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Re: [[Star-hp-l] ] STAR presentation by Priyanka Roy Chowdhury for Zimanyi School 2024 submitted for review

From: tc88qy <tc88qy AT rcf.rhic.bnl.gov>
To: 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
Date: Fri, 29 Nov 2024 19:21:30 +0800

Hi Priyanka

I am ok with the new version and sign-off. As the meeting is approaching. I will push your talk to next level. You will implements Nihar and Isaacs's further comments in star-talk list.

Qian Yang

On 2024-11-29 16:19, "Roy Chowdhury Priyanka (DOKT)" wrote:

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
[1]

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>

Links:
------
[1] https://drupal.star.bnl.gov/STAR/system/files/Zimanyi_24_Priyanka_V2.pdf

Re: [[Star-hp-l] ] STAR presentation by Priyanka Roy Chowdhury for Zimanyi School 2024 submitted for review , (continued)