STAR Flow, Chirality and Vorticity PWG

[subhash <subhash AT rcf.rhic.bnl.gov>]

Dear Qiang,

I sign off with a few additional suggestions.

Please check the formatting of abstract. I think having two paragraph is 
okay.

l#14: Similarly, the local polarization of Λ and Λbar hyperons are 
predicted to be different due to the polarization induced by the 
gradient of baryonic chemical potential (analogous to the electric 
field) and called baryonic spin Hall effect.

l#21: Please unify Λ or, $\Lambda$

l#22: for the later analysis. Remove "covering a wide range of 
energies."

Thanks and regards,
Subhash

On 2023-04-22 09:09 AM, Prithwish Tribedy via Star-fcv-l wrote:
> Dear Qiang,
>
> Nice abstract! Please consider the following comments on version 2.
>
> General comments: Your original abstract is a bit longer. I have
> proposed to shorten it a bit by like 20 words. The reference you have
> added are ok but not the best suited for the context. The
> McLerran-Skokov paper is about B-field with conductivity, but I am not
> sure it talks about Lambda polarization, you can keep it and I don't
> have a more appropriate suggestion at this moment. The PRL paper by Fu
> et al talks about shear-induced vorticity, again the context is not
> clear.
>
> Here are my text suggestion:
>
> "A significant non-zero global spin polarization of $\Lambda$ hyperons
> by STAR collaboration in the 1st phase of RHIC Beam Energy Scan (BES)
> provided the evidence of enormous vorticity in Quark Gluon Plasma
> (QGP) medium induced by the large angular momentum interactions. In
> these studies, there is a hint of larger $\bar{\Lambda}$ global
> polarization relative to $\Lambda$, consistent with expectation from a
> strong late-stage magnetic field sustained by the QGP. Such a
> splitting could reveal information about the electric conductivity of
> the QGP, and is therefore of great interest [1]."
>
> -->
>
> "STAR's measurement of a significant global spin polarization of
> $\Lambda$ hyperons in the first phase of RHIC BES provides evidence of
> vorticity in the QGP. The data also hinted at a larger polarization of
> $\bar{\Lambda}$, which is expected from a strong late-stage magnetic
> field sustained by the medium. A decisive experimental test of this
> splitting would be highly significant, as it could reveal valuable
> information about the electric conductivity of the QGP [1]."
>
>
> "Recent theoretical calculations also indicate that the gradient of
> baryonic chemical potential (analogous to the electric field) can
> induce a sizable spin Hall current in Au+Au collisions at
> $\sqrt{s_{\mathrm{NN}}}$ $\sim$ 10 GeV. The predicted pattern and
> energy dependence of the difference between local polarization of
> $\Lambda$ and $\bar{\Lambda}$ hyperons ($P_x^\mathrm{net} \sin(2\Psi_2
> - \phi_p^\ast), P_y^\mathrm{net} \cos(2\Psi_2 - \phi_p^\ast),
> P_z^\mathrm{net} \sin(2\Psi_2 - \phi_p^\ast)$, $P_{x,y,z}^\mathrm{net}
> = P_{x,y,z}^{\Lambda} - P_{x,y,z}^{\bar{\Lambda}}$, where $\Psi_2$ is
> the second-order event-plane angle and $\phi_p^\ast$ is the azimuthal
> angle of the proton in $\Lambda$'s rest frame) at RHIC BES energies
> are significantly different with and without the presence of baryonic
> spin Hall current [2,3]."
>
> -->
>
> "Similarly, the local polarization of $\Lambda$ and $\bar{\Lambda}$
> hyperons are predicted to be different due to the gradient of baryonic
> chemical potential (analogous to the electric field) induced by the
> spin Hall effect. This effect is expected to be observable through the
> energy dependence of the angular modulation of the net polarization,
> $P^\mathrm{net}_{x,y,z} = P^\Lambda_{x,y,z} -
> P^{\bar{\Lambda}}_{x,y,z}$, as measured by
> $P^\mathrm{net}_{x,z}\sin(2\Psi_2-\phi_p^*)$ and
> $P^\mathrm{net}_{y}\cos(2\Psi_2-\phi_p^*)$, where $\Psi_2$ is the
> second-order event-plane angle and $\phi_p^*$ is the azimuthal angle
> of the proton in $\Lambda$'s rest frame [2,3]."
>
>
>
> "During the 2nd phase of BES, STAR has collected high-statistics data
> sets with upgraded detectors, allowing precision measurements of
> polarization difference. In this talk, we will present the splitting
> in global and local spin polarization of Λ hyperons in RHIC BES-II
> Au+Au collisions at √sNN =7.7, 11.5, 14.6, 19.6, and 27 GeV."
>
> -->
>
> We report the first measurement of splitting in global and local spin
> polarization of $\Lambda$ hyperons in heavy ion collisions using data
> collected by the STAR experiment during the second phase of the RHIC
> Beam Energy Scan (BES II) with the upgraded STAR detector. We used
> Au+Au collisions at $\sqrt{s_{\mathrm{NN}}} = 19.6$ and 27 GeV for the
> former, and the same collision system at $\sqrt{s_{\mathrm{NN}}} =
> 7.7--27$ GeV for the latter, covering a wide range of energies.
>
> "The polarization measurements will also be presented differentially
> as a function of centrality, transverse momentum, and rapidity."
>
> -->
>
> "We will also present the polarization measurements as a function of
> centrality, transverse momentum, and rapidity."
>
> "These global and local polarization measurements will help reveal
> information about the late-stage magnetic field sustained by the QGP,
> as well as probe predicted Spin Hall currents in a highly dense
> baryonic environment."
>
> -->
>
> "Our measurements provide important insights on the late-stage
> magnetic field sustained by the QGP, as well as probe predicted spin
> Hall currents in a highly dense baryonic environment."
>
>
> Best,
> Prithwish
>
>
>
> On 2023-04-18 23:20, webmaster--- via Star-fcv-l wrote:
> > Dear star-fcv-l AT lists.bnl.gov members,
> >
> > Qiang Hu (qianghu AT impcas.ac.cn) has submitted a material for a review, 
> > please
> > have a look:
> > https://drupal.star.bnl.gov/STAR/node/63469
> >
> > Deadline: 2023-05-01
> > ---
> > If you have any problems with the review process, please contact
> > webmaster AT www.star.bnl.gov
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