The scheme and components of a wide field-of-view meter-wavelength radio telescope prototype developed based on an antenna array consisting of 128 dipoles is described. The operating frequency range ...is 38–74 MHz. Main parameters of the future prototype are presented and versions of its development are discussed.
The article presents the latest data on the prevalence of diabetes mellitus, the features of micronutrient status of these patients, the consequences of vitamin and mineral deficiency and its ...correction.
We consider vector extremal problems in the theory of logarithmic potential with external field by looking at an example of two-dimensional problems with Nikishin interaction matrix and variable ...masses and of the first and second components of the vector measure, respectively. The dependence of the supports of the equilibrium measures, equlibrium constants and energy on the parameter is analysed. Integral formulae recovering the extremal measure with mass from the supports of extremal measures with smaller masses are obtained. Bibliography: 27 titles.
Neutral pion photoproduction has been measured from 550 to 1500 MeV with the GRAAL facility, located at the ESRF in Grenoble. Differential cross-section and beam asymmetry have been measured over a ...wide angular range. These high-precision data improve significantly the database for the beam asymmetry in the second and third resonance regions covering for the first time the energy domain 1100-1500 MeV. New partial-wave analyses including these data are presented for which the beam asymmetry brings crucial constraints.
Photonuclear methods used earlier in experiments at electron accelerators have been adapted for femtosecond pulsed lasers. In particular, the problem of measuring wide electron spectra under ...conditions of a high counting rate and, hence, a high probability of pulse pileup has been solved. To provide long-term stability of electron beams from plasma, a magnetic spectrometer combined with a magnetic-induction sensor has been developed. This spectrometer is capable of measuring the electron-beam characteristics in each ultrashort laser pulse. The results of the experiments carried out with the femtosecond laser system at the International Laser Center of the Moscow State University are presented.
An algorithm is proposed that provides reliable discrimination between neutrons and γ rays in mixed fields and reduces the influence of γ-ray pileups at a slight complication of the hardware and the ...algorithms. The algorithm uses a stepwise Gatti filter for two detection periods (a short period of several hundreds of nanoseconds and a long period of a few microseconds) for the same event. Using mathematical simulation of 12000 neutron and γ-ray events, it has been demonstrated that at particle energies of ~128 keV in the electron equivalent (
ee
), the algorithm suppresses γ-ray pileups on a level of 10
4
with a neutron loss of only approximately 1%. Due to the proposed algorithm, the counting ability is of the order of 10
5
events/s.
The double pi(0) photoproduction off the proton has been measured in the beam energy range of 0.65-1.5 GeV. The total and differential cross sections and the Sigma beam asymmetry were extracted. The ...total cross section measured for the first time in the third resonance region of the nucleon shows a prominent peak. The interpretation of these results by two independent theoretical models infers mostly the selective excitation of P11- and D13-nucleon resonances.
We consider extremal problems for the energy of the logarithmic potential with external fields closely related with the inverse spectral problem method. The method is based on the relations between ...the external field and the supports of the equilibrium measures which were discovered in the pioneering papers of Rakhmanov, Saff, Mhaskar and Buyarov (
RSMB-method
). We propose a generalization of the RSMB-method for the vector of measures with matrix of interaction between components.
The classical universality theorem states that the Christoffel–Darboux kernel of the Hermite polynomials scaled by a factor of
1
/
n
tends to the sine kernel in local variables
x
˜
,
y
˜
in a ...neighborhood of a point
x
∗
∈
(
−
2
,
2
)
). This classical result is well known for
x
~
,
y
~
∈
K
⋐
R
. In this paper, we show that this classical result remains valid for expanding compact sets
K
=
K
(
n
). An interesting phenomenon of admissible dependence of the expansion rate of compact sets
K
(
n
) on
x
* is established. For
x
∗
∈
(
−
2
,
2
)
∖
{
0
}
) and for
x
* = 0, there are different growth regimes of compact sets
K
(
n
). A transient regime is found.
The BGO Calorimeter of BGO-OD Experiment Bantes, B; Bayadilov, D; Beck, R ...
Journal of physics. Conference series,
01/2015, Letnik:
587, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The BGO Rugby Ball is a large solid angle electromagnetic calorimeter now installed in the ELSA Facility in Bonn. The BGO is operating in the BGO-OD experiment aiming to study meson photoproduction ...off proton and neutron induced by a Bremsstrahlung polarized gamma beam of energies from 0.2 to 3.2 GeV and an intensity of 5 × 107 photons per second. The scintillating material characteristics and the photomultiplier read-out make this detector particularly suited for the detection of medium energy photons and electrons with very good energy resolution. The detector has been equipped with a new electronics read-out system, consisting of 30 sampling ADC Wie-Ne-R modules which perform the off-line reconstruction of the signal start-time allowing for a good timing resolution. Performances in linearity, resolution and time response have been carefully tested at the Beam Test Facility of the INFN National Laboratories in Frascati by using a matrix of 7 BGO crystals coupled to photomultipliers and equipped with the Wie-Ne-R sampling ADCs.
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