[Jef] [EXTERNAL] eta->pi0gg background from eta->gg, eta->3pi0

[Susan Schadmand]

There might be something useful in the A2 paper, see 
https://urldefense.proofpoint.com/v2/url?u=https-3A__arxiv.org_pdf_1405.4904.pdf&d=DwICaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=JOJ62NEwwkI7R0M2R59fbQ&m=5Y7472olvxXv6Sd2q8sF8W26idKXgIvLAMwmtRvD4Go&s=KfiAGstPDb0aCDfflS4VlAXi4oKW2L-lrTxXtRyBPDk&e= :

contribution to eta->pi0gg from eta->gg decay:

  * due to split offs from both outgoing photons
  * they cut on the smaller values of the two possible invariant masses
    m(pi0gg)
  * (this is a way of cutting on gg opening angles)

contribution to eta->pi0gg from eta->3pi0 decay:

  * showers of some outgoing photons overlap (or are not detected)
  * they cut on an "effective radius" of the clusters to suppress the
    case of overlapping
  * (this is a simple cut on cluster shape)


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/jef/attachments/20210826/8dc8cb14/attachment.html>