5,370 research outputs found
Study of thin film large area photovoltaic solar energy converter First quarterly report, 25 Oct. 1965 - 24 Jan. 1966
Cadmium sulfide thin film photovoltaic cell for large area solar energy converte
Study of thin film large area photovoltaic solar energy converter Final report
Thin film large area cadmium sulfide solar cell
Study of thin film large area photovoltaic solar energy converter Third quarterly report, 25 Apr. - 24 Jul. 1966
Cadmium sulfide-thin film large area photovoltaic solar energy converter - plastic substrate cell fabrication and stability testing under various conditions of temperature and humidit
Development of cadmium sulfide thin film photovoltaic cells third quarterly report, apr. 15 - jul. 14, 1965
Cadmium sulfide thin film photovoltaic cells - cadmium sulfide film evaporation, cell testing, improvement, and stability, and plastic and metal substrate cell
Study of thin film large area photovoltaic solar energy converter Second quarterly report, 25 Feb. - 24 May 1966
Cadmium sulfide thin film solar cell developmen
CdS solar cell development Interim technical report
Cadmium sulfide solar cell design criteri
Temperature Anisotropies and Distortions Induced by Hot Intracluster Gas on the Cosmic Microwave Background
The power spectrum of temperature anisotropies induced by hot intracluster
gas on the cosmic background radiation is calculated. For low multipoles it
remains constant while at multipoles above it is exponentially damped.
The shape of the radiation power spectrum is almost independent of the average
intracluster gas density profile, gas evolution history or clusters virial
radii; but the amplitude depends strongly on those parameters and could be as
large as 20% that of intrinsic contribution. The exact value depends on the
global properties of the cluster population and the evolution of the
intracluster gas. The distortion on the Cosmic Microwave Background black body
spectra varies in a similar manner. The ratio of the temperature anisotropy to
the mean Comptonization parameters is shown to be almost independent of the
cluster model and, in first approximation, depends only on the number density
of clusters.Comment: 10 pages, Latex, 3 figures; to be published in Ap
Catalog of Galaxy Morphology in Four Rich Clusters: Luminosity Evolution of Disk Galaxies at 0.33<z<0.83
Hubble Space Telescope (HST) imaging of four rich, X-ray luminous, galaxy
clusters (0.33<z<0.83) is used to produce quantitative morphological
measurements for galaxies in their fields. Catalogs of these measurements are
presented for 1642 galaxies brighter than F814W(AB)=23.0 . Galaxy luminosity
profiles are fitted with three models: exponential disk, de Vaucouleurs bulge,
and a disk-plus-bulge hybrid model. The best fit is selected and produces a
quantitative assessment of the morphology of each galaxy: the principal
parameters derived being B/T, the ratio of bulge to total luminosity, the scale
lengths and half-light radii, axial ratios, position angles and surface
brightnesses of each component. Cluster membership is determined using a
statistical correction for field galaxy contamination, and a mass normalization
factor (mass within boundaries of the observed fields) is derived for each
cluster. In the present paper, this catalog of measurements is used to
investigate the luminosity evolution of disk galaxies in the rich-cluster
environment. Examination of the relations between disk scale-length and central
surface brightness suggests, under the assumption that these clusters represent
a family who share a common evolutionary history and are simply observed at
different ages, that there is a dramatic change in the properties of the small
disks (h < 2 kpc). This change is best characterized as a change in surface
brightness by about 1.5 magnitude between z=0.3 and z=0.8 with brighter disks
at higher redshifts.Comment: 53 pages, including 13 figures and 7 tables. Accepted for publication
in the Astrophysical Journal Supplement Serie
Chandra Observations of low velocity dispersion groups
Deviations of galaxy groups from cluster scaling relations can be understood
in terms of an excess of entropy in groups. The main effect of this excess is
to reduce the density and thus luminosity of the intragroup gas. Given this,
groups should also should show a steep relationship between X-ray luminosity
and velocity dispersion. However, previous work suggests that this is not the
case with many measuring slopes flatter than the cluster relation.
Examining the group L_X:\sigma relation shows that much of the flattening is
caused by a small subset of groups which show very high X-ray luminosities for
their velocity dispersions (or vice versa).
Detailed Chandra study of two such groups shows that earlier ROSAT results
were subject to significant (~30-40%) point source contamination, but confirm
that a significant hot IGM is present in these groups, although these are two
of the coolest systems in which intergalactic X-ray emission has been detected.
Their X-ray properties are shown to be broadly consistent with those of other
galaxy groups, although the gas entropy in NGC 1587 is unusually low, and its
X-ray luminosity correspondingly high for its temperature, compared to most
groups.
This leads us to suggest that the velocity dispersion in these systems has
been reduced in some way, and we consider how this might have come about.Comment: Accepted for publication in Ap
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