Narrowband SN imaging program


This program will obtain narrowband imaging in the SN fields having deep NIR data but not yet having images from N964. Detection of emission lines in this filter can be used to check or improve the n(z) determinations in these fields, as well as search for strong line-emitting galaxies. We need z band taken before and after to veto variable objects.


For now, we don't know of any restrictions besides significant coulds. Based on observations taken under varying conditions related to moon we make add restrictions here, but for now take regardless of moon phase (although pick a field that's not too close to the moon if possible).

Observer instructions

When conditions are good, place the narrowband JSON scripts onto SISPI's queue. Scripts are attached to this page and already downloaded to `DECamObserver/ExposureScripts/DES_scripts`. Each script does a cycle of z and N964 exposures and will take approx 1 hour. You can repeat the scripts on a given field if seeing remains poor.

Transit times can be found here: .

What to do if conditions improve

Un-queue remaining narrow-band exposures, but finish off with at least two z-band exposures to be able to veto variable objects before you continue survey mode.

If you have left an observing block unfinished, but seeing again deterioates later in the night, it's preferable to do the same field again.

Status / Choosing right field

So far no field has had a complete observing block. Priorities:

  • Always pick E2 if it is within the "green circle" on Alex Drlica-Wagner's monitor, i.e. airmass < 1.4; repeat as long as possible
  • Only if E2 is not visible, do whichever of X3 or C3 has the lowest airmass