Investigation of Various Shaping Methods for the Development of a Fully-Monolithic CMOS Constant-Fraction Discriminator

In this work the design of a constant-fraction discriminator (CFD) fabricated in the Orbit Semiconductor l.2-Jl n-well CMOS process is presented. This timing pick-off circuit is designed for use in the readout electronics of the Lead-Scintillator subsystem of the Pioneering High Eenergy Nuclear Ion eXperiment (PHENIX) Electromagnetic Calorimeter at the Relativistic Heavy Ion Collider (RHIC). The design was driven by stringent requirements including low power consumption, small area, arrayable, low cost and a fully integratable shaping network. Various integratable CFD shaping methods are investigated, and the candidate methods chosen for fabrication were the distributed R-C delay-line shaping, lumped-element R-C shaping and Nowlin method shaping. An additional channel of ideal delay-line shaping, utilizing coaxial cable to generate delay, was fabricated and used for a reference in comparing methods. These shaping methods are compared on the basis of die area, time walk performance and timing jitter performance as implemented using the CMOS CFD presented. Each shaping method investigated required no power from the dc supply. Die area for the distributed R-C delay-line, lumped-element R-C, Nowlin method and ideal delay-line (fraction circuit only) were 172 Jl X 70 Jl, 160 Jl X 65 Jl, 179 Jl X 53 Jl and 67 Jl X65Jl,respectively. Timewalkovera100:1dynamicrange(-2Vpeakto-20mVpeak) for these shaping methods in turn was found to be ± 175 ps, ± 150ps , ± 150 ps and ± 185 ps, respectively. Timing jitter performance with a minimum input signal (-20 mVpeak) in rms units for the four methods in turn were 65 ps, 85 ps, 100 ps and 65 ps. The average power dissipated per CFD channel was found to be approximately 12 mW

Research Proposal for an Experiment to Search for the Decay {\mu} -> eee

We propose an experiment (Mu3e) to search for the lepton flavour violating decay mu+ -> e+e-e+. We aim for an ultimate sensitivity of one in 10^16 mu-decays, four orders of magnitude better than previous searches. This sensitivity is made possible by exploiting modern silicon pixel detectors providing high spatial resolution and hodoscopes using scintillating fibres and tiles providing precise timing information at high particle rates.Comment: Research proposal submitted to the Paul Scherrer Institute Research Committee for Particle Physics at the Ring Cyclotron, 104 page

Performance evaluation of a fully depleted monolithic pixel detector chip in 150 nm CMOS technology

The depleted monolithic active pixel sensor (DMAPS) is a new concept integrating full CMOS circuitry onto a (fully) depletable silicon substrate wafer. The realization of prototypes of the DMAPS concept relies on the availability of multiple well CMOS processes and highly resistive substrates. The CMOS foundry ESPROS Photonics offers both and was chosen for prototyping. Two prototypes, EPCB01 and EPCB02, developed in a 150 nm process on a highly resistive n-type wafer of 50 µm thickness, were characterized. The prototypes have 352 square pixels of 40 µm pitch and a small n-well charge collection node with very low capacitance of 5 fF (n+-implantation size: 5 µm x 5 µm) and about 150 transistors per pixel (CSA and discriminator plus a small digital part). The characterization of the prototypes demonstrates the proof of principle of the concept. Prior to irradiation the prototypes show a signal from a minimum ionizing particle ranging from 2400 e- to 3000 e- while the noise is 30 e- due to the low capacitance. After the irradiation of the prototypes with neutrons up to a fluence of 5•1014 neutrons/cm2 the performance suffers from the radiation damage leading to a signal of 1000 e- and a higher noise of 60 e- due to the increase of the leakage current. The detection efficiency of the prototypes reduces from 94 % to 26 % after the fluence of 5•1014 particles/cm2. Due to the small fill factor the detection efficiency shows are strong dependence on the position within the pixel after irradiation. Thus the DMAPS concept with low fill factor can be used for precise vertex reconstruction in High Energy Physics experiments without severe performance loss up to moderate fluences (14 particles/cm2). The expected particle fluences inside of the volume of the upgrade of the ATLAS pixel detector exceed this limit. However, possible applications could be at future linear collider (ILC or CLIC) experiments and B-factories where the low material budget is of particular importance and the fluences are much less and X-ray imaging with low energy photons which would benefit from the good noise performance

The Mu2e undoped CsI crystal calorimeter

The Mu2e experiment at Fermilab will search for Charged Lepton Flavor Violating conversion of a muon to an electron in an atomic field. The Mu2e detector is composed of a tracker, an electromagnetic calorimeter and an external system, surrounding the solenoid, to veto cosmic rays. The calorimeter plays an important role to provide: a) excellent particle identification capabilities; b) a fast trigger filter; c) an easier tracker track reconstruction. Two disks, located downstream of the tracker, contain 674 pure CsI crystals each. Each crystal is read out by two arrays of UV-extended SiPMs. The choice of the crystals and SiPMs has been finalized after a thorough test campaign. A first small scale prototype consisting of 51 crystals and 102 SiPM arrays has been exposed to an electron beam at the BTF (Beam Test Facility) in Frascati. Although the readout electronics were not the final, results show that the current design is able to meet the timing and energy resolution required by the Mu2e experiment.Comment: 6 pages, 8 figures, proceedings of the "Calorimetry for the high energy frontier (CHEF17)" conference, 2-6 October 2017, Lyon, Franc

MEG Upgrade Proposal

We propose the continuation of the MEG experiment to search for the charged lepton flavour violating decay (cLFV) \mu \to e \gamma, based on an upgrade of the experiment, which aims for a sensitivity enhancement of one order of magnitude compared to the final MEG result, down to the $6 \times 10^{-14}$ level. The key features of this new MEG upgrade are an increased rate capability of all detectors to enable running at the intensity frontier and improved energy, angular and timing resolutions, for both the positron and photon arms of the detector. On the positron-side a new low-mass, single volume, high granularity tracker is envisaged, in combination with a new highly segmented, fast timing counter array, to track positron from a thinner stopping target. The photon-arm, with the largest liquid xenon (LXe) detector in the world, totalling 900 l, will also be improved by increasing the granularity at the incident face, by replacing the current photomultiplier tubes (PMTs) with a larger number of smaller photosensors and optimizing the photosensor layout also on the lateral faces. A new DAQ scheme involving the implementation of a new combined readout board capable of integrating the diverse functions of digitization, trigger capability and splitter functionality into one condensed unit, is also under development. We describe here the status of the MEG experiment, the scientific merits of the upgrade and the experimental methods we plan to use.Comment: A. M. Baldini and T. Mori Spokespersons. Research proposal submitted to the Paul Scherrer Institute Research Committee for Particle Physics at the Ring Cyclotron. 131 Page

Three dimensional optofluidic devices for manipulation of particles and cells

Optical forces offer a powerful tool for manipulating single cells noninvasively. Integration of optical functions within microfluidic devices provides a new freedom for manipulating and studying biological samples at the micro scale. In the pursuit to realise such microfluidic devices with integrated optical components, Ultrafast Laser Inscription (ULI) fabrication technology shows great potential. The uniqueness and versatility of the technique in rapid prototyping of 3D complex microfluidic and optical elements as well as the ability to perform one step integration of these elements provides exciting opportunities in fabricating novel devices for biophotonics applications. The work described in this thesis details the development of three dimensional optofluidic devices that can be used for biophotonics applications, in particular for performing cell manipulation and particle separation. Firstly, the potential of optical forces to manipulate cells and particles in ULI microfluidic channels is investigated. The ability to controllably displace particles within a ULI microchannel using a waveguide positioned orthogonal to it is explored in detail. We then prototype a more complex 3D device with multiple functionalities in which a 3D optofluidic device containing a complex microchannel network and waveguides was used for further investigations into optical manipulation and particle separation. The microfluidic channel network and the waveguides within the device possess the capability to manipulate the injected sample fluid through hydrodynamic focusing and optically manipulate the individual particles, respectively. This geometry provided a more efficient way of investigating optical manipulation within the device. Finally, work towards developing a fully optimised 3D cell separator device is presented. Initial functional validation was performed by investigating the capability of the device to route particles through different outlet channels using optical forces. A proof of concept study demonstrates the potential of the device to use for cell separation based on the size of the cells. It was shown that both passive and active cell separation is possible using this device

The NASA SBIR product catalog

The purpose of this catalog is to assist small business firms in making the community aware of products emerging from their efforts in the Small Business Innovation Research (SBIR) program. It contains descriptions of some products that have advanced into Phase 3 and others that are identified as prospective products. Both lists of products in this catalog are based on information supplied by NASA SBIR contractors in responding to an invitation to be represented in this document. Generally, all products suggested by the small firms were included in order to meet the goals of information exchange for SBIR results. Of the 444 SBIR contractors NASA queried, 137 provided information on 219 products. The catalog presents the product information in the technology areas listed in the table of contents. Within each area, the products are listed in alphabetical order by product name and are given identifying numbers. Also included is an alphabetical listing of the companies that have products described. This listing cross-references the product list and provides information on the business activity of each firm. In addition, there are three indexes: one a list of firms by states, one that lists the products according to NASA Centers that managed the SBIR projects, and one that lists the products by the relevant Technical Topics utilized in NASA's annual program solicitation under which each SBIR project was selected

High Spatial Resolution Silicon Detectors for Independent Quality Assurance in Motion Adaptive Radiotherapy and Charged Particle Radiotherapy Energy Verification

Accurate empirical modelling of the treatment beam is necessary to ensure accurate delivery of dose to the intended target site. Dose calculations within the treatment planning system (TPS) for Stereotactic Radiosurgery (SRS) and Stereotactic Radiotherapy (SRT) treatment rely upon accurate beam data. Inaccuracies within the empirical measurements will propagate as errors throughout calculated patient dose distributions (Tyler, 2013). The necessary empirical measurements for beam commissioning include: percentage depth dose (PDD), output factor (OF) and beam profiles. Thus, especially for the consideration of the afore mentioned small radiation fields, it is important to ensure the most appropriate detector is chosen to conduct measurements of the treatment beams to achieve the highest possible accuracy in measurement of beam parameters. Stereotactic Body Radiation Therapy (SBRT) requires precise delineation of the target using modern imaging modalities (MRI, CT etc.), accurate dosimetry to ensure the planned dose is delivered correctly and effective patient immobilisation. For extracranial sites the treatment accuracy is affected by tumour delineation which identifies the extent of the tumour volume and tumour motion resulting from the physical, biological and physiological processes of the human body. Delivery of radiation using highly conformal and small radiation beams presents challenges for dosimetry and quality assurance (Heydarian, 1996), (Das, 2008). To correctly measure dose in a small field an ideal dosimeter must exhibit properties including: small sensitive volume, near water equivalence, minimal beam perturbation and no dose-rate, energy or directional dependence (Pappas, 2008). Also, treatment planning for dose calculation must be conducted using algorithms which can account for the impact of the heterogeneities found in the abdomen and thoracic cavities to ensure calculation of the dose to tissue in regions with complex scattering conditions is accurate (Rubio, 2013)