STAR HardProbes PWG

["Roy Chowdhury Priyanka (DOKT)" <priyanka.roy_chowdhury.dokt AT pw.edu.pl>]

Hi Qian, Isaac, Nihar and all,

Thanks again for your questions and comments.

Firstly, I updated the slides as V3 where I dropped the S19 and 20 in previous version (V2). Explanation is in the below.

I used the approach of fitting all parameters [Re(d0)=0, Im(d0)=0, Re(f0)=value from different theory model, radius(r0)= 0.5 to 10 fm] in LL model to perform a chi2 test. Although I realised that I kept one parameter [Im(f0)] free which should be taken as 0 too in cases where Im(f0) values aren't mentioned in certain theory model. I repeat the chi2 test using Re(f0) values from Guo model but took the spin states separately (f0 has different values for I=3/2 and I=1/2) as I did before (ref slides are attached here which I prepared for CF-PWG meeting on yesterday but due to lack of time I couldn't get a chance of discussion). Thanks to Qian for pointing out the issue of considering fractions of spin states properly. We decided to repeat the test with a consideration of taking spin state fractions. Currently, for model fitting, we considered spin averaged. So, for now I withdraw the slides with this discussion in Zimanyi school.

Another question asked by Qian regarding mentioning the fraction of spin states on the slides. If I understand your question correctly, you want me to describe what fractions were taken during theory predictions for C(k*) calculations. There's a back up slide (S22) where I discussed about fractions of isospin sates for D-pi channels. As the talk duration is 12+3, I still kept it in backup for additional discussion.

I would also like to address Isaac's questions about slides 19 and 20 in (V2) regarding model fitting. For Huang model, I took the unc. as 3-sigma and got the chi2 curve like that. I repeated the calculation considering unc. as 1-sigma and the chi2 curve was similar as others. So, it is still not well understood why. I agree with your comment on S20 (in V2) that I can't draw such conclusion about scattering length based on current statistics, so it is better not to make such statement. Our main goal is to perform model fitting properly to understand a lower limit of source radii.

If these explanations answer your questions, I would like to request to kindly push my contribution to the start-talks.

Regards,

Priyanka

---

From: star-hp-l-request AT lists.bnl.gov <star-hp-l-request AT lists.bnl.gov> on behalf of tc88qy <tc88qy AT rcf.rhic.bnl.gov>
Sent: Thursday, November 28, 2024 4:21 AM
To: star-hp-l AT lists.bnl.gov <star-hp-l AT lists.bnl.gov>
Cc: Mooney, Isaac <isaac.mooney AT yale.edu>
Subject: Re: [[Star-hp-l] ] STAR presentation by Priyanka Roy Chowdhury for Zimanyi School 2024 submitted for review

 

Hi Priyanka,

  As shown in equation 1 on your slides. The correlation functions is an
average of different pair spin state. And it is very important in
extraction interaction and source parameters. D0 is a scalar meson, Kaon
and pion are pseduonscalar mesons. But Proton is a fermion. There is
only on spin state for D0-Kaon/Pion, but the spin stat for D0-proton
pair is different. Mentioning the spin state will make the talk more
clear to me. But I will let the speaker decide if she wants to include
it or not.

Qian Yang


On 2024-11-27 19:20, "Roy Chowdhury Priyanka (DOKT)" wrote:
> Hi Qian and all,
>
>  Please accept my apologies for the delay. I finished the model study
> for D-pi pairs. I used Lednicky-Lubositsz formalism and fixed
> interaction parameters (f0, R) according to theory models (used by
> ALICE) to perform chi2/ndf vs radius test. I attached a comparison
> plot of chi2/ndf vs R on S19. As we can see the chi2 minimum is around
> R = 2 fm (varies with different model), so the lower limit of source
> radii is around 2 fm but we can't pin down the upper limit of the
> source radii from current statistics.
>  On S20, I added fit plots while source radii are fixed by 2fm, 3 fm
> and so on which are providing the scattering length around 0 fm.
>  Please let me know if you have any questions and comments. My plan is
> to discuss the fit results with my supervisor as well as with CF-PWG's
> tomorrow meeting. For the time restriction, I updated my slides (V2)
> with the above-mentioned plots.
>
>  On S13, the second bullet (regarding D0 background) has been removed
> to avoid any confusion.
>
>  Conclusion statement of physics fig plots has been modified based on
> Nihar's comment.
>
>  I am still not sure how to address the spin state of considered
> pairs, so didn't mention anything about spin states.
>
> 
> https://drupal.star.bnl.gov/STAR/system/files/Zimanyi_24_Priyanka_V2.pdf
>
>
>  Regards,
>  Priyanka
>
> -------------------------
>
> From: star-hp-l-request AT lists.bnl.gov
> <star-hp-l-request AT lists.bnl.gov> on behalf of tc88qy
> <tc88qy AT rcf.rhic.bnl.gov>
> Sent: Friday, November 22, 2024 2:43 PM
> To: star-hp-l AT lists.bnl.gov <star-hp-l AT lists.bnl.gov>
> Cc: Mooney, Isaac <isaac.mooney AT yale.edu>
> Subject: Re: [[Star-hp-l] ] STAR presentation by Priyanka Roy
> Chowdhury for Zimanyi School 2024 submitted for review
>
> Hello Priyanka
>
>    Please find my comments below.
> 1) if you do not used consider the combinatorial background
> separately,
> then it is no need to mention in Like-sing and mixed-event.
> 2) For the physics plots, it is ok of considering spin average. But I
> think you should make it clear. Just like the plots you sent out,
> different isospin assumptions gives different shape. Then how the
> model
> deal with it?
>
> Qian Yang
>
> On 2024-11-22 00:39, Mooney, Isaac wrote:
>> Hi Nihar, I’m fine with your phrasing. Priyanka, thanks for
> sending
>> the additional studies. I’m happy with the slides pending the
>> placeholder, so we’ll wait until you send that in a couple of
> days.
>>
>> Thanks,
>> Isaac
>>
>>> On Nov 21, 2024, at 09:52, Roy Chowdhury Priyanka (DOKT)
>>> <star-hp-l AT lists.bnl.gov> wrote:
>>>
>>> Dear all,
>>>
>>> Many thanks for all your comments, questions and suggestions. Sorry
>>> for my delay in getting back to you. I was going through required
>>> tests for fitting my data. I have uploaded a modified version and
>>> attached two slides to clarify my answers. Please find my answers
> to
>>> your questions in the following.
>>>
>>> Nihar:
>>> Slide 2: Please provide reference of this cartoon -> added
>>>
>>> Slide 16 & 17: I agree with Isaac's explanation about the
>>> conclusion statements. Please check the attached slides also, where
>>> I have shown example fits for D0-pi data using Ledniszky-Lubositz
>>> model. I fixed scattering length [Re(f0)] using different theory
>>> model (showing plots using one model with two Isospin states only)
>>> and took variation in source radii (R) to perform chi2 test. This
>>> study could only help us to understand the lower limit of source
>>> radii which agrees with our already made conclusion. As we don't
>>> have any model prediction using R > 5 fm, it's not possible to
>>> compare data with predictions with higher radii. In general, as we
>>> know, larger the source radii, flatter the correlation signal. As
> we
>>> have flat signal with large uncertainties, our fitting and chi2
> test
>>> could only help us to exclude the range of R below which chi2 test
>>> fails.
>>>
>>> Slide 18: C(k*) signal is flat within large uncertainties at the
>>> low k* bin.
>>>
>>> Slide 19: Some fit plots are ready, need to finish for other pairs
>>> (D0-K, D0-p). It should take one-two days. If that's okay, I would
>>> still like to keep the slide on hold.
>>>
>>> Qian:
>>> Slide 4, Please give a reference to this page -> Done
>>> Slide 6, it is sqrt(pi) rather than sort(2) in equation (1) ->
>>> Corrected
>>> Slide 12, If your analysis just used part of the data, then you
>>> should mention it -> I mentioned the no. of good events analysed
>>> (490 M), do you want me to put it as a % of whole dataset?
>>> Slide 13, Background is not shown in the plot (either SE-LS or
>>> MX-UL) -> In our analysis, we didn't consider the combinatorial
>>> background separately, rather used the fitting approach over all D0
>>> candidates
>>> Slide 16,17 and 18, It will be good to point out how you deal with
>>> different spin states and its relative fraction -> I am not sure
>>> about how to consider the spin states (in general we consider spin
>>> average). Do you have any suggestion on this?
>>>
>>> I am open for any further discussion, even at today's PWG meeting.
>>>
>>> Regards,
>>> Priyanka
>>>
>>> -------------------------
>>>
>>> From: star-hp-l-request AT lists.bnl.gov
>>> <star-hp-l-request AT lists.bnl.gov> on behalf of Nihar Sahoo
>>> <nihar AT rcf.rhic.bnl.gov>
>>> Sent: Thursday, November 21, 2024 5:18 AM
>>> To: Mooney, Isaac <isaac.mooney AT yale.edu>
>>> Cc: star-hp-l AT lists.bnl.gov <star-hp-l AT lists.bnl.gov>
>>> Subject: Re: [[Star-hp-l] ] STAR presentation by Priyanka Roy
>>> Chowdhury for Zimanyi School 2024 submitted for review
>>>
>>> Hello Isaac and Priyanka,
>>>
>>> On Slide16: we could rephrase that bottom sentence as
>>> "STAR data shows no significant correlations, but the data
>>> consistent
>>> with theoretical model
>>> prediction with emission source size of 5 fm within uncertainty"
>>>
>>> What do you think?
>>>
>>> Best
>>> Nihar
>>>
>>> On 2024-11-21 03:10, Mooney, Isaac wrote:
>>>> Hi Priyanka,
>>>>
>>>> I have no additional comments on your nice slides, pending the
>>>> possible addition on slide 19. One comment to Nihar: on s. 16, I
>>> would
>>>> call that consistency between the model (pink) and data across the
>>>> entire domain, within statistical and systematic uncertainty of
>>> the
>>>> data and theoretical uncertainty on the model. By eye it looks
>>> like <
>>>> 1 sigma deviation of the central value from the model value in the
>>>> lowest k* bin. Maybe the deviation when combining both of the
>>> lowest
>>>> two bins gets above 1*sigma, but since the lowest bin is where the
>>>> qualitative behavior of the model is changing, it seems that would
>>> be
>>>> the region where we want to know the consistency or lack thereof.
>>>> Priyanka could comment if she has the exact numbers for deviations
>>> of
>>>> the data and model as a whole with all bins, and/or just with the
>>>> lowest two where there may be some slight tension, and/or the
>>> value
>>>> for the very lowest bin. But to me it seems that what she is
>>> trying to
>>>> say is: "yes the data are flat, but within uncertainty, do they
>>> also
>>>> support a physical picture which has some effect at low k*? Yes."
>>> And
>>>> I think that’s a valid interpretation, given the plot.
>>>>
>>>> Thanks,
>>>> Isaac
>>>>
>>>>> On Nov 18, 2024, at 22:33, tc88qy <tc88qy AT rcf.rhic.bnl.gov>
>>> wrote:
>>>>> Hello Priyanka,
>>>>>
>>>>> Nice Slides. Additional to Nihar's comments, please find my
>>> comments
>>>>> below:
>>>>> Slide 4, Please give a reference to this page.
>>>>> Slide 6, it is sqrt(pi) rather than sort(2) in equation (1).
>>>>> Slide 12, If your analysis just used part of the data, then you
>>>>> should mention it.
>>>>> Slide 13, Background is not shown in the plot (either SE-LS or
>>>>> MX-UL)
>>>>> Slide 16,17 and 18, It will be good to point out how you deal
>>> with
>>>>> different spin states and its relative fraction.
>>>>>
>>>>> Qian Yang
>>>>>
>>>>> On 2024-11-18 13:14, Nihar Sahoo wrote:
>>>>> Hello Priyanka,
>>>>> Please find my comments on your nice slides.
>>>>> _Slide2: Please provide reference of this cartoon [ALICE
>>>>> experiment’s probably]
>>>>> _Slide16, “STAR data shows no significant correlations, but the
>>>>> data
>>>>> is also consistent with theoretical model
>>>>> predictions with emission source size of 5 fm or larger” -> It
>>> is
>>>>> not
>>>>> correct. It is not consistent at low k*. Please correct it.
>>>>> _Similarly in Slide 17, It is consistent within uncertainty at
>>> low
>>>>> k*.
>>>>> Please clearly mention it.
>>>>> _Slid18:  “We do not observe significant correlations between
>>> D0-p
>>>>> pairs” -> on “Significant correlation”, who do you know
>>> this
>>>>> is not
>>>>> significant? I think at low k* we see some correlation., but you
>>>>> have
>>>>> larger bin size so last point only shows this correlation. Is not
>>>>> it?
>>>>> _Slide19:  Either you drop this slide with “place holder” or
>>> you
>>>>> finalise this slide  before we sign off.
>>>>> Best
>>>>> Nihar
>>>>> On 2024-11-18 02:50, "Roy Chowdhury Priyanka (DOKT)" wrote:
>>>>> Dear all,
>>>>> Please have a look at the submitted slides for the upcoming
>>> Zimanyi
>>>>> school. Slides are almost similar as WPCF with a place holder in
>>>>> slide
>>>>> no. 19, which should be finalized soon.
>>>>> Regards,
>>>>> Priyanka
>>>>> -------------------------
>>>>> From: star-hp-l-request AT lists.bnl.gov
>>>>> <star-hp-l-request AT lists.bnl.gov> on behalf of
>>>>> webmaster AT star.bnl.gov
>>>>> <webmaster AT star.bnl.gov>
>>>>> Sent: Sunday, November 17, 2024 10:15 PM
>>>>> To: Star-hp-l AT lists.bnl.gov <Star-hp-l AT lists.bnl.gov>
>>>>> Subject: [[Star-hp-l] ] STAR presentation by Priyanka Roy
>>> Chowdhury
>>>>> for Zimanyi School 2024 submitted for review
>>>>> Dear Star-hp-l AT lists.bnl.gov members,
>>>>> Priyanka Roy Chowdhury (priyanka.roy_chowdhury.dokt AT pw.edu.pl)
>>> has
>>>>> submitted
>>>>> a material for a review, please have a look:
>>>>>
>>>> https://drupal.star.bnl.gov/STAR/node/69916
>>>>> [1]
>>>>> Deadline: 2024-12-02
>>>>> ---
>>>>> If you have any problems with the review process, please contact
>>>>>
>>>> webmaster@http://www.star.bnl.gov/
>>>>> [2]
>>>>
>>>>
>>>>
>>>> Links:
>>>> ------
>>>> [1] https://drupal.star.bnl.gov/STAR/node/69916
>>>> [2] http://www.star.bnl.gov/
>>>
>>> <Chi2 test_D0-pi_Nov 21_Priyanka.pdf>

Attachment: CF PWG Nov 28_Priyanka.pdf
Description: CF PWG Nov 28_Priyanka.pdf