Minutes of the GPC (#313) meeting on April 6^th, 2021.

Participants: Barbara, Bill, Carl, Daniel, Shenghui, Qian

Code QA: Qian got the codes from the CVS. At the first look, all pieces of software for various steps are stored and accessible in the CVS. The data files are stored on local discs, while they should be archived in HPSS. Qian run a few macros and they work and produce plots that look like those in the paper draft. Qian will continue with the QA, which may take some time because the analysis is rather complicated (many steps to check).

General comments on the paper:

1. Introduction is difficult to follow and the text needs improvement (correction of grammar mistakes, unification of used tenses etc).

2. The general idea of the measurements and the flow of the analysis are clear, but some details need to be better explained.

Specific questions, comments, and suggestions

1. Is the analysis the same as in the previously published long NPE paper (Phys. Rev. C 95 (2017) 34907) using run 5 and run 8 data?

   1. There are subtle differences: There are subtle differences: this study does not use SMD, and in this paper the contributions from Jpsi, Upsilon, vector mesons and Drell-Yan are subtracted from the NPE yield. Previously they were estimated, but only the contribution from vector mesons was subtracted. So, in order to compare with published result, the result with only subtracting the contribution from vector mesons is also provided in this paper which is shown in Fig.6 of paper draft.

2. Suggestions:

   1. In the introduction, refer to the run 5/run 8 NPE paper and make it clear that the analysis method is (almost) the same, and mention that the goal of this work is to provide high-quality data at high p_T. We may also mention the relative sizes of the data sets used for run 5/run 8 NPE and this study.

   2. Later in the paper, describe and motive differences. Example: this study does not use SMD, because it would reduce efficiency at high p_T, while the potential benefits of SMD (suppression of hadron yield) are not so important – purity is already very good at high p_T.

3. It was not clear from the text which HT trigger configurations are used (one configuration used ToF, which is not mentioned in the text)

   1. Indeed, HT0-BBCMB-TOF0 (HT0 with ToF) was used. Then ToF should be mentioned in the text, where triggers are described.

4. Fig. 4: The first point from the HT2 trigger is below the nominal threshold of that trigger and has low efficiency. There is a possible issue with using this HT2 data (below 4.2 GeV), because it may not be reliable (trigger efficiency is very low). The PAs compared the spectra from both HT0 and HT2 data sets (Fig. 47 on page 60 in the analysis note) and they are consistent. Carl will look into the details and we will decide later whether we use HT0 of HT2 point for 4 <p_T < 4.5 GeV/c.

Todo for the next meeting:

1. Bill will send comments, corrections, and suggestions to the introduction and other general comments to the text.

2. All: please send questions and comments on the analysis and its description by the end of Friday, April 9^th.

3. Qian: please start QA of the analysis software and document the findings (Are the instructions sufficient to run the code? Does the code run and produce the correct output? Are there any missing files?)

We will meet on Tuesday, April 13^th, at 10:30 Eastern Time, and continue the discussion.