diff --git a/benchmarks/rich/src/CherenkovPIDAnalysis.cc b/benchmarks/rich/src/CherenkovPIDAnalysis.cc
index ede471cd1545f1f4424b1703e348cb7afc401034..f0f305139a315ddb73c132fdf7a44ec72a08beed 100644
--- a/benchmarks/rich/src/CherenkovPIDAnalysis.cc
+++ b/benchmarks/rich/src/CherenkovPIDAnalysis.cc
@@ -47,7 +47,7 @@ namespace benchmarks {
         );
     m_speTheta_dist = new TH1D(
       "speTheta_dist_"+m_rad_name_trun,
-      "Reconstructed Photon SPE #theta for" +m_rad_title+";#theta[mrad]",
+      "Reconstructed Photon SPE #theta for "+m_rad_title+";#theta[mrad]",
       Tools::theta_bins, 0, Tools::theta_max
     );