218 Matching Results

Search Results

Advanced search parameters have been applied.

HIGH CHARGE EFFECTS IN SILICON DRIFT DETECTORS WITH LATERAL CONFINEMENT OF ELECTRONS.

Description: A new drift detector prototype which provides suppression of the lateral diffusion of electrons has been tested as a function of the signal charge up to high charge levels, when electrostatic repulsion is not negligible. The lateral diffusion of the electron cloud has been measured for injected charges up to 2 {center_dot} 10{sup 5} electrons. The maximum number of electrons for which the suppression of the lateral spread is effective is obtained.
Date: October 21, 1995
Creator: CASTOLDI,A. & REHAK,P.
Partner: UNT Libraries Government Documents Department

The BTeV pixel and microstrip detector

Description: The BTeV pixel detector is one of the most crucial elements in the BTeV experiment. While the pixel detector is technically challenging, we have made great progress towards identifying viable solutions for individual components of the system. The forward silicon tracker is based on more mature technology and its design has benefited from the experience of other experiments. Nevertheless, we have started an R&D program on the forward silicon tracker and first results are expected some time next year.
Date: June 4, 2003
Creator: Kwan, Simon W
Partner: UNT Libraries Government Documents Department

The SVX II silicon vertex detector at CDF

Description: The Silicon Vertex detector (SVX II) for the CDF experiment at the Tevatron p{anti p} collider is a 3-barrel 5-layer device with double-sided, AC-coupled silicon strip detectors. The readout is based on a custom IC, the SVX3 chip, capable of simultaneous acquisition, digitization and readout operation (dead-timeless). In this paper we report on the SVX II design and project status including mechanical design, frontend electronics, and data acquisition.
Date: December 1, 1998
Creator: Valls, Juan A.
Partner: UNT Libraries Government Documents Department

SVT: an online silicon vertex tracker for the CDF upgrade

Description: The SVT is an online tracker for the CDF upgrade which will reconstruct 2D tracks using information from the Silicon VerteX detector (SVXII) and Central Outer Tracker (COT). The precision measurement of the track impact parameter will then be used to select and record large samples of B hadrons. We discuss the overall architecture, algorithms, and hardware implementation of the system.
Date: July 1, 1997
Creator: Bardi, A.; Belforte, S. & Berryhill, J.
Partner: UNT Libraries Government Documents Department

SVX3: A deadtimeless readout chip for silicon strip detectors

Description: A new silicon strip readout chip called the SVX3 has been designed for the 720,000 channel CDF silicon upgrade at Fermilab. SVX3 incorporates an integrator, analog delay pipeline, ADC, and data sparsification for each of 128 identical channels. Many of the operating parameters are programmable via a serial bit stream, which allows the chip to be used under a variety of conditions. Distinct features of SVX3 include use of a backside substrate contact for optimal ground referencing, and the capability of simultaneous signal acquisition and digital readout allowing deadtimeless operation in the Fermilab Tevatron.
Date: December 1, 1997
Creator: Zimmerman, T.; Huffman, T.; Srage, J.; Stroehmer, R.; Yarema, R.; Garcia-Sciveras, M. et al.
Partner: UNT Libraries Government Documents Department

Noise analysis due to strip resistance in the ATLAS SCT silicon strip module

Description: The module is made out of four 6 cm x 6 cm single sided Si microstrip detectors. Two detectors are butt glued to form a 12 cm long mechanical unit and strips of the two detectors are electrically connected to form 12 cm long strips. The butt gluing is followed by a back to back attachment. The module in this note is the R{phi} module where the electronics is oriented parallel to the strip direction and bonded directly to the strips. This module concept provides the maximum signal-to-noise ratio, particularly when the front-end electronics is placed near the middle rather than at the end. From the noise analysis, it is concluded that the worst-case {Delta}ENC (far-end injection) between end- and center-tapped modules will be 120 to 210 el. rms (9 to 15%) for a non-irradiated detector and 75 to 130 el. rms (5 to 9%) for an irradiated detector, for a metal strip resistance of 10 to 20 {Omega}/cm.
Date: August 1, 1996
Creator: Kipnis, I.
Partner: UNT Libraries Government Documents Department

Preliminary results from the D-Zero silicon vertex beam tests

Description: Extensive tests of the D-Zero silicon vertex detectors and the final version of the SVX-II chip and readout electronics were performed at a test beam facility equipped with a 2 Tesla magnet at FNAL. Preliminary results are reported on the performance of the SVX-II chip, charge collection properties, signal to noise ratio, cluster pulse height and spatial resolution.
Date: October 1, 1997
Creator: Roco, M.T.P.
Partner: UNT Libraries Government Documents Department

The MASDA-X chip - A new multichannel ASIC for readout of pixelated amorphous silicon arrays

Description: The MASDA-X chip is designed specifically for reading out large amorphous silicon pixel arrays used in medical imaging research. Instrumenting these arrays requires a set of digital row address- ing chips to sequentially select the pixel rows for readout, and a set of column readout chips to collect and process the analog charge transferred to each column by the selected pixels. A 32 channel column readout chip, MASDA-R, has previously been designed and successfully imple- mented by Fermilab and the University of Michigan. However, new arrays require an updated readout chip design with much tighter input channel pitch for direct mating to arrays. A new 128 channel chip, MASDA-X, has been designed at Fermilab. This chip incorporates performance improvements along with tighter channel pitch. MASDA-R was designed in the H. P. 0.8 micron process, which will no longer be available. Therefore, MASDA-X has been designed in the H. P. 0.5 micron 3.3V process.
Date: December 1, 1998
Creator: Zimmerman, Tom
Partner: UNT Libraries Government Documents Department

The silicon microstrip tracker for the D0 upgrade

Description: The silicon microstrip tracker is a major element of the D0 detector upgrade at Fermilab. After a general overview of the silicon tracker design, results are presented for a series of detector and electronics performance studies which include beam tests and proton irradiation. Charge sharing and strip-to-strip uniformity studies using an infrared laser are also presented.
Date: December 1, 1998
Creator: Roco, Maria Teresa P.
Partner: UNT Libraries Government Documents Department

The CDF intermediate silicon layers detector

Description: The Intermediate Silicon Layers (ISL) detector is presently being built as part of CDF upgrades. The ISL is a large radius (28 cm) silicon tracker with a total active area of about 3.5 m 2 . The challenge is to build a device which provides precise 3D points introducing a minimal amount of material for the supporting structure. The design and the status of the project are described.
Date: December 1, 1998
Creator: al., S. Donati et
Partner: UNT Libraries Government Documents Department

[Hadroproduction of charmed and bottom mesons (Fermilab experiment E-653): Progress report, April 1, 1986--March 31, 1987]

Description: This progress report presents information on a number of different projects worked on during the reporting period. One project is the design and performance of a multiplicity jump trigger. The prototype consist of an upstream interaction veto detector, a 3/16 inch long graphite target, a pair of before multiplicity detectors, a 1 inch decay region, and finally six after multiplicity detectors. All detectors were 300 micron thick silicon wafers with a 14 mm square active area. A tritium proportional chamber was built to check Simpson`s result regarding evidence for a 17 keV massive neutrino seen in tritium decay. An electrostatic beta spectrograph has been constructed over the past five years. This detector will use hemispherical electrostatic fields to decelerate electrons from tritium beta decay. Integral endpoint spectra will be measured. The objective is to measure the electron antineutrino mass. A wide ranging theoretical program on non-perturbative quantum field theory work has been ongoing. The calculations which are being worked on involve both the electroweak and the strong interactions. In addition research work on a beam drift chamber, beam solid state detectors, and time-of-flight system are reviewed. A resistive plastic, proportional tube, gas hadron calorimeter with pad readout is described. Also the U of Oklahoma`s High Energy Physics group has constructed, tested, and now is operating two SLAC 3081/E emulators, interfaced to a micro-Vax-2. Performance data from this system is described.
Date: December 31, 1987
Partner: UNT Libraries Government Documents Department

The CDF silicon vertex tracker: Online precision tracking of the CDF silicon vertex detector

Description: The Silicon Vertex Tracker is the CDF online tracker which will re- construct 2D tracks using hit positions measured by the Silicon Vertex Detector and Central Outer Chamber tracks found by the eXtremely Fast Tracker. The precision measurement of the track impact parameter will allow triggering on events contain- ing B hadrons. This will allow the investigation of several important problems in B physics, like CP violation and B<sub>s</sub> mixing, and to search for new heavy particles decaying to b{anti b} .
Date: September 17, 1999
Creator: al., W. Ashmanskas et
Partner: UNT Libraries Government Documents Department

The CDF silicon vertex tracker: Online precision tracking of the CDF silicon vertex

Description: The Silicon Vertex Tracker is the CDF online tracker which will re- construct 2D tracks using hit positions measured by the Silicon Vertex Detector and Central Outer Chamber tracks found by the eXtremely Fast Tracker. The precision measurement of the track impact parameter will allow triggering on events contain- ing B hadrons. This will allow the investigation of several important problems in B physics, like CP violation and B<sub>s</sub> mixing, and to search for new heavy particles decaying to b{anti b}.
Date: August 24, 1999
Creator: al., W. Ashmanskas et
Partner: UNT Libraries Government Documents Department

The status of the D-Zero silicon tracker upgrade project

Description: The current status of the silicon tracker for the D0 upgrade project for Run II at the Tevatron is presented. After reviewing the design considerations the status of delivery and testing of the different silicon sensors is presented. The ladder production and assembly process is also discussed.
Date: September 27, 1999
Creator: Lehner, Frank
Partner: UNT Libraries Government Documents Department

The CDF silicon vertex tracker

Description: The Silicon Vertex Tracker (SVT) is presently being built as part of CDF upgrades. It is the online tracker which will reconstruct 2D tracks using information from the Silicon Vertex Detector (SVXII) and the Central Outer Chamber (COT). The precision measurement of the track impact parameter will allow to select high statistics b samples at trigger level and attack the study of CP violation in the b sector (i.e. in the B<sup>0</sup><sub>d</sub> {yields} {pi}<sup>+</sup>{pi}<sup>-</sup> decay) and of B<sup>0</sup><sub>s</sub> mixing. We discuss the overall architecture, algorithms and hardware implementation of the system.
Date: July 12, 1999
Creator: Donati, S.
Partner: UNT Libraries Government Documents Department

An Automatic Lithium Drifting Apparatus for Silicon and Germanium Detectors

Description: Drifting a thick lithium-drifted counter (silicon and germanium) is a time-consuming operation that frequently results in a poor device, owing to inadequate knowledge of progress of the drifting operation. The drifting apparatus described here automatically controls the temperature of the detector that is being drifted to maintain the leakage current at a preselected value. While drifting proceeds, a continuous measurement is made of the distance of the lithium-drifted region from the opposite face of the wafer. When the drifted region reaches 30 mil or less from the back of the wafer a meter indicates the thickness of the undrifted region and, when this thickness falls below a preselected value, the temperature of the detector is automatically reduced to room temperature. The need for constant supervision of the drifting operation is thereby eliminated, and reliance on theoretical drift-rate calculations to predict the drift-through time is avoided. The technique has been applied to the manufacture of lithium-drifted silicon detectors with excellent results. The application of the technique to lithium-drifted germanium {gamma} detectors is also discussed briefly.
Date: February 8, 1964
Creator: Goulding, Fred S. & Hansen, W. L.
Partner: UNT Libraries Government Documents Department

FRONT-END ASIC FOR HIGH RESOLUTION X-RAY SPECTROMETERS.

Description: We present an application specific integrated circuit (ASIC) for high-resolution x-ray spectrometers. The ASIC is designed to read out signals from a pixelated silicon drift detector (SDD). Each hexagonal pixel has an area of 15 mmz and an anode capacitance of less than 100 fF. There is no integrated Field Effect transistor (FET) in the pixel, rather, the readout is done by wirebonding the anodes to the inputs of the ASIC. The ASIC provides 14 channels of low-noise charge amplification, high-order shaping with baseline stabilization, and peak detection with analog memory. The readout is sparse and based on low voltage differential signaling. An interposer provides all the interconnections required to bias and operate the system. The channel dissipates 1.6 mW. The complete 14-pixel unit covers an area of 210 mm{sup 2}, dissipates 12 mW cm{sup -2}, and can be tiled to cover an arbitrarily large detection area. We measured a preliminary resolution of 172 eV at -35 C on the 6 keV peak of a {sup 55}Fe source.
Date: October 27, 2007
Creator: DE GERONIMO,G.; CHEN, W.; FRIED, J.; LI, Z.; PINELLI, D.A.; REHAK, P. et al.
Partner: UNT Libraries Government Documents Department

The Effect of dead-timeless silicon strip readout at CDF II

Description: The Run IIa CDF Silicon Upgrade has recently finished installation. The detector uses revision D of the SVX3 readout IC. This final revision incorporated new features in order to improve the potential of dead-timeless operation. This paper describes measurements of dead-timeless effects on silicon strip readout on the test bench. This paper also describes tests of the dynamic pedestal subtraction circuitry, which is shown to improve greatly the dead-timeless performance of the silicon systems.
Date: March 12, 2002
Creator: al., A. Affolder et
Partner: UNT Libraries Government Documents Department

SVX/silicon detector studies

Description: AC coupled silicon detectors, being used for the DO upgrade, may have substantial voltage across the coupling capacitor. Failed capacitors can present {approximately}50 V to the input of the SVX, Silicon Vertex, device. We measured the effects that failed detector coupling capacitors have on the SVXD (rad soft 3{mu}m), SVXH (rad hard 1.2{mu}m), and SVXIIb (rad soft 1.2{mu}m) amplifier / readout devices. The test results show that neighboring channels saturate when an excessive voltage is applied directly to a SVX channel. We believe that the effects are due to current diffusion within the SVX substrate rather than surface currents on the detectors. This paper discusses the magnitude of the saturation and a possible solution to the problem.
Date: November 1, 1995
Creator: Bagby, L.; Johnson, M.; Lipton, R. & Gu, W.
Partner: UNT Libraries Government Documents Department

Amorphous silicon/crystalline silicon heterojunctions for nuclear radiation detector applications

Description: Results on characterization of electrical properties of amorphous Si films for the 3 different growth methods (RF sputtering, PECVD [plasma enhanced], LPCVD [low pressure]) are reported. Performance of these a-Si films as heterojunctions on high resistivity p-type and n- type crystalline Si is examined by measuring the noise, leakage current, and the alpha particle response of 5mm dia detector structures. It is demonstrated that heterojunction detectors formed by RF sputtered films and PECVD films are comparable in performance with conventional surface barrier detectors. Results indicate that the a-Si/c-Si heterojunctions have the potential to greatly simplify detector fabrication. Directions for future avenues of nuclear particle detector development are indicated.
Date: October 1, 1996
Creator: Walton, J.T.; Hong, W.S.; Luke, P.N.; Wang, N.W. & Ziemba, F.P.
Partner: UNT Libraries Government Documents Department

Silicon Tracking Upgrade at CDF

Description: The Collider Detector at Fermilab (CDF) is scheduled to begin recording data from Run II of the Fermilab Tevatron in early 2000. The silicon tracking upgrade constitutes both the upgrade to the CDF silicon vertex detector (SVX II) and the new Intermediate Silicon Layers (ISL) located at radii just beyond the SVX II. Here we review the design and prototyping of all aspects of these detectors including mechanical design, data acquisition, and a trigger based on silicon tracking.
Date: April 1, 1998
Creator: Kruse, M. C.
Partner: UNT Libraries Government Documents Department