Документ взят из кэша поисковой машины. Адрес оригинального документа : http://star.arm.ac.uk/preprints/2014/654/photometry/McDonald/Notes Дата изменения: Mon Feb 17 21:32:57 2014 Дата индексирования: Sun Apr 10 12:24:10 2016 Кодировка: Поисковые слова: http www.astronomy.com

Notes concerning photometric observations from McDonald Observatory for YY Gem
campaign, 4-6 March 1988

The observations were made by Marion Frueh with the 0.91m MCD telsecope at
McDonald Observatory. The photomultiplier employed was a cooled EMI 9658A #2(LZ)
with 1350 volts HT. For most of the run, the diaphragm used was 1mm (17 arc
secs) but occasionally when the star was low, the larger 2mm diaphragm was used.

The colour equations were derived from observations made on 22 March
1988 of 17 equatorial standards previously observed by Moffat and Barnes (1979).
Mean extinction coefficients were employed with any small changes taken up in
the zero points of the colour equations by reference to the three local
standards: A (BD+32 degs 1577), B (BD+31 degs 1611) and C (BD+31 degs 1629).

The following transformation equations to the Johnson UBVRI and Cape/Kron RI
systems were derived by least squares:

V = v -0.0543(b-v) + 1.07
(B-V) = 0.875(b-v) + 0.80
(U-B) = 1.15(u-b) - 0.78
(V-R) = 1.58(v-r) - 0.584
(R-I) = 1.021(r-i) + 2.554
(V-R)kc = 0.956(v-r) - 0.28
(R-I)kc = 0.85(r-i) + 2.12

The Moon was full and sky conditions are described under the comments below.

The file yygem-4-5-6mar88.dat contains the reduced photometric data in the
following columns:

column 1 UT (hrs)
column 2 HJD
column 3 sec Z
column 4 U
column 5 B
column 6 V
column 7 R
column 8 I
column 9 Rkc
column 10 Ikc
column 11 U-B
column 12 B-V
column 13 V-R
column 14 R-I
column 15 (V-R)kc
column 16 (R-I)kc

Individual comments by the observer:

4 March 1988 UT=7.936 - 7.947 poor tracking, extraneous U observation
UT=7.974 ditto
UT=8.006 ditto
seeing 3-8 arc secs

5 March 1988 UT=3.887 guiding error
UT=5.610 ditto
UT=5.679 - 5.711 wind buffeting telescope
UT=8.443 - 8.459 Seeing poor 5-20 arc secs
seeing 2-3 arc secs at beginning of observations