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J/AJ/117/1313       NGC 6441 VI photometry                   (Layden+, 1999)

The variable stars and blue horizontal branch of the metal-rich globular cluster NGC 6441. Layden A.C., Ritter L.A., Welch D.L., Webb T.M.A. <Astron. J. 117, 1313 (1999)> =1999AJ....117.1313L
ADC_Keywords: Clusters, globular ; Stars, variable ; Photometry Keywords: color-magnitude diagrams - globular clusters: individual (NGC 6441) - RR Lyrae variable - stars: horizontal-branch - stars: variables: general Abstract: We present time-series VI photometry of the metal-rich ([Fe/H]=-0.53) globular cluster NGC 6441. Our color-magnitude diagram shows that the extended blue horizontal branch seen in Hubble Space Telescope data exists in the outermost reaches of the cluster. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 17 50 12.8 -37 03 04 NGC 6441 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 46 16011 Photometry of 16011 stars with V<19.0 within 440 arcsec of NGC 6441 var.dat 72 57 Variable stars (tables 2-5 of paper) table6.dat 45 1391 Photometry of variable stars toward NGC 6441 notes.dat 80 65 Individual notes of var.dat
See also: V/97 : Updated 3rd Cat Variable Stars in Globular Clusters (Clement+ 1997) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 5 I5 --- LRW Star number (Cl* NGC 6441 LRW NNNNN in Simbad) 7- 13 F7.2 pix Xpos X position (G1) 15- 21 F7.2 pix Ypos Y position (G1) 23- 28 F6.3 mag Vmag V magnitude 30- 34 F5.3 mag e_Vmag rms uncertainty on Vmag 36- 40 F5.3 mag V-I V-I colour index 42- 46 F5.3 mag e_V-I rms uncertainty on V-I
Byte-by-byte Description of file: var.dat
Bytes Format Units Label Explanations
1- 3 A3 --- Star Star name (Cl* NGC 6441 Saw VNN in Simbad) 4 A1 --- Note [*] Individual note detailed in notes.dat 6- 7 A2 --- Type Type of variable (1) 9- 14 F6.4 d Period ? Period (for RR Lyr and EBs) 16- 19 I4 pix Xpos X position (G1) 21- 24 I4 pix Ypos Y position (G1) 26- 30 F5.2 mag Vmag ? V at maximum (EBs), or mean V (2) 32- 36 F5.2 mag Imag ? I at maximum (EBs), or mean I (2) 38- 42 F5.2 mag V-I ? (V-I) at minimum for EBs, mean (v-I) color 44- 48 F5.2 mag DV ? Amplitude in V filter 50- 54 F5.2 mag DI ? Amplitude in I filter 56- 57 I2 --- o_Imag ? Number of observations in Imag 59- 63 F5.2 mag Imag2 ? Mean Imag in June 1996 (for LP only) 65- 69 F5.2 mag (V-I)2 ? Mean (V-I) in June 1996 (for LP only) 71- 72 I2 --- o_Imag2 ? Number of observations in Imag2
Note (1): the type can be: LP: long-period variable (table 2) RR: RR Lyr star (table 3) EB: Eclipsing binaries (table 4) SV: Suspected variables (table 5) Note (2): The values represent the magnitude at maximum for eclipsing binaries (EB in column Type), and mean magnitudes for other types; for long period stars (LP), the mean corresponds to observations made in May 1996.
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 3 A3 --- Star Star name (V01-V49, SV1-SV9) (1) 4 A1 --- n_Star [*] *: Note detailed in notes.dat file 6- 17 F12.4 d HJD Heliocentric Julian date 19- 24 F6.3 mag Vmag V magnitude 26- 30 F5.3 mag e_Vmag rms uncertainty on Vmag 32- 37 F6.3 mag Imag I magnitude 39- 43 F5.3 mag e_Imag rms uncertainty on Imag 45 I1 --- q_Vmag [1,4] Quality parameter (2)
Note (1): variable and suspected variables are: VNN: Cl* NGC 6441 Saw VNN in Simbad SVN: Cl* NGC 6441 LRW SN in Simbad Note (2): the quality is coded as follows: 1: exposure under good seeing conditions 2: short exposure in good seeing 3: long exposure in poor seeing 4: short exposure in poor seeing
Byte-by-byte Description of file: notes.dat
Bytes Format Units Label Explanations
1- 3 A3 --- Star Star designation, repeated when several lines 5- 80 A76 --- Note Text of the note
Global Notes: Note (G1): North is down, and east is to the left. Pixel coordinates range from (X, Y) = (1, 1) at the lower left to (2048, 2048) at the upper right, with the cluster center lying at (1014, 1000). The right ascension and declination offsets from the cluster center (in arcseconds, with positive values indicating east and north) can be computed from the pixel positions as follows: ΔRA = -0.396(Xpos - 1014), ΔDE = -0.396(Ypos - 1000)
History: From AJ electronic version * 25-Apr-2000: the missing data for SV2 in table 5 (file var.dat) were kindly supplied by Andy Layden
(End) James Marcout, Patricia Bauer, Francois Ochsenbein [CDS] 04-Oct-1999
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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