121446915
Generating function zeros for hadron multiparticle distributions
A theorem is proved that delineates criteria for the radii of the annulus of the zeros in the complex plane of the generating function for factorial moments as it applies to high-energy charged-hadron multiproduction. It is shown how this theorem and the general features of the negative binomial distribution provide an explanation of the distribution of generating-function zeros along an open circular ring of approximately unit radius found in simulations and collider data. {copyright} {ital 1997} {ital The American Physical Society}
120828806
HAMILTONIAN BRST QUANTIZATION OF THE INTERACTING ANTISYMMETRIC TENSOR FIELD
Abstract We study the hamiltonian BRST quantization of the non-abelian antisymmetric tensor field. We find the constrained system which arises from the standard action by Dirac's procedure, and eliminate the second-class constraints by introducing Dirac brackets. Having isolated the underlying first-class constrained system, we quantize it using the hamiltonian BRST techniques of Batalin and Fradkin. We study the Lorentz covariant gauge fixing of this system, and discuss the relationship between our results and other recent studies of the interacting antisymmetric tensor field.
120344295
Superspace supergravity from the superstring
Abstract We study a classical superstring propagating in a “curved” (10,16)-dimensional superspace. In this formulation of the string, a local fermionic symmetry is needed to eliminate ghosts from the particle spectrum. By studying the constraint algebra, we show that any background field configuration consistent with this symmetry is equivalent to one which satisfies the full set of supergravity equations.
120178876
Constraint algebra of open string field theory in midpoint coordinates
Abstract We study the canonical structure of string field theory in midpoint coordinates. We find the constraint algebra, which consists of second class constraints, together with dependent first class constraints. Exploiting properties of the relevant operators, we show that the constraint algebra is the same in the interacting theory as in the free theory, at least on Fock-space states. We discuss the gauge transformations generated by the first class constraints, and show that they can be used to gauge away unphysical fields.
119471275
A Chern-Simons-like action for closed-string field theory
A Chern-Simons-like action is proposed for closed-string field theory. The action involves auxiliary fields of arbitrary ghost number and is defined in terms of the closed-string operations integral , Q and, analogous to those introduced by Witten (1986) in the construction of open-string field theory. The action is an extension of one proposed for free closed strings and bears a formal relationship to 2+1 gravity analogous to that between open-string field theory and (2+1)-dimensional Yang-Mills theory.
33049133
Vacuum structure, zero modes, and the effective potential in light-cone quantization.
A Hamiltonian formalism for the calculation of the usual effective potential is presented in the context of scalar field theory. When applied in the context of light-cone quantization, we find contributions at [ital k][sup +]=0 which are missed by standard light-cone infrared regularizations. We present a (time-dependent) regularization of the Hamiltonian which correctly incorporates these contributions at the one-loop level. We briefly discuss the implications of these findings for the more general program of diagonalizing the light-cone Hamiltonian.
16833520
The H I Companions of H II Galaxies and Low Surface Brightness Dwarf Galaxies
I study the VLA H I survey of H II galaxies by Taylor et al. and the VLA H I survey of low surface brightness (LSB) dwarf galaxies by Taylor et al. to investigate the role of galaxy interactions in triggering the bursts of massive star formation seen in H II galaxies. Comparing the two surveys, I find that H II galaxies have companions more than twice as often as LSB dwarfs (p = 0.57 for H II galaxies, compared to p = 0.24 for LSB dwarfs). I examine the completeness of the companion samples detected by the two surveys. For the companions to H II galaxies, the sample is likely complete in the distribution of velocity separations from their parent galaxies but is probably missing some companions at large projected linear separations because of the finite size of the VLA primary beam. For the companions of LSB dwarfs, the small number of detections means their distributions in velocity and linear separation are poorly determined, but the LSB dwarfs were observed with the same observational setup as the H II galaxies, so they will have the same levels of completeness. Because the two samples were observed in exactly the same fashion, there will be no relative bias in the number of companions introduced in this way. In addition, the redshift distributions of the two samples are very similar, so there will not be a distance-related relative bias. Thus, I conclude that the difference in the number of H I rich companions is genuine, and signifies a difference in the local, small-scale environments between the two types of galaxy. I search through published galaxy catalogs to determine number of neighbors each galaxy has outside the area of the VLA observations. At these large separations, the number of neighbors is the same, within the errors, for the two types of galaxy. The high rate of companion occurrence at low separations for H II galaxies relative to LSB dwarfs supports the hypothesis that the bursts of star formation are triggered by galaxy interactions.
14127729
THE ORIGIN OF THE DUST ARCH IN THE HALO OF NGC 4631: AN EXPANDING SUPERBUBBLE?
We study the nature and the origin of the dust arch in the halo of the edge-on galaxy NGC 4631 detected by Neininger & Dumke. We present CO observations made using the new on-the-fly mapping mode with the Five College Radio Astronomy Observatory 14 m telescope and find no evidence for CO emission associated with the dust arch. Our examination of previously published H I data shows that, if previous assumptions about the dust temperature and gas/dust ratio are correct, then there must be molecular gas associated with the arch, below our detection threshold. If this is true, then the molecular mass associated with the dust arch is between 1.5 × 108 M⊙ and 9.7 × 108 M⊙, and likely toward the low end of the range. A consequence of this is that the maximum allowed value for the CO-to-H2 conversion factor is 6.5 times the Galactic value, but most likely closer to the Galactic value. The kinematics of the H I apparently associated with the dust arch reveals that the gas here is not part of an expanding shell or outflow but is instead two separate features (a tidal arm and a plume of H I sticking out into the halo) that are seen projected together and appear as a shell. Thus there is no connection between the dust "arch" and the hot X-ray–emitting gas that appears to surround the galaxy.