1,073 research outputs found
TESTING AND PERSPECTIVES OF THE METHODS FOR INVESTIGATION OF FLUCTUATING ASYMMETRY OF FISH SPECIES IN BAIKAL REGION
The study shown that the proportion of asymmetric fish in the Baikal Lake was smaller than in the Bratsk Reservoir. In both samples asymmetric specimens only by one of the examined characteristics were dominated. The remaining fish had simultaneously two or three signs that were deviated from symmetry. Asymmetrical individuals by four signs were not detected
Diffraction based Hanbury Brown and Twiss interferometry performed at a hard x-ray free-electron laser
We demonstrate experimentally Hanbury Brown and Twiss (HBT) interferometry at
a hard X-ray Free Electron Laser (XFEL) on a sample diffraction patterns. This
is different from the traditional approach when HBT interferometry requires
direct beam measurements in absence of the sample. HBT analysis was carried out
on the Bragg peaks from the colloidal crystals measured at Linac Coherent Light
Source (LCLS). We observed high degree (80%) spatial coherence of the full beam
and the pulse duration of the monochromatized beam on the order of 11 fs that
is significantly shorter than expected from the electron bunch measurements.Comment: 32 pages, 10 figures, 2 table
Charm production nearby threshold in pA-interactions at 70 GeV
The results of the SERP-E-184 experiment at the U-70 accelerator (IHEP,
Protvino) are presented. Interactions of the 70 GeV proton beam with C, Si and
Pb targets were studied to detect decays of charmed , ,
, mesons and baryon near their production threshold.
Measurements of lifetimes and masses are shown a good agreement with PDG data.
The inclusive cross sections of charm production and their A-dependencies were
obtained. The yields of these particles are compared with the theoretical
predictions and the data of other experiments. The measured cross section of
the total open charm production ( = 7.1
2.3(stat) 1.4(syst) b/nucleon) at the collision c.m. energy
= 11.8 GeV is well above the QCD model predictions. The
contributions of different species of charmed particles to the total cross
section of the open charm production in proton-nucleus interactions vary with
energy.Comment: 4 pages, 6 pages, 38th International Conference on High Energy
Physics 3-10 August 2016, Chicago, US
Hadron calorimeter with MAPD readout in the NA61/SHINE experiment
The modular hadron calorimeter with micro-pixel avalanche photodiodes readout
for the NA61/SHINE experiment at the CERN SPS is presented. The calorimeter
consists of 44 independent modules with lead-scintillator sandwich structure.
The light from the scintillator tiles is captured by and transported with
WLS-fibers embedded in scintillator grooves. The construction provides a
longitudinal segmentation of the module in 10 sections with independent MAPD
readout. MAPDs with pixel density of /mm ensure good linearity of
calorimeter response in a wide dynamical range. The performance of the
calorimeter prototype in a beam test is reported
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