diff --git a/.gitignore b/.gitignore
index 0987766..33825e0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,7 @@ JFMC_CuFluoPeak
 JFMC_CuFluoPeakFit
 JFMC_CurrentSourceScan
 JFMC_DirectBeamScan
+dummyRootFileMaker
 
 data/
 plots/
diff --git a/dummyRootFileMaker.cpp b/dummyRootFileMaker.cpp
new file mode 100644
index 0000000..78cc59d
--- /dev/null
+++ b/dummyRootFileMaker.cpp
@@ -0,0 +1,24 @@
+// file to write a dummy results root file, so the calib writer can run even when no data exists
+
+#include "/afs/psi.ch/project/mythen/sophie/sls_detector_calibration/jungfrauCommonHeader.h"
+#include "/afs/psi.ch/project/mythen/sophie/sls_detector_calibration/jungfrauCommonFunctions.h"
+
+#include "TFile.h"
+#include "TH2.h"
+
+int main(int argc, char* argv[]) {
+
+  TH2F* g1overg2map = new TH2F("g1overg2map","",NC,-0.5,NC-0.5,NR,-0.5,NR-0.5);
+  TH2F* g1overg2ermap = new TH2F("g1overg2ermap","",NC,-0.5,NC-0.5,NR,-0.5,NR-0.5);
+
+  for (int i = 0; i < NCH; i++) {
+    g1overg2map->SetBinContent((i%NC)+1,(i/NC)+1,13.0);
+    g1overg2ermap->SetBinContent((i%NC)+1,(i/NC)+1,0.1);
+  }
+
+  TFile* saved_file2 = new TFile("data/M027/CS_ratio_M027.root","RECREATE");
+  g1overg2map->Write();
+  g1overg2ermap->Write();
+  saved_file2->Close();
+
+}
diff --git a/makefile b/makefile
index 4b2a44c..d4f671c 100644
--- a/makefile
+++ b/makefile
@@ -13,3 +13,6 @@ JFMC_CurrentSourceScan: JFMC_CurrentSourceScan.cpp
 
 JFMC_CalibWriter: JFMC_CalibWriter.cpp
 	g++ -Wall -O3 -m64 -I$(ROOTSYS)/include -L$(ROOTSYS)/lib -lGui -lCore -lCint -lRIO -lNet -lHist -lGraf -lGraf3d -lGpad -lTree -lRint -lPostscript -lMatrix -lPhysics -lMathCore -lThread -pthread -lm -ldl -rdynamic JFMC_CalibWriter.cpp -o JFMC_CalibWriter
+
+dummyRootFileMaker: dummyRootFileMaker.cpp
+	g++ -Wall -O3 -m64 -I$(ROOTSYS)/include -L$(ROOTSYS)/lib -lGui -lCore -lCint -lRIO -lNet -lHist -lGraf -lGraf3d -lGpad -lTree -lRint -lPostscript -lMatrix -lPhysics -lMathCore -lThread -pthread -lm -ldl -rdynamic dummyRootFileMaker.cpp -o dummyRootFileMaker
\ No newline at end of file
diff --git a/run_JFModuleCalib_CuFBDCS.txt b/run_JFModuleCalib_CuFBDCS.txt
index 1eca76e..5f4c0dc 100644
--- a/run_JFModuleCalib_CuFBDCS.txt
+++ b/run_JFModuleCalib_CuFBDCS.txt
@@ -36,7 +36,7 @@ Module 022 - 1M	bottom LCLS, PX
 Module 027 - old HDI (no current source scan). sent to ESRF with Paolo
 ./JFMC_CuFluoPeak 027 /data_pool/Module_027_Calib FCu_40kvp_60mA_10us_500Hz_QS_pede FCu_40kvp_60mA_10us_500Hz_QS_beam
 ./JFMC_CuFluoPeakFit 027
-
+./dummyRootFileMaker
 
 Module 040 - partly etched. sent to ESRF with Paolo
 ./JFMC_CuFluoPeak 040 /data_pool/Module_040_Calib Cu_FLuo_240317_500Hz_10us_QS_pede Cu_FLuo_240317_500Hz_10us_QS_beam