Filters
Results 1 - 10 of 63454
Results 1 - 10 of 63454.
Search took: 0.056 seconds
Sort by: date | relevance |
AbstractAbstract
[en] A series of disc galaxy models are constructed and their deformation in the tidal interaction is investigated by N-body simulations. Each galaxy model is composed of a self-gravitating disc made up of many particles and a rigid halo component added to stabilize the disc. Each model is characterized by two parameters; the mass fraction of the disc and the mass concentration of the halo toward the centre. These parameters are widely varied to investigate the dependence on internal structure whereas the relative motions of two galaxies are restricted to parabolic prograde planar encounters. It is found that the self-gravitating discs, when perturbed by the tidal force of another galaxy, develop prominent spiral structures not only in the outer region but also in the inner region. This is a remarkable contrast to the case of the massless discs constructed by test particles, in which only the outer part exhibits a spiral structure. (author)
Primary Subject
Record Type
Journal Article
Journal
Monthly Notices of the Royal Astronomical Society; ISSN 0035-8711;
; CODEN MNRAA; v. 228(3); p. 635-651

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The results are given of detailed UBV photometry of the peculiar galaxy NGC 2685 based on 10 negatives obtained with the 2.6-m telescope of the Biurakan Observatory. Consideration of all the available observational data (photometric, spectroscopic, and polarization) suggests that NGC 2685 is a pair of colliding galaxies. 18 references
Primary Subject
Source
Cover-to-cover translation of Astrofizika (USSR).
Record Type
Journal Article
Journal
Astrophysics (Engl. Transl.); ISSN 0004-6396;
; v. 19 p. 325-333

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The structural properties of the dwarf spheroidal satellite galaxies of the Milky Way may be strongly affected by their time-dependent interactions with the tidal field of the Milky Way. A low Q resonance of the tidal driving force with collective oscillation modes of the dwarf system can produce many of the observed properties of the Local Group dwarf spheroidal galaxies, including large velocity dispersions that would normally be interpreted as indicating large dynamical masses. 18 refs
Primary Subject
Record Type
Journal Article
Journal
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] We propose a new mechanism by means of which a phase transition can be stimulated by self-gravitating matter. We suggest that this model could be used to explain the observed isotropy of the Universe. (orig.)
Primary Subject
Record Type
Journal Article
Journal
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Mapoles, E.R.
Stanford Univ., CA (USA)1981
Stanford Univ., CA (USA)1981
AbstractAbstract
[en] The inverse square law of gravitation is known to agree with astronomical data to very high accuracy, but recent theoretical and experimental work indicate that the inverse square law may be violated at distances less than 100 km. Such a violation would signal the existence of a new force. In order to check the inverse square law we are preparing to search for a non-newtonian force in a cylindrical shell. The cyclindrical shell has the property that the newtonian effects nearly cancel, so that we are doing a nearly null experiment. We have developed a superconducting gradiometer to measure the gravitational force gradients at the center of this cylindrical shell. By measuring both the vertical and horizontal gradients we can eliminate effects due to imperfections in the cylinder. This thesis describes the instrument and its performance as well as calculations of the sensitivity of the inverse square law test
Primary Subject
Secondary Subject
Source
1981; 126 p; University Microfilms Order No. 82-02,017; Thesis (Ph. D.).
Record Type
Report
Literature Type
Thesis/Dissertation
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Accioly, A.J.; Goncalves, A.T.
Sao Paulo Univ. (Brazil). Inst. de Fisica1986
Sao Paulo Univ. (Brazil). Inst. de Fisica1986
AbstractAbstract
[en] A scalar-tensor theory of fourth-order gravity is considered. Some cosmological consequences, due to the presence of the scalar field, as well as of metric derivatives higher than second order, are analysed. In particular, upperbpunds are obtained for the coupling constant α and for the scale factor of the universe, respectively. The discussion is restricted to Robertson-Walker universes. (Author)
[pt]
Uma teoria escalar-tensorial da gravidade da quarta-ordem e considerada. Algumas consequencias cosmologicas, devido a presenca do campo escalar, bem como de derivadas metricas superiores a segunda ordem, sao analisadas. Em particular, limites superiores sao obtido para a constante de acoplamento α e para o fator de escala do universo, respectivamente. A discussao esta restrita a Universos de Robertson-Walker. (S.D.)Primary Subject
Source
Apr 1986; 6 p
Record Type
Report
Report Number
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The possible formation of bound hierarchical triple systems in globular clusters by encounters between single stars and binaries formed by tidal capture is considered. The first step in forming such systems must be the formation of temporarily bound hierarchical resonances. This paper explores the creation of such resonance systems in the context of globular clusters, taking into account both point mass and tidal effects. Numerical simulations show that relatively long-lasting systems can be formed, but only in retrograde or near retrograde orbits. A total cross section for the formation of relatively long-lasting triples on the order of that for the formation of tidal capture binaries is determined. The very low energy of the incoming stars appropriate for interactions in globular clusters is crucial for the formation process. 33 refs
Primary Subject
Record Type
Journal Article
Journal
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] We have conducted an experiment to detect a composition-dependent force with range λ between 10 m and 1 km, and find a statistically significant effect. If interpreted as arising from a new force, this result and other recent measurementes would be consistent in strength only if the coupling were predominantly to nuclear isospin
Primary Subject
Record Type
Journal Article
Journal
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Markov, M.A.
The very early universe. Proceedings of the Nuffield Workshop, Cambridge, 21 June to 9 July, 19821983
The very early universe. Proceedings of the Nuffield Workshop, Cambridge, 21 June to 9 July, 19821983
AbstractAbstract
[en] Specific features of a perpetually oscillating universe are considered. In a perpetually oscillating universe there is no problem of origination of the world, which in other versions of the universe may appear to be unsolvable. In the first section, the solution of the singularity problem is associated with the possible existence of asymptotic freedom for gravitational interactions. In the second section, the final state of a black hole is assumed to be a stable particle (maximon) of Planck mass and dimensions. (author)
Primary Subject
Source
Gibbons, G.W.; Hawking, S.W. (Cambridge Univ. (UK). Dept. of Applied Mathematics and Theoretical Physics); Siklos, S.T.C. (Cambridge Univ. (UK)) (eds.); 484 p; ISBN 0 521 25349 7;
; 1983; p. 353-371; Cambridge University Press; Cambridge (UK); Nuffield workshop; Cambridge (UK); 21 Jun - 9 Jul 1982

Record Type
Book
Literature Type
Conference
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
No abstract available
Primary Subject
Record Type
Journal Article
Journal
J. Math. Phys. (N.Y.); v. 15(5); p. 640-642
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
1 | 2 | 3 | Next |