Abstract
This work presents the first measurements performed on the Timespot1 ASIC. As the second prototype developed for the TimeSPOT project, the ASIC features a 32 × 32 channels hybrid-pixel ...matrix. Targeted to space-time tracking applications in High Energy Physics experiments, the system aims to achieve a time resolution of 30 ps or better at a maximum event rate of 3 MHz/channel with a data driven interface. Power consumption can be programmed to range between 1.2 W/cm
2
and 2.6 W/cm
2
. The presented results include a description of the ASIC operation and a first characterization of its performance in terms of time resolution.
Abstract
We present first results obtained with a prototype 4D-tracking demonstrator, using sensors and electronics developed within the TimeSPOT project, and tested on a positive charged pion beam ...at CERN SPS. The setup consists of five small tracking layers in a row, having area of about 3 mm
2
each, three of which equipped with 3D-trench silicon sensors and two with 3D-column diamond sensors. The five layers are then read-out by a KC705 Xilinx board on a PC. We describe the demonstrator structure and operation and illustrate preliminary results on its tracking capabilities.
Digitally-controlled delay lines (DCDLs) play a key role in timing distribution for trigger and data acquisition systems (TDAQ) of high energy Physics (HEP), where it is often necessary to add an ...open-loop fine-grained programmable phase delay to distributed clocks and/or data lines. In this work, we present the performance of DCDLs implemented according to an all-digital novel architecture. The architecture is completely technology-independent, it is described by means of a hardware description language and it can be placed and routed with automatic tools. Our solution is aimed at being used as a synthesizable block in FPGAs, as a proof-of-concept we implemented a prototype in a Xilinx Kintex-7 FPGA. We discuss the measured performance of the implemented delay line in terms of delay range, resolution and linearity. The logic utilization of the delay lines is also presented in the view of a scalable implementation.
The performance of the muon identification in LHCb is extracted from data using muons and hadrons produced in J/psi arrow right mu super(+) mu super(-) , Lambda super(0) arrow right ppi super(-) and ...D* super(+) arrow right pi super(+)D super(0)(K super(-)pi super(+)) decays. The muon identification procedure is based on the pattern of hits in the muon chambers. A momentum dependent binary requirement is used to reduce the probability of hadrons to be misidentified as muons to the level of 1%, keeping the muon efficiency in the range of 95-98%. As further refinement, a likelihood is built for the muon and non-muon hypotheses. Adding a requirement on this likelihood that provides a total muon efficiency at the level of 93%, the hadron misidentification probabilities are below 0.6%.
The mixed-signal PRIMA-chip has been developed for sensitive-position silicon detector in proton imaging application. The chip is based upon the binary readout architecture which, providing fully ...parallel signal processing, is a good solution for high intensity radiation application. It includes 32-front-end channels with a charge preamplifier, a shaper and a comparator. In order to adjust the comparator thresholds, each channel contains a 8-bit DAC, programmed using an I2C like interface. The PRIMA-chip has been fabricated using the AMS 0.35 mum standard CMOS process and its performances have been tested coupling it to the detectors used in the tracker assembled for the pCT (proton Computed Tomography) apparatus.
We present a custom integrated circuit, named DIALOG (DIagnostic, time Adjustment and LOGics), which is a fundamental building block in the front-end architecture of the LHCb Muon detector. DIALOG is ...realized in IBM 0.25 mum technology, using radiation-hardening layout techniques. DIALOG integrates important tools for detector time alignment procedures and time alignment monitoring on the front-end system. In particular, it integrates 16 programmable delays, which can be regulated in steps of 1 ns. Other features, necessary for the Muon trigger operation and for a safe front-end monitoring are integrated into DIALOG. It generates the information, that will be used by the trigger, as a combination of its 16 inputs from the Amplifier-Shaper-Discriminator (ASD) chips, it generates the thresholds of the ASD, it monitors the rate of all its input channels. We describe the circuit architecture, its internal blocks and its main modes of operation. Measurements performed on final prototypes are also reported
A narrow pentaquark state, Pc(4312)+, decaying to J/ψp, is discovered with a statistical significance of 7.3σ in a data sample of Λb0→J/ψpK− decays, which is an order of magnitude larger than that ...previously analyzed by the LHCb Collaboration. The Pc(4450)+ pentaquark structure formerly reported by LHCb is confirmed and observed to consist of two narrow overlapping peaks, Pc(4440)+ and Pc(4457)+, where the statistical significance of this two-peak interpretation is 5.4σ. The proximity of the Σc+D¯0 and Σc+D¯*0 thresholds to the observed narrow peaks suggests that they play an important role in the dynamics of these states.
Study of the doubly charmed tetraquark Tcc Abdelmotteleb, A. S. W; Ajaltouni, Z; Andreianov, A ...
Nature communications,
12/2022, Letnik:
13, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Quantum chromodynamics, the theory of the strong force, describes interactions of coloured quarks and gluons and the formation of hadronic matter. Conventional hadronic matter consists of baryons and ...mesons made of three quarks and quark-antiquark pairs, respectively. Particles with an alternative quark content are known as exotic states. Here a study is reported of an exotic narrow state in the D0D0π+ mass spectrum just below the D*+D0 mass threshold produced in proton-proton collisions collected with the LHCb detector at the Large Hadron Collider. The state is consistent with the ground isoscalar Tcc+ tetraquark with a quark content of ccu¯d¯ and spin-parity quantum numbers JP = 1+. Study of the DD mass spectra disfavours interpretation of the resonance as the isovector state. The decay structure via intermediate off-shell D*+ mesons is consistent with the observed D0π+ mass distribution. To analyse the mass of the resonance and its coupling to the D*D system, a dedicated model is developed under the assumption of an isoscalar axial-vector Tcc+ state decaying to the D*D channel. Using this model, resonance parameters including the pole position, scattering length, effective range and compositeness are determined to reveal important information about the nature of the Tcc+ state. In addition, an unexpected dependence of the production rate on track multiplicity is observed.The existence and properties of tetraquark states with two heavy quarks and two light antiquarks have been widely debated. Here, the authors use a unitarized model to study the properties of an exotic narrow state compatible with a doubly charmed tetraquark.
PDF
