Prompt Backgrounds

• Radiative pion capture

• ¼{ + N → ° + N´ + ... ⇒ ° → e+ + e{

• Beam electrons

• e{ scattering off a muon stopping target

• Muon decay in flight

• ¹ decays in flight producing e{

• Pion decay in flight

• ¼{ decays in flight producing e{

• Neutron induced backgrounds

• neutrons hit material producing e{