igmhub / picca

set of tools for continuum fitting, correlation function calculation, cosmological fits...
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Possible issue with rebinning #1063

Closed iprafols closed 2 months ago

iprafols commented 2 months ago

@andreicuceu noted that there is potentially an issue with the way we are doing the rebinning.

Original message by Andrei: I think there's a small bug in picca delta extraction when defining the wavelength grid. These are true continuum deltas for the same forest, run with both picca and qsonic. You can see that for mocks the grid is slightly shifted compared to the data, so the bin centers are at 3599.9, 3600.7, etc. instead of 3600.0, 3600.8, etc.. QSOnic has the correct grid, while picca shifts everything by 0.1A to the data grid. This is not a big deal, but it would be good to fix both the bug in picca and the shifted grid in QQ.

issue

iprafols commented 2 months ago

This is not a PICCA issue, that PICCA behaves as expected, but rather a quick quasars issue. While we wait for QuickQuasars to be fixed, it suffices to specify lambda min = 3599.9 and lambda max = 5499.9 in the [data] section in the delta extraction config issue_check