Perseverance has finally paid off! I caught a flare event on the surface of the UV Cet type star V0371 Ori. I've had several attempts that just resulted in no activity, but this last run I captured a flare that appears to have been about 6 minutes in duration. The equipment I use is quite simple, A Mak 127 operating at F6, a cmos ZWO 178MM with a photometric blue filter. Intergration is 60 seconds using Sharpcap Live stacking and MaximDl for analysis and uploaded to the AAVSO
Screenshot 2023-02-11 at 15-45-12 Static Light Curve.png (166.57 KiB) Viewed 1179 times
That looks very impressive. Just trying to understand better what you have done though. So the X axis means Julian Days in a numerical format (which I just looked up on Wikipedia) and the data mean that you have measured the brightness of this star --converting ADUs into magnitudes for for about 30 x 60 s observations per day on the Y axis ?
I am guessing then that most of what you have plotted over the different nights defines the noise and a slight drift in brightness --then with a very clear brightening event.
Is this like 'nova' brightening because of infall of material from a companion star or something?
thanks
Tim
Yes, the time used is the Julian date, which for this lightcurve covers about 5 hours. Each data point is a 60 second exposure. The flare lasted about 6 minutes.
I think the best description of this event would be a Corona mass ejection (CME) similar to the Sun's activity, but much more powerful.
Thanks for the explanation Douglas. One further technical question then if I may. The magnitude estimate looks remarkably constant to a high degree of precision. I have been interested in the possibility of using the SC photometry tool to follow variable star cycles. So I started with an easy one - W-UMa - and had some success but only by using relative magnitude measurements (i.e I followed W-UMa brightness in terms of ADUs but the data only made sense when I expressed these data normalized against the brightness of two adjacent comparator stars of similar magnitude). This was because sky conditions, transparency etc were changing rapidly over the 2h or so that I recorded the data so that absolute measurements were all over the place (but still within the ~ linear range of the camera). Are the magnitude data in your study also similarly normalized - or by some other technique?
Hi Tim, It's best to use comp stars close to your target, good tracking, good calibration and ensure you get a good SNR on all the stars you measure, especially try to avoid bright moonlight and imaging too close to the horizon or heat from radiating buildings/roof tops.
