24,303 research outputs found
Status of the ultra‐cold polarized jet for NEPTUN and NETPUN‐A at UNK
After tests of the prototype ultra‐cold polarized jet, the jet assembly for use in the experiment NEPTUN‐A at UNK is being designed, built, and tested at the University of Michigan. Planned improvements include a more powerful refrigerator, a 12 T high‐gradient solenoid, and a superconducting focusing sextupole. In this talk the design and present status are described.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87510/2/32_1.pd
Tests of a prototype large-bore, low-power 2↔42↔4 RF transition unit
The Michigan ultra-cold polarized hydrogen jet requires a 2↔42↔4 RF transition unit with a large bore, low power input for cryogenic operation, and a static magnetic field parallel to the atomic beam. The prototype unit has a cylindrical RF cavity with clear bore of 7 cm, loaded with a dielectric ring. Transition efficiency has been measured using a maser run in transient mode, by observing free induction decay. In tests on a room-temperature polarized beam, for static fields of under 100 G, we have measured efficiencies of 95% with less than 100 mW of RF power. This work is supported by a grant from the U.S. Department of Energy. © 1998 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87440/2/475_1.pd
Penentuan Jumlah Teller yang Optimal dengan Metode Antrian di PT Bank Haga
This article presents the optimization of the number of tellers at the service counter at PT BANK Haga. Its done by comparing the some alternatives related to the number of tellers employed. Conclusion indicates that optimal condition is that 5 tellers at Abdul Muis Branch and 4 tellers at Daan Mogot Branch
Stochastic superspace phenomenology at the Large Hadron Collider
We analyse restrictions on the stochastic superspace parameter space arising
from 1 fb of LHC data, and bounds on sparticle masses, cold dark matter
relic density and the branching ratio of the process . A region of parameter space consistent with these limits is found where
the stochasticity parameter, \xi, takes values in the range -2200 GeV < \xi <
-900 GeV, provided the cutoff scale is GeV.Comment: 9 pages, 13 figure
A Classical Density-Functional Theory for Describing Water Interfaces
We develop a classical density functional for water which combines the White
Bear fundamental-measure theory (FMT) functional for the hard sphere fluid with
attractive interactions based on the Statistical Associating Fluid Theory
(SAFT-VR). This functional reproduces the properties of water at both long and
short length scales over a wide range of temperatures, and is computationally
efficient, comparable to the cost of FMT itself. We demonstrate our functional
by applying it to systems composed of two hard rods, four hard rods arranged in
a square and hard spheres in water
Characterizing Multi-planet Systems with Classical Secular Theory
Classical secular theory can be a powerful tool to describe the qualitative
character of multi-planet systems and offer insight into their histories. The
eigenmodes of the secular behavior, rather than current orbital elements, can
help identify tidal effects, early planet-planet scattering, and dynamical
coupling among the planets, for systems in which mean-motion resonances do not
play a role. Although tidal damping can result in aligned major axes after all
but one eigenmode have damped away, such alignment may simply be fortuitous. An
example of this is 55 Cancri (orbital solution of Fischer et al., 2008) where
multiple eigenmodes remain undamped. Various solutions for 55 Cancri are
compared, showing differing dynamical groupings, with implications for the
coupling of eccentricities and for the partitioning of damping among the
planets. Solutions for orbits that include expectations of past tidal evolution
with observational data, must take into account which eigenmodes should be
damped, rather than expecting particular eccentricities to be near zero.
Classical secular theory is only accurate for low eccentricity values, but
comparison with other results suggests that it can yield useful qualitative
descriptions of behavior even for moderately large eccentricity values, and may
have advantages for revealing underlying physical processes and, as large
numbers of new systems are discovered, for triage to identify where more
comprehensive dynamical studies should have priority.Comment: Published in Celestial Mechanics and Dynamical Astronomy, 25 pages,
10 figure
Kink-induced symmetry breaking patterns in brane-world SU(3)^3 trinification models
The trinification grand unified theory (GUT) has gauge group SU(3)^3 and a
discrete symmetry permuting the SU(3) factors. In common with other GUTs, the
attractive nature of the fermionic multiplet assignments is obviated by the
complicated multi-parameter Higgs potential apparently needed for
phenomenological reasons, and also by vacuum expectation value (VEV)
hierarchies within a given multiplet. This motivates the rigorous consideration
of Higgs potentials, symmetry breaking patterns and alternative symmetry
breaking mechanisms in models with this gauge group. Specifically, we study the
recently proposed ``clash of symmetries'' brane-world mechanism to see if it
can help with the symmetry breaking conundrum. This requires a detailed
analysis of Higgs potential global minima and kink or domain wall solutions
interpolating between the disconnected global minima created through
spontaneous discrete symmetry breaking. Sufficiently long-lived metastable
kinks can also be considered. We develop what we think is an interesting,
albeit speculative, brane-world scheme whereby the hierarchical symmetry
breaking cascade, trinification to left-right symmetry to the standard model to
colour cross electromagnetism, may be induced without an initial hierarchy in
vacuum expectation values. Another motivation for this paper is simply to
continue the exploration of the rich class of kinks arising in models that are
invariant under both discrete and continuous symmetries.Comment: 12 pages, RevTex, references adde
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