How is the phase space scale factor extracted in FSU ?

Step 1) get the bound necleon data from the butanol and carbon data

• The blue part of the lower missing mass plot is the bound necleon data.

from butanol data	from carbon data

• The x-axis is the π+ azimuthal angle in the rest fram of the π+ π- system
• The y-axis is the center-of-mass energy, W

Step 2) find the ratio between the butanol and carbon data

• The scale factor means the ratio between the bound necleon data of the butanol and carbon data
• The scale factor is extracted to divide the butanol data by the carbon data, shown in the lower-left plot.
• The lower-right plot is made by the projection of the lower-left plot.
• The π+ angle dependence is existed in the scale factor.

butanol/carbon data

Step 3) find the scale factor in each WBin and each φ angle by the projection

• As the scale factor per each energy is needed, it is found from the fitting of a linear equation

Step 4) find the scale factor in each WBin by the fitting