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تسجيل مستخدم جديدNearby candidate dust-disk pre-main-sequence solar-mass stars
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A.A. Suchkov
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I have isolated a population of numerous F stars that appear to be pre-main-sequence (PMS). The candidate PMS stars have been identified using CM diagram, reddening, flux excess in the UV and near-infrared, and luminosity anomaly. Negative luminosity anomaly and excessive UV flux for many of these stars is suggestive of accretion disks, while the NIR excess is indicative in many cases of the presence of dust disk thermal emission. Observed overluminosity of many PMS candidates is consistent with their pre-main-sequence status. The bulk of the PMS candidates is located within 200 pc, exhibiting strong association with regions of star formation that are numerous between ~130 to 180 pc. The number of PMS candidates plummets redward of the spectral type ~ F5. This effect may provide important clues for understanding the evolution of PMS stars in the solar-mass range.
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