Matches in SemOpenAlex for { <https://semopenalex.org/work/W1514980809> ?p ?o ?g. }
Showing items 1 to 90 of
90
with 100 items per page.
- W1514980809 abstract "The LHCb experiment is one of the four main experiments at the Large Hadron Collider (LHC) at CERN. The LHCb detector is a one-arm spectrometer dedicated to precise measurements of the CP-violation and studies or rare b-hadron decays. The centre of mass energy and luminosity (for a hadron collider) have both values never reached before. LHCb started data taking in November 2009. LHCb relies on excellent reconstruction and trigger efficiency, very good mass and proper time resolution, reliable particle identification systems to achieve the wanted precision on CP-violation parameters. These performances cannot be fulfilled without the detector to be calibrated. For instance, the Inner Tracker (IT) is readout by around a thousand chips, and the data are processed by 42 data acquisition cards, called TELL1. The Tracker Turicensis (TT) data are processed by 48 TELL1 boards. Each of these TELl1 boards has more than 18,000 parameters that need to be tuned in order to reduce the fake hits in the tracking systems. A high number of fake hits would result in poorer tracking performances. The first part of this thesis discuss the calibration of the IT and TT TELL1 boards. The first step was to find a way to extract the needed parameter values from data taken without beam. Once the parameters were gathered, a way to store them for future usage had to be found. The chosen solution was to use XML file, since XML files were already used for the detector geometry description and detector conditions. The XML file offered a convenient way to use the TELL1 parameters in the software framework, but those parameters were of course also required for data taking, i.e. they have to be uploaded to the TELL1 boards. A software library had to be developed in order to 'translate' the information contained in the XML file into a format handled by the control software. The second part discusses hit efficiency measurements in the IT. These measurements were shown to allow a monitoring of the detector status, as several hardware problems could be discovered by looking at the obtained efficiencies. Studies of the efficiency as a function of the clustering threshold allowed to improve background rejection in IT and TT by increasing one of the clustering thresholds. Finally, the last part covers the measurement of the B-meson lifetime in three decay channels: B+ → J/ψ(1S) (μ+ μ-) K+, B0 → J/ψ(1S) (μ+ μ-) K*0 (K+ π-), Bs0 → J/ψ(1S) (μ+ μ-) φ (K+ K-). These values are already quite well known for B± and B0, but their measurement represents a milestone in the measurement of the CP violating phase φs in the Bs0 → J/ψ (1S) φ decay. Lifetime ratios are also presented: τB± / τB0, τBs0 / τB0 and τB+ / τB-. The first two allow to probe the Heavy Quark Effective Theory (HQET), whilst the last one is a test of CPT symmetry, foundation of the Quantum Field Theory." @default.
- W1514980809 created "2016-06-24" @default.
- W1514980809 creator A5035893453 @default.
- W1514980809 date "2016-05-17" @default.
- W1514980809 modified "2023-09-24" @default.
- W1514980809 title "Measurements of B-meson lifetime ratios with the LHCb detector" @default.
- W1514980809 cites W1530385701 @default.
- W1514980809 cites W1551048750 @default.
- W1514980809 cites W1858769162 @default.
- W1514980809 cites W1969516334 @default.
- W1514980809 cites W1972788080 @default.
- W1514980809 cites W1985388980 @default.
- W1514980809 cites W2030151569 @default.
- W1514980809 cites W2070151728 @default.
- W1514980809 cites W2072831078 @default.
- W1514980809 cites W2078536640 @default.
- W1514980809 cites W2108415828 @default.
- W1514980809 cites W2109896109 @default.
- W1514980809 cites W2151578291 @default.
- W1514980809 cites W2188947131 @default.
- W1514980809 cites W2274653525 @default.
- W1514980809 cites W2275486211 @default.
- W1514980809 cites W2949268303 @default.
- W1514980809 cites W3009413113 @default.
- W1514980809 cites W38248666 @default.
- W1514980809 hasPublicationYear "2016" @default.
- W1514980809 type Work @default.
- W1514980809 sameAs 1514980809 @default.
- W1514980809 citedByCount "0" @default.
- W1514980809 crossrefType "book" @default.
- W1514980809 hasAuthorship W1514980809A5035893453 @default.
- W1514980809 hasConcept C109214941 @default.
- W1514980809 hasConcept C120665830 @default.
- W1514980809 hasConcept C121332964 @default.
- W1514980809 hasConcept C12287442 @default.
- W1514980809 hasConcept C152290109 @default.
- W1514980809 hasConcept C15744967 @default.
- W1514980809 hasConcept C165838908 @default.
- W1514980809 hasConcept C185544564 @default.
- W1514980809 hasConcept C19417346 @default.
- W1514980809 hasConcept C2775936607 @default.
- W1514980809 hasConcept C33390570 @default.
- W1514980809 hasConcept C41002478 @default.
- W1514980809 hasConcept C62520636 @default.
- W1514980809 hasConcept C87668248 @default.
- W1514980809 hasConcept C94915269 @default.
- W1514980809 hasConcept C98444146 @default.
- W1514980809 hasConceptScore W1514980809C109214941 @default.
- W1514980809 hasConceptScore W1514980809C120665830 @default.
- W1514980809 hasConceptScore W1514980809C121332964 @default.
- W1514980809 hasConceptScore W1514980809C12287442 @default.
- W1514980809 hasConceptScore W1514980809C152290109 @default.
- W1514980809 hasConceptScore W1514980809C15744967 @default.
- W1514980809 hasConceptScore W1514980809C165838908 @default.
- W1514980809 hasConceptScore W1514980809C185544564 @default.
- W1514980809 hasConceptScore W1514980809C19417346 @default.
- W1514980809 hasConceptScore W1514980809C2775936607 @default.
- W1514980809 hasConceptScore W1514980809C33390570 @default.
- W1514980809 hasConceptScore W1514980809C41002478 @default.
- W1514980809 hasConceptScore W1514980809C62520636 @default.
- W1514980809 hasConceptScore W1514980809C87668248 @default.
- W1514980809 hasConceptScore W1514980809C94915269 @default.
- W1514980809 hasConceptScore W1514980809C98444146 @default.
- W1514980809 hasLocation W15149808091 @default.
- W1514980809 hasOpenAccess W1514980809 @default.
- W1514980809 hasPrimaryLocation W15149808091 @default.
- W1514980809 hasRelatedWork W1482179602 @default.
- W1514980809 hasRelatedWork W1488798653 @default.
- W1514980809 hasRelatedWork W1494885852 @default.
- W1514980809 hasRelatedWork W1507298192 @default.
- W1514980809 hasRelatedWork W1533573173 @default.
- W1514980809 hasRelatedWork W1603283441 @default.
- W1514980809 hasRelatedWork W1613390274 @default.
- W1514980809 hasRelatedWork W1825477380 @default.
- W1514980809 hasRelatedWork W2104511354 @default.
- W1514980809 hasRelatedWork W2167981889 @default.
- W1514980809 hasRelatedWork W2169357054 @default.
- W1514980809 hasRelatedWork W2245226274 @default.
- W1514980809 hasRelatedWork W2279242600 @default.
- W1514980809 hasRelatedWork W2397128375 @default.
- W1514980809 hasRelatedWork W2569195707 @default.
- W1514980809 hasRelatedWork W2607171993 @default.
- W1514980809 hasRelatedWork W2965923083 @default.
- W1514980809 hasRelatedWork W597302994 @default.
- W1514980809 hasRelatedWork W70041049 @default.
- W1514980809 hasRelatedWork W2149074393 @default.
- W1514980809 isParatext "false" @default.
- W1514980809 isRetracted "false" @default.
- W1514980809 magId "1514980809" @default.
- W1514980809 workType "book" @default.