The Collider Detector at Fermilab (CDF) pursues a broad physics program at Fermilab's Tevatron collider. Between Run II commissioning in early 2001 and the end of operations in September 2011, the ...Tevatron delivered 12fb−1 of integrated luminosity of pp¯ collisions at s=1.96TeV. The physics at CDF includes precise measurements of the masses of the top quark and W boson, measurement of CP violation and Bs mixing, and searches for Higgs bosons and new physics signatures, all of which require heavy flavor tagging with large charged particle tracking acceptance. To realize these goals, in 2001 CDF installed eight layers of silicon microstrip detectors around its interaction region. These detectors were designed for 2–5 years of operation, radiation doses up to 2Mrad (0.02Gy), and were expected to be replaced in 2004. The sensors were not replaced, and the Tevatron run was extended for several years beyond its design, exposing the sensors and electronics to much higher radiation doses than anticipated. In this paper we describe the operational challenges encountered over the past 10 years of running the CDF silicon detectors, the preventive measures undertaken, and the improvements made along the way to ensure their optimal performance for collecting high quality physics data. In addition, we describe the quantities and methods used to monitor radiation damage in the sensors for optimal performance and summarize the detector performance quantities important to CDF's physics program, including vertex resolution, heavy flavor tagging, and silicon vertex trigger performance.
•We have operated the CDF II silicon detector system well beyond its design lifetime.•We describe design of each component, its performance parameters and resource needs.•A history of operational experience and mitigation of encountered problems is given.•Novel methods were found to mitigate wirebond resonance and cooling system corrosion.•Radiation aging effects on silicon sensors from a decade long exposure are presented.
Status of the CDF Run II silicon detector Nahn, S.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2003, Letnik:
511, Številka:
1
Journal Article
Recenzirano
Odprti dostop
A snapshot of the status of the CDF Run II Silicon Detector is presented, with a summary of commissioning issues since the start of Run II, current performance of the detector, and the use of the ...data in both the trigger and offline reconstruction.
Unrecoverable internal failures of modules in the CDF Run2 Silicon detector have been observed since its installation in early 2001. A fraction of these failures has been categorized as infant ...mortality. Other failures occurring later were strongly correlated with fixed trigger conditions. These failures are explained by wire-bonds breaking due to fatigue stress induced by resonant vibration. These resonant vibrations are a direct consequence of the oscillating Lorentz forces induced by the
1.4
T
magnetic field on wire-bonds carrying non-DC current. Changes have been implemented in data-taking procedures in order to minimize the occurrences of such failures and to prolong the lifetime of the detector itself. A more general analysis of the topic has been pursued. Changes in the packaging and assembly processes for future applications have been investigated.
Introduction: Despite the availability of an effective COVID-19 vaccine, uptake had been low in Midwestern Hispanic communities. A small qualitative study was undertaken to better understand ...perceptions of COVID-19 disease and prevention among unvaccinated Hispanic adults. Methods: Individual interviews were conducted, in Spanish, with adults (n = 20) who had not been vaccinated for COVID-19. Interview questions were guided by the Theory of Planned Behavior. Results: Participants (n = 20) were Hispanic adults (male = 5; female = 15). One overarching theme, lack of trust, emerged from the data. Perceived barriers to vaccination included emotions, personal values and myths. Recommendations by trusted health providers and willingness to receive education emerged as facilitators to COVID vaccine uptake. Conclusion: Members of the Kansas City Chapter of National Association of Hispanic Nurses used findings from this study to tailor strategies to enhance vaccine confidence in their local community. The chapter partnered with the local health department and Hispanic-serving organizations to provide COVID-19 education and vaccine access.
New VME based boards are being produced for the Run II of the Collider Detector at Fermilab (CDF). These boards are being developed and tested at both Fermilab and offsite institutions. A software ...framework called CDFVME has been developed in which DAQ code can be easily written to control such boards in a test stand. The framework has been used to perform diagnostics at single board, multi-board, and multi-crate levels. This software framework runs on Unix, Linux and Windows NT platforms with a Java GUI communicating via LAN to multiple intelligent front end VME crates. All distributed processes are managed by a custom CORBA based software. The system has been ported to Motorola 68 K and PPC front end processors running the VxWorks real-time kernel.
The single event upset (SEU) cross section has been measured for 63 MeV protons incident on static memory cells in the CDF SVX3 pipelined silicon strip readout ASIC. The device was fabricated in the ...Honeywell
0.8
μm
RICMOS IV bulk process, and contains a number of cells with minimum gate length transistors to control the mode of operation of the chip. Cross sections per cell of
(4.4±1.8)×10
−16
cm
2
,
(2.1±0.7)×10
−15
cm
2
, and
(3.9±0.9)×10
−15
cm
2
were measured for angles of incidence of 0°, 45°, and 80°, respectively, for cells with
0.8
μm
gate length. The SVX3 SEU rate in Run II at the Fermilab Tevatron was estimated to be sufficiently low that it would not affect the performance of the CDF Silicon Tracker.
Tracking detectors are of vital importance for collider-based high energy physics (HEP) experiments. The primary purpose of tracking detectors is the precise reconstruction of charged particle ...trajectories and the reconstruction of secondary vertices. The performance requirements from the community posed by the future collider experiments require an evolution of tracking systems, necessitating the development of new techniques, materials and technologies in order to fully exploit their physics potential. In this article we summarize the discussions and conclusions of the 2022 Snowmass Instrumentation Frontier subgroup on Solid State and Tracking Detectors (Snowmass IF03).
Status of CDF silicon tracking Nahn, S.
Nuclear physics. Section B, Proceedings supplement,
2003, Letnik:
117
Journal Article
Odprti dostop
A snapshot of the status of the CDF Run II Silicon Detector dated July 2002 is presented, with a summary of commissioning issues since the start of Run II, current performance of the detector, and ...the use of the data in both the trigger and offline reconstruction.
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