547 research outputs found
Putting it in Writing: Examining the Link between Higher Education Institution Performance Rankings, Best Places to Work, and Emphasis on Human Resources in Mission Statements
This study examined at the content of vision statements, mission statements, and strategic plans for three groups of higher education institutions (HEIs). The focus of this analysis was to determine if an emphasis on the interests and welfare of employees was included in these statements. In addition, the Top 100 Best Colleges from the 2012 U.S. News & World Report rankings were compared to a random selection of HEIs. The results indicate that the externally ranked schools had a higher number of statements highlighting the welfare of their workforce in their strategic documents, thus affirming the importance of employees
Angular anisotropy of the fusion-fission and quasifission fragments
The anisotropy in the angular distribution of the fusion-fission and
quasifission fragments for the O+U, F+Pb and
S+Pb reactions is studied by analyzing the angular momentum
distributions of the dinuclear system and compound nucleus which are formed
after capture and complete fusion, respectively. The orientation angles of
axial symmetry axes of colliding nuclei to the beam direction are taken into
account for the calculation of the variance of the projection of the total spin
onto the fission axis. It is shown that the deviation of the experimental
angular anisotropy from the statistical model picture is connected with the
contribution of the quasifission fragments which is dominant in the
S+Pb reaction. Enhancement of anisotropy at low energies in the
O+U reaction is connected with quasifission of the dinuclear
system having low temperature and effective moment of inertia.Comment: 17 pages 8 figures. Submitted to Euro. Phys. Jour.
Spin-size disorder model for granular superconductors with charging effects
A quantum pseudo-spin model with random spin sizes is introduced to study the
effects of charging-energy disorder on the superconducting transition in
granular superconducting materials. Charging-energy effects result from the
small electrical capacitance of the grains when the Coulomb charging energy is
comparable to the Josephson coupling energy. In the pseudo-spin model,
randomness in the spin size is argued to arise from the inhomogeneous
grain-size distribution. For a particular bimodal spin-size distribution, the
model describes percolating granular superconductors. A mean-field theory is
developed to obtain the phase diagram as a function of temperature, average
charging energy and disorder.Comment: 4 pages, 2 figure
Two Pseudobulges in the "Boxy Bulge" Galaxy NGC 5746
Galaxy formation and growth under the {\Lambda}CDM paradigm is expected to
proceed in a hierarchical, bottom-up fashion by which small galaxies grow into
large galaxies; this mechanism leaves behind large "classical bulges"
kinematically distinct from "pseudobulges" grown by internal, secular
processes. We use archival data (Spitzer 3.6 \mum wavelength, Hubble Space
Telescope H-band, Two Micron All Sky Survey Ks-band, and Sloan Digital Sky
Survey gri-band) to measure composite minor- and major-axis surface brightness
profiles of the almost-edgeon spiral galaxy NGC 5746. These light profiles span
a large range of radii and surface brightnesses to reveal an inner, high
surface brightness stellar component that is distinct from the well-known boxy
bulge. It is well fitted by S\'ersic functions with indices n = 0.99 \pm 0.08
and 1.17 \pm 0.24 along the minor and major axes, respectively. Since n < 2, we
conclude that this innermost component is a secularly-evolved pseudobulge that
is distinct from the boxy pseudobulge. This inner pseduobulge makes up 0.136
\pm 0.019 of the total light of the galaxy. It is therefore considerably less
luminous than the boxy structure, which is now understood to be a bar seen
nearly end-on. The infrared imagery shows further evidence for secular
evolution in the form of a bright inner ring of inner radius 9.1 kpc and width
1.6 kpc. NGC 5746 is therefore a giant, pure-disk SB(r)bc galaxy with no sign
of a merger-built bulge. We do not understand how such galaxies form in a
{\Lambda}CDM universe.Comment: 23 pages, 7 figures, 2 tables; accepted for publication in Ap
Submillimeter Observations of Dense Clumps in the Infrared Dark Cloud G049.40-00.01
We obtained 350 and 850 micron continuum maps of the infrared dark cloud
G049.40-00.01. Twenty-one dense clumps were identified within G049.40-00.01
based on the 350 micron continuum map with an angular resolution of about 9.6".
We present submillimeter continuum maps and report physical properties of the
clumps. The masses of clumps range from 50 to 600 M_sun. About 70% of the
clumps are associated with bright 24 micron emission sources, and they may
contain protostars. The most massive two clumps show extended, enhanced 4.5
micron emission indicating vigorous star-forming activity. The clump size-mass
distribution suggests that many of them are forming high mass stars.
G049.40-00.01 contains numerous objects in various evolutionary stages of star
formation, from pre-protostellar clumps to HII regions.Comment: 6 pages, 3 figures; accepted for publication in Ap
Infrared Properties of a Complete Sample of Star-Forming Dwarf Galaxies
We present a study of a large, statistically complete sample of star-forming
dwarf galaxies using mid-infrared observations from the {\it Spitzer Space
Telescope}. The relationships between metallicity, star formation rate (SFR)
and mid-infrared color in these systems show that the galaxies span a wide
range of properties. However, the galaxies do show a deficit of 8.0 \um\
polycyclic aromatic hydrocarbon emission as is apparent from the median 8.0
\um\ luminosity which is only 0.004 \lstarf\ while the median -band
luminosity is 0.05 \lstarb. Despite many of the galaxies being 8.0 \um\
deficient, there is about a factor of 4 more extremely red galaxies in the
[3.6] [8.0] color than for a sample of normal galaxies with similar optical
colors. We show correlations between the [3.6] [8.0] color and luminosity,
metallicity, and to a lesser extent SFRs that were not evident in the original,
smaller sample studied previously. The luminosity--metallicity relation has a
flatter slope for dwarf galaxies as has been indicated by previous work. We
also show a relationship between the 8.0 \um\ luminosity and the metallicity of
the galaxy which is not expected given the competing effects (stellar mass,
stellar population age, and the hardness of the radiation field) that influence
the 8.0 \um\ emission. This larger sample plus a well-defined selection
function also allows us to compute the 8.0 \um\ luminosity function and compare
it with the one for the local galaxy population. Our results show that below
10 \solar, nearly all the 8.0 \um\ luminosity density of the local
universe arises from dwarf galaxies that exhibit strong \ha\ emission -- i.e.,
8.0 \um\ and \ha\ selection identify similar galaxy populations despite the
deficit of 8.0 \um\ emission observed in these dwarfs.Comment: 13 pages, 11 figures, Published in Ap
Asteroid Distributions in the Ecliptic
We present analysis of the asteroid surface density distribution of main belt
asteroids (mean perihelion AU) in five ecliptic latitude
fields, -17 \gtsimeq \beta(\degr) \ltsimeq +15, derived from deep
\textit{Large Binocular Telescope} (LBT) band (85% completeness limit mag) and \textit{Spitzer Space Telescope} IRAC 8.0 \micron (80%
completeness limit Jy) fields enabling us to probe the 0.5--1.0
km diameter asteroid population. We discovered 58 new asteroids in the optical
survey as well as 41 new bodies in the \textit{Spitzer} fields. The derived
power law slopes of the number of asteroids per square degree are similar
within each \degr{} ecliptic latitude bin with a mean value of . For the 23 known asteroids detected in all four IRAC channels mean
albedos range from to . No low albedo asteroids
( \ltsimeq 0.1) were detected in the \textit{Spitzer} FLS fields,
whereas in the SWIRE fields they are frequent. The SWIRE data clearly samples
asteroids in the middle and outer belts providing the first estimates of these
km-sized asteroids' albedos. Our observed asteroid number densities at optical
wavelengths are generally consistent with those derived from the Standard
Asteroid Model within the ecliptic plane. However, we find an over density at
\beta \gtsimeq 5\degr{} in our optical fields, while the infrared number
densities are under dense by factors of 2 to 3 at all ecliptic latitudes.Comment: 35 pages including 5 figures, accepted to The Astronomical Journa
Inhibition of Linear Absorption in Opaque Materials Using Phase-Locked Harmonic Generation
We theoretically predict and experimentally demonstrate inhibition of linear absorption for phase and group velocity mismatched second- and third-harmonic generation in strongly absorbing materials, GaAs, in particular, at frequencies above the absorption edge.
A 100-fs pump pulse tuned to 1300 nm generates 650 and 435 nm second- and third-harmonic pulses that propagate across a 450−μm-thick GaAs substrate without being absorbed.
We attribute this to a phase-locking mechanism that causes the pump to trap the harmonics and to impress on them its dispersive properties
- …