INTERPRETATION OF OPTICAL AND IR LIGHT CURVES FOR TRANSITIONAL DISK CANDIDATES IN NGC 2264 USING THE EXTINCTED STELLAR RADIATION AND THE EMISSION OF OPTICALLY THIN DUST INSIDE THE HOLE

In the stellar forming region NGC 2264 there are objects catalogued as hosting a transitional disk according to spectrum modeling. Four members of this set have optical and infrared light curves coming from the CoRoT and Spitzer telescopes. In this work, we try to simultaneously explain the light curves using the extinction of the stellar radiation and the emission of the dust inside the hole of a transitional disk. For the object Mon-296, we were successful. However, for Mon-314, and Mon-433 our evidence suggests that they host a pre-transitional disk. For Mon-1308 a new spectrum fitting using the 3D radiative transfer code Hyperion allows us to conclude that this object hosts a full disk instead of a transitional disk. This is in accord to previous work on Mon-1308 and with the fact that we cannot find a fit for the light curves using only the contribution of the dust inside the hole of a transitional disk.

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Analysis of Optical and IR Light Curves of the Wr Binary V444 Cygni: Are Clumps Still Present?

Instability and Variability of Hot-Star Winds ◽

10.1007/978-94-011-0315-2_18 ◽

1994 ◽

pp. 239-248

Author(s):

I. Antokhin

Keyword(s):

Light Curves ◽

Ir Light

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Ploonets: formation, evolution, and detectability of tidally detached exomoons

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2110 ◽

2019 ◽

Vol 489 (2) ◽

pp. 2313-2322 ◽

Cited By ~ 6

Author(s):

Mario Sucerquia ◽

Jaime A Alvarado-Montes ◽

Jorge I Zuluaga ◽

Nicolás Cuello ◽

Cristian Giuppone

Keyword(s):

Planetary System ◽

Orbital Evolution ◽

Giant Planets ◽

Light Curves ◽

Significant Evidence ◽

Object A ◽

Tidal Interactions ◽

Stellar Radiation ◽

Planetary Migration ◽

Intense Research

Abstract Close-in giant planets represent the most significant evidence of planetary migration. If large exomoons form around migrating giant planets which are more stable (e.g. those in the Solar system), what happens to these moons after migration is still under intense research. This paper explores the scenario where large regular exomoons escape after tidal interchange of angular momentum with its parent planet, becoming small planets by themselves. We name this hypothetical type of object a ploonet. By performing semi-analytical simulations of tidal interactions between a large moon with a close-in giant, and integrating numerically their orbits for several Myr, we found that in ∼50 per cent of the cases a young ploonet may survive ejection from the planetary system, or collision with its parent planet and host star, being in principle detectable. Volatile-rich ploonets are dramatically affected by stellar radiation during both planetocentric and siderocentric orbital evolution, and their radius and mass change significantly due to the sublimation of most of their material during time-scales of hundreds of Myr. We estimate the photometric signatures that ploonets may produce if they transit the star during the phase of evaporation, and compare them with noisy light curves of known objects (Kronian stars and non-periodical dips in dusty light curves). Additionally, the typical transit timing variations (TTV) induced by the interaction of a ploonet with its planet are computed. We find that present and future photometric surveys’ capabilities can detect these effects and distinguish them from those produced by other nearby planetary encounters.

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Interpreting the Evolving Clumpy Shell Structure of IRC +10216 in Terms of Time Dependent Dust Shell Models

Symposium - International Astronomical Union ◽

10.1017/s0074180900208292 ◽

2003 ◽

Vol 209 ◽

pp. 127-128

Author(s):

J. M. Winters ◽

T. Blöcker ◽

K.-H. Hofmann ◽

G. Weigelt

Keyword(s):

Time Scale ◽

High Spatial Resolution ◽

Light Curves ◽

Infrared Light ◽

Pulsation Period ◽

Line Profiles ◽

Dust Shell ◽

Time Intervals ◽

Stellar Pulsation ◽

Shell Models

The prototypical dust-enshrouded carbon Mira IRC +10216 is known to exhibit intrinsic changes on a time scale of the order of only a few years as revealed, e.g., by CO infrared line profiles (Winters et al. 2000a), its infrared light curves, and by high spatial resolution monitoring in the infrared (Osterbart et al. 2000; Tuthill et al. 2000). In particular, the infrared light curves indicate a possible periodicity on a ≈ 20 yr time scale, i.e. that a recurrent phenomenon might lead to the observed variations. Such multi-periodicity time scales of several (≈ 10) stellar pulsation periods are predicted by consistent hydrodynamical models which include a proper treatment of dust formation (e.g. Winters et al. 2000b). In these models discrete dust layers form in time intervals which are several times longer than the typical pulsation period of an AGB star (Fleischer, Gauger, & Sedlmayr 1995; Höfner, Feuchtinger, & Dorfi 1995).

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NEAR-INFRARED LIGHT CURVES OF THE BROWN DWARF ECLIPSING BINARY 2MASS J05352184-0546085: CAN SPOTS EXPLAIN THE TEMPERATURE REVERSAL?

The Astrophysical Journal ◽

10.1088/0004-637x/699/2/1196 ◽

2009 ◽

Vol 699 (2) ◽

pp. 1196-1208 ◽

Cited By ~ 19

Author(s):

Yilen Gómez Maqueo Chew ◽

Keivan G. Stassun ◽

Andrej Prša ◽

Robert D. Mathieu

Keyword(s):

Near Infrared ◽

Light Curves ◽

Infrared Light ◽

Brown Dwarf ◽

Near Infrared Light ◽

Eclipsing Binary

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The influence of line opacity treatment in stella on supernova light curves

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2704 ◽

2020 ◽

Vol 499 (3) ◽

pp. 4312-4324

Author(s):

Alexandra Kozyreva ◽

Luke Shingles ◽

Alexey Mironov ◽

Petr Baklanov ◽

Sergey Blinnikov

Keyword(s):

Radiative Transfer ◽

Spectral Synthesis ◽

Broad Band ◽

Light Curves ◽

Radiation Hydrodynamics ◽

Type Ii ◽

Type Ia ◽

The Impact ◽

Supernovae Type Ia

ABSTRACT We systematically explore the effect of the treatment of line opacity on supernova light curves. We find that it is important to consider line opacity for both scattering and absorption (i.e. thermalization, which mimics the effect of fluorescence). We explore the impact of the degree of thermalization on three major types of supernovae: Type Ia, Type II-peculiar, and Type II-plateau. For this we use the radiative transfer code stella and analyse broad-band light curves in the context of simulations done with the spectral synthesis code artis and in the context of a few examples of observed supernovae of each type. We found that the plausible range for the ratio between absorption and scattering in the radiation hydrodynamics code stella is (0.8–1):(0.2–0), i.e. the recommended thermalization parameter is 0.9.

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Theoretical UBVI Light Curves of Pulsating Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100058012 ◽

2000 ◽

Vol 176 ◽

pp. 334-337

Author(s):

Michael U. Feuchtinger ◽

Ernst A. Dorfi

Keyword(s):

Radiative Transfer ◽

Light Curves ◽

Rr Lyrae Stars ◽

Fourier Decomposition ◽

Pulsating Stars ◽

Rr Lyrae ◽

Stellar Pulsation ◽

Sample Application ◽

Lyrae Stars ◽

Good Agreement

AbstractBy performing detailed frequency-dependent radiative transfer computations we are able to calculate light curves in particular bandpasses from stellar pulsation models calculated by the Vienna nonlinear convective pulsation code. As a sample application we discuss UBVI light curves of RR Lyrae stars. The properties of these light curves are analyzed by means of standard Fourier decomposition, and a comparison to recent observations is performed. As main results we find a good agreement with important observed RR Lyrae properties like pulsation amplitudes and Fourier parameters in B, V, and I bands. Additionally, from the synthetic color curves we derive linear transformation laws between amplitudes as well as Fourier parameters in the different bandpasses.

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