Performance of novel silicon n-in-p planar Pixel Sensors

The performance of novel n-in-p planar pixel detectors, designed for future upgrades of the ATLAS Pixel system is presented. The n-in-p silicon sensors technology is a promising candidate for the pixel upgrade thanks to its radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. The n-in-p modules presented here are composed of pixel sensors produced by CiS connected by bump-bonding to the ATLAS readout chip FE-I3. The characterization of these devices has been performed before and after irradiation up to a fluence of 5 x 10**15 1 MeV neq cm-2 . Charge collection measurements carried out with radioactive sources have proven the functioning of this technology up to these particle fluences. First results from beam test data with a 120 GeV/c pion beam at the CERN-SPS are also discussed, demonstrating a high tracking efficiency of (98.6 \pm 0.3)% and a high collected charge of about 10 ke for a device irradiated at the maximum fluence and biased at 1 kV.Comment: Preprint submitted to Nuclear Instruments and Methods A. 7 pages, 13 figure

Novel Silicon n-in-p Pixel Sensors for the future ATLAS Upgrades

In view of the LHC upgrade phases towards HL-LHC the ATLAS experiment plans to upgrade the Inner Detector with an all silicon system. The n-in-p silicon technology is a promising candidate for the pixel upgrade thanks to its radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. We present the characterization and performance of novel n-in-p planar pixel sensors produced by CiS (Germany) connected by bump bonding to the ATLAS readout chip FE-I3. These results are obtained before and after irradiation up to a fluence of 10^16 1-MeV n_eq/cm^2, and prove the operability of this kind of sensors in the harsh radiation environment foreseen for the pixel system at HL-LHC. We also present an overview of the new pixel production, which is on-going at CiS for sensors compatible with the new ATLAS readout chip FE-I4.Comment: Preprint submitted to NIM-A Proceedings (Elba 2012

Diamond pixel detector for beam profile monitoring in COMET experiment at J-PARC

We present the design and initial prototype results of a pixellized proton beam profile monitor for the COMET experiment at J-PARC. The goal of COMET is to look for charged lepton flavor violation by direct muon to electron conversion at a sensitivity of $0^{-19}$. An 8 GeV proton beam pulsed at 100 ns with $10^{10}$ protons/s will be used to create muons through pion production and decay. In the final experiment, the proton flux will be raised to $10^{14}$ protons/sec to increase the sensitivity. These requirements of harsh radiation tolerance and fast readout make diamond a good choice for constructing a beam profile monitor in COMET. We present first results of the characterization of single crystal diamond (scCVD) sourced from a new company, 2a systems Singapore. Our measurements indicate excellent charge collection efficiency and high carrier mobility down to cryogenic temperatures.Comment: Pixel 2014 Workshop proceedings in JINS

The ATLAS Insertable B-Layer Detector (IBL)

The ATLAS Collaboration has decided the construction of a new pixel detector to install in the 2014 shutdown of the LHC machine (SLHC Phase I). The new detector will be inserted between the existing pixel detector (that will remain unchanged) and a new, smaller radius, beampipe. This new detector, at a radius of 3.7 cm, will require the development of several new technologies to cope with increase of radiation or pixel occupancy and also to improve the physics performance which will be achieved by reduction of the pixel size and of the material budget. An overview of the project with highlights of the going on developments will be given

Characterization of charge collection in CdTe and CZT using the transient current technique

The charge collection properties in different particle sensor materials with respect to the shape of the generated signals, the electric field within the detector, the charge carrier mobility and the carrier lifetime are studied with the transient current technique (TCT). Using the well-known properties of Si as a reference, the focus is laid on Cadmium-Telluride (CdTe) and Cadmium-Zinc-Telluride (CZT), which are currently considered as promising candidates for the efficient detection of X-rays. All measurements are based on a transient-current technique (TCT) setup, which allows the recording of current pulses generated by an 241Am alpha-source. These signals will be interpreted with respect to the build-up of space-charges inside the detector material and the subsequent deformation of the electric field. Additionally the influence of different electrode materials (i.e. ohmic or Schottky contacts) on the current pulse shapes will be treated in the case of CdTe. Finally, the effects of polarization, i.e. the time-dependent degradation of the detector signals due to the accumulation of fixed charges within the sensor, are presented.Comment: 20 pages, 17 figure

Performance of n-in-p pixel detectors irradiated at fluences up to 5x10**15 neq/cm**2 for the future ATLAS upgrades

We present the results of the characterization of novel n-in-p planar pixel detectors, designed for the future upgrades of the ATLAS pixel system. N-in-p silicon devices are a promising candidate to replace the n-in-n sensors thanks to their radiation hardness and cost effectiveness, that allow for enlarging the area instrumented with pixel detectors. The n-in-p modules presented here are composed of pixel sensors produced by CiS connected by bump-bonding to the ATLAS readout chip FE-I3. The characterization of these devices has been performed with the ATLAS pixel read-out systems, TurboDAQ and USBPIX, before and after irradiation with 25 MeV protons and neutrons up to a fluence of 5x10**15 neq /cm2. The charge collection measurements carried out with radioactive sources have proven the feasibility of employing this kind of detectors up to these particle fluences. The collected charge has been measured to be for any fluence in excess of twice the value of the FE-I3 threshold, tuned to 3200 e. The first results from beam test data with 120 GeV pions at the CERN-SPS are also presented, demonstrating a high tracking efficiency before irradiation and a high collected charge for a device irradiated at 10**15 neq /cm2. This work has been performed within the framework of the RD50 Collaboration.Comment: Proceedings of the Conference "Technology and Instrumentation in Particle Physics 2011

High-Resolution Energy and Intensity Measurements with CVD Diamond at REX-ISOLDE

A novel beam instrumentation device for the HIE-REX (High In-tensity and Energy REX) upgrade has been developed and tested at the On-Line Isotope Mass Separator ISOLDE, located at the European Laboratory for Particle Physics (CERN). This device is based on CVD diamond detector technology and is used for measuring the beam intensity, particle counting and measuring the energy spectrum of the beam. An energy resolution of 0.6% was measured at a carbon ion energy of 22.8 MeV. This corresponds to an energy spread of ± 140 keV

Silicon Pad Detectors for the PHOBOS Experiment at RHIC

The PHOBOS experiment is well positioned to obtain crucial information about relativistic heavy ion collisions at RHIC, combining a multiplicity counter with a multi-particle spectrometer. The multiplicity arrays will measure the charged particle multiplicity over the full solid angle. The spectrometer will be able to identify particles at mid-rapidity. The experiment is constructed almost exclusively of silicon pad detectors. Detectors of nine different types are configured in the multiplicity and vertex detector (22,000 channels) and two multi-particle spectrometers (120,000 channels). The overall layout of the experiment, testing of the silicon sensors and the performance of the detectors during the engineering run at RHIC in 1999 are discussed.Comment: 7 pages, 7 figures, 1 table, Late

Centrality Dependence of Charged Particle Multiplicity at Mid-Rapidity in Au+Au Collisions at sqrt(s_NN) = 130 GeV

We present a measurement of the pseudorapidity density of primary charged particles near mid-rapidity in Au+Au collisions at sqrt(s_NN) = 130 GeV as a function of the number of participating nucleons. These results are compared to models in an attempt to discriminate between competing scenarios of particle production in heavy ion collisions.Comment: 5 pages, 4 figures, revtex (submitted to Phys. Rev. Letters