Dauban V241


nameDauban V241
constellationVul
J2000.019 43 58.12 +26 20 59.1
other names2MASS J19435812+2620591
typeEA
mag range13.7 - 15.3 CR
period (days)--
epoch--
colorJ-K = 0.63
remarks--
links--
discovery15/11/2012
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
2456190.34332713.950
2456195.37132013.780
2456202.34887713.765
2456205.32887013.910
2456206.32101415.358
2456210.29816413.923
2456213.28454214.940
2456219.27928513.747
2456225.27753713.704
2456230.27480313.908
2456234.27713214.686
2456238.26252513.735
2456243.30169613.780
2456247.27109813.733
2456250.25481413.802
2456263.25993213.897
2456271.24962913.821
2456288.25491713.900
2456401.59276614.466
2456451.49830813.819
2456461.40474013.980
2456474.54894013.926
2456485.43398215.181
2456502.38240113.688
2456516.56419913.959
2456523.37098813.914
2456540.41848613.895
2456549.51561813.789
2456558.39857813.871
2456566.38819913.669
LX200 (200mm F/10 reflector)
Julian dateCR magnitudenumber of images
used for photometry
2456504.36749913.81414
2456504.41076013.78814
2456504.45502913.7697
2456504.49946913.80010
2456505.40796913.8243
2456505.42788613.7303
2456505.44784513.8253
2456505.46730913.6853
2456505.48752713.7313
2456506.34222815.2123
2456506.36084515.0042
2456506.38021114.7232
2456506.40018214.5113
2456506.43555214.3223
2456507.36105513.7531
2456507.36145413.8531
2456507.36185313.6981
2456508.35904113.8003
2456508.37745113.7463
2456508.39560513.6873
2456508.41390313.8193
2456508.43259313.6823
2456510.34392313.7241
2456510.34431013.7581
2456510.34469813.7251
2456513.35466414.8661
2456513.35506814.8541
2456513.35547214.7111

Period search


Eclipses have been observed at these dates:

Eclipse julian dates
2456206.321014
2456213.284542
2456234.277132
2456401.592766
2456485.433982
2456506.342228
2456513.354664


A period search gives the following phase residual:



Possible periods are:

Possible periods
6.9775 days
3.4888 days
2.3258 days