I am looking into incremental templates during year 1 of the survey for a short paper in the ApJS focus issue. I want to see how the area of sky that meets the requirements for a creating a template changes in the early survey, and thus when a field can start generating alerts.
Can anyone please advise or point me to some documentation on the requirements for creating a good template image? I’ve seen in https://rtn-011.lsst.io/ & https://dmtn-107.lsst.io/ that a minimum of three images are needed in year 1, but are there any specific limits on seeing and image depth for example?
@ebellm, @isullivan will have better answers.
I don’t think there are currently any requirements on either of image depth or seeing, although obviously there would be an impact on the quality of image differencing.
We haven’t yet done the detailed analysis needed to set these limits. We intend to keep the incremental templates in place as they are first built until the first Data Release to avoid repeated baseline changes. Accordingly there is a tradeoff between early template production (which enables more alerts) and the quality and spatial coverage of those templates.
I expect that we will need a combination of analysis based on the cadence simulations as well as early commissioning data to finalize the incremental template generation plan.
Cool, thanks Lynne and Eric for the information! Perhaps when I am simulating the generation of templates in this small project I can assign some sort of quality factor to a template based on the seeing etc. of the component images. Might be useful for an initial assessment of this trade-off.
Sounds great, that will be very helpful–looking forward to seeing your paper!