STAR HardProbes PWG

["Mooney, Isaac" <isaac.mooney AT yale.edu>]

Hi Nihar,

With Hard Probes coming up I only had time to focus on a few key points in 
the analysis note mostly related to follow-ups from the email chain we had, 
so I’ll provide more comments once the paper moves into the GPC. See below 
for some points of clarification.

Given that Yi has signed off, I will request GPC formation now, with the 
assumption that the uncertainties on the weights will be added sometime soon.

Thanks,
Isaac

Fig. 24. In the text it seems to indicate that the prior variation 
uncertainty is not included in this plot. But to my eye it looks identical to 
the plot from the email chain from July 25. Is the prior uncertainty such a 
small contribution relative to the other uncertainties in this set? I would 
naively have thought it would be sizable. I checked Ref. 4 and 5, and in 5 
(the link is slightly broken by the way), it looks that at a few pTs (~5 and 
~10 GeV for R = 0.2 jets) that the Levy prior variation is among the dominant 
uncertainties. Not sure if that's the case for R = 0.5 here as well. It would 
be helpful, although not necessary to move to GPC, if you could break down 
the uncertainties by source for a representative bin. I.e. Table 7, but with 
a single row of values, and with Uncorrelated and Correlated columns each 
broken up into regularization parameter, method, fME, prior; etc.

It seems likely given Ref. 2 Sec. 13, but Nihar could you clarify that it is 
indeed the background-smeared distribution that is used in the closure test, 
as Peter said in his email? I didn't see a definitive statement in the 
analysis note (feel free to also point me to a line number if I missed it).

One last question about the closure test: are the input and the response 
matrix (and/or the truth) statistically independent? I.e. do you unfold 
population A with response B, or response A? I didn't catch a mention of this 
in Ref. 2 or in the analysis note, but again please let me know if I missed 
it somewhere.

> On Aug 20, 2024, at 02:40, Yi Yang <yiyang429 AT gate.sinica.edu.tw> wrote:
>
> Hi Nihar,
>
> Thanks a lot for the updated version.
> As we discussed privately, I am still a bit concerned about the closure 
> test and I understand what you said that the closure will be difficult in 
> Au+Au. But I still think PAs should understand this better.
> Also, the delta_phi re-weight part in the analysis note is still empty, and 
> you claim it will be small and mentioned that you can finish it in 2 weeks.
>
> Since the analysis has been in the PWG preview for a while, I agree to move 
> forward but I would strongly recommend that you present the updates in the 
> PWG meeting so other PWG members can comment on the rest part.
>
> Cheers,
> Yi
>
> +++++++++++++++++++++++++++++++++++++++++++++++++++
> Yi Yang, Research Fellow
> Institute of Physics, Academia Sinica
> E-Mail: yiyang429 AT gate.sinica.edu.tw
> Tel: +886-2-2789-6709
> +++++++++++++++++++++++++++++++++++++++++++++++++++
>
> -----Original message-----
> From:Nihar Sahoo <nihar AT rcf.rhic.bnl.gov>
> To:Yi Yang <yiyang0429 AT gmail.com>
> Cc:STAR HardProbes PWG <star-hp-l AT lists.bnl.gov>
> Date:Thu, 15 Aug 2024 15:46:57
> Subject:Re: [[Star-hp-l] ] [Star-hp-l] STAR jet acoplanarity paper draft; 
> request to form GPC
>
> Hello All,
>
> Thank you for your comments.
> We have worked on your comment and suggestion.
>
> Please find updated paper draft:
> https://drupal.star.bnl.gov/STAR/system/files/AcoplanarityPaper_v3.pdf
>
> Updated AN:
> https://drupal.star.bnl.gov/STAR/system/files/AcoplanarityAanalysisNote_V3.pdf
>
> And webpage:
> https://drupal.star.bnl.gov/STAR/blog/nihar/Paper-webpage-Measurement-direct-photonjet-and-pi0jet-azimuthal-correlation-AuAu-and-pp-c
>
>
> Thank you
> Nihar for PAs (Derek, Saskia, and Peter)