107  CH URSAE MAJORIS   (UG)   Range: 10.7-14.9V
     Position:   10 07 00.81  +67 32 47.7 (J2000, from .dat file)
     Magnitude:  V=14.933  B-V=0.691      (in .dat file)

ID     RA  (2000)   DEC       X    Y   N    V      ERR     B-V    ERR   

a) Comparison star sequence
  
1    10 08 15.9  +67 38 59   429  371  4  12.108  0.005   0.487  0.021   
2    10 06 06.9  +67 29 27  -309 -201  3  12.782  0.000   0.631  0.013   
3    10 08 09.6  +67 35 50   393  182  4  12.847  0.005   0.965  0.019   
4    10 08 14.7  +67 38 09   422  321  4  13.297  0.000   0.499  0.019   
5    10 07 01.6  +67 27 31     5 -317  3  14.180  0.005   0.755  0.017   
6    10 07 39.3  +67 29 02   221 -226  3  14.325  0.011   0.709  0.014   
7    10 06 53.8  +67 39 29   -40  401  4  14.828  0.010   0.877  0.020   
8    10 06 43.6  +67 38 36   -98  348  4  14.973  0.016   0.507  0.037   
9    10 07 07.9  +67 31 21    41  -87  7  15.271  0.015   0.622  0.037   
10   10 07 01.3  +67 28 31     3 -257  3  15.658  0.006   0.514  0.015   
11   10 08 25.6  +67 32 29   486  -19  4  15.984  0.021   0.794  0.031   
12   10 07 12.8  +67 29 29    69 -199  3  16.608  0.022   0.720  0.021   
13   10 06 37.1  +67 31 23  -136  -85  3  17.727  0.061   1.181  0.076   


b) Wide-colour extension for CCD calibration

     10 08 07.7  +67 31 05   384 -103  4  14.917  0.019    0.630  0.040   
     10 06 40.6  +67 27 06  -116 -342  3  14.387  0.016    1.491  0.007   


Notes:

The quiescent magnitude quoted above is the minimum value determined 
from three nights of photometry. However the B-V value is too red 
for a dwarf nova, and it is possible that CH UMa is hidden under this
red star.

The following AAVSO Pv magnitudes are from the preliminary 'e' chart 
dated 4/1993:

                  ID   Henden     AAVSO
                  1    12.108     12.0
                  2    12.782     12.7
                  3    12.847     12.7
                  4    13.297     13.1
                  5    14.180     13.7
                  6    14.325     14.0
                  9    15.271     15.1
                  10   15.658     15.3

Bruce Sumner
Revised 31 July 1999