118505391
Net Charge Fluctuations as a signal of QGP from Polyakov-Nambu-Jona-Lasinio model
We report the first model study of the net charge fluctuations in terms of D-measure within the framework of the Polyakov-Nambu-Jona-Lasinio model. Net charge fluctuation is estimated from the charge susceptibility evaluated using PNJL model. A parameterization of the freeze-out curve has been used to obtain D as a function of sqrt(s). We have discussed our results vis-a-vis recent experimental findings from ALICE collaboration.
122350530
Models for Strong Interaction Physics
Abstract We review the developments in various models describing strong interaction physics. The models provide an intuitive way of understanding the complex phenomenon associated with strong interactions. Models also help us to delve into regions of couplings and other thermodynamic conditions of interest that are still out of reach of the first principle method - quantum chromodynamics. At the same to ascertain the merits of the models they should be contrasted to the results obtained from quantum chromodynamics at least in its region of validity, and to the available experimental data. Here we shall discuss about our progress in that direction.
118413103
Entropy scaling and thermalization in hadron-hadron collisions at LHC
The recent LHC data have once more brought the issue of the formation of thermalized state of matter in hadron-hadron collisions into the forefront. In this letter, we have shown that the scaling of the information entropy of the chaotically produced particles is valid up to recently available data from p+p collisions at $\sqrt{s}$ = 2.36 TeV obtained by ALICE experiment. We predict that at the highest energies projected for LHC, almost all the particles will be produced chaotically, indicating that a collective behavior should be observed in hadronic collisions, as indicated by one of present authors quite some time ago.
17726542
Formation and collapse of false vacuum bubbles in relativistic heavy-ion collisions
Abstract It is possible that under certain situations, in a relativistic heavy-ion collision, partons may expand out forming a shell like structure. We analyze the process of hadronization in such a picture for the case when the quark–hadron transition is of first order, and argue that the inside region of such a shell must correspond to a supercooled (to T=0 ) deconfined vacuum. Hadrons from that region escape out, leaving a bubble of pure deconfined vacuum with large vacuum energy. This bubble undergoes relativistic collapse, with highly Lorentz contracted bubble walls, and may concentrate the entire energy into extremely small regions. Eventually different portions of bubble wall collide, with the energy being released in the form of particle production. Thermalization of this system can lead to very high temperatures. With a reasonably conservative set of parameters, at LHC, the temperature of the hot spot can reach as high as 3 GeV, and well above it with more optimistic parameters. Such a hot spot can leave signals like large P T partons, dileptons, and enhanced production of heavy quarks. We also briefly discuss a speculative possibility where the electroweak symmetry may get restored in the highly dense region resulting from the decay of the bubble wall via the phenomenon of non-thermal symmetry restoration (which is usually employed in models of pre-heating after inflation). If that could happen then the possibility may arise of observing sphaleron induced baryon number violation in relativistic heavy-ion collisions.
119158093
The consequences of SU (3) colorsingletness, Polyakov Loop and Z (3) symmetry on a quark–gluon gas
Based on quantum statistical mechanics we show that the SU(3) color singlet ensemble of a quark-gluon gas exhibits a Z(3) symmetry through the normaized character in fundamental representation and also becomes equivalent, within a stationary point approximation, to the ensemble given by Polyakov Loop. Also Polyakov Loop gauge potential is obtained by considering spatial gluons along with the invariant Haar measure at each space point. The probability of the normalized character in SU(3) vis-a-vis Polyakov Loop is found to be maximum at a particular value exhibiting a strong color correlation. This clearly indicates a transition from a color correlated to uncorrelated phase or vise-versa. When quarks are included to the gauge fields, a metastable state appears in the temperature range 145 T(MeV) 170 due to the explicit Z(3) symmetry breaking in the quark-gluon system. Beyond T 170 MeV the metastable state disappears and stable domains appear. At low temperature a dynamical recombination of ionized Z(3) color charges to a color singlet Z(3) confined phase is evident along with a confining background that originates due to circulation of two virtual spatial gluons but with conjugate Z(3) phases in a closed loop. We also discuss other possible consequences of the center domains in the color deconfined phase at high temperature.
119152850
Wakes in a collisional quark-gluon plasma
Wakes created by a parton moving through a static and infinitely extended quark?gluon plasma are considered. In contrast to former investigations, collisions within the quark?gluon plasma are taken into account using a transport theoretical approach (Boltzmann equation) with a Bhatnagar?Gross?Krook collision term. Within this model, it is shown that the wake structure changes significantly compared to the collisionless case.
123723655
The NOvA experiment
The NOvA Project will construct a 15 kt Far Detector 835 km from Fermilab at Ash River Minnesota, a 220 ton Near Detector on the Fermilab site and upgrade the existing NuMI beamline from 400 kW to 700 kW. The detector technology is liquid scintillator captured in reflective rigid PVC cells. The light is captured using WLS fibre and routed to avalanche photo diodes. NO?A is designed to observe the appearance of electron neutrinos, determine the value of sin{sup 2}(2{theta}{sub 13}) and begin the study of CP violation in the neutrino sector. NO?A is the only currently approved experiment with the ability to determine the neutrino mass ordering. The NOvA physics program and projected sensitivities are described in this report.
125360362
A program to measure the direct CP violating decay K(L) --> pi0 nu anti-nu and other rare decays at Fermilab using the main injector
116924174
Search for new strange resonances in inclusive charged kaon spectra from p̄p annihilation at rest
Charged spectra from pp annihilations at rest have been measured using the PS183 spectrometer at LEAR. From these data, charged kaon spectra are produced using time‐of‐flight separation. The spectra show structures corresponding to annihilation into the K±K−+ and K*±K−+ channels. A search for structures indicating other resonances is discussed.
126084521
Measurements of the widths of charmonium states at the Fermilab anti-p accumulator ring
116328057
The KTeV Pure CsI Calorimeter
KTeV is currently building a state-of-the-art pure CsI electromagnetic calorimeter with a sophisticated digital readout. The CsI array is expected to have better than 1% resolution over a dynamic range of 2--64 GeV. The design of the CsI array is driven by the difficult physics goal of attempting to measure the CP violation parameter Re({epsilon}{prime}/{epsilon}) to 1 part in 10000 in a high-rate neutral beam environment. The physics requirements and their impact on the final design will be discussed.