We present new results on the thermal production yield of a hypothetical state made of six quarks uuddss assuming its production in heavy-ion collisions at the CERN Large Hadron Collider (LHC). A state with this quark content and mass low enough to be stable against decay in timescales of the order of the age of the Universe has been hypothesized by one of us (G. Farrar) and has been discussed as a

We evaluate the stellar energy-loss rates 𝒬 due to the production of neutrino pair in 3-3-1 models. The energy loss rate 𝒬 is evaluated for different values of β=±13,±23,±3 in which β is a parameter used to define the charge operator in the 331 models. We show that the contribution of dipole moment to the energy loss rate is small compared to the contribution of new natural gauge boson Z′. The correction

Starting from noncommutative Fermi theory in two dimensions, we construct a deformed Kac–Moody algebra between its vector and chiral currents. The higher-order corrections to the deformed Kac–Moody algebra are explicitly calculated. We observe that the ordinary Schwinger terms are not affected by noncommutativity. Finally we conclude that the deformed Kac–Moody algebra can be given in term of ordinary

A strongly coupled Quark–Gluon Plasma (sQGP) is created in the high-energy heavy-ion collisions at Relativistic Heavy-Ion Collider (RHIC) and Large Hadron Collider (LHC). Our present understanding of sQGP as a very good liquid with astonishingly low viscosity is reviewed. With the arrival of the interesting results from LHC in high-energy p+p and p+A, a new endeavor to characterize the transition from

This work is to introduce a new kind of modified gravitational theory, named as f(ℛ,𝒢,𝒯) (also f(ℛ,𝒯,𝒢)) gravity, where ℛ is the Ricci scalar, 𝒢 is Gauss–Bonnet invariant and 𝒯 is the trace of the energy–momentum tensor. With the help of different models in this gravity, we investigate some physical features of different relativistic compact stars. For this purpose, we develop the effectively

When discussing consequences of symmetries of dynamical systems based on Noether’s first theorem, most standard textbooks on classical or quantum mechanics present a conclusion stating that a global continuous Lie symmetry implies the existence of a time-independent conserved Noether charge which is the generator of the action on phase space of that symmetry, and which necessarily must as well commute

We calculate bounds for the branching ratio of the Bs0→τe decay, for the first time, in the context of flavor changing neutral currents mediated by a Z′ gauge boson, which can arise from five extended models. In this sense, by using experimental measurements on the B→Xsγ decay and the Bs0→μ+μ− process, we look for constraints of the Z′bs coupling, where the more restrictive bound is offered by the

We extend a classically scale invariant model where the electroweak symmetry breaking is triggered by the dynamical chiral symmetry breaking in a hidden QCD sector, and a real singlet scalar S mediates these two sectors. Our model can explain cosmic inflation without unitarity violation in addition. Slow-roll inflation occurs along a valley in scalar potential. In the original model, the coupling −λHS

The time dependence of the temperature during the reheating process is studied. We consider the thermal feedback effects of the produced particles on the effective dissipation rate of the inflaton field, which can lead to enhanced production of particles. We parameterize the temperature dependence of the dissipation rate in terms of a Taylor expansion containing the vacuum decay rate and the thermal

In this paper, the mass spectra of mesons with one or two heavy quarks and their diquarks partners are estimated within a nonrelativistic framework by solving Schrödinger equation with an effective potential inspired by a symmetry preserving Poincaré covariant vector–vector contact interaction model of quantum chromodynamics. Matrix Numerov method is implemented for this purpose. In our survey of mesons

In this paper, the versions of quantum electrodynamics (QED) with spinors in fermion equations are briefly examined. In the new variants of the theory, the concept of vacuum polarization is unnecessary. The new content of fermion vacuum (without the Dirac sea) in the examined versions of QED leads to new physical consequences, part of which can be tested experimentally in the future.

The ℤ2×ℤ2 heterotic string orbifold yielded a large space of phenomenological three generation models and serves as a testing ground to explore how the Standard Model of particle physics may be incorporated in a theory of quantum gravity. In this paper, we explore the existence of type 0 models in this class of string compactifications. We demonstrate the existence of type 0 ℤ2×ℤ2 heterotic string

Based on the supersymmetry structures, we propose to solve the model of a charged Dirac oscillator interacting with a uniform perpendicular magnetic field on both commutative and noncommutative planes in a unified way by employing unitary transformations. The unitary operators are constructed out of the generators of the supersymmetry structures of the model.

The supersymmetric Lee–Yang model is arguably the simplest interacting supersymmetric field theory in two dimensions, albeit nonunitary. A natural question is if there is an analogue of supersymmetric Lee–Yang fixed point in higher dimensions. The absence of any ℤ2 symmetry (except for fermion numbers) makes it impossible to approach it by using perturbative 𝜖 expansions. We find that the truncated

Analyticity and crossing properties of four-point function are investigated in conformal field theories in the frameworks of Wightman axioms. A Hermitian scalar conformal field, satisfying the Wightman axioms, is considered. The crucial role of microcausality in deriving analyticity domains is discussed and domains of analyticity are presented. A pair of permuted Wightman functions are envisaged. The

In this paper, we consider the effects of bound atomic electrons scattered by solar neutrinos due to the electromagnetic properties of neutrinos. This necessitates considering the recoil of atomic nucleus, which should be considered in the momentum conservation, but the effect to the energy conservation is negligible. This effect changes the kinematic behavior of the scattered electron compared to

Experimental collaborations for the large hadron collider conducted various searches for supersymmetry. In the absence of signals, lower limits were put on sparticle masses but usually within frameworks with (over-)simplifications relative to the entire indications by supersymmetry models. For complementing current interpretations of experimental bounds, we introduce a 30-parameter version of the R-parity

In this work we construct metrics corresponding to radiating black holes whose near horizon regions cannot be approximated by Rindler space–time. We first construct infinite parameter coordinate transformations from Minkowski coordinates, such that an observer using these coordinates to describe space–time events measures the Minkowski vacuum to be Planckian. Utilizing these results, we construct a

In the system of a pair of quantum-entangled neutral kaons from meson decays, when one kaon collapses into the KS state, the other will collapse instantaneously into the KL state, due to entanglement and nonlocality. However, if the alternative hypothesis is correct and there is a time window during which one kaon is unaware that the other has decayed, some quantum mechanically prohibited KSKS decays

This paper analyses the algebraic and physical properties of the spin and orbital angular momenta of light in the quantum mechanical framework. The consequences of the fact that these are not angular momenta in the quantum mechanical sense are worked out in mathematical detail. It turns out that the spin part of the angular momentum has continuous eigenvalues. Particular attention is given to the paraxial

This work studies the theoretical construction of charged quintessence thin-shell wormholes using Israel thin-shell approach. The stability of these wormhole solutions is investigated by taking linear, logarithmic and Chaplygin gas models as a constituent of exotic matter at thin-shell. The presence of wormhole stability regions particularly relies on the physically justifiable values of charge and

A strongly coupled Quark–Gluon Plasma (sQGP) is created in the high-energy heavy-ion collisions at Relativistic Heavy-Ion Collider (RHIC) and Large Hadron Collider (LHC). Our present understanding of sQGP as a very good liquid with astonishingly low viscosity is reviewed. With the arrival of the interesting results from LHC in high-energy p+p and p+A, a new endeavor to characterize the transition from

Analyticity and crossing properties of four-point function are investigated in conformal field theories in the frameworks of Wightman axioms. A Hermitian scalar conformal field, satisfying the Wightman axioms, is considered. The crucial role of microcausality in deriving analyticity domains is discussed and domains of analyticity are presented. A pair of permuted Wightman functions are envisaged. The

In this paper, we consider the effects of bound atomic electrons scattered by solar neutrinos due to the electromagnetic properties of neutrinos. This necessitates considering the recoil of atomic nucleus, which should be considered in the momentum conservation, but the effect to the energy conservation is negligible. This effect changes the kinematic behavior of the scattered electron compared to

We calculate bounds for the branching ratio of the Bs0→τe decay, for the first time, in the context of flavor changing neutral currents mediated by a Z′ gauge boson, which can arise from five extended models. In this sense, by using experimental measurements on the B→Xsγ decay and the Bs0→μ+μ− process, we look for constraints of the Z′bs coupling, where the more restrictive bound is offered by the

We extend a classically scale invariant model where the electroweak symmetry breaking is triggered by the dynamical chiral symmetry breaking in a hidden QCD sector, and a real singlet scalar S mediates these two sectors. Our model can explain cosmic inflation without unitarity violation in addition. Slow-roll inflation occurs along a valley in scalar potential. In the original model, the coupling −λHS

The time dependence of the temperature during the reheating process is studied. We consider the thermal feedback effects of the produced particles on the effective dissipation rate of the inflaton field, which can lead to enhanced production of particles. We parameterize the temperature dependence of the dissipation rate in terms of a Taylor expansion containing the vacuum decay rate and the thermal

Composite nature of a particle can be probed by electromagnetic interactions and information about their structure is embedded in form factors. Most of the experimental and theoretical efforts on baryon electromagnetic form factors have been focused on nucleon while the data on charmed sector are limited to spectroscopy, and weak and strong decays. Forthcoming experiments with a heavy-hadron physics

We revise the steady vortex surface theory following the recent finding of asymmetric vortex sheets (Migdal, 2021). These surfaces avoid the Kelvin–Helmholtz instability by adjusting their discontinuity and shape. The vorticity collapses to the sheet only in an exceptional case considered long ago by Burgers and Townsend, where it decays as a Gaussian on both sides of the sheet. In generic asymmetric

This paper reviews a systematic dynamical analysis on a general form of scalar field as Dark Energy (DE) with dark matter (DM) to sort out the “cosmic coincidence” problem. Here the autonomous system of differential equations is two-dimensional (2D) as well as nonlinear. So we have utilized nonlinear dynamical theory to explain various cosmological implications of this model. Nowadays, we have noted

We study the fluctuations in the brightness temperature of 21-cm signal δT21 at the dark ages (z∼100) with a dark matter (DM) candidate in Inert Doublet Model (IDM). We then explore the effects of different fractions of IDM DM on δT21 signal. The IDM DM masses are chosen in few tens of GeV region as well as in the high mass region beyond 500 GeV. It has been observed that the δT21 signal is more sensitive

In this paper, we study consequences of the assumption that the gauge group SU(2) of the standard model is a nonassociative image of Spin(3). Such an approach allows us to take a different look at the Higgs mechanism and obtain the value of the Weinberg angle in very good agreement with the experiment.

Following a field-theoretical approach, we study the scalar Casimir effect upon a perfectly conducting cylindrical shell in the presence of spontaneous Lorentz symmetry breaking. The scalar field is modeled by a Lorentz-breaking extension of the theory for a real scalar quantum field in the bulk regions. The corresponding Green’s functions satisfying Dirichlet boundary conditions on the cylindrical

In this paper, we consider the local topological structures of a class of new worldsheets, call it the rectifying worldsheets, which are generated by a class of singular worldlines. Using the classification approaches of the finite type on the tangent developables and defining the extended striction curve, this paper gives the detailed classification of the rectifying worldsheets of singular worldlines

CEPC has two MDI locations. It is very complex in the mechanics design owing to extremely high precision and stability requirement as well as the limited space. This paper will describe two most complex mechanics issues and the progress. For the vacuum connection between detector and accelerator, two schemes including RVC and inflatable seal have been designed in detail. For the cryostat support system

Since the first idea of a collider was patented by Rolf Wideröe (1902–1996) in 1943 and the first e+e− circular collider, AdA, was successfully principle-proved in LAL, Orsay, France in 1963, different kinds of colliders have been built in the past and planned for the future. In this paper, we will make a rather complete and brief review of the history of different colliders and give a perspective

In this paper, we give preliminary designs of beam polarization manipulations by inserting three different types of insertions in the Circular Electron–Positron Collider (CEPC) at center-of-mass energies of 91 GeV (Z-pole). With the wigglers in the collider ring, we can obtain 5% transverse polarization in 1.1 h for the precise energy measurement. To overcome depolarization effects as the beam energy

Radio frequency (RF) parameters design is an important part in RF system design. In this paper we will introduce a general method of choosing appropriate RF parameters for a circular e+e− collider. The RF parameters are determined with several analytical formulas. With this method, the RF parameters of the Circular Electron–Positron Collider (CEPC) for Conceptual Design Report (CDR) are verified. A

In November 2018, CEPC CDR was announced and since then, CEPC accelerator entered TDR phase towards its planned completion at the end of 2022. In this paper, we give status review of CEPC optimization design, hardware TDR R&D progresses, CEPC-SppC compatibility relation, civil engineering design, site selection, CIPC and international collaborations, etc. CEPC plan is also presented.

A damping ring system which includes a small 1.1 GeV ring and two transport lines is introduced in CEPC linac in order to reduce the transverse emittance of positron beam at the end of linac and hence reduce the beam loss in the booster. This paper introduces the parameter choice and optics study of damping ring. The corresponding instability effect and IBS effect are also checked to make sure the

To obtain high luminosity, compact high gradient quadrupole magnets QD0 and QF1 are required on both sides of the interaction points of the proposed Circular Electron Positron Collider (CEPC). QD0 is a double aperture superconducting quadrupole closest to the interaction point with a crossing angle between two aperture centerlines of 33 mrad. Magnetic field crosstalk between two apertures of QD0 is

The CEPC booster will accelerate the e−e+ beam from 10 GeV to 120 GeV, so the field of the dipole magnets will change with the beam energy, of which the minimal working field is 29 Gs whereas the maximal field is 338 Gs. To reach the requirement of high precision at lower field level, three kinds of new dipole magnets are proposed and studied. To test and verify the designs of the magnets, two subscale

A Circular Electron Positron Collider (CEPC) with a circumference of about 100 km and a beam energy up to 120 GeV is proposed to be constructed in China. Over 80% of the collider ring is covered by conventional magnets. Most dipole and quadrupole magnets are twin aperture magnets with an inter-beam separation of 350 mm. Two 1-meter-long twin aperture prototype magnets are designed and manufactured

An analytical magnetic field expression for a circular vacuum chamber with induced eddy on it is obtained. Two boundary conditions are discussed: with and without the iron poles; the former implies the use of the image current methods. After the current angular distribution in the vacuum chamber is calculated, a contour integration is applied to obtain the field distribution in the aperture. The application

The beam power of the CEPC Collider is about 60 MW, so an efficiency of an RF power source is very important for cost of project implementation. The most popular source for an accelerator is a klystron, which has the advantage that it can be operated at high power with a reasonable high efficiency. IHEP is developing 650 MHz klystron with 800 kW CW output power and 80% efficiency. To reach this goal

With the discovery of the Higgs boson at around 125 GeV, a circular Higgs factory design with high luminosity (L∼1034 cm−2 s−1) is becoming more popular in the accelerator world. The CEPC project in China is one of them. Machine Detector Interface (MDI) is the key research area in electron–positron colliders, especially in CEPC, since the synchrotron radiation (SR) photons can contribute to the heat

The CEPC includes a main ring and an injector. The injector consists of a booster and a linac. In order to meet the requirements of the booster, the baseline design of the linac is a 10 GeV electron and positron linac. Two alternative linac designs have also been introduced in this paper. For the linac baseline design, one-bunch-per-pulse is adopted. A 1.1 GeV damping ring is used to reduce the transverse

The CEPC booster needs to provide electron and positron beams to the collider at different energy with required injection efficiency. At Higgs energy, only the on-axis injection from booster to collider can be fulfilled in CDR. With a consideration of keeping the off-axis injection scheme for safety and reliability, a new booster design based on TME lattice is considered to reduce the emittance by

With the development of the circular collider, it is necessary to make accurate physics experimental measurements of particle properties at higher luminosity Z pole. Micro-pattern gaseous detectors (MPGDs), which contain gaseous electron multiplier (GEM) and micro-mesh gaseous structures (Micromegas), have excellent potential for development as the readout devices of the time projection chamber (TPC)

We discuss the physics opportunities and challenges presented by high energy lepton colliders in the range of center-of-mass energy between few and several tens of TeV. The focus is on the progress attainable on the study of weak and Higgs interactions in connection with new physics scenarios motivated by the shortcomings of the Standard Model.

Dual-readout calorimetry is now a mature and well-known technology which guarantees excellent electromagnetic and hadronic resolution in the same detector. It has recently being proposed in the framework of IDEA (Innovative Detector for Electron–Positron Accelerators) for both Future Circular Collider (FCC-ee) and Circular Electron–Positron Collider (CEPC). After being extensively tested on prototypes

The CMS collaboration reported an intriguing ∼3σ (local) excess at 96 GeV in the light Higgs-boson search in the diphoton decay mode. This mass coincides with a ∼2σ (local) excess in the bb̄ final state at LEP. We briefly review the proposed combined interpretations for the two excesses. In more detail, we review the interpretation of this possible signal as the lightest Higgs boson in the 2 Higgs

While the LHCb detector was specifically designed for measuring heavy-flavor physics, it has also proven itself as a forward general purpose detector with flexible data acquisition, excellent lifetime resolution and charged particle identification. This makes LHCb an ideal laboratory for exploring phenomena related to quantum chromodynamics (QCD), particularly with heavy-flavor content. This review

Quantum chromodynamics (QCD), the theory of the strong interactions, involves quarks interacting with non-Abelian gluon fields. This theory has many features that are difficult to impossible to see in conventional diagrammatic perturbation theory. This includes quark confinement, mass generation and chiral symmetry breaking. This paper is a colloquium level overview of the framework for understanding

We study S4 flavor symmetric inverse seesaw model which has the possibility of simultaneously addressing neutrino phenomenology, dark matter (DM) and baryon asymmetry of the universe (BAU) through leptogenesis. The model is the extension of the standard model by the addition of two (RH) neutrinos and three sterile fermions leading to a keV scale sterile neutrino DM and two pairs of quasi-Dirac states

In this paper, we investigate anisotropic fluid cosmology in a situation where the space–time metric back-reacts in a local, time-dependent way to the presence of inhomogeneities. We derive exact solutions to the Einstein field equations describing Friedmann–Lemaítre–Robertson–Walker (FLRW) large-scale cosmological evolution in the presence of local inhomogeneities and time-dependent backreaction.

In this paper, we have considered the generalized cosmic Chaplygin gas (GCCG) in the background of Brans–Dicke (BD) theory and also assumed that the Universe is filled in GCCG, dark matter and radiation. To investigate the data fitting of model parameters, we have constrained the model using recent observations. Using χ2 minimum test, the best-fit values of the model parameters are determined by OHD+CMB+BAO+SNIa

A modified Hayward metric of magnetically charged black hole space–time based on rational nonlinear electrodynamics with the Lagrangian ℒ=−ℱ/(1+2βℱ) is considered. We introduce the fundamental length, characterizing quantum gravity effects. If the fundamental length vanishes the general relativity coupling to rational nonlinear electrodynamics is recovered. We obtain corrections to the Reissner–Nordström

We present the published data of ALICE at mid-rapidity region (|y|<0.5) to study the pT spectra of light-flavor hadrons in different charged-particle multiplicities (dNchdη) for p+p collisions at s=7 TeV. We parametrize the pT spectra of different hadrons such as pion (π++π−), kaon (K++K−), KS0, K∗0 (K∗0+K∗0̄), ϕ, proton (p+p̄), lambda (Λ+Λ̄), cascade (Ξ−+Ξ̄+) and omega (Ω−+Ω̄+) using Tsallis distribution

In this paper, inflation in the framework of Einstein–Cartan theory is revisited. Einstein–Cartan theory is a natural extension of the General Relativity with nonvanishing torsion. The connection on Riemann–Cartan space–time is only compatible with the cosmological principal for a particular form of torsion. We also show this form to be compatible with gauge invariance principle for non-Abelian and