zclaytor
commented
2 months ago Hi Ilay, Thanks for reaching out, and sorry it took so long for me to see your message. Antipolar spots are not currently implemented in Butterpy, only correlated emergence near existing large spots. This is admittedly a shortcoming of the code, and I'd like to implement it as an option in a future release. If this is a feature you need for your research, let me know and maybe we can figure out a temporary solution.
I'll add that even without the antipolar spots, I found half-period aliases in the simulated TESS-like light curves using Lomb-Scargle and wavelet power spectra (see Fig. 4 of my paper that you linked). I haven't dug into this much, but it appears that antipolar spots are not always needed to yield a half-period alias.
Hope this helps! Zach
Hi, I was reading your paper from 2022 where you presented Buttrepy. I also used it to generate light curves. Great work! I had a question regarding spots longitudes - in your paper you mentioned that spots longitude is usually close to existing spots and sometimes antipolar to them. Indeed, Berdyugina and Usoshkin found that spots on the sun formed in a preferred longitudes separated by 180 degrees. Is this implemented in Butterpy? I looked a little bit into the code and found a correlation probability for spots to form in areas that are more active but didn't see evidence of the 180 deg separation. I'm interested in the separation because that would create correlation at half the rotation period as mentioned by McQuillan. Am I missing something? thanks, Ilay