J/AJ/108/1987 The SSRS2 Sample (Alonso+ 1994)
CCD Calibration of the Magnitude Scale for the SSRS2 Sample:
The Equatorial Region
Alonso M.V., da Costa L.N., Latham D.W., Pellegrini P.S., Milone A.A.E.
<Astron. J. 108, 1987 (1994)>
=1994AJ....108.1987A 1994AJ....108.1987A
ADC_Keywords: Galaxies, optical; Galactic pole, north; Galactic pole, south;
Photometry, CCD; Magnitudes
Abstract:
In this paper we continue our investigation on the isophotal nature,
accuracy, and uniformity of the magnitude system adopted in the
Southern Sky Redshift Survey extension (SSRS2). Extending our earlier
work, we examine galaxies in the equatorial region, primarily in the
declination range -17.5 deg ≤ Dec. ≤ 0 deg, over a large range of
right ascension, covering the southern and northern Galactic caps. For
this purpose, we have obtained CCD isophotal magnitudes in the B and R
bands for 265 galaxies of different morphological types. Using this
larger sample we confirm our earlier claim that the m(SSRS2) magnitudes
are very nearly the magnitude measured within the isophote mu_B = 26
mag/arcsec^2, with a dispersion of about 0.30 mag. The relative
zero-point offset between our m(SSRS2) magnitudes and CCD photometry is
-0.02 mag from all data we have obtained. However, we detect a
variation of the zero-point across different regions of the sky of ±
0.10 mag for regions at large angular separations. We also estimate
that the zero-point offset between the m(SSRS2) and Zwicky systems is
relatively small (∼0.10 mag), which should allow us to combine the data
from the SSRS2 and the CfA2 Redshift Survey.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 63 265 Galaxy sample
notes1.dat 79 90 Notes to table 1
table2.dat 56 238 Isophotal magnitudes for observed galaxies
table1.tex 86 543 TeX version of Table 1 and notes
table2.tex 108 417 TeX version of Table 2
useful.tex 78 42 Macro package required by TeX files
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1-12 A12 --- Galaxy Name of the galaxy
13-21 A9 --- StScI Space Telescope Science Institute Id.
22-24 I3 h RAh Right ascension 1950.0
25-27 I3 min RAm R.A.
28-32 F5.1 s RAs R.A.
34 A1 --- DE- Sign declination
35-36 I2 deg DEd Declination 1950.0
37-39 I3 arcmin DEm Dec.
40-42 I3 arcsec DEs Dec.
43-46 I4 --- Type []? Morph. type, Corwin 1993, private comm.
47-53 F7.2 mag mSSRS2 []? SSRS2 magnitude
54-59 F6.1 mag mMCG []? Morphological Cat. of Galaxies magnitude
61-63 A3 --- Note *Note flags
--------------------------------------------------------------------------------
Note on Note:
1 - Galaxies in common with ESO-LV.
2 - Galaxies in common with CGCG.
3 - Surface brightness profiles used in the comparisons with
other authors.
* - Comments on Individual Galaxies (see notes1.dat)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: notes1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1-80 A80 --- Note Text of note for object marked with '*' in
field 'Note' in table1.dat
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1-12 A12 --- Galaxy Name of the galaxy
14-18 A5 --- Date Observation date
19-25 F7.2 mag mB26 *CCD magnitude m_B(26)
26-30 F5.2 mag e_mB26 Associated error in mB26
31-37 F7.2 mag mR26 *CCD magnitude m_R(26)
38-42 F5.2 mag e_mR26 Associated error in mR26
43-49 F7.2 --- muBlim Limiting blue isophote, mu_{B,lim}
50-56 F7.2 --- muRlim Limiting red isophote, mu_{R,lim}
--------------------------------------------------------------------------------
Note on mB26:
CCD magnitude m_B(26) as measured within (or extrapolated to) the
isophote mu_B = 26 mag/arcsec^2
Note on mR26:
CCD magnitude m_R(26) as extrapolated to the isophote
mu_R = 26 mag/arcsec^2
--------------------------------------------------------------------------------
Origin: AAS CD-ROM series, Volume 4, 1995 Lee Brotzman [ADS] 05-May-1995
(End) [CDS] 10-Jul-1995