OST ppm noise floor

[rodluger]

I want to tie in our OST discussion with Figure 14. I argue that if orbital parameters are well known, distinguishing between an airless and a thick atmosphere c requires the sensitivity to a ~80 ppm signal. If the orbital parameters are unconstrained, the signal we're looking for is the asymmetry of the light curve, which is ~10 ppm. Jake, can you calculate what the sensitivity of OST is at 50 microns? I imagine this is just the size of the error bars in ppm, right? That would be the "noise floor" for a 1-sigma detection. We should then calculate how many exposures we would need to stack to get down to 10 ppm. Can you do this?

[jlustigy]

For a 5 min cadence with our OST setup, I find that 11 stacked observations reaches 10 ppm precision on the lightcurve. [image: Inline image 1]

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On Thu, Jul 13, 2017 at 9:38 AM, Rodrigo Luger ***@***.***> wrote: Assigned #30 <#30> to @jlustigy <https://github.com/jlustigy>. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#30 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AIeJIhkk3k9tqCPhBgzV9obyLlRWOSeSks5sNkf2gaJpZM4OXQFH> .

-- Jacob Lustig-Yaeger Astronomy & Astrobiology Graduate Student University of Washington jlustigy.github.io

[jlustigy]

Bad news: I had a bug in my custom filters where I was extrapolating them far beyond their specified boundaries. So now we would have to observe ~500 (!) events to reach 10 ppm precision. Sorry about that! But I also made a figure of SNR on an occultation of c by b as a function of wavelength from ~10-80 microns, which shows a rise up to ~15-20 microns as the contrast increases, then a decline beyond that as there are fewer and fewer photons to detect. [image: Inline image 1] On Fri, Jul 14, 2017 at 3:15 PM, Jacob Lustig-Yaeger <jlustigy@uw.edu> wrote:

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For a 5 min cadence with our OST setup, I find that 11 stacked observations reaches 10 ppm precision on the lightcurve. [image: Inline image 1] On Thu, Jul 13, 2017 at 9:38 AM, Rodrigo Luger ***@***.***> wrote: > Assigned #30 <#30> to > @jlustigy <https://github.com/jlustigy>. > > — > You are receiving this because you were mentioned. > Reply to this email directly, view it on GitHub > <#30 (comment)>, > or mute the thread > <https://github.com/notifications/unsubscribe-auth/AIeJIhkk3k9tqCPhBgzV9obyLlRWOSeSks5sNkf2gaJpZM4OXQFH> > . > -- Jacob Lustig-Yaeger Astronomy & Astrobiology Graduate Student University of Washington jlustigy.github.io

-- Jacob Lustig-Yaeger Astronomy & Astrobiology Graduate Student University of Washington jlustigy.github.io