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T. Csorgo

Publications and source records attributed to T. Csorgo.

At least 19 recordsLinked to original sources

Observation of Odderon Effects at LHC energies -- A Real Extended Bialas-Bzdak Model Study

The unitarily extended Bialas-Bzdak model of elastic proton-proton scattering is applied, without modifications, to describe the differential cross-section of elastic proton-antiproton collisions in the TeV energy range, and to extrapolate these differential cross-sections to LHC energies. In this model-dependent study we find that the differential cross-sections of elastic proton-proton collision data at 2.76 and 7 TeV energies differ significantly from the differential cross-section of elastic proton-antiproton collisions extrapolated to these energies. The elastic proton-proton differential cross-sections, extrapolated to 1.96 TeV energy with the help of this extended Bialas-Bzdak model do not differ significantly from that of elastic proton-antiproton collisions, within the theoretical errors of the extrapolation. Taken together these results provide a model-dependent, but statistically significant evidence for a crossing-odd component of the elastic scattering amplitude at the at least 7.08 sigma level. From the reconstructed Odderon and Pomeron amplitudes, we determine the $\sqrt{s}$ dependence of the corresponding total and differential cross-sections.

hep-ph

Evidence of Odderon-exchange from scaling properties of elastic scattering at TeV energies

We study the scaling properties of the differential cross section of elastic proton-proton ($pp$) and proton-antiproton ($p\bar p$) collisions at high energies. We introduce a new scaling function, that scales -- within the experimental errors -- all the ISR data on elastic $pp$ scattering from $\sqrt{s} = 23.5$ to $62.5$ GeV to the same universal curve. We explore the scaling properties of the differential cross-sections of the elastic $pp$ and $p\bar p$ collisions in a limited TeV energy range. Rescaling the TOTEM $pp$ data from $\sqrt{s} = 7$ TeV to $2.76$ and $1.96$ TeV, and comparing it to D0 $p\bar p$ data at $1.96$ TeV, our results provide an evidence for a $t$-channel Odderon exchange at TeV energies, with a significance of at least 6.26$σ$. We complete this work with a model-dependent evaluation of the domain of validity of the new scaling and its violations. We find that the $H(x)$ scaling is valid, model dependently, within $200$ GeV $ \leq \sqrt{s} \leq$ $ 8$ TeV, with a $-t$ range gradually narrowing with decreasing colliding energies.

hep-ph

A simple family of solutions of relativistic viscous hydrodynamics for fireballs with Hubble flow and ellipsoidal symmetry

New, analytic solutions of relativistic viscous hydrodynamics are presented, describing expanding fireballs with Hubble-like velocity profile and ellipsoidal symmetry, similar to fireballs created in heavy ion collisions. We find that with these specifications, one obtains solutions where the shear viscosity essentially does not influence the time evolution of the system, thus these solutions are particularly adept tools to study the effect of bulk viscosity alone, which always results in a slower decrease of energy density as well as temperature compared to the case of perfect fluid. We investigate different scenarios for the bulk viscosity and find qualitatively different effects on the time evolution which suggests that there is a possibility to infer the value of bulk viscosity from energy density and temperature measurements in high-energy heavy-ion collisions.

nucl-th

New, multipole solutions of relativistic, viscous hydrodynamics

We present a new class of exact fireball solutions of relativistic dissipative hydrodynamics. We describe new exact solutions both for the relativistic Navier-Stokes and for the Israel-Stewart theory, for arbitrary shear and bulk viscosities, as well as for other dissipative coefficients. The common property of these solutions is the presence of the relativistic Hubble flow. Our results generalize the recently found first solution in these classes, for an arbitrary temperature dependent speed of sound, shear and bulk viscosity, heat conduction and fluctuating initial temperature profiles. These solutions are causal and not only stable but also asymptotically perfect. A strong and narrow peak in the kinematic bulk viscosity is shown to imitate the effects of a first order phase transition. The new class of asymptotically perfect solutions is thus found to be very rich, but at the same time mostly academic as the solutions are limited by the spherical symmetry of the Hubble flow field.

nucl-th

Lifetime estimations and a non-monotonic initial energy density in heavy ion collisions at RHIC and LHC

We highlight some connections between the final state hadronic observables and the initial conditions using a recently found new exact family of solutions of relativistic hydrodynamics. These relations provide explicit examples of the scaling behaviour in relativistic hydrodynamics and may provide an advanced estimate of the lifetime and the initial energy density in $\sqrt{s_{NN}} = 62.4$, $130$, and $200$ GeV Au+Au collisions at RHIC and $\sqrt{s_{NN}} = 5.0$ TeV Pb+Pb and $5.44$ TeV Xe+Xe as well as $\sqrt{s} = 7$, $8$ and $13$ TeV p+p collisions at LHC energies. A surprising result is that these advanced estimates yield a non-monotonic increase of the initial energy density with increasing collision energy at the RHIC energy range.

nucl-th

Proton Holography -- Discovering Odderon from Scaling Properties of Elastic Scattering

We investigate the scaling properties of elastic scattering data at ISR and LHC energies and find that the significance of an Odderon observation is larger than the discovery threshold of 5$σ$. As an unexpected by-product of these investigations, for certain experimentally relevant cases, we also conjecture the possibility of proton holography with the help of elastic proton-proton scattering.

hep-ph

Odderon and proton substructure from a model-independent Levy imaging of elastic $pp$ and $p\bar p$ collisions

We describe a new and model-independent Lévy imaging method of quality fits to the published datasets and reconstruct the amplitude of high-energy $pp$ and $p\bar p$ elastic scattering processes. This method allows us to determine the excitation function of the shadow profile $P(b)$, the elastic slope $B(t)$ and the nuclear phase $ϕ(t)$ functions of $pp$ and $p\bar p$ collisions directly from the data. Surprisingly, notable qualitative differences in $B(t)$ for $pp$ and for $p\bar p$ collisions point towards an Odderon effect. As a by-product, we clearly identify the proton substructure with two different sizes at the ISR and LHC energies, that has striking similarity to a dressed quark (at the ISR) and a dressed diquark (at the LHC). We present model-independent results for the corresponding sizes and cross-sections for such a substructure for the existing data at different energies.

hep-ph

Model-independent femtoscopic Levy imaging for elastic proton-proton scattering

A model independent Levy expansion method is introduced to describe nearly Levy shaped squared moduli of Fourier transforms. We apply this method to precisely characterize the most recent elastic scattering data of proton-proton collisions at $\sqrt{s} = 13$ TeV. The results reveal a substructure of protons, which is found to be significantly larger and darker in high energy proton-proton collisions at the TeV scale, as compared to a rather faint and apparently overlooked sub-structure, that we also identify in elastic proton-proton scattering at the ISR energy range of $\sqrt{s} = 23 - 62$ GeV.

hep-ph

A new and finite family of solutions of hydrodynamics. Part I: Fits to pseudorapidity distributions

We highlight some of the interesting properties of a new and finite, exact family of solutions of 1 + 1 dimensional perfect fluid relativistic hydrodynamics. After reviewing the main properties of this family of solutions, we present the formulas that connect it to the measured rapidity and pseudo-rapidity densities and illustrate the results with fits to p+p collisions at 8 TeV and Pb+Pb collisions at $\sqrt{s_{NN}} = 5.02 $ TeV.

nucl-th

Pseudorapidity and initial energy densities in p+p and heavy ion collisions at RHIC and LHC

A known exact and accelerating solution of relativistic hydrodynamics for perfect fluids is utilized to describe pseudorapidity densities of $\sqrt{s_{NN}} = 5.02$ TeV Pb$+$Pb and $\sqrt{s}=13$ TeV $p$$+$$p$ collisions at LHC. We evaluate a conjectured initial energy densities $ε_{\rm corr}$ in these collisions, and compare them to Bjorken's initial energy density estimates, and to results for Pb$+$Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV and $p$$+$$p$ collisions at $\sqrt{s} = 7$ and 8 TeV.

nucl-th

New exact solutions of relativistic hydrodynamics for longitudinally expanding fireballs

We present new, exact, finite solutions of relativistic hydrodynamics for longitudinally expanding fireballs for arbitrary constant value of the speed of sound. These new solutions generalize earlier, longitudinally finite, exact solutions, from an unrealistic to a reasonable equation of state, characterized by a temperature independent (average) value of the speed of sound. Observables like the rapidity density and the pseudorapidity density are evaluated analytically, resulting in simple and easy to fit formulae that can be matched to the high energy proton-proton and heavy ion collision data at RHIC and LHC. In the longitudinally boost-invariant limit, these new solutions approach the Hwa-Bjorken solution and the corresponding rapidity distributions approach a rapidity plateaux.

nucl-th

Observables and initial conditions for rotating and expanding fireballs with spheroidal symmetry

Utilizing a recently found class of exact, analytic rotating solutions of non-relativistic fireball hydrodynamics, we calculate analytically the single-particle spectra, the elliptic flows and two-particle Bose-Einstein correlation functions for rotating and expanding fireballs with spheroidal symmetry. We demonstrate, that rotation generates final state momentum anisotropies even for a spatially symmetric, spherical initial geometry of the fireball. The mass dependence of the effective temperatures, as well as the HBT radius parameters and the elliptic flow are shown to be sensitive not only to radial flow effects but also to the magnitude of the initial angular momentum.

nucl-th

Rotation in an exact hydro model

We study an exact and extended solution of the fluid dynamical model of heavy ion reactions, and estimate the rate of slowing down of the rotation due to the longitudinal and transverse expansion of the system. The initial state parameters of the model are set on the basis of a realistic 3+1D fluid dynamical calculation at TeV energies, where the rotation is enhanced by the build up of the Kelvin Helmholtz Instability in the flow.

hep-ph

Elastic proton-proton scattering from ISR to LHC energies, focusing on the dip region

The differential cross-section of elastic proton-proton collisions is studied at ISR and LHC energies, utilizing a quark-diquark model, that generalizes earlier models of Bialas and Bzdak, and, in addition, a model of Glauber and Velasco. These studies suggest that the increase of the total pp cross-section is mainly due to an increase of the separation of the quark and the diquark with increasing energies. Within the investigated class of models, two simple and model-independent phenomenological relations were found, that connect the total pp scattering cross-section to the effective quark, diquark size and their average separation, on one hand, and to the position of the dip of the differential cross-section, on the other hand. The latter t(dip) sigma(tot) ~ const relation can be used to predict t(dip), the position of the dip of elastic pp scattering for future colliding energies, and for other reactions, where sigma(tot) is either known or can be reliably estimated.

hep-ph

Higgs Boson -- on Your Own

One of the highlights of 2012 in physics is related to two papers, published by the ATLAS and the CMS Collaborations, that announced the discovery of at least one new particle in pp collisions at CERN LHC. At least one of the properties of this new particle is found to be similar to that of the Higgs boson, the last and most difficult to find building block from the Standard Model of particle physics. Physics teachers are frequently approached by their media-educated students, who inquire about the properties of the Higgs boson, but physics teachers are rarely trained to teach this elusive aspect of particle physics in elementary, middle or junior high schools. In this paper I describe a card-game, that can be considered as a hands-on and easily accessible tool that allows interested teachers, students and also motivated lay-persons to play with the properties of the newly found Higgs-like particle. This new particle was detected through its decays to directly observable, final state particles. Many of these final state particles are represented in a deck of cards, that represent elementary particles, originally invented to popularize the physics of quark matter in the so-called Quark Matter Card Games. The Higgs decay properties can be utilized, playfully, in a Higgs boson search card game. The rules of this game illustrate also the need for some luck, to complement knowledge and memory, useful skills that this game also helps to develop. The paper is organized as a handout or booklet, that directly describes how to play the Higgs boson on Your Own card game.

physics.pop-ph

First Results from the TOTEM Experiment

The first physics results from the TOTEM experiment are here reported, concerning the measurements of the total, differential elastic, elastic and inelastic pp cross-section at the LHC energy of $\sqrt{s}$ = 7 TeV, obtained using the luminosity measurement from CMS. A preliminary measurement of the forward charged particle $η$ distribution is also shown.

hep-ex

Significant in-medium eta' mass reduction in sqrt(s(NN))=200 GeV Au+Au collisions at the BNL Relativistic Heavy Ion Collider

In high energy heavy ion collisions a hot and dense medium is formed, where the U_A(1) or chiral symmetry may temporarily be restored. As a consequence, the mass of the eta'(958) mesons may be reduced to its quark model value, and the abundance of eta' mesons at low p_T may be enhanced by more than a factor of 10. The intercept parameter lambda_* of the charged pion Bose--Einstein correlations provides a sensitive observable of the possibly enhanced eta' abundance. We have analyzed lambda_*(m_T) data from sqrt(s(NN))=200 GeV central Au+Au reactions measured at the BNL Relativistic Heavy Ion Collider (RHIC), using extensive Monte Carlo simulations based on six popular models for hadronic multiplicities. Based on the combined STAR and PHENIX data set, and on various systematic investigations of resonance multiplicities and model parameters, we conclude that in sqrt(s(NN))=200 GeV central Au+Au reactions the mass of the eta' meson is reduced by Delta m > 200 MeV, at the 99.9% confidence level in the considered model class. Such a significant eta' mass modification may indicate the restoration of the U_A(1) symmetry in a hot and dense hadronic matter and the return of the ninth "prodigal" Goldstone boson. A similar analysis of NA44 S+Pb data at top CERN Super Proton Synchrotron (SPS) energies showed no significant in-medium eta' mass modification.

nucl-ex

Oscillating HBT radii and the time evolution of the source - sqrt(s_NN) = 200 GeV Au+Au data analyzed with azimuthally sensitive Buda-Lund hydro model

Identified particle spectra of pions, kaons and (anti)protons, and elliptic flow and azimuthal dependence of Bose-Einstein or HBT correlations of identified pions in sqrt(s_NN) = 200 GeV Au+Au collisions is analyzed simultaneously using an ellipsoidally symmetric generalization of the Buda-Lund hydrodynamical model. The transverse flow is found to be faster in the reaction plane than out of plane, which results in a reaction zone that gets slightly more elongated in-plane than out of plane.

nucl-th