scalar
meson mass. We find persistent...
Mr
William Jay
(University of Colorado Boulder)
7/26/18, 12:20 PM
Physics Beyond the Standard Model
We describe our recent lattice study of the baryon spectrum of SU(4) gauge theory with fully dynamical Wilson-clover fermions in the fundamental and sextet representations. This system is closely related to a model of physics beyond the Standard Model containing a composite Higgs. The model also contains a partially composite top quark, which mixes linearly with a new baryon of SU(4)...
Mr
Diego Silva
(The University of Iowa)
7/26/18, 12:40 PM
Physics Beyond the Standard Model
A SU(3) gauge theory with 12 flavors is a model of great interest for beyond the standard model physics. Running RHMC simulations for different masses and betas we study the Fisher zeroes in the vicinity of the endpoint of a line of first order transitions. The pinching of these zeros with respect to increasing volume provide information about a possible unconventional continuum limit. We also...
Mr
Sajid Ali
(Institute for Theoretical Physics, University of Münster, Germany.)
7/27/18, 4:30 PM
Physics Beyond the Standard Model
In $\mathcal{N} = 1$ supersymmetric Yang-Mills theory the superpartner of the gluon is the gluino, which is a spin 1/2 Majorana particle in the adjoint representation of the gauge group. Combining three gluinos, it is possible to form colour neutral bound states, analogous to baryons in QCD. The correlation functions of the corresponding baryonic operators contain a contribution represented by...
Mr
Henning Gerber
(WWU Münster)
7/27/18, 4:50 PM
Physics Beyond the Standard Model
We summarise the current status of our numerical simulations of N = 1
supersymmetric Yang-Mills theory with gauge group SU(3). We use the
formulation of Curci and Veneziano with clover-improved Wilson fermions.
The masses of various bound states have been obtained at different
values of the gluino mass and gauge coupling. Extrapolations to the
limit of vanishing gluino mass indicate that...
Dr
Georg Bergner
(Friedrich-Schiller-Universität Jena, WWU Münster)
7/27/18, 5:10 PM
Physics Beyond the Standard Model
This talk is an overview of our recent investigations of supersymmetric and near conformal gauge theories. We have studied extensively $\mathcal{N}=1$ super Yang-Mills theory, most recently with the gauge group SU(3). In addition we have investigated theories that show indications for a conformal behaviour with an infrared fixed point. More recently we have included a mixed fundamental and...
Dr
Björn Wellegehausen
(FSU Jena)
7/27/18, 5:30 PM
Physics Beyond the Standard Model
$\mathcal{N}=1$ Supersymmetric QCD (SQCD) is a possible building block of theories beyond the standard model. It describes the interaction between gluons and quarks with their superpartners, gluinos and squarks. Since supersymmetry is
explicitly broken by the lattice regularization, a careful fine-tuning of operators is necessary to obtain a supersymmetric continuum limit. For the pure gauge...
Mr
Marc Steinhauser
(Friedrich Schiller University Jena)
7/27/18, 5:50 PM
Physics Beyond the Standard Model
Supersymmetric gauge theories are a popular building block of theories beyond the standard model. We investigate the pure gauge sector of Super-QCD focusing on the bound states, i.e. mesonic gluinoballs, gluino-glueballs and pure glueballs. To improve chiral symmetry as well as supersymmetry at finite lattice spacing, we introduce a deformed Super-Yang-Mills lattice action. It contains a twist...
Camilo Lopez
(University of Jena)
7/27/18, 6:10 PM
Physics Beyond the Standard Model
Composite operators of bare fermion fields evolved along a trajectory on field space by means of flow equations get renormalised multiplicatively. Therefore, even in the case of Wilson fermions, the renormalization of expectation values of fermion operators can be simplified drastically on the lattice. We measure the gluino condensate in N=1 supersymmetric Yang-Mills theory at non-zero...