1,384 research outputs found
Experimental Studies of the NaCs 53Π0 and a3Σ+ States
We report high resolution measurements of 372 NaCs 53Π0(v, J) ro-vibrational level energies in the range 0 ≤ v ≤ 22. The data have been used to construct NaCs 53Π0 potential energy curves using the Rydberg–Klein-Rees and inverted perturbation approximation methods. Bound-free 53Π0(v, J) → 1(a)3Σ+ emission has also been measured, and is used to determine the repulsive wall of the 1(a)3Σ+ state and the 53Π0 → 1(a)3Σ+ relative transition dipole moment function. Hyperfine structure in the 53Π0 state has not been observed in this experiment. This null result is explained using a simple vector coupling model
Production of -pairs at HERA-
The production of -pairs as a possible measure of the polarized gluon
distribution is studied for proton--nucleon collisions at
\sqrt{s} =40\;\mbox{GeV}^2 (HERA-). Possibilities of
reconstructing the helicity state of at least one of the 's are
critically reviewed. The observation of production asymmetries in the single
polarized mode of HERA- is found to be not feasible.Comment: 8 pages, LATeX, 3 figures availabe as .uu-fil
The Richness of the Globular Cluster System of NGC 3923: Clues to Elliptical Galaxy Formation
We present new data on the globular cluster system of the elliptical galaxy
NGC 3923 which show that it has the most globular clusters per unit luminosity
of any non-cluster elliptical yet observed, with . NGC 3923 is
also among the brightest ellipticals outside of a galaxy cluster for which the
number of globular clusters has been determined. Our observation of a large
number of clusters per unit luminosity (high value) for a bright
elliptical in a sparse environment is consistent with the suggestion of
Djorgovski \& Santiago that the number of globular clusters is a power law
function of the luminosity with an exponent greater than one. We relate this
higher specific frequency of globular clusters in more luminous galaxies to
other observations which indicate that the physical conditions within
elliptical galaxies at the time of their formation were dependent on galaxy
mass.Comment: 13 pages + 3 figures, uuencoded postscript, to appear in ApJ Letters,
UC-BERK-9
The influence of image interactivity upon user engagement when using mobile touch screens
Touch screens are a key component of consumer mobile devices such as smartphones and tablets, as well as an increasingly common self-service component of information retrieval on fixed screens and mobile devices in-store. The ubiquity of touch screens in daily life increases consumer accessibility and extended use for shopping, whilst software innovations have increased the functionality of touch screens, for example the extent to which images respond to fingertip control. This study examines how users engage with interactive visual rotation and tactile simulation features while browsing fashion clothing products on touch screen devices and thus contributes to retail touch screen research that previously focused on in-store kiosks and window displays. Findings show that three dimensions of user engagement (endurability, novelty and felt involvement) are positively influenced by both forms of manipulation. In order to examine the extent to which touch screen user engagement varies with individual preferences for an in-store experience, the paper also examines whether user engagement outcomes are mediated by an individual's need for physical touch. Findings indicate that the need for touch does not explain the variance between individuals. We conclude that touch screen technology complements the physical retail environment
The Origin of Primordial Dwarf Stars and Baryonic Dark Matter
I present a scenario for the production of low mass, degenerate dwarfs of
mass via the mechanism of Lenzuni, Chernoff & Salpeter (1992).
Such objects meet the mass limit requirements for halo dark matter from
microlensing surveys while circumventing the chemical evolution constraints on
normal white dwarf stars. I describe methods to observationally constrain this
scenario and suggest that such objects may originate in small clusters formed
from the thermal instability of shocked, heated gas in dark matter haloes, such
as suggested by Fall & Rees (1985) for globular clusters.Comment: TeX, 4 pages plus 2 postscript figures. To appear in Astrophysical
Journal Letter
Rotational Corrections to Axial Currents in Semibosonized SU(3) Nambu--Jona-Lasinio Model
We examine O(1/\Ne) rotational corrections to axial couplings \gt~ and \go~
in the framework of the semibosonized SU(3) Nambu--Jona-Lasinio model. A
novelty is due to the observation that the rotational (cranking) velocity and
the rotation matrix itself do not commute within semiclassical quantization
scheme. If time ordering in the quark loop is maintained new contributions,
which have no analogue in the Skyrme model, appear. They substantially improve
numerical results for the axial couplings which without the present corrections
are badly underestimated.Comment: RUP-TPII-54/93, in LaTeX, 6pages, no figures, in revised version two
references have been update
Gamma ray astronomy and baryonic dark matter
Recently, Dixon et al. have re-analyzed the EGRET data, finding a
statistically significant diffuse -ray emission from the galactic halo.
We show that this emission can naturally be explained within a
previously-proposed model for baryonic dark matter, in which -rays are
produced through the interaction of high-energy cosmic-ray protons with cold
clouds clumped into dark clusters - these dark clusters supposedly
populate the outer galactic halo and can show up in microlensing observations.
Our estimate for the halo -ray flux turns out to be in remarkably good
agreement with the discovery by Dixon et al. We also address future prospects
to test our predictions.Comment: 9 pages, 1 figure included, to appear in ApJ 510, L103 (1999
Popcorn : production and marketing
"K. E. Ziegler, Iowa State University; R. B. Ashman, Purdue University; G. M. White, University of Kentucky; and D. S. Wysong, University of Nebraska ; Reviewers: M. A. Hanna, University of Nebraska Seed Research Committee, Popcorn Institute, IL R. L. Nielsen, Purdue University M. S. Zuber, University of Missouri."--First page.K. E. Ziegler (Iowa State University), R. B. Ashman (Purdue University), G. M. White (University of Kentucky), and D. S. Wysong (University of Nebraska), M. A. Hanna (University of Nebraska Seed Research Committee, Popcorn Institute, IL), R. L. Nielsen (Purdue University), M. S. Zuber (University of Missouri)New 2/85/5
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