166 research outputs found
An electric quadrupole transition in the A1pi - X1sigma system of CO
Electric quadrupole transition in carbon monoxid
High-Resolution Measurements of Intersystem Bands of Carbon Monoxide toward X Persei
In an echelle spectrum of X Per acquired with the Space Telescope Imaging
Spectrograph we have identified individual rotational lines of 11
triplet-singlet (intersystem) absorption bands of ^12CO. Four bands provide
first detections for interstellar clouds. From a comparison with the zeta Oph
sight line we find that X Per is obscured by a higher 12CO column density of
1.4 x 10^16 cm-2. Together with the high spectral resolution of 1.3 km s-1,
this allows (i) an improved measurement of previously published f-values for
seven bands, and (ii) an extraction of the first astrophysical oscillator
strengths for d-X (8-0), (9-0), and (10-0), as well as for e-X (12-0). The
^13CO d-X (12-0) band, previously suspected to exist toward zeta Oph, is now
readily resolved and modeled. Our derived intersystem f-values for ^12CO
include a few mild (leq 34%) disagreements with recent predictions from a
perturbation analysis calculated for the interstellar excitation temperature.
Overall, the comparison confirms the superiority of employing multiple singlet
levels in the calculations of mixing coefficients over previous single-level
predictions.Comment: 11 pages (incl. 1 figure). Accepted by ApJ Letter
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Modelling methodologies for quality assessment of 3D inkjet printed electronic products
Purpose of the Fraunhofer Direct Digital Manufacturing Conference is an intellectual exchange between researchers, enterprises and users of Additive Manufacturing technologies in order to gather the latest information about trends, progress, importance and the future potential of these technologies for industrial applications. The range of topics covers Product Development (incl. simulation, co-design, mass customization), Technologies (incl. bio-printing, hybrid processes, novel developments/visionary concepts, process chains for industrial production), Materials (incl. ceramics, bio-materials, multi-material approaches), Quality (incl. process/ part quality management) as well as further innovative and visionary approaches not fitting the range of topics above. Renowned international keynote speakers give insight into the latest trends and challenges in additive manufacturing in a variety of industry sectors, including biomedical, aerospace and automotive
Correlation of a solar flare with a visual aurora
Correlation of solar flare with visual auror
Oscillator Strengths for B-X, C-X, and E-X Transitions in Carbon Monoxide
Band oscillator strengths for electronic transitions in CO were obtained at
the Synchrotron Radiation Center of the University of Wisconsin-Madison. Our
focus was on transitions that are observed in interstellar spectra with the Far
Ultraviolet Spectroscopic Explorer; these transitions are also important in
studies of selective isotope photodissociation where fractionation among
isotopomers can occur. Absorption from the ground state (X ^1Sigma^+ v'' = 0)
to A ^1Pi (v'= 5), B ^1Sigma^+ (v' = 0, 1), C ^1Sigma^+ (v' = 0, 1), and E ^1Pi
(v' = 0) was measured. Fits to the A - X (5, 0) band, whose oscillator strength
is well known, yielded the necessary column density and excitation temperature.
These parameters were used in a least-squares fit of the observed profiles for
the transitions of interest to extract their band oscillator strengths. Our
oscillator strengths are in excellent agreement with results from recent
experiments using a variety of techniques. This agreement provides the basis
for a self-consistent set of f-values at far ultraviolet wavelengths for
studies of interstellar (and stellar) CO.Comment: 22 pages, 3 figures, ApJS (in press
Accurate measurement of thermal expansion of solids between 77 K and 350 K by 3-terminal capacitance method
Outcome of paediatric intensive care survivors
The development of paediatric intensive care has contributed to the improved survival of critically ill children. Physical and psychological sequelae and consequences for quality of life (QoL) in survivors might be significant, as has been determined in adult intensive care unit (ICU) survivors. Awareness of sequelae due to the original illness and its treatment may result in changes in treatment and support during and after the acute phase. To determine the current knowledge on physical and psychological sequelae and the quality of life in survivors of paediatric intensive care, we undertook a computerised comprehensive search of online databases for studies reporting sequelae in survivors of paediatric intensive care. Studies reporting sequelae in paediatric survivors of cardiothoracic surgery and trauma were excluded, as were studies reporting only mortality. All other studies reporting aspects of physical and psychological sequelae were analysed. Twenty-seven studies consisting of 3,444 survivors met the selection criteria. Distinct physical and psychological sequelae in patients have been determined and seemed to interfere with quality of life. Psychological sequelae in parents seem to be common. Small numbers, methodological limitations and quantitative and qualitative heterogeneity hamper the interpretation of data. We conclude that paediatric intensive care survivors and their parents have physical and psychological sequelae affecting quality of life. Further well-designed prospective studies evaluating sequelae of the original illness and its treatment are warranted
Making the headlines: EU Immigration to the UK and the wave of new racism after Brexit
This chapter explores the immigration-related topics in the news media during the EU referendum campaign in the UK (April–June 2016) and after (July–September 2016). The chapter argues that attitudes anti-EU immigration are a wave of “new(s)” racism (van Dijk 2000) in the UK and EU immigration is frequently used as an umbrella term for Eastern European immigration being often mixed with non-EU immigration and the refugee crisis. The data shows that the prevalence of negative news stories has led to a distinctive immigration-narrative, confirming the claim of Hoffner and Cohen (2013) that members of minority groups are almost always associated with violent and threatening media content
Current assessment of the Red Rectangle band problem
In this paper we discuss our insights into several key problems in the
identification of the Red Rectangle Bands (RRBs). We have combined three
independent sets of observations in order to try to define the constraints
guiding the bands. We provide a summary of the general behavior of the bands
and review the evidence for a molecular origin of the bands. The extent,
composition, and possible absorption effects of the bands are discussed.
Comparison spectra of the strongest band obtained at three different spectral
resolutions suggests that an intrinsic line width of individual rotational
lines can be deduced. Spectroscopic models of several relatively simple
molecules were examined in order to investigate where the current data are
weak. Suggestions are made for future studies to enhance our understanding of
these enigmatic bands
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