From c8791a616c0b0dbb61d2a20da30c23635b738a77 Mon Sep 17 00:00:00 2001
From: Artur Glavic <artur.glavic@psi.ch>
Date: Wed, 9 Sep 2026 14:37:17 +0200
Subject: [PATCH] Add flipper log delay correction

---
 eos/options.py                | 9 +++++++++
 eos/reduction_reflectivity.py | 4 +++-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/eos/options.py b/eos/options.py
index 5a9aebd..5c47129 100644
--- a/eos/options.py
+++ b/eos/options.py
@@ -499,6 +499,15 @@ class ReflectivityReductionConfig(ArgParsable):
                 },
             )
 
+    flipperMaxDelay: int = field(
+            default=4,
+            metadata={
+                'short': 'fmd',
+                'group': 'data manicure',
+                'help':  'Remove all neutron pulses that are within flipperMaxDelay of a change in spin state',
+                },
+            )
+
 class OutputFomatOption(StrEnum):
     Rqz_ort = "Rqz.ort"
     Rqz_orb = "Rqz.orb"
diff --git a/eos/reduction_reflectivity.py b/eos/reduction_reflectivity.py
index 7d92b88..3b75bc9 100644
--- a/eos/reduction_reflectivity.py
+++ b/eos/reduction_reflectivity.py
@@ -185,7 +185,9 @@ class ReflectivityReduction:
                 for pi in pols:
                     plabel = const.polarizationLabels[pi]
                     pol_filter = FilterByLog(f'polarization_config_label=={pi}',
-                                             remove_switchpulse=True) | ApplyMask()
+                                             remove_switchpulse=True,
+                                             pre_switch=self.config.reduction.flipperMaxDelay
+                                             ) | ApplyMask()
                     logging.info(f'    filter {plabel} using polarization_config_label=={pi}')
                     pol_filter(self.dataset)
                     self.dataset.update_header(self.header)