Publications de Géraldine Conti

Application of vertex and mass constraints in track-based alignment

Olivier Schneider, Christophe Salzmann, Vincent Fave, Matthew Needham, Maurizio Martinelli, Frédéric Guillaume Dupertuis, Géraldine Conti, Louis Nicolas, Gerhard Raven

The software alignment of planar tracking detectors using samples of charged particle trajectories may lead to global detector distortions that affect vertex and momentum resolution. We present an alignment procedure that constrains such distortions by mak ...

Elsevier Science Bv2013

Absolute luminosity measurements with the LHCb detector at the LHC

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Michel De Cian, Barinjaka Rakotomiaramanana, Raluca Anca Muresan

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the ac ...

2012

Measurement of b hadron production fractions in 7 TeV pp collisions

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Michel De Cian, Barinjaka Rakotomiaramanana, Raluca Anca Muresan

Measurements of b hadron production ratios in proton-proton collisions at a center-of-mass energy of 7 TeV with an integrated luminosity of 3 pb(-1) are presented. We study the ratios of strange B meson to light B meson production f(s)/(f(u) + f(d)) and La ...

American Physical Society2012

Search for the rare decays B-s(0) -> mu(+)mu(-) and B-0 -> mu(+)mu(-)

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Barinjaka Rakotomiaramanana, Michel De Cian, Raluca Anca Muresan

A search for the decays B-s(0) -> mu(+)mu(-) and B-0 -> mu(+)mu(-) is performed with 0.37 fb(-1) of pp collisions at root s = 7 TeV collected by the LHCb experiment in 2011. The upper limits on the branching fractions are B(B-s(0) -> mu(+)mu(-)) < 1.6 x 10 ...

2012

Search for Lepton Number Violating Decays B+ -> pi(-)mu(+)mu(+) and B+ -> K-mu(+)mu(+)

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Michel De Cian, Barinjaka Rakotomiaramanana, Raluca Anca Muresan

A search is performed for the lepton number violating decay B+ -> h(-)mu(+)mu(+), where h(-) represents a K- or a pi(-), using an integrated luminosity of 36 pb(-1) of data collected with the LHCb detector. The decay is forbidden in the standard model but ...

2012

Measurement of charged particle multiplicities in pp collisions at root s=7 TeV in the forward region

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Barinjaka Rakotomiaramanana, Michel De Cian, Raluca Anca Muresan

Charged particle production in proton-proton collisions is studied with the LHCb detector at a centre-of-mass energy of root s = 7 TeV in different intervals of pseudorapidity eta. Charged particles are reconstructed close to the interaction region in the ...

2012

Measurement of the effective B-S(0) -> K+K- lifetime

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Michel De Cian, Barinjaka Rakotomiaramanana, Raluca Anca Muresan

A measurement of the effective B-S(0) -> K+K- lifetime is presented using approximately 37 pb(-1) of data collected by LHCb during 2010. This quantity can be used to put constraints on contributions from processes beyond the Standard Model in the B-S(0) me ...

2012

Measurement of the B-s(0)-(B)over-bar(s)(0) oscillation frequency Delta m(s) in B-s(0) -> D-s(-)(3)pi decays

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Michel De Cian, Barinjaka Rakotomiaramanana, Raluca Anca Muresan

The B-s(0)-(B) over bar (0)(s) oscillation frequency Delta m(s) is measured with 36 pb(-1) of data collected in pp collisions at = 7 TeV by the LHCb experiment at the Large Hadron Collider. A total of 1381 B-s(0) -> D-s(-) pi(+) and B-s(0) -> D-s(-) pi(+)p ...

2012

First observation of the decay B-s(0) -> K(0)(K)over-bar(0)

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Michel De Cian, Barinjaka Rakotomiaramanana, Raluca Anca Muresan

The first observation of the decay B-s(0) -> K*(0)(K) over bar*(0) is reported using 35 pb(-1) of data collected by LHCb in proton-proton collisions at a centre-of-mass energy of 7 TeV. A total of 49.8 +/- 7.5 B-s(0) -> (K+pi(-))(K-pi(+)) events are observ ...

2012

Observation of J/psi-pair production in pp collisions at root s=7 TeV

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Julien Rouvinet, Michel De Cian, Barinjaka Rakotomiaramanana, Raluca Anca Muresan

The production of J/psi pairs in proton-proton collisions at a centre-of-mass energy of 7 TeV has been observed using an integrated luminosity of 37.5 pb(-1) collected with the LHCb detector. The production cross-section for pairs with both J/psi in the ra ...

2012