Azimuthal correlations of prompt D mesons with charged particles in pp and p–Pb collisions at $$\varvec{\sqrt{s_\mathrm{NN}}} = 5.02\ \hbox {TeV}$$

Abstract

Abstract The measurement of the azimuthal-correlation function of prompt D mesons with charged particles in pp collisions at $$\sqrt{s} =5.02\ \hbox {TeV}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>5.02</mml:mn> <mml:mspace/> <mml:mtext>TeV</mml:mtext> </mml:mrow> </mml:math> and p–Pb collisions at $$\sqrt{s_{\mathrm{NN}}} = 5.02\ \hbox {TeV}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msqrt> <mml:msub> <mml:mi>s</mml:mi> <mml:mi>NN</mml:mi> </mml:msub> </mml:msqrt> <mml:mo>=</mml:mo> <mml:mn>5.02</mml:mn> <mml:mspace/> <mml:mtext>TeV</mml:mtext> </mml:mrow> </mml:math> with the ALICE detector at the LHC is reported. The $$\mathrm{D}^{0}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow> <mml:mi>D</mml:mi> </mml:mrow> <mml:mn>0</mml:mn> </mml:msup> </mml:math> , $$\mathrm{D}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow> <mml:mi>D</mml:mi> </mml:mrow> <mml:mo>+</mml:mo> </mml:msup> </mml:math> , and $$\mathrm{D}^{*+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow> <mml:mi>D</mml:mi> </mml:mrow> <mml:mrow> <mml:mrow/> <mml:mo>∗</mml:mo> <mml:mo>+</mml:mo> </mml:mrow> </mml:msup> </mml:math> mesons, together with their charge conjugates, were reconstructed at midrapidity in the transverse momentum interval $$3&lt; p_\mathrm{T} &lt; 24\ \hbox {GeV}/c$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>3</mml:mn> <mml:mo>&lt;</mml:mo> <mml:msub> <mml:mi>p</mml:mi> <mml:mi>T</mml:mi> </mml:msub> <mml:mo>&lt;</mml:mo> <mml:mn>24</mml:mn> <mml:mspace/> <mml:mtext>GeV</mml:mtext> <mml:mo>/</mml:mo> <mml:mi>c</mml:mi> </mml:mrow> </mml:math> and correlated with charged particles having $$p_\mathrm{T} &gt; 0.3\ \hbox {GeV}/c$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>p</mml:mi> <mml:mi>T</mml:mi> </mml:msub> <mml:mo>&gt;</mml:mo> <mml:mn>0.3</mml:mn> <mml:mspace/> <mml:mtext>GeV</mml:mtext> <mml:mo>/</mml:mo> <mml:mi>c</mml:mi> </mml:mrow> </mml:math> and pseudorapidity $$|\eta | &lt; 0.8$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>|</mml:mo> <mml:mi>η</mml:mi> <mml:mo>|</mml:mo> <mml:mo>&lt;</mml:mo> <mml:mn>0.8</mml:mn> </mml:mrow> </mml:math> . The properties of the correlation peaks appearing in the near- and away-side regions (for $$\Delta \varphi \approx 0$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>φ</mml:mi> <mml:mo>≈</mml:mo> <mml:mn>0</mml:mn> </mml:mrow> </mml:math> and $$\Delta \varphi \approx \pi $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>Δ</mml:mi> <mml:mi>φ</mml:mi> <mml:mo>≈</mml:mo> <mml:mi>π</mml:mi> </mml:mrow> </mml:math> , respectively) were extracted via a fit to the azimuthal correlation functions. The shape of the correlation functions and the near- and away-side peak features are found to be consistent in pp and p–Pb collisions, showing no modifications due to nuclear effects within uncertainties. The results are compared with predictions from Monte Carlo simulations performed with the PYTHIA, POWHEG+PYTHIA, HERWIG, and EPOS 3 event generators.