Nuclear modification factor as a function of $ p_{\mathrm{T}} $ in different $y^*$ intervals for prompt $ D ^0 $ mesons in the (top) forward and (bottom) backward regions. The error bars show the statistical uncertainties and the boxes show the systematic uncertainties. The LHCb results at $\sqrt{s_{\scriptscriptstyle\text{NN}}} = 5.02\text{ Te V} $ \cite{LHCb-PAPER-2017-015} and theoretical calculations at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =8.16\text{ Te V} $ from Refs. \cite{Eskola:2016oht,Kovarik:2015cma,Ducloue:2016ywt,Ma:2018bax,Arleo:2021bpv} are also shown. For LHCb results at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =5.02\text{ Te V} $, the error bars show the quadric sum of statistical and systematic uncertainties.

Nuclear modification factor as a function of $x_\mathrm{exp}$ in different $Q^2_\mathrm{exp}$ intervals for prompt $ D ^0 $ mesons for LHCb results at $\sqrt{s_{\scriptscriptstyle\text{NN}}} = 8.16\text{ Te V} $ and $\sqrt{s_{\scriptscriptstyle\text{NN}}} =5.02$ \cite{LHCb-PAPER-2017-015} and the ALICE result at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =5.02\text{ Te V} $ \cite{ALICE:2019fhe}. Theoretical calculations at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =8.16\text{ Te V} $ from Refs. \cite{Eskola:2016oht,Kovarik:2015cma} are also shown. The horizontal error bars account for the maximum and minimum $x_\mathrm{exp}$ values for a given $( p_{\mathrm{T}} , y^*)$ interval and the vertical error bars show the quadric sum of statistical and systematic uncertainties.

Distributions and fit results of (left) $M( K \pi )$ and (right) $\log_{10}\left(\chi^2_{\text{IP}}\right)$ \ for inclusive $ D ^0$ mesons in the forward data sample in the kinematic range of $2.5< p_{\mathrm{T}} <3.0\text{ Ge V /}c $ and $3.25<y^*<3.50$. For the $\log_{10}\left(\chi^2_{\text{IP}}\right)$ fit, the data are weighted using the sPlot method to subtract the background component.

Distributions and fit results of (left) $M( K \pi )$ and (right) $\log_{10}\left(\chi^2_{\text{IP}}\right)$ \ for inclusive $ D ^0$ mesons in the backward data sample in the kinematic range of $2.5< p_{\mathrm{T}} <3.0\text{ Ge V /}c $ and $-4.50<y^*<-4.25$. For the $\log_{10}\left(\chi^2_{\text{IP}}\right)$ fit, the data are weighted using the sPlot method to subtract the background component.

Double-differential cross-sections of prompt $ D ^0$ mesons in $p$Pb collisions in the (top) forward and (bottom) backward rapidity regions. To display the differential cross-section values in different rapidity intervals, multiplicative factors of $10^{-n}$ are used with $n$ increasing with rapidity value. The uncertainties are smaller than the symbol size.

Nuclear modification factor as a function of $ p_{\mathrm{T}} $ in different $y^*$ intervals for prompt $ D ^0 $ mesons in the forward regions for $2.0<y^*<4.0$. The error bars show the statistical uncertainties and the boxes show the systematic uncertainties. The theoretical calculations from Refs. \cite{Eskola:2016oht,Kovarik:2015cma,Ma:2018bax,Arleo:2021bpv} are also shown.

Nuclear modification factor as a function of $ p_{\mathrm{T}} $ in different $y^*$ intervals for prompt $ D ^0 $ mesons in the backward regions for $-4.5<y^*<-2.5$. The error bars show the statistical uncertainties and the boxes show the systematic uncertainties. The theoretical calculations from Refs. \cite{Eskola:2016oht,Kovarik:2015cma,Arleo:2021bpv} are also shown.

Nuclear modification factor for prompt $ D ^0 $ mesons as a function of $y^*$ in (left) the full- $ p_{\mathrm{T}}$ range and (right) the high- $ p_{\mathrm{T}}$ range. The error bars show the statistical uncertainties and the boxes show the systematic uncertainties. The LHCb results at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =5.02\text{ Te V} $ \cite{LHCb-PAPER-2017-015} and theoretical calculations at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =8.16\text{ Te V} $ from Refs. \cite{Eskola:2016oht,Kovarik:2015cma,Ducloue:2016ywt,Ma:2018bax} are also shown. For the LHCb results at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =5.02\text{ Te V} $, the error bars show the quadratic sum of statistical and systematic uncertainties. On the left, the $ p_{\mathrm{T}}$ range is $0 < p_{\mathrm{T}} < 15\text{ Ge V /}c $ for the calculations with nPDFs of EPPS16 and nCTEQ15.

Forward-backward production ratio for prompt $ D ^0$ mesons as a function of $ p_{\mathrm{T}}$ , integrated over the common rapidity range $2.5 < |y^*| < 4.0$. The error bars show the statistical uncertainties and the boxes show the systematic uncertainties. The LHCb results at $\sqrt{s_{\scriptscriptstyle\text{NN}}} = 5.02\text{ Te V} $ \cite{LHCb-PAPER-2017-015} and theoretical calculations at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =8.16\text{ Te V} $ from Refs. \cite{Eskola:2016oht,Kovarik:2015cma,Arleo:2021bpv} are also shown. For the LHCb results at $\sqrt{s_{\scriptscriptstyle\text{NN}}} =5.02\text{ Te V} $, the error bars show the quadratic sum of statistical and systematic uncertainties.

Forward and backward production ratio $R_{\mathrm{FB}}$ for prompt $ D ^0$ mesons as a function of $ p_{\mathrm{T}}$ in different $|y^*|$ intervals. The error bars show the statistical uncertainties and the boxes show the systematic uncertainties. The theoretical calculations from Refs. \cite{Eskola:2016oht,Kovarik:2015cma} are also shown.

Animated gif made out of all figures.

Systematic uncertainties considered in this measurement, in %. The range indicates the minimum and the maximum value among the two-dimensional $ p_{\mathrm{T}}$ and $y^*$ intervals. The systematic uncertainties due to simulation sample size, mass fit and $\log_{10}\left(\chi^2_{\text{IP}}\right)$ fit are uncorrelated across the intervals. The other sources of systematic uncertainties are fully correlated between different intervals.

Double-differential cross-sections for prompt $ D ^0$ mesons in intervals of $ p_{\mathrm{T}}$ and $y^*$ in forward rapidity regions. The first uncertainty is statistical, the second is the component of the systematic uncertainty that is uncorrelated across intervals and the third is the correlated component.

Double-differential cross-sections for prompt $ D ^0$ mesons in intervals of $ p_{\mathrm{T}}$ and $y^*$ in backward rapidity regions. The first uncertainty is statistical, the second is the component of the systematic uncertainty that is uncorrelated across intervals and the third is the correlated component.

Nuclear modification factor $R_{p\mathrm{Pb}}$ for prompt $ D ^0$ mesons in intervals of $ p_{\mathrm{T}}$ and $y^*$ for $ p_{\mathrm{T}} <10\text{ Ge V /}c $. The first uncertainty is statistical and the second is the systematic.

Nuclear modification factor $R_{p\mathrm{Pb}}$ for prompt $ D ^0$ mesons in intervals of $ p_{\mathrm{T}}$ and $y^*$ for $ p_{\mathrm{T}} <10\text{ Ge V /}c $. The first uncertainty is statistical and the second is systematic.

Forward-backward production ratio $R_\mathrm{FB}$ for prompt $ D ^0$ mesons as a function of $ p_{\mathrm{T}}$ , integrated over $2.5<|y^*|<4.0$. The first uncertainty is statistical, the second is the component of the systematic uncertainty that is uncorrelated across intervals and the third is the correlated component.

Supplementary material full pdf

This ZIP file contains the supplementary for publication LHCb-PAPER-2022-007 The files are: supplementary.pdf: the double-differential cross-sections of D0 production for forward and backward data plotted in another format Fig10.*: figures for the double-differential cross-sections in forward rapidity regions Fig11.*: figures for the double-differential cross-sections in background rapidity regions