784 research outputs found
H. P. Davis Correspondence
Entries include a handwritten letter from Davis suggesting that the Maine Author Collection could include works by the Davis family and the author Patten and typed letters of correspondence from the Maine State Library
RB56-179 Comparative Measurements of Holstein, Ayrshire, Guernsey, and Jersey Females from Birth to Seven Years
Body measurements are important for a proper understanding of how growth takes place in animals. Unfortunately, few growth data other than for weight have been published concerning dairy cattle.
This is a report of measurements of females in the University of Nebraska dairy herd made as part of a long-time growth study. During the period 1922 to 1942 each animal born into the herd was weighed and measured at regular intervals. Presented here are the data for weight, height, length, width, depth, girth and hide thickness for females of the Holstein, Ayrshire, Guernsey, and Jersey breeds. The average body measurements are presented by three-month intervals from birth through 12 months, and by six-month intervals thereafter through 84 months
Kerr black hole quasinormal frequencies
Black-hole quasinormal modes (QNM) have been the subject of much recent
attention, with the hope that these oscillation frequencies may shed some light
on the elusive theory of quantum gravity. We compare numerical results for the
QNM spectrum of the (rotating) Kerr black hole with an {\it exact} formula
Re, which is based on Bohr's correspondence
principle. We find a close agreement between the two. Possible implications of
this result to the area spectrum of quantum black holes are discussed.Comment: 3 pages, 2 figure
Separability of Hamilton-Jacobi and Klein-Gordon Equations in General Kerr-NUT-AdS Spacetimes
We demonstrate the separability of the Hamilton-Jacobi and scalar field
equations in general higher dimensional Kerr-NUT-AdS spacetimes. No restriction
on the parameters characterizing these metrics is imposed.Comment: 4 pages, no figure
Isoscalar dipole strength in ^{208}_{82}Pb_{126}: the spurious mode and the strength in the continuum
Isoscalar dipole (compression) mode is studied first using schematic
harmonic-oscillator model and, then, the self-consistent Hartree-Fock (HF) and
random phase approximation (RPA) solved in coordinate space. Taking ^{208}Pb
and the SkM* interaction as a numerical example, the spurious component and the
strength in the continuum are carefully examined using the sum rules. It is
pointed out that in the continuum calculation one has to use an extremely fine
radial mesh in HF and RPA in order to separate, with good accuracy, the
spurious component from intrinsic excitations.Comment: 19 pages, 2 figure
Does Conservation Planning Matter in a Dynamic and Uncertain World?
We show that while comprehensive reserve network design is best when the entire network can be implemented immediately, when conservation investments must be staged over years, such solutions actually may be sub-optimal in the context of biodiversity loss and uncertainty
Isoscalar Giant Dipole Resonance and Nuclear Matter Incompressibility Coefficient
We present results of microscopic calculations of the strength function,
S(E), and alpha-particle excitation cross sections sigma(E) for the isoscalar
giant dipole resonance (ISGDR). An accurate and a general method to eliminate
the contributions of spurious state mixing is presented and used in the
calculations. Our results provide a resolution to the long standing problem
that the nuclear matter incompressibility coefficient, K, deduced from sigma(E)
data for the ISGDR is significantly smaller than that deduced from data for the
isoscalar giant monopole resonance (ISGMR).Comment: 4 pages using revtex 3.0, 3 postscript figures created by Mathematica
4.
Radiation content of Conformally flat initial data
We study the radiation of energy and linear momentum emitted to infinity by
the headon collision of binary black holes, starting from rest at a finite
initial separation, in the extreme mass ratio limit. For these configurations
we identify the radiation produced by the initially conformally flat choice of
the three geometry. This identification suggests that the radiated energy and
momentum of headon collisions will not be dominated by the details of the
initial data for evolution of holes from initial proper separations
. For non-headon orbits, where the amount of radiation is orders of
magnitude larger, the conformally flat initial data may provide a relative even
better approximation.Comment: 4 pages, 4 figure
Self-consistent description of nuclear compressional modes
Isoscalar monopole and dipole compressional modes are computed for a variety
of closed-shell nuclei in a relativistic random-phase approximation to three
different parametrizations of the Walecka model with scalar self-interactions.
Particular emphasis is placed on the role of self-consistency which by itself,
and with little else, guarantees the decoupling of the spurious
isoscalar-dipole strength from the physical response and the conservation of
the vector current. A powerful new relation is introduced to quantify the
violation of the vector current in terms of various ground-state form-factors.
For the isoscalar-dipole mode two distinct regions are clearly identified: (i)
a high-energy component that is sensitive to the size of the nucleus and scales
with the compressibility of the model and (ii) a low-energy component that is
insensitivity to the nuclear compressibility. A fairly good description of both
compressional modes is obtained by using a ``soft'' parametrization having a
compression modulus of K=224 MeV.Comment: 28 pages and 10 figures; submitted to PR
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