CDROM/AJ/V106/P1533 NGC 2287 (Harris+ 1993) ================================================================================ NGC 2287: An Important Intermediate-Age Open Cluster Gretchen L. H. Harris, M. Pim Vatter Fitzgerald, Sanju Mehta, & B. Cameron Reed <1993, AJ, 106, 1533> =1993AJ....106.1533H ================================================================================ Abstract: We have obtained photoelectric UBV photometry for 100 stars, uvbyBeta photometry for 39 stars and MK spectral types for 80 stars in the field of NGC 2287. After combination with data from other sources, several interesting cluster properties are apparent. Both the UBV and uvbyBeta photometry point to a small but _nonzero_ reddening, while our spectral types confirm previous results indicating a high binary frequency for the cluster. Based on our spectral and photometric data for the cluster members with -1 <~ M(V) <~ 3 we find a _minimum_ binary frequency of 40% and discuss the possibility that the results may imply a binary frequency closer to 80%. The cluster age is found to be ~2x10^8 yr based on _both_ the main-sequence turnoff and the red giant distribution; the width of the turnup region can probably be explained by a combination of duplicity and a range in stellar rotation. File Summary: -------------------------------------------------------------------------------- File Name Lrecl Records Explanations -------------------------------------------------------------------------------- table1.dat 150 239 UBV photometry in NGC 2287 table1a.tex 115 1444 TeX version of left half of Table 1 table1b.tex 86 1445 TeX version of right half of Table 1 table2.dat 102 59 uvbyBeta photometry in NGC 2287 table2.tex 145 267 TeX version of Table 2 table4.dat 88 138 MK spectral types in NGC 2287 table4.tex 71 545 TeX version of Table 4 macros.tex 80 366 TeX macros for gernerating tables -------------------------------------------------------------------------------- Comments for file: table1.dat -------------------------------------------------------------------------------- Table 1 presents a unified set of UBV photometry from a number of different sources that was formed using a program by Peter Stetson. Details are given in section 2 of the printed paper. -------------------------------------------------------------------------------- Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 A5 --- HFMR Identification number as in the printed paper 6- 7 2X --- --- Blank 8 A1 --- A *Adopted cluster membership 9 1X --- --- Always '.' 10 A1 --- E *Excess membership indicator 11 A1 --- S *Spectrum membership indicator 12 A1 --- L *Luminosity membership indicator 13 A1 --- Z *ZAMS+CMD membership indicator 14-15 2X --- --- Blank 16-25 A10 --- Name *Identification numbers from other authors 26-31 F6.3 mag V Mean V magnitude 32 1X --- --- Blank 33 A1 --- v_V [V] Variability flag 34-36 F3.0 10-3mag e_V *Error of mean V magnitude 37-43 F7.3 mag B-V []? Mean (B-V) color 44-47 F4.0 10-3mag e_B-V []? Error of mean (B-V) color 48-54 F7.3 mag U-B []? Mean (U-B) color 55-58 F4.0 10-3mag e_U-B []? Error of mean (U-B) color 59-60 2X --- --- Blank 61-64 F4.2 --- PtmSp Spectral type derived from photometric data 65 A1 --- u_PtmSp Uncertainty in PtmSp 66-69 F4.1 --- LC Luminosity class from photometric data 70 A1 --- u_LC Uncertainty in LC 71 1X --- --- Blank 72-73 A2 --- o_H *No. of obs., this paper 74-75 A2 --- o_F *No. of obs., Feinstein et al., (1978) 76-77 A2 --- o_C *No. of obs., Cox (1954) 78-79 A2 --- o_E *No. of obs., Eggen (1974) 80-81 A2 --- o_He *No. of obs., Hoag et al. (1961) (photoelect.) 82-83 A2 --- o_Hg *No. of obs., Hoag et al. (1961) (photograph.) 84-85 A2 --- o_I *No. of obs., Ianna et al. (1987) 86-87 2X --- --- Blank 88-102 A15 --- Sp MK class; "()", indicates from other sources 103-110 F8.3 mag V0 Intrinsic V(0) magnitude derived by WATREDAO 111 A1 --- u_V0 Uncertainty in V0 112-115 F4.0 10-3mag e_V0 Error of V0 116 A1 --- u_e_V0 Uncertainty in e_V0 117-123 F7.3 mag B-V0 Intrinsic (B-V)(0) color derived by WATREDAO 124 A1 --- u_B-V0 Uncertainty in B-V0 125-128 F4.0 10-3mag e_B-V0 Error of B-V0 129 A1 --- u_e_B-V0 Uncertainty in e_B-V0 130-136 F7.3 mag V0-MV []? (V(0)-M(V)), assumes star lies on ZAMS 137-141 F5.0 10-3mag e_V0-MV []? Error of V0-MV 142 1X --- --- Blank 143-150 A8 --- Notes *Notes -------------------------------------------------------------------------------- Notes for file: table1.dat -------------------------------------------------------------------------------- A,E,S,L,Z: A - Adopted cluster membership, based on overall indicators E - Excess membership indicator based on consistency relation to the main sequence S - Spectrum membership indicator based on agreement of photometric and spectroscopic type L - Luminosity membership indicator based on agreement of photometric and spectroscopic class Z - ZAMS+CMD membership indicator based on position in color-magnitude diagram, especially for near-ZAMS (Zero-Age Main-Sequence) stars Codes for cluster membership indicators are as follows: B Probable binary member of cluster. b Possible binary member of cluster. C Possibly C+E. E Probably evolved. G Probable member of background group. g Possible member of background group. F Probable field object. f Possible field object. N Non-member of cluster or background group. n Possible non-member of cluster or background group. M Probable cluster member. m Possible cluster member. u No U B but photometry consistent with membership at mean cluster extinction. x Non-member due to incorrect color excess. Name: Identification numbers from other authors, Cox (1954, ApJ, 119, 188), Hoag et al. (1961, Pub. U.S. Naval Obs., 17, 349), or Ianna et al. (1987, AJ, 93, 347, AJ, 93, 347) e_V: Error of mean V magnitude. Errors reported in this table are based on observational error and estimates from other authors. For derived quantities the errors are those propagated through the photometric dereddening process. o_H, o_F, o_C, o_E, o_He, o_Hg, o_I: References: H this paper F Feinstein et al., (1978, A&AS, 43, 241) C Cox (1954, ApJ, 119, 188) E Eggen (1974, ApJ, 188, 59) He Hoag et al. (1961, Pub. U.S. Naval Obs., 17, 349) (photoelectric) Hg Hoag et al. (1961, Pub. U.S. Naval Obs., 17, 349) (photographic) I Ianna et al. (1987, AJ, 93, 347) Notes: A Near A hump in two color diagram; color excess could be too large. H Near F hump in two color diagram; color excess could be too large or small. 1 Smallest color excess chosen. 2 Second smallest color excess chosen. 3 Possibly contaminated by a nearby object. 4 Duplicity indicated by some MK classifications. 5 MK adopted is not from this study and is shown in brackets. 6 Binary; 0.5 to 0.8 magnitudes and more than 2 sigma above ZAMS. 7 Colors and spectrum incompatible. 8 Photometric spectrum and colors may be uncertain for bright giants. 9 Color excess chosen to suit membership and/or mean color excess. 10 Color excess more than 1 sigma from the mean. 12 Bad U B? 13 Deconvolved binary star. 15 Luminosity class incompatible with membership. 16 Color excess too high for membership,but star not necessarily excluded. 17 Outside cluster radius suggested by star counts. 18 Luminosity class supports duplicity. 19 6, 11, and 12. 20 7, 10, and 14. 21 Quoted photometry is from Ianna, Adler and Faudree. 22 U B from Ianna et al. 23 10, 16, 17, and 21. 24 10, 17, and 21. -------------------------------------------------------------------------------- Comments for file: table2.dat -------------------------------------------------------------------------------- Table 2 presents the results of uvbyBeta observations made by Fitzgerald in 1982 January-February with the University of Toronto Southern Observatory (UTSO) 0.6 m telescope and photon counting photometer combination. Details are given in section 2 of the printed paper. -------------------------------------------------------------------------------- Byte-by-byte Description of file: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 A5 --- HFMR Identification number as in the printed paper 6- 7 2X --- --- Blank 8-13 F6.3 mag V Mean V magnitude 14-16 F3.0 10-3mag e_V Error of mean V magnitude 17-23 F7.3 mag b-y Mean (b-y) color 24-26 F3.0 10-3mag e_b-y Error of mean (b-y) color 27-33 F7.3 mag m1 Mean m(1) index 34-36 F3.0 10-3mag e_m1 Error of mean m(1) index 37-43 F7.3 mag c1 Mean c(1) index 44-46 F3.0 10-3mag e_c1 Error of mean c(1) index 47-52 F6.3 mag Beta Mean Beta 53-55 F3.0 10-3mag e_Beta Error of mean Beta 56 1X --- --- Blank 57-58 A2 --- HF Photometry from this paper 59-60 A2 --- E1 Photometry from Eggen (1974, ApJ, 188, 59) 61-62 A2 --- E2 Photometry from Eggen (1981, ApJ, 247, 507) 63-64 2X --- --- Blank 65-66 A2 --- Meth *Method to derive values of E_b-y and V0-MV 67-73 F7.3 --- E_b-y []? E(b-y) 74-81 F8.3 mag V0 []? V(0) 82-89 F8.3 mag MV []? M(V) 90-95 F6.2 mag V0-MV []? V(0) - M(V) 96-97 2X --- --- Blank 98-99 A2 --- Memb1 *Membership from uvbyBeta photometry V0-MV 100 1X --- --- Blank 101-102 A2 --- Memb2 *Membership from UBV analysis of Table 1 -------------------------------------------------------------------------------- Notes for file: table2.dat -------------------------------------------------------------------------------- Meth: Code for method used to derive individual values of E(b-y) and V(0)-M(V): A Crawford (1979, AJ, 84, 1858, AJ, 84, 1858) A0 Claria (1974, Elementos de Fotometria Estellar, Instituto Venezolano de Astronomia (Merida, Venezuela)) adapted from Stromgren (1966, ARA&A, 4, 433) as described by Eggen (1981, ApJ, 247, 507) B Crawford (1978, AJ, 83, 48) F Crawford (1975, AJ, 80, 955) Memb1, Memb2: Codes for cluster membership indicators are as follows: B Probable binary member of cluster. b Possible binary member of cluster. C Possibly C+E. E Probably evolved. G Probable member of background group. g Possible member of background group. F Probable field object. f Possible field object. N Non-member of cluster or background group. n Possible non-member of cluster or background group. M Probable cluster member. m Possible cluster member. u No U B but photometry consistent with membership at mean cluster extinction. x Non-member due to incorrect color excess. -------------------------------------------------------------------------------- Comments for file: table4.dat -------------------------------------------------------------------------------- Given the large number of stars with peculiar characteristics, this table includes comments on the individual spectra along with spectral types from other sources. -------------------------------------------------------------------------------- Byte-by-byte Description of file: table4.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 5 A5 --- HFMR *Identification number as in the printed paper 6-21 A16 --- MK_adopt *Adopted MK type 22-43 A22 --- MK_plate *MK type from a single plate 44-51 A8 --- Date Date of observation (mm-dd-yy) 52 1X --- --- Blank 53-55 A3 --- Rem *Remarks 56-57 2X --- --- Blank 58-81 A14 --- MK_other *Other MK type 82 1X --- --- Blank 83-88 A6 --- Ref *Reference -------------------------------------------------------------------------------- Notes for file: table4.dat -------------------------------------------------------------------------------- HFMR: If this field is blank, the remainder of the fields are a continuation from the previous record MK_adopt, MK_plate, MK_other: Notations on Spectral Types: ? uncertain or conflicting criteria; : poor plate; / either range possible or between types given; - between types given; sV spectrum variable; SB2 H lines stronger than standards, broad and strong cores, atypical profiles (see LM). Rem: Key to Remarks A. Possible contamination from 1A. B. Poor standards at luminosity class III. C. Possible peculiar Hgamma. D. Hbeta,gamma lines show sharp core, diffuse wings. E. SB2? F. H lines broad; not n? G. H line wings slightly peculiar, luminosity difficult to determine. H. Very poor spectrum, moon contamination? Am? I. possible rotational broadening? sV? J. H lines ~ A0; weak G band, metal lines. K. Ca very strong; H lines peculiar. L. Could be III; very poor spectrum. M. H profiles square -> SB2? N. Poor luminosity standards; adopted LM type. O. H lines diffuse but no sharp core. P. Could be double not rotation. Q. H lines sharp; He4026 present. R. H lines broad; weak CaK, no He4026. S. Spectra for this star definitely different from each other. T. Hgamma,delta peculiar? U. Luminosity difficult to determine. V. Hgamma,delta double, CaK broad. W. Both CaK and He4026 present. X. Possible Ap or composite. Y. Hbeta,epsilon suggest n? Z. Possible composite? a. Possible weak Si4128. b. Standards poor; definitely more luminous than IIIb. c. Possible He4026? d. Possible square profiles. e. Either composite or shell. f. Spectra slightly different. g. A star appears stronger in 1981 exposure. h. Adopted LM type. i. He weak? j. CaK sharper than H lines? k. Hint of TiII 3993? Ref: Reference. The notation "[2]" indicates the spectral type is for both stars in the pair. Reference codes are listed below: C Cox, A. N. 1954, ApJ, 119, 188 H Hartoog, M. R. 1976, AJ, 205, 807 LG Levato, H., & Garcia, B. 1984, ApJ, 24, L161 LM Levato, H., & Malaroda, S. 1979, PASP, 91, 636 RHH van Rensbergen, W., Hammerschlag-Hensberge, G., & van den Heuvel, E. P. J. 1978, A&A, 64, 131 S Sowell, J. R. 1987, ApJS, 64, 241 -------------------------------------------------------------------------------- ================================================================================ (End) Lee Brotzman [ADS] 18-Mar-1995