% Documentation for The 6C Survey of Radio Sources - VI.  The 
% Zone 30d<Dec<+51d, 00h<RA<09h5m and 22h35m<RA<24h). 
% (Hales, Baldwin and Warner 1993)
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% Document Number:
% Written: October 1993  by N. A. Oliversen
% TeX Ver: October 1993 by N. A. Oliversen
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\documentstyle [adc,11pt]{article}
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\newcommand{\cat}{The 6C Survey of Radio Sources - VI.  The 
 Continuous Zone 30\degree\ $<$ Dec $<$ 51\degree, 00$^{h}$ $<$ RA $<$ 
09$^{h}$05$^{m}$ and 22$^{h}$35$^{m}$ $<$ RA $<$ 24$^{h}$}
\newcommand{\abbr}{6CVI}
\newcommand{\prefp}{Hales, Baldwin, and Warner (1993)}
\newcommand{\docnum}{ADC }
%
\begin{document}
%
\title{The 6C Survey of Radio Sources - VI.  The 
 Continuous Zone \\ 30\degree\ $<$ Dec $<$ 51\degree, 00$^{h}$ $<$ RA $<$ 
09$^{h}$05$^{m}$ and 22$^{h}$35$^{m}$ $<$ RA $<$ 24$^{h}$}
\author{\prefp}              
\docauthor{N. A. Oliversen}
\date{October 1993 \\ Revised March 1994}
\docno{NSSDC/WDC-A-R\&S 93-33}
\maketitle
\date{}

\begin{abstract} This catalog contains the sixth section of the 6C
Cambridge survey of radio sources at 151 MHz (6CVI).  This part of the
survey covers the region 30\degree\ $<$ Dec $<$ 51\degree,
$00^{h}<RA<09^{h}05^{m}$ and $22^{h}35^{m}<RA<24^{h}$. The catalog
data include the source positions (B1950), peak flux density,
integrated flux density, contour map panel number, contour map field
names, and an integrated flux flag.  This catalog contains a list of 
6752 sources in 2440 square degrees.  

\end{abstract}

\section{Introduction}

{\bf A copy of this document should be distributed with every 
copy of the machine-readable catalog.}

\subsection {Description}

{\it \cat} (\abbr) contains a compilation of radio source observations
made with the use of an (non-tracking) Earth-rotation aperture
synthesis telescope comprising many small aerial arrays on an
east-west baseline operating at 151 MHz.  This paper is the sixth in
a  series of papers giving radio source observations at 151 MHz.  See
the discussion in 6CI (Baldwin et al. 1985) for details on the design
and operation of the telescope and the initial generation of the
survey.  Other papers in this series include 6CII (Hales et al. 1988),
6CIII (Hales et al. 1990), 6CIV (Hales et al. 1991), and 6CV (Hales
et al. 1993a). 

The 6CVI catalog contains a total listing of 6752  radio sources
ordered by increasing right ascension.  The 6CVI covers the 
region 30\degree$<Dec<$ 51\degree,
$00^{h}<RA<09^{h}05^{m}$ and $22^{h}35^{m}<RA<24^{h}$.  This
survey has been divided into six fields with up to 32 panels per
field.  The 6CVI has some overlap in right ascension
with the 6CII catalog so that 199 sources have alternative entries
in both catalogs.  In addition, there is some overlap with the 6CIII
and 6CV papers in this series. 

Positional calibration was effected as for 6CII except that
a separate constant right ascension correction was obtained for 
each map as well as a separate declination correction varying linearly 
with declination.  The right ascension correction ranged from
0.18 sec to 0.79 sec, and the most severe declination correction
reached -25''.

Flux densities are on the scale of Roger et al. (1973).
Provisional flux densities were corrected for the measured
receiver gain at a declination of 41\degree\ as a function of right
ascension. The final flux densities were adjusted to be consistent
with the radio sources in other published radio source lists and
were adjusted for consistency with overlapping regions in the 6CIII,
6CV catalogs. See \abbr\ for additional flux calibration
details and for source selection criteria.

Note that this ADC catalog contains only the radio source 
list and does not include the radio maps.  The radio source list
is intended to be used with the radio maps originally published on 
microfiche in \prefp.  

\subsection{Reference}
\begin{references}
\item Hales, S. E. G., Baldwin, J. E., and Warner, P. J. 1993, MNRAS,
263, 25. 

\end {references}

\section {Structure}
\subsection{The File as a Whole}

{\it \cat} consists of a single fixed-block file consisting of 6752
52-byte records. Descriptions of some of the fields in the file are
given in the following section.

\subsection{Catalog File}

\begin{table}[h]
\centering
\begin{tabular}{ c c c l }
\hline\hline
         &         &Suggested &                \\
Bytes    & Units   &  Format  & \multicolumn{1}{c}{Item}     \\
\hline
 1- 2    & h       & I2    & Right ascension (B1950)  \\
 4- 5    & min     & I2    & Right ascension (B1950) \\
 7-10    & s       & F4.1  & Right ascension (B1950) \\
12-14    & \degree\  & I3    & Declination (B1950) \\
16-17    & $'$     & I2    & Declination (B1950) \\
19-20    & $''$    & I2    & Declination  (B1950) \\
23-27    & Jy      & F5.2  & Flux density (peak)  \\ 
30-34    & Jy      & F5.2  & Flux density (integrated) \\
37-39    &         & I3    & Contour map panel number\\
42-48    &         & A7     & Contour map field name \\
   51    &         & A1    & Integrated flux flag \\
\hline\hline
\end{tabular}
\caption{Catalog Record Format}
\label{t:catfig}
\end{table}

{\bf Flux density (peak):} Source peak flux density at 151 MHz.

{\bf Flux density (integrated):} Source integrated flux density
at 151 MHz.   Integrated flux densities were derived for sources
with apparent flux densities above 1 Jy (2 Jy for the top panels of
the map 2340+41 to avoid severe runaway problems).  See \abbr\
for further details on generation of the source list.

\pagebreak

{\bf Contour map panel number:} This column contains the name of the
map panel in which the source appears.  The panel number and map field
name tell the user where to look up the source of interest in the
published contour map.  Each map is divided into 32 panels.  A panel
number listed with a negative sign indicates that the data are
accommodated at the location but come from another map or area of sky.

{\bf Contour map field names:} This column contains the name of the 
field in which the source appears.  Six fields have been included in 
this survey: 2340+41, 0120+41, 0300+41, 0440+41, 0620+41, and 0800+41.  
The panel number and map field name tell the user where to look up
the source of interest in the published contour map.

{\bf Integrated flux flag:}  A dash (-) indicates that the
peak flux was not strong enough to calculate the integrated flux.
An asterisk (*) indicates that the peak flux
was strong enough to qualify for integration, but it has been
integrated into a brighter adjoining peak.  


\section{History}

\subsection{Remarks and Modification}

{\it \cat} was received by the Astronomical Data Center (ADC), NASA
Goddard Space Flight Center, from Dr. Heinz Andernach.  
The catalog was originally submitted by the first author, Dr. Sally Hales.

The integrated flux flag column was generated by the ADC by editing
the original integrated flux field and moving the character flags to a
separate column.   This was done to avoid the mixing of characters and
numbers in a single field. 


\section{Reference to the Documentation}
\begin{references}
\item {Baldwin, J. E., Boysen, R. C., Hales, S. E. G., Jennings, J. E.,
Waggett, P. C., Warner, P. J., and Wilson, D. M. A.  1985, MNRAS, 217, 
717}
\item {Hales, S. E. G., Baldwin, J. E., and Warner, P. J. 1988, MNRAS, 
234, 919 }
\item {Hales, S. E. G., Masson, C. R., Warner, P. J., and Baldwin, J. E.
  1990, MNRAS, 246, 256}
\item {Hales, S. E. G., Mayer, C. J., Warner, P. J., and Baldwin, J. E.
  1991, MNRAS, 251, 46}
\item {Roger, R. S., Bridle, A. H., and Costain, C. H. 1973, AJ, 78, 
1030}
\item {Hales, S. E. G., Masson, C. R., Warner, P. J., Baldwin, J. E.,
and Green, D. A. 1993a, MNRAS, 262, 1057}
\item {Hales, S. E. G., Baldwin, J. E., and Warner, P. J. 1993b, MNRAS,
263, 25}

\end{references}
\end{document}
