13,046 research outputs found
The Kingdom of Heaven or the New Age
Matthew 25:1-13. Sermon delivered at the chapel, Conrad Grebel College, Univ of Waterloo, November 13, 1996
Witnessing the Growth of the Nearest Galaxy Cluster: Thermodynamics of the Virgo Cluster Outskirts
We present results from Suzaku Key Project observations of the Virgo Cluster,
the nearest galaxy cluster to us, mapping its X-ray properties along four long
`arms' extending beyond the virial radius. The entropy profiles along all four
azimuths increase with radius, then level out beyond , while the
average pressure at large radii exceeds Planck Sunyaev-Zel'dovich measurements.
These results can be explained by enhanced gas density fluctuations (clumping)
in the cluster's outskirts. Using a standard Navarro, Frenk and White (1997)
model, we estimate a virial mass, radius, and concentration parameter of
M, kpc, and , respectively. The inferred cumulative baryon fraction exceeds
the cosmic mean at along the major axis, suggesting enhanced
gas clumping possibly sourced by a candidate large-scale structure filament
along the north-south direction. The Suzaku data reveal a large-scale sloshing
pattern, with two new cold fronts detected at radii of 233 kpc and 280 kpc
along the western and southern arms, respectively. Two high-temperature regions
are also identified 1 Mpc towards the south and 605 kpc towards the west of
M87, likely representing shocks associated with the ongoing cluster growth.
Although systematic uncertainties in measuring the metallicity for low
temperature plasma remain, the data at large radii appear consistent with a
uniform metal distribution on scales of kpc and larger,
providing additional support for the early chemical enrichment scenario driven
by galactic winds at redshifts of 2-3.Comment: submitted to MNRA
A uniform metallicity in the outskirts of massive, nearby galaxy clusters
Suzaku measurements of a homogeneous metal distribution of Solar
in the outskirts of the nearby Perseus cluster suggest that chemical elements
were deposited and mixed into the intergalactic medium before clusters formed,
likely over 10 billion years ago. A key prediction of this early enrichment
scenario is that the intracluster medium in all massive clusters should be
uniformly enriched to a similar level. Here, we confirm this prediction by
determining the iron abundances in the outskirts () of a sample
of ten other nearby galaxy clusters observed with Suzaku for which robust
measurements based on the Fe-K lines can be made. Across our sample the iron
abundances are consistent with a constant value,
Solar ( for 25 degrees of freedom). This is remarkably similar to
the measurements for the Perseus cluster of Solar,
using the Solar abundance scale of Asplund et al. (2009).Comment: accepted for publication in MNRA
Observation of Scalar Aharonov-Bohm Effect with Longitudinally Polarized Neutrons
We have carried out a neutron interferometry experiment using longitudinally polarized neutrons to observe the scalar Aharonov-Bohm effect. The neutrons inside the interferometer are polarized parallel to an applied pulsed magnetic field B(t). The pulsed B field is spatially uniform so it exerts no force on the neutrons. Its direction also precludes the presence of any classical torque to change the neutron polarization
The Economics of the Joint Antitrust Dissents of Justices Harlan and Stewart
Professor Werner presents a chronological study of the antitrust dissents authored by Justices Harlan and Stewart in an attempt to identify the minority rationale which may guide the Court\u27s future antitrust decisions. Analyzing these dissenting opinions against the economic criteria of industry structure, conduct and performance, Professor Werner concludes that the dissenters focus primarily on industry performance while showing some concern for the structure of the industry. The author views the dissenters as strict constructionists and believes that their conservative economic orientation may emerge as the antitrust philosophy of the Nixon appointees to the United States Supreme Court
Scalar Aharonov-Bohm effect with longitudinally polarized neutrons
In the scalar Aharonov-Bohm effect, a charged particle (electron) interacts with the scalar electrostatic potential U in the field-free (i.e., force-free) region inside an electrostatic cylinder (Faraday cage). Using a perfect single-crystal neutron interferometer we have performed a “dual” scalar Aharonov-Bohm experiment by subjecting polarized thermal neutrons to a pulsed magnetic field. The pulsed magnetic field was spatially uniform, precluding any force on the neutrons. Aligning the direction of the pulsed magnetic field to the neutron magnetic moment also rules out any classical torque acting to change the neutron polarization. The observed phase shift is purely quantum mechanical in origin. A detailed description of the experiment, performed at the University of Missouri Research Reactor, and its interpretation is given in this paper
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