L. Castillo García
A5040816096- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Black Holes and Theoretical Physics
- Computational Physics and Python Applications
- Radiation Detection and Scintillator Technologies
- Cosmology and Gravitation Theories
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- Distributed and Parallel Computing Systems
- Superconducting Materials and Applications
- Radiation Effects in Electronics
- Stochastic processes and statistical mechanics
- Astrophysics and Cosmic Phenomena
- Radiation Therapy and Dosimetry
- Advanced NMR Techniques and Applications
- Advanced Optical Sensing Technologies
- Nuclear physics research studies
- Digital Radiography and Breast Imaging
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
Institute for High Energy Physics
2020-2025
Barcelona Institute for Science and Technology
2024-2025
Institute of Science and Technology
2024-2025
University of California, Santa Cruz
2023-2024
Istanbul University
2023-2024
SR Research (Canada)
2024
Federación Española de Enfermedades Raras
2024
Atlas Scientific (United States)
2024
European Organization for Nuclear Research
2013-2023
The University of Adelaide
2022-2023
We present a measurement of form-factor-independent angular observables in the decay ${B}^{0}\ensuremath{\rightarrow}{K}^{*}(892{)}^{0}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$. The analysis is based on data sample corresponding to an integrated luminosity $1.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$, collected by LHCb experiment $pp$ collisions at center-of-mass energy 7 TeV. Four are measured six bins dimuon invariant mass squared ${q}^{2}$ range...
A search for the rare decays ${B}_{s}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ and ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ is performed at LHCb experiment. The data analyzed correspond to an integrated luminosity of $1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ $pp$ collisions a center-of-mass energy 7 TeV $2\text{ 8 TeV. An excess signal candidates with respect background expectation seen...
An angular analysis of the decay J/ψ→μ+μ- is performed to measure polarization prompt J/ψ mesons produced in pp collisions at [Formula: see text]. The dataset corresponds an integrated luminosity 0.37 fb-1 collected with LHCb detector. measurement presented as a function transverse momentum, pT, and rapidity, y, meson, kinematic region 2<pT<15 GeV/c 2.0<y<4.5.
Using pp collision data corresponding to an integrated luminosity of 1.0 fb(-1) and collected by LHCb in 2011 at a center-of-mass energy 7 TeV, we report the measurement direct CP violation B(s)(0)→K(-)π(+) decays, A(CP)(B(s)(0)→K(-)π(+)=0.27±0.04 (stat)±0.01 (syst), with significance exceeding 5 standard deviations. This is first observation decays B(s)(0) mesons. Furthermore, provide improved determination B(0)→K(+)π(-) A(CP)(B(0)→K(+)π(-)=-0.080±0.007 (stat)±0.003 which most precise this...
The angular distribution and differential branching fraction of the decay $B^{0} \to K^{*0} \mu^{+}\mu^{-}$ are studied using a data sample, collected by LHCb experiment in $pp$ collisions at $\sqrt{s}=7\,{\rm TeV}$, corresponding to an integrated luminosity $1.0\,{\rm fb}^{-1}$. Several observables measured bins dimuon invariant mass squared, $q^{2}$. A first measurement zero-crossing point forward-backward asymmetry system is also presented. be $q_{0}^{2} = 4.9 \pm 0.9 \,{\rm...
A bstract The differential branching fraction of the rare decay Λ b 0 → Λμ + μ − is measured as a function q 2 , square dimuon invariant mass. analysis performed using proton-proton collision data, corresponding to an integrated luminosity 3 . fb −1 collected by LHCb experiment. Evidence signal observed in region below J/ψ Integrating over 15 < 20 GeV /c 4 $$ \mathrm{d}\mathrm{\mathcal{B}}\left({\varLambda}_b^0\to \varLambda {\mu}^{+}{\mu}^{-}\right)/d{q}^2=\left({1.18}_{-0.08}^{+0.09}\pm...
The production of J/ψ mesons with rapidity 1.5 < y 4.0 or −5.0 −2.5 and transverse momentum p T 14 GeV/c is studied the LHCb detector in proton-lead collisions at a nucleon-nucleon centre-of-mass energy $ \sqrt{{{s_{NN }}}} = 5TeV. are reconstructed using dimuon decay mode. analysis based on data sample corresponding to an integrated luminosity about 1.6 nb−1. For first time nuclear modification factor forward-backward ratio determined separately for prompt from b-hadron decays. Clear...
The charmless decays $B^{\pm}\to K^{\pm}\pi^+\pi^-$ and K^{\pm}K^+K^-$ are reconstructed using data, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected by LHCb in 2011. inclusive charge asymmetries these modes measured as $A_{C\!P}(B^{\pm}\to K^{\pm}\pi^+\pi^-) = 0.032 \pm 0.008 \stat 0.004 \syst 0.007 (J\psi K^{\pm})$ K^{\pm}K^+K^-) -0.043 0.009 0.003 K^{\pm})$, where the third uncertainty is due $C\!P$ asymmetry J\psi K^{\pm}$ reference mode. significance K^{\pm}K^+K^-)$...
The charmless decays ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ and ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ are reconstructed in a data set of $pp$ collisions with an integrated luminosity $1.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ center-of-mass energy 7 TeV,...
The production of J/psi and Upsilon mesons in pp collisions at sqrt(s) = 8 TeV is studied with the LHCb detector. are reconstructed mu+mu- decay mode signal yields determined a fit to invariant mass distributions. analysis performed rapidity range 2.0<y<4.5 transverse momentum 0<p_T<14(15) GeV/c J/psi(Upsilon) mesons. cross-sections fraction from b-hadron decays measured as function meson p_T y.
A bstract search for the doubly charmed baryon $ \Xi_{cc}^{+} in decay mode \Xi_{cc}^{+}\to \Lambda_c^{+}{K^{-}}{\pi^{+}} is performed with a data sample, corresponding to an integrated luminosity of 0.65 fb −1 , pp collisions recorded at centre-of-mass energy 7 TeV. No significant signal found mass range 3300-3800 MeV /c 2 . Upper limits 95% confidence level on ratio production cross-section times branching fraction that \Lambda_c^{+} R are given as function and lifetime. The largest upper...
A bstract The decay $ B_c^{+}\to {J \left/ {{\psi {K^{+}}}} \right.} is observed for the first time using a data sample, corresponding to an integrated luminosity of 1.0 fb −1 , collected by LHCb experiment in pp collisions at centre-of-mass energy 7 TeV. yield 46 ± 12 events reported, with significance 5.0 standard deviations. ratio branching fraction that {\pi^{+}}}} measured be 0.069 0.019 0.005, where uncertainty statistical and second systematic.
Measurements of charm mixing parameters from the decay-time-dependent ratio ${D}^{0}\ensuremath{\rightarrow}{K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ to ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}$ rates and charge-conjugate are reported. The analysis uses data, corresponding $3\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ integrated luminosity, proton-proton collisions at 7 8 TeV center-of-mass energies recorded by LHCb experiment. In limit charge-parity...
A bstract The production cross-sections of B mesons are measured in pp collisions at a centre-of-mass energy 7 TeV, using data collected with the LHCb detector corresponding to integrated luminosity 0.36 fb −1 . + , 0 and $ B_s^0 reconstructed exclusive decays → J / ψK *0 B_s^0\to {J \left/ {{\psi \phi }} \right.} ψ μ − K π ϕ differential as functions meson transverse momentum p T rapidity y range < 40 GeV /c 2 4 5. same ranges, including charge-conjugate states, be...
A broad peaking structure is observed in the dimuon spectrum of $B^+ \to K^+ \mu^+\mu^-$ decays kinematic region where kaon has a low recoil against system. The consistent with interference between decay and resonance statistical significance exceeding six standard deviations. mean width are measured to be $4191^{+9}_{-8}\mathrm{\,Me\kern -0.1em V/}c^2$ $65^{+22}_{-16}\mathrm{\,Me\kern V/}c^2$, respectively, uncertainties include systematic contributions. These measurements compatible...
The ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}^{+}{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}}$ decay is observed in a data sample corresponding to $3.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of $pp$ collision recorded by the LHCb experiment during 2011 and 2012. Its branching fraction measured be...
A combination of three LHCb measurements the CKM angle gamma is presented. The decays B->DK and B->Dpi are used, where D denotes an admixture D0 D0-bar mesons, decaying into K+K-, pi+pi-, K+-pi-+, K+-pi-+pi+-pi-+, KSpi+pi-, or KSK+K- final states. All use a dataset corresponding to 1.0 fb-1 integrated luminosity. Combining results from alone best-fit value = 72.0 deg found, confidence intervals set in [56.4,86.7] at 68% CL, [42.6,99.6] 95% CL. found alone, 18.9 deg, [7.4,99.2] [167.9,176.4]...
The differential branching fraction of the rare decay $\Lambda^{0}_{b} \rightarrow \Lambda \mu^+\mu^-$ is measured as a function $q^{2}$, square dimuon invariant mass. analysis performed using proton-proton collision data, corresponding to an integrated luminosity $3.0 \mbox{ fb}^{-1}$, collected by LHCb experiment. Evidence signal observed in $q^2$ region below $J/\psi$ Integrating over $15 < q^{2} 20 GeV}^2/c^4$ $d\mathcal{B}(\Lambda^{0}_{b} \mu^+\mu^-)/dq^2 = (1.18 ^{+ 0.09} _{-0.08} \pm...
A search for the rare decay $D^0 \to μ^+ μ^-$is performed using a data sample, corresponding to an integrated luminosity of 0.9 fb$^{-1}$, $pp$ collisions collected at centre-of-mass energy 7 TeV by LHCb experiment. The observed number events is consistent with background expectations and corresponds upper limit \mbox{${\cal B}(D^0 μ^-) < 6.2(7.6) \times 10^{-9}$} \mbox{90%} \mbox{(95%)} confidence level. This result represents improvement more than factor twenty respect previous measurements.
Top quark production in the forward region proton-proton collisions is observed for first time. The $W+b$ final state with $W\ensuremath{\rightarrow}\ensuremath{\mu}\ensuremath{\nu}$ reconstructed using muons a transverse momentum, ${p}_{T}$, larger than 25 GeV pseudorapidity range $2.0<\ensuremath{\eta}<4.5$. $b$ jets are required to have $50<{p}_{T}<100\text{ }\text{ }\mathrm{GeV}$ and $2.2<\ensuremath{\eta}<4.2$, while component of sum muon $b$-jet momenta must satisfy ${p}_{T}>20\text{...
Searches for the lepton flavour violating decay $\tau^-\rightarrow \mu^-\mu^+\mu^-$ and baryon number decays \bar{p}\mu^+\mu^-$ p\mu^-\mu^-$ have been carried out using proton-proton collision data, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, taken by LHCb experiment at $\sqrt{s} = 7$ TeV. No evidence has found any signal, limits set 90% confidence level on branching fractions: $\cal B(\tau^-\rightarrow \mu^-\mu^+\mu^-) < 8.0 \times 10^{-8}$, \bar{p}\mu^+\mu^-) 3.3 10^{-7}$...
The CP-violating asymmetry asls is studied using semileptonic decays of Bs0 and B¯s0 mesons produced in pp collisions at a centre-of-mass energy 7 TeV the LHC, exploiting data sample corresponding to an integrated luminosity 1.0fb−1. reconstructed final states are Ds±μ∓, with Ds± particle decaying ϕπ± mode. Ds±μ∓ yields summed over initial states, respect decay time. Data-driven methods used measure efficiency ratios. We obtain asls=(−0.06±0.50±0.36)%, where first uncertainty statistical...
The ratio of the ${\ensuremath{\Lambda}}_{b}^{0}$ baryon lifetime to that ${\overline{B}}^{0}$ meson is measured using $1.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ integrated luminosity in 7 TeV center-of-mass energy $pp$ collisions at LHC. observed for first time decay mode ${\ensuremath{\Lambda}}_{b}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}p{K}^{\ensuremath{-}}$, while used well known...