Dauban V244


nameDauban V244
constellationCyg
J2000.019 32 45.98 +36 06 13.1
other names2MASS J19324597+3606131
typeEA
mag range13.4 - 14.7 CR
period (days)--
epoch--
colorJ-K = 0.30
remarks--
links--
discovery11/12/2012
DSS2-R
DSS2-IR


Confirmation of variability


Additional observations have been made with a 200mm reflector. The data confirms the occurrence of eclipses.



Photometric data


We provide magnitude data in the tables below. All the images have been carefully checked prior to photometry based on the following criteria: (1) normal value of magnitude zero point, (2) sky background is uniform across the image, (3) air mass < 2.5, (4) stars are sharp and not elongated in the E-W direction, (5) for the 80mm refractor only: accuracy of astrometric reduction is better than 0.5 pixel.

For the 80mm refractor, three 10 sec exposures are taken. The magnitudes are measured on the median of the three images.

For the 200mm reflector, the exposure and number of images taken is changing. The magnitudes values are measured on each individual image. For each night, a median is taken over several consecutive measurements to obtain the final magnitudes reported in the table. The number of values used for the median is indicated in the table third column. If it is greater than 3 the data is very reliable. If only 1 image was used, the data is probably fine but we cannot guarantee it does not contain an error.

Dauban Survey (80mm F/7.5 refractor)
Julian dateCR magnitude
2456203.38023513.488
2456208.28663713.498
2456214.26458913.747
2456220.27998613.456
2456221.26464713.840
2456237.24704213.400
2456244.23811113.533
2456248.23599913.623
2456249.26764913.519
2456250.35917213.845
2456251.23450313.469
2456262.24014314.714
2456268.25052113.896
2456273.26090313.523
2456279.23141113.950
2456300.24124413.623
2456401.48182413.378
2456438.47023113.569
2456451.48248113.509
2456490.51547113.646
2456504.63413313.536
2456517.36043814.805
2456541.46459715.087
2456556.46472613.481
2456557.31445413.485
2456571.31846013.539
LX200 (200mm F/10 reflector)
Julian dateCR magnitudenumber of images
used for photometry
2456504.35633713.49915
2456504.39933113.47315
2456504.44348113.46415
2456504.48763513.48215
2456504.53189213.49415
2456505.40307214.4603
2456505.42297514.3243
2456505.44278514.0273
2456505.46252313.8743
2456505.48249113.7913
2456506.33754013.5453
2456506.35621913.5463
2456506.37503913.5283
2456506.39459513.4903
2456507.35611413.5311
2456507.35628413.5001
2456507.35644513.5011
2456508.35410613.4563
2456508.37255813.4583
2456508.39072613.4303
2456508.40919613.4503
2456508.42776013.4693
2456509.36155313.5593
2456509.37820913.4843
2456509.39530113.4803
2456509.41270413.6163
2456510.34169713.6051
2456510.34185513.6381
2456510.34201313.4971
2456513.34988513.4871
2456513.35005313.5061
2456513.35021913.4761

Period search


Eclipses have been observed at these dates:

Eclipse julian dates
2456262.240143
2456505.403072
2456517.360438
2456541.464597


A period search gives the following phase residual:



Possible periods are:

Possible periods
12.15 days
6.074 days
5.935 days
4.050 days
3.987 days
3.002 days