6,320 research outputs found
GBM Observations of V404 Cyg During its 2015 Outburst
V404 Cygni was discovered in 1989 by the X-ray satellite during its
only previously observed X-ray outburst and soon after confirmed as a black
hole binary. On June 15, 2015, the Gamma Ray Burst Monitor (GBM) triggered on a
new outburst of V404 Cygni. We present 13 days of GBM observations of this
outburst including Earth occultation flux measurements, spectral and temporal
analysis. The Earth occultation fluxes reached 30 Crab with detected emission
to 100 keV and determined, via hardness ratios, that the source was in a hard
state. At high luminosity, spectral analysis between 8 and 300 keV showed that
the electron temperature decreased with increasing luminosity. This is expected
if the protons and electrons are in thermal equilibrium during an outburst with
the electrons cooled by the Compton scattering of softer seed photons from the
disk. However, the implied seed photon temperatures are unusually high,
suggesting a contribution from another source, such as the jet. No evidence of
state transitions is seen during this time period. The temporal analysis
reveals power spectra that can be modeled with two or three strong, broad
Lorentzians, similar to the power spectra of black hole binaries in their hard
state
Vegetation and environmental responses to climate forcing during the last glacial maximum and deglaciation in the East Carpathians: attenuated response to maximum cooling and increased biomass burning
Disordered proteins and network disorder in network descriptions of protein structure, dynamics and function. Hypotheses and a comprehensive review
During the last decade, network approaches became a powerful tool to describe protein structure and dynamics. Here we review the links between disordered proteins and the associated networks, and describe the consequences of local, mesoscopic and global network disorder on changes in protein structure and dynamics. We introduce a new classification of protein networks into ‘cumulus-type’, i.e., those similar to puffy (white) clouds, and ‘stratus-type’, i.e., those similar to flat, dense (dark) low-lying clouds, and relate these network types to protein disorder dynamics and to differences in energy transmission processes. In the first class, there is limited overlap between the modules, which implies higher rigidity of the individual units; there the conformational changes can be described by an ‘energy transfer’ mechanism. In the second class, the topology presents a compact structure with significant overlap between the modules; there the conformational changes can be described by ‘multi-trajectories’; that is, multiple highly populated pathways. We further propose that disordered protein regions evolved to help other protein segments reach ‘rarely visited’ but functionally-related states. We also show the role of disorder in ‘spatial games’ of amino acids; highlight the effects of intrinsically disordered proteins (IDPs) on cellular networks and list some possible studies linking protein disorder and protein structure networks
Integrated pest management of major pests and diseases in eastern Europe and the Caucasus
This book promotes Integrated Pest Management, to contribute to reduced reliance on pesticides and the avoidance of adverse impacts from pesticide use on the health and safety of farming communities, consumers and the environment. Through the IPM approach, technical advice is provided to help plan methods and measures to control major pests and diseases occurring or expected to occur in the countries of Western Asia and Eastern Europe. The specific descriptions contain a short summary of the biology of the species, completed with information on methods and tools of monitoring and control. Preventive control methods are also discussed
Analysis of Sub-threshold Short Gamma-ray Bursts in Fermi GBM Data
The Fermi Gamma-ray Burst Monitor (GBM) is currently the most prolific
detector of Gamma-Ray Bursts (GRBs). Recently the detection rate of short GRBs
(SGRBs) has been dramatically increased through the use of ground-based
searches that analyze GBM continuous time tagged event (CTTE) data. Here we
examine the efficiency of a method developed to search CTTE data for
sub-threshold transient events in temporal coincidence with LIGO/Virgo compact
binary coalescence triggers. This targeted search operates by coherently
combining data from all 14 GBM detectors by taking into account the complex
spatial and energy dependent response of each detector. We use the method to
examine a sample of SGRBs that were independently detected by the Burst Alert
Telescope on board the Neil Gehrels Swift Observatory, but which were too
intrinsically weak or viewed with unfavorable instrument geometry to initiate
an on-board trigger of GBM. We find that the search can successfully recover a
majority of the BAT detected sample in the CTTE data. We show that the targeted
search of CTTE data will be crucial in increasing the GBM sensitivity, and
hence the gamma-ray horizon, to weak events such as GRB 170817A. We also
examine the properties of the GBM signal possibly associated with the LIGO
detection of GW150914 and show that it is consistent with the observed
properties of other sub-threshold SGRBs in our sample. We find that the
targeted search is capable of recovering true astrophysical signals as weak as
the signal associated with GW150914 in the untriggered data.Comment: 10 pages, 9 figures, 1 table, submitted to Ap
Nano-sized phase inclusions in As₂S₃ glass, films and fibers based on this glass
In this report, the comparative analysis using Raman spectroscopy of the short-range order in amorphous As₂S₃ films deposited with different evaporation rates, volume glass and fiber based on this glass is presented. With increasing the film deposition rate, their structure becomes more non-uniform as compared to that of glass. Raman spectra excited by laser radiation with energy bigger than the width of the optical gap indicate photomodification of the structure of As₂S₃ glass and fiber based on it
Energy dependence of kaon-to-proton ratio fluctuations in central Pb+Pb collisions from = 6.3 to 17.3 GeV
Kaons and protons carry large parts of two conserved quantities, strangeness
and baryon number. It is argued that their correlation and thus also
fluctuations are sensitive to conditions prevailing at the anticipated
parton-hadron phase boundary. Fluctuations of the and
ratios have been measured for the first time by NA49 in central Pb+Pb
collisions at 5 SPS energies between = 6.3 GeV and 17.3 GeV.
Both ratios exhibit a change of sign in , a measure of
non-statistical fluctuations, around = 8 GeV. Below this
energy, is positive, indicating higher fluctuation
compared to a mixed event background sample, while for higher energies,
is negative, indicating correlated emission of kaons
and protons. The results are compared to UrQMD calculations which which give a
good description at the higher SPS energies, but fail to reproduce the
transition to positive values.Comment: 5 pages, 4 figure
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