5,240 research outputs found
Characterization of low loss microstrip resonators as a building block for circuit QED in a 3D waveguide
Here we present the microwave characterization of microstrip resonators made
from aluminum and niobium inside a 3D microwave waveguide. In the low
temperature, low power limit internal quality factors of up to one million were
reached. We found a good agreement to models predicting conductive losses and
losses to two level systems for increasing temperature. The setup presented
here is appealing for testing materials and structures, as it is free of wire
bonds and offers a well controlled microwave environment. In combination with
transmon qubits, these resonators serve as a building block for a novel circuit
QED architecture inside a rectangular waveguide
Geoquímica y sistemática isotópica de rocas metamórficas del Paleozoico inferior. Noroeste de Argentina y Norte de Chile (21°-27° S)
Más del 95% de los afloramientos del basamento metamórfico del Paleozoico inferior en el Noroeste de A rgentina y Norte de Chile están compuestos por rocas félsicas. Los contenidos de elementos mayores, trazas y las composiciones isotópicas de Pb, Rb-Sr y Sm-Nd son típicos de las rocas que conforman la corteza superior. Las edades modelos Sm-Nd de las rocas estudiadas son de ca 1.8 Ga. Estas rocas han sido afectadas por un evento principal de metamorfismo del Paleozoico temprano (ca. 500 Ma).
Se considera que el reciclado de la corteza, con un importante evento de metamorfismo durante el Paleozoico temprano, es el proceso dominante en la generación de muchos de los magmas con composiciones graníticas originados desde el Paleozoico temprano hasta el Reciente.
Las espesas secuencias sedimentarias ordovícicas son derivadas también de esa misma corteza en común. Los xenolitos félsicos de la corteza inferior extraídos por el magmatismo perteneciente al sistema del Rift Salta, son muy similares composicionalmente al basamento del Paleozoico inferior. Se estima que la composición de la corteza desde la parte superior hasta la inferior sería principalmente félsica.
Las rocas máficas tienen muy poco volumen y forman principalmente diques. Sus edades modelos Sm-Nd revelan dos grupos, uno con edades de ca 1.8 Ga y otro con edades de ca £ 1.0 Ga No ha sido posible realizar una interpretación ajustada del ambiente geodinámico en donde se ha desarrollado este magmatismo básico.Felsic rocks comprise more than 95% of the outcropping Early Paleozoic metamorphic basement. Their major and trace element contents and Pb, Rb-Sr and Sm-Nd isotope compositions are typical for upper crustal rocks. Sm-Nd model ages are ca 1.8 Ga. The principal ages of high-grade metamorphism is Early Paleozoic (ca 500 Ma).
Recycling of this crust is the dominating process in the formation of granitoid magmatic rocks from Early Paleozoic to Recent. Ordovician sediments are also derivates of this crust. Felsic lower crustal xenoliths from the Salta Rift system are compositionally very similar compared to the early Paleozoic basement. The crustal composition from top to the bottom seems mainly felsic.
Early Paleozoic mafic rocks are of minor volume and form mainly dikes. Their Sm-Nd model ages reveal two groups; one with ages of ca 1.8 Ga another with ages of £ 1.0 Ga. A meaningful interpretation of their geodynamic setting is not possible
49Cr: Towards full spectroscopy up to 4 MeV
The nucleus 49Cr has been studied analysing gamma-gamma coincidences in the
reaction 46Ti(alpha,n)49Cr at the bombarding energy of 12 MeV. The level scheme
has been greatly extended at low excitation energy and several new lifetimes
have been determined by means of the Doppler Shift Attenuation Method.
Shell model calculations in the full pf configuration space reproduce well
negative-parity levels. Satisfactory agreement is obtained for positive parity
levels by extending the configuration space to include a nucleon-hole either in
the 1d3/2 or in the 2s1/2 orbitals.
A nearly one-to-one correspondence is found between experimental and
theoretical levels up to an excitation energy of 4 MeV.
Experimental data and shell model calculations are interpreted in terms of
the Nilsson diagram and the particle-rotor model, showing the strongly coupled
nature of the bands in this prolate nucleus. Nine values of K(pi) are proposed
for the levels observed in this experiment.
As a by-result it is shown that the values of the experimental magnetic
moments in 1f7/2 nuclei are well reproduced without quenching the nucleon
g-factors.Comment: 13 pages, 8 figure
Accelerating Neoproterozoic research through scientific drilling
No abstract available
coupling determined beyond the chiral limit
Within the conventional QCD sum rules, we calculate the coupling
constant, , beyond the chiral limit using two-point correlation
function with a pion. We consider the Dirac structure, , at
order, which has clear dependence on the PS and PV coupling schemes
for the pion-nucleon interactions. For a consistent treatment of the sum rule,
we include the linear terms in quark mass as they constitute the same chiral
order as . Using the PS coupling scheme for the pion-nucleon
interaction, we obtain , which is very close to the
empirical coupling. This demonstrates that going beyond the chiral
limit is crucial in determining the coupling and the pseudoscalar coupling
scheme is preferable from the QCD point of view.Comment: 8 pages, revtex, some errors are corrected, substantially revise
Experimental setup for camera-based measurements of electrically and optically stimulated luminescence of silicon solar cells and wafers
We report in detail on the luminescence imaging setup developed within the last years in our laboratory. In this setup, the luminescence emission of silicon solar cells or silicon wafers is analyzed quantitatively. Charge carriers are excited electrically (electroluminescence) using a power supply for carrier injection or optically (photoluminescence) using a laser as illumination source. The luminescence emission arising from the radiative recombination of the stimulated charge carriers is measured spatially resolved using a camera. We give details of the various components including cameras, optical filters for electro- and photo-luminescence, the semiconductor laser and the four-quadrant power supply. We compare a silicon charged-coupled device (CCD) camera with a back-illuminated silicon CCD camera comprising an electron multiplier gain and a complementary metal oxide semiconductor indium gallium arsenide camera. For the detection of the luminescence emission of silicon we analyze the dominant noise sources along with the signal-to-noise ratio of all three cameras at different operation conditions. © 2011 American Institute of Physics
The ZEUS Forward Plug Calorimeter with Lead-Scintillator Plates and WLS Fiber Readout
A Forward Plug Calorimeter (FPC) for the ZEUS detector at HERA has been built
as a shashlik lead-scintillator calorimeter with wave length shifter fiber
readout. Before installation it was tested and calibrated using the X5 test
beam facility of the SPS accelerator at CERN. Electron, muon and pion beams in
the momentum range of 10 to 100 GeV/c were used. Results of these measurements
are presented as well as a calibration monitoring system based on a Co
source.Comment: 38 pages (Latex); 26 figures (ps
Measurements of branching fraction ratios and CP-asymmetries in suppressed B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^- decays
We report the first reconstruction in hadron collisions of the suppressed
decays B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^-, sensitive to the
CKM phase gamma, using data from 7 fb^-1 of integrated luminosity collected by
the CDF II detector at the Tevatron collider. We reconstruct a signal for the
B^- -> D(-> K^+ pi^-)K^- suppressed mode with a significance of 3.2 standard
deviations, and measure the ratios of the suppressed to favored branching
fractions R(K) = [22.0 \pm 8.6(stat)\pm 2.6(syst)]\times 10^-3, R^+(K) =
[42.6\pm 13.7(stat)\pm 2.8(syst)]\times 10^-3, R^-(K)= [3.8\pm 10.3(stat)\pm
2.7(syst]\times 10^-3, as well as the direct CP-violating asymmetry A(K) =
-0.82\pm 0.44(stat)\pm 0.09(syst) of this mode. Corresponding quantities for
B^- -> D(-> K^+ pi^-)pi^- decay are also reported.Comment: 8 pages, 1 figure, accepted by Phys.Rev.D Rapid Communications for
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