On the observability of extrasolar planetary systems

Argyle, Edward

doi:10.1016/0019-1035(74)90138-9

Cited by 8 publications

(11 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the event that we only have a time series, without velocity, positional, or polarimetric corroborating observations, or if the flare duration is longer than the light travel time to the planet, we can employ more sophisticated mathematical methods to identify the presence of a faint echo of the primary light curve, delayed by the light travel time to the planet. The most straightforward approach is probably auto-or cross-correlation in the time dimension (Argyle 1974;Sparks & Ford 2002;Snellen et al 2013Snellen et al , 2015. An extension of this algorithmic approach could be an autocorrelation with a variable time lag that depends on the orbital phase.…”

Section: (6) Putting It All Togethermentioning

confidence: 99%

“…We propose to turn the tables and use the flares as a probe, taking advantage of the short, bright impulse of light from the flare to enhance the brightness of the planet relative to the star, as also suggested independently 1 by Argyle (1974) and Bromley (1992). For example, Proxima Cen, Figs.…”

Section: Introductionmentioning

confidence: 99%

“…Although flares may put strong constraints on habitability, those same, frequent, strong flares, provide an opportunity to enhance the detectability of light from the planet. The rapid variations during flares make the planet easier to detect in the immediate aftermath of the flare, potentially in directly reflected light (Argyle 1974;Bromley 1992), or resonance scattering (Bourrier et al 2017b), but also exploiting the possibility of a multitude of H2 fluorescence lines pumped by Lyα or FUV continuum, and neutral oxygen fluorescence (1302 Å, 1034 Å, 1306 Å) by Lyβ. The overall battering of the atmosphere by the flaring spectrum from the far ultraviolet (FUV) to X-rays could lead to UV emission through recombination of ionized species such as C II 1334.53 and 1335.71 (France et al 2010), or enhanced airglow phenomena throughout the electromagnetic spectrum.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The Direct Detection and Characterization of M-dwarf Planets Using Light Echoes

Sparks

White

Lupu

et al. 2018

ApJ

View full text Add to dashboard Cite

Exoplanets orbiting M dwarf stars are a prime target in the search for life in the Universe. M dwarf stars are active, with powerful flares that could adversely impact prospects for life, though there are counter-arguments. Here, we turn flaring to advantage and describe ways in which it can be used to enhance the detectability of planets, in the absence of transits or a coronagraph, significantly expanding the accessible discovery and characterization space. Flares produce brief bursts of intense luminosity, after which the star dims. Due to the light travel time between the star and planet, the planet receives the high intensity pulse, which it re-emits through scattering (a light echo) or intrinsic emission when the star is much fainter, thereby increasing the planet's detectability. The planet's light echo emission can potentially be discriminated from that of the host star by means of a time delay, Doppler shift, spatial shift, and polarization, each of which can improve the contrast of the planet to the star. Scattered light can reveal the albedo spectrum of the planet to within a size scale factor, and is likely to be polarized. Intrinsic emission mechanisms include fluorescent pumping of multiple molecular hydrogen and neutral oxygen lines by intense Lyα and Lyβ flare emission, recombination radiation of ionized and photodissociated species, and atmospheric processes such as terrestrial upper atmosphere airglow and near infrared hydroxyl emission. We discuss the feasibility of detecting light echoes and find that under favorable circumstances, echo detection is possible.

show abstract

Section: (6) Putting It All Togethermentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The Direct Detection and Characterization of M-dwarf Planets Using Light Echoes

Sparks

White

Lupu

et al. 2018

ApJ

View full text Add to dashboard Cite

show abstract

“…The influence of echoes on the light curves of Type II supernovae (SNe) has been discussed by, e.g., Di Carlo et al (2002), Roscherr & Schaefer (2000), Filippenko et al (1995), Chugai (1992), and Mackey (1987). The detection of echoes has been investigated around SNe (Wright 1980;Chevalier 1986;Schaefer 1987aSchaefer , 1987bEmmering & Chevalier 1989;Sparks 1994;Maslov 2000), novae (Gehrz 1988), and flaring stars (Argyle 1974;Bromley 1992;Gaidos 1994).…”

Section: Introductionmentioning

confidence: 99%

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

Sugerman

2003

Astron J

View full text Add to dashboard Cite

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.

show abstract

“…), the planet presents, by illumination, the same modulations with a delay DT and a relative amplitude R 2 /a 2 . An autocorrelation study of the star light curve could reveal this echo [3]. 4.…”

Section: The Observables In Each Detection Methodmentioning

confidence: 95%

Strategies for the Search of Life in the Universe

Schneider

1996

Chemical Evolution: Physics of the Origin and Evolution of Life

View full text Add to dashboard Cite

On the observability of extrasolar planetary systems

Cited by 8 publications

References 1 publication

The Direct Detection and Characterization of M-dwarf Planets Using Light Echoes

The Direct Detection and Characterization of M-dwarf Planets Using Light Echoes

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

Strategies for the Search of Life in the Universe

Contact Info

Product

Resources

About