1,365 research outputs found
К палеоантропологии средневекового населения Поволжья
Physical appearance of the population of the Golden Horde resulted from interbreeding of representatives of two big races, i.e. the Mongoloid and the Caucasoid. The presence of the Mongoloid component is to some extent manifested in the appearance of inhabitants of all the Golden Horde towns. Nevertheless, it is the Caucasoid features that prevailed in urban population
Effects of international climate policy for India: Evidence from a national and global CGE model
In order to reach the two degree target it is necessary to control CO2 emissions also in fast growing emerging economies such as India. The question is how the Indian economy would be affected by e.g. including the country into an international climate regime. Existing analyses with either a global model or a single country computable general equilibrium model miss important aspects such as distributional issues or international repercussions. By soft-linking models of these two classes, we provide a more detailed view on these issues. In particular, we analyze different options of transferring revenues from domestic carbon taxes and international transfers to different household types and how different assumptions on exchange rates affect transfer payments. We also show effects stemming from international price repercussions. Our analysis focusses on how these transmission channels affect welfare of nine different household types
Waveform control of orientation-dependent ionization of DCl in few-cycle laser fields
Strong few-cycle light fields with stable electric field waveforms allow controlling electrons on time scales down to the attosecond domain. We have studied the dissociative ionization of randomly oriented DCl in 5 fs light fields at 720 nm in the tunneling regime. Momentum distributions of D+ and Cl+ fragments were recorded via velocity-map imaging. A waveformdependent anti-correlated directional emission of D+ and Cl+ fragments is observed. Comparison of our results with calculations indicates that tailoring of the light field via the carrier envelope phase permits the control over the orientation of DCl+ and in turn the directional emission of charged fragments upon the breakup of the molecular ion
An integrated proxy and simulation data initiative for the Holocene and the last deglaciation
Novel Nonreciprocal Acoustic Effects in Antiferromagnets
The possible occurrence of nonreciprocal acoustic effects in antiferromagnets
in the absence of an external magnetic field is investigated using both (i) a
microscopic formulation of the magnetoelastic interaction between spins and
phonons and (ii) symmetry arguments. We predict for certain antiferromagnets
the existence of two new nonreciprocal (non-time invariant) effects:
A boundary-condition induced nonreciprocal effect and the occurrence of
transversal phonon modes propagating in opposite directions having different
velocities. Estimates are given and possible materials for these effects to be
observed are suggested.Comment: Euro. Phys. Lett. (in press
Clinical aspects of antenatal glucocorticoid treatment for prevention of neonatal respiratory distress syndrome
Peer Reviewe
FACT - Threshold prediction for higher duty cycle and improved scheduling
The First G-APD Cherenkov telescope (FACT) is the first telescope using
silicon photon detectors (G-APD aka. SiPM). The use of Silicon devices promise
a higher photon detection efficiency, more robustness and higher precision than
photo-multiplier tubes. Being operated during different light-conditions, the
threshold settings of a Cherenkov telescope have to be adapted to feature the
lowest possible threshold but also an efficient suppression of triggers from
night-sky background photons. Usually this threshold is set either by
experience or a mini-ratescan. Since the measured current through the sensors
is directly correlated with the noise level, the current can be used to set the
best threshold at any time. Due to the correlation between the physical
threshold and the final energy threshold, the current can also be used as a
measure for the energy threshold of any observation. This presentation
introduces a method which uses the properties of the moon and the source
position to predict the currents and the corresponding energy threshold for
every upcoming observation allowing to adapt the observation schedule
accordingly
FACT - How stable are the silicon photon detectors?
The First G-APD Cherenkov telescope (FACT) is the first telescope using
silicon photon detectors (G-APD aka. SiPM). The use of Silicon devices promise
a higher photon detection efficiency, more robustness and higher precision than
photo-multiplier tubes. Since the properties of G-APDs depend on auxiliary
parameters like temperature, a feedback system adapting the applied voltage
accordingly is mandatory.
In this presentation, the feedback system, developed and in operation for
FACT, is presented. Using the extraction of a single photon-equivalent (pe)
spectrum as a reference, it can be proven that the sensors can be operated with
very high precision. The extraction of the single-pe, its spectrum up to
10\,pe, its properties and their precision, as well as their long-term behavior
during operation are discussed. As a by product a single pulse template is
obtained. It is shown that with the presented method, an additional external
calibration device can be omitted. The presented method is essential for the
application of G-APDs in future projects in Cherenkov astronomy and is supposed
to result in a more stable and precise operation than possible with
photo-multiplier tubes
FACT - Long-term stability and observations during strong Moon light
The First G-APD Cherenkov Telescope (FACT) is the first Cherenkov telescope
equipped with a camera made of silicon photon detectors (G-APD aka. SiPM).
Since October 2011, it is regularly taking data on the Canary Island of La
Palma. G-APDs are ideal detectors for Cherenkov telescopes as they are robust
and stable. Furthermore, the insensitivity of G-APDs towards strong ambient
light allows to conduct observations during bright Moon and twilight. This gain
in observation time is essential for the long-term monitoring of bright TeV
blazars. During the commissioning phase, hundreds of hours of data (including
data from the the Crab Nebula) were taken in order to understand the
performance and sensitivity of the instrument. The data cover a wide range of
observation conditions including different weather conditions, different zenith
angles and different light conditions (ranging from dark night to direct full
Moon). We use a new parmetrisation of the Moon light background to enhance our
scheduling and to monitor the atmosphere. With the data from 1.5 years, the
long-term stability and the performance of the camera during Moon light is
studied and compared to that achieved with photomultiplier tubes so far.Comment: 3 pages, 3 figures, FACT Contribution to the 33rd International
Cosmic Ray Conference (ICRC), Rio de Janeir
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