31,503 research outputs found
Associated Charmonium Production in p-pbar Annihilation
In this paper we summarize our recent results for low energy associated
charmonium production cross sections, using 1) crossing symmetry, and 2) an
explicit hadronic model. These predictions are of relevance to the planned
charmonium and charmonium hybrid production experiment PANDA at GSI.Comment: 5 pages, 5 figures. Contribution to the Second Meeting of the APS
Topical Group on Hadron Physics GHP2006. (Nashville, TN, 22-24 Oct. 2006
Predicting Planets in Known Extra-Solar Planetary Systems II: Testing for Saturn-mass Planets
Recent results have shown that many of the known extrasolar planetary systems
contain regions which are stable for massless test particles. We examine the
possibility that Saturn-mass planets exist in these systems, just below the
detection threshold, and attempt to predict likely orbital parameters for such
unseen planets. To do this, we insert a Saturn-mass planet into the stable
regions of these systems and integrate its orbit for 100 million years. We
conduct 200-600 of these experiments to test parameter space in HD37124,
HD38529, 55Cnc, and HD74156. In HD37124 the global maximum of the survival rate
of Saturns in parameter space is at semimajor axis a = 1.03 AU, eccentricity
e=0.1. In HD38529, only 5% of Saturns are unstable, and the region in which a
Saturn could survive is very broad, centered on 0.5<a<0.6, e<0.2. In 55Cnc we
find three maxima at (a,e) = (1.0 AU, 0.02), (2.0 AU, 0.08), and (3.0 AU,
0.17). In HD74156 we find a broad maximum with = 0.9-1.2 AU, e<=0.15.
Several of these maxima are located in the habitable zones of their parent
stars and are therefore of astrobiological interest. We suggest the possibility
that companions may lie in these locations of parameter space, and encourage
further observational investigation of these systems.Comment: submitted to ApJ 9 pages, 8 figures, 3 table
AC-Tolerant Multifilament Coated Conductors
We report the magnetization losses in an experimental multifilament coated
conductor. A 4 mm wide and 10 cm long YBCO coated conductor was subdivided into
eight 0.5 mm wide filaments by laser ablation and subjected to post-ablation
treatment. As the result, the hysteresis loss was reduced, as expected, in
proportion to the width of the filaments. However, the coupling loss was
reduced dramatically, and became practically negligible, in the range of a
sweep rate up to 20 T/s. This represents a drastic improvement on previous
multifilament conductors in which often the coupling losses became equal to the
hysteresis loss at a sweep rate as low as 3-4 T/s. These results demonstrate
that there is an effective and practical way to suppress coupling losses in
coated multifilament conductors.Comment: This paper is based on a talk given at 2006 Applied Superconductivity
Conference in Seattle, WA (August 27-September 1, 2006). To be published in
IEEE Trans. Appl. Superconductivit
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Pictures of life in older age: a quantitative analysis of the lived experience of ageing using the Understanding Society survey
Prison Anger Reduction Programs Evaluation Development Project
This report describes efforts to develop Alaska-specific norms for the Minnesota Multiphasic Personality Inventory (MMPI), using the Megargee offender classification system, for use in program evaluations in Alaska correctional facilities, specifically for evaluation of three pilot anger reduction programs initiated at Alaska Department of Corrections institutions in late 1984/early 1985: (1) Women in Crisis (at Fairbanks Correctional Center); (2) M. E. N., Inc. (at Lemon Creek Correctional Center, Juneau); (3) Bering Sea Women's Group (at Nome Correctional Center). The report provides assessments of the three programs and the correctional centers where they were held and makes recommendations for completing the development of Alaska-specific MMPI-based norms and for the administration of the MMPI as pre- and post-test for measuring psychological changes — particularly in hostility/frustration levels — in participants in anger reduction programs.Alaska Council on Domestic Violence and Sexual AssaultIntroduction /
Section I. History of the Project /
Section II. Psychological Testing /
Section III. Site Assessment — Facilities /
Section IV. Site Assessment — Programs /
Section V. Recommendations /
APPENDICES /
A. Domestic Violence Evaluation Project: Assessment of Programs for Anger Reduction in Incarcerated Alaskan Prisoners [Project proposal] /
B. Letter from Nancy E. Schafer to Barbara Miklos, June 7, 1985 /
C. Site Visits /
D. Criminal Justice Assessment Cervices, Inc.: Experimental MMPI Scales Availabl
Stability Limits in Resonant Planetary Systems
The relationship between the boundaries for Hill and Lagrange stability in
orbital element space is modified in the case of resonantly interacting
planets. Hill stability requires the ordering of the planets to remain constant
while Lagrange stability also requires all planets to remain bound to the
central star. The Hill stability boundary is defined analytically, but no
equations exist to define the Lagrange boundary, so we perform numerical
experiments to estimate the location of this boundary. To explore the effect of
resonances, we consider orbital element space near the conditions in the HD
82943 and 55 Cnc systems. Previous studies have shown that, for non-resonant
systems, the two stability boundaries are nearly coincident. However the Hill
stability formula are not applicable to resonant systems, and our investigation
shows how the two boundaries diverge in the presence of a mean-motion
resonance, while confirming that the Hill and Lagrange boundaries are similar
otherwise. In resonance the region of stability is larger than the domain
defined by the analytic formula for Hill stability. We find that nearly all
known resonant interactions currently lie in this extra stable region, i.e.
where the orbits would be unstable according to the non-resonant Hill stability
formula. This result bears on the dynamical packing of planetary systems,
showing how quantifying planetary systems' dynamical interactions (such as
proximity to the Hill-stability boundary) provides new constraints on planet
formation models.Comment: 13 pages, 3 figures, 2 tables, accepted for publication in ApJ
Letters. A version with full resolution figures is available at
http://www.lpl.arizona.edu/~rory/research/xsp/resstab.pd
On a q-analogue of the multiple gamma functions
A -analogue of the multiple gamma functions is introduced, and is shown to
satisfy the generalized Bohr-Morellup theorem. Furthermore we give some
expressions of these function.Comment: 8 pages, AMS-Late
Hadron Loops: General Theorems and Application to Charmonium
In this paper we develop a formalism for incorporating hadron loops in the
quark model. We derive expressions for mass shifts, continuum components and
mixing amplitudes of "quenched" quark model states due to hadron loops, as
perturbation series in the valence-continuum coupling Hamiltonian. We prove
three general theorems regarding the effects of hadron loops, which show that
given certain constraints on the external "bare" quark model states, the
valence-continuum coupling, and the hadrons summed in the loops, the following
results hold: (1) The loop mass shifts are identical for all states within a
given N,L multiplet. (2) These states have the same total open-flavor decay
widths. (3) Loop-induced valence configuration mixing vanishes provided that
{\L}_i \neq \L_f or . The charmonium system is used as a
numerical case study, with the decay model providing the
valence-continuum coupling. We evaluate the mass shifts and continuum mixing
numerically for all 1S, 1P and 2S charmonium valence states due to loops of D,
D, D and D meson pairs. We find that the mass shifts are quite
large, but are numerically similar for all the low-lying charmonium states, as
suggested by the first theorem. Thus, loop mass shifts may have been "hidden"
in the valence quark model by a change of parameters. The two-meson continuum
components of the physical charmonium states are also found to be large,
creating challenges for the interpretation of the constituent quark model.Comment: 10 pages, 1 ps figure. Typos corrected; discussion of psi-eta_c mass
splitting added, published versio
An Alternative Model for Analyzing the Physician-Hospital Relationship in Rural Areas
We introduce a modeling framework called Transaction Cost Economics to help decision makers in rural health care markets choose among alternative organizational relationships in order to more cost-effectively deliver healthcare services. In particular, the hospital-physician relationship is analyzed and the transactional attributes, institutional environment, and market characteristics are identified as key variables influencing the organizational relationship between hospital and physician. As asset specfic investments are made by either the hospital or physician, vertically integrated relationships are more likely to occur. The degree of remoteness of rural areas is also considered to affect the impact of these asset-specific investments.Community/Rural/Urban Development, Health Economics and Policy,
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