d meson production in heavy ion collisions in cms experiment · jing wang (mit), d0 meson...
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Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 1
D0 Meson Production in Heavy Ion Collisions in CMS experiment
Jing Wang on behalf of the CMS Collaboration
The 16th International Conference on Strangeness in Quark Matter 27 June - 1 July 2016
Berkeley (United States)
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley)
• Two energy loss mechanisms: Collisional + Radiative• Flavor-dependent
• Dead cone effect [1] (Radiative energy loss is suppressed at small angels)
• Expect: ΔElight > ΔEc > ΔEb
• Nuclear modification factor: • RlightAA < RDAA < RBAA
• Dead cone effect is expected to be important at low pT
2
Why studying heavy flavors in HI?Heavy quarks are produced via initial hard scatterings• Carry information about the system at early stage → Good probe of QGP
In-medium energy lossthe probe heavy quarks interact with the medium
?
[1] Y.L. Dokshitzer, D. E. Kharzeev, Phys. Lett. B 519 (2001) 199.
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley)
(GeV/c)T
p0 5 10 15 20 25 30 35 40
AA ,
RAA
R*
0
0.2
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1
1.2
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1.6
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, CMS PreliminaryAA R*0Prompt D|y| < 1.0, Cent. 0-20%Syst. PbPb dataErr. pp reference
(JHEP 09 (2012) 112), Alice AA R0Prompt D|y| < 0.5, Cent. 0-20%Syst.
Filled markers: data-extrapolated referenceOpen markers: FONLL reference
= 2.76 TeVNNsPbPb
3
D0 measurements with CMS in Run IPbPb @ 2.76 TeV
CMS-PAS-HIN-15-005
• Dataset: MB events• pT: 2-40 GeV/c• pp reference: data-extrapolated
and FONLL
Run II 5.02 TeV• pT: 2-100 GeV/c• pp reference: direct data
Measurements reaching very high pT for the first time!
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 4
D0 meson production at 5.02 TeV
CMS-PAS-HIN-16-001First Run II heavy flavor analysis
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 5
D0 meson production
• c→D0: O(50%) of c cross-section• D0→Kπ: 3.93 ± 0.04%• D0 cτ = 122.9 µm D0
Primary vertex
Secondary vertex
Kπ
D0
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 6
D0 measurements in pp and PbPbD0→Kπ in pp and PbPb collisions at 5.02TeV, Centrality 0-10% and 0-100%, |y|<1
Datasets• Low pT ( < 20 GeV/c)
MinBias Events (pp: 2 billions events; PbPb: 150 million events)• High pT ( > 20 GeV/c)
Events triggered by dedicated HLT D0 filters to enhance the statistics at very high pT
(GeV/c)T
p0D10 20 30 40 50 60 70 80 90 100
HLT
D m
eson
trig
ger e
ffici
ency
0
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1.4
> 20T
trigger p0D> 40
T trigger p0D
> 60T
trigger p0D
(5.02 TeV PbPb)-1
bµ404 CMSPerformance
) (GeV)0 (DT
p0 10 20 30 40 50 60
HLT
Effi
cien
cy
0
0.2
0.4
0.6
0.8
1
1.2
1.4
8≥ T
HLT D meson p15≥
THLT D meson p
20≥ T
HLT D meson p 30≥
THLT D meson p
= 5.02 TeV s pp,
CMSPreliminary
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 7
High-Level-Trigger (HLT) D0 triggers
Hardware L1 jet triggers selection
Track selection in software triggers D0 selection
K
π
D0 decayvertex
Primaryvertex
• Level-1 (L1) jet algorithm with online background subtraction
Track seed pT cut applied:• pT > 2 GeV for pp • pT > 8 GeV for PbPb
• D0 online reconstruction• loose selection based on
D0 vertex displacement
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 8
High-Level-Trigger (HLT) D0 triggers
Hardware L1 jet triggers selection
Track selection in software triggers D0 selection
K
π
D0 decayvertex
Primaryvertex
• Level-1 (L1) jet algorithm with online background subtraction
Track seed pT cut applied:• pT > 2 GeV for pp • pT > 8 GeV for PbPb
• D0 online reconstruction• loose selection based on
D0 vertex displacement)2 (GeV/cKπm
1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
/ (5
MeV
/c
0
10
20
30
40
50DataFit
Signal0D+0D swappedπK-
Combinatorial
PreliminaryCMS = 5.02 TeVNNspp
< 200.0 GeV/cT
100.0 < p|y| < 1.0
• 5.02 TeV pp collisions• Extend to D0 high pT to 200
GeV/c
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 9
D0 measurements in pp and PbPbD0→Kπ in pp and PbPb collisions at 5.02TeV, Centrality 0-10% and 0-100%, |y|<1
Analysis strategy• Primary vertex reconstruction several tracks• D0 candidates (vertex) reconstruction pairing two tracks + kinematic fitter• D0 candidates selection (TMVA) decay topology
• Pointing angel (α) < ~0.12• 3D decay length (d0) normalized by its error > ~4• Secondary vertex probability > ~0.1
• Raw yields extraction Invariant mass• Cross-sections
Primaryvertex
Secondaryvertex
d0
pD α
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 10
Invariant mass spectra in pp (5.02 TeV)Raw yields extraction
Mass distributions fitted by• Double gaussian (Signal)• 3rd order polynomial (Combinatorial)• Single gaussian (K-π swapped)
No PIDCandidates with wrong mass assignment
)2 (GeV/cKπm1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
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MeV
/c
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2500
3000DataFit
Signal0D+0D swappedπK-
Combinatorial
PreliminaryCMS = 5.02 TeVNNspp
< 6.0 GeV/cT
5.0 < p|y| < 1.0
Fix in MC
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 11
Obtain cross-section from raw yieldsRaw yields → Cross-sections
Prompt D0 Cross-section Raw yields
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 12
Obtain cross-section from raw yieldsRaw yields → Cross-sections
Acceptance & efficiency
Trigger efficiency
(GeV/c)T
p0 20 40 60 80 100
sel
∈ x
re
co∈
x
α
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1 PreliminaryCMS = 5.02 TeVNNspp
PromptNon-prompt
(GeV/c)T
p0D10 20 30 40 50 60 70 80 90 100
HLT
D m
eson
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ger e
ffici
ency
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trigger p0D> 40
T trigger p0D
> 60T
trigger p0D
(5.02 TeV PbPb)-1
bµ404 CMSPerformance
from MC simulation fit turn on curve
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 13
Obtain cross-section from raw yieldsRaw yields → Cross-sections
Fraction of prompt D0
Branching fraction
Luminosity
Prompt: D0 mesons coming from c-quark fragmentation
B D0
X
K
π
Prompt:
Non-prompt:
c D0
K
π
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 14
fprompt: Fraction of prompt D0
DCA (cm)0D0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
)-1
DC
A) (c
m0
dN /
d(D
310
410
510
CMS Preliminary = 5.02 TeVNNspp
< 12.5 GeV/c |y| < 1.0T
10.0 < p
2.4 %±Prompt frac. = 76.7
Data0Prompt D
0Non-Prompt D
• Different shapes of distance of closest approach (DCA) distributions of prompt and non-prompt D0
• The shapes of DCA distributions come from MC
• Fit DCA distributions of data
α
D0 DCA
D0 flight distance
B D0
X
K
π
D0 DCA = flight distance * sin(α)
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 15
fprompt: Fraction of prompt D0
DCA (cm)0D0 0.01 0.02 0.03 0.04 0.05 0.06 0.07
)-1
DC
A) (c
m0
dN /
d(D
310
410
510
CMS Preliminary = 5.02 TeVNNspp
< 12.5 GeV/c |y| < 1.0T
10.0 < p
2.4 %±Prompt frac. = 76.7
Data0Prompt D
0Non-Prompt D
(GeV/c)T
p0D0 20 40 60 80 100
Frac
tion
0
0.1
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0.3
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1 PreliminaryCMS = 5.02 TeVNNsPP
|y| < 1.0PromptNon-prompt
fprompt vs. D0 pT
• Consistent with that from FONLL convoluted with MC efficiency
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 16
pT-differential cross-section in pp
• The first measurement of D0 cross-section in pp collisions at 5.02 TeV
• pT range covers from 2 to 100 GeV/c in |y| < 1
• Consistent with the upper bound of FONLL predictions [1]
10 210
c)-1( p
b G
eVT
/ dp
σd
10
210
310
410
510
610
710
810
910
1010
|y| < 1.0
Global uncert. 12.1%
dataFONLL pp ref.
(5.02 TeV pp)-125.8 pb
CMSPreliminary
(GeV/c)T
p10 210
Dat
a / F
ON
LL
00.5
11.5
22.5
[1] M. Cacciari, M. Greco, P. Nason, “The pT Spectrum in Heavy-Flavour Hadroproduction”, JHEP 007, 9805 (1998)
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 17
Invariant mass spectra in PbPbRaw yields extraction
)2 (GeV/cKπm1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
/ (5
MeV
/c
0
20
40
60
80
100
120
140
160
180
200
220DataFit
Signal0D+0D swappedπK-
Combinatorial
PreliminaryCMS = 5.02 TeVNNsPbPb
< 30.0 GeV/cT
25.0 < p
Centrality 0-100%
|y| < 1.0
5.02 TeV, 0-100%
)2 (GeV/cKπm1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
/ (5
MeV
/c
0
5000
10000
15000
20000
25000
30000
35000
40000 DataFit
Signal0D+0D swappedπK-
Combinatorial
PreliminaryCMS = 5.02 TeVNNsPbPb
< 6.0 GeV/cT
5.0 < p
Centrality 0-100%
|y| < 1.0
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 18
Systematic uncertainties summary
(GeV/c)T
p0D1 10
210
Syst
emat
ical
Unc
erta
inty
-0.6
-0.4
-0.2
0
0.2
0.4
0.6 (5.02 TeV PbPb)
-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPerformance , |y| < 1
AA R0D
Centrality 0-100%
, Lumi)MB
Overall Normalization (NTotal SystematicsSignal ExtractionD Meson Selection and CorrectionB feed down subtraction
Signal extraction systematics ~5%• Varying signal and background fit
functions
D meson selection ~13%• Comparing data and MC driven
efficiencies of the different cut selections
• Systematics on trigger efficiency • Tracking efficiency systematic
(evaluated by 2 and 4 prongs D0 decays)
B-feed down uncertainty ~8%• Obtained by comparing fprompt
estimation with alternative method based on decay length and FONLL predictions
PbPb, Centrality 0-100%
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 19
D0 RAA in PbPb collisions at 5.02 TeV
• Strong suppression at pT 5-8 GeV/c• Less suppression for low and high pT
|y| < 1, Centrality 0-100%
CMS-PAS-HIN-16-001
(GeV/c)T
p1 10 210
AA R0 D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
(5.02 TeV PbPb)-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPreliminary
Centrality 0-100%|y| < 1
0 DAAR
and lumi.AATuncertainty
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 20
D0 RAA in PbPb collisions at 5.02 TeV
• Comparison with charged hadrons [1]• Less suppression at low pT• Similar suppression at high pT
|y| < 1, Centrality 0-100%
[1] CMS-PAS-HIN-15-015CMS-PAS-HIN-16-001
(GeV/c)T
p1 10 210
AA R0 D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
(5.02 TeV PbPb)-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPreliminary
Centrality 0-100%|y| < 1
0 DAAR
charged hadronsAAR and lumi.AAT
uncertainty
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 21
D0 RAA in PbPb collisions at 5.02 TeV
• Comparison with charged hadrons [1]• Less suppression at low pT• Similar suppression at high pT
• Comparison with theoretical predictions• S. Cao et al. [2] (Improved Langevin
eq, Linearized Boltzmann)• M. Djordjevic [3] (pQCD calculations in
a finite size optically thin dynamical QCD medium)
|y| < 1, Centrality 0-100%
[1] CMS-PAS-HIN-15-015
[2] arXiv:1605.06447v1.
[3] Phys. Rev. C 92 (Aug, 2015) 024918
CMS-PAS-HIN-16-001
(GeV/c)T
p1 10 210
AA R0 D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
(5.02 TeV PbPb)-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPreliminary
Centrality 0-100%|y| < 1
0 DAAR
charged hadronsAAR
S. Cao et al. 0-80%
M. Djordjevic and lumi.AAT
uncertainty
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 22
D0 RAA in PbPb collisions at 5.02 TeV
CMS-PAS-HIN-16-001 (GeV/c)
Tp
1 10 210
AA R0 D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
(5.02 TeV PbPb)-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPreliminary
Centrality 0-100%|y| < 1
0 DAAR
and lumi.AATuncertainty
(GeV/c)T
p1 10 210
AA R0 D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
(5.02 TeV PbPb)-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPreliminary
Centrality 0-10%|y| < 1
0 DAAR
and lumi.AATuncertainty
Centrality 0-100% Centrality 0-10%
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 23
D0 RAA in PbPb collisions at 5.02 TeV
• Comparison with charged hadrons [1]• Similar behavior with 0-100%
|y| < 1, Centrality 0-10%
CMS-PAS-HIN-16-001[1] CMS-PAS-HIN-15-015
(GeV/c)T
p1 10 210
AA R0 D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
(5.02 TeV PbPb)-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPreliminary
Centrality 0-10%|y| < 1
0 DAAR
charged hadronsAAR and lumi.AAT
uncertainty
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 24
D0 RAA in PbPb collisions at 5.02 TeV
• Comparison with charged hadrons [1]• Similar behavior with 0-100%
• Comparison with theoretical predictions• S. Cao et al. [2] (Improved Langevin eq,
Linearized Boltzmann)• M. Djordjevic [3] (pQCD calculations in
a finite size optically thin dynamical QCD medium)
• CUJET3.0 [4] (jet quenching model based on DGLV opacity expansion theory)
• PHSD [5] (Parton-Hadron-String Dynamics transport approach)
• I. Vitev [6] (jet propagation in matter, soft-collinear effective theory with Glauber gluons (SCETG))
|y| < 1, Centrality 0-10%
CMS-PAS-HIN-16-001[1] CMS-PAS-HIN-15-015
[2] arXiv:1605.06447v1.
[3] Phys. Rev. C 92 (Aug, 2015) 024918
[4] JHEP 02 (2016) 169
[5] Phys. Rev. C 93 (Mar, 2016) 034906
[6] Phys. Rev. D 93 (Apr, 2015) 074030
(GeV/c)T
p1 10 210
AA R0 D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
(5.02 TeV PbPb)-1bµ (5.02 TeV pp) + 404 -125.8 pb
CMSPreliminary
Centrality 0-10%|y| < 1
0 DAAR charged hadronsAAR
M. Djordjevic0CUJET3.0 D
S. Cao et al.PHSD w/ shadowing PHSD w/o shadowing I.Vitev (g=1.8-2.0)
and lumi.AATuncertainty
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 25
Summary
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 26
Summary
D0 and charged particle RAA agree up to very high pT• Putting strong constraints on theoretical calculations• Forcing theories to describe HF production in a much
wider kinematic range where different processes dominate
Conclusions
Outlook• D meson at very low pT
• Down to ~1 GeV/c• The hadronization mechanisms and the cold
medium properties• D meson vn measurements
• Collective behavior • B meson RAA
• Coming soon!
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 27
Back up
Thanks for your attention!
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 28
D0 measurements with CMS in Run IPbPb @ 2.76 TeV
(GeV/c)T
p0 5 10 15 20 25 30 35 40
AA ,
RAA
R*
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
, CMS PreliminaryAA R*0Prompt D|y| < 1.0, Cent. 0-20%Syst. PbPb dataErr. pp reference
(JHEP 09 (2012) 112), Alice AA R0Prompt D|y| < 0.5, Cent. 0-20%Syst.
Filled markers: data-extrapolated referenceOpen markers: FONLL reference
= 2.76 TeVNNsPbPb
partN0 50 100 150 200 250 300 350 400
AA ,
RAA
R*
0
0.2
0.4
0.6
0.8
1
1.2
1.4AA R*0Prompt D
< 16.0 GeV/c, |y| < 1.0T
8.0 < p
PbPb data+Syst.+BRMB+NAAT
Err. pp reference
AA Rψ J/Non-prompt < 30.0 GeV/c, |y| < 1.2
T6.5 < p
Total Syst.
AA R particleCharged| < 1.0η < 9.6 GeV/c, |
T7.2 < pCMS, EPJC 72 (2012) 1945Total Syst.
CMS Preliminary = 2.76 TeVNNsPbPb
(GeV/c)T
p0 5 10 15 20 25
CP
R
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0-10% / 50-100%10-30% / 50-100%30-50% / 50-100%
PreliminaryCMS = 2.76 TeVNNsPbPb
|y| < 1.0
RAA vs. pT
CMS-PAS-HIN-15-005
RAA vs. Npart RCP vs. pT
• Measurements reaching very high pT (>100GeV/c) for the first time!• PP reference directly from data
RunII: pp + PbPb @ 5.02 TeV
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 29
Comparison with CMS 2.76 TeVPbPb 0-100%
(GeV/c)T
p1 10
210
AA R0
D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6 (5.02 TeV PbPb)
-1bµ (5.02 TeV pp) + 404
-125.8 pb
CMS PreliminaryCMS, 5.02 TeV, |y|<1CMS, 2.76 TeV, |y|<1CMS, 5.02 TeV, |y|<1CMS, 2.76 TeV, |y|<1
and lumi.AA
Tuncertainty
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 30
Comparison with ALICE 5.02 TeV
(GeV/c)T
p1 10
210
AA R0
D
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6 (5.02 TeV PbPb)
-1bµ (5.02 TeV pp) + 404
-125.8 pb
CMS PreliminaryCMS, 5.02 TeV, |y|<1ALICE, 2.76 TeV, |y|<0.5CMS, 5.02 TeV, |y|<1ALICE, 2.76 TeV, |y|<0.5
and lumi.AA
Tuncertainty
PbPb 0-10%
CMS: 0-10%, ALICE: 0-7.5%
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 31
Heavy flavor measurements with CMS
partN0 50 100 150 200 250 300 350 400
AAR
0
0.2
0.4
0.6
0.8
1
1.2
1.4
|y|<1.21.2<|y|<1.61.6<|y|<2.4
CMS Preliminary = 2.76 TeVNNsPbPb
ψNon-prompt J/
<30 GeV/cT
6.5<p
(GeV/c)T
p0 5 10 15 20 25 30 35 40
AA ,
RAA
R*
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
, CMS PreliminaryAA R*0Prompt D|y| < 1.0, Cent. 0-20%Syst. PbPb dataErr. pp reference
(JHEP 09 (2012) 112), Alice AA R0Prompt D|y| < 0.5, Cent. 0-20%Syst.
Filled markers: data-extrapolated referenceOpen markers: FONLL reference
= 2.76 TeVNNsPbPb
LHC Run I 2.76 PbPb + 5.02 pPb
1. b-jet RAA in PbPb2. J/ψ RAA in PbPb3. D0 meson RAA in PbPb4. B meson RpPb in pPb
① ② ③ ④
[1] Phys. Rev. Lett. 113, 132301 (2014)[2] CMS-PAS-HIN-12-014[3] CMS-PAS-HIN-15-005[4] Phys. Rev. Lett. 116, 032301 (2016)
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 32
CMS detector
Muon HCAL ECAL
Tracker |η|< 2.5
|η|< 3.0
|η|< 5.2
|η|< 2.4
Inner tracker: charged particles
EM and hadronic calorimeters Photons, Jet
Muon detectors
Forward Calorimeter: MB triggers, centrality
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 33
Mass spectra
)2 (GeV/cKπm1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
/ (5
MeV
/c
0
500
1000
1500
2000
2500
3000DataFit
Signal0D+0D swappedπK-
Combinatorial
PreliminaryCMS = 5.02 TeVNNspp
< 6.0 GeV/cT
5.0 < p|y| < 1.0
)2 (GeV/cKπm1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
/ (5
MeV
/c
0
100
200
300
400
500
600
700
800 DataFit
Signal0D+0D swappedπK-
Combinatorial
PreliminaryCMS = 5.02 TeVNNspp
< 30.0 GeV/cT
25.0 < p|y| < 1.0
pp
Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley)
)2 (GeV/cKπm1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
/ (5
MeV
/c
0
5000
10000
15000
20000
25000
30000
35000
40000 DataFit
Signal0D+0D swappedπK-
Combinatorial
PreliminaryCMS = 5.02 TeVNNsPbPb
< 6.0 GeV/cT
5.0 < p
Centrality 0-100%
|y| < 1.0
34
Mass spectraPbPb 0-100%
)2 (GeV/cKπm1.7 1.75 1.8 1.85 1.9 1.95 2
)2En
tries
/ (5
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Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 35
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Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 36
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Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 37
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Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 38
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Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 39
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Jing Wang (MIT), D0 meson production in HI collisions in CMS, SQM 2016 (Berkeley) 40
Heavy flavor measurements with CMS
b-jet RAA in PbPb B meson RpPb in pPb J/ψ RAA in PbPb
LHC Run I (2.76 PbPb + 5.02 pPb)
Phys. Rev. Lett. 113, 132301 (2014)
Phys. Rev. Lett. 116, 032301 (2016) CMS-PAS-HIN-12-014
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