V 361 Lyrae: An exotic binary system with a “Hot Spot” between the components?

A phenomenological model for V 361 Lyr is proposed. Probably it is a binary system which consists of a mass accreting primary star with mass of about M₁ ≈ 0·81 M⊙ and radius R₁ ≈ (6.1 ± 0·4) · 10¹⁰ cm and a mass losing secondary with about M₂ ≈ 0·77 M⊙ and R₂ ≈ 5.8 · 10¹⁰ cm. The secondary fills its Roche lobe, but the primary is something smaller than this lobe, contrary to the models of W UMa-type systems. So the hot spot appears in the atmosphere of the primary, but not in a disk, like in cataclysmic variables. The luminosity of the hot spot, L = (6-15) · 10³² erg/s, is large enough to be the main emission source of the system in visible light. So phenomenologically the object may be somewhat between W UMa-type stars and cataclysmic variables.     

The short‐period low‐mass binary system CC Com revisited

In this study we determined precise orbital and physical parameters of the very short‐period low‐mass contact binary system CC Com. The parameters are obtained by analysis of new CCD data combined with archival spectroscopic data. The physical parameters of the cool and hot components are derived as M_c = 0.717(14) M_⊙, M_h = 0.378(8) M_⊙, R_c = 0.708(12) R_⊙, R_h = 0.530(10) R_⊙, L_c = 0.138(12) L_⊙, and L_h = 0.085(7) L_⊙, respectively, and the distance of the system is estimated as 64(4) pc. The times of minima obtained in this study and with those published before enable us to calculate the mass transfer rate between the components which is 1.6 × 10^–8 M_⊙ yr^–1. Finally, we discuss the possible evolutionary scenario of CC Com (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Features around embedded moonlets in Saturn's rings: The role of self-gravity and particle size distributions

This paper presents the results of N-body simulations of moonlets embedded in broad rings, focusing specifically on the saturnian A ring. This work adds to previous efforts by including particle self-gravity and particle size distributions. The discussion here focuses primarily on the features that form in the background particles as a result of the moonlet. Particle self-gravity tends to damp out features produced by embedded moonlets and this damping is enhanced if the moonlet is simply the largest member of a continuous size distribution. Observable features around an embedded moonlet appear to require that the largest ring particles be no more massive than 1/30 the mass of the moonlet. These results, compared with current and future Cassini observations, will provide insight into the nature of the particle population in the saturnian rings. Some time is also spent analyzing the way in which the background particles cluster around the moonlet. The accretion of small particles onto the moonlet can be limited by disruptive collisions with the largest ring particles in the particle size distribution.     

Infrared photometry of Nova Delphini 2013 (=V339 Del) in the first sixty days after its outburst

The results of JHKLM photometry for Nova Delphini 2013 obtained in the first sixty days after its outburst are analyzed. Analysis of the energy distribution in a wide spectral range (0.36–5 µm) has shown that the source mimics the emission of normal supergiants of spectral types B5 and A0 for two dates near its optical brightness maximum, August 15.94 UT and August 16.86 UT, respectively. The distance to the nova has been estimated to be D ≈ 3 kpc. For these dates, the following parameters have been estimated: the source’s bolometric fluxes ～9 × 10^?7 and ～7.2 × 10^?7 erg s^?1 cm^?2, luminosities L ≈ 2.5 × 10⁵ L _⊙ and ≈2 × 10⁵ L _⊙, and radii R ≈ 6.3 × 10¹² and ≈1.2 × 10¹³ cm. The nova’s expansion velocity near its optical brightness maximum was ～700 km s^?1. An infrared (IR) excess associated with the formation of a dust shell is shown to have appeared in the energy distribution one month after the optical brightness maximum. The parameters of the dust component have been estimated for two dates of observations, JD2456557.28 (September 21, 2013) and JD2456577.18 (October 11, 2013). For these dates, the dust shell parameters have been estimated: the color temperatures ≈1500 and ≈1200 K, radii ≈6.5 × 10¹³ and 1.7 × 10¹⁴ cm, luminosities ～4 × 10³ L _⊙ and ～1.1 × 10⁴ L _⊙, and the dust mass ～1.6 × 10²⁴ and ～10²⁵ g. The total mass of the material ejected in twenty days (gas + dust) could reach ～1.1 × 10^?6 M _⊙. The rate of dust supply to the nova shell was ～8 × 10^?8 M _⊙ yr^?1. The expansion velocity of the dust shell was about 600 km s^?1.     

Relative Effect of Inclinations for Moonlets in the Triple Asteroidal Systems

We present the analysis and computational results for the inclination relative effect of moonlets of triple asteroidal systems. Perturbations on moonlets due to the primary’s non-sphericity gravity, the solar gravity, and moonlets’ relative gravity are discussed. The inclination vector for each moonlet follows a periodic elliptical motion; the motion period depends on the moonlet’s semi-major axis and the primary’s J2 perturbations. Perturbation on moonlets from the Solar gravity and moonlet’s relative gravity makes the motion of the x component of the inclination vector of moonlet 1 and the y component of the inclination vector of moonlet 2 to be periodic. The mean motion of x component and the y component of the inclination vector of each moonlet forms an ellipse. However, the instantaneous motion of x component and the y component of the inclination vector may be an elliptical disc due to the coupling effect of perturbation forces. Furthermore, the x component of the inclination vector of moonlet 1 and the y component of the inclination vector of moonlet 2 form a quasi-periodic motion. Numerical calculation of dynamical configurations of two triple asteroidal systems (216) Kleopatra and (153591) 2001 SN263 validates the conclusion.     

Chemical Evolution of Gas-Rich Galaxy Mergers

We investigate numerically the chemodynamical evolution of major disc–disc galaxy mergers in order to explore the origin of the mass-dependent chemical, photometric and spectroscopic properties observed in elliptical galaxies. We investigate especially the dependence of the fundamental properties on merger progenitor disc mass (M _d). Three main results are obtained in this study:– More massive (luminous) ellipticals formed by galaxy mergers between more massive spirals have higher metallicity (Z) and thus show redder colours; the typical metallicity ranges from ∼ 1.0 solar abundance (Z∼ 0.02) for ellipticals formed by mergers with M _d = 10¹⁰ M _⊙to ∼ 2.0 solar (Z∼ 0.04) for those with M _d= 10¹² M _⊙.– Both the Mg₂ line index in the central part of ellipticals (R ≤ 0.1 R _e) and the radial gradient of Mg₂ (δ Mg₂ / δ log R) are more likely to be larger for massive ellipticals. δ Mg₂ / δ log R correlates reasonably well with the central Mg₂ in ellipticals. For most of the present merger models, ellipticals show a positive radial gradient of the H_β line index. – Both M/L _B and M/L _K (where M, L _B, and L _K are the total stellar mass of galaxy mergers, the B-band and the K-band luminosities, respectively) depend on galactic mass in such a way that more massive ellipticals have larger M/L _B and smaller M/L _K. This revised version was published online in July 2006 with corrections to the Cover Date.     

Ages and masses of delta scuti stars in the praesepe cluster

Physical parameters and radial pulsation modes are determined for three Delta Scuti stars in the Praesepe cluster: HD 73345, HD 73712, and HD 73746. Their agest and evolutionary massesM _eare interpolated in the track systems of Iben (1967) and Paczyski (1970). By combining these age estimates with our previous results for nine other Delta Scuti-stars in the Praesepe cluster (Tsvetkov, 1989), the following weighted mean age estimates of this cluster are obtained: (14.2 ± 1.3) × 10⁸ yr (Iben) and (5.4 ± 0.4) × 10⁸ yr (Paczyski). Age and evolutionary mass estimates of the twelve cluster variables are also obtained in the modern track system of Maeder and Meynet (1988), in which the weighted mean cluster age is (15.3 ± 1.0) × 10⁸ yr.Pulsation massesM _Qcalculated from the fitting formulae of Faulkner (1977) and Fitch (1981) as well as massesM _g=gR ² / G were evaluated for the twelve cluster variables by Tsvetkov (1990) or in the present paper. In most cases there is a satisfactory agreement between our estimates of massesM _e,M _g, andM _Q.Due to a large disagreement between the long period and low luminosity of the star HD 73746, its radial pulsation mode and pulsation massM _Qcannot be evaluated.     

Supernova models with slow energy pumping and galactic supernova remnants

The study of supernova (SN) models with slow energy pumping is continued. At maximum luminosity the main characteristics of a SN are shown to be independent of the initial structure of the model (Table I, Figure 1). However, they depend on the massM _e of the envelope, and on the intensity of energy pumpingL , with an increase ofM _e leading qualitatively to the same changes in the SN parameters as a decrease inL (Table I, Figures 2 and 3). A simple relationship connecting the important SN parameters is obtained (Equation (6)). From the inflection of the color indexB-V curve, the possibility of deriving the characteristic time of energy pumping with intensityL 10⁴⁴ erg s^–1 is pointed out. The comparison of the extragalactic type I SN observations with the results of calculations leads to the estimate ofM _e 0.3–0.7M.An investigation of the galactic type I SN remnants is carried out (Table III). The estimate ofM _e 0.2–0.3M is obtained for the remnants of supernovae SN 1006, SN 1572, and SN 1604. It completely fits the results for the extragalactic type I SNs. The total initial mass of SN 1604 presupernova was shown to be at least about 7M .It was established that the Crab nebula resulted from the outburst of a peculiar SN. The unique properties of such SNs, including SN 1054, are due to the low intensity of energy pumping (L 10⁴² erg s^–1). The mass of the envelope of the Crab nebula is evaluated to beM _e 0.7M . SN 1054 was shown to have m _max ^v =–4 _m ^. 0 at maximum luminosity.     

Interacting galaxies in sparsely populated groups

We calculated the median values of the following parameters for 87 groups of galaxies with three to eight components: the mean rms velocity of the galaxies in the group, S _v = 166 km s^?1; the harmonic mean radius, R _h = 29 kpc; and the mass-to-light ratio, M _vir/L = 33 M _⊙/L _⊙. The M _vir/L ratio depends on the population of the system, while S _v does not depend on R _h. To ascertain the relationship between the activity of galaxies in groups and their morphological composition and the effect of the “environment” on the evolutionary processes in groups, we consider the fraction of galaxies with UV excess in the sample of interacting galaxies in groups (6%), single peculiar galaxies (8%), and isolated galaxies (4%) and their morphological composition. We also show that the number of active galaxies decreases with increasing population of the group of galaxies, while the frequency of occurrence of early-type (E/S0) galaxies increases.     

Helium emission in the middle chromosphere

Slitless spectrograms obtained during the eclipse of 10 June 1972 have been analyzed to determine the height distribution of the D₃ He line intensity.For undisturbed regions the maximum of D₃ line intensity is confirmed to exist at about 1700km above the limb. Besides the above mentioned maximum, in plages a considerable intensity may be observed at low heights (h < 1000 km).An analysis of these observations for h > 1000 km has been carried out within the low temperature mechanism of triplet helium emission taking into account the helium ionization by XUV radiation. The density dependence of the 2³ S level population at different XUV flux values has been calculated. Our observations give N _e 2 × 10¹⁰ cm^–3 in the chromosphere at h = 2000 km. The probable coincidence of the H and He emission small filaments in the middle chromosphere is discussed.     

Stellar Mass—Halo Mass Relation and Star Formation Efficiency in High-Mass Halos

We study relation between stellar mass and halo mass for high-mass halos using a sample of galaxy clusters with accurate measurements of stellar masses from optical and ifrared data and total masses from X-ray observations. We find that stellar mass of the brightest cluster galaxies (BCGs) scales as M_*,BCG ∝ M ₅₀₀ ^αBCG with the best fit slope of α_BCG ≈ 0.4 ± 0.1. We measure scatter of M_*,BCG at a fixed M₅₀₀ of ≈0.2 dex. We show that stellar mass-halo mass relations from abundance matching or halo modelling reported in recent studies underestimate masses of BCGs by a factor of ～2?4. We argue that this is because these studies used stellar mass functions (SMF) based on photometry that severely underestimates the outer surface brightness profiles of massive galaxies. We show that M_*?M relation derived using abundance matching with the recent SMF calibration by Bernardi et al. (2013) based on improved photometry is in a much better agreement with the relation we derive via direct calibration for observed clusters. The total stellar mass of galaxies correlates with total mass M₅₀₀ with the slope of ≈0.6 ± 0.1 and scatter of 0.1 dex. This indicates that efficiency with which baryons are converted into stars decreases with increasing cluster mass. The low scatter is due to large contribution of satellite galaxies: the stellar mass in satellite galaxies correlates with M₅₀₀ with scatter of ≈0.1 dex and best fit slope of α_sat ≈ 0.8 ± 0.1. We show that for a fixed choice of the initial mass function (IMF) total stellar fraction in clusters is only a factor of 3?5 lower than the peak stellar fraction reached in M ≈ 10¹²M_⊙ halos. The difference is only a factor of ～1.5?3 if the IMF becomes progressively more bottom heavy with increasing mass in early type galaxies, as indicated by recent observational analyses. This means that the overall efficiency of star formation in massive halos is only moderately suppressed compared to L_* galaxies and is considerably less suppressed than previously thought. The larger normalization and slope of the M_*?M relation derived in this study shows that feedback and associated suppression of star formation in massive halos should be weaker than assumed in most of the current semi-analytic models and simulations.     

Absolute dimensions of the close binary systems V453 Monocerotis and V523 Cassiopeiae

We present multi-colour CCD observations of the low-temperature contact binaries, V453 Mon and V523 Cas. Their light curves are modelled to determine a new set of stellar and orbital parameters. Analysis of mid-eclipse times yields a new linear ephemeris for both systems. A period decrease (dP/dt=2.3×10⁻⁷ days/yr) in V453 Mon is discovered. V523 Cas, however, is detected to show a period increase (dP/dt=9.8×10⁻⁸ days/yr) because of the mass transfer of a rate of 1.1×10⁻⁷ M_⊙ yr⁻¹, from a less massive donor. Using these findings we can determine the physical parameters of the components of V523 Cas to be M ₁=0.76 (3)M _⊙, M ₂=0.39 (2)M _⊙, R ₁=0.74 (2)R _⊙, R ₂=0.55 (2)R _⊙, L ₁=0.19 (3)L _⊙, L ₂=0.14 (3)L _⊙, and the distance of system as 46(9) pc.     

Astrometric study of the relative motion of three stars with possible invisible companions based on homogeneous series obtained at Pulkovo with a 26-inch refractor

We investigate the relative motion of three stars, ADS 7446, 9346, and 9701, based on long-term observations with the Pulkovo 26-inch refractor. The relative motion of all three stars shows a perturbation that could be produced by the gravitational influence of an invisible companion. For ADS 7446, we have determined the orbit of the photocenter with a period of 7.9 yr; the mass of the companion is more than 0.4M _⊙. For ADS 9346, we have determined the radial velocities of the components: −14.60 km s⁻¹ for A and −13.94 km s⁻¹ for B. For ADS 9346 and 9701, we have determined the dynamical parallaxes, 24 and 20 mas, respectively, which are larger than those in the Hipparcos catalog by 5 mas, and calculated the orbits by the apparent motion parameter (AMP) method. The new orbit of ADS 9346 is: a = 5″.2, P = 2035 yr, and e = 0.46 at the system’s mass M = 2.5M _⊙. The new orbits of ADS 9701 are: (a = 2″.9, P = 829 yr, e = 0.54, M = 4.3M _⊙) and (a = 3″.8, P = 1157 yr, e = 0.53, M = 5.0M _⊙).     

A simple way to classify supermassive black holes

We propose a classification of supermassive black holes (SMBHs) based on their efficiency in the conversion of infalling mass in emitted radiation. We use a theoretical model that assumes a conservation of angular momentum between the gas falling inside the hole and the photons emitted outwards, and suggests the existence of the scaling relation M_•‐R_eσ³, where M_• is the mass of the central SMBH, whereas R_e and σ are the effective radius and velocity dispersion of the host galaxies (bulges), respectively. We apply our model on a data set of 57 galaxies of different morphological types and with M_• measurements, obtained through the analysis of Spitzer /IRAC 3.6‐µ m images. In order to find the best fit of the corresponding scaling law, we use the FITEXY routine to perform a least‐squares regression of M_• on R_eσ³ for the considered sample of galaxies. Our analysis shows that the relation is tight and our theoretical model allows to easily estimate the efficiency of mass conversion into radiation of the central SMBHs. Finally we propose a new appealing way to classify the SMBHs in terms of this parameter. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The elliptical three-body problem. Triangular solution

The restricted three-body problem with eccentric orbit is reviewed and the positions of the triangular Lagrangian points (L₄, L₅) are determined. It is put in evidence the fact the fact L₄ and L₅ are situated at the corners of an isoscales triangle: AB = BC = 1 − e²/)1 + e cos ν )4/3 and AC = 1 − e²/)1 + e cos ν )     

Physical conditions of ionized gas and mass-luminosity distribution in NGC 7793

The physical state of ionized gas in NGC 7793 was studied by spectroscopical means: the electronic temperature isT _e10⁴K while the electronic density ranges fromN _e1400 cm^–3 in the nucleus toN _e1000 cm^–3 in the emission regions. There are also indications of an excess of nitrogen in the nucleus. TheM/L ratio suggests for NGC 7793, a high proportion of young objects quite uniformly distributed over its body, with a slight concentration towards the nuclear region.     

Heterogeneous condensation of presolar titanium carbide core‐graphite mantle spherules

Abstract— We investigate heterogeneous nucleation and growth of graphite on precondensed TiC grains in the gas outflows from carbon‐rich asymptotic giant branch (AGB) stars employing a newly‐derived heterogeneous nucleation rate taking into account of the chemical reactions at condensation. Competition between heterogeneous and homogeneous nucleations and growths of graphite is investigated to reveal the formation conditions of the TiC core‐graphite mantle spherules found in the Murchison meteorite. It is shown that no homogeneous graphite grain condenses whenever TiC condenses prior to graphite in the plausible ranges of the stellar parameters. Heterogeneous condensation of graphite occurs on the surfaces of growing TiC grains, and prevents the TiC cores from reaching the sizes realized if all available Ti atoms were incorporated into TiC grains. The physical conditions at the formation sites of the TiC core‐graphite mantle spherules observed in the Murchison meteorite are expressed by the relation 0.2 < n?_0.1 (M₅/ζ)^?1/2L₄^1/4 < 0.7, where v_0.1 is the gas outflow velocity at the formation site in units of 0.1 km s^?1, M₅ the mass loss rate in 10^?5 M⊙ year^?1, L₄ the stellar luminosity in 10⁴ L⊙, and M/ζ is the effective mass loss rate taking account of non‐spherical symmetry of the gas outflows. The total gas pressures P_c at the formation sites for the effective mass loss rates M/ζ = 10^?5‐10^?3 M⊙ year^?1 correspond to 0.01 < P_c < 0.9 dyn cm^?2, implying that the observed TiC core‐graphite mantle spherules are formed not only at the superwind stage but also at the earlier stage of low mass loss rates. The constraint on the C/O abundance ratio, 1 < ? ? 1.03, is imposed to reproduce the observed sizes of the TiC cores. The derived upper limit of the C/O ratio is lower than the values estimated from the calculations without taking into account of heterogeneous condensation of graphite, and is close to the lower end of the C/O ratios inferred from the astronomical observations of carbon‐rich AGB stars. Brief discussion is given on other types of graphite spherules.     

Main stages of evolution of matter in the universe. II

A possible scenario for the evolution of the universe following the big bang at t > 10^-5 sec is considered. The necessary conditions that must be present for the formation of stars and stellar systems to be possible are formulated. As a condition for the formation of stars we take kT_s≤ GM_sm_p(3R), and for stellar systems HR ? (GM/R)^1/2, where T_s is the temperature of the cosmic plasma, m_p is the mass of a proton, M_s is the mass of a star, M is the mass of a stellar cluster, R is the radius of these celestial bodies, and H is the bubble parameter for the corresponding time. In accordance with these criteria, we assume that in the course of cosmological expansion, neutron stars should have been formed first (times 2.10^-4 ? t ? 1 sec, densities 0.07 ? ρ_B? 2.10⁴ g/cm³) and then, in chronological order, appeared white dwarfs (t ≈ 10² sec, ρ_B ? 5.10^-3 g/cm³), ordinary stars (t ≈ 4.10⁶ sec, ?_B ≈ 10^-11 g/cm³), galactic nuclei (t ≈ 3.10¹¹ sec, ?_B ≈ 5.10^-19 g/cm³, globular clusters (t ≈ 10¹³ sec, ?_B ≈ 4.10^-21 g/cm³), and galaxies (t ≈ 10¹⁵ sec, ?_B ≈ 10^-24 g/cm³), where ?_B is the average density of ordinary (baryon) matter in the universe. It is shown that a galactic nucleus is a stellar system in statistical equilibrium and consists mainly of neutron stars and white dwarfs. The formation of some pulsars (neutron stars with angular rotation rates 1 < Ω < 200 sec^-1) may occur in a galactic nucleus. Observed pulsars should therefore contain some fraction of neutron stars from the nucleus of the Galaxy that were able to escape it over the relaxation time (the tail of the Maxwell distribution, with star velocities v > v₀, where v₀ is the velocity corresponding to the work function 2GMM_s/R, M being the mass and R the radius of the Galaxy’s nucleus.     

Eddingtons Zahlen,Einsteins Kriterium und Rydbergs rationelles Dimensionssystem

The discussions about the meaning of the “hierarchy of interactions” and in connection with this about the role of Eddington's “cosmological number” imply the question of the “big numbers” in physics. According to Einstein's and Bridgman's criteria such “big numbers” are hints at unsolved problems in the foundations of physics. Eddington gives a theory of the big number like cosmological quantities. – A new point of view on this question may be to remember Rydberg's suggestion on independigly physical dimensions of lengths L, surfaces S, and volumina V, and to remember Dällenbach's suggestion to introduce a new universal constant α which describes the operational connections between the quardrate of lengths L² and the surface S in microphysics. Coulomb's and Nwton's laws have the same structure. But, the electrical forces are depending on L^-2 and the gravitational forces are depending on S^-1 ∼ (1/α) L^-2 because “gravitation is geometry”. In Planck's elementary units h, c and f Dällenbach's “surface-constant of the vacuum” α is a pure number α ≈ hc/fm², th. i. Eddington's cosmological number ω ∼ 10⁴⁰. However, Rydberg's physical dimensions in geometry and Dällenbach's constant suggest new formulations of the question of “geometrization of physics” and “physicallization of geometry” and the connections between cosmology and microphysics.