First experience and results with the LHCb Silicon Tracker Fave, V.; Bay, A.; Blanc, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1
Journal Article
Recenzirano
The LHCb experiment is designed to perform high-precision measurements of CP violation and rare decays of b hadrons. The construction and installation of the Silicon Tracker (ST) was completed by the ...summer of 2008. Here, we report on first results obtained using the data taken during injection tests (‘TED’ run) in August and September 2008.
LHCb Silicon Tracker DAQ and ECS Online Systems Esperante, Daniel; Rodriguez, P; Buchler, A ...
IEEE transactions on nuclear science,
2010-April, 2010-04-00, 20100401, Letnik:
57, Številka:
2
Journal Article
Recenzirano
The LHCb experiment at CERN is designed to perform precision measurements of b quark decays. The Silicon Tracker plays a crucial role in reconstructing particle trajectories and consists of two ...silicon micro-strip detectors, the Tracker Turicensis and the Inner Tracker. The radiation environment and the magnetic field represent new challenges for the implementation of the Experiment Control System (ECS) and the data acquisition (DAQ). The DAQ has to deal with ~272 000 analog read-out channels and real-time DAQ at a rate of ~ 1.1 MHz with data processing at the Trigger Electronics and L1 (TELL1) board level. The TELL1 real-time algorithms for clustering thresholds and other computations run on dedicated FPGAs. After data processing the total throughput amounts to about 6.4 GB from an input data rate of ~ 337 GB per second. The ECS is based on the hierarchical finite state machine paradigm and allows distributed control access and multi-platform use. The ECS is able to control and monitor the detector hardware infrastructure (power supplies, DAQ electronics ...) as well as monitor the environmental parameters. It can also take automated actions on warnings or alarms. Finally a completely independent, hardware based safety system ensures the detector safe operation.
First operational experience from the LHCb Silicon Tracker Gallas, A.; Bay, A.; Blanc, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2011, Letnik:
636, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The LHCb Silicon Tracker is a silicon micro-strip detector covering a sensitive area of 12
m
2 with a total of 272k readout channels. The installation of the detector is complete and commissioning is ...making excellent progress. The detector has recorded first beam-induced events during LHC synchronization tests in August 2008 and in June 2009. These events have allowed the performance to be studied, and adjustments to the operational parameters to be made. In this contribution, we will draw first lessons from the in situ commissioning of the Silicon Tracker, and present results from the reconstruction of data collected during the LHC synchronization tests.
Installation and operation of the LHCb Silicon Tracker detector Esperante, D.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2010, Letnik:
623, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The LHCb experiment is designed to perform high-precision measurements of CP violation and rare decays of B hadrons. The construction and installation of the Silicon Tracker (ST) was completed by ...early summer 2008. The Silicon Tracker covers a sensitive area of about 12m2 using silicon micro-strip technology and must withstand a radiation dose of 5×10131MeVn/cm2 equivalent after 10 years of operation. In these proceedings the preparation of the detectors for the first LHC beams is reported. Selected results from the detector commissioning in LHCb are shown, including the first beam-related events accumulated during the LHC injection and synchronization tests in September 2008. Lessons are drawn from the experience gathered during the installation and commissioning.
We give here a short review of the LHCb Silicon Tracker, the main points of the module production and quality control, followed by the commissioning of the detector. Problems that were found during ...production or commissioning are described and the first performance assessment of the installed detector with “beam data” is given.
The Large Hadron Collider beauty (LHCb) experiment at CERN (Conseil Européen pour la Recherche Nucléaire) is designed to perform precision measurements of b quark decays. The LHCb Silicon Tracker ...consists of two sub-detectors, the Tracker Turicensis and the Inner Tracker, which are built from silicon micro-strip technology. First performance results of both detectors using data from Large Hadron Collider synchronization tests are presented.
The LHCb experiment at the Large Hadron Collider (LHC) at CERN in Geneva (Switzerland) is designed to perform precision measurements of b quark decays. The Silicon Tracker (ST) plays a crucial role ...in reconstructing particle trajectories and consists of two silicon micro-strip detectors, the Tracker Turicensis upstream of the LHCb magnet and the Inner Tracker downstream. The radiation environment and the magnetic field represent new challenges for the implementation of a Detector Control System (DCS) and the data acquisition (DAQ).The DAQ has to deal with ~272 K analog read-out channels, 2 K read-out chips and real time DAQ at a rate of 1.1 MHz with data processing at TELL1 level. The TELL1 real time algorithms for clustering thresholds and other computations run on dedicated FPGAs that implement 13 K configurable parameters per board, in total 1.17 M parameters for the ST. After data processing the total throughput amounts to about 6.4 GB from an input data rate of ~337 GB per second. A finite state machine based hierarchical control system is the fundamental of the DCS and allows distributed control access and multi-platform use. The implementation of the DCS system for two sub-detectors requires a design which can be used for TT and IT which have a different hardware mapping. With the DCS an operator is able to control the power supplies, to program the read-out chips and to monitor online the state of all the hardware in the read-out chain. It features as well a monitoring of temperature and humidity readings and can take automated actions on warnings or alarms. To guarantee safe operation a completely independent, hardware-based system is used for the 'vital' alarms to ensure redundancy.
Fc-mediated antibody effector functions, such as antibody-dependent cellular cytotoxicity (ADCC), can contribute to the containment HIV-1 replication but whether such activities are sufficient for ...protection is unclear. We previously identified an antibody to the variable 2 (V2) apex of the HIV-1 Env trimer (PGT145) that potently directs the lysis of SIV-infected cells by NK cells but poorly neutralizes SIV infectivity. To determine if ADCC is sufficient for protection, separate groups of six rhesus macaques were treated with PGT145 or a control antibody (DEN3) by intravenous infusion followed five days later by intrarectal challenge with SIVmac239. Despite high concentrations of PGT145 and potent ADCC activity in plasma on the day of challenge, all animals became infected and viral loads did not differ between the PGT145- and DEN3-treated animals. To determine if PGT145 can protect against a neutralization-sensitive virus, two additional groups of six macaques were treated with PGT145 and DEN3 and challenged with an SIVmac239 variant with a single amino acid change in Env (K180S) that increases PGT145 binding and renders the virus susceptible to neutralization by this antibody. Although there was no difference in virus acquisition, peak and chronic phase viral loads were significantly lower and time to peak viremia was significantly delayed in the PGT145-treated animals compared to the DEN3-treated control animals. Env changes were also selected in the PGT145-treated animals that confer resistance to both neutralization and ADCC. These results show that ADCC is not sufficient for protection by this V2-specific antibody. However, protection may be achieved by increasing the affinity of antibody binding to Env above the threshold required for neutralization.
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