frost: status of g p -> k + l analysis
DESCRIPTION
Liam Casey Catholic University of America Adviser: Dr. Franz Klein. FROST: Status of g p -> K + L analysis. Particle Identification. Protons, pions, and kaons are identified by beta and momentum cuts. Kaon region may overlap with misidentified protons and pions. - PowerPoint PPT PresentationTRANSCRIPT
FROST: Status of p -> K+analysis
Liam Casey
Catholic University of America
Adviser: Dr. Franz Klein
Particle Identification● Protons, pions, and kaons are
identified by beta and
momentum cuts.
● Kaon region may overlap
with misidentified protons
and pions.
● Bad timing information may
also give false kaon
identification at low
momentum.
Missing Mass Plots: Finding
Missing Mass Plots: Finding (cont)
Momentum plotted against Missing Mass (1)
●In the lower energy regions, a signal is visible when missing mass is plotted.
●There is additionally a peculiar sloping line passing through the signal region, which most likely indicates misidentified kaons.
Momentum plotted against Missing Mass (2)
●The signal fades for higher photon energies, while the sloping line remains.
Polarization Observable E: Comparison to Model Predictions (2.478 GeV Beam)
●Appears to show some level of agreement with SAID data.
●Higher cos bins are more suspect due to high background contamination.
●For full asymmetry, Ptarg
~ 0.8, Pel
~ 0.85 are taken as averages.
Polarization Observable E: More Energy ranges (2.478 GeV Beam)
Conclusions and Further Work
● All results are extremely preliminary, but first measurements of E
indicate some qualitative agreement with SAID PWA in more
trustworthy regions (those not dominated by heavy background).
● Energy loss corrections need to be added without losing all the
lambdas.
● Background subtraction
● Measurements of other polarization observables