cern.ch

Study of prompt D$^0$ meson production in pPb collisions at $\sqrt{s}$=5 TeV

[to restricted-access page]

Abstract

Production of prompt D$^0$ mesons is studied in proton-lead and lead-proton collisions recorded at the LHCb detector at the LHC. The data sample corresponds to an integrated luminosity of $1.58\pm0.02$ nb$^{-1}$ recorded at a nucleon-nucleon centre-of-mass energy of $\sqrt{s}=5$ TeV. Measurements of the differential cross-section, the forward-backward production ratio and the nuclear modification factor are reported using D$^0$ candidates with transverse momenta less than 10 GeV/c and rapidities in the ranges $1.5<y^*<4.0$ and $-5.0<y^*<-2.5$ in the nucleon-nucleon centre-of-mass system.

Figures and captions

The (left) $M(K^\mp\pi^\pm)$ and (right) $\log_{10}(\chi^2_{\text{\rm IP}} ( D ^0 )) $ distributions and the fit result for the inclusive $ D ^0 $ mesons in the forward data sample in the kinematic range of $2< p_{\mathrm{ T}} <3 {\mathrm{\,GeV\!/}c} $ and $2.5<y^*<3.0$.

Fig1a.pdf [28 KiB]
HiDef png [436 KiB]
Thumbnail [104 KiB]
*.C file
Fig1a.pdf
Fig1b.pdf [33 KiB]
HiDef png [339 KiB]
Thumbnail [96 KiB] *.C file
Fig1b.pdf

The (left) $M(K^\mp\pi^\pm)$ and (right) $\log_{10}(\chi^2_{\text{\rm IP}} ( D ^0 )) $ distributions and the fit result for the inclusive $ D ^0 $ mesons in the backward data sample in the kinematic range of $2< p_{\mathrm{ T}} <3 {\mathrm{\,GeV\!/}c} $ and $-4.0<y^*<-3.5$.

Fig2a.pdf [28 KiB]
HiDef png [646 KiB]
Thumbnail [120 KiB]
*.C file
Fig2a.pdf
Fig2b.pdf [33 KiB]
HiDef png [436 KiB]
Thumbnail [106 KiB] *.C file
Fig2b.pdf

Double-differential cross-section $\frac{\mathrm{d}^2\sigma}{\mathrm{d} p_{\mathrm T}\mathrm{d} y^*}$ (mb/( $ {\mathrm{\,GeV\!/}c}$ )) of prompt $ D ^0 $ meson production in $ p\mathrm{Pb} $ collisions in the (left) forward and (right) backward collision samples. The uncertainty is the quadratic sum of the statistical and systematic components.

Fig3a.pdf [16 KiB]
HiDef png [228 KiB]
Thumbnail [76 KiB]
*.C file
Fig3a.pdf
Fig3b.pdf [16 KiB]
HiDef png [204 KiB]
Thumbnail [74 KiB] *.C file
Fig3b.pdf

Differential cross-section of prompt $ D ^0 $ meson production in $ p\mathrm{Pb} $ collisions as a function of (left) $ p_{\mathrm{ T}} $ ($\frac{\mathrm{d}\sigma}{\mathrm{d} p_{\rm T}}$) and (right) $y^{*}$ ($\frac{\mathrm{d}\sigma}{\mathrm{d} y^*}$) in the forward and backward collision samples. The uncertainty is the quadratic sum of the statistical and systematic components. The measurements are compared with theoretical predictions including different nuclear parton distribution functions as explained in the text.

Fig4a.pdf [18 KiB]
HiDef png [356 KiB]
Thumbnail [91 KiB]
*.C file
Fig4a.pdf
Fig4b.pdf [31 KiB]
HiDef png [455 KiB]
Thumbnail [91 KiB] *.C file
Fig4b.pdf

Nuclear modification factor $R_{ p\mathrm{Pb} }$ as a function of $ p_{\mathrm{ T}} $ for prompt $ D ^0 $ meson production in the (left) backward data and (right) forward data, integrated over the common rapidity range $2.5<|y^{*}|<4.0$ for $ p_{\mathrm{ T}} <6 {\mathrm{\,GeV\!/}c} $ and over $2.5<|y^{*}|<3.5$ for $6< p_{\mathrm{ T}} <10 {\mathrm{\,GeV\!/}c} $. The uncertainty is the quadratic sum of the statistical and systematic components. The CGC predictions are only available for the forward region.

Fig5a.pdf [15 KiB]
HiDef png [301 KiB]
Thumbnail [78 KiB]
*.C file
Fig5a.pdf
Fig5b.pdf [16 KiB]
HiDef png [530 KiB]
Thumbnail [101 KiB] *.C file
Fig5b.pdf

Nuclear modification factor $R_{ p\mathrm{Pb} }$ as a function of $y^*$ for prompt $ D ^0 $ meson production, integrated up to $ p_{\mathrm{ T}} =10 {\mathrm{\,GeV\!/}c} $. The uncertainty is the quadratic sum of the statistical and systematic components.

Fig6.pdf [27 KiB]
HiDef png [453 KiB]
Thumbnail [96 KiB]
*.C file
Fig6.pdf

Ratio of nuclear modification factors $R_{ p\mathrm{Pb} }$ of $ { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} $ and $\psi {(2S)} $ to $ D ^0 $ mesons in bins of rapidity integrated up to $ p_{\mathrm{ T}} =10 {\mathrm{\,GeV\!/}c} $ in the common rapidity range $2.5<|y^{*}|<4.0$. The uncertainty is the quadratic sum of the statistical and systematic components.

Fig7.pdf [14 KiB]
HiDef png [112 KiB]
Thumbnail [40 KiB]
*.C file
Fig7.pdf

Forward-backward ratio $R_\mathrm{FB}$ for prompt $ D ^0 $ meson production (left) as a function of $ p_{\mathrm{ T}} $ integrated over the common rapidity range $2.5<|y^{*}|<4.0$ for $ p_{\mathrm{ T}} <6 {\mathrm{\,GeV\!/}c} $ and over $2.5<|y^{*}|<3.5$ for $6< p_{\mathrm{ T}} <10 {\mathrm{\,GeV\!/}c} $; (right) as a function of $y^*$ integrated up to $ p_{\mathrm{ T}} =10 {\mathrm{\,GeV\!/}c} $. The uncertainty is the quadratic sum of the statistical and systematic components.

Fig8a.pdf [16 KiB]
HiDef png [558 KiB]
Thumbnail [113 KiB]
*.C file
Fig8a.pdf
Fig8b.pdf [15 KiB]
HiDef png [491 KiB]
Thumbnail [103 KiB] *.C file
Fig8b.pdf

Relative forward-backward production ratio $R_\mathrm{FB}$ for prompt $ D ^0 $ mesons over that for prompt $ { J \mskip -3mu/\mskip -2mu\psi \mskip 2mu} $ mesons (left) as a function of $ p_{\mathrm{ T}} $ integrated over the common rapidity range $2.5<|y^{*}|<4.0$ for $ p_{\mathrm{ T}} <6 {\mathrm{\,GeV\!/}c} $ and over $2.5<|y^{*}|<3.5$ for $6< p_{\mathrm{ T}} <10 {\mathrm{\,GeV\!/}c} $; (right) as a function of $y^*$ integrated up to $ p_{\mathrm{ T}} =10 {\mathrm{\,GeV\!/}c} $. The red inner bars in the uncertainty represent the statistical uncertainty and the black outer bars the quadratic sum of the statistical and systematic components.

Fig9a.pdf [14 KiB]
HiDef png [120 KiB]
Thumbnail [46 KiB]
*.C file
Fig9a.pdf
Fig9b.pdf [13 KiB]
HiDef png [97 KiB]
Thumbnail [39 KiB] *.C file
Fig9b.pdf

Animated gif made out of all figures.

PAPER-2017-015.gif
Thumbnail
thumbnail_PAPER-2017-015.gif

Tables and captions

Summary of systematic and statistical uncertainties on the cross-section. The ranges indicate the variations between bins, with the uncertainty on average increasing with rapidity and momentum.

Table_1.pdf [60 KiB]
HiDef png [116 KiB]
Thumbnail [17 KiB]
tex code
Table_1.pdf

Double-differential cross-section $\frac{\mathrm{d}^2\sigma}{\mathrm{d} p_{\mathrm T}\mathrm{d} y^*}$ (mb/( $ {\mathrm{\,GeV\!/}c}$ )) for prompt $ D ^0 $ meson production as functions of $ p_{\mathrm{ T}} $ and $y^{*}$ in $ p\mathrm{Pb} $ forward and backward data, respectively. The first uncertainty is statistical, the second is the component of the systematic uncertainty that is uncorrelated between bins and the third is the correlated component. In the regions with no entries the signal is not statistically significant.

Table_2.pdf [46 KiB]
HiDef png [551 KiB]
Thumbnail [87 KiB]
tex code
Table_2.pdf

Measured differential cross-section $\frac{\mathrm{d}\sigma}{\mathrm{d} p_{\mathrm T}}$ (mb/( $ {\mathrm{\,GeV\!/}c}$ )) for prompt $ D ^0 $ meson production as a function of $ p_{\mathrm{ T}} $ in $ p\mathrm{Pb} $ forward and backward data, respectively. The first uncertainty is statistical, the second is the component of the systematic uncertainty that is uncorrelated between bins and the third is the correlated component. The results in the last two columns are integrated over the common rapidity range $2.5<|y^{*}|<4.0$ for $ p_{\mathrm{ T}} <6 {\mathrm{\,GeV\!/}c} $ and over $2.5<|y^{*}|<3.5$ for $6< p_{\mathrm{ T}} <10 {\mathrm{\,GeV\!/}c} $.

Table_3.pdf [46 KiB]
HiDef png [163 KiB]
Thumbnail [24 KiB]
tex code
Table_3.pdf

Differential cross-section $\frac{\mathrm{d}\sigma}{\mathrm{d} y^*}$ (mb) for prompt $ D ^0 $ meson production as a function of $|y^{*}|$ in $ p\mathrm{Pb} $ forward and backward data, respectively. The first uncertainty is statistical, the second is the component of the systematic uncertainty that is uncorrelated between bins and the third is the correlated component.

Table_4.pdf [45 KiB]
HiDef png [187 KiB]
Thumbnail [31 KiB]
tex code
Table_4.pdf

Nuclear modification factor $R_{ p\mathrm{Pb} }$ for prompt $ D ^0 $ meson production in different $ p_{\mathrm{ T}} $ ranges, integrated over the common rapidity range $2.5<|y^{*}|<4.0$ for $ p_{\mathrm{ T}} <6 {\mathrm{\,GeV\!/}c} $ and over $2.5<|y^{*}|<3.5$ for $6< p_{\mathrm{ T}} <10 {\mathrm{\,GeV\!/}c} $ for the forward (positive $y^*$) and backward (negative $y^*$) samples. The first uncertainty is statistical and the second systematic.

Table_5.pdf [36 KiB]
HiDef png [147 KiB]
Thumbnail [25 KiB]
tex code
Table_5.pdf

Nuclear modification factor $R_{ p\mathrm{Pb} }$ for prompt $ D ^0 $ meson production in different $y^*$ ranges, integrated up to $ p_{\mathrm{ T}} =10 {\mathrm{\,GeV\!/}c} $. The first uncertainty is statistical and the second systematic.

Table_6.pdf [47 KiB]
HiDef png [145 KiB]
Thumbnail [23 KiB]
tex code
Table_6.pdf

Forward-backward ratio $R_\mathrm{FB}$ for prompt $ D ^0 $ meson production in different $ p_{\mathrm{ T}} $ ranges, integrated over the common rapidity range $2.5<|y^{*}|<4.0$ for $ p_{\mathrm{ T}} <6 {\mathrm{\,GeV\!/}c} $ and over $2.5<|y^{*}|<3.5$ for $6< p_{\mathrm{ T}} <10 {\mathrm{\,GeV\!/}c} $, and in different $y^*$ ranges integrated up to $ p_{\mathrm{ T}} =10 {\mathrm{\,GeV\!/}c} $. The first uncertainty is the statistical and the second is the systematic component.

Table_7.pdf [42 KiB]
HiDef png [255 KiB]
Thumbnail [39 KiB]
tex code
Table_7.pdf

Supplementary Material [file]

Supplementary material full pdf

supple[..].pdf [56 KiB]
supplementary.pdf

This is the supplementary material for the paper LHCb-PAPER-2017-015, Study of prompt Dzero meson production in pPb collisions at sqrt(s)=5 TeV. It includes the following files: Fig10.png Fig10.pdf Fig10.eps Fig10.C supplementary.pdf

Fig10.pdf [14 KiB]
HiDef png [93 KiB]
Thumbnail [36 KiB]
*C file
Fig10.pdf

Created on 09 December 2018.Citation count from INSPIRE on 09 December 2018.