9,900 research outputs found
D0 QCD studies
A number of recent measurements from D0 that can be used to constrain parton
distributions and tune QCD Monte Carlo models are presented. The selection
includes W charge asymmetry, Z+jet event properties, dijet azimuthal
decorrelations and the inclusive jet cross section.Comment: 4 pages, 4 figures; proceedings of the DIS 2006 worksho
Inclusive jet cross section measurement at D0
We present a new preliminary measurement of the inclusive jet cross section
in pp-bar collisions based on a integrated luminosity of about 0.8 fb-1. The
data were acquired using the D0 detector between 2002 and 2005. Jets are
reconstructed using an iterative cone algorithm with radius R_cone = 0.7. The
inclusive jet cross section is presented as a function of transverse jet
momentum and rapidity. Predictions from perturbative QCD in next-to-leading
order, plus threshold corrections in 2-loop accuracy describe the shape in the
transverse jet momentum.Comment: 4 pages, 4 figures; proceedings of the DIS 2006 worksho
Physics of Proximity Josephson Sensor
We study the proximity Josephson sensor (PJS) in both bolometric and
calorimetric operation and optimize it for different temperature ranges between
25 mK and a few Kelvin. We investigate how the radiation power is absorbed in
the sensor and find that the irradiated sensor is typically in a weak
nonequilibrium state. We show in detail how the proximity of the
superconductors affects the device response: for example via changes in
electron-phonon coupling and out-of-equilibrium noise. In addition, we estimate
the applicability of graphene as the absorber material.Comment: 13 pages, 11 figures, submitted to Journal of Applied Physics, v2:
Addition of a new section discussing the radiation coupling to the device,
several minor change
Absorption of heat into a superconductor-normal metal-superconductor junction from a fluctuating environment
We study a diffusive superconductor-normal metal-superconductor junction in
an environment with intrinsic incoherent fluctuations which couple to the
junction through an electromagnetic field. When the temperature of the junction
differs from that of the environment, this coupling leads to an energy transfer
between the two systems, taking the junction out of equilibrium. We describe
this effect in the linear response regime and show that the change in the
supercurrent induced by this coupling leads to qualitative changes in the
current-phase relation and for a certain range of parameters, an increase in
the critical current of the junction. Besides normal metals, similar effects
can be expected also in other conducting weak links.Comment: 5 pages, 4 figures - supplementary information included: 3 pages, 1
figure; minor modifications to the text and Fig. 2, added Ref. 1
Nonequilibrium phenomena in multiple normal-superconducting tunnel heterostructures
Using the nonequilibrium theory of superconductivity with the tunnel
Hamiltonian, we consider a mesoscopic NISINISIN heterostructure, i.e., a
structure consisting of five intermittent normal-metal (N) and superconducting
(S) regions separated by insulating tunnel barriers (I). Applying the bias
voltage between the outer normal electrodes one can drive the central N island
very far from equilibrium. Depending on the resistance ratio of outer and inner
tunnel junctions, one can realize either effective electron cooling in the
central N island or create highly nonequilibrium energy distributions of
electrons in both S and N islands. These distributions exhibit multiple peaks
at a distance of integer multiples of the superconducting chemical potential.
In the latter case the superconducting gap in the S islands is strongly
suppressed as compared to its equilibrium value
Novel Data Acquisition System for Silicon Tracking Detectors
We have developed a novel data acquisition system for measuring tracking
parameters of a silicon detector in a particle beam. The system is based on a
commercial Analog-to-Digital VME module and a PC Linux based Data Acquisition
System. This DAQ is realized with C++ code using object-oriented techniques.
Track parameters for the beam particles were reconstructed using off-line
analysis code and automatic detector position alignment algorithm.
The new DAQ was used to test novel Czochralski type silicon detectors. The
important silicon detector parameters, including signal size distributions and
signal to noise distributions, were successfully extracted from the detector
under study. The efficiency of the detector was measured to be 95 %, the
resolution about 10 micrometers, and the signal to noise ratio about 10.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
(CHEP03), La Jolla, Ca, USA, March 2003, 6 pages, LaTeX, 5 eps figures. PSN
TUGP00
Developing LCA-based benchmarks for sustainable consumption - for and with users
This article presents the development process of a consumer-oriented, illustrative benchmarking tool enabling consumers to use the results of environmental life cycle assessment (LCA) to make informed decisions. Active and environmentally conscious consumers and environmental communicators were identified as key target groups for this type of information. A brochure presenting the benchmarking tool was developed as an participatory, iterative process involving consumer focus groups, stakeholder workshops and questionnaire-based feedback. In addition to learning what works and what does not, detailed suggestions on improved wording and figures were obtained, as well as a wealth of ideas for future applications
Ballistic Josephson junctions in edge-contacted graphene
Hybrid graphene-superconductor devices have attracted much attention since
the early days of graphene research. So far, these studies have been limited to
the case of diffusive transport through graphene with poorly defined and modest
quality graphene-superconductor interfaces, usually combined with small
critical magnetic fields of the superconducting electrodes. Here we report
graphene based Josephson junctions with one-dimensional edge contacts of
Molybdenum Rhenium. The contacts exhibit a well defined, transparent interface
to the graphene, have a critical magnetic field of 8 Tesla at 4 Kelvin and the
graphene has a high quality due to its encapsulation in hexagonal boron
nitride. This allows us to study and exploit graphene Josephson junctions in a
new regime, characterized by ballistic transport. We find that the critical
current oscillates with the carrier density due to phase coherent interference
of the electrons and holes that carry the supercurrent caused by the formation
of a Fabry-P\'{e}rot cavity. Furthermore, relatively large supercurrents are
observed over unprecedented long distances of up to 1.5 m. Finally, in the
quantum Hall regime we observe broken symmetry states while the contacts remain
superconducting. These achievements open up new avenues to exploit the Dirac
nature of graphene in interaction with the superconducting state.Comment: Updated version after peer review. Includes supplementary material
and ancillary file with source code for tight binding simulation
Complete mitochondrial genomes and nuclear ribosomal RNA operons of two species of Diplostomum (Platyhelminthes: Trematoda): a molecular resource for taxonomy and molecular epidemiology of important fish pathogens
© 2015 Brabec et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License
(http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium,
provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://
creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article
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