Measurement of the shape of the b quark fragmentation function using charmed mesons produced inside b jets from $\mathrm{t}\bar{\mathrm{t}}$ pair decays - INSPIRE

DataBETA

Measurement of the shape of the b quark fragmentation function using charmed mesons produced inside b jets from $\mathrm{t}\bar{\mathrm{t}}$ pair decays

CMS

Collaboration

2021

17 pages

Published: 2021

Report number:

CMS-PAS-TOP-18-012

Experiments:

CERN-LHC-CMS,
CERN-LHC-CMS

View in:

CERN Document Server

reference search10 citations

Citations per year

Abstract: (CDS)

A determination of the shape parameter of the Lund-Bowler fragmentation function for b quarks is presented. The analysis uses charm mesons produced inside b jets from

\mathrm{t}\bar{\mathrm{t}}

pair decays in a data sample collected by the CMS experiment at the LHC at

\sqrt{s}=13~\mathrm{TeV}

, corresponding to an integrated luminosity of

35.9~\mathrm{fb}^{-1}

. Samples of D

^{0}

and J/

\psi

mesons are reconstructed from the decays D

^{0} \to

K

^{\pm} \pi^{\mp}

and J/

\psi \to \mu^{+}\mu^{-}

using charged particle track information. The reconstructed mesons are used as proxies for their parent B hadrons. The corresponding

x_{b}

distributions, where

x_{b}

is the fraction of the total transverse momentum of the charged constituents of the jet carried by the charm meson, are fitted to extract the value of the fragmentation function shape parameter,

r_{b}

. A value of

r_{b}= 0.858 \pm 0.037 (\mathrm{stat}) \pm 0.031 (\mathrm{syst})

is obtained. This is the first measurement of the b quark fragmentation function in

\mathrm{t}\bar{\mathrm{t}}

events at the LHC, and significantly improves the experimental constraints on the shape of the function. From a comparison with results at the Z pole in e

^{+}

e

^{-}

data, no evidence for an environmental dependence of the fragmentation function is observed.

Note:

Preliminary results

Monte-Carlo
p p: scattering
p p: colliding beams
tau: pair production
bottom: fragmentation function
jet: bottom
charged particle: tracks
CERN LHC Coll
D0: hadronic decay
J/psi(3100): leptonic decay

References(42)

Figures(13)

[1]

Scaling Violations in Inclusive e+ e- Annihilation Spectra

- Phys.Rev.D 27 (1983) 105
•
DOI:
- 10.1103/PhysRevD.27.105

[2]

A General Model for Jet Fragmentation

- Z.Phys.C 20 (1983) 317
•
DOI:
- 10.1007/BF01407824

[3]

e+ e- Production of Heavy Quarks in the String Model

M.G. Bowler
(
- Oxford U.
)

- Z.Phys.C 11 (1981) 169,
- Z. Phys. C11 ( 1981) 169-174 and Oxford Univ. - 81-31 (81,REC.MAY) 18p
•
DOI:
- 10.1007/BF01574001

[4]

Study of the fragmentation of b quarks into B mesons at the Z peak

ALEPH

Collaboration

•

A. Heister
(
- Aachen, Tech. Hochsch.
)

et al.

- Phys.Lett.B 512 (2001) 30-48
•
e-Print:
- hep-ex/0106051
•
DOI:
- 10.1016/S0370-2693(01)00690-6

[5]

Inclusive analysis of the b quark fragmentation function in Z decays at LEP

OPAL

Collaboration

•

G. Abbiendi

et al.

- Eur.Phys.J.C 29 (2003) 463-478
•
e-Print:
- hep-ex/0210031
•
DOI:
- 10.1140/epjc/s2003-01229-x

[6]

A study of the b-quark fragmentation function with the DELPHI detector at LEP I and an averaged distribution obtained at the Z Pole

DELPHI

Collaboration

•

J. Abdallah
(
- Paris U., VI-VII
)

et al.

- Eur.Phys.J.C 71 (2011) 1557
•
e-Print:
- 1102.4748
•
DOI:
- 10.1140/epjc/s10052-011-1557-x

[7]

Measurement of the b quark fragmentation function in Z0 decays

SLD

Collaboration

•

Koya Abe

et al.

- Phys.Rev.D 65 (2002) 092006,
- Phys.Rev.D 66 (2002) 079905 (erratum)
•
e-Print:
- hep-ex/0202031
•
DOI:
- 10.1103/PhysRevD.66.079905

[8]

Measurement of the top quark mass using proton-proton data at ${\sqrt{(s)}}$ = 7 and 8 TeV

CMS

Collaboration

•

Vardan Khachatryan
(
- Yerevan Phys. Inst.
)

et al.

- Phys.Rev.D 93 (2016) 7, 072004
•
e-Print:
- 1509.04044
•
DOI:
- 10.1103/PhysRevD.93.072004

[9]

Measurement of the cross section ratio $\sigma_\mathrm{t \bar{t} b \bar{b}} / \sigma_\mathrm{t \bar{t} jj }$ in pp collisions at $\sqrt{s}$ = 8 TeV

CMS

Collaboration

•

Vardan Khachatryan
(
- Yerevan Phys. Inst.
)

et al.

- Phys.Lett.B 746 (2015) 132-153
•
e-Print:
- 1411.5621
•
DOI:
- 10.1016/j.physletb.2015.04.060

[10]

Search for standard model production of four top quarks in proton-proton collisions at $\sqrt{s}$ = 13 TeV

CMS

Collaboration

•

A.M. Sirunyan

et al.

- Phys.Lett.B 772 (2017) 336-358
•
e-Print:
- 1702.06164
•
DOI:
- 10.1016/j.physletb.2017.06.064

[11]

Event generator tunes obtained from underlying event and multiparton scattering measurements

CMS

Collaboration

•

Vardan Khachatryan
(
- Yerevan Phys. Inst.
)

et al.

- Eur.Phys.J.C 76 (2016) 3, 155
•
e-Print:
- 1512.00815
•
DOI:
- 10.1140/epjc/s10052-016-3988-x

[12]

Investigations of the impact of the parton shower tuning in Pythia 8 in the modelling of $\mathrm{t\overline{t}}$ at $\sqrt{s}=8$ and 13 TeV

CMS

Collaboration

[13]

Tuning PYTHIA 8.1: the Monash 2013 Tune

Peter Skands
(
- CERN
)
,
Stefano Carrazza
(
- Milan U. and
- INFN, Milan
)
,
Juan Rojo
(
- CERN and
- Oxford U., Theor. Phys.
)

- Eur.Phys.J.C 74 (2014) 8, 3024
•
e-Print:
- 1404.5630
•
DOI:
- 10.1140/epjc/s10052-014-3024-y

[14]

A New method for combining NLO QCD with shower Monte Carlo algorithms

Paolo Nason
(
- INFN, Milan
)

- JHEP 11 (2004) 040
•
e-Print:
- hep-ph/0409146
•
DOI:
- 10.1088/1126-6708/2004/11/040

[15]

Matching NLO QCD computations with Parton Shower simulations: the POWHEG method

Stefano Frixione
(
- INFN, Genoa
)
,
Paolo Nason
(
- INFN, Milan Bicocca
)
,
Carlo Oleari
(
- INFN, Milan Bicocca and
- Milan Bicocca U.
)

- JHEP 11 (2007) 070
•
e-Print:
- 0709.2092
•
DOI:
- 10.1088/1126-6708/2007/11/070

[16]

A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX

Simone Alioli
(
- DESY, Zeuthen and
- INFN, Milan Bicocca
)
,
Paolo Nason
(
- INFN, Milan Bicocca
)
,
Carlo Oleari
(
- Milan Bicocca U. and
- INFN, Milan Bicocca
)
,
Emanuele Re
(
- Durham U., IPPP and
- INFN, Milan Bicocca
)

- JHEP 06 (2010) 043
•
e-Print:
- 1002.2581
•
DOI:
- 10.1007/JHEP06(2010)043

[17]

Hadronic top-quark pair-production with one jet and parton showering

- JHEP 01 (2012) 137
•
e-Print:
- 1110.5251
•
DOI:
- 10.1007/JHEP01(2012)137

[18]

Top++: A Program for the Calculation of the Top-Pair Cross-Section at Hadron Colliders

Michal Czakon
(
- Aachen, Tech. Hochsch.
)
,
Alexander Mitov
(
- CERN
)

- Comput.Phys.Commun. 185 (2014) 2930
•
e-Print:
- 1112.5675
•
DOI:
- 10.1016/j.cpc.2014.06.021

[19]

Total Top-Quark Pair-Production Cross Section at Hadron Colliders Through $O(\alpha^4_S)$

- Phys.Rev.Lett. 110 (2013) 252004
•
e-Print:
- 1303.6254
•
DOI:
- 10.1103/PhysRevLett.110.252004

[20]

PYTHIA 6.4 Physics and Manual

Torbjorn Sjostrand
(
- Lund U., Dept. Theor. Phys.
)
,
Stephen Mrenna
(
- Fermilab
)
,
Peter Z. Skands
(
- Fermilab
)

- JHEP 05 (2006) 026
•
e-Print:
- hep-ph/0603175
•
DOI:
- 10.1088/1126-6708/2006/05/026

[21]

A Brief Introduction to PYTHIA 8.1

Torbjorn Sjostrand
(
- CERN and
- Lund U.
)
,
Stephen Mrenna
(
- Fermilab
)
,
Peter Z. Skands
(
- CERN and
- Fermilab
)

- Comput.Phys.Commun. 178 (2008) 852-867
•
e-Print:
- 0710.3820
•
DOI:
- 10.1016/j.cpc.2008.01.036

[22]

Parton distributions for the LHC Run II

NNPDF

Collaboration

•

Richard D. Ball
(
- U. Edinburgh, Higgs Ctr. Theor. Phys. and
- CERN
)

et al.

- JHEP 04 (2015) 040
•
e-Print:
- 1410.8849
•
DOI:
- 10.1007/JHEP04(2015)040

[23]

Review of Particle Physics

M. Tanabashi
(
- Nagoya U. and
- KMI, Nagoya
)
,
K. Hagiwara
(
- KEK, Tsukuba
)
,
K. Hikasa
(
- Tohoku U.
)
,
K. Nakamura
(
- Tokyo U., IPMU and
- KEK, Tsukuba
)
,
Y. Sumino
(
- Tohoku U.
)

et al.

- Phys.Rev.D 98 (2018) 3, 030001
•
DOI:
- 10.1103/PhysRevD.98.030001

[24]

The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations

J. Alwall
(
- Taiwan, Natl. Taiwan U.
)
,
R. Frederix
(
- CERN
)
,
S. Frixione
(
- CERN
)
,
V. Hirschi
(
- SLAC
)
,
F. Maltoni
(
- Louvain U., CP3
)

et al.

- JHEP 07 (2014) 079
•
e-Print:
- 1405.0301
•
DOI:
- 10.1007/JHEP07(2014)079

[25]

Comparative study of various algorithms for the merging of parton showers and matrix elements in hadronic collisions

et al.

- Eur.Phys.J.C 53 (2008) 473-500
•
e-Print:
- 0706.2569
•
DOI:
- 10.1140/epjc/s10052-007-0490-5

1-25 of 42
1
2
25 / page