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J/AJ/114/699              Spectrophotometry in open clusters (Clampitt+ 1997)

Spectrophotometry of 237 stars in 7 open clusters Clampitt L., Burstein D. <Astron. J. 114, 699 (1997)> =1997AJ....114..699C
ADC_Keywords: Clusters, open ; Spectrophotometry ; Photometry, uvby Abstract: Spectrophotometry is presented for 237 stars in 7 nearby open clusters: Hyades, Pleiades, Alpha Persei, Praesepe, Coma Berenices, IC 4665, and M39. The observations were taken by Lee McDonald and David Burstein using the Wampler single-channel scanner on the Crossley 0.9m telescope at Lick Observatory from 1973 July through 1974 December. Sixteen bandpasses spanning the spectral range 3500-7780Å were observed for each star, with bandwidths 32, 48, or 64Å. Data are standardized to the Hayes-Latham system to mutual accuracy of 0.016mag per passband. The accuracy of the spectrophotometry is assessed in three ways on a star-by-star basis. First, comparisons are made with previously published spectrophotometry for 19 stars observed in common. Second, (B-V) colors and uvby colors are compared for 236 stars and 221 stars, respectively. Finally, comparisons are made for 200 main sequence stars to the spectral synthesis models of Kurucz, fixing logg=4.0 and [Fe/H]=0.0, and only varying effective temperature. The accuracy of tests using uvby colors and the Kurucz models are shown to track each other closely, yielding an accuracy estimate (1σ) of 0.01mag for the 13 colors formed from bandpasses longward of the Balmer jump, and 0.02mag for the 3 colors formed from the three bandpasses below the Balmer jump. In contrast, larger scatter is found relative to the previously published spectrophotometry of Bohm-Vitense & Johnson (1977ApJS...35..461B) (16 stars in common) and Gunn & Stryker (1983, Cat. III/88) (3 stars). We also show that the scatter in the fits of the spectrophotometric colors and the uvby filter colors is a reasonable way to identify the observations of which specific stars are accurate to 1σ, 2σ, .... As such, the residuals from both the filter color fits and the Kurucz model fits are tabulated for each star where it was possible to make a comparison, so users of these data can choose stars according to the accuracy of the data that is appropriate to their needs. The very good agreement between the models and these data verifies the accuracy of these data, and also verifies the usefulness of the Kurucz models to define spectrophotometry for stars in this temperature range (>5000K). These data define accurate spectrophotometry of bright, open cluster stars that can be used as a secondary flux calibration for CCD-based spectrophotometric surveys. (c) 1997 American Astronomical Society. Description: The final calibrated spectral energy distributions (SEDs; relative to 5556Å) for all 237 stars are given in Table 4 according to the cluster identification number, the star HD or BD number, and the night(s) of observation. Table 6 lists the observed B-V and uvby data as obtained from SIMBAD, together with the differences (observed minus predicted) between the colors predicted from the authors' spectrophotometry and the observed colors. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 126 237 Spectral Energy Distributions for 237 open cluster stars table6.dat 131 237 Star-by-star comparison to filter colors and Kurucz models
See also: I/68 : Positions & Proper Motions in alpha Per (Fresneau 1980) I/163 : US Naval Observatory Pleiades Catalog (Van Flandern 1969) J/MNRAS/257/257 : Proper motions in the Hyades (Reid 1992) III/55 : Radial Velocities in Open Clusters (Mermilliod 1979) II/194 : Photometric study of IC 4665 (McCarthy+ 1969) J/AJ/105/1441 : IC 4665 (Prosser 1993) I/203 : NGC 7092 region PM, UBV-phot and SpClass (Platais 1994) J/other/AcASn/32.176 : Stars of Praesepe (Wang+ 1991) Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 8 A8 --- ID Star identification number (1) 10- 14 A5 --- Night Nights observed (2) 17- 20 I4 mmag 3500 ?=9999 3500-5556 color (4) 21 A1 --- u_3500 [:*] indicates larger error in color (3) 24- 27 I4 mmag 3571 ?=9999 3571-5556 color (4) 28 A1 --- u_3571 [:*] indicates larger error in color (3) 31- 34 I4 mmag 3636 ?=9999 3636-5556 color (4) 35 A1 --- u_3636 [:*] indicates larger error in color (3) 38- 41 I4 mmag 4036 ?=9999 4036-5556 color (4) 42 A1 --- u_4036 [:*] indicates larger error in color (3) 45- 48 I4 mmag 4167 ?=9999 4167-5556 color (4) 49 A1 --- u_4167 [:*] indicates larger error in color (3) 52- 55 I4 mmag 4255 ?=9999 4255-5556 color (4) 56 A1 --- u_4255 [:*] indicates larger error in color (3) 59- 62 I4 mmag 4400 ?=9999 4400-5556 color (4) 63 A1 --- u_4400 [:*] indicates larger error in color (3) 66- 69 I4 mmag 4565 ?=9999 4565-5556 color (4) 70 A1 --- u_4565 [:*] indicates larger error in color (3) 73- 76 I4 mmag 4785 ?=9999 4785-5556 color (4) 77 A1 --- u_4785 [:*] indicates larger error in color (3) 80- 83 I4 mmag 5000 ?=9999 5000-5556 color (4) 84 A1 --- u_5000 [:*] indicates larger error in color (3) 87- 90 I4 mmag 5263 ?=9999 5263-5556 color (4) 91 A1 --- u_5263 [:*] indicates larger error in color (3) 94- 97 I4 mmag 5840 ?=9999 5840-5556 color (4) 98 A1 --- u_5840 [:*] indicates larger error in color (3) 101-104 I4 mmag 6300 ?=9999 6300-5556 color (4) 105 A1 --- u_6300 [:*] indicates larger error in color (3) 108-111 I4 mmag 6710 ?=9999 6710-5556 color (4) 112 A1 --- u_6710 [:*] indicates larger error in color (3) 115-118 I4 mmag 7100 ?=9999 7100-5556 color (4) 119 A1 --- u_7100 [:*] indicates larger error in color (3) 122-125 I4 mmag 7400 ?=9999 7400-5556 color (4) 126 A1 --- u_7400 [:*] indicates larger error in color (3)
Note (1): Number of star according to the following sources: Hyades (Hya): Van Bueren, 1952BAN....11..385V Pleiades (Ple): Hertzsprung, E., 1947AnLei..19a...1H alpha Per (Per): Heckmann, O. et al. 1956AN....283..109H Praesepe (Pra): Klein-Wassink, W. J., 1927PGro...41....1K Coma Berenices (Com): Trumpler, F. J., 1938LicOB..18..167T IC 4665 (IC4): Kopff, 1943AN....274...69K M39 (M39): Ebbinghausen, E. G., 1940ApJ....92..434E Note (2): Night of observation + secondary standard star(s) used for night 1 Jul 17/18, 1973 M39 M39 33 2 Aug 14/15, 1973 Pleiades Ple 785 3 Aug 15/16, 1973 M39,alpha Persei Per 605 4 Sep 15/16, 1973 Pleiades Ple 785 5 Sep 16/17, 1973 Hyades Hya 56 6 Sep 17/18, 1973 alpha Persei,Pleiades Ple 785 7 Sep 18/19, 1973 Pleiades Ple 785 8 Sep 20/21, 1973 Hyades Hya 56 9 Oct 12/13, 1973 Hyades Hya 56 10 Oct 13/14, 1973 Hyades Hya 56 11 Mar 8/ 9, 1974 Hyades,Praesepe,Coma B. Hya 56 12 Mar 9/10, 1974 Coma B. Com 60 13 Apr 10/11, 1974 Praesepe Pra 300 14 May 6/ 7, 1974 Coma B. Com 60 15 May 7/ 8, 1974 Praesepe,Coma B.,IC 4665 Pra 300,Com 60 16 Aug 9/10, 1974 IC 4665 IC4 62 17 Dec 29/30, 1974 Hyades,Pleiades,alpha Persei Hya 56 stan If star is used as secondary standard for that cluster Note (3): Indicator if error of observation known to be larger than typical error : = error of 0.03-0.06 mag; * = interpolated value from star color and bracketing observations. Note (4): Spectrophotometric colors of the cited filter formed with the 5556 filter (15 colors). All colors are expressed in terms of 0.0001 magnitudes (e.g., a value of 1225 is a color of 1.225mag).
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 8 A8 --- ID Star identification number (1) 10- 15 I6 --- HD ? HD number of star 17- 18 I2 h RAh Right Ascension 1950 from SIMBAD 19 A1 --- --- Always ':' 20- 21 I2 min RAm Right Ascension 1950 from SIMBAD 22 A1 --- --- Always ':' 23- 26 F4.1 s RAs Right Ascension 1950 from SIMBAD 27 A1 --- DE- Declination sign 28- 29 I2 deg DEd Declination 1950 from SIMBAD 30 A1 --- --- Always ':' 31- 32 I2 arcmin DEm Declination 1950 from SIMBAD 33 A1 --- --- Always ':' 34- 37 F4.1 arcsec DEs Declination 1950 from SIMBAD 39- 48 A10 --- Sp Spectral type from SIMBAD (2) 49 A1 --- Notes Notes for particular stars (3) 50- 54 F5.2 mag Vmag Apparent V mag from SIMBAD 56- 61 F6.3 mag B-V 9.999? Observed B-V color from SIMBAD 64- 68 F5.3 mag u-b 9.999? Observed u-b color from SIMBAD 71- 75 F5.3 mag v-y 9.999? Observed v-y color from SIMBAD 77- 82 F6.3 mag b-y 9.999? Observed b-y color from SIMBAD 85- 90 F6.3 mag dB-V 9.999? B-V color diff, US-SIMBAD (4) 92- 97 F6.3 mag du-b 9.999? u-b color diff, US-SIMBAD (4) 98 A1 --- n_du-b [:] Bad u-b color comparision (5) 99-104 F6.3 mag dv-y 9.999? v-y color diff, US-SIMBAD (4) 105 A1 --- n_dv-y [:] Bad v-y color comparision (5) 106-111 F6.3 mag db-y 9.999? b-y color diff, US-SIMBAD (4) 112 A1 --- n_db-y [:] Bad b-y color comparision (5) 113-118 F6.3 mag dkurbl 9.999? Kurucz comparison, blue col (6) 120-125 F6.3 mag dkurrd 9.999? Kurucz comparison, red col (6) 127-131 F5.2 mag Vabs Absolute V mag (7)
Note (1): Number of star according to the following sources: Hyades (Hya): Van Bueren, 1952BAN....11..385V Pleiades (Ple): Hertzsprung, E., 1947AnLei..19a...1H alpha Per (Per): Heckmann, O. et al. 1956AN....283..109H Praesepe (Pra): Klein-Wassink, W. J., 1927PGro...41....1K Coma Berenices (Com): Trumpler, F. J., 1938LicOB..18..167T IC 4665 (IC4): Kopff, 1943AN....274...69K M39 (M39): Ebbinghausen, E. G., 1940ApJ....92..434E Note (2): Spectral type from SIMBAD. A colon on either spectral class or luminosity class indicates uncertainty. Note (3): Data come from SIMBAD unless a note is given. The note code is: c: these stars are variable according to SIMBAD d: Luminosity class taken from Mendoza, E. E. 1967BOTT....4..149M e: Spectral class taken from Crawford & Barnes 1972AJ.....77..862C f: Luminosity class taken from Crawford & Barnes, 1972AJ.....77..862C Note (4): The residuals from comparing the spectrophotometric colors with B-V, u-b, v-y, b-y colors from SIMBAD. The color transformations are as follows: Color Transformation Slope Z.P. error Johnson B-V Matthews & Sandage 1.072 0.433 0.021 (1963ApJ...138...30M) Stromgren u-b 3500 - (4565+4785)/2 1.005 0.125 0.024 Stromgren b-y (4565+4785)/2 0.934 0.153 0.013 Stromgren v-y (4036+4167)/2 0.891 0.415 0.032 The color transformation for B-V was done using the airmass = 1 bandpass functions for B and V mag as given by Matthews & Sandage Note (5): If indicated by a colon (:), this color comparison was not used in determining the color transformations. Note (6): These are the average residuals from the best fit of Kurucz main sequence model spectral energy distributions to the main sequence stars in our sample. dkurbl are the residuals for the three colors with one passband falling below 4000 angstroms. dkurrd are the residuals for the 12 colors with both passbands falling at or above 4000 angstroms. Note that the residuals from the Kurucz fit (dkurbl and dkurrd) are well-correlated with the residuals from the uvby fits (dkurbl with du-b; dkurrd with db-y), so that the size of the color residuals is a good indication of the error of spectrophotometric observation, as detailed in the paper. Note (7): The absolute V magnitude, extinction corrected, according to the following values for reddening and distances: dist(pc) E(B-V) Praesepe 180 0.03 Hyades 43 0.00 Coma Berenices 90 0.00 M39 290 0.06 Pleiades 180 0.06 IC 4665 470 0.17 alpha Persei 230 0.10 The distances are estimated by a direct fit of the ZAMS line from Mihalas & Binney (1981, Galactic Astronomy (Freeman, New York) p. 106) to the V vs. B-V diagrams as published in our paper. The reddenings come from the 5th edition of the Lund-Strasbourg Catalog (Lynga 1987, Cat. VII/92)
Origin: AAS CD-ROM series, Volume 9, 1997ASU] Oct-01-1997
(End) [CDS] 05-Feb-1998
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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