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# System prepended metadata

title: 'Will:'

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# Will:
Janice et al. --

  After reading more of the old discussion, I see that the
suggestion was to remove B decays through MC (sorry I should have
remembered more clearly), etc. ... see:

bn1532_ml:0024

and the motivation question re: on-resonance is also discussed in:

bn1532_ml:0021

were among the reasons to limit the ICHEP presentation. For the
journal article, one needs to examine what can be reasonably added
to those main results, how best to obtain them and what a draft paper strategy would look like.
                                       Thanks,
                                                -- Will j.
                                                

# Draft the Reply

Dear Will, 

Thanks for your clarifying the discussion and logic.

Let me further retrieve pass discussions a bit:

+ In the Belle Note we haven't make it clear the motivation of our measurements -- we entangle the motivation for measurements on continuum & on-resonance, but they should have been targeted separatedly.
(That is basically my fault that my knowledge towards fragmentation is limited, and I'm not that clear on the whole picture then.)

    Thanks for Ralf firstly pointing out this firstly in bn1532_ml:0021:
    > There are many things that are still quite unclear to me and several statements seem to be incorrect. ... Concerning your statements about B hadronization, there is no b fragmentation at these energies and any B mesons are just created via the Upsilon resonances. The decays of those and of the resulting B mesons are about the best understood ones at Belle, such that your statements about improving the B hadronization process using your results does not make sense. As they are decays and not from fragmentation, they are governed not by Pythia but the precise decay tables in EvtGen. Also, because they are so well understood, I do not understand, why you do not remove B decays entirely based on the MC.

  Aferwards, we have discussed internally, and define the purpose of the measurement in a better manner:
  
  (0. The original intention is just a measurement on a never-explored dataset always deserves it in the experiment point of view.)
  1. Off-resonance dataset: understand fragmentation
  2. On-resonance dataset: A better understanding on Data/MC (EvtGen) difference
      1. Inclusive measurement: multiple final-state decays are not precisely modelled, not all processes are encoded 
      2. Angular distributions (polarizations) simulations of baryonic decays are not perfect

+ To remove B-decays out of on-resonance sample and to measure with entire on-resonance sample actually serve different purposes. To be frank, our continnum sample (31.5 fb-1) is relatively large c.f. most of two-particle correlation measurements (µb-1 ~ pb-1), we don't think it is profitable to use the on-resonance dataset as the increments in statistics. However, if the measurement of on-resonance sample itself can provide extra insights to EvtGen, that can be beneficial.


Best ...

# Discussion thread:
+ bn1532_ml:0021) Ralf: 
    (1) Incorrect in motivation: no fragmentation in resonance decays.
    (2) Suggest remove B decays.
+ bn1532_ml:0024) Janice: 
    (1) In terms of experiment, on-resonance sample is not ever measured
    (2) We can use Off-resonance sample to understand fragmentation
    + Extra effort for B-veto, trade-off btw purity/efficiency
+ bn1532_ml:0025) Ralf: 
    + B-veto is a sophisticated method
    + Upsilon decays are background and even mimic a signal
+ bn1532_ml:0028) Janice:
    + B-veto could serve as a good proposal that we can disentangle BB and qq contribution.
    + On-resonance results provide additional understanding for EvtGen simulation: multiple final-state decays, not all processes are encoded ...
+ bn1532_ml:0033) Committee meeting: https://www.dropbox.com/s/0r98dqxdb5p0g88/TwoParticleCorrelation_20200717_CommitteeDiscussion_minutes.pdf?dl=0
    + Focus on off-resonance for ICHEP
    + (in the meeting, not documented) 
    It is known that EvtGen has its disadvantage in describing precisely the angular distributions (polarizations) of three-body baryonic decays; two-particle correlation measurement on on-resonance sample can detect the effect of Data/MC discrepancy.
    + We can include the on-resonance sample in a comprehensive version of journal paper.