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hippke / tls

Transit Least Squares: An optimized transit-fitting algorithm to search for periodic transits of small planets
MIT License
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Period Grid Limits #80

Closed MXK606 closed 4 years ago

MXK606 commented 4 years ago

Hi, I am trying to run TLS with a certain period min. and max. limit but it resorts to using the default values instead.

model = tls(time, flux) results = model.power(period_min=0.1, period_max=60.0) results Transit Least Squares TLS 1.0.24 (21 November 2019) Creating model cache for 29 durations Searching 14400 data points, 2747 periods from 0.601 to 14.833 days Using all 8 CPU threads

I'm not sure what I'm doing wrong here, please could you help me out.

hippke commented 4 years ago

The limitation comes from physics. Shorter periods are unphysical for your chosen mass and radius (the defaults). You can adjust these for shorter periods. On the long side, the default is to have 3 transits. You can set n_transits_min=2 to search for (slightly) longer transits.

MXK606 commented 4 years ago

Ah, right. That makes sense. The reason why I'm setting the upper limit on period so high is because I'm running TLS on simulated light-curves with injected transits of long period planets. So, even if I set n_transits_min=1, it will only search for periods equal to the time series duration.

Is it possible to make TLS search for periods greater than the observation time span?

hippke commented 4 years ago

With n_transits_min=1 you already have activated the search for single transits. If one is found, the estimated period will be the duration of your light curve. Of course, it can be longer in reality. But there is no way (and no need) to adjust the search beyond single transits.