70 research outputs found
Calculation of The Band Gap Energy and Study of Cross Luminescence in Alkaline-Earth Dihalide Crystals
The band gap energy as well as the possibility of cross luminescence
processes in alkaline-earth dihalide crystals have been calculated using the ab
initio Perturbed-Ion (PI) model. The gap is calculated in several ways: as a
difference between one-electron energy eigenvalues and as a difference between
total energies of appropriate electronic states of the crystal, both at the HF
level and with inclusion of Coulomb correlation effects. In order to study the
possibility of ocurrence of cross luminescence in these materials, the energy
difference between the valence band and the upmost core band for some
representative crystals has been calculated. Both calculated band gap energies
and cross luminescence predictions compare very well with the available
experimental results.Comment: LaTeX file containing 8 pages plus 1 postscript figure. Final version
accepted for publication in The Journal of the Physical Society of Japan. It
contains a more complete list of references, as well as a more detailed
comparison with previous theoretical investigations on the subjec
Interactions between the atmosphere, cryosphere, and ecosystems at northern high latitudes
The Nordic Centre of Excellence CRAICC (Cryosphere–Atmosphere Interactions
in a Changing Arctic Climate), funded by NordForsk in the years 2011–2016,
is the largest joint Nordic research and innovation initiative to date,
aiming to strengthen research and innovation regarding climate change issues
in the Nordic region. CRAICC gathered more than 100 scientists from all
Nordic countries in a virtual centre with the objectives of identifying and
quantifying the major processes controlling Arctic warming and related feedback
mechanisms, outlining strategies to mitigate Arctic warming, and developing
Nordic Earth system modelling with a focus on short-lived climate
forcers (SLCFs), including natural and anthropogenic aerosols.
The outcome of CRAICC is reflected in more than 150 peer-reviewed scientific
publications, most of which are in the CRAICC special issue of the journal
Atmospheric Chemistry and Physics. This paper presents an overview
of the main scientific topics investigated in the centre and provides the
reader with a state-of-the-art comprehensive summary of what has been achieved in
CRAICC with links to the particular publications for further detail. Faced
with a vast amount of scientific discovery, we do not claim to completely
summarize the results from CRAICC within this paper, but rather
concentrate here on the main results which are related to feedback loops in
climate change–cryosphere interactions that affect Arctic amplification.</p
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