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

Simulations of CMOS pixel sensors with a small collection electrode, improved for a faster charge collection and increased radiation tolerance

CMOS pixel sensors with a small collection electrode combine the advantages of a small sensor capacitance with the advantages of a fully monolithic design. The small sensor capacitance results in a large ratio of signal-to-noise and a low analogue power consumption, while the monolithic design reduces the material budget, cost and production effort. However, the low electric field in the pixel corners of such sensors results in an increased charge collection time, that makes a fully efficient operation after irradiation and a timing resolution in the order of nanoseconds challenging for pixel sizes larger than approximately forty micrometers. This paper presents the development of concepts of CMOS sensors with a small collection electrode to overcome these limitations, using three-dimensional Technology Computer Aided Design simulations. The studied design uses a 0.18 micrometer process implemented on a high-resistivity epitaxial layer.Comment: Proceedings of the PIXEL 2018 Worksho

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

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

The Silicon Ministrip Detector of the DELPHI Very Forward Tracker

The subject of this work is the design, test and construction of a new silicon tracking detector for the extreme forward region of the DELPHI experiment at LEP. I joined the Very Forward Tracker (VFT) Ministrip group in 1993, at a time when the upgrade of the DELPHI tracking system was proposed. My first task was to participate in the design of the ministrip detector for the VFT. This included the optimisation of the detector layout in simulations and the study of prototype detectors in the testbeam. In 1994 I became responsible for the tests and assembly' of the VFT ministrip detector at CERN. The main focus of my work was the study of the performance of a large variety of detectors in beam tests. This included the preparation of the test setup, the tests of different detectors and the analysis of the measurements. With these measurements it is possible to compare the advantages and disadvantages of various new layouts for large pitch silicon strip detectors. In particular the signal response and spatial resolution of the VFT ministrip detector was precisely measured and modelled. The results of this study form the central part of my thesis. During 1995, prior to the assembly of the VFT detector, my main task was the quality monitoring of the final VFT ministrip detectors in acceptance tests at CERN. The experience gained during these tests was subsequently used to optimise the control of the detector to assure reliable operation in DELPHI. In the following I will give a brief overview of the contents of this thesis: In chapter 1 an overview of the DELPHI detector and its components, in particular the silicon tracking detector, is presented. Chapter 2 is dedicated to the design of the DELPHI Very For- ward Tracker. The requirements for the VFT are given together with the considerations infiuencing the layout and capability of the detector. The chapter shows the complex environment in the extreme forward region of collider experiments. A new unconven- tional design with inclined detectors was necessary to optimise efficiency and acceptance area. The only way to cope with the tight space constraints in the forward region is to mount the readout electronics on top of the active detector surface. The advantages and technical problems of this solution are described. Chapter 3 presents the results of testbeam studies carried out on different large pitch strip detectors. The signal response and spatial resolution of well known and newly developed detectors was precisely measured. This study allows the comparison of many different layouts concerning their track reconstruction capability and intrinsic problems like insufficient charge measurement. The study provides useful information for the VFT ministrip layout and demonstrates the influence of layout parameters. It also provides necessary information for the design of similar detectors to be used in the future LHC (Large Hadron Collider) experiments. The tracking capability of the VFT ministrip detector is pre$ented in chapter 4. As the tracks in DELPHI will be inclined with respect to the detector surface, dedicated measurements at different track angles were carried out with the VFT ministrip detector. The measured signal response and spatial resolution could be modelled in a simulation, which proves excellent agreement with measurement data. Chapter 4 is concluded by an evaluation of the effects infiuencing the spatial resolution. In chapter 5 the production of the VFT ministrip detector is summarised. The chapter prescnts test results from the acceptance test of the full VFT ministrip detector prior to the installation in DELPHI. Extensive tests with the final configuration helped us to op- timise the operation parameters and insure reliable detector operation. Throughout the last three years I have been given the possibility to report on my work for this thesis. The considerations and results of the detector design are sumrnerisecl in Nucl.Phys.B(Proc.Supp.)44(1995)292-295, which I had the pleasure to present at the 4th Int. Conference on Aclvanced Technology and Particle Physics 1994. The predictions of the detector simulation for the final layout has been accomplished with testbeam meas- urements on VFT prototype detectors (NIM A349(1994)424-430, DELPHI internal note DELPHI 94-44 Track 78). I had also the pleasure to report the results of the testbeam analysis with different large pitch detectors to the CMS collaboration ( CMS collaboration meeting, Feb. 1996). Write-ups of the results presented in chapter 3 and 4 are currently in preparation and will be submitted for publication. I owe special thanks to Dr. M. Krammer, head of the serniconductor group of the lnstitute for High Energy Physics, for the motivating work in his group and the many hours of fruitful discussions. His attention, encouragement and knowledge was essential for this thesis. I would like to thank my thesis superviser, Prof. M. Regier, for his constant support and interest over many years. His advise and guidance was important for the analysis presentecl in this thesis. I want to express my gratefullness to Prof. W. Majerotto, director of the Institute for High Energy Physics, for financial support during this work. Furthermore I want to thank all my colleagues, in particular W. Adam, D. Rakoczy, N. Ncufelcl, V. Cindro, V. Rykalin and R. Turchetta. I also want to a.cknowlcclge the help of Prof. P. Weilhammer and Dr. W. Dulinski for their support during the test.bca.m rneasurements and the supply of many test detectors. Finally I want to thank my beloved girl-friend Bruna for all her patience and encour- agement throughout the years. I dedicate this thesis to Bruna

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

Störungen der Affektspiegelung

In der vorliegenden Diplomarbeit zum Thema „Störungen der Affektspiegelung – eine Indikation für Eltern-Kleinkind-Beratung/Therapie?“ findet eine Auseinandersetzung mit den von Peter Fonagy und seinen MitarbeiterInnen beschriebenen Störungen der Affektspiegelung in der frühen Mutter-Kind-Interaktion und verschiedenen Formen der Eltern-Kleinkind-Beratung/Therapie statt. Bereits in einer frühen Lebensphase können bei Säuglingen und Kleinkinder Störungen und Symptome auftreten, wie z.B. exzessives Schreien, Schlaf- und Gedeihstörungen, exzessives Trotzverhalten etc., die ihre Eltern dazu veranlassen, eine Eltern-Kleinkind-Beratung/Therapie in Anspruch zu nehmen. Im Bereich der Eltern-Kleinkind-Beratung/Therapie wird daher verstärkt nach Erklärungsmodellen gesucht, die diese bei Säuglingen und Kleinkindern auftretenden Symptome verständlich machen. In Hinblick auf ein mögliches Erklärungsmodell werden Überlegungen der Forschungsgruppe um Peter Fonagy zur Entwicklung der Mentalisierungsfähigkeit herangezogen und deren Störungsmodell der mütterlichen Affektspiegelung kritisch reflektiert. Anhand der zur Thematik bestehenden Fachliteratur wird erläutert und diskutiert, mit welchen „Instrumenten“ Störungen der Affektspiegelung im Rahmen der Eltern-Kleinkind-Beratung/Therapie diagnostizierbar sind und inwiefern Störungen der Affektspiegelung mit den Symptomen der Säuglinge und Kleinkinder in Zusammenhang stehen sowie welche Beratungs- und Therapieformen im Falle einer beeinträchtigten Affektspiegelung indiziert sind. Als Ergebnis wird festgehalten, dass in Fällen, in denen Störungen der Affektspiegelung diagnostiziert werden, spezielle Behandlungstechniken indiziert sind, die ihren Fokus auf die Förderung der elterlichen Mentalisierungsfähigkeit richten.This present thesis is concerned with the issue of ‚affect-mirroring disorders – an indication for parents-infant councelling/therapy?’. It debates disorders of affect-mirroring in early mother-child interaction, which have been described by Peter Fonagy and his associates. Furthermore, different forms of parents-infant councelling/therapy are discussed. Disorders and symptoms like for example excessive screaming, sleeping and developing disorders, excessive defiant behaviour etc. can already occur at an early stage of an infant’s life, which causes parents to make use parents-infant councelling/therapy. Therefore, in the field of parents-infant coucelling/therapy an intensified search for explanatory models, which can explain those symptoms occuring with infants, is taking place. With regard to a possible explanatory model the considerations of the research group around Peter Fonagy on the development of the Theory of Mind are consulted and the presented disorder model of maternal affect-mirroring is reflected on critically. On the basis of present specialist literature on this issue the question which ‚instruments’ can be used to diagnose disorders of affect-mirroring in the context of parents-infant coucelling/therapy is discussed and commented on. Other points are in how far affect-mirroring disorders can be related to the infants’ symptoms and which forms of coucelling and therapy are indicated in case of an impaired affect-mirroring. Finally, the conclusion is drawn that in cases in which disorders of affect-mirroring have been diagnosed special methods of treatment that focus on the promotion of the parental capacity for understanding mental states are indicated