45414206
Measurement of the penetration depth and coherence length in U(1) and SU(2) dual Abrikosov vortices
Abstract We calculate the electric field and the curl of the magnetic monopole current for U(1) and for SU(2) in the maximal Abelian gauge in the mid-plane between a quark antiquark pair. The results can be understood as a dual Abrikosov vortex in the Ginzburg-Landau theory.
121208723
Profiles of the confining tube
Abstract Progress in studying colour fields generated by static sources in quenched and unquenched QCD is reported.
13534871
Vacuum structure of pure gauge theories on the lattice
Results from simulations on two aspects of quark confinement in the pure gauge sector are presented. First is the calculation of the profile of the flux tube connecting a static q[bar q] pair in SU(2). By use of the Michael sum rules as a constraint, evidence is set forth that the energy density at the center of the flux tube goes to a constant as a function of quark- separation. Slow variation of the width and energy density is not ruled out. Secondly in the confined phase of lattice U(l), the curl of the magnetic monopole current is calculated, and it is shown that the dual London equation is satisfied and that the electric fluxoid is quantized.
121664310
Energy and action of the colour fields around static quarks
Abstract Results on the profiles of the confining tube in the energy and action densities are discussed. Lattice sum rules are tested in detail.
118798864
Monopoles and Confinement in Lattice-Gauge Theory.
A C K N O W LED G EM ENTS I am indebted to my advisor, R ichard H aym aker, for his guidance, pa­ tience and encouragem ent during this p ro ject. I am happy to thank him for m any hours of fruitful discussions, for m uch help w ith program m ing, and for taking a lot of trouble to help me gain an appreciation of particle physics in general. I am grateful for his support in encouraging me to a tten d various conferences and sum m er schools, and in giving me the opportun ity to present talks. I am also happy to thank our collaborator, D ana Browne for encour­ agem ent and advice, for being very generous w ith his time, for invaluable help w ith this p ro ject, and also for helping me w ith program m ing, w riting papers, and Tq X . I am also glad to acknowledge useful discussions and help from Chen-H an Lee. I would also like to thank my friends C hristopher C hapm an, Shyamoli C haudhuri, C h itra Guruswamy, Ja i Won Kim, Evan M auceli, Ying Cai Peng, Vijay Poduri, Hossein Sadeghpour, Z ahra Sadeghpour, Jyo tsna V ijapurkar. Bing Yu, and Lijun Zhang, for the ir help and support. M ost of all, I am indebted to my family, w ithout whose support and encouragem ent this work would not have been possible. This work was done on the Physics SUN cluster (LEQSF(90-92)-ENH-12) and on the IBM 3090.
1626474
Maximally realistic causal quantum mechanics
Abstract We present a causal Hamiltonian quantum mechanics in 2 n -dimensional phase space which is more realistic than de Broglie–Bohm mechanics. The positive definite phase space density reproduces as marginals the correct quantum probability densities of n +1 different complete commuting sets of observables e.g. positions, momenta and n −1 other sets.
122369339
Electron identification and the detection of synchrotron radiation with a preshower detector
Abstract Results are presented from testbeam measurements made with a scintillating fiber preshower detector. The detector was designed to study the early development of electromagnetic showers and the conversion of synchrotron radiation photons. It was constructed with a 0.5 mm transverse granularity, and eight 0.25 radiation length ( X 0 ) longitudinal samplings. Data were taken with 50 GeV pions and electrons with energies between 10 and 200 GeV. Measurements, for electrons, of both the energy deposited and the shower width as a function of depth are presented in this paper. In addition, data were taken with a 1.8 m long magnet with a 2.5 T field placed directly upstream of the detector and the synchrotron radiation photons, generated by the electrons traversing it, were observed in our detector. Electron identification efficiencies and pion rejection factors based on the synchrotron radiation signal and the energy deposited in the last sampling layer (1.75 X 0 ) are presented.
121061804
Generalized beable quantum field theory
Abstract Generalising the Broglie-Bohm quantum mechanics without wave-function collapse, Bell formulated the “beable quantum field theory”. The local beables n ( t ) exist independent of observation and, together with the state vector | t 〉, specify completely the state of the world at time t . We calculate the most general transition probabilities between different beable configurations, such that the resulting probability P n ( t ) for configuration n coincides with that in ordinary quantum field theory. Bell's formula is a special case.
121796381
Higher order JWKB expressions for the energy levels and the wavefunction at the origin
We derive an exact quantization condition for the energy levels of a particle in a radial potential assumed finite at the origin. This is used to derive corrections to the semiclassical JWKB quantization condition. We further relate the normalization integral of the wavefunction to the energy derivative of wavefunction at origin and use this expression to derive the corrections to the semiclassical JWKB expressions for the wavefunction at origin. An application to upsilon leptonic decay width is also given.
118383356
System size dependence of hadron $p_T$ spectra in p+p and Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
We make a systematic study of transverse momentum ($p_T$) spectra of hadrons produced in $p+p$ and in different centralities of Au+Au collisions at $\sqrt{s}=200$\,GeV using phenomenological fit functions. The Tsallis distribution gives a very good description of hadron spectra in $p+p$ collisions with just two parameters but does not produce the same in Au+Au collisions at intermediate $p_{T}$. To explain the hadron spectra in heavy ion collisions in a wider $p_{T}$ range we propose a modified Tsallis function by introducing an additional parameter which accounts for collective flow. The new analytical function gives a very good description of both mesons and baryons spectra at all centralities of Au+Au collisions in terms of parameters having a potential physics interpretation. With this modified Tsallis function we study the spectra of pions, kaons, protons, $\Lambda(1115)$ and $\Xi^{-}$ as a function of system size at $\sqrt{s_{NN}}$ = 200 GeV. The parameter representing transverse flow increases with system size and is found to be more far baryons than that for mesons in central Au+Au collisions. The freeze-out temperature for baryons increases with centrality in Au+Au collisions more rapidly than for mesons.