diff --git a/src/analyze.cpp b/src/analyze.cpp
index 1a42d19919ef6d368f5faaf7dd5a9175fd633818..22a4da8f59d0d33f842e01e1c4c51e956dc87142 100644
--- a/src/analyze.cpp
+++ b/src/analyze.cpp
@@ -105,14 +105,14 @@ void write_raw_data(const std::string &dpath, const std::string &opath, const st
                 // assign a large enough buffer
                 auto event = new ssp::SSPEvent(10000);
                 m.event = static_cast<void*>(event);
-                tree->Branch(Form("SSP_%d_%d_evt", m.crate, m.slot),        &event->tTrigNum,   "trigNum/I");
-                tree->Branch(Form("SSP_%d_%d_trigtime", m.crate, m.slot),   &event->tTrigTime,  "trigTime/D");
-                tree->Branch(Form("SSP_%d_%d_nedge", m.crate, m.slot),      &event->Nedges,     "N/I");
-                tree->Branch(Form("SSP_%d_%d_ch", m.crate, m.slot),         &event->channel[0], "channel[N]/I");
-                tree->Branch(Form("SSP_%d_%d_pol", m.crate, m.slot),        &event->edge[0],    "edge[N]/I");
-                tree->Branch(Form("SSP_%d_%d_time", m.crate, m.slot),       &event->time[0],    "time[N]/I");
-                tree->Branch(Form("SSP_%d_%d_fiber", m.crate, m.slot),      &event->fiber[0],   "fiber[N]/I");
-                tree->Branch(Form("SSP_%d_%d_slot", m.crate, m.slot),       &event->slot[0],    "slot[N]/I");
+                tree->Branch("SSP_evt"),        &event->tTrigNum,   "evt/I");
+                tree->Branch("SSP_trigtime"),   &event->tTrigTime,  "trigtime/D");
+                tree->Branch("SSP_nedge"),      &event->Nedges,     "nedge/I");
+                tree->Branch("SSP_ch"),         &event->channel[0], "ch[nedge]/I");
+                tree->Branch("SSP_pol"),        &event->edge[0],    "pol[nedge]/I");
+                tree->Branch("SSP_time"),       &event->time[0],    "time[nedge]/I");
+                tree->Branch("SSP_fiber"),      &event->fiber[0],   "fiber[nedge]/I");
+                tree->Branch("SSP_slot"),       &event->slot[0],    "slot[nedge]/I");
             }
             break;
         default: