Observation of double charm production involving open charm in pp collisions at $\sqrt{s}$=7 TeV
R. Aaij
,
I. de Bonis
(1)
,
D. Decamp
(1)
,
Ph. Ghez
(1)
,
P. Hopchev
(1)
,
J.-P. Lees
(1)
,
I.V. Machikhiliyan
(1)
,
M.-N. Minard
(1)
,
B. Pietrzyk
(1)
,
S. t'Jampens
(1)
,
V. Tisserand
(1)
,
E. Tournefier
(1)
,
S. Barsuk
(2)
,
O. Callot
(2)
,
J. He
(2)
,
B. Jean-Marie
(2)
,
J. Lefrançois
(2)
,
F. Machefert
(2)
,
A. Martin Sanchez
(2)
,
M. Nicol
(2)
,
P. Robbe
(2)
,
M.-H. Schune
(2)
,
B. Viaud
(2)
,
I. Videau
(2)
,
Ziad Zj Ajaltouni
(3)
,
O. Deschamps
(3)
,
Pierre Henrard
(3)
,
Marwa Jahjah-Hussein
(3)
,
R. Lefèvre
(3)
,
L. Li Gioi
(3)
,
S. Monteil
(3)
,
V. Niess
(3)
,
Pascal Perret
(3)
,
Diego Alejandro Roa Romero
(3)
,
Krzysztof Grzegorz Sobczak
(3)
,
C. Adrover
(4)
,
E. Aslanides
(4)
,
J. Cogan
(4)
,
B. Khanji
(4)
,
R. Legac
(4)
,
O. Leroy
(4)
,
G. Mancinelli
(4)
,
E. Maurice
(4)
,
M. Perrin-Terrin
(4)
,
M. Sapunov
(4)
,
J. Serrano
(4)
,
A. Tsaregorodtsev
(4)
R. Aaij
- Function : Author
S. t'Jampens
- Function : Author
- PersonId : 736045
- IdHAL : stephane-tjampens
- ORCID : 0000-0003-4249-6641
J. He
- Function : Author
- PersonId : 756138
- ORCID : 0000-0001-8179-417X
Ziad Zj Ajaltouni
- Function : Author
- PersonId : 903794
O. Deschamps
- Function : Author
- PersonId : 12089
- IdHAL : olivier-deschamps
- ORCID : 0000-0002-7047-6042
- IdRef : 161447368
Pierre Henrard
- Function : Author
- PersonId : 829303
Pascal Perret
- Function : Author
- PersonId : 739797
- IdHAL : pascal-perret
- ORCID : 0000-0002-5732-4343
Diego Alejandro Roa Romero
- Function : Author
- PersonId : 769524
- IdRef : 172096839
J. Cogan
- Function : Author
- PersonId : 750510
- IdHAL : julien-cogan
- ORCID : 0000-0001-7194-7566
- IdRef : 078779014
O. Leroy
- Function : Author
- PersonId : 171866
- IdHAL : olivier-leroy
- ORCID : 0000-0002-2589-240X
- IdRef : 169871835
M. Perrin-Terrin
- Function : Author
- PersonId : 741779
- IdHAL : perrin-terrin
- ORCID : 0000-0002-3568-1956
- IdRef : 179269666
J. Serrano
- Function : Author
- PersonId : 175327
- IdHAL : justine-serrano
- ORCID : 0000-0003-2489-7812
- IdRef : 127525521
Abstract
The production of $J/\psi$ mesons accompanied by open charm, and of pairs of open charm hadrons are observed in pp collisions at a centre-of-mass energy of 7 TeV using an integrated luminosity of $355pb^{-1}$ collected with the LHCb detector. Model independent measurements of absolute cross-sections are given together with ratios to the measured $J/\psi$ and open charm cross-sections. The properties of these events are studied and compared to theoretical predictions.