STAR HardProbes PWG

["Yi Yang" <yiyang429 AT gate.sinica.edu.tw>]

Hi Youqi,

Thanks a lot for the explanation. It is much clearer to me now. I don't have any further comments on it.

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:Youqi Song<youqi.song AT yale.edu>
To:star-hp-l<star-hp-l AT lists.bnl.gov>
Date:  Wed, 18 Sep 2024 20:45:27
Subject: Re: [[Star-hp-l] ] STAR presentation by Youqi Song for HP2024 submitted for review

Hi Yi,

Thanks for the follow-up! To clarify, slide 9 is part of discussion for the pp result. We have at the beginning of the talk that rc is probing string fragmentation, but there’s a caveat that neutral decays also give negative rc, so I am trying to acknowledge this caveat in slide 9. Also in backup slide 23, I have details of what the parents of the leading pions are. 

I don’t think it will affect background subtraction because when we do embedding into isobar events, we use the final state hadrons that are already done with decays. I think the final state hadrons should be consistent between PYTHIA and HERWIG because they have been tuned to data, even though how they get to the final states from resonances could be different.

Best,

Youqi

On Wed, Sep 18, 2024 at 2:43 AM Yi Yang <yiyang429 AT gate.sinica.edu.tw> wrote:

Hi Youqi,

Thanks a lot for the updated version and the reply. It's good to hear that Neil is interested in rc in Au+Au. 

Regarding p.9, thanks a lot for adding this information. I am wondering if the PYTHIA and HERWIG is an almost factor of 2 difference from the neutral resonance, will it affect to your later background subtraction study where you are using PYTHIA? Or this is still just the prove for principle? If so, what is the plan for the future?

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:Youqi Song<youqi.song AT yale.edu>
To:star-hp-l<star-hp-l AT lists.bnl.gov>
Date: Wed, 18 Sep 2024 09:16:14
Subject: Re: [[Star-hp-l] ] STAR presentation by Youqi Song for HP2024 submitted for review

Hi conveners,

I just uploaded a newer version of slides (v3) to drupal after my practice with the local group, and the slide numbers are now different again. In particular, slides 2, 3, 9 and 10 are new.

Below I also rewrote the previous email I sent with the updated slide numbers. Please take a look. Thank you!

Best,

Youqi

Yi:

 - p8: We have lots of Au+Au data, do you expect any difference between Au+Au and Isobar (can we learn more from using Au+Au data)? Probably it would be nice to add a statement here.

Slide 10 in the new version addresses this. I think the lower multiplicity can make background subtraction easier, although if there is modification of hadronization due to QGP, then the signal would probably be more significant in AuAu. And as an internal note, Diptanil expressed interest in measuring r_c with the AuAu dataset before, which is why I went with isobar.

Nihar:

Slide#3:

|η| < 1, full azimuthal coverage -> Mention full eta acceptance of TPC 
|eta| < 1.5
      if this is for your analysis then mention in the dataset and track
selection criteria

I didn't use |eta| < 1.5. I have |eta| < 1 because I see that both Tong and Tristan did their analyses with |eta| < 1 and thought that iTPC wasn't in use in the isobar run.

Slide9:
enhanced S/B -> Please elaborate

This is now on slide 12. Unfortunately, there is already quite a lot of text on this slide, so I would prefer to not put more if it's ok. I said it's an enhanced S/B because with the embedding, I put at least one real jet from PYTHIA into the isobar event. But in the actual data analysis, we cannot guarantee that we have a real jet per event.

On Mon, Sep 16, 2024 at 8:06 PM Youqi Song <youqi.song AT yale.edu> wrote:

Hi all,

Thanks for the comments! I uploaded a new version to drupal. Note that slides 2 and 9 in the current version are new. Please find my responses to your suggestions below. Thank you!

Best,

Youqi

Yi:

 - p8: We have lots of Au+Au data, do you expect any difference between Au+Au and Isobar (can we learn more from using Au+Au data)? Probably it would be nice to add a statement here.

Slide 9 in the new version addresses this. I think the lower multiplicity can make background subtraction easier, although if there is modification of hadronization due to QGP, then the signal would probably be more significant in AuAu. And as an internal note, Diptanil expressed interest in measuring r_c with the AuAu dataset before, which is why I went with isobar.

Nihar:

Slide#3:

|η| < 1, full azimuthal coverage -> Mention full eta acceptance of TPC 
|eta| < 1.5
      if this is for your analysis then mention in the dataset and track
selection criteria

I didn't use |eta| < 1.5. I have |eta| < 1 because I see that both Tong and Tristan did their analyses with |eta| < 1 and thought that iTPC wasn't in use in the isobar run.

Slide9:
enhanced S/B -> Please elaborate

This is now on slide 11. Unfortunately, there is already quite a lot of text on this slide, so I would prefer to not put more if it's ok. I said it's an enhanced S/B because with the embedding, I put at least one real jet from PYTHIA into the isobar event. But in the actual data analysis, we cannot guarantee that we have a real jet per event.

On Mon, Sep 16, 2024 at 8:20 AM Nihar Sahoo <nihar AT rcf.rhic.bnl.gov> wrote:

Hello Youqi,

Please find a few comments on your nice presentation slides.

Slide#3:

|η| < 1, full azimuthal coverage -> Mention full eta acceptance of TPC 
|eta| < 1.5
      if this is for your analysis then mention in the dataset and track
selection criteria

Slide9:
enhanced S/B -> Please elaborate


Best
Nihar

On 2024-09-08 10:39, webmaster AT star.bnl.gov wrote:
> Dear Star-hp-l AT lists.bnl.gov members,
>
> Youqi Song (youqi.song AT yale.edu) has submitted a material for a review,
> please have a look:
> https://drupal.star.bnl.gov/STAR/node/68863
>
> Deadline: 2024-09-22
> ---
> If you have any problems with the review process, please contact
> webmaster AT www.star.bnl.gov