Two independent axion searches have been carried out near a well-shielded radioactive $^{65}\mathrm{Zn}$ source (\ensuremath{\sim}15 kCi). One experiment used four NaI(Tl) scintillators to detect coincident photons generated in the decay a\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}. The second shielded 145-${\mathrm{cm}}^{3}$ low-background intrinsic-Ge detector single produced by ``Compton'' interactions with electrons and Primakoff conversion off Ge nuclei Pb shield. We...

Studies of meson spectroscopy have often employed a nonrelativistic Coulomb plus linear confining potential in position space. However, because the quarks mesons move at an appreciable fraction speed light, it is necessary to use relativistic treatment bound-state problem. Such most easily carried out momentum position-space and potentials lead singular kernels Using subtraction procedure we show how remove these singularities exactly thereby solve Schr\"odinger equation space for all...

The phenomenon of collective flow in relativistic heavy ion collisions is studied using the hadronic cascade model ARC. Direct comparison made to data gathered at Bevalac, for Au+Au $p=1-2$ GeV/c. In contrast standard lore about model, well described quantitatively without need explicit mean field terms simulate nuclear equation state. Pion opposite direction nucleon as that anti-nucleons and other produced particles. are predicted AGS energies also, where, light higher baryon densities...

The Land\'e subtraction method is a technique for removing the singularity which arises when one solves Schr\"odinger equation in momentum space Coulomb potential. Using this technique, numerical solutions eigenvalues and eigenfunctions are presented compared to exact results. Approximately 50 can be calculated very accurately various values of angular momentum. Numerous also found accurately. In addition, it shown how implement potentials linear combination potential some other...

▪ Abstract A quantitative model, based on hadronic physics and Monte Carlo cascading, is described applied to heavy ion collisions at BNL-AGS energies (∼ 14 GeV/u). The model was found be in excellent agreement with particle spectra where data previously existed, for Si beams, able successfully predict the were initially absent, Au beams. For + collisions, baryon densities of three or four times normal nuclear matter density (ρ 0 ) are seen theory, whereas up 10 ρ anticipated. possibility...

We reexamine the production of $J/\ensuremath{\psi}$ and other charmonium states for a variety target-projectile choices at CERN Super Proton Synchrotron, in particular interesting comparison between S+U $200 \mathrm{GeV}/c$ Pb+Pb $158 as observed experiments NA38 NA50, respectively. For this study we use newly constructed cascade code LUCIFER II, which yields acceptable descriptions both hard soft processes, specifically Drell-Yan meson production. This divides ion-ion collision into an...

A method is presented for the solution in momentum space of bound-state problem with a linear potential r space. The unbounded at large leading to singularity small q. integrable, when regulated by exponentially screening r-space potential, and removed subtraction technique. limit zero taken analytically, numerical subtracted integral equation gives eigenvalues wave functions good agreement position calculations.

The spinless Salpeter equation with the Coulomb potential is solved exactly in momentum space and shown to agree very well a coordinate-space calculation. agreement so good that it clearly establishes procedure discussed can be used reliably calculate fine-structure effects any bound-state system without relying on approximations. works no matter how large coupling constant. An equation, called retardation, introduced this also able exactly.

A simulation is performed of the recently reported data from PHOBOS at energies $\sqrt{s}=56,130A$ GeV using relativistic heavy ion cascade LUCIFER which had previously given a good description NA49 inclusive spectra $\sqrt{s}=17.2A$ GeV. The results compare well with these early measurements RHIC.

Several recent experiments have reported evidence for a narrow feature in the ${K}^{+}$-neutron system, an apparent resonant state $\ensuremath{\sim}100\mathrm{MeV}$ above threshold and with width $<~25\mathrm{MeV}.$ This has been labeled as ${\ensuremath{\Theta}}^{+}$ (previously ${Z}^{*}),$ because of implied inclusion strange antiquark is referred to pentaquark, that is, five quarks within single bag. We present alternative explanation such structure, higher angular momentum resonance...

Recent experiments at the LHCb detector have once again raised possibility that quark bags may exist containing more than three quarks. Specifically collaboration points to evidence for hadronic resonances decaying into J/$\psi$ and proton: $P_c(4450)^+$ $P_C(4380)^+$. Here we put forth a case reasonable description of these states is possible as molecular $p$ J/$\psi$. Our model seems accommodate observed their measured widths, both lower lying, broader, negative parity state higher narrow...

Deuteron coalescence, during a relativistic nucleus-nucleus collision, is carried out in model incorporating minimal quantal treatment of the formation cluster from its individual nucleons by evaluating overlap initial cascading nucleon wave packets with final deuteron function. The packet sizes are estimated dynamically using coalescing pair's past light-cone history. A parameter free determination absolute yields results, and globally consistent picture Si+Au measurements achieved. In...

A two phase cascade is presented for ultrahigh energy ion-ion collisions from $\sqrt{s}=17--200\mathrm{GeV}.$ First a high-energy performed, in which original baryons and any freed hard partons collide. This stage ignores loss soft processes. In this first version no processes, aside Drell-Yan production, are included. The space-time history of the used to reconstruct loss. Soft meson production treated as coherent over groups interacting nucleons. Two body data, though, guide...

A Comment on the Letter by D. Beavis, et al., Phys. Rev. Lett. 75, 3633 (1995). The authors of offer a Reply.Received 8 August 1996DOI:https://doi.org/10.1103/PhysRevLett.78.3418©1997 American Physical Society

In a recent experiment E906 at the BNL-AGS, in which search for light $S=\ensuremath{-}2$ hypernuclei was carried out, strong evidence nuclide ${}_{\ensuremath{\Lambda}\ensuremath{\Lambda}}^{ 4}\mathrm{H}$ found. One of most striking components this data appearance narrow low-momentum ${\ensuremath{\pi}}^{\ensuremath{-}}$ line ${k}_{\ensuremath{\pi}}=104--105\mathrm{MeV}/c.$ This ascribed to decay into resonant state ${}_{\ensuremath{\Lambda}}^{4}\mathrm{He}.$ The existence such is shown be...

Solutions of two-body, bound-state equations have recently been developed for quark-antiquark pairs. These solutions use a confining potential in momentum space as input into threedimensional reductions the Bethe-Salpeter equation using special subtraction procedures. Regge trajectories are calculated Schr\"odinger which display well-known unphysical behavior where lower mass overlap higher ones and also nonlinearity. Both these features contradict experiment. obtained from Thompson...

A new two-body relativistic equation is presented. The major advantage of the proposed over existing equations in literature that this automatically adjusts itself for different mass systems. Besides unitarity and covariance, gives a physically meaningful prescription how particles go off-mass-shell intermediate states. It allows to proportionally their masses so when one becomes infinite, it one-body lighter particle equal systems, reduces Todorov equation. Because states, will be useful...

Au+Au, $s^{1/2} = 200$ A GeV measurements at RHIC, obtained with the PHENIX, STAR, PHOBOS and BRAHMS detectors, have all indicated a suppression of neutral pion production, relative to an appropriately normalized NN level. For central collisions vanishing pseudo-rapidity these experiments exhibit in charged meson especially medium large transverse momenta. In PHENIX experiment similar behavior has been reported for $π^0$ spectra. recent work on simpler D+Au interaction, be considered perhaps...