Photometric Sequences at Dec=-30°

All of these fields were observed using the 0.9m telescope at CTIO with a TeK2048×2048 CCD which has a 13' field of view. There are 14 fields with B and R magnitudes and a further 12 fields with UBVR photometry. The data was reduced using the IRAF image reduction package, a 10 pixel (4") radius aperture was used to minimize errors from the background in faint objects, these magnitudes were aperture corrected to a 25 pixel (10") radius using at least 8 of the brightest stars in each field to define the aperture correction. the size of this correction was typically 0.03 mag with an RMS scatter within each field of ~0.005 mag. It should be noted therefore that these magnitudes will only be accurate for objects with stellar PSFs. We have also included in the tables below photometry of all the objects using a 25 pixel aperture and a rough star galaxy separation parameter using the difference between 10 pixel and 6 pixel radius apertures in the B band. Any objects with magnitudes equal to 0.000 do not have magnitudes available in the particular band.

These are not highly accurate photometric standards and should not be used as such. The main purpose of the objects is to provide appropriate calibration for large area cosmological or graphical surveys (e.g. photographic surveys or new panoramic CCD surveys). The data is available with RA, Dec (J2000), magnitudes and errors for both the BR and UBVR sequences.

Catalogue Changes 21/2/99

I have made some changes to the catalogues, so that they are consistent with the published paper. The magnitudes are now only quoted to 2 decimal places, and I have only included objects which have B mag errors less than or equal to 0.05 mag. Errors are not quoted for objects with errors <0.01 mag, as these will be dominated by systematic errors from the photometric fits and other sources.

BR Sequences

These sequences were observed on 23-28 August 1995 by Andrew Ratcliffe and Quentin Parker. RA and Dec for the field centres are shown next to the field names. Each file has the following format:

object name, RA(J2000) hh mm ss.ss, Dec(J2000) dd mm ss.s, B mag, B error, B(25) mag, s/g, R mag, R error, R(25) mag

  1. f409-1 RA: 00 01 12.78 Dec: -27 33 48.6
  2. f410-1 RA: 00 36 43.89 Dec: -29 31 34.5
  3. f411-1 RA: 00 51 19.84 Dec: -28 30 20.4
  4. f412-1 RA: 01 16 48.89 Dec: -28 35 06.6
  5. f413-1 RA: 01 34 23.38 Dec: -31 38 30.4
  6. f414-1 RA: 02 06 33.93 Dec: -28 18 41.0
  7. f415-1 RA: 02 20 47.83 Dec: -31 54 15.1
  8. f417-1 RA: 03 12 31.47 Dec: -27 50 46.5
  9. f466-1 RA: 21 56 02.40 Dec: -29 19 29.9
  10. f467-1 RA: 22 09 07.17 Dec: -27 24 38.5
  11. f468-1 RA: 22 32 26.17 Dec: -31 12 12.1
  12. f469-1 RA: 23 05 43.34 Dec: -30 39 01.0
  13. f470-1 RA: 23 19 39.65 Dec: -29 31 26.1
  14. f471-1 RA: 23 47 38.91 Dec: -28 08 28.3

UBVR Sequences

These sequences were observed on 14 September 1996, and 25 September - 2 October 1997 by Scott Croom. RA and Dec for the field centres are shown next to the field names. Each file has the following format:

object name, RA(J2000) hh mm ss.ss, Dec(J2000) dd mm ss.s, B mag, B error, B(25) mag, s/g, U mag, U error, U(25) mag, V mag, V error, V(25) mag, R mag, R error, R(25) mag

1996 sequences

  1. f409-2 RA: 00 02 56.49 Dec: -29 22 16.6
  2. f416-2 RA: 02 47 31.70 Dec: -30 18 30.5
  3. f466-2 RA: 21 54 17.07 Dec: -29 50 48.0

1997 sequences

  1. f410-2 RA: 00 21 52.31 Dec: -29 48 21.6
  2. f411-2 RA: 00 49 47.87 Dec: -29 09 40.0
  3. f413-2 RA: 01 34 41.60 Dec: -29 36 39.9
  4. f414-2 RA: 02 01 38.73 Dec: -30 42 33.0
  5. f417-2 RA: 03 06 29.09 Dec: -29 40 28.1
  6. f467-2 RA: 22 13 13.45 Dec: -30 03 07.2
  7. f468-2 RA: 22 44 16.60 Dec: -30 02 13.8
  8. f470-2 RA: 23 26 02.57 Dec: -29 22 29.4
  9. f471-2 RA: 23 48 58.85 Dec: -30 01 19.0
We would like to thank the staff at Cerro Tololo Inter-American Observatory for all their help during the period of these observations. 

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mail : scroom@aaoepp.aao.gov.au