diff --git a/src/toolbox_scs/detectors/hrixs.py b/src/toolbox_scs/detectors/hrixs.py
index 24f87bc7aad902187693b27e73a9971a8957f6f0..7b4840c5dcaa64f14501622ff4ef6a59b4e79634 100644
--- a/src/toolbox_scs/detectors/hrixs.py
+++ b/src/toolbox_scs/detectors/hrixs.py
@@ -244,7 +244,7 @@ class hRIXS:
     ENERGY_INTERCEPT = 0
     ENERGY_SLOPE = 1
 
-    FIELDS = ('hRIXS_det', 'hRIXS_index', 'hRIXS_delay', 'hRIXS_norm')
+    FIELDS = ['hRIXS_det', 'hRIXS_index', 'hRIXS_delay', 'hRIXS_norm']
 
     def set_params(self, **params):
         for key, value in params.items():