44328417
Bag formation in a chiral model.
We show that a bag can be automatically formed in a model where the Skyrme Lagrangian is modified to possess the correct QCD scaling behavior.
91179466
Beam commissioning of the PEP-II High Energy Ring
The PEP-II High Energy Ring (HER), a 9 GeV electron storage ring, has been in commissioning since spring 1997. Initial beam commissioning activities focused on systems checkout and commissioning and on determining the behaviour of the machine systems at high beam currents, This phase culminated with the accumulation of 0.75 A of stored beam-sufficient to achieve design luminosity-in January 1998 after 3.5 months of beam time. Collisions with the 3 GeV positron beam of the Low Energy Ring (LER) were achieved in Summer of 1998. At high beam currents, collective instabilities have been seen. Since then, commissioning activities for the HER have shifted in focus towards characterization of the machine and a rigorous program to understand the machine and the beam dynamics is presently underway.
122953784
A hamiltonian structure from gauge transformations of the Zakharov-Shabat system
Abstract We study a hamiltonian structure for nonlinear evolution equations arising from a class of gauge transformations of the Zakharov-Shabat system.
181733866
LASER WELDING OF STEEL PLATES WITH UNMACHINED EDGES
119337087
Investigating the process of star formation in young LMC star clusters
The rich star clusters in the Large Magellanic Cloud (LMC) are ideal for studying the process of star formation. Here we focus on the determination of age spreads amongst the massive stars in two young clusters, NGC1818 and NGC1805. We present colour magnitude diagrams (derived from HST data) for these clusters, and discuss the difficulties in age spread determination.
18232712
Chandra observations of the nearby spiral galaxy NGC6503
We have observed the nearby spiral galaxy NGC6503 using Chandra. Seven discrete sources associated with the galaxy have been found, one of them coincident with its Liner-starburst nucleus. One of the sources corresponds to a ULX with Lx >~ 10e39 ergs/s. Previous ROSAT observations of the galaxy show that this source has varied by at least a factor 3 in the last 6 years. No evidence is found for strong diffuse emission in the nuclear region or the presence of a low luminosity AGN.
41594474
Charm production in neutron-nucleon interactions.
Hadronic production of charmed particles in association with muons from their semileptonic decay has been observed in a high-resolution streamer-chamber experiment performed at Fermilab. A miss-distance analysis of the pictures gives a signal of 17.3 +- 4.7 events. Depending on the production model this corresponds to a range of neutron-nucleon cross sections from 8 to 50 ..mu..b, assuming an A/sup 2/3/ dependence.
117445639
A new collider upgrade proposal: Increasing the pbar-p collider energy
31307451
Double analog state in odd-A nuclei.
Measurements were performed using pion double charge exchange to observe the double isobaric analog state (DIAS) in the odd-[ital A] nuclei [sup 54]V, [sup 59]Co, [sup 115]In, and [sup 197]Au. These results are combined with data for other odd-[ital A] targets and used to investigate the [ital N], [ital Z], and [ital A] dependence of DIAS cross sections.
2512058
Conformal field theory of a rotating dyon.
A conformal field theory representing a four-dimensional classical solution of heterotic string theory is presented. The low-energy limit of this solution has U(1) electric and magnetic charges, and also nontrivial axion and dilaton fields. The low-energy metric contains mass, NUT, and rotation parameters. We demonstrate that this solution corresponds to part of an extremal limit of the Kerr-Taub-NUT dyon solution. This limit displays interesting ``remnant'' behavior in that asymptotically far away from the dyon the angular momentum vanishes, but far down the infinite throat in the neighborhood of the horizon (described by our CFT) there is a nonzero angular velocity. A further natural generalization of the CFT to include an additional parameter is presented, but the full physical interpretation of its role in the resulting low energy solution is unclear.
26932934
Measurements of a Hamiltonian system and their description by a diffusive model.
The dynamics of transverse particle oscillations in the Fermilab Tevatron, artificially made nonlinear, is studied by observing beam profiles over periods up to an hour. A ``diffusive'' model with amplitude-dependent diffusion coefficient gives a quantitatively accurate description of beam evolution. The evolution is influenced strongly by nonlinear resonance.