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We report a high precision measurement of the transverse single spin asymmetry $A_N$ at the center of mass energy $\sqrt{s}=200$ GeV in elastic proton-proton scattering by the STAR experiment at RHIC. The $A_N$ was measured in the four-momentum transfer squared $t$ range $0.003 \leqslant |t| \leqslant 0.035$ $\GeVcSq$, the region of a significant interference between the electromagnetic and hadronic scattering amplitudes. The measured values of $A_N$ and its $t$-dependence are consistent with a vanishing hadronic spin-flip amplitude, thus providing strong constraints on the ratio of the single spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated by the Pomeron amplitude at this $\sqrt{s}$, we conclude that this measurement addresses the question about the presence of a hadronic spin flip due to the Pomeron exchange in polarized proton-proton elastic scattering.

3 data tables match query

Table 3

The asymmetry $\varepsilon(\varphi)/(P_B + P_Y)$ for various $t$-intervals.

Table 4

The measured single spin asymmetry $A_N$ for five $-t$ intervals.

Table 5

Fitted value of $r_5$.

Particle dependence of azimuthal anisotropy and nuclear modification of particle production at moderate p(T) in Au + Au collisions at s(NN)**(1/2) = 200-GeV.

The STAR collaboration Adams, John ; Adler, C. ; Aggarwal, M.M. ; et al.

Phys.Rev.Lett. 92 (2004) 052302, 2004.

Inspire Record 620309 DOI 10.17182/hepdata.93260

We present STAR measurements of the azimuthal anisotropy parameter $v_2$ and the binary-collision scaled centrality ratio $R_{CP}$ for kaons and lambdas ($\Lambda+\bar{\Lambda}$) at mid-rapidity in Au+Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV. In combination, the $v_2$ and $R_{CP}$ particle-type dependencies contradict expectations from partonic energy loss followed by standard fragmentation in vacuum. We establish $p_T \approx 5$ GeV/c as the value where the centrality dependent baryon enhancement ends. The $K_S^0$ and $\Lambda+\bar{\Lambda}$ $v_2$ values are consistent with expectations of constituent-quark-number scaling from models of hadron fromation by parton coalescence or recombination.

9 data tables match query

Table 1.1

The minimum bias (0-80% of the collision cross-section) v2(pT) of K0s. Errors listed include statistical and point-to-point systematic uncertainties from the background. Additional non-flow systematic uncertainties are approximately -20%.

Table 1.2

The minimum bias (0-80% of the collision cross-section) v2(pT) of Lambda+Lambdabar. Errors listed include statistical and point-to-point systematic uncertainties from the background. Additional non-flow systematic uncertainties are approximately -20%.

Table 1.3

The minimum bias (0-80% of the collision cross-section) v2(pT) of charged hadrons. Errors listed include statistical and point-to-point systematic uncertainties from the background. Additional non-flow systematic uncertainties are approximately -20%.

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Measuring K$^0_{\rm S}$K$^{\rm{\pm}}$ interactions using pp collisions at $\sqrt{s}=7$ TeV

The ALICE collaboration Acharya, Shreyasi ; Torales - Acosta, Fernando ; Adamova, Dagmar ; et al.

Phys.Lett.B 790 (2019) 22-34, 2019.

Inspire Record 1695028 DOI 10.17182/hepdata.88298

We present the first measurements of femtoscopic correlations between the K$^0_{\rm S}$ and K$^{\rm \pm}$ particles in pp collisions at $\sqrt{s}=7$ TeV measured by the ALICE experiment. The observed femtoscopic correlations are consistent with final-state interactions proceeding solely via the $a_0(980)$ resonance. The extracted kaon source radius and correlation strength parameters for K$^0_{\rm S}$K$^{\rm -}$ are found to be equal within the experimental uncertainties to those for K$^0_{\rm S}$K$^{\rm +}$. Results of the present study are compared with those from identical-kaon femtoscopic studies also performed with pp collisions at $\sqrt{s}=7$ TeV by ALICE and with a K$^0_{\rm S}$K$^{\rm \pm}$ measurement in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV. Combined with the Pb-Pb results, our pp analysis is found to be compatible with the interpretation of the $a_0(980)$ having a tetraquark structure instead of that of a diquark.

19 data tables match query

Figure 1a

Raw K0s K+ correlation function for all kT

Figure 1b

Raw K0s K+ correlation function for kT < 0.85 GeV/c

Figure 1c

Raw K0s K+ correlation function for kT > 0.85 GeV/c

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Two Particle Correlations and Regions of Proton Emittance Regions in $p$ Ta Interactions at $p=10$-{GeV}/$c$

THE STUDY OF p C INTERACTIONS AT p (p) = 10-GeV/c WITH THE EMISSION OF CUMULATIVE DEUTERONS

Nuclear Matter Excitation in Pion - Xenon Collisions at 3.5-GeV/c: Inclusive Spectra of Neutral Pions

Characteristics of neutral pion production process in pi- Xe nuclear collisions at 3.5-GeV/c momentum

Proton Multiplicity Distributions in Pion - Xenon Nucleus Collisions at 3.5-{GeV}/c

Energy Dependence of the Effective Cross-Section of the e+ e- Pair Production by gamma Quanta in Liquid Xenon

TWO PROTON CORRELATIONS IN alpha C INTERACTIONS AT 4.2-GeV/c PER NUCLEON

Single Spin Asymmetry $A_N$ in Polarized Proton-Proton Elastic Scattering at $\sqrt{s}=200$ GeV

Particle dependence of azimuthal anisotropy and nuclear modification of particle production at moderate p(T) in Au + Au collisions at s(NN)**(1/2) = 200-GeV.

Measuring K$^0_{\rm S}$K$^{\rm{\pm}}$ interactions using pp collisions at $\sqrt{s}=7$ TeV