STAR HardProbes PWG

[Nihar Sahoo <nihar AT rcf.rhic.bnl.gov>]

Hello Youqi,

we have requested for PWGC review of your nice work.
You will hear soon from Rongrong the detailed information.
Please prepare a presentation for this PWGC review.

Thank you
Nihar

On 2023-03-10 22:19, Nihar Sahoo wrote:
> Hi Youqi,
>
> 2D plot doesn’t present the results very well as you can see in the
> projection plot. I would suggest to add these two plots as two panels
> of Fig2.
>
> > would agree that from slide 35, we see that dM=0 jets have on average
> > a larger angular scale for the first splitting, and vice versa. But
> > I'm not sure why you think that's related to the zg plot in figure 3.
> > Are you trying to make a connection to Monika's measurement where we
> > see that large Rg jets have a more steeply falling zg?
>
> Yes, along the same line. The physics should be the same.
> In my perspective, all these results are connected and we are just
> trying to interpret in different ways.
>
> Cheers
> Nihar
>
>
> On 2023-03-10 22:02, Youqi Song wrote:
> > Hi Nihar,
> >
> > We aren't planning to include this projection on slide 35 in figure 2,
> > since the information is contained in the left hand side 2D plot. I
> > would agree that from slide 35, we see that dM=0 jets have on average
> > a larger angular scale for the first splitting, and vice versa. But
> > I'm not sure why you think that's related to the zg plot in figure 3.
> > Are you trying to make a connection to Monika's measurement where we
> > see that large Rg jets have a more steeply falling zg?
> >
> > Best,
> > Youqi
> >
> > On Fri, Mar 10, 2023 at 11:09 AM Nihar Sahoo
> > <nihar AT rcf.rhic.bnl.gov> wrote:
> >
> > > Hi Youqi,
> > >
> > > Thank you for preparing this plot in slide 35.
> > > Do you want to include this figure as one panel of Fig2?
> > >
> > > Now if I compare Zg of fig -3 and Rg plot on slide 35, it looks like
> > > no
> > > grooming (dM=0) case jets have wider angle and vice versa. Is that
> > > correct?
> > >
> > > I will send email request to Rongrong by tomorrow, I am traveling.
> > >
> > > Cheers
> > > Nihar
> > >
> > > On 2023-03-10 17:35, Youqi Song wrote:
> > > > Hi Nihar,
> > > >
> > > > In case my other email got lost in the thread for this week's PWG
> > > > meeting, I would like to point you to slide 35 of
> > https://drupal.star.bnl.gov/STAR/system/files/prelim_request_030923.pdf.
> > > > This might answer your question regarding:
> > > >
> > > > > Do you have a plot to show for different "Delta_M/M" what is the
> > > > > distribution of "Rg"?
> > > > > You could add another panel plot with Fig.3 to show Rg
> > > distribution
> > > > > (Similar to Zg distribution).
> > > > >
> > > > > It is important to show for different "Delta_M/M" regions later
> > > > > splitting dominates by showing Rg distribution in this
> > > measurement.
> > > > Please let us know when you put in the request for PWGC review to
> > > > Rongrong. Thank you!
> > > >
> > > > Best,
> > > > Youqi
> > > >
> > > > On Mon, Mar 6, 2023 at 2:34 PM Youqi Song <youqi.song AT yale.edu>
> > > > wrote:
> > > >
> > > > > Hi Nihar,
> > > > >
> > > > > Thanks for the comments. I have updated my slides here:
> > https://drupal.star.bnl.gov/STAR/system/files/star_collab_meeting_030623.pdf.
> > > > > In addition to Raghav's comments, please find my response below:
> > > > >
> > > > > Best,
> > > > > Youqi
> > > > >
> > > > > > Slide 4:
> > > > >
> > > > > > Where is "PYTHIA6 STAR" on left side "Delta M" plot? And same
> > > for
> > > > > > Fig.2 right.
> > > > >
> > > > > We think that a comparison with the PYTHIA8 Detroit tune should
> > > be
> > > > > sufficient and better since it is a tune that includes newer RHIC
> > > > > data.
> > > > >
> > > > > > What is "Delta_M" distribution for q vs g jet for this collinear
> > > > > > drop jet measurement? Can we say something here on this? It
> > > would
> > > > > > be an important information.
> > > > >
> > > > > > Can we add some PYTHIA simulation for the q vs g jet for these
> > > > > > plots?
> > > > >
> > > > > Please see slide 5 in the updated slides for these.
> > > > >
> > > > > > Slide07
> > > > > > "       "Observed an anti-correlation between the amount of
> > > > > > early-stage
> > > > > > radiation and the angular scale of a later-stage splitting,
> > > where
> > > > > > a
> > > > > > large groomed jet radius indicates small or no branching prior
> > > to
> > > > > > the
> > > > > > SoftDrop splitting "
> > > > > > This statement is not clear what exactly it says.
> > > > > >
> > > > > > I think this conclusion is coming from the statement (Slide-5)
> > > of
> > > > > > "the
> > > > > > dM/M distributions anti-correlated with Rg"
> > > > > > Then it is not clear how do we know these are "early-stage
> > > > > > radiation"
> > > > > > and "later-stage splitting".
> > > > > > More explanation or better paraphrase is needed to make it
> > > clear.
> > > > > Raghav answered this in his response to slide 6 question 3: "the
> > > > > early splits are defined via the definition of the formation time
> > > in
> > > > > QCD which is inversely prop to angle and energy - taken from the
> > > > > splitting functions." I think the cartoon on slide 16 (of the new
> > > > > version) also helps illustrate this point.
> > > > >
> > > > > > "Agreement/disagreement with MC event generators (pending
> > > > > > finalizing
> > > > > > systematic uncertainties)" -> Figures 1,2, and 3 show that MC
> > > > > > event
> > > > > > generators are in agreement with the data. Is not that?
> > > > > > Then why "/disagreement"?
> > > > >
> > > > > We think it's possible that after finalizing the systematics, the
> > > > > error bars in the figures would become smaller and not cover some
> > > of
> > > > > the MC curves. In any case, the main physics message of this
> > > > > measurement (correlations between dM vs zg and Rg) is drawn from
> > > the
> > > > > data themselves, and wouldn't be affected by the comparison with
> > > the
> > > > > MC.
> > > > >
> > > > > > Slide-11
> > > > > >
> > > > > > Are we going to include Jet M distribution as one of
> > > supplementary
> > > > > > figures?
> > > > > > If yes, then it is not clear why do we need this figure as
> > > > > > supplement
> > > > > > material? Particularly "M vs Q".
> > > > > > It sounds like a bit arbitrary.
> > > > > > Could you explain here?
> > > > >
> > > > > We don't plan to include the jet M distributions in supplementary
> > > > > material. As for whether to include "M vs Q", I will leave that
> > > > > decision to Helen and Raghav.
> > > > >
> > > > > > Slide-18,19:
> > > > > >
> > > > > > It shows "hadronization" has biggest effect on the collinear
> > > drop.
> > > > > > Then how reliable is it to say about early and later splitting
> > > as
> > > > > > we
> > > > > > mention in Slide 6-7?
> > > > >
> > > > > Like we have mentioned on slide 19 (slide 20 of the new version),
> > > > > "hadronization smears/shifts the distributions, but the
> > > correlation
> > > > > with and without hadronization is the same." For example, in the
> > > top
> > > > > left figure of slide 20, when we turn off hadronization, in the
> > > > > dashed curves, dM/M decreases with increasing Rg (as we move from
> > > > > blue to green to orange). This is the same trend as the solid
> > > curves
> > > > > with hadronization on. Similarly, for the top right figure, the
> > > > > flattening of zg with increasing dM/M is the same trend between
> > > the
> > > > > dashed and solid curves.
> > > > >
> > > > > On Mon, Mar 6, 2023 at 1:17 PM Raghav Kunnawalkam Elayavalli
> > > via
> > > > > Star-hp-l <star-hp-l AT lists.bnl.gov> wrote:
> > > > >
> > > > > Hi Nihar,
> > > > >
> > > > > Please find a few quick answers from the airport to your
> > > questions
> > > > > below. I will respond to the rest later today after i land and
> > > get
> > > > > to my destination.
> > > > >
> > > > > Cheers
> > > > > Raghav
> > > > >
> > > > > **************************************
> > > > > First Name - Raghav
> > > > > Last Name - Kunnawalkam Elayavalli
> > > > > email - raghav.ke AT vanderbilt.edu
> > > > > website - https://www.raghavke.me [1]  [1]
> > > > >
> > > > > RHIC/AGS UEC member
> > > > > Assistant Professor of Physics
> > > > > Stevenson Center 6410
> > > > > Physics & Astronomy Department
> > > > > Vanderbilt University
> > > > > Nashville, TN 37235-1807
> > > > > <they/them>
> > > > > **************************************
> > > > >
> > > > > On Mar 2, 2023, at 7:07 AM, Nihar Sahoo via Star-hp-l
> > > > > <star-hp-l AT lists.bnl.gov> wrote:
> > > > >
> > > > > Hello Youqi,
> > > > >
> > > > > As I mentioned we will discuss with Rongrong to find a nearest
> > > date
> > > > > for PWGC review.
> > > > >
> > > > > In the mean time, Please find my comments below on these nice
> > > > > results.
> > > > >
> > > > > SLide-4:
> > > > >
> > > > > What is the extra information we get from the right side plot of
> > > > > obeservable "a"? Is not that the left plot "Delta M" is
> > > sufficient
> > > > > to measure Collinear drop observables?
> > > > > The quick answer for us is that - theorists are able to calculate
> > > > > ‘a’ as opposed to ‘\delta M’ because a is normalized by
> > > the
> > > > > jet pT. this makes the calculation in SCET doable and easier on
> > > the
> > > > > theoretical uncertainties as they don’t need to vary the energy
> > > > > scale.
> > > > >
> > > > > Where is "PYTHIA6 STAR" on left side "Delta M" plot? And same for
> > > > > Fig.2 right.
> > > > > We can certainly add it to the plots as we have done in the past.
> > > > > Given that we have the pythia 8 detroit tune here, it more or
> > > less
> > > > > covers the variation.
> > > > >
> > > > > What is "Delta_M" distribution for q vs g jet for this collinear
> > > > > drop jet measurement?
> > > > > Can we say something here on this? It would be an important
> > > > > information.
> > > > > from a purely conceptual basis - we know that the jet mass
> > > > > distinguishes q vs g jets, we also know that groomed mass
> > > > > distinguishes q vs g less but we can assume that the
> > > discriminative
> > > > > power is probably less. Therefore, delta-m, i would naively
> > > assume
> > > > > has a much weaker ability to distinguish between q vs g jets. In
> > > our
> > > > > sample of jets, the q vs g fraction steadily increases from about
> > > > > 60-40 for the 20ish GeV jets. so increasing the jet pT does
> > > change
> > > > > Can we add some PYTHIA simulation for the q vs g jet for these
> > > > > plots?
> > > > > I think we had truth level quark and gluon jet curves for the m
> > > vs
> > > > > charge back during the preliminary discussion. Based on the
> > > > > discussion i mentioned above, we can produce this curve but i
> > > hope
> > > > > it doesnt hold up the forward progress on the paper.
> > > > >
> > > > > Slide-6:
> > > > >
> > > > > 1. Do you have a plot to show for different "Delta_M/M" what is
> > > the
> > > > > distribution of "Rg"?
> > > > > You could add another panel plot with Fig.3 to show Rg
> > > distribution
> > > > > (Similar to Zg distribution).
> > > > >
> > > > > It is important to show for different "Delta_M/M" regions later
> > > > > splitting dominates by showing Rg distribution in this
> > > measurement.
> > > > > So you want to see the other axis projection on figure 2 then? it
> > > is
> > > > > possible sure but isnt the information already available in the
> > > dM/M
> > > > > vs Rg?
> > > > >
> > > > > 2. "Similar trend for higher pT range" ->Where do you get this
> > > > > conclusion? There is only one pT range 20-30 GeV/c is shown.
> > > (Same
> > > > > for Slide-5)
> > > > > we have analyzed the other pT bins and maybe we can show it in
> > > the
> > > > > appendix.
> > > > >
> > > > > 3. "Suggests how the amount of initial wide and soft emission
> > > …"
> > > > > ->How do we know these are "wide angle" emission?
> > > > > this is also an answer for the question below - the early splits
> > > are
> > > > > defined via the definition of the formation time in QCD which is
> > > > > inversely prop to angle and energy - taken from the splitting
> > > > > functions.
> > > > >
> > > > > Slide07
> > > > > " "Observed an anti-correlation between the amount of early-stage
> > > > > radiation and the angular scale of a later-stage splitting, where
> > > a
> > > > > large groomed jet radius indicates small or no branching prior to
> > > > > the SoftDrop splitting "
> > > > > This statement is not clear what exactly it says.
> > > > >
> > > > > I think this conclusion is coming from the statement (Slide-5) of
> > > > > "the dM/M distributions anti-correlated with Rg"
> > > > > Then it is not clear how do we know these are "early-stage
> > > > > radiation" and "later-stage splitting".
> > > > > More explanation or better paraphrase is needed to make it clear.
> > > > >
> > > > > "Agreement/disagreement with MC event generators (pending
> > > finalizing
> > > > > systematic uncertainties)" -> Figures 1,2, and 3 show that MC
> > > event
> > > > > generators are in agreement with the data. Is not that?
> > > > > Then why "/disagreement"?
> > > > >
> > > > > Slide-11
> > > > >
> > > > > Are we going to include Jet M distribution as one of
> > > supplementary
> > > > > figures?
> > > > > If yes, then it is not clear why do we need this figure as
> > > > > supplement material? Particularly "M vs Q".
> > > > > It sounds like a bit arbitrary.
> > > > > Could you explain here?
> > > > >
> > > > > Slide-18,19:
> > > > >
> > > > > It shows "hadronization" has biggest effect on the collinear
> > > drop.
> > > > > Then how reliable is it to say about early and later splitting as
> > > we
> > > > > mention in Slide 6-7?
> > > > >
> > > > > Thank you
> > > > > Nihar
> > > > >
> > > > > On 2023-03-02 03:19, Nihar Sahoo via Star-hp-l wrote:
> > > > > Hello Youqi,
> > > > > Thank you for this paper proposal.
> > > > > Yes, results and the physics conclusions look good to me.
> > > > > We can move forward for the PWGC review and we will discuss with
> > > > > Rongrong to find a date.
> > > > > Cheers
> > > > > Nihar
> > > > > On 2023-03-01 21:40, Youqi Song via Star-hp-l wrote:
> > > > > Hi conveners,
> > > > > Here are the slides for the presentation yesterday where we
> > > updated
> > > > > the paper proposal
> > https://drupal.star.bnl.gov/STAR/system/files/star_collab_meeting_022823_1.pdf.
> > > > > We think we are ready to move to PWGC review and Barbara is also
> > > > > happy
> > > > > with us moving forward. Please let us know if you have any
> > > questions
> > > > > or comments. Thank you!
> > > > > Best,
> > > > > Youqi, Raghav and Helen
> > > > > On Thu, Feb 16, 2023 at 1:18 PM Youqi Song
> > > <youqi.song AT yale.edu>
> > > > > wrote:
> > > > > Hi HP conveners,
> > > > > I would like to follow up on the paper proposal I presented at
> > > our
> > > > > PWG meeting last week. I have updated my slides here
> > https://drupal.star.bnl.gov/STAR/system/files/paper_proposal_021023.pdf
> > > > > based on the feedback I got from the meeting:
> > > > > Slide 12 - I've made the conclusions in a bullet point form.
> > > > > Hopefully this highlights our physics messages more crisply.
> > > > > Slide 17 - I included an example of a large dM jet from a PYTHIA
> > > > > event.
> > > > > As mentioned last week, we have been talking to some theorists
> > > who
> > > > > agreed to provide some predictions for the collinear jet mass. I
> > > am
> > > > > also finalizing the systematic uncertainties so that we can
> > > arrive
> > > > > at a more concrete comparison with the MC generators.
> > > > > We would like to know if this analysis could be pushed to PWGC
> > > > > review soon or if there is anything else that people would like
> > > us
> > > > > to prepare for. Please let us know if you have any questions or
> > > > > comments. Thanks!
> > > > > Best,
> > > > > Youqi
> > > > > _______________________________________________
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> > > > Links:
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> > > > [1]
> > https://urldefense.com/v3/__https://www.raghavke.me__;!!P4SdNyxKAPE!FlvPnXOKF9djgg4Y2Q21p12n8HFvVB_ADtELu-y7DrWGHVMqt12ZRew1QIWVBEUA3A551BZZAZ83j2OLynIulsXRMHlYRstbbQ$
> >
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