Results from CHIPIX-FE0, a Small Scale Prototype of a New Generation Pixel Readout ASIC in 65nm CMOS for HL-LHC

CHIPIX65-FE0 is a readout ASIC in CMOS 65nm designed by the CHIPIX65 project for a pixel detector at the HL-LHC, consisting of a matrix of 64x64 pixels of dimension 50x50 μm2. It is fully functional, can work at low thresholds down to 250e− and satisfies all the specifications. Results confirm low-noise, fast performance of both the synchronous and asynchronous front-end in a complex digital chip. CHIPIX65-FE0 has been irradiated up to 600 Mrad and is only marginally affected on analog performance. Further irradiation to 1 Grad will be performed. Bump bonding to silicon sensors is now on going and detailed measurements will be presented. The HL-LHC accelerator will constitute a new frontier for particle physics after year 2024. One major experimental challenge resides in the inner tracking detectors, measuring particle position: here the dimension of the sensitive area (pixel) has to be scaled down with respect to LHC detectors. This paper describes the results obtained by CHIPIX65-FE0, a readout ASIC in CMOS 65nm designed by the CHIPIX65 project as small-scale demonstrator for a pixel detector at the HL-LHC. It consists of a matrix of 64x64 pixels of dimension 50x50 um2 pixels and contains several pieces that are included in RD53A, a large scale ASIC designed by the RD53 Collaboration: two out of three front-ends (a synchronous and an asynchronous architecture); several building blocks; a (4x4) pixel region digital architecture with central local buffer storage, complying with a 3 GHz/cm2 hit rate and a 1 MHz trigger rate maintaining a very high efficiency (above 99%). The chip is 100% functional, either running in triggered or trigger-less mode. All building-blocks (DAC, ADC, Band Gap, SER, sLVS-TX/RX) and very front ends are working as expected. Analog performance shows a remarkably low ENC of 90e-, a fast-rise time below 25ns and low-power consumption (about 4μA/pixel) in both synchronous and asynchronous front-ends; a very linear behavior of CSA and discriminator. No significant cross talk from digital electronics has been measured, achieving a low threshold of 250e-. Signal digitization is obtained with a 5b-Time over Threshold technique and is shown to be fairly linear, working well either at 80 MHz or with higher frequencies of 300 MHz obtained with a tunable local oscillator. Irradiation results up to 600 Mrad at low temperature (-20°C) show that the chip is still fully functional and analog performance is only marginally degraded. Further irradiation will be performed up to 1 Grad either at low or room temperature, to further understand the level of radiation hardness of CHIPIX65-FE0. We are now in the process of bump bonding CHIPIX65-FE0 to 3D and possibly planar silicon sensors during spring. Detailed results will be presented in the conference paper

Measurement of the Z/gamma* + b-jet cross section in pp collisions at 7 TeV

The production of b jets in association with a Z/gamma* boson is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV and recorded by the CMS detector. The inclusive cross section for Z/gamma* + b-jet production is measured in a sample corresponding to an integrated luminosity of 2.2 inverse femtobarns. The Z/gamma* + b-jet cross section with Z/gamma* to ll (where ll = ee or mu mu) for events with the invariant mass 60 < M(ll) < 120 GeV, at least one b jet at the hadron level with pT > 25 GeV and abs(eta) < 2.1, and a separation between the leptons and the jets of Delta R > 0.5 is found to be 5.84 +/- 0.08 (stat.) +/- 0.72 (syst.) +(0.25)/-(0.55) (theory) pb. The kinematic properties of the events are also studied and found to be in agreement with the predictions made by the MadGraph event generator with the parton shower and the hadronisation performed by PYTHIA.Comment: Submitted to the Journal of High Energy Physic

The CMS Silicon Strip Tracker: Status and Performance

The CMS Silicon Strip Tracker is the largest silicon detector ever built. The high precision measurement of track hit position, over a large radius range, determine the unprecedented performance of CMS tracking. The operational experience matured on this very complex detector up to the first half of 2011 and the current status are described here, including the powering system, cooling and the back-end electronics. The commissioning sequence to calibrate the detector is illustrated and results on the detector performance are presented

Characterization of planar and 3D Silicon pixel sensors for the high luminosity phase of the CMS experiment at LHC

The High Luminosity upgrade of the CERN LHC collider (HL-LHC) demands for a new, high-radiation tolerant solid-state pixel sensor capable of surviving fluencies up to a few $10^{16}~ \rm{n_{eq}/cm^2}$ at $\sim 3 \, \rm{cm}$ from the interaction point. To this extent the INFN ATLAS-CMS joint research activity, in collaboration with Fondazione Bruno Kessler (FBK), is aiming at the development of thin n-in-p type pixel sensors for the HL-LHC. The R\&D covers both planar and single-sided 3D columnar pixel devices made with the Si-Si Direct Wafer Bonding technique, which allows for the production of sensors with 100\,$\mu {\rm m}$ and 130\,$\mu {\rm m}$ active thickness for planar sensors, and 130\,$\mu {\rm m}$ for 3D sensors, the thinnest ones ever produced so far. Prototypes of hybrid modules, bump-bonded to the RD53A readout chip, have been tested on beam. First results on their performance before and after irradiation are presented. \footnote{Published in Proceedings of Science as PoS(EPS-HEP2019)117, DOI: 10.22323/1.364.0117}The High Luminosity upgrade of the CERN LHC collider (HL-LHC) demands for a new, high-radiation tolerant solid-state pixel sensor capable of surviving fluencies up to a few $10^{16}~ \rm{n_{eq}/cm^2}$ at $\sim 3 \, \rm{cm}$ from the interaction point. To this extent the INFN ATLAS-CMS joint research activity, in collaboration with Fondazione Bruno Kessler (FBK), is aiming at the development of thin n-in-p type pixel sensors for the HL-LHC. The R\&D; covers both planar and single-sided 3D columnar pixel devices made with the Si-Si Direct Wafer Bonding technique, which allows for the production of sensors with 100 $\mu {\rm m}$ and 130 $\mu {\rm m}$ active thickness for planar sensors, and 130 $\mu {\rm m}$ for 3D sensors, the thinnest ones ever produced so far. Prototypes of hybrid modules, bump-bonded to the RD53A readout chip, have been tested on beam.First results on their performance before and after irradiation are presented

Survey of neonatal respiratory care and surfactant administration in very preterm infants in the Italian neonatal network

Introduction: Variation of respiratory care is described between centers around the world.The Italian Neonatal Network (INN), as a national group of the Vermont-Oxford Network (VON) allows to perform a wide analysis of respiratory care in very low birth weight infants. Methods:We analyzed the dataset of infants enrolled in the INN in 2009 and 2010 and, for surfactant administration only, from 2006 to 2010 from 83 participating centers. All definitions are those of the (VON). A questionnaire analysis was also performed with a questionnaire on centers practices. Results: We report data for 8297 infants. Data on ventilator practices and outcomes are outlined. Variation for both practices and outcome is found. Trend in surfactant administration is also analyzed. Conclusions. The great variation across hospitals in all the surveyed techniques points to the possibility of implementing potentially better practices with the aim of reducing unwanted variation. These data also show the power of large neonatal networks in identifying areas for potential improvement. \ua9 Mattioli 1885

Survey of neonatal respiratory care and surfactant administration in very preterm infants in the Italian neonatal network

Introduction: Variation of respiratory care is described between centers around the world.The Italian Neonatal Network (INN), as a national group of the Vermont-Oxford Network (VON) allows to perform a wide analysis of respiratory care in very low birth weight infants. Methods:We analyzed the dataset of infants enrolled in the INN in 2009 and 2010 and, for surfactant administration only, from 2006 to 2010 from 83 participating centers. All definitions are those of the (VON). A questionnaire analysis was also performed with a questionnaire on centers practices. Results: We report data for 8297 infants. Data on ventilator practices and outcomes are outlined. Variation for both practices and outcome is found. Trend in surfactant administration is also analyzed. Conclusions. The great variation across hospitals in all the surveyed techniques points to the possibility of implementing potentially better practices with the aim of reducing unwanted variation. These data also show the power of large neonatal networks in identifying areas for potential improvement. © Mattioli 1885