STAR HardProbes PWG

[Barbara Trzeciak <barbara.trzeciak AT gmail.com>]

Hi Qian,

thanks for the updates, the slides look good to me.

Just last comments. 

- There were suggestions to have a comparison of isobar results in fine binning (not the pT integrated one) in 0-80% centrality to the Au+Au results at the same centrality.  You can add the Au+Au on slide 14 or 16.

- s15: improvement of precision is not so clear to me for high pT. The blue point seems to have actually larger uncertainty than the Au+Au point, and the blue result is in a wider pT range. Also, there is no legend for the blue point.

And that's also another reason I think it's better to have a comparison of Au+Au and isobar with the original isobar binning. You say on this slide we have better precision now, but the shown isobar points are in wide bins, which of course reduces the uncertainties. 

- s16: that affecting -> that affects

- s17:  no obvious system size and energy dependence -> no significant collision system and energy dependence at the same <N_part>

- s17: effect dominated -> effect dominates

And regarding your question. What we agreed during meetings before, when we discussed the non-flow estimation, is that at high pT the uncertainties are anyway large and the non-flow will not change the conclusions of zero v2. So we prioritized finalizing other parts of the analysis. 

For the publication, the non-flow effect will be estimated. 

Cheers,

Barbara

On Thu, Jun 9, 2022 at 2:37 PM tc88qy via Star-hp-l <star-hp-l AT lists.bnl.gov> wrote:

Hi all
   Please find the new version in the same link(v5).
    As Barbara suggested it would be good that Yu-ming can prepare some
materials for TPC event-plane method in slide 13.
    Please provide me the systematic uncertainties in slide 14
(20-60%)and 15 (pT-integral) ASAP.

   I have a concern about the TPC method. We currently do not estimate
the non-flow contribution, which could be a main source for high-pT
J/psi especially for a small system.
Comparing to Au+Au with similar N_part, the non-flow is about 0.2 for
J/psi. If I was asked  about the non-flow contribution during the
meeting. How do we reply? we should have a strategy now.

  For other comments please find inline.
  Also to remind you, my talk is June 14, which is 5 days to go. So
please send out your comments ASAP.

  Yi please find my reply inline below.
Qian Yang


On 2022-06-09 14:55, Yi Yang wrote:
> Hi Qian,
>
> Thanks a lot for the updated version.
>
> I have some comments/suggestions for your consideration:
>   - p3: (top part) you should mention that "early creation" and "long
> lifetime" can lead you to understand the QGP evolution, otherwise
> these two pullets seem to have no connection.
>           (bottom part) Make them larger? And highlight v2 with
> different colors?
done
>   - p5: In the previous page (p4), you compare LHC and RHIC, I would
> think that it would be better if you could compare the v2 from LHC
> here again and mention what we can learn more than LHC.
>           (I understand that you want to emphasize the systema size on
> this page, but it seems more natural compared to the LHC's results.)

>   - p6: minimum bias + high tower
>           But the EPD has worse event plane resolution, right? Should
> we mention it? Probably you can mention it orally.
done
>   - p7: identification --> Identification   (two places)
>           You should add a description on "EPD ', like the other three
> subdetecctors.
done
>  -  p8: More differential measurements
done
>  -  p9 and p10: I would put "central" and "peripheral" in the title to
> make it clear.
done
>  - p10: you have the cartoons for collisions, can you add them in here
> as well?
done
>  - p13: Yu-Ming also has a very nice J/psi mass plot, can you add one
> of them in this page?
>  - p14: I remember what we discussed on the right-handed plot is using
> 20 - 60% for both SP and EP from isobar (like the left-handed one),
> right?
>             (Yu-Ming is working on this plot now.)
>           Second bullet: I am not sure I can get "Significant non-flow
> suppression by using scalar-product method" from the plot (I assume
> you are talking about the right-handed one). Since you might change
> the right-handed plot, you might consider restating this bullet.
>           (By the way, I thought it is "known" that using the non-flow
> contribution will be smaller using scalar-product method, right?)

>  - p15: I would suggest using the pT dependent plot for isobar (the
> right-handed plot on p14), and please add the HT result here.
>            - Most precise v2 measurement
>            - It would be good to make the v2 = 0.003 +/- 0.017 +/-
> 0.010 in one line
We are comparing a result with zero. Then what we want to answer is a
question of yes or no. I think it would be more suitable to give
audience an idea of our final conclusion.

>  - p16: Adding J/psi v2 from LHC in the right-handed plot?
The reason I did not put LHC v2 result is that this is a short talk. It
will be good to more focus on our physics picture. RAA and v2 at RHIC
alone is already fruitful for this talk.
>  - p17: Should mention RAA first (this is the order of your
> presentation).
>             Any remarks from comparing the RHIC and LHC results?
>
> Cheers,
> Yi
>
> On Wed, Jun 8, 2022 at 7:07 PM tc88qy via Star-hp-l
> <star-hp-l AT lists.bnl.gov> wrote:
>
>> Hi Barbara and all
>>
>> After a local STAR group rehearsal, I updated the new version in
>> the
>> same link (v4)
>> Please send out your comments. Thanks
>>
>> Qian Yang
>>
>> On 2022-06-05 09:50, tc88qy via Star-hp-l wrote:
>>> Hi Barbara
>>>
>>> Thanks for your suggestion, Please find my rely inline. and new
>>> version of slides are in the same link
>>>
>>>
>>> Qian Yang
>>>
>>> On 2022-06-04 16:37, Barbara Trzeciak wrote:
>>>> Hi Qian,
>>>>
>>>> thanks for the update. The slides are very nice, please find my
>>>> comments below.
>>>>
>>>> Cheers,
>>>> Barbara
>>>>
>>>> s3 - I would also mention CNM effects
>>> Here I want to more focus on the hot medium effect. so I did not
>>> mention CNM.
>>>
>>>> s4 -  How it affect ->  How is it affected
>>> done
>>>> s5 - w be established -> evolves (?)
>>> done
>>>> s6 - v2 -> v_2
>>> done
>>>> s8 - make the left plot larger
>>> done
>>>> s9- dependence were shown -> dependence is observed
>>> done
>>>> s11 - you can emphasise here precision of the isobar measurement
>>> done
>>>> s13 - it would be good to have better quality plots here. Maybe
>>>> Yu-Ming can prepare example procedure figures with better
>> graphics.
>>>> Also, are these efficiency weighed, is there some physics one can
>>>> extract ?
>>> Sure, It will be good that Yu-Ming can prepare one page of slides
>> for
>>> the procedure.
>>> The graphic is from Yu-Ming's preliminary request slides, I think
>> it
>>> is efficiency weighted.
>>>
>>>> s14 - I think it makes more sense to compare 0-80% isobar to
>> 0-80%
>>>> Au+Au - so to have the Au+Au results on the left plot. But let's
>> also
>>>> see what others think and we can then decide on the final version
>> of
>>>> these plots.
>>>> Also, for the 20-60% range please keep in mind that Yu-Ming might
>> have
>>>> his HT results early next week - in this case please update the
>> plot.
>>>> s15 - since we have higher pT results it would be nice to have
>> here
>>>> also the integrated v2 for higher pT > 4 GeV/c from the HT.
>>>
>>> ok
>>>
>>>> s15 - it's not so obvious to me how much better precision we have
>> in
>>>> isobar compared to Au+Au. Is it possible to combine Au+Au for pT
>> < 4
>>>> GeV/c ? Also, I think it would be better not to combine stat. and
>> sys.
>>>> uncertainties for Au+Au results (also for the other comparison),
>> it
>>>> might show better statistical differences between the two
>> results.
>>>
>>> The combination is not just combine the final physics data point,
>> But
>>> do the extraction from the beginning.
>>> and the stat. and sys. are all needs re-calculation.
>>> I did not put sys. uncertainties for the Au+Au results, the error
>> bars
>>> are just stat. uncertainties.
>>> But the sys. uncertainties is small for Au+Au.
>>>
>>>> s15 - for low pT, i.e. ~< 1 GeV/c, we expect 0 v2 because of the
>> mass
>>>> effect. If it's fast, can you calculate integrated v2 for pT > 1
>> GeV/c
>>>> ?
>>> I need to do some change to have this results. Let's us see, If I
>> can
>>> have the final results next week.
>>>>
>>>> On Fri, Jun 3, 2022 at 8:54 AM tc88qy via Star-hf-l
>>>> <star-hf-l AT lists.bnl.gov> wrote:
>>>>
>>>>> Hello All
>>>>>
>>>>> As we discussed in yesterday's HP meeting. I have updated the
>>>>> slides to
>>>>> a new version.
>>>>> Please find in the same link. Your comments and suggestion are
>>>>> welcome.
>>>>>
>>>>> Qian Yang
>>>>>
>>>>> On 2022-05-31 19:27, webmaster--- via Star-hf-l wrote:
>>>>>> Dear star-hf-l AT lists.bnl.gov members,
>>>>>>
>>>>>> Qian Yang (qianyangstar AT gmail.com) has submitted a material for
>> a
>>>>>> review,
>>>>>> please have a look:
>>>>>> https://drupal.star.bnl.gov/STAR/node/59787
>>>>>>
>>>>>> ---
>>>>>> If you have any problems with the review process, please
>> contact
>>>>>> webmaster AT www.star.bnl.gov
>>>>>> _______________________________________________
>>>>>> Star-hf-l mailing list
>>>>>> Star-hf-l AT lists.bnl.gov
>>>>>> https://lists.bnl.gov/mailman/listinfo/star-hf-l
>>>>> _______________________________________________
>>>>> Star-hf-l mailing list
>>>>> Star-hf-l AT lists.bnl.gov
>>>>> https://lists.bnl.gov/mailman/listinfo/star-hf-l
>>> _______________________________________________
>>> Star-hp-l mailing list
>>> Star-hp-l AT lists.bnl.gov
>>> https://lists.bnl.gov/mailman/listinfo/star-hp-l
>> _______________________________________________
>> Star-hp-l mailing list
>> Star-hp-l AT lists.bnl.gov
>> https://lists.bnl.gov/mailman/listinfo/star-hp-l
_______________________________________________
Star-hp-l mailing list
Star-hp-l AT lists.bnl.gov
https://lists.bnl.gov/mailman/listinfo/star-hp-l