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Sholomitskii, G. B.

doi:10.1023/a:1000882603638

Cited by 3 publications

(3 citation statements)

References 13 publications

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“…Light echoes have been considered in connection with gamma-ray bursts (Reichart 2001;Band & Hartmann 1992) and active galactic nuclei (de Diego et al 1998), as distance indicators to galaxy clusters (Milgrom 1987;Katz 1987;Braun & Milgrom 1989), and for probing the baryon density of the universe with high-z sources (Sholomitskii 1997). If nearly-90 • scattering occurs, the positions of maximally-polarized echoes yield geometric distance measurements to the echo source (Sparks 1994(Sparks , 1996.…”

Section: Introductionmentioning

confidence: 99%

Observability of Scattered-Light Echoes around Variable Stars and Cataclysmic Events

Sugerman

2003

Astron J

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Scattered-light echoes from variable and cataclysmic stars offer one of the most effective means to probe the structure and composition of circumstellar and interstellar media. I build a simple model of light-echo surface brightness by considering the source spectrum and the dust density, geometry, and scattering efficiency. I use this model to investigate whether echoes should be observable around short and long-period giants, cataclysmic variables, and supernovae. Only supernovae are expected to illuminate material on both circumstellar and interstellar scales. Giant and post-AGB stars (e.g., Cepheids and Miras) with high mass-loss rates can produce observable echoes within their circumstellar envelopes. Echoes from novae and dwarf novae are probably detectable only from nearby material, and only in unusually dense gas. I present characteristic exposure times to image such echoes over a wide range of wavelengths for ground-based and Hubble Space Telescope observations. I apply these results to analyze the dust properties of the recently reported echoes around SN 1993J, finding the dust in M81 to have a grain-size distribution and chemical composition consistent with Galactic dust. Optimal observing strategies for echo detection are also discussed.

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Section: Introductionmentioning

confidence: 99%

Observability of Scattered-Light Echoes around Variable Stars and Cataclysmic Events

Sugerman

2003

Astron J

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“…As discussed by many authors (Fukuda et al 1998, Turner 1999), only about one-tenth of the baryons are visible in the form of bright stars. At very large red shifts, according to the latest data on Light Echoes of radio sources, the baryonic density of the Universe is still lower and comes to only ∼ 0.001 of the total (Sholomitskii 1997). From the empirical standpoint, this may support the argument that some fraction of dark matter in the Universe exists in the form of PBHs.…”

Section: Capture and Incorporationmentioning

confidence: 99%

Singular Sources of Energy in Stars and Planets

Zhilyaev

2007

Preprint

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If primordial low-mass black holes (PBH) exist in the Universe than many of stars and planetary bodies appear to be "infected" by them. This is also true in regard to the Sun and likely Jupiter and Saturn. The availability of even the very low-mass inner relativistic reactor may lead to essential changes in evolution scenario of a celestial body on its lifetime scale. Black holes in stellar interior may be found either in consequence of captures process or incorporation during the formation of a star from interstellar clouds. Surprisingly that in the equilibrium state a PBH growth is a long-lived process with e-folding rise time of billion years. One can envision a PBH orbiting inside the Sun. Our considerations showed that the PBH experiences very little friction in passing through the stellar matter. If the BH mass is above 10 −5 M ⊙ the major contribution to the luminosity comes from the relativistic gravitational reactor. In such a case a star evolves towards the Eddington limit. This should lead to considerable expansion of a star and a global stability loss. Microscopic PBHs can exist in the interior of planetary bodies too. To produce the required excess of thermal energy on Jupiter and Saturn the masses of PBH captured are assumed to be reached of 4 • 10 19 and 7 • 10 18 g , respectively. These microscopic objects are comparable to the hydrogen atom in size. One can envision even a planet with the PBH acting as the self-sufficient source of heating. Such a planet does not need a sun to maintain animal life on its surface. This may last eons.keywords black hole physics -(stars:) planetary systems -Solar system: general BASIC CONCEPTIs it the case that a small black hole captured inside a star causes its collapse? That is not the case, otherwise, if such a situation would be present that should produce observable signatures in the form of supernova explosions at a fantastic rate as will be seen below. Hawking (1971) first pointed out that gravitationally collapsed objects, which were formed in the early Universe, could have accumulated at the center of a star like the Sun. The presence of such a hypothetical situation requires a more detailed consideration.Following Beckenstein (1974) and Sciama (1976), one can consider the BH in thermostat as a heat engine with an available thermodynamic efficiency of (2 − √ 2) = 0.59. Such a relativistic reactor may be competitive in power with the nuclear burning. Here we attempt to answer the questions: (1) where are BHs from in stellar interior? (2) how does this feature change the stellar structure and evolution? (3) may one expect some observable signatures of this feature in the Universe?

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“…Variability studies of AGN, in particular of the extreme blazar class, have proven to be powerful tools for the investigation of the nature of these objects. Shortly after the discovery of quasars the observation of variability of their radio fluxes on time scales of a few months [10,4] led to the inference of relativistic bulk motion [9,13] and consequently fuelled the development of the relativistic jet model [2]. Short term variability on time scales of a day (intraday variability, IDV see review [11]) provides even stronger constraints on the source size and the physical conditions.…”

Section: Introductionmentioning

confidence: 99%

Intensive monitoring of the strongly variable BL Lac S5 0716+714

Otterbein¹,

Hardcastle

Wagner³

et al. 1999

Nuclear Physics B - Proceedings Supplements

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The BL Lac object S5 0716+714 was monitored during a multifrequency campaign in 1996. Preliminary analysis of the optical, ROSAT and RXTE data are presented. Strong variability on short time scales was observed. The data suggest an interpretation within a multi-component model.Comment: To appear in The Active X-ray Sky: Results from BeppoSAX and Rossi-XTE, Rome, Italy, 21-24 October, 1997. Eds.: L. Scarsi, Bradt, P. Giommi and F. Fiore. PS-file avialable at http://www.lsw.uni-heidelberg.de/projects/extragalactic/bl_lac.htm

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Cited by 3 publications

References 13 publications

Observability of Scattered-Light Echoes around Variable Stars and Cataclysmic Events

Observability of Scattered-Light Echoes around Variable Stars and Cataclysmic Events

Singular Sources of Energy in Stars and Planets

Intensive monitoring of the strongly variable BL Lac S5 0716+714

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