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J/MNRAS/352/285    u(bj)r & BV photometry of blue HB stars      (Clewley+, 2004)

Distant field blue horizontal branch stars and the mass of the Galaxy - II. Photometry and spectroscopy of UKST candidates 16<B<19.5, 11<R<52kpc Clewley L., Warren S.J., Hewett P.C., Norris J.E., Evans N.W. <Mon. Not. R. Astron. Soc., 352, 285-298 (2004)> =2004MNRAS.352..285C
ADC_Keywords: Stars, horizontal branch ; Blue objects ; Photometry, CCD ; Photometry, UBV ; Radial velocities ; Stars, distances Keywords: stars: horizontal branch - Galaxy: halo Abstract: This is the second in a series of papers presenting a new calculation of the mass of the Galaxy based on radial velocities and distances for a sample of faint 16<B<21.3 field blue horizontal-branch (BHB) stars. We present accurate BV CCD photometry and spectra for 142 candidate A-type stars selected from ubjr photometry of UK Schmidt telescope plates in six high-Galactic-latitude fields. Classification of these candidates produces a sample of 60 BHB stars at distances of 11-52kpc from the Sun (mean 28kpc), with heliocentric line-of-sight velocities accurate to 15km/s, and distance errors <10 per cent. We provide a summary table listing coordinates and velocities of these stars. Description: To achieve a higher degree of photometric accuracy, BV CCD observations were made of candidate BHB stars drawn from Table 4. We made a total of 421 observations of 280 stars over 47 photometric nights during the period 1998 to 2001. We obtained medium-resolution optical spectra of 156 survey stars over a total of 21 clear nights at the 4.2-m William Herschel Telescope (WHT), La Palma, and the 3.9-m Anglo-Australian Telescope (AAT), Siding Spring Observatory, Australia. Regions: ---------------------------------------------- RA (2000) DE Designation(s) (l , b) ---------------------------------------------- 0 55 -27 47 SGP 250 -89 2 53 0 12 SA94 175 -50 3 38 -34 50 F358 236 -54 10 23 -00 15 F854 244 45 12 43 -05 16 F789 299 58 22 06 -18 39 MT 37 -51 ---------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 64 461 Photometric catalogue of A-type stars selected from six UKST fields table7.dat 68 280 Photometric data for the blue horizontal-branch star candidates, corrected for extinction table11.dat 88 142 Spectroscopic data for the horizontal-branch star candidates
See also: J/A+AS/109/171 : Blue horizontal branch stars catalog (Flynn+, 1995) J/AJ/108/1722 : Blue horizontal branch stars (Kinman+ 1994) J/AJ/127/899 : Blue HB stars in SDSS (Sirko+, 2004) Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 9 A9 --- [CWH2004] Name 11- 12 I2 h RAh Right ascension (J2000.0) 14- 15 I2 min RAm Right ascension (J2000.0) 17- 21 F5.2 s RAs Right ascension (J2000.0) 23 A1 --- DE- Declination sign (J2000.0) 24- 25 I2 deg DEd Declination (J2000.0) 27- 28 I2 arcmin DEm Declination (J2000.0) 30- 34 F5.2 arcsec DEs Declination (J2000.0) 36- 40 F5.2 mag bjmag bj magnitude (1) 42- 46 F5.2 mag u-bj u-bj colour index (1) 48- 52 F5.2 mag bj-or bj-or colour index (1) 54- 57 F4.2 mag e_u-bj rms uncertainty on u-bj 59- 62 F4.2 mag e_bj-or rms uncertainty on bj-or
Note (1): UKST filters: --------------------------------------------------------- Name Wavelength (nm) at transmittances of 1/10 and 9/10 maximum values --------------------------------------------------------- bj : GG395 365 415 u : UG1 315,390 330,375 or : OG590 580 600 ---------------------------------------------------------
Byte-by-byte Description of file: table7.dat
Bytes Format Units Label Explanations
1- 9 A9 --- [CWH2004] Name (1) 10 A1 --- m_[CWH2004] [qv] Multiplicity index on [CWH2004] 12- 13 I2 h RAh Right ascension (J2000.0) 15- 16 I2 min RAm Right ascension (J2000.0) 18- 22 F5.2 s RAs Right ascension (J2000.0) 24 A1 --- DE- Declination sign (J2000.0) 25- 26 I2 deg DEd Declination (J2000.0) 28- 29 I2 arcmin DEm Declination (J2000.0) 31- 35 F5.2 arcsec DEs Declination (J2000.0) 37- 41 F5.2 mag Vmag V magnitude 43- 47 F5.2 mag (B-V)0 Dereddend B-V colour index 49- 53 F5.3 mag e_Vmag rms uncertainty on Vmag 55- 59 F5.3 mag e_(B-V)0 rms uncertainty on (B-V)0 61- 65 F5.3 mag E(B-V) Reddening in B-V 67 I1 --- N Number of photometric nights (2)
Note (1): Suspected variables are labelled 'V'. Stars that were subsequently found to be quasars are labelled 'q'. Stars in the complete sample have names prefixed 'C', otherwise the stars are prefixed 'I'. Note (2): The dates and total number of photometric nights 'N' for the photometric survey in each of the six fields presented in Table 1. Observations were made using the 1.0-m Jacobus Kapteyn Telescope (JKT), the 2.5-m Isaac Newton Telescope (INT) and the 2.3-m Telescope at Siding Spring Observatories (SSO). ---------------------------------------------------------------------- Telescope Date N Fields ----------------------------------------------------------------------- SSO 1998 Sep 13-16 4 SGP JKT 1998 Oct 15, 17-20 5 SA94, MTF SSO 1999 Mar 12-18 7 F854, F789, SGP JKT 1999 April 4, 7-9 4 F854, F789 SSO 1999 Oct 11-17 7 SGP JKT 1999 Oct 30-31, Sep 1, 3-5 6 SA94, MTF SSO 1999 Nov 17-20 4 F358 SSO 2000 Feb 24 4 F854, F789 JKT 2000 Mar 23, 26, 28 3 F854, F789 INT 2001 Mar 29-30, Apr 1 3 SA94, MTF
Byte-by-byte Description of file: table11.dat
Bytes Format Units Label Explanations
1- 9 A9 --- [CWH2004] Name 10 A1 --- n_[CWH2004] [Nbv] Multiplicity index on [CWH2004] 12- 16 F5.2 0.1nm D0.15(gd) D0.15 parameter (1) 18- 21 F4.2 0.1nm e_D0.15(gd) rms uncertainty on D0.15 23- 27 F5.2 0.1nm b(gd) b parameter (1) 29- 32 F4.2 0.1nm c(gd) c parameter (1) 34- 38 F5.2 0.1nm A Semi-major axes of the error ellipse in the b-c plane (2) 40- 44 F5.3 0.1nm B Semi-minor axes of the error ellipse in the b-c plane (2) 46- 50 F5.3 rad theta Orientation of the semi-major axis measured anti-clockwise from the b-axis (2) 52- 55 F4.1 [Sun] [Fe/H] ? Measured metallicity 57- 59 F3.1 [Sun] e_[Fe/H] ? rms uncertainty on [Fe/H] 61- 67 F7.2 km/s HRV Heliocentric radial velocity 69- 72 F4.1 km/s e_HRV rms uncertainty on HRV 74- 77 F4.1 kpc Dist Heliocentric distance 79- 81 F3.1 kpc e_Dist rms uncertainty on Dist 83- 87 A5 --- Class Classification as BHB (blue horizontal-branch) or A/BS (field blue straggler)
Note (1): Two methods were developed in paper I (Clemens et al., 2002MNRAS.337...87C) to separate the two populations of A stars. Both methods employ a Sersic function fit to the Hγ and Hδ absorption lines. -- The first method, the 'D0.15-colour' method, plots the average of the width of the two Balmer lines against (B-V)0 colour. -- The second method, called the scale-width-shape method, plots two parameters of the Sersic fit, the scale-width b, against the power-law exponent c. Note (2): The errors on the parameters b(gd) and c(gd) are provided with the A, B and theta parameters of the error ellipse.
Acknowledgements: Lee Clewley, clewley(at)astro.ox.ac.uk References: Clewley et al., Paper I 2002MNRAS.337...87C
(End) Patricia Vannier [CDS] 24-Feb-2005
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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