188 research outputs found
The local dust foregrounds in the microwave sky: I. Thermal emission spectra
Analyses of the cosmic microwave background (CMB) radiation maps made by the
Wilkinson Microwave Anisotropy Probe (WMAP) have revealed anomalies not
predicted by the standard inflationary cosmology. In particular, the power of
the quadrupole moment of the CMB fluctuations is remarkably low, and the
quadrupole and octopole moments are aligned mutually and with the geometry of
the Solar system. It has been suggested in the literature that microwave sky
pollution by an unidentified dust cloud in the vicinity of the Solar system may
be the cause for these anomalies. In this paper, we simulate the thermal
emission by clouds of spherical homogeneous particles of several materials.
Spectral constraints from the WMAP multi-wavelength data and earlier infrared
observations on the hypothetical dust cloud are used to determine the dust
cloud's physical characteristics. In order for its emissivity to demonstrate a
flat, CMB-like wavelength dependence over the WMAP wavelengths (3 through 14
mm), and to be invisible in the infrared light, its particles must be
macroscopic. Silicate spheres from several millimetres in size and carbonaceous
particles an order of magnitude smaller will suffice. According to our
estimates of the abundance of such particles in the Zodiacal cloud and
trans-neptunian belt, yielding the optical depths of the order of 1E-7 for each
cloud, the Solar-system dust can well contribute 10 microKelvin (within an
order of magnitude) in the microwaves. This is not only intriguingly close to
the magnitude of the anomalies (about 30 microKelvin), but also alarmingly
above the presently believed magnitude of systematic biases of the WMAP results
(below 5 microKelvin) and, to an even greater degree, of the future missions
with higher sensitivities, e.g. PLANCK.Comment: 33 pages, 9 figures, 1 table. The Astrophysical Journal, 2009,
accepte
COMPARATIVE ANALYSIS OF THE FREQUENCY OF CYTOGENETIC ABNORMALIES IN THE ROOT APICAL MERISTEM OF SPRING BARLEY (<i>HORDEUM VULGARE </i> L.) CULTIVAE SEEDLINGS, CONTRASTING IN THEIR LEAD TOLERANCE
Cell division activity, frequencies and spectra of cytogenetical abnormalities were studied in the root apical meristem cells of spring barley seedlings (Hordeum vulgare L.). Comparative analysis of aberration frequencies in cells of most sensitive or tolerant barley cultivars was made. Sensitive and tolerant cultivars of spring barley were chosen by testing of lead influence on 100 barley cultivars from the VIR collection. Significant differences between groups of sensitive and tolerant cultivars were shown in indexes received on intact seedlings: frequencies of aberrant cells (FAC), frequency of cytogenetical abnormalities on a dividing cell (FADC), frequency of cytogenetical disturbances on a cell with cytogenetical abnormalities (FAAC). Mechanisms of tolerance to lead and HM were discussed
CAREER-GUIDANCE AND DIGITALIZATION AS LINKS OF ONE PROBLEM
The methods of work on professional information distribution, professional enlightenment, professional selection, professional education, professional social adaptation are revealed. Within the conditions of worldwide transition to digital economy the reevaluation of socio-economic situations occurs which has an eect on education sector, its relation to society, labour market, culture, a human being and, as a result, economic, moral, spiritual potential of society and civilization as a whole. The value system of the choice of the place of work and study by individuals, the motives for the choice of professional activity are specied
GRB Sky Distribution Puzzles
We analyze the randomness of the sky distribution of cosmic gamma-ray bursts.
These events are associated with massive galaxies, spiral or elliptical, and
therefore their positions should trace the large-scale structure, which, in
turn, could show up in the sky distribution of fluctuations of the cosmic
microwave background (CMB). We test this hypothesis by mosaic correlation
mapping of the distributions of CMB peaks and burst positions, find the
distribution of these two signals to be correlated, and interpret this
correlation as a possible systematic effect.Comment: 12 pages, 16 figures, 1 tabl
Can residuals of the Solar system foreground explain low multipole anomalies of the CMB ?
The low multipole anomalies of the Cosmic Microwave Background has received
much attention during the last few years. It is still not ascertained whether
these anomalies are indeed primordial or the result of systematics or
foregrounds. An example of a foreground, which could generate some non-Gaussian
and statistically anisotropic features at low multipole range, is the very
symmetric Kuiper Belt in the outer solar system. In this paper, expanding upon
the methods presented by Maris et al. (2011), we investigate the contributions
from the Kuiper Belt objects (KBO) to the WMAP ILC 7 map, whereby we can
minimize the contrast in power between even and odd multipoles in the CMB,
discussed discussed by Kim & Naselsky (2010). We submit our KBO de-correlated
CMB signal to several tests, to analyze its validity, and find that
incorporation of the KBO emission can decrease the quadrupole-octupole
alignment and parity asymmetry problems, provided that the KBO signals has a
non-cosmological dipole modulation, associated with the statistical anisotropy
of the ILC 7 map. Additionally, we show that the amplitude of the dipole
modulation, within a 2 sigma interval, is in agreement with the corresponding
amplitudes, discussed by Lew (2008).Comment: 24 pages, 9 figures, 5 tables. Matches version in JCA
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Status of Activities on Rehabilitation Of Radioactively Contaminated Facilities and the Site of Russian Research Center ''Kurchatov Institute''
This paper describes the program, the status, and the course of activities on rehabilitation of radioactively contaminated facilities and the territory of temporary radioactive waste (radwaste) disposal at the Russian Research Center ''Kurchatov Institute'' (RRC KI) in Moscow as performed in 2001-2002. The accumulation of significant amounts of radwaste at RRC KI territory is shown to be the inevitable result of Institute's activity performed in the days of former USSR nuclear weapons project and multiple initial nuclear power projects (performed from 1950's to early 1970's). A characterization of RRC KI temporary radwaste disposal site is given. Described is the system of radiation control and monitoring as implemented on this site. A potential hazard of adverse impacts on the environment and population of the nearby housing area is noted, which is due to possible spread of the radioactive plume by subsoil waters. A description of the concept and project of the RRC KI temporary radwaste disposal site is presented. Specific nature of the activities planned and performed stems from the nearness of housing area. This paper describes main stages of the planned activities for rehabilitation, their expected terms and sources of funding, as well as current status of the project advancement. Outlined are the problems faced in the performance and planning of works. The latter include: diagnostics of the concrete-grouted repositories, dust-suppression technologies, packaging of the fragmented ILW and HLW, soil clean-up, radioactive plume spread prevention, broad radiation monitoring of the work zone and environment in the performance of rehabilitation works. Noted is the intention of RRC KI to establish cooperation with foreign, first of all, the U.S. partners for the solution of problems mentioned above
Dominant Multipoles in WMAP5 Mosaic Data Correlation Maps
The method of correlation mapping on the full sphere is used to study the
properties of the ILC map, as well as the dust and synchrotron background
components. An anomalous correlation of the components with the ILC map in the
main plane and in the poles of the ecliptic and equatorial coordinate systems
was discovered. Apart from the bias, a dominant quadrupole contribution in the
power spectrum of the mosaic correlation maps was found in the pixel
correlation histogram. Various causes of the anomalous signal are discussed.Comment: 10 pages,11 figure
Advancing Tests of Relativistic Gravity via Laser Ranging to Phobos
Phobos Laser Ranging (PLR) is a concept for a space mission designed to
advance tests of relativistic gravity in the solar system. PLR's primary
objective is to measure the curvature of space around the Sun, represented by
the Eddington parameter , with an accuracy of two parts in ,
thereby improving today's best result by two orders of magnitude. Other mission
goals include measurements of the time-rate-of-change of the gravitational
constant, and of the gravitational inverse square law at 1.5 AU
distances--with up to two orders-of-magnitude improvement for each. The science
parameters will be estimated using laser ranging measurements of the distance
between an Earth station and an active laser transponder on Phobos capable of
reaching mm-level range resolution. A transponder on Phobos sending 0.25 mJ, 10
ps pulses at 1 kHz, and receiving asynchronous 1 kHz pulses from earth via a 12
cm aperture will permit links that even at maximum range will exceed a photon
per second. A total measurement precision of 50 ps demands a few hundred
photons to average to 1 mm (3.3 ps) range precision. Existing satellite laser
ranging (SLR) facilities--with appropriate augmentation--may be able to
participate in PLR. Since Phobos' orbital period is about 8 hours, each
observatory is guaranteed visibility of the Phobos instrument every Earth day.
Given the current technology readiness level, PLR could be started in 2011 for
launch in 2016 for 3 years of science operations. We discuss the PLR's science
objectives, instrument, and mission design. We also present the details of
science simulations performed to support the mission's primary objectives.Comment: 25 pages, 10 figures, 9 table
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