CMSPASHIN16007  
$\mathrm{D}^{0}$ meson $v_{n}$ harmonics in PbPb collisions at 5.02 TeV  
CMS Collaboration  
September 2016  
Abstract: The Fourier coefficients $v_{2}$ and $v_{3}$, which reflect the azimuthal anisotropy of $\mathrm{D}^{0}$ meson, is measured with scalarproduct method in PbPb collisions at $ \sqrt{s_\mathrm{NN}} = $ 5.02 TeV with CMS. The measurement is done in a wide $p_{\mathrm{T}}$ range up to 40 GeV/$c$, for centrality classes 010%, 1030% and 3050%. It is the first measurement on $\mathrm{D}^{0}$ $v_{3}$ and the uncertainties on $\mathrm{D}^{0}$ $v_{2}$ are significantly improved compared with previous measurements. The measured $\mathrm{D}^{0}$ $v_{n}$ (n = 2, 3) is consistent with charged particle $v_{n}$ in central collisions, and begins to be lower than charged particles $v_{n}$ in $p_{\mathrm{T}}$ range 1 to 6 GeV/$c$ for more peripheral collisions. In high $p_{\mathrm{T}}$ range, nonzero $\mathrm{D}^{0}$ $v_{2}$ is also observed, which indicates the path length dependent energy loss of charm quark.  
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These preliminary results are superseded in this paper, PRL 120 (2018) 202301. The superseded preliminary plots can be found here. 
Figures & Tables  Summary  Additional Figures  References  CMS Publications 

Figures  
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Figure 1:
Examples of simultaneous fit on mass spectrum and $v_{2}$ (top) or $v_{3}$ (bottom) as a function of invariant mass in selected ${p_{\mathrm {T}}}$ intervals. 
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Figure 1a:
Example of simultaneous fit on mass spectrum and $v_{2}$ as a function of invariant mass in selected ${p_{\mathrm {T}}}$ intervals. 
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Figure 1b:
Example of simultaneous fit on mass spectrum and $v_{2}$ as a function of invariant mass in selected ${p_{\mathrm {T}}}$ intervals. 
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Figure 1c:
Example of simultaneous fit on mass spectrum and $v_{3}$ as a function of invariant mass in selected ${p_{\mathrm {T}}}$ intervals. 
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Figure 1d:
Example of simultaneous fit on mass spectrum and $v_{3}$ as a function of invariant mass in selected ${p_{\mathrm {T}}}$ intervals. 
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Figure 2:
Prompt ${\mathrm {D}^{0}}$ fractions in raw ${\mathrm {D}^{0}}$ yield as function of ${p_{\mathrm {T}}}$ for centrality classes 010% (left), 1030% (middle) and 3050% (right) with all analysis cuts (red circles) and without $b_{0} < $ 0.008 cm cut (blue squares). 
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Figure 3:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ for centrality 010% (left), 1030% (middle) and 3050% (right). Charged particle $v_{2}$ [21] in the same centrality class is also plotted for comparison. 
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Figure 4:
Prompt ${\mathrm {D}^{0}}$ $v_{3}$ for centrality 010% (left), 1030% (middle) and 3050% (right). Charged particle $v_{3}$ [21] in the same centrality class is also plotted for comparison. 
Tables  
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Table 1:
Summary of systematic uncertainties for $v_{2}$ and $v_{3}$ for centrality class 3050%. Absolute uncertainties are assigned. 
Summary 
In summary, azimuthal anisotropy $v_2$ and $v_3$ of $\mathrm{D}^0$ is measured with scalarproduct method in PbPb collisions at $ \sqrt{s_\mathrm{NN}} = $ 5.02 TeV with CMS, which is the first measurement on $v_3$ of $\mathrm{D}^0$. To extract $v_2$ and $v_3$ of prompt $\mathrm{D}^0$, the systematic uncertainties from nonprompt $\mathrm{D}^0$ are studied in a data driven method. Prompt $\mathrm{D}^0$ $v_2$ is found to be positive in studied $p_{\mathrm{T}}$ range 1 to 40 GeV/$c$, and prompt $\mathrm{D}^0$ $v_3$ is also found to be positive in $p_{\mathrm{T}}$ range around 1 to 8 GeV/c. The measured prompt $\mathrm{D}^0$ $v_n$ ($n =$ 2, 3) is consistent with charged particle $v_n$ in central collisions, and is lower than $v_n$ of charged particles in $p_{\mathrm{T}}$ range 1 to 6 GeV/$c$ for more peripheral collisions. 
Additional Figures  
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Additional Figure 1:
Mass spectrum fit in ${p_{\mathrm {T}}}$ intervals 23 GeV/$c$ (a) and 2040 GeV/$c$ (b) for centrality 010%. 
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Additional Figure 1a:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 23 GeV/$c$ for centrality 010%. 
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Additional Figure 1b:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 2040 GeV/$c$ for centrality 010%. 
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Additional Figure 2:
Mass spectrum fit in ${p_{\mathrm {T}}}$ intervals 12 GeV/$c$ (a), 23 GeV/$c$ (b) and 2040 GeV/$c$ (c) for centrality 1030%. 
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Additional Figure 2a:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 12 GeV/$c$ for centrality 1030%. 
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Additional Figure 2b:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 23 GeV/$c$ for centrality 1030%. 
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Additional Figure 2c:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 2040 GeV/$c$ for centrality 1030%. 
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Additional Figure 3:
Mass spectrum fit in ${p_{\mathrm {T}}}$ intervals 12 GeV/$c$ (a), 23 GeV/$c$ (b) and 2040 GeV/$c$ (c) for centrality 3050%. 
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Additional Figure 3a:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 12 GeV/$c$ for centrality 3050%. 
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Additional Figure 3b:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 23 GeV/$c$ for centrality 3050%. 
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Additional Figure 3c:
Mass spectrum fit in ${p_{\mathrm {T}}}$ interval 2040 GeV/$c$ for centrality 3050%. 
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Additional Figure 4:
Example of template fit on impact parameter distributions to evaluate prompt ${\mathrm {D}^{0}}$ fraction in PbPb collisions in ${p_{\mathrm {T}}}$ interval 56 GeV/$c$ for centrality 1030%. 
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Additional Figure 5:
Example of $\mathrm{d}^{2}N$/($\mathrm{d} {p_{\mathrm {T}}} \mathrm{d} \Delta \phi $) fit for $v_{2}^{obs}$ with $\Delta \phi $ bins method in ${p_{\mathrm {T}}}$ interval 56 GeV/$c$ for centrality 1030%. 
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Additional Figure 6:
Prompt ${\mathrm {D}^{0}}$ fractions for centrality 010% (left), 1030% (middle) and 3050% (right) with all analysis cuts. 
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Additional Figure 7:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ for centrality 010% (left), 1030% (middle) and 3050% (right). 
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Additional Figure 8:
Prompt ${\mathrm {D}^{0}}$ $v_{3}$ for centrality 010% (left), 1030% (middle) and 3050% (right). 
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Additional Figure 9:
${\mathrm {D}^{0}}$ $v_{2}$ from SP method and $\Delta \phi $ bins method for centrality 010% (left), 1030% (middle) and 3050% (right). 
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Additional Figure 10:
${\mathrm {D}^{0}}$ $v_{3}$ from SP method and $\Delta \phi $ bins method for centrality 010% (left), 1030% (middle) and 3050% (right). 
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Additional Figure 11:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ for centrality 010% (left), 1030% (middle) and 3050% (right). Calculations from theoretical models (PRC 94 014909 (2016), PLB 735 (2014) 445, JHEP 1602 (2016) 169 and PRD 91 074027 (2015)) are plotted for comparison. Charged particle $v_{2}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 12:
Prompt ${\mathrm {D}^{0}}$ $v_{3}$ for centrality 010% (left), 1030% (middle) and 3050% (right). Calculations from LBT model (PRC 94 014909 (2016)) are plotted for comparison. Charged particle $v_{3}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 13:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ for centrality 010% (a), 1030% (b) and 3050% (c). Calculations from theoretical models (PRC 94 014909 (2016), PLB 735 (2014) 445, JHEP 1602 (2016) 169 and PRD 91 074027 (2015)) are plotted for comparison. Charged particle $v_{2}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 13a:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ for centrality 010%. Calculations from theoretical models (PRC 94 014909 (2016), PLB 735 (2014) 445, JHEP 1602 (2016) 169 and PRD 91 074027 (2015)) are plotted for comparison. Charged particle $v_{2}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 13b:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ for centrality 1030%. Calculations from theoretical models (PRC 94 014909 (2016), PLB 735 (2014) 445, JHEP 1602 (2016) 169 and PRD 91 074027 (2015)) are plotted for comparison. Charged particle $v_{2}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 13c:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ for centrality 3050%. Calculations from theoretical models (PRC 94 014909 (2016), PLB 735 (2014) 445, JHEP 1602 (2016) 169 and PRD 91 074027 (2015)) are plotted for comparison. Charged particle $v_{2}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 14:
Prompt ${\mathrm {D}^{0}}$ $v_{3}$ for centrality 010% (a), 1030% (b) and 3050% (c). Calculations from LBT model (PRC 94 014909 (2016)) are plotted for comparison. Charged particle $v_{3}$ in the same centrality class is also plotted for comparison. 
png pdf 
Additional Figure 14a:
Prompt ${\mathrm {D}^{0}}$ $v_{3}$ for centrality 010%. Calculations from LBT model (PRC 94 014909 (2016)) are plotted for comparison. Charged particle $v_{3}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 14b:
Prompt ${\mathrm {D}^{0}}$ $v_{3}$ for centrality 1030%. Calculations from LBT model (PRC 94 014909 (2016)) are plotted for comparison. Charged particle $v_{3}$ in the same centrality class is also plotted for comparison. 
png pdf 
Additional Figure 14c:
Prompt ${\mathrm {D}^{0}}$ $v_{3}$ for centrality 3050%. Calculations from LBT model (PRC 94 014909 (2016)) are plotted for comparison. Charged particle $v_{3}$ in the same centrality class is also plotted for comparison. 
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Additional Figure 15:
Prompt ${\mathrm {D}^{0}}$ $v_{2}$ compared with ALICE results (PRC 90 (2014) 034904) for centrality 010% (left), 1030% (middle) and 3050% (right). 
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