Abstract
We present the scientific program of the Spectr-M project aimed at the creation and operation of the Millimetron Space Observatory (MSO) planned for launch in the late 2020s. The unique ...technical capabilities of the observatory will enable broadband observations of astronomical objects from 50 μm to 10 mm wavelengths with a record sensitivity (up to ∼
0.1
μJy) in the single-dish mode and with an unprecedented high angular resolution (∼
0.1
μas) in the ground-space very long baseline interferometer (SVLBI) regime. The program addresses fundamental priority issues of astrophysics and physics in general that can be solved only with the MSO capabilities: 1) the study of physical processes in the early Universe up to redshifts
z
∼ 2 × 10
6
through measuring
μ
-distortions of the cosmic microwave background (CMB) spectrum, and investigation of the structure and evolution of the Universe at redshifts
z
< 15 by measuring
y
-distortions of the CMB spectrum; 2) the investigation of the geometry of space-time around supermassive black holes (SMBHs) in the center of our Galaxy and M87 by imaging surrounding shadows, the study of plasma properties in the shadow formation regions, and the search for observational manifestations of wormholes; 3) the study of observational manifestations of the origin of life in the Universe — the search for water and biomarkers in the Galactic interstellar medium. Moreover, the technical capabilities of the MSO can help solve related problems, including the birth of the first galaxies and SMBHs (
z
≳ 10), alternative approaches to measuring the Hubble constant, the physics of SMBHs in ‘dusty’ galactic nuclei, the study of protoplanetary disks and water transport in them, and the study of ‘ocean worlds’ in the Solar System.
This paper reviews a wide range of questions in astrophysics and cosmology that can be answered by astronomical observations in the far-IR to millimeter wavelength range and which include the ...formation and evolution of stars and planets, galaxies, and the interstellar medium, the study of black holes, and the development of the cosmological model. These questions are considered in relation to the Millimetron Space Observatory (Spectrum-M project), which is equipped with a aperture cooled telescope and can operate both as a single-dish telescope and as part of a space-ground very long baseline interferometer.
We apply the well-known semi-analytical model of formation of the Dark Matter (DM) haloes to discuss properties of the relaxed objects dominated by the DM component (such as the first and dwarf ...spheroidal galaxies (dSph) and/or clusters of galaxies). This approach allows us to obtain a simple but more detailed description of evolution of the first galaxies. It also reveals links between the observed characteristics of the relaxed DM haloes and the initial power spectrum of density perturbations. Results of our analysis of the observed properties of ∼40 DM dominated galaxies and ∼100 clusters of galaxies are consistent with the Λ cold dark matter like power spectrum of initial perturbations down to the scale of ∼10 kpc. For the DM dominated objects the scaling relations are also discussed.
This paper provides the results on spinel sampled from ailikites of the Bolshetagninskii massif of the East Sayan region. The study aimed to determine the history of formation of ultramafic ...lamprophyres of the Ziminsky complex. Spinel from three dikes of the Bolshetagninskii massif with different mineral compositions of the groundmass but similar textural and structural features (BTG 2/21, TGK 3, BTG 6/21) was analyzed. The content of the main elements and microcomponents in spinel was determined using electron microscope and microprobe. All spinel crystals are zonal, the following types have been identified with regard to the composition: chromites (Chr), aluminum-chromites (Al-Chr), chromium magnetites (Cr-Mgt), titanomagnetites (Ti-Mgt) and magnetites (Mgt). The composition of spinel from sample BTG 2/21 of ultramafic lamprophyres of the Bolshetagninskii massif shows the following trend: chromite→ aluminum-chromite→ chromium magnetite→ titanomagnetite→ magnetite. Sample TGK 3 contains spinel with compositional change from chromite→ chromium magnetite. Chromite cores from sample BTG 6/21 are overgrown with chromium magnetite, as well as titanomagnetite.
We assume the primary melt, from which the primary chromite crystallized, to be the same for all samples studied. After chromite formed from the same melt and possibly in the same chamber, each melt portion experiences its own history of formation as evidenced by spinel study.
The
forest observed in the spectra of quasars allows the evolution of the structure of the Universe and the properties of the ultraviolet (UV) background up to redshifts
6 to be studied. An analysis ...of the properties of
6000
forest lines observed at redshifts
shows that this forest can be formed by the absorption of radiation from quasars by strongly ionized hydrogen concentrated in dark matter (DM) halos and the intergalactic medium. We propose a physical model of absorbers that allows the observed characteristics of absorption lines to be associated with the properties of DM halos and the surrounding UV background. We show that the Doppler parameter and the gas temperature are determined by the injection energy being released during hydrogen photoionization and depend only on the spectrum of the surrounding UV background. In contrast, the observed number density of neutral hydrogen depends both on the intensity and spectrum of the UV background and on the mass and density of the DM halos. Our analysis can be used to distinguish the limited population of DM halos observed as
lines among the set of all DM halos.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Chuktukon alkaline carbonatite complex is a part of the Chadobets complex, situated in the southwestern part of the Siberian craton. It is composed principally of aillikite-damtjernite and ...carbonatite and a host of Nb and REE mineralisation. Zircons were collected from drillhole samples of the damtjernites and hydrothermally overprinted carbonatites. Zircon grains show oscillatory zoning and a significant signature of recrystallization in cathodoluminescence images. Oscillatory zoned zircons preserved primary signatures, whereas recrystallization processes were related to infiltration of carbonatite melt and late stage fluid. The recrystallization led to different changes in the zircon geochemistry and appearance of multiphase inclusions with mineral composition, which is common of carbonatites (alkali-rich carbonates, fluorcalciopyrochlore, fluorapatite, Ba-Sr-RЕЕ-Ca-carbonates, calcite, dolomite, phlogopite and others). Hf-isotope composition of oscillatory zoned and recrystallized zircons is similar and records the signature of their primary heterogeneous source, with ɛHf(t) varying from 6.3 to −0.6. U-Pb age of oscillatory zoned zircon from damtjernite shows that the rock was emplaced at 256.7 ± 1.1 Ma, indicating that the Chuktukon intrusion was coeval with the Permian-Triassic Siberian Traps (252–250 Ma) and extensive alkaline magmatism in the Siberian craton.
•The Chuktukon damtjernites yield U-Pb age of 256.7 ± 1.1 Ma.•The source region of the Chadobets complex was heterogeneous.•The mantle source was affected by carbonatite metasomatic component.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The prospects for observations of gravitationally lensed extragalactic sources in the far-infrared and submillimeter ranges of the electromagnetic spectrum by the planned space observatories with ...active cooling of the telescope mirror to cryogenic temperatures are considered. The possibility of solving topical cosmological and astrophysical problems related to the observations of gravitationally lensed sources is discussed. The number counts of lensed sources have been performed for various wavelengths in the range from 70 to 2000 µm. The redshift and magnification distributions of lensed sources and the mass distribution of lenses have been obtained. We have constructed model photometric sky maps for which the contribution from lensed sources has been calculated for the first time.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Borgoy and Botsy massifs are a part of the Dzhida alkaline province of the Western Transbaikalia. It has been stated that the rocks of the Borgoy massif were formed during the period from 246 to ...243 Ma, which coincides with the formation period of the Permian-Triassic alkaline magmatic rocks common in the Vitim province. The age obtained from the zircons in the Botsy massif (121±1.0 Ma) is typical of the final stage of the transformation of the rocks related to rifting and alkali basalt lava flow. The presence of negative Nb-Ta anomaly and a relative enrichment in Rb, Ba, Sr and U imply interaction between the material of the plume and the earlier accretionary complexes of the subduction zones.
We propose a method of analyzing the absorption spectra of quasars that allows the physical parameters of absorbing clouds, absorbers, to be roughly estimated: their masses, sizes, and mean ...densities. An analysis of three representative catalogs of the Lyman-alpha (
) forest and metal absorption line systems confirms that these observations refer to two types of objects with different properties, each of which forms a one-parameter sequence. The parameters of the metal absorption line systems are consistent with the corresponding estimates of the parameters of galaxies. The parameters of the
forest differ significantly from the galactic ones, but are close to the parameters of a large number of halos presented in numerical models. Possible reasons for the emergence of two one-parameter systems of halos with different properties are discussed.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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