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Atmospheric modelling for NOMAD-UVIS on board the ExoMars Trace Gas Orbiter mission
The Ultraviolet and Visible Spectrometer (UVIS) instrument development process requires the construction of an atmospheric model to provide synthetic UV transmission spectra. We discuss the requirements of the model to enable observational limits to be found, and the potential for certain atmospheric parameters to be further constrained
Peripheral visual response time to colored stimuli imaged on the horizontal meridian
Two male observers were administered a binocular visual response time task to small (45 min arc), flashed, photopic stimuli at four dominant wavelengths (632 nm red; 583 nm yellow; 526 nm green; 464 nm blue) imaged across the horizontal retinal meridian. The stimuli were imaged at 10 deg arc intervals from 80 deg left to 90 deg right of fixation. Testing followed either prior light adaptation or prior dark adaptation. Results indicated that mean response time (RT) varies with stimulus color. RT is faster to yellow than to blue and green and slowest to red. In general, mean RT was found to increase from fovea to periphery for all four colors, with the curve for red stimuli exhibiting the most rapid positive acceleration with increasing angular eccentricity from the fovea. The shape of the RT distribution across the retina was also found to depend upon the state of light or dark adaptation. The findings are related to previous RT research and are discussed in terms of optimizing the color and position of colored displays on instrument panels
Secondary teachers' perceptions of the effectiveness of their pre-service education and strategies to improve pre-service education for teachers: A school based training route in England
This study aims to provide a deeper understanding of the impact of an EBITT course on teachers' early professional development, identify strengths of the course and also the ways in which the training could be improved. Data collected was recorded during individual face- to- face interviews using a structured interview schedule. In devising our approach we utilised the model suggested by Sharon Feiman-Nemser in her article How do Teachers Learn to Teach? in Cochran - Smith et. al. (2008) Handbook of Research on Teacher Education
The data was analysed to explore (after 2-4 years reflection):
• which elements of initial training were valuable and less valuable
• what they have learned since the course
• which aspects of the course the teachers feel should be improved
It was cross referenced against findings from national surveys of teachers in their post qualifying year of teaching (induction year) and early years of teaching conducted by the TDA. These findings were presented as part of a common wider international study on the same theme in four countries (UK, Spain, Australia, and Ireland)
Reliability considerations in the design, assembly, and testing of the mariner iv power system
Reliability considerations in design, assembly, and testing of Mariner IV power syste
A simple encoding of a quantum circuit amplitude as a matrix permanent
A simple construction is presented which allows computing the transition
amplitude of a quantum circuit to be encoded as computing the permanent of a
matrix which is of size proportional to the number of quantum gates in the
circuit. This opens up some interesting classical monte-carlo algorithms for
approximating quantum circuits.Comment: 6 figure
Hysteresis of spectral evolution in the soft state of black-hole binary LMC X-3
We report the discovery of hysteresis between the x-ray spectrum and
luminosity of black-hole binary LMC X-3. Our observations, with the
Proportional Counter Array on the Rossi X-ray Timing Explorer, took place
entirely within the soft spectral state, dominated by a spectral component that
was fitted well with a multicolor disk blackbody. A power-law component was
seen only during times when the luminosity of the disk blackbody was declining.
The x-ray luminosity at these times was comparable to that seen in transient
systems (x-ray novae) when they return to the hard state at the end of an
outburst. Our observations may represent partial transitions to the hard state;
complete transitions have been seen in this system by Wilms et al. (2001). If
they are related to the soft-to-hard transition in transients, then they
demonstrate that hysteresis effects can appear without a full state transition.
We discuss these observations in the context of earlier observations of
hysteresis within the hard state of binaries 1E 1740.7-2942 and GRS 1758-258
and in relation to published explanations of hysteresis in transients.Comment: 14 pages, 6 figures, accepted by The Astrophysical Journa
Extending the applicability of an open-ring trap to perform experiments with a single laser-cooled ion
An open-ring ion trap, also referred to as transparent trap was initially
built up to perform - correlation experiments with radioactive
ions. This trap geometry is also well suited to perform experiments with
laser-cooled ions, serving for the development of a new type of Penning trap,
in the framework of the project TRAPSENSOR at the University of Granada. The
goal of this project is to use a single Ca ion as detector for
single-ion mass spectrometry. Within this project and without any modification
to the initial electrode configuration, it was possible to perform Doppler
cooling on Ca ions, starting from large clouds and reaching single
ion sensitivity. This new feature of the trap might be important also for other
experiments with ions produced at Radioactive Ion Beam (RIB) facilities. In
this publication, the trap and the laser system will be described, together
with their performance with respect to laser cooling applied to large ion
clouds down to a single ion.Comment: 9 pages, 13 figure
HI Absorption Toward HII Regions at Small Galactic Longitudes
We make a comprehensive study of HI absorption toward HII regions located
within Galactic longitudes less than 10 degrees. Structures in the extreme
inner Galaxy are traced using the longitude-velocity space distribution of this
absorption. We find significant HI absorption associated with the Near and Far
3kpc Arms, the Connecting Arm, Banias Clump 1 and the H I Tilted Disk. We also
constrain the line of sight distances to HII regions, by using HI absorption
spectra together with the HII region velocities measured by radio recombination
lines.Comment: Complete figure set available in online version of journal. Accepted
by ApJ August 8, 201
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