ASTRONIRCAM is an infrared camera-spectrograph installed at the 2.5-meter telescope of the CMO SAI. The instrument is equipped with the HAWAII-2RG array. A bad pixels classification of the ASTRONIRCAM detector is proposed. The classification is based
on histograms of the difference of consecutive non-destructive readouts of a flat field. Bad pixels are classified into 5 groups: hot (saturated on the first readout), warm (the signal accumulation rate is above the mean value by more than 5 standard deviations), cold (the rate is under the mean value by more than 5 standard deviations), dead (no signal accumulation), and inverse (having a negative signal accumulation in the first readouts). Normal pixels of the ASTRONIRCAM detector account for 99.6% of the total. We investigated the dependence between the amount of bad pixels and the number of cooldown cycles of the instrument. While hot pixels remain the same, the bad pixels of other types may migrate between groups. The number of pixels in each group stays roughly constant. We found that the mean and variance of the bad pixels amount in each group and the transitions between groups do not differ noticeably between normal or slow cooldowns.
It is known that hyperedge replacement grammars are similar to string context-free grammars in the sense of definitions and properties. Therefore, we expect that there is a generalization of the well-known Greibach normal form from string grammars to
hypergraph grammars. Such generalized normal forms are presented in several papers; however, they do not cover a large class of hypergraph languages (e.g. languages consisting of star graphs). In this paper, we introduce a weak Greibach normal form, whose definition corresponds to the lexicalized normal form for string grammars, and prove that every context-free hypergraph language (with nonsubstantial exceptions) can be generated by a grammar in this normal form. The proof presented in this paper generalizes a corresponding one for string grammars with a few more technicalities.
The study deals with the ruin problem when an insurance company having two business branches, life insurance and non-life insurance, invests its reserve into a risky asset with the price dynamics given by a geometric Brownian motion. We prove a resul
t on smoothness of the ruin probability as a function of the initial capital and obtain for it an integro-differential equation understood in the classical sense. For the case of exponentially distributed jumps we show that the survival probability is a solution of an ordinary differential equation of the 4th order. Asymptotic analysis of the latter leads to the conclusion that the ruin probability decays to zero in the same way as in the already studied cases of models with one-side jumps.
This is a historical review covering the last 30 years of the observational study of lenticular galaxies at the 6m telescope BTA of the Special Astrophysical Observatory of the Russian Academy of Sciences. The development of spectroscopic techniques
at the BTA has allowed to get comprehensive information about this class of stellar systems, starting from the study of their nuclei in the late 80th towards quite exclusive results obtained in the last years on the outermost parts of their large-scale stellar disks.
Algebras generated by strictly positive matrices are described up to similarity, including the commutative, simple, and semisimple cases. We provide sufficient conditions for some block diagonal matrix algebras to be generated by a set of nonnegative
matrices up to similarity. Also we find all realizable dimensions of algebras generated by two nonnegative semi-commuting matrices. The last result provides the solution to the problem posed by M. Kandi{c}, K. v{S}ivic (2017).
The possibility of identification of an observable CMS $mu^+ mu^-$ excess at 28 GeV in the channel $ppto mu^+ mu^- b bar b$ at $sqrt{s}$=8 TeV and 13 TeV as a manifestation of one of the minimal supersymmetric standard model (MSSM) Higgs bosons is in
vestigated. The MSSM parametric scenarios in the regime of large threshold corrections involving low-mass CP-odd scalar, a 125 GeV CP-even scalar and other Higgs bosons with suitable masses are found, where the alignment limit conditions for the Higgs couplings are respected. Perturbative unitarity bounds and constraints on the electroweak vacuum stability are discussed in the regime of substantial couplings with the top- and bottom superpartners. LHC phenomenology including top-quark decay in such a regime is analyzed.
Cassiopeia A, one of the most intriguing galactic supernova remnants, has been a target of many observational efforts including most recent observations by ALMA, Hubble, Herschel, Spitzer, NuSTAR, Integral, and other observatories. We use recent gamm
a-ray lines observations of the radioactive products of Cas A supernova explosive nucleosynthesis as well as spectral energy densities derived for Cas A at infrared wavelengths to speculate about the possibility of radioactive 44Ti being locked into large dust grains. This suggestion is also supported by the possible observation of a pre-supernova outburst about 80 years before the actual Cas A supernova explosion in 1671 AD by Italian astronomer G.D. Cassini. The plausibility of such a scenario is discussed also with reference to recent supernovae, and to the contribution of core-collapse supernovae to the overall dust production in the Galaxy.
We formulate and prove an analog of the classical Morse-Darboux lemma for the case of a surface with boundary.
We discussed quantum deformations of D=4 Lorentz and Poincare algebras. In the case of Poincare algebra it is shown that almost all classical r-matrices of S. Zakrzewski classification correspond to twisted deformations of Abelian and Jordanian types
. A part of twists corresponding to the r-matrices of Zakrzewski classification are given in explicit form.
Strongly noncircular outer stellar disks have been found in two unbarred SA0 galaxies by analyzing spectroscopic data on the rotation of stars and photometric data on the shape and orientation of the isophotes. In NGC 502, the oval distortion of the
disk is manifested as two elliptical rings, the inner and the outer ones, covering wide radial zones between the bulge and the disk and at the outer edge of the stellar disk. Such a structure may be a consequence of the so-called dry minor merger - multiple accretion of gas-free satellites. In NGC 5485, the kinematical major axis does not coincide with the orientation of isophotes in the disk-dominated region, and for this galaxy the conclusion about its global triaxial structure is unavoidable.
