J/A+A/406/829 Background galaxies in the WSRT wide-field Survey (Braun+, 2003)
The WSRT wide-field HI survey: I The background galaxy sample
Braun R., Thilker D., Walterbos R.A.M.
<Astron. Astrophys. 406, 829 (2003)>
=2003A&A...406..829B 2003A&A...406..829B
ADC_Keywords: Galaxies, rotation; Redshifts; H I data
Keywords: Galaxies: distances and redshifts -- Galaxies: evolution --
Galaxies: formation -- Galaxies: fundamental parameters --
Galaxies: luminosity function, mass function
Description:
We have used the Westerbork array to carry out an unbiased wide-field
survey for H I emission features, achieving an RMS sensitivity of
about 18mJy/beam at a velocity resolution of 17km/s over 1800deg2
and between -1000<VHel<+6500 km/s. The primary data consists of
auto-correlation spectra with an effective angular resolution of 49'
FWHM. The survey region is centered approximately on the position of
Messier 31 and is Nyquist-sampled over 60x30 deg in RAxDec. In this
paper we present the results for our HI detections of external
galaxies at positive Local Group Standard of Rest (LGSR) velocity.
We detect 155 external galaxies in excess of 8 sigma in integrated
HI flux density. Plausible optical associations are found within a
30' search radius for all but one of our HI detections in DSS images,
although several are not previously catalogued or do not have
published redshift determinations. Our detection without a DSS
association is at low galactic latitude. Twenty-three of our objects
are detected in HI for the first time. We classify almost half of our
detections as "confused", since one or more companions is catalogued
within a radius of 30' and a velocity interval of 400km/s. Nine of the
detected galaxies fall so near the edges of the survey coverage
(either spatially or in velocity) that their parameters can not be
reliably determined. These nine objects are excluded from the enclosed
table.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
wsrtgals.dat 80 146 Properties of HI detected Galaxies
--------------------------------------------------------------------------------
Byte-by-byte Description of file: wsrtgals.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Name formed from truncated J2000 RA, +DEC
12- 13 I2 h RAh Right ascension (J2000)
15- 16 I2 min RAm Right ascension (J2000)
18- 19 I2 s RAs Right ascension (J2000)
21 A1 --- DE- Declination sign
22- 23 I2 deg DEd Declination (J2000)
25- 26 I2 arcmin DEm Declination (J2000)
28- 29 I2 arcsec DEs Declination (J2000)
31- 34 I4 km/s HRV Heliocentric radial velocity
36- 38 I3 km/s W20 Velocity profile width at 20% of peak
40- 44 F5.1 Jy.km/s Flux Total HI Flux at 1410MHz
46- 49 F4.2 Jy.km/s e_Flux Error in total HI Flux
51- 55 F5.2 [solMass] MHI Logarithm of HI Mass in Solar Masses
57- 68 A12 --- ID Catalog Name of most plausible optical ID
70- 71 A2 --- Notes Note about optical ID (1)
73- 76 F4.1 arcmin Offset Angular offset of detection with optical ID
78- 80 I3 --- Confu Confusion index (2)
--------------------------------------------------------------------------------
Note (1):
c: confused source (catalogued companion within 30arcmin and 400km/s)
?: source without a previous redshift determination
o: significant centroid offset of ID, but less than 10 kpc
+: significant centroid offset of ID, larger than 10 kpc, but s/n < 10
++: very significant centroid offset of ID, larger than 10 kpc and s/n > 10
Note (2):
A three digit "confusion" index, "abc" enumerating the number of
catalogued companions (truncated at 9) within a 30 arcmin radius which are
(a): within 400 km/s
(b): between 400 and 1000 km/s
(c): of unknown redshift
--------------------------------------------------------------------------------
(End) Robert Braun [Astron] 12-Aug-2003