From bab0f4cd29945a766102de99889156111eb11c49 Mon Sep 17 00:00:00 2001
From: Michal Broz <Michal.Broz@cern.ch>
Date: Sun, 24 May 2026 08:12:55 +0200
Subject: [PATCH] Photon energy in header

---
 .../PWGUD/external/generator/GeneratorStarlight.C      | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/MC/config/PWGUD/external/generator/GeneratorStarlight.C b/MC/config/PWGUD/external/generator/GeneratorStarlight.C
index b2069c16b..be7e4d367 100644
--- a/MC/config/PWGUD/external/generator/GeneratorStarlight.C
+++ b/MC/config/PWGUD/external/generator/GeneratorStarlight.C
@@ -337,6 +337,16 @@ class GeneratorStarlight_class : public Generator
   return true;
   }
 
+  //Store couple of event informations to the MC event header
+  void updateHeader(o2::dataformats::MCEventHeader* eventHeader)override
+  {
+    using Key = o2::dataformats::MCInfoKeys;
+
+    eventHeader->putInfo<std::string>(Key::generator, "STARlight");
+    eventHeader->putInfo<std::string>(Key::processName, mSelectedConfiguration);
+    eventHeader->putInfo<float>("photonEnergy", getPhotonEnergy());
+  }
+
    protected:
    float eCM = 5020; //CMS energy
    int projA=208;	//Beam