214 research outputs found
The PRO1 ASIC for Fast Wilkinson Encoding
Wilkinson conversion of stored samples in large Switch Capacitor Array (SCA)
ASICs, such as used for high speed waveform sampling, has many benefits in
terms of compactness, no missing output codes, low power requirements and
robustness. However such Analog-to-Digital conversions are relatively slow,
limited by the encoder clock speed. By repeating the same fast sampling
technique used by the SCA, combined with a fast priority encoder, significantly
faster conversion is demonstrated for a prototype ASIC designated PRO1. For
8-10 bits of resolution, this technique is compact and requires far fewer
system resources.Comment: 10 pages, 11 figure
The first version Buffered Large Analog Bandwidth (BLAB1) ASIC for high luminosity collider and extensive radio neutrino detectors
Future detectors for high luminosity particle identification and ultra high
energy neutrino observation would benefit from a digitizer capable of recording
sensor elements with high analog bandwidth and large record depth, in a
cost-effective, compact and low-power way. A first version of the Buffered
Large Analog Bandwidth (BLAB1) ASIC has been designed based upon the lessons
learned from the development of the Large Analog Bandwidth Recorder and
Digitizer with Ordered Readout (LABRADOR) ASIC. While this LABRADOR ASIC has
been very successful and forms the basis of a generation of new, large-scale
radio neutrino detectors, its limited sampling depth is a major drawback. A
prototype has been designed and fabricated with 65k deep sampling at
multi-GSa/s operation. We present test results and directions for future
evolution of this sampling technique.Comment: 15 pages, 26 figures; revised, accepted for publication in NIM
High Voltage CMOS Control Interface for Astronomy - Grade Charged Coupled Devices
The Pan-STARRS telescope consists of an array of smaller mirrors viewed by a
Gigapixel arrays of CCDs. These focal planes employ Orthogonal Transfer CCDs
(OTCCDs) to allow on-chip image stabilization. Each OTCCD has advanced logic
features that are controlled externally. A CMOS Interface Device for High
Voltage has been developed to provide the appropiate voltage signal levels from
a readout and control system designated STARGRASP. OTCCD chip output levels
range from -3.3V to 16.7V, with two different output drive strenghts required
depending on load capacitance (50pF and 1000pF), with 24mA of drive and a rise
time on the order of 100ns. Additional testing ADC structures have been
included in this chip to evaluate future functional additions for a next
version of the chip.Comment: 13 pages, 17 gigure
A Monolithic Time Stretcher for Precision Time Recording
Identifying light mesons which contain only up/down quarks (pions) from those
containing a strange quark (kaons) over the typical meter length scales of a
particle physics detector requires instrumentation capable of measuring flight
times with a resolution on the order of 20ps. In the last few years a large
number of inexpensive, multi-channel Time-to-Digital Converter (TDC) chips have
become available. These devices typically have timing resolution performance in
the hundreds of ps regime. A technique is presented that is a monolithic
version of ``time stretcher'' solution adopted for the Belle Time-Of-Flight
system to address this gap between resolution need and intrinsic multi-hit TDC
performance.Comment: 9 pages, 15 figures, minor corrections made, to appear as JINST_008
IceCube's In-Ice Radio Extension: Status and Results
In 2006-2010, several Radio Frequency (RF) detectors and calibration
equipment were deployed as part of the IceCube array at depths between 5 to
1400 meters in preparation for a future large scale GZK neutrino detector.
IceCube's deep holes and well-established data handling system provide a unique
opportunity for deep-ice RF detection studies at the South-Pole. We will
present verification and calibration results as well as a status-review of
ongoing analyses such as ice-properties, RF noise and reconstruction
algorithms.Comment: 4 pages, 6 figures, to appear in the proceedings of the Acoustic and
Radio EeV Neutrino detection Activities (ARENA) 2010 conferenc
An imaging time-of-propagation system for charged particle identification at a super B factory
Super B factories that will further probe the flavor sector of the Standard
Model and physics beyond will demand excellent charged particle identification
(PID), particularly K/pi separation, for momenta up to 4 GeV/c, as well as the
ability to operate under beam backgrounds significantly higher than current B
factory experiments. We describe an Imaging Time-of-Propagation (iTOP) detector
which shows significant potential to meet these requirements. Photons emitted
from charged particle interactions in a Cerenkov radiator bar are internally
reflected to the end of the bar, where they are collected on a compact image
plane using photodetectors with fine spatial segmentation in two dimensions.
Precision measurements of photon arrival time are used to enhance the two
dimensional imaging, allowing the system to provide excellent PID capabilities
within a reduced detector envelope. Results of the ongoing optimization of the
geometric and physical properties of such a detector are presented, as well as
simulated PID performance. Validation of simulations is being performed using a
prototype in a cosmic ray test stand at the University of Hawaii.Comment: 3 pages, 5 figures, submitted to TIPP09 proceeding
AURA - A radio frequency extension to IceCube
The excellent radio frequency transparency of cold polar ice, combined with
the coherent Cherenkov emission produced by neutrino-induced showers when
viewed at wavelengths longer than a few centimeters, has spurred considerable
interest in a large-scale radio-wave neutrino detector array.
The AURA (Askaryan Under-ice Radio Array) experimental effort, within the
IceCube collaboration, seeks to take advantage of the opportunity presented by
IceCube drilling through 2010 to establish the radio frequency technology
needed to achieve 100-1000 km^3 effective volumes.
In the 2006-2007 Austral summer 3 deep in-ice radio frequency (RF) clusters
were deployed at depths of 1300m and 300m on top of the IceCube strings.
Additional 3 clusters will be deployed in the Austral summer of 2008-2009.
Verification and calibration results from the current deployed clusters are
presented, and the detector design and performances are discussed. Augmentation
of IceCube with large-scale 1000km^3sr radio and acoustic arrays would extend
the physics reach of IceCube into the EeV-ZeV regime and offer substantial
technological redundancy.Comment: To appear in the proceedings of the Acoustic and Radio EeV Neutrino
detection Activities (ARENA) 2008 conferenc
Observations of Microwave Continuum Emission from Air Shower Plasmas
We investigate a possible new technique for microwave measurements of
ultra-high energy cosmic ray (UHECR) extensive air showers which relies on
detection of expected continuum radiation in the microwave range, caused by
free-electron collisions with neutrals in the tenuous plasma left after the
passage of the shower. We performed an initial experiment at the AWA (Argonne
Wakefield Accelerator) laboratory in 2003 and measured broadband microwave
emission from air ionized via high energy electrons and photons. A follow-up
experiment at SLAC (Stanford Linear Accelerator Center) in summer of 2004
confirmed the major features of the previous AWA observations with better
precision and made additional measurements relevant to the calorimetric
capabilities of the method. Prompted by these results we built a prototype
detector using satellite television technology, and have made measurements
indicating possible detection of cosmic ray extensive air showers. The method,
if confirmed by experiments now in progress, could provide a high-duty cycle
complement to current nitrogen fluorescence observations of UHECR, which are
limited to dark, clear nights. By contrast, decimeter microwave observations
can be made both night and day, in clear or cloudy weather, or even in the
presence of moderate precipitation.Comment: 15 pages, 13 figure
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