So far original Selection 1 looks optimal.

Peaks in

...

Whiskers

...

region

Parameters

Set in psana.cfg file peak selection parameters pretty much the same as in Arc region

...

Code Block
if npix>42 : return False if r<100 : return False if r>460 : return False

Combined analysis for Arc and Equ regions

Peak finding in psana

In psana event processing the same peak definition parameters were used for Arc and Equ regions:

Code Block
[ImgAlgos.NDArrDropletFinder:Equ] ... threshold_low = 10 threshold_high = 150 peak_radius = 3

All peaks found in the event were saved in the peak table file without additional selection.

Peak selection in file processing

Arc region selection

Code Block
if atot<2500 : return False if npix>42 : return False if r<434 : return False if r>444 : return False if phi<150 and phi>-150 : return False

Equ region selection

Code Block
if npix>42 : return False if r<100 : return False if r>420 : return False

Event selection

Code Block

def eventIsSelected() :
    sp.event_is_selected = False
    if sp.count_arc_pks_sel != 2 : return False
    if sp.count_equ_pks_sel  > 5 : return False
    if sp.count_equ_pks_sel  < 1 : return False
    sp.event_is_selected = True
    return True

For events with exactly two peaks in Arc region orientation is evaluated as an average angle: orient = (phi1 + phi2) / 2:

Image AddedOrientation distribution shows that in many ~2/3 (left and right peaks) of events two peaks are close to each other... Presumably single peak is split for two or more peaks. Further we select clean events from central peak only: