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Evidence of convection as a major source of condensation nuclei in the northern midlatitude upper troposphere
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Impact of aircraft emissions on reactive nitrogen over the North Atlantic Flight Corridor region
PSY5 Comparing Brentuximab Vedotin Overall Survival Data to Standard of Care in Patients With Relapsed/Refractory Hodgkin Lymphoma (HL) Post-Autologous Stem Cell Transplant (ASCT)
Ultraviolet relaxation dynamics of aniline, N, N-dimethylaniline and 3,5-dimethylaniline at 250 nm
Quadrature Observations of Wave and Non-Wave Components and Their Decoupling in an Extreme-Ultraviolet Wave Event
We report quadrature observations of an extreme-ultraviolet (EUV) wave event
on 2011 January 27 obtained by the Extreme Ultraviolet Imager (EUVI) onboard
\emph{Solar Terrestrial Relations Observatory} (\emph{STEREO}), and the
Atmospheric Imaging Assembly (AIA) onboard the \emph{Solar Dynamics
Observatory} (\emph{SDO}). Two components are revealed in the EUV wave event. A
primary front is launched with an initial speed of 440 km s. It
appears significant emission enhancement in the hotter channel but deep
emission reduction in the cooler channel. When the primary front encounters a
large coronal loop system and slows down, a secondary much fainter front
emanates from the primary front with a relatively higher starting speed of
550 km s. Afterwards the two fronts propagate independently with
increasing separation. The primary front finally stops at a magnetic
separatrix, while the secondary front travels farther before it fades out. In
addition, upon the arrival of the secondary front, transverse oscillations of a
prominence are triggered. We suggest that the two components are of different
natures. The primary front belongs to a non-wave coronal mass ejection (CME)
component, which can be reasonably explained with the field-line stretching
model. The multi-temperature behavior may be caused by considerable heating due
to the nonlinear adiabatic compression on the CME frontal loop. For the
secondary front, most probably it is a linear fast-mode magnetohydrodynamic
(MHD) wave that propagates through a medium of the typical coronal temperature.
X-ray and radio data provide us with complementary evidence in support of the
above scenario.Comment: 21 pages, 8 figures, accepted for publication in Ap
The multifrequency Siberian Radioheliograph
The 10-antenna prototype of the multifrequency Siberian radioheliograph is
described. The prototype consists of four parts: antennas with broadband
front-ends, analog back-ends, digital receivers and a correlator. The prototype
antennas are mounted on the outermost stations of the Siberian Solar Radio
Telescope (SSRT) array. A signal from each antenna is transmitted to a workroom
by an analog fiber optical link, laid in an underground tunnel. After mixing,
all signals are digitized and processed by digital receivers before the data
are transmitted to the correlator. The digital receivers and the correlator are
accessible by the LAN. The frequency range of the prototype is from 4 to 8 GHz.
Currently the frequency switching observing mode is used. The prototype data
include both circular polarizations at a number of frequencies given by a list.
This prototype is the first stage of the multifrequency Siberian
radioheliograph development. It is assumed that the radioheliograph will
consist of 96 antennas and will occupy stations of the West-East-South subarray
of the SSRT. The radioheliograph will be fully constructed in autumn of 2012.
We plan to reach the brightness temperature sensitivity about 100 K for the
snapshot image, a spatial resolution up to 13 arcseconds at 8 GHz and
polarization measurement accuracy about a few percent.
First results with the 10-antenna prototype are presented of observations of
solar microwave bursts. The prototype abilities to estimate source size and
locations at different frequencies are discussed
Suppression of Superconducting Critical Current Density by Small Flux Jumps in Thin Films
By doing magnetization measurements during magnetic field sweeps on thin
films of the new superconductor , it is found that in a low temperature
and low field region small flux jumps are taking place. This effect strongly
suppresses the central magnetization peak leading to reduced nominal
superconducting critical current density at low temperatures. A borderline for
this effect to occur is determined on the field-temperature (H-T) phase
diagram. It is suggested that the small size of the flux jumps in films is due
to the higher density of small defects and the relatively easy thermal
diffusion in thin films in comparison with bulk samples.Comment: 7 figures Phys. Rev. B accepted scheduled issue: 01 Feb 200
Evaluation of selected chemical processes for production of low-cost silicon phase 2. silicon material task, low-cost silicon solar array project
Progress from October 1, 1977, through December 31, 1977, is reported in the design of the 50 MT/year experimental facility for the preparation of high purity silicon by the zinc vapor reduction of silicon tetrachloride in a fluidized bed of seed particles to form a free flowing granular product
Gaussian quantum marginal problem
The quantum marginal problem asks what local spectra are consistent with a
given spectrum of a joint state of a composite quantum system. This setting,
also referred to as the question of the compatibility of local spectra, has
several applications in quantum information theory. Here, we introduce the
analogue of this statement for Gaussian states for any number of modes, and
solve it in generality, for pure and mixed states, both concerning necessary
and sufficient conditions. Formally, our result can be viewed as an analogue of
the Sing-Thompson Theorem (respectively Horn's Lemma), characterizing the
relationship between main diagonal elements and singular values of a complex
matrix: We find necessary and sufficient conditions for vectors (d1, ..., dn)
and (c1, ..., cn) to be the symplectic eigenvalues and symplectic main diagonal
elements of a strictly positive real matrix, respectively. More physically
speaking, this result determines what local temperatures or entropies are
consistent with a pure or mixed Gaussian state of several modes. We find that
this result implies a solution to the problem of sharing of entanglement in
pure Gaussian states and allows for estimating the global entropy of
non-Gaussian states based on local measurements. Implications to the actual
preparation of multi-mode continuous-variable entangled states are discussed.
We compare the findings with the marginal problem for qubits, the solution of
which for pure states has a strikingly similar and in fact simple form.Comment: 18 pages, 1 figure, material added, references updated, except from
figure identical with version to appear in Commun. Math. Phy
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