Multiplicity and rapidity dependence of ${\rm K}^*(892)^0$ and $φ(1020)$ production in p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV

The transverse-momentum ($p_{\rm T}$) spectra of ${\rm K}^*(892)^0$ and $\phi(1020)$ measured with the ALICE detector up to $p_{\rm T}$ = 16 GeV/$c$ in the rapidity range $-1.2 <~ y <~ 0.3$, in p-Pb collisions at center-of-mass energy per nucleon-nucleon collision $\sqrt{s_{\rm NN}}$ = 5.02 TeV are presented as a function of charged particle multiplicity and rapidity. The measured $p_{\rm T}$ distributions show a dependence on both multiplicity and rapidity at low $p_{\rm T}$ whereas no significant dependence is observed at high $p_{\rm T}$. A rapidity dependence is observed in the $p_{\rm T}$-integrated yield (d$N$/d$y$), whereas the mean transverse momentum ($\left<~ p_{\rm T} \right>$) shows a flat behavior as a function of rapidity. The rapidity asymmetry ($Y_{\rm asym}$) at low $p_{\rm T}$ ( <~ 5 GeV/$c$) is more significant for higher multiplicity classes. At high $p_{\rm T}$, no significant rapidity asymmetry is observed in none of the multiplicity classes. Both ${\rm K}^*(892)^0$ and $\phi(1020)$ show similar $Y_{\rm asym}$. The nuclear modification factor ($Q_{\rm CP}$) as a function of $p_{\rm T}$ shows a Cronin-like enhancement at intermediate $p_{\rm T}$, which is more prominent at higher rapidities (Pb-going direction) and in higher multiplicity classes. At high $p_{\rm T}$ (> 5 GeV/$c$), the $Q_{\rm CP}$ values are greater than unity and no significant rapidity dependence is observed.

 

Submitted to: EPJC
e-Print: arXiv:2204.10263 | PDF | inSPIRE
Figure group

Figure 1

Invariant mass distributions after combinatorial background subtraction for \kstar and \phim candidates in the multiplicity class 0--10$\%$ and transverse momentum range 2.2 $\leq$ $p_{\mathrm{T}}$ $

Figure 2

Top panels: The transverse momentum spectra of \kstar (left) and \phim (right) mesons for five rapidity intervals within $-$1.2 $

Figure 3

The \pt integrated yield (d$N/\mathrm{d}y$) (top panels) and mean transverse momentum ($\langle p_{\mathrm{T}} \rangle$) (bottom panels) for \kstar (left) and \phim (right) mesons as a function of $y$ measured for the multiplicity class 0-100$\%$ in \pPb collisions at \snn $=$ 5.02 TeV. The predictions from EPOS-LHC~, EPOS3 with and without UrQMD~, DPMJET~, HIJING~ and PYTHIA8/Angantyr~ are shown as different curves. The statistical uncertainties are represented as bars whereas the boxes indicate total systematic uncertainties.

Figure 4

The \pt integrated yield (d$N/\mathrm{d}y$) (upper panels) and mean transverse momentum ($\langle p_{\mathrm{T}} \rangle$) (bottom panels) for \kstar (left) and \phim (right) mesons as a function of $y$, divided by the d$N/\mathrm{d}y$ and $\langle p_{\mathrm{T}} \rangle$ at $y = 0$ for the multiplicity class 0--100$\%$ in \pPb collisions at \snn $=$ 5.02 TeV The predictions from EPOS-LHC~, EPOS3 with and without UrQMD~, DPMJET~, HIJING~ and PYTHIA8/Angantyr~ are shown as different curves The statistical uncertainties are represented as bars whereas the boxes indicate total systematic uncertainties.

Figure 5

Rapidity asymmetry (Yasym) of K∗0 (red circles) and φ (blue squares) meson production as a function of pT in the rapidity range 0 < |y| < 0.3 for various multiplicity classes in p–Pb collisions at √sNN = 5.02 TeV. The statistical uncertainties are shown as bars whereas the boxes represent the systematic uncertainties on the measurements.

Figure 6

The comparison of experimental results of Yasym for K∗0 and φ meson production as a function of pT in the rapidity range 0 < |y| < 0.3 with the model predictions from EPOS-LHC [33], EPOS3 with and without UrQMD [36, 37], DPMJET [38], HIJING [39] and PYTHIA8/Angantyr [40]. Data points are shown with blue markers, and model predictions are shown by different color bands, where bands represent the statistical uncertainity of the model. The statistical uncertainties on the data points are represented as bars whereas the boxes indicate total systematic uncertainties.

Figure 7

The QCP of K∗0 (red circles) and φ (blue squares) mesons as a function of pT for 0–10% / 40–100% (top panels) and 10–40% / 40–100% (bottom panels) in various rapidity intervals within the range −1.2 < y < 0.3 in p–Pb collisions at √sNN = 5.02 TeV. The statistical and systematic uncertainties are represented by vertical bars and boxes, respectivel

Figure 8

The $Q_\mathrm{CP}$ of \kstar (red circles) and \phim(blue squares) mesons as a function of rapidity for \mbox{0--10 $\%$ / 40--100 $\%$} (solid markers) and 10--40$\%$ / 40--100$\%$ (open markers) in \pPb collisions at \mbox{\snn $=$ 5.02 TeV}. The solid and doted lines represents the linear fit to data. The statistical and systematic uncertainties are represented by vertical bars and boxes on the measurements, respectively.

Figure 9

The \pt integrated yield (d$N/\mathrm{d}y$) (top panels) and mean transverse momentum ($\langle p_{\mathrm{T}} \rangle$) (bottom panels) for \kstar (left panels) and \phim (right panels) mesons as a function of $y$ measured for the multiplicity classes 0--10$\%$, 10--40$\%$ and 40--100$\%$ in \pPb collisions at \snn $=$ 5.02 TeV. The statistical uncertainties are represented as bars whereas boxes indicate the total systematic uncertainties on the measurements.