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تسجيل مستخدم جديدDirect Imaging of Irregular Satellite Disks in Scattered Light
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Direct imaging surveys have found that long-period super-Jupiters are rare. By contrast, recent modeling of the widespread gaps in protoplanetary disks revealed by ALMA suggests an abundant population of smaller Neptune to Jupiter-mass planets at large separations. The thermal emission from such lower-mass planets is negligible at optical and near-infrared wavelengths, leaving only their weak signals in reflected light. Planets do not scatter enough light at these large orbital distances, but there is a natural way to enhance their reflecting area. Each of the four giant planets in our solar system hosts swarms of dozens of irregular satellites, gravitationally captured planetesimals that fill their host planets spheres of gravitational influence. What we see of them today are the leftovers of an intense collisional evolution. At early times, they would have generated bright circumplanetary debris disks. We investigate the properties and detectability of such irregular satellite disks (ISDs) following models for their collisional evolution from Kennedy and Wyatt 2011. We find that ISD brightnesses peak in the $10-100$ AU range probed by ALMA, and can render planets detectable over a wide range of parameters with upcoming high-contrast instrumentation. We argue that future instruments with wide fields of view could simultaneously characterize the atmospheres of known close-in planets, and reveal the population of long-period $sim$ Neptune-Jupiter mass exoplanets inaccessible to other detection methods. This provides a complementary and compelling science case that would elucidate the early lives of planetary systems.
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High-contrast scattered light observations have revealed the surface morphology of several dozens of protoplanetary disks at optical and near-infrared wavelengths. Inclined disks offer the opportunity to measure part of the phase function of the dust
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Debris disks around young main-sequence stars often have gaps and cavities which for a long time have been interpreted as possibly being caused by planets. In recent years, several giant planet discoveries have been made in systems hosting disks of p
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We present the first scattered-light images of two debris disks around the F8 star HD 104860 and the F0V star HD 192758, respectively $sim45$ and $sim67$ pc away. We detected these systems in the F110W and F160W filters through our re-analysis of arc
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