COMMISSION 27 OF THE I. A. U. INFORMATION BULLETIN ON VARIABLE STARS Number 2550 Konkoly Observatory Budapest 11 July 1984 HU ISSN 0374-0676 SPECTRAL TYPES OF ECLIPSING BINARIES IN OPTICAL COINCIDENCE WITH CLUSTERS AND ASSOCIATIONS 18 eclipsing binaries which have been listed by Sahade and Davila (1963) as being in optical coincidence with known clusters and associations were observed by the author utilizing the 2.1-m telescope and image-intensified White spectrograph of the Kitt Peak Observatory. 46 A/mm was achieved on forming gas baked IIIa-J plates in the second order blue. All plates were of good quality. The spectrum of each system was visually classified by comparison with the MK classes of known standard stars. Table I contains the Table I Spectral Types Variable UT Date SP Type. Previous Cluster SP Type. V447 Cyg 1983 Jul 17.324 F8 Ve (comp?) A3 + F5 NGC 6871 V586 Cyg 1982 Jun 27.406 A1 Ve -- NGC 7039 TZ Lac 1982 Jun 28.454 F8 III (wk G) -- NGC 7243 FP Mon 1983 Feb 2.335 F6 V (comp) -- NGC 2353 LL Oph 1982 Jun 27.218 G5 (II/III) comp -- Cr 302 QR Oph 1983 Jul 17.213 G8 V -- Cr 302 V378 Oph 1983 Jul 18.244 F8 V (comp?) -- Cr 359 V391 Oph 1983 Jul 18.260 A9 V A1, G5 Cr 359 V441 Oph 1982 Jun 26.161 B9 III/IV A0 Cr 302 V487 Oph 1982 Jun 28.230 F0 III -- Cr 359 CM Per 1983 Jul 16.465 A3 V -- Stock 2 CS Per 1983 Jul 16.481 G0 IV -- Stock 2 HS Per 1982 Jun 29.449 A0 II/III -- Stock 4 IM Sco 1983 Jul 17.190 G2 V -- Cr 302 V702 Sco 1983 Jul 17.240 A0 Ve B4 NGC 6383 BS Sct 1982 Jun 25.435 B7e B5, A0 III, A7 M11 FN Sct 1982 Jun 25.307 B3 Ve -- NGC 6704 BU Ser 1983 Jul 16.309 A0 V -- IC 4756 spectral types and plate information. The previous spectral type listed is usually from the GCVS. Individual comments for some of the stars follow. V447 Cyg: There is a single emission peak at H beta, but no emission at H gamma. Possibly there exist faint emissions longward of H beta. The spectrum is veiled as if composite. TZ Lac: The G-band is visible, though suppressed for the spectral type. FP Mon: The spectrum is thought to show composite characteristics due to the weakness of the K-line and the unnatural suppression of H gamma. LL Oph: The entire spectrum is veiled, particularly towards the shorter wavelengths. The Balmer lines are quite weak and the CN break strong. V 378 Oph: A possible composite spectrum is indicated by the inordinate width of the Balmer Lines, a slight veiling, and a possibly double H delta. V702 Sco: There exists a single emission peak in the H beta line, but no emission elsewhere. BS Sct: There ere definite double emission fringes at lambda4471 of He I, but no emission at the Balmer lines. Faint double emissions (probably of Fe II) also appear to the violet of H gamma. According to Hall and Mallama (1974), there have been conflicting classifications for the primary star: F8, A7, and A0 III. Their photometric observations during primary eclipse gave a possible range for the primary of B5-A7. BS Sct is found to be a likely member of M11 as a consequence of its early spectral type and also a possible blue straggler. FN Sct: There exists strong double emission at the He I lines and other possible emissions of Fe II. No emission is seen at the Balmer lines. ELAINE M. HALBEDEL* Corralitos Observatory P.O. Box 16314 Las Cruces, NM 88004 U.S.A. *Visiting Astronomer, Kitt Peak Observatory, National Optical Astronomy Observatories, operated by the Association of Universities for Research in Astronomy, Inc., which is operated under contract with the National Science Foundation. References: Hall, D.S. and Mallama, A.D., 1974, Acta.Astr., 24, 359 [BIBCODE 1974AcA....24..359H ] Sahade, J. and Davila, F., 1963, Ann. d'Ap., 26,153 [BIBCODE 1963AnAp...26..153S ]