diff --git a/examples/master/repository/photon_histogram.py b/examples/master/repository/photon_histogram.py
old mode 100644
new mode 100755
index 3bebef1bf..c41e13031
--- a/examples/master/repository/photon_histogram.py
+++ b/examples/master/repository/photon_histogram.py
@@ -13,15 +13,24 @@ class PhotonHistogram(Experiment, AutoDB):
         nbins = Argument(100)
         repeats = Argument(100)
 
+        cool_f = Parameter(230)
+        detect_f = Parameter(220)
+        detect_t = Parameter(100)
+
+        ion_present = Parameter(True)
+
+        hist = Result()
+        total = Result()
+
     @kernel
     def cool_detect(self):
         with parallel:
             self.bd.pulse(200*MHz, 1*ms)
             self.bdd.pulse(300*MHz, 1*ms)
-        self.bd.pulse(210*MHz, 100*us)
+        self.bd.pulse(self.cool_f*MHz, 100*us)
         with parallel:
-            self.bd.pulse(220*MHz, 100*us)
-            self.pmt.gate_rising(100*us)
+            self.bd.pulse(self.detect_f*MHz, self.detect_t*us)
+            self.pmt.gate_rising(self.detect_t*us)
         self.bd.on(200*MHz)
         self.bdd.on(300*MHz)
         return self.pmt.count()
@@ -29,11 +38,20 @@ class PhotonHistogram(Experiment, AutoDB):
     @kernel
     def run(self):
         hist = [0 for _ in range(self.nbins)]
+        total = 0
 
         for i in range(self.repeats):
             n = self.cool_detect()
             if n >= self.nbins:
                 n = self.nbins - 1
             hist[n] += 1
+            total += n
 
-        print(hist)
+        self.hist = hist
+        self.total = total
+        self.ion_present = total > 5*self.repeats
+
+
+if __name__ == "__main__":
+    from artiq.frontend.artiq_run import run
+    run()