Question on how forced photometry will be run on images taken after a DIAObject is detected. Again, using LSE-163 Data Products and Definitions, Juric et al. 2019-07-29. - section 3.2.1 states :
“For all DIAObjects overlapping the field of view … forced photometry will be performed on the difference images. Those measurements will be stored as DIAForced- Sources. No alerts will be issued for these DIAForcedSources, but the DIAForcedSource measurements will be included in any future alerts triggered by a new DIASource at that location.”
I take this to mean that a DIASource which is found with through the DIAForcedSource photometry with S/N>5 will have an alert issued.
But what if the DIAForcedSource produces a measurement S/N < 5 ? Where will this information be stored - the Prompt Products Database ?
If so, then 3 questions
- on what timescale will it be available, 24hrs ?
- For how long will such forced photometry be run ? The whole survey ?
- Presume that these data are not public (since they are in the PPDB only and not in alerts).
A strong science case for accessing forced photometry after detection of a transient is fast declining transients e.g. kilonovae, NS-WD mergers. A detection followed by a non-detection is often as interesting as the other way round.