Below, you will find two sets of seven charts that when taken together present two light curve for QQ Vul, an AM Her type star. taken two days apart. For an explanation of the charts, please click here. An image of the field of QQ Vul can be found here. The first curve was created from a series of 90 images, each 140 seconds in duration, with a 30 second interval between each frame. The second contains 74 images taken at the same exposure time and interval. The larger curve in each series shows a roughly sinusodial wave. Note that in the first, the leftmost intersect with the Y axis at 15.2 magnitude. The leftmost X measurement is 0.482. That same magnitude is achieved on the right side of the curve at an X value of about 0.64. The distance between 0.482 and 0.640 represents the period time,since the period for a system of this kind is roughly sinusodial. The delta time of 0.158 days results from the difference. 0.158 days corresponds to 3.79 hours. The first estimate for period is therefore 3.79 hours. See the text below the graphs for continued derivation. |
Computing the period of QQ Vul at 3.70 hours |
Below, you will find two sets of seven charts that when taken together present two light curve for QQ Vul, an AM Her type star. taken two days apart. For an explanation of the charts, please click here. An image of the field of QQ Vul can be found here. The first curve was created from a series of 90 images, each 140 seconds in duration, with a 30 second interval between each frame. The second contains 74 images taken at the same exposure time and interval. The larger curve in each series shows a roughly sinusodial wave. Note that in the first, the leftmost intersect with the Y axis at 15.2 magnitude. The leftmost X measurement is 0.482. That same magnitude is achieved on the right side of the curve at an X value of about 0.64. The distance between 0.482 and 0.640 represents the period time,since the period for a system of this kind is roughly sinusodial. The delta time of 0.158 days results from the difference. 0.158 days corresponds to 3.79 hours. The first estimate for period is therefore 3.79 hours. See the text below the graphs for continued derivation. |
The cycle minimum of 15.76 magnitude occurs at JD 2453649.625, which is 2.005 days after the peak in the earlier diagram. Starting from the period minimum from the first chart at JD 2453647.62, adding 3.76 hours until I come very close to JD 2453649.625, I see that I have added this number of hours 13 times. I come close but not exactly to 2453649.625. I come instead to 2453649.673. As you can see, there is a bit of error in the original estimate. To improve the estimate, I assume that 13 cycles did occur, and they occurred over 2.005 days. Dividing this out, I see an improved value for the period as 3.70 hours per cycle. |
