RadPhi TechNote
radphi-2001-711

Monte Carlo study of background from $B_1$ reactions



Mihajlo Kornicer
Richard T. Jones
University of Connecticut, Storrs, CT



November 7, 2001

Abstract:

Monte Carlo study shows that major sources of hadronic background in the Radphi experiment are reactions with produced charged particles reconstructed as neutral in the LGD, as well as all-neutral decays of heavier mesons such as $b_1$. The first source of background can be suppressed by requiring large energy deposition in the LGD or by using the CPV. The second one cannot be suppressed by either of these two methods or by energy restrictions in the BGV, until the clusterizing technique is improved. It is found that a large fraction of $b_1 \rightarrow 5\gamma$ decays with all 5 photons in the forward region ($\theta < 25^0$) are reconstructed as 3 or 4 cluster events. This is because soft photons with energy below some threshold (currently about 300 MeV) are not reconstructed. In addition, some fraction of soft photons are merged with a high-energy neighbor.