RC J0311+0507: A candidate for superpowerful radio galaxies in the early universe at redshift z = 4.514     

A. I. Kopylov  W. M. Goss  Yu. N. Pariĭskiĭ  N. S. Soboleva  O. V. Verkhodanov  A. V. Temirova  O. P. Zhelenkova 《Astronomy Letters》2006,32(7):433-438

A strong emission line at 6703 Å has been detected in the optical spectrum for the host galaxy (R = 23.1) of the radio source RC J0311+0507 (4C+04.11). This radio galaxy, with a spectral index of 1.31 in the frequency range 365–4850 MHz, is one of the ultrasteep-spectrum objects from the deep survey of a sky strip conducted with RATAN-600 in 1980–1981. We present arguments in favor of the identification of this line with Lyα at redshift z = 4.514. In this case, the object belongs to the group of extremely distant radio galaxies of ultrahigh radio luminosity (P ₁₄₀₀ = 1.3 × 10²⁹ W Hz^?1). Such power can be provided only by a fairly massive black hole (～10⁹ M⊙) that formed in a time less than the age of the Universe at the observed z (1.3 Gyr) or had a primordial origin.  相似文献   

Regional dynamics of socio-economic change —The experiences and prospects in sparsely populated areas     

Antoni Kukliński Prof. Dr. 《GeoJournal》1986,12(1):107-110

  相似文献   

Black hole spin in GRS 1915+105   总被引：2，自引：0，他引：2  

Matthew Middleton  Chris Done  Marek Gierli&#;ski  Shane W. Davis 《Monthly notices of the Royal Astronomical Society》2006,373(3):1004-1012

  相似文献   

Statistical characteristics of the observed Lyα forest and the shape of the initial power spectrum     

M. Demia&#;ski  A. G. Doroshkevich  V. I. Turchaninov 《Monthly notices of the Royal Astronomical Society》2006,371(2):915-934

  相似文献   

Be star candidates in the Large Magellanic Cloud: the catalogue and comparison with the Small Magellanic Cloud sample     

B. E. Sabogal  R. E. Mennickent  G. Pietrzy&#;ski  W. Gieren 《Monthly notices of the Royal Astronomical Society》2005,361(3):1055-1062

We present a catalogue with coordinates and photometric data of 2446 Be star candidates in the Large Magellanic Cloud (LMC), based on a search of the OGLE II data base. The I -band light curves of these stars show outbursts in 24 per cent of the sample (Type-1 stars), high and low states in 10 per cent, periodic variations in 6 per cent (Type-3 stars), and stochastic variations in 60 per cent of the cases. We report on the result of the statistical study of light curves of Type-1 and Type-3 stars in the LMC, and the comparison with the previously reported results of the Small Magellanic Cloud (SMC) sample. We find a statistically significant difference between amplitude, duration and asymmetry distributions of outbursts in both galaxies. Outbursts of SMC Type-1 stars are usually brighter, longer and with a slower decline. We find a bimodal distribution of periods of Type-3 stars in both galaxies, probably related to the recently discovered double periodic blue variables. We find also period and amplitude distributions of Type-3 LMC stars statistically different from those of the SMC stars. Our findings above suggest that the mechanisms causing the observed photometric variability of Type-1 and Type-3 stars could depend on metallicity. Moreover, they suggest that the outbursts are not primarily caused by stellar winds.  相似文献   

GRS 1915+105: the brightest Galactic black hole     

Chris Done  Grzegorz Wardzi&#;ski  Marek Gierli&#;ski 《Monthly notices of the Royal Astronomical Society》2004,349(2):393-403

  相似文献   

Mechanics of a sandy subsoil subjected to cyclic loadings     

Andrzej Sawicki  Waldemar Swidzinski 《国际地质力学数值与分析法杂志》1989,13(5):511-529

A simple model for compaction of a sand, that may be useful in various geotechnical applications is presented. The model has been formulated in terms of the cyclic stress and strain amplitudes. The compaction properties of a dry sand are characterized by a common compaction curve described by two coefficients. The second aim of this paper is to show some applications of the theory proposed. The attention has been restricted to the two extreme cases of practical importance, namely to the behaviour of a dry sand (or a saturated sand but in free draining conditions), and to the behaviour of saturated sand in undrained conditions. Some numerical algorithms showing how to deal with those problems are presented and illustrated on the following examples: settlement and pore pressure generation in a soil stratum subjected to an earthquake, settlement of a foundation, pore pressure generation and liquefaction in a sea-bed. The results obtained suggest that the model proposed, as well as a method of dealing with boundary value problems can serve as a useful tool for the analysis of a sandy subsoil subjected to cyclic loadings.  相似文献   

Book reviews     

Roy  B. K.  Stanley  William R.  Bronger  Dirk  Dlin  Norman  Kukliński  Antoni  Cori  Berardo  Babikir  A. A. A.  Kunkel  G.  César  N.  Martin  Kähler 《GeoJournal》1989,18(2):255-260

  相似文献   

Tides and Arp's hypothesis about distribution of Hii regions     

Teresa Grabińska  Mirosław Zabierowski 《Astrophysics and Space Science》1979,66(2):503-504

We discuss Arp's hypothesis that the HII regions are more numerous and more conspicuous on the side of a galaxy facing its companion. Arp's hypothesis seems not to be true if we add to Hodge's sets of galaxies only the most probably tidally-interacting cases.  相似文献   

Discovery of powerful millisecond flares from Cygnus X-1     

Marek Gierli&#;ski  Andrzej A. Zdziarski 《Monthly notices of the Royal Astronomical Society》2003,343(3):L84-L88

  相似文献