UBV (RI)c observations of Johnson's standard sequence in IC 4665. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996MNRAS.282..313M&db_key=AST
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V728 Herculis - an active W Ursae Majoris system of F spectral type Observations made of the short-period eclipsing binary system V728 Herusing a photoelectric telescope on four nights in June 1988 at LowellObservatory are presented. Three times of minimum light were revealed byobservations covering the eclipse portions of the light curves. A periodstudy covering 80 years of observations indicates that a drastic periodincrease may have recently occurred, while indications such as apossible reversal of eclipse depths may suggest that V728 Her ismagnetically active. Standard magnitudes derived for V728 Her and forcomparison and check stars indicate that V728 Her is approximately ofspectral type F3 while the comparison and check stars are K type. Apreliminary light-curve solution indicates that the system consists oftwo nearly equal temperature components in the spectral class F3 to F4in contact with a substantial fillout of near 20 percent and a massratio of about 0.4. This degree of contact is supported by the positionof V728 Her on the period, color plane of Eggen. The period increase mayindicate a mass exchange from the secondary to the primary component ora catastrophic angular-momentum loss due to an episode of massivestellar wind expulsion along lines of a corotating magnetic field.
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Membership of the open cluster IC 4665. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&A....17..193S&db_key=AST
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A photometric study of the open cluster IC 4665 Not Available
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Positions and proper motions of stars in the region of the galactic cluster IC 4665. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955AJ.....60..384V&db_key=AST
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The Standard Region Near IC 4665. Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1954ApJ...119..181J&db_key=AST
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Untersuchung der offenen Sternhaufen IC 4665, NGC 6633, IC 4756 Not Available
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