Default offset in configuration, and produced IRFs at cluster

[juanjq]

In the standard IRF and DL3 configuration file the FoV offset is set to be [0.1, ... 1.1] deg

cta-lstchain/docs/examples/irf_dl3_tool_config.json

Line 42 in 6db577d

"fov_offset_min": 0.1,

Is this done with some purpose?, in order to create SkyMaps, in the way gammapy works, passing those parameters will create a hole in the middle for effective area and then also exposure.

In one analysis call was mentioned that for the standardization of DL3 production [0, 0.5, 1.0, 1.5, 2.0, 2.5] deg will be the binning used. What makes sense to me much more than the default one. I don't know if there is maybe a reason to not change it.

Directly linked to this, I was checking for the already produced IRFs at cluster, produced by @vuillaut and I noticed two things:

• In the latest production 20250212_v0.10.17_allsky_interp_dl2_irfs_nsb_* the binning applied is the default one, that can be read from the irf itself or from IRFFITSWriter.provenance.log, so containing that hole in the effective area.

• But in the next production 20240918_v0.10.12_allsky_nsb_tuning_* the binning applied is not the default, is just one bin, [0.006, 2.503] deg, and in the IRFFITSWriter.provenance.log the configuration that is written is the default one, so the IRF file itself is not consistent with what is written in the IRFFITSWriter.provenance.log or lstchain_config_nsb*.json. I add a piece of code that can be used to see that in the IRF there is only one bin in this case.

from astropy.io import fits

path = "/fefs/aswg/data/mc/IRF/AllSky/20240918_v0.10.12_allsky_nsb_tuning_0.22/TestingDataset/GammaDiffuse/dec_4822/node_corsika_theta_29.249_az_319.533_/"
file = path + "irf_20240918_v0.10.12_allsky_nsb_tuning_0.22_GammaDiffuse_dec_4822_node_corsika_theta_29.249_az_319.533_.fits.gz"

a = fits.open(file)
print(a["EFFECTIVE AREA"].data["THETA_LO"], a["EFFECTIVE AREA"].data["THETA_HI"][0])