296 research outputs found
Exclusive 16O(γ,π-p) reaction in the Δ resonance region
We report the first exclusive (γ,π-p) measurements on a complex nucleus. The 16O(γ,π-p) reaction was measured at pion laboratory angles of 64° and 120°. Coincident protons were detected over the quasifree angular correlation range using a vertical array of seven plastic scintillator detectors spanning ±33° about the scattering plane. The cross sections are compared to factorized distorted-wave impulse approximation calculations; these provide a good description of the backward angle data, but are in serious disagreement with the forward angle data
Phase fluctuations, dissipation and superfluid stiffness in d-wave superconductors
We study the effect of dissipation on quantum phase fluctuations in d-wave
superconductors. Dissipation, arising from a nonzero low frequency optical
conductivity which has been measured in experiments below , has two
effects: (1) a reduction of zero point phase fluctuations, and (2) a reduction
of the temperature at which one crosses over to classical thermal fluctuations.
For parameter values relevant to the cuprates, we show that the crossover
temperature is still too large for classical phase fluctuations to play a
significant role at low temperature. Quasiparticles are thus crucial in
determining the linear temperature dependence of the in-plane superfluid
stiffness. Thermal phase fluctuations become important at higher temperatures
and play a role near .Comment: Presentation improved, new references added (10 latex pages, 3 eps
figures). submitted to PR
Flamingo Vol. I N 3
Voo-Doo. Untitled. Prose. 1.
Widow. Untitled. Prose. 1.
Tiger. Untitled. Prose. 1.
Purple Cow. Untitled. Prose. 1.
Anonymous. Untitled. Prose. 1.
Life. Untitled. Prose. 2.
Yale Record. Untitled. Prose. 2.
Voo-Doo. Untitled. Prose. 2.
Sour Owl. Untitled. Prose. 2.
Puppet. Untitled. Prose. 2.
Sun Dial. Untitled. Prose. 2.
Anonymous. Untitled. Prose. 2.
Nottingham, Ruth. Teddy . Prose. 5.
Grogan. Untitled. Picture. 7.
Anonymous. Untitled. Prose. 7.
Anonymous. An Easy One . Prose. 7.
Anonymous. How Terrible! Prose. 7.
Anonymous. Untitled. Prose. 7.
Anonymous. Untitled. Poem. 7.
F.H.G. Untitled. Picture. 7.
Wood, J.E.F. When mother Went to College . Prose. 8.
E.D.T. Chicago Corn Exchange . Poem. 8.
Anonymous. Untitled. Prose. 8.
Anonymous. Untitled. Poem. 8.
Anonymous. All But . Prose. 8.
R.D.B. Roscoe to The Rescue . Prose. 9.
Leet, L.D. On The Efficacy of Dreams . Prose. 10.
Orange Ade. The Fable of the Coffin Nailer . Prose. 11.
Orange Ade. Time Wasted . Prose. 11.
Orange Ade. The Americanized Boy . Prose. 11.
Orange Ade. Anything to Oblige . Prose. 11.
Orange Ade. Tit For Tat . Prose. 11.
Orange Ade. Good Alibi . Prose. 11.
Orange Ade. Untitled. Prose. 11.
Grogan. Untitled. Picture. 11.
Lusk, R.G. On The Absurdity of Catching Fish When A-Fishing . Prose. 12.
Anonymous. Co-eds and Plain Eds in 1950 . Picture. 13.
Potter, W.M. Letters of A Japanese Sandman . Prose. 13.
Anonymous. Ex Facultate . Prose. 13.
Anonymous. Untitled. Prose. 13.
R.J.S. An Uplifting Influence . Picture. 13.
Anonymous. Consider the Luxite Girl . Poem. 14.
Anonymous. Shades of Orpheus . Poem. 14.
Anonymous. With The Gospel Team . Poem. 14.
Anonymous. Untitled. Prose. 14.
Anonymous. Untitled. Poem. 14.
Anonymous. A Dirty Trick . Prose. 14.
Taylor, Elsie D. Vestigial Customs . Prose. 15.
Anonymous. Untitled. Prose. 16.
Anonymous. A New version of Anthropology . Prose. 18.
Anonymous. A New version of Anthropology . Picture. 18.
Anonymous. Untitled. Prose. 18.
Funk, Dorothy K. Untitled. Picture. 18.
Anonymous. A Deep one . Prose. 18.
Anonymous. Take His Name . Prose. 18.
Olney, Clarke. The Evolution of An Intellectual . Prose. 19.
Anonymous. Untitled. Prose. 19.
Anonymous. Untitled. Prose. 20.
W.A.W. On Getting Up For Breakfast . Prose. 20.
McCann. Untitled. Picture. 21.
Anonymous. Untitled. Prose. 21.
Anonymous. S.S.S. . Prose. 21.
Anonymous. The Judge Disagreed . Prose. 21.
Anonymous. The Modern Woman . Prose. 21.
Anonymous. Denison Slang in Japan . Prose. 22.
Anonymous. Being Specific . Prose. 22.
Anonymous. Then The Fun Began . Prose. 22.
Anonymous. Then The Fun Began . Prose. 22.
Anonymous. Chess Nuts . Poem. 22.
Anonymous. Chess Nuts . Picture. 22.
Funk, Dorothy K. Untitled. Picture. 22.
Anonymous. Untitled. Prose. 22.
Reel, Virginia. Untitled. Prose. 22.
Anonymous. Untitled. Prose. 23.
Anonymous. Take This to Heart . Prose. 23.
Anonymous. Stepping Out . Picture. 23.
Olney, Clarke. Untitled. Picture. 23.
Anonymous. To Lalage . Prose. 23.
Anonymous. Untitled. Poem. 24.
Anonymous. Description of the Day . Prose. 25.
Anonymous. Untitled. Prose. 25.
Voo-Doo. Good Bizziness . Prose. 26.
Anonymous. Fore! . Prose. 26.
Anonymous. Untitled. Prose. 26.
Brelsford, Ernest C. Souveniring . Prose. 27.
Anonymous. Untitled. Prose. 30.
Burr. Sweet Dreams . Prose. 30.
Jester. Untitled. Prose. 30.
Judge. Untitled. Prose. 30.
Goblin. Untitled. Prose. 30.
Cracker. Sanitation . Poem. 32.
Anonymous. Untitled. Prose. 32.
Jester. Untitled. Prose. 32.
Goblin. Untitled. Prose. 32.
Record. Untitled. Prose. 32.
Linotype. Untitled. Prose. 32.
Holt, Kilburn. The Schemer\u27s Lament . Poem. 7.
Owen, Ernest t. Mother . Poem. 3.
Owen, Ernest T. To--- . Poem. 24
Low-energy p-d Scattering: High Precision Data, Comparisons with Theory, and Phase-Shift Analyses
Angular distributions of sigma(theta), A_y, iT_11, T_20, T_21, and T_22 have
been measured for d-p scattering at E_c.m.=667 keV. This set of high-precision
data is compared to variational calculations with the nucleon-nucleon potential
alone and also to calculations including a three-nucleon (3N) potential.
Agreement with cross-section and tensor analyzing power data is excellent when
a 3N potential is used. However, a comparison between the vector analyzing
powers reveals differences of approximately 40% in the maxima of the angular
distributions which is larger than reported at higher energies for both p-d and
n-d scattering. Single-energy phase-shift analyses were performed on this data
set and a similar data set at E_c.m.=431.3 keV. The role of the different
phase-shift parameters in fitting these data is discussed.Comment: 18 pages, 6 figure
Properties of pattern formation and selection processes in nonequilibrium systems with external fluctuations
We extend the phase field crystal method for nonequilibrium patterning to
stochastic systems with external source where transient dynamics is essential.
It was shown that at short time scales the system manifests pattern selection
processes. These processes are studied by means of the structure function
dynamics analysis. Nonequilibrium pattern-forming transitions are analyzed by
means of numerical simulations.Comment: 15 poages, 8 figure
Proton propagation in nuclei studied in the (e,e’p) reaction
Proton propagation in nuclei was studied using the (e,e’p) reaction in the quasifree region. The coincidence (e,e’p) cross sections were measured at an electron angle of 50.4° and proton angles of 50.1°, 58.2°, 67.9°, and 72.9° for 12C, 27Al, 58Ni, and 181Ta targets at a beam energy of 779.5 MeV. The average outgoing proton energy was 180 MeV. The ratio of the (e,e’p) yield to the simultaneously measured (e,e’) yield was compared to that calculated in the plane-wave impulse approximation and an experimental transmission defined. These experimental transmissions are considerably larger (a factor of ∼2 for 181Ta) than those one would calculate from the free N-N cross sections folded into the nuclear density distribution. A new calculation that includes medium effects (N-N correlations, density dependence of the N-N cross sections and Pauli suppression) accounts for this increase
Two-body decays in the minimal 331 model
The two-body decays of the extra neutral boson Z_2 predicted by the minimal
331 model are analyzed. At the three-level it can decay into standard model
particles as well as exotic quarks and the new gauge bosons predicted by the
model. The decays into a lepton pair are strongly suppressed, with and . In the bosonic
sector, Z_2 would decay mainly into a pair of bilepton gauge bosons, with a
branching ratio below the 0.1 level. The Z_2 boson has thus a leptophobic and
bileptophobic nature and it would decay dominantly into quark pairs. The
anomaly-induced decays and , which occurs
at the one-loop level are studied. It is found that and at most. As for the and decays, with H a relatively light Higgs boson, they
are induced via Z'-Z mixing. It is obtained that
and . We also examine the flavor changing neutral
current decays and , which may have branching
fractions as large as and , respectively, and thus may be of
phenomenological interest.Comment: 14 pages, 3 figures, submitted to Physical Review
Two-proton correlations from 158 AGeV Pb+Pb central collisions
The two-proton correlation function at midrapidity from Pb+Pb central
collisions at 158 AGeV has been measured by the NA49 experiment. The results
are compared to model predictions from static thermal Gaussian proton source
distributions and transport models RQMD and VENUS. An effective proton source
size is determined by minimizing CHI-square/ndf between the correlation
functions of the data and those calculated for the Gaussian sources, yielding
3.85 +-0.15(stat.) +0.60-0.25(syst.) fm. Both the RQMD and the VENUS model are
consistent with the data within the error in the correlation peak region.Comment: RevTeX style, 6 pages, 4 figures, 1 table. More discussion are added
about the structure on the tail of the correlation function. The systematic
error is revised. To appear in Phys. Lett.
Event-by-event fluctuations of average transverse momentum in central Pb+Pb collisions at 158 GeV per nucleon
We present first data on event-by-event fluctuations in the average
transverse momentum of charged particles produced in Pb+Pb collisions at the
CERN SPS. This measurement provides previously unavailable information allowing
sensitive tests of microscopic and thermodynamic collision models and to search
for fluctuations expected to occur in the vicinity of the predicted QCD phase
transition. We find that the observed variance of the event-by-event average
transverse momentum is consistent with independent particle production modified
by the known two-particle correlations due to quantum statistics and final
state interactions and folded with the resolution of the NA49 apparatus. For
two specific models of non-statistical fluctuations in transverse momentum
limits are derived in terms of fluctuation amplitude. We show that a
significant part of the parameter space for a model of isospin fluctuations
predicted as a consequence of chiral symmetry restoration in a non-equilibrium
scenario is excluded by our measurement.Comment: 6 pages, 2 figures, submitted to Phys. Lett.
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