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Recently, analysis of near-infrared broad-band photometry and Spitzer IRS spectra has led to the identification of a new pre-transitional disk class whose members have an inner optically thick disk separated from an outer optically thick disk by an optically thin gap. This is in contrast to the transitional disks which have inner disk holes (i.e. large reductions of small dust from the star out to an outer optically thick wall). In LkCa 15, one of these proposed pre-transitional disks, detailed modeling showed that although the near-infrared fluxes could be understood in terms of optically thick material at the dust sublimation radius, an alternative model of emission from optically thin dust over a wide range of radii could explain the observations as well. To unveil the true nature of LkCa 15s inner disk we obtained a medium-resolution near-infrared spectrum spanning the wavelength range 2-5 microns using SpeX at the NASA Infrared Telescope Facility. We report that the excess near-infrared emission above the photosphere of LkCa 15 is a black-body continuum which can only be due to optically thick material in an inner disk around the star. When this confirmation of a primordial inner disk is combined with earlier observations of an inner edge to LkCa 15s outer disk it reveals a gapped structure. Forming planets emerge as the most likely mechanism for clearing the gap we detect in this evolving disk.
We present CARMA 1.3 mm continuum observations of the T Tauri star LkCa 15,which resolve the circumstellar dust continuum emission on angular scales between 0.2-3 arcsec, corresponding to 28-420 AU at the distance of the star. The observations resolv
We present Karl G. Jansky Very Large Array (VLA) observations of the 7 mm continuum emission from the disk surrounding the young star LkCa 15. The observations achieve an angular resolution of 70 mas and spatially resolve the circumstellar emission o
Exoplanet detections have revolutionized astronomy, offering new insights into solar system architecture and planet demographics. While nearly 1900 exoplanets have now been discovered and confirmed, none are still in the process of formation. Transit
Two studies utilizing sparse aperture masking (SAM) interferometry and $H_{rm alpha}$ differential imaging have reported multiple jovian companions around the young solar-mass star, LkCa 15 (LkCa 15 bcd): the first claimed direct detection of infant,
With the legacy of Spitzer and current advances in (sub)mm astronomy, a large number of transitional disks has been identified which are believed to contain gaps or have developped large inner holes, some filled with dust. This may indicate that comp