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0.25mm-Thick CCD Packaging for the Dark Energy Survey Camera Array
Abstract: The Dark Energy Survey Camera focal plane array will consist of 62 2k x 4k CCDs with a pixel size of 15 microns and a silicon thickness of 250 microns for use at wavelengths between 400 and 1000 nm. Bare CCD die will be received from the Lawrence Berkeley National Laboratory (LBNL). At the Fermi National Accelerator Laboratory, the bare die will be packaged into a custom back-side-illuminated module design. Cold probe data from LBNL will be used to select the CCDs to be packaged. The module design utilizes an aluminum nitride readout board and spacer and an Invar foot. A module flatness of 3 microns over small (1 sqcm) areas and less than 10 microns over neighboring areas on a CCD are required for uniform images over the focal plane. A confocal chromatic inspection system is being developed to precisely measure flatness over a grid up to 300 x 300 mm. This system will be utilized to inspect not only room-temperature modules, but also cold individual modules and partial arrays through flat dewar windows.
Date:
2006-06~
Creator:
Derylo, Greg; Diehl, H. Thomas & Estrada, Juan
Object Type:
Article
System:
The UNT Digital Library
0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology
Thermophotovoltaic (TPV) diodes fabricated from 0.52eV lattice-matched InGaAsSb alloys are grown by Metal Organic Vapor Phase Epitaxy (MOVPE) on GaSb substrates. 4cm{sup 2} multi-chip diode modules with front-surface spectral filters were tested in a vacuum cavity and attained measured efficiency and power density of 19% and 0.58 W/cm{sup 2} respectively at operating at temperatures of T{sub radiator} = 950 C and T{sub diode} = 27 C. Device modeling and minority carrier lifetime measurements of double heterostructure lifetime specimens indicate that diode conversion efficiency is limited predominantly by interface recombination and photon energy loss to the GaSb substrate and back ohmic contact. Recent improvements to the diode include lattice-matched p-type AlGaAsSb passivating layers with interface recombination velocities less than 100 cm/s and new processing techniques enabling thinned substrates and back surface reflectors. Modeling predictions of these improvements to the diode architecture indicate that conversion efficiencies from 27-30% and {approx}0.85 W/cm{sup 2} could be attained under the above operating temperatures.
Date:
June 9, 2004
Creator:
Dashiell, M. W.; Beausang, J. F.; Nichols, G.; Depoy, D. M.; Danielson, L. R.; Ehsani, H. et al.
Object Type:
Report
System:
The UNT Digital Library
A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION
This paper describes electrical design criteria and first operational results a 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt-peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. A review of these design parameters and the first results of the performance characteristics will be presented.
Date:
June 1, 2001
Creator:
Reass, W. A.; Doss, J. D. & Gribble, R. F.
Object Type:
Article
System:
The UNT Digital Library
2.1 Pan-WCRP Monsoon Modelling Workshop Summary
Ken Sperber led a discussion of the outcome of the Pan-WCRP Monsoon Modelling Workshop that was held at the University of California at Irvine from 15-17 June 2005. At the workshop presentations from key CLIVAR and GEWEX panels were presented to highlight the outstanding problems in modelling the Earth's monsoons. Additionally, presentations from invited experts were given to highlight important aspects of monsoon phenomena and processes, such as low-level jets, air-sea interaction, predictability, observational networks/studies, and model test beds etc. Since all persons attending the CLIVAR AAMP meeting were present for all, or most, of the monsoon workshop, a detailed description of the workshop presentations was not given. Rather, the discussion was focused on the recommendations of the workshop breakout groups and their relevance to CLIVAR AAMP. CLIVAR AAMP endorsed the near-term workshop recommendation of investigating the diurnal cycle using a hierarchy of models a key way forward for promoting CLIVAR/GEWEX interactions. In GCM studies CLIVAR researchers have identified the diurnal cycle as a forced ''mode'' of variability that is poorly represented in terms of amplitude and phase, especially in the case of precipitation. Typical phase errors of 6-12 hours are noted over both land and ocean in GCMs. CLIVAR …
Date:
June 28, 2005
Creator:
Sperber, K R
Object Type:
Report
System:
The UNT Digital Library
2-D or not 2-D, that is the question: A Northern California test
Reliable estimates of the seismic source spectrum are necessary for accurate magnitude, yield, and energy estimation. In particular, how seismic radiated energy scales with increasing earthquake size has been the focus of recent debate within the community and has direct implications on earthquake source physics studies as well as hazard mitigation. The 1-D coda methodology of Mayeda et al. has provided the lowest variance estimate of the source spectrum when compared against traditional approaches that use direct S-waves, thus making it ideal for networks that have sparse station distribution. The 1-D coda methodology has been mostly confined to regions of approximately uniform complexity. For larger, more geophysically complicated regions, 2-D path corrections may be required. The complicated tectonics of the northern California region coupled with high quality broadband seismic data provides for an ideal ''apples-to-apples'' test of 1-D and 2-D path assumptions on direct waves and their coda. Using the same station and event distribution, we compared 1-D and 2-D path corrections and observed the following results: (1) 1-D coda results reduced the amplitude variance relative to direct S-waves by roughly a factor of 8 (800%); (2) Applying a 2-D correction to the coda resulted in up to 40% variance …
Date:
June 6, 2005
Creator:
Mayeda, K; Malagnini, L; Phillips, W S; Walter, W R & Dreger, D
Object Type:
Article
System:
The UNT Digital Library
2 MW upgrade of the Fermilab Main Injector
In January 2002, the Fermilab Director initiated a design study for a high average power, modest energy proton facility. An intensity upgrade to Fermilab's 120-GeV Main Injector (MI) represents an attractive concept for such a facility, which would leverage existing beam lines and experimental areas and would greatly enhance physics opportunities at Fermilab and in the U.S. With a Proton Driver replacing the present Booster, the beam intensity of the MI is expected to be increased by a factor of five. Accompanied by a shorter cycle, the beam power would reach 2 MW. This would make the MI a more powerful machine than the SNS or the J-PARC. Moreover, the high beam energy (120 GeV) and tunable energy range (8-120 GeV) would make it a unique high power proton facility. The upgrade study has been completed and published. This paper gives a summary report.
Date:
June 4, 2003
Creator:
Chou, Weiren
Object Type:
Article
System:
The UNT Digital Library
3.9 GHz superconducting accelerating 9-cell cavity vertical test results
The 3rd harmonic 3.9GHz accelerating cavity was proposed to improve the beam performance of the FLASH (TTF/DESY) facility [1]. In the frame of a collaborative agreement, Fermilab will provide DESY with a cryomodule containing a string of four cavities. In addition, a second cryomodule with one cavity will be fabricated for installation in the Fermilab photo-injector, which will be upgraded for the ILC accelerator test facility. The first 9-cell Nb cavities were tested in a vertical setup and they didn't reach the designed accelerating gradient [2]. The main problem was a multipactor in the HOM couplers, which lead to overheating and quenching of the HOM couplers. New HOM couplers with improved design are integrated in the next 9-cell cavities. In this paper we present all results of the vertical tests.
Date:
June 1, 2007
Creator:
Khabiboulline, Timergali; Cooper, Charles; Dhanaraj, Nandhini; Edwards, Helen; Foley, Mike; Harms, Elvin et al.
Object Type:
Article
System:
The UNT Digital Library
3.9 GHz superconducting accelerating 9-cell cavity vertical test results
None
Date:
June 1, 2007
Creator:
Khabiboulline, Timergali; Cooper, Charles; Dhanaraj, Nandhini; Edwards, Helen; Foley, Mike; Harms, Elvin et al.
Object Type:
Article
System:
The UNT Digital Library
3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface
Gian Fradelizio, a Rice Ph.D. student has completed reprocessing the 3D seismic reflection data acquired at Hill AFB through post-stack depth migration for comparison to the traveltime and waveform tomography results. Zelt, Levander, Fradelizio, and 5 others spent a week at Hill AFB in September 2005, acquiring an elastic wave data set along 2 profiles. We used 60 3-component Galperin mounted 40 Hz geophones recorded by 3 GEOMETRICS Stratavision systems. The seismic source employed was a sledgehammer used to generate transverse, and radial, and vertical point source data. Data processing has begun at Rice to generate S-wave reflection and refraction images. We also acquired surface wave and ground penetrating rada data to complement the elastic wave dataset.
Date:
June 1, 2005
Creator:
Levander, Alan R.
Object Type:
Report
System:
The UNT Digital Library
3-D Spectral IP Imaging: Non-Invasive Characterization DE FG02 96ER 14714
The Earth Resources Laboratory (ERL) performed a broad foundational study of spectral induced polarization (SIP) for site characterization. The project encompassed laboratory studies of microgeometry and chemistry effects on Induced Polarization (IP), an investigation of electromagnetic coupling (emc) noise, and development of 3D modeling and inversion codes. The major finding of the project is that emc noise presents a critical limitation for field implementation of SIP and conventional correction methods are inadequate. The project developed a frequency domain 3D complex resistivity modeling and inversion code Laboratory experiments were conducted to study the effects of solution chemistry and microgeometry on the SIP response of sandstone. Results indicate that changes in chemistry affect the magnitude of the spectral IP response and changes in microgeometry affect the shape of the spectral IP response. The developed physiochemical IP model can be used to invert spectral IP data for an apparent grain size distribution. Laboratory studies over the last twenty years have shown that SIP data must be acquired over several decades of frequency and include frequencies greater than 1kHz. A model of the components of emc noise has been developed and investigation with this model showed that inductive coupling is the most significant component. …
Date:
June 1, 2000
Creator:
Morgan, F. Dale; Rodi, William & Lesmes, David
Object Type:
Report
System:
The UNT Digital Library
3 GeV Booster Synchrotron Conceptual Design Report
Synchrotron light cna be produced from a relativistic particle beam circulating in a storage ring at extremely high intensity and brilliance over a large spectral region reaching from the far infrared regime to hard x-rays. The particles, either electrons or positrons, radiate as they are deflected in the fields of the storage ring bending magnets or of magnets specially optimized for the production of synchrotron light. The synchrotron light being very intense and well collimated in the forward direction has become a major tool in a large variety of research fields in physics, chemistry, material science, biology, and medicine.
Date:
June 2, 2009
Creator:
Wiedemann, Helmut
Object Type:
Report
System:
The UNT Digital Library
3 V manganese oxide electrode materials for lithium batteries.
None
Date:
June 20, 2000
Creator:
Johnson, C. S. & Thackeray, M. M.
Object Type:
Article
System:
The UNT Digital Library
The 4.8 GHz LHC Schottky pick-up system
The LHC Schottky observation system is based on traveling wave type high sensitivity pickup structures operating at 4.8 GHz. The choice of the structure and operating frequency is driven by the demanding LHC impedance requirements, where very low impedance is required below 2 GHz, and good sensitivity at the selected band at 4.8 GHz. A sophisticated filtering and triple down -mixing signal processing chain has been designed and implemented in order to achieve the specified 100 dB instantaneous dynamic range without range switching. Detailed design aspects for the complete systems and test results without beam are presented and discussed.
Date:
June 1, 2007
Creator:
Caspers, Fritz; Jimenez, Jose Miguel; Jones, Rhodri Owain; Kroyer, Tom; Vuitton, Christophe; Hamerla, Timothy W. et al.
Object Type:
Article
System:
The UNT Digital Library
4-D High-Resolution Seismic Reflection Monitoring of Miscible CO2 Injected into a Carbonate Reservoir
The objective of this research project was to acquire, process, and interpret multiple high-resolution 3-D compressional wave and 2-D, 2-C shear wave seismic data in the hopes of observing changes in fluid characteristics in an oil field before, during, and after the miscible carbon dioxide (CO{sub 2}) flood that began around December 1, 2003, as part of the DOE-sponsored Class Revisit Project (DOE No.DE-AC26-00BC15124). Unique and key to this imaging activity is the high-resolution nature of the seismic data, minimal deployment design, and the temporal sampling throughout the flood. The 900-m-deep test reservoir is located in central Kansas oomoldic limestones of the Lansing-Kansas City Group, deposited on a shallow marine shelf in Pennsylvanian time. After 30 months of seismic monitoring, one baseline and eight monitor surveys clearly detected changes that appear consistent with movement of CO{sub 2} as modeled with fluid simulators and observed in production data. Attribute analysis was a very useful tool in enhancing changes in seismic character present, but difficult to interpret on time amplitude slices. Lessons learned from and tools/techniques developed during this project will allow high-resolution seismic imaging to be routinely applied to many CO{sub 2} injection programs in a large percentage of shallow carbonate …
Date:
June 30, 2007
Creator:
Miller, Richard D.; Raef, Abdelmoneam E.; Byrnes, Alan P. & Harrison, William E.
Object Type:
Report
System:
The UNT Digital Library
An 8 GeV H- multi-turn injection system for the Fermilab Main Injector
An 8 GeV superconducting linear accelerator (SCL) has been proposed [1] as a single stage H{sup -} injector into the Main Injector (MI) synchrotron . This would be the highest energy H{sup -} multi-turn injection system in the world. The conceptual design of an injection system has been further refined by addressing transverse phase space painting issues, chicane dipole fields and foil location, foil temperature issues, and initial longitudinal phase space painting simulations. We present the current state of design.
Date:
June 1, 2007
Creator:
Johnson, D. E.; Yoon, P.; Liaw, C. J.; Raparia, D. & Bebee-Wang, J.
Object Type:
Article
System:
The UNT Digital Library
An 8 GeV H- multi-turn injection system for the Fermilab Main Injector
None
Date:
June 1, 2007
Creator:
Johnson, D. E.; Yoon, P.; Liaw, C. J.; Raparia, D. & Bebee-Wang, J.
Object Type:
Article
System:
The UNT Digital Library
An 8-GeV Synchrotron-Based Proton Driver
In January 2002, the Fermilab Director initiated a design study for a high average power, modest energy proton facility. Such a facility is a possible candidate for a construction project in the U.S. starting in the middle of this decade. The key technical element is a new machine, dubbed the ''Proton Driver,'' as a replacement of the present Booster. The study of an 8-GeV synchrotron-based proton driver has been completed and published. This paper will give a summary report, including machine layout and performance, optics, beam dynamics issues, technical systems design, civil construction, cost estimate and schedule.
Date:
June 4, 2003
Creator:
Chou, Weiren
Object Type:
Article
System:
The UNT Digital Library
9-11 Commission Hearing #12, June 16, 2004, Part 1
Recording of the twelfth public hearing held by the National Commission on Terrorist Attacks upon the United States on June 16, 2004 at the NTSB Conference Center in Washington, D.C. The two-day hearing focused on two distinct topics: the 9-11 Plot and the federal government's immediate response to the attacks on September 11, 2001. This section includes the staff statement entitled overview of the enemy in addition to the first panel on Al-Qaeda with testimony from Mary Deborah Doran and Patrick J. Fitzgerald.
Date:
June 16, 2004
Creator:
National Commission on Terrorist Attacks upon the United States
Object Type:
Video
System:
The UNT Digital Library
9-11 Commission Hearing #12, June 16, 2004, Part 2
Recording of the twelfth public hearing held by the National Commission on Terrorist Attacks upon the United States on June 16, 2004 at the NTSB Conference Center in Washington, D.C. The two-day hearing focused on two distinct topics: the 9-11 Plot and the federal government's immediate response to the attacks on September 11, 2001. This section includes the staff statement entitled outline of the 9/11 plot, in addition to the second panel on the outline of the outline of the 9/11 plot with testimony from Jacqueline Maguire, James N. Fitzgerald, and Adam B. Drucker.
Date:
June 16, 2004
Creator:
National Commission on Terrorist Attacks upon the United States
Object Type:
Video
System:
The UNT Digital Library
9-11 Commission Hearing #12, June 17, 2004, Part 1
Recording of the twelfth public hearing held by the National Commission on Terrorist Attacks upon the United States on June 17, 2004 at the NTSB Conference Center in Washington, D.C. The two-day hearing focused on two distinct topics: the 9-11 Plot and the federal government's immediate response to the attacks on September 11, 2001. This section includes the staff statement entitled improvising a homeland defense in addition to the panel on military response on 9/11, with testimony from Richard Myers, Charles Joseph Leidig, and Ralph E. Eberhart.
Date:
June 17, 2004
Creator:
National Commission on Terrorist Attacks upon the United States
Object Type:
Video
System:
The UNT Digital Library
9-11 Commission Hearing #12, June 17, 2004, Part 2
Recording of the twelfth public hearing held by the National Commission on Terrorist Attacks upon the United States on June 17, 2004 at the NTSB Conference Center in Washington, D.C. The two-day hearing focused on two distinct topics: the 9-11 Plot and the federal government's immediate response to the attacks on September 11, 2001. This section concludes the hearing, and includes the panel on FAA response on 9/11, with testimony from Monte Belger, Jeff Griffith, John White, and Benedict Sliney.
Date:
June 17, 2004
Creator:
National Commission on Terrorist Attacks upon the United States
Object Type:
Video
System:
The UNT Digital Library
10 (micro)m and 5 (micro)m Pinhole-Assisted Point-Projection Backlit Imaging for NIF
Pinhole-assisted point-projection backlighting with 10{micro}m and 5 {micro}m pinholes placed a small distance of order 1 mm away from the backlighter produces images with large field of view and high resolution. Pinholes placed closely to high-power backlighter sources can vaporize and close due to x-ray driven ablation, thereby limiting the usefulness of this method. A study of streaked 1-D backlit imaging of 25 {micro}m W wires using the OMEGA laser is presented. The pinhole closure timescale for 10 {micro}m pinholes placed 0.45 mm and 1 mm distant from the backlighter is 1.3 ns and 2.2 ns, respectively. Similar timescales for 5 {micro}m pinholes is also presented. Successful wire imaging prior to pinhole closure is clearly demonstrated.
Date:
June 5, 2001
Creator:
Bullock, A. B.; Landen, O. L. & Bradley, D. K.
Object Type:
Article
System:
The UNT Digital Library
A 15-T Pulsed Solenoid for a High-Power Target Experiment
The MERIT experiment, which ran at CERN in 2007, is a proof-of-principle test for a target system that converts a 4-MW proton beam into a high-intensity muon beam for either a neutrino factory complex or a muon collider. The target system is based on a free mercury jet that intercepts an intense proton beam inside a 15-T solenoidal magnetic field. Here, we describe the design and performance of the 15-T, liquid-nitrogen-precooled, copper solenoid magnet.
Date:
June 23, 2008
Creator:
Kirk, H. G.; Efthymiopoulos, I.; Fabich, A.; Haug, F.; Pereira, H.; Titus, P. et al.
Object Type:
Article
System:
The UNT Digital Library
A 15-T Pulsed Solenoid for a High-Power Target Experiment
The MERIT experiment, to be run at CERN in 2007, is a proof-of-principle test for a target system that converts a 4-MW proton beam into a high-intensity muon beam for either a neutrino factory complex or a muon collider. The target system is based on a free mercury jet that intercepts an intense proton beam inside a 15-T solenoidal magnetic field. Here, we describe the design and initial performance of the 15-T, liquid-nitrogen-precooled, copper solenoid magnet.
Date:
June 26, 2006
Creator:
Kirk, H. G.; Efthymiopoulos, I.; Fabich, A.; Haug, R.; Titus, P.; McDonald, K. T. et al.
Object Type:
Article
System:
The UNT Digital Library