Difference between revisions of "May 10, 2019 - PrimEx-Eta Meeting"

Revision as of 09:40, 17 May 2019

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Drew showed some plots (see slides) showing the motivations for the cuts and vetos used in selecting eta -> 2gamma events, as well as highlighting some issues that will need to be studied in detail at a later point.
- These plots were all made using the default calibration constants with a time stamp from the middle of April, so they don't have any updates to the timing or energy calibrations applied.
- It would good to ask Sean to attend one of the meetings in the future to give a detailed explanation as to how the fcal and rf timing is calculated.
- Ilya pointed out that we will likely need to study each channel of the hadronic background individually with simulations.
- For some reason, subtracting accidentals reduced the eta yields consistently over all angular bins. This likely indicates an issue with the fitting that needs to be corrected.
Compton Yields
- uncertainty below 2% over run periods over a week or so
- There is a several percent shift
Overview of Ilya's physics talk at the collaboration meeting:
- what is primexd, statistics
- mention compton on different targets
- dNdTheta, constrained mass, elasticity
- Future Plans:
  - analyze data
  - ask for second run

@@ Line 21: / Line 21: @@
 #* It would good to ask Sean to attend one of the meetings in the future to give a detailed explanation as to how the fcal and rf timing is calculated.
 #* Ilya pointed out that we will likely need to study each channel of the hadronic background individually with simulations.
+#* For some reason, subtracting accidentals reduced the eta yields consistently over all angular bins. This likely indicates an issue with the fitting that needs to be corrected.
 # Compton Yields
 #* uncertainty below 2% over run periods over a week or so