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NASA NTRS2010

Separating Gravitational Wave Signals from Instrument Artifacts

Central to the gravitational wave detection problem is the challenge of separating features in the data produced by astrophysical sources from features produced by the detector. Matched filtering provides an optimal solution for Gaussian noise, but in practice, transient noise excursions or "glitches" complicate the analysis. Detector diagnostics and coincidence tests can be used to veto many glitches which may otherwise be misinterpreted as gravitational wave signals. The glitches that remain can lead to long tails in the matched filter search statistics and drive up the detection threshold. Here we describe a Bayesian approach that incorporates a more realistic model for the instrument noise allowing for fluctuating noise levels that vary independently across frequency bands, and deterministic "glitch fitting" using wavelets as "glitch templates", the number of which is determined by a trans-dimensional Markov chain Monte Carlo algorithm. We demonstrate the method's effectiveness on simulated data containing low amplitude gravitational wave signals from inspiraling binary black hole systems, and simulated non-stationary and non-Gaussian noise comprised of a Gaussian component with the standard LIGO/Virgo spectrum, and injected glitches of various amplitude, prevalence, and variety. Glitch fitting allows us to detect significantly weaker signals than standard techniques.

Littenberg, Tyson B.↗

DOE OSTI2021

Sensitivity of future liquid argon dark matter search experiments to core-collapse supernova neutrinos

Future liquid-argon DarkSide-20k and Argo detectors, designed for direct dark matter search, will be sensitive also to core-collapse supernova neutrinos, via coherent elastic neutrino-nucleus scattering. This interaction channel is flavor-insensitive with a high-cross section, enabling for a high-statistics neutrino detection with target masses of ~50 t and ~360 t for DarkSide-20k and Argo respectively. Thanks to the low-energy threshold of ~0.5 keVnr achievable by exploiting the ionization channel, DarkSide-20k and Argo have the potential to discover supernova bursts throughout our galaxy and up to the Small Magellanic Cloud, respectively, assuming a 11-M progenitor star. In this work, we report also on the sensitivity to the neutronization burst, whose electron neutrino flux is suppressed by oscillations when detected via charged current and elastic scattering. Finally, the accuracies in the reconstruction of the average and total neutrino energy in the different phases of the supernova burst, as well as its time profile, are also discussed, taking into account the expected background and the detector response.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2024

Search For Low-Mass Quark-Antiquark Resonances Produced With an Initial State Photon at 13 TeV Using the CMS Detector

We present a search for low-mass narrow qq̅ resonances. This search uses data from LHC pp collisions at a center of mass of 13 TeV in Run 2, and corresponds to an integrated luminosity of 137 fb^{-1}, currently using 10\% of data. Utilizing full Run 2 data allows the use of a lower photon pT threshold trigger than a previous analysis performed with only 2016 data, allowing this analysis to be more sensitive to resonances in the low mass region. We require an initial state photon recoiling against the narrow resonance, leading to the resonance having a high transverse momentum. The high pT decay products of the resonance collimate and are reconstructed as a single large jet with an internal two-pronged substructure. A two-pronged dijet score based on the ParticleNet tagger is used to select jets with two-pronged substructure. The background is estimated via a data-driven method using a transfer factor between the distributions which fail and pass the two-pronged substructure requirement. The new physics signal is searched for as a narrow peak excess above the Standard Model backgrounds in the jet mass spectrum.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

NASA NTRS1989

Reexamination of data from the asteroid/meteoroid detector

The discovery of the existence of cosmoids, a class of meteoroid in near hyperbolic orbits, was made in a reevaluation of the Sisyphus Experiment on Pioneer 10 and 11. This experiment measured the spontaneous jetting of cosmoids and showed that the dispersion and increase in brightness occurs in microseconds and lasts only briefly. Cosmoid jetting caused multiple telescope thresholds to be exceeded simultaneously which explains the earlier inabilty to compute trajectories from the measured times in the fields of view. A new calculation correlated the Sisyphus individual event measurements with the zodiacal light. That the meteoroid population is dominated by cosmoids is demonstrated. Reported telescopic small comets, measured by a similar optical technique, appear consistent with the Sisyphus results. Characteristic jetting times measured by Sisyphus also show that the volatile cosmoids could not survive in short period orbits.

Soberman, Robert K.↗

DOE OSTI2024

Search For Low-Mass Quark-Antiquark Resonances Produced With an Initial State Photon at 13 TeV Using the CMS Detector

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2015

Recent development of the Multi-Grid detector for large area neutron scattering instruments

Most of the Neutron Scattering facilities are committed in a continuous program of modernization of their instruments, requiring large area and high performance thermal neutron detectors. Beside scintillators detectors, {sup 3}He detectors, like linear PSDs (Position Sensitive Detectors) and MWPCs (Multi-Wires Proportional Chambers), are the most current techniques nowadays. Time Of Flight instruments are using {sup 3}He PSDs mounted side by side to cover tens of m{sup 2}. As a result of the so-called '{sup 3}He shortage crisis{sup ,} the volume of 3He which is needed to build one of these instruments is not accessible anymore. The development of alternative techniques requiring no 3He, has been given high priority to secure the future of neutron scattering instrumentation. This is particularly important in the context where the future ESS (European Spallation Source) will start its operation in 2019-2020. Improved scintillators represent one of the alternative techniques. Another one is the Multi-Grid introduced at the ILL in 2009. A Multi-Grid detector is composed of several independent modules of typically 0.8 m x 3 m sensitive area, mounted side by side in air or in a vacuum TOF chamber. One module is composed of segmented boron-lined proportional counters mounted in a gas vessel; the counters, of square section, are assembled with Aluminium grids electrically insulated and stacked together. This design provides two advantages: First, magnetron sputtering techniques can be used to coat B{sub 4}C films on planar substrates, and second, the neutron position along the anode wires can be measured by reading out individually the grid signals with fast shaping amplifiers followed by comparators. Unlike charge division localisation in linear PSDs, the individual readout of the grids allows operating the Multi-Grid at a low amplification gain, hence this detector is tolerant to mechanical defects and its production accessible to laboratories equipped with standard equipment. Prototypes of different configurations and sizes have been developed and tested. A demonstrator, with a sensitive area of 0.8 m x 3 m, has been studied during the CRISP European project; it contains 1024 grids, and a surface of isotopically enriched B{sub 4}C film close to 80 m{sup 2}. Its size represented a challenge in terms of fabrication and mounting of the detection elements. Another challenge was to make the gas chamber mechanically compatible with operation in a vacuum TOF chamber. Optimal working condition of this detector was achieved by flushing Ar-CO{sub 2} at a pressure of 50 mbar, and by applying 400 Volts on the anodes. This unusual gas pressure allows to greatly simplifying the mechanics of the gas vessel in vacuum. The detection efficiency has been measured with high precision for different film thicknesses. 52% has been measured at 2.5 Angstrom, in good agreement with the MC simulation. A high position resolution has been achieved by centre of gravity measurement of the TOT (Time-Over-Threshold) signals between neighbouring grids. These results, as well as other detection parameters, including gamma sensitivity and spatial uniformity, will be presented. (author)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2020

Sensitivity of future liquid argon dark matter search experiments to core-collapse supernova neutrinos

Future liquid-argon DarkSide-20k and ARGO detectors, designed for direct dark matter search, will be sensitive also to core-collapse supernova neutrinos, via coherent elastic neutrino-nucleus scattering. This interaction channel is flavor-insensitive with a high-cross section, enabling for a high-statistics neutrino detection with target masses of $\sim$50~t and $\sim$360~t for DarkSide-20k and ARGO, respectively. Thanks to the low-energy threshold of $\sim$0.5~keV$_{nr}$ achievable by exploiting the ionization channel, DarkSide-20k and ARGO have the potential to discover supernova bursts throughout our galaxy and up to the Small Magellanic Cloud, respectively, assuming a 11-M$_{\odot}$ progenitor star. We report also on the sensitivity to the neutronization burst, whose electron neutrino flux is suppressed by oscillations when detected via charged current and elastic scattering. Finally, the accuracies in the reconstruction of the average and total neutrino energy in the different phases of the supernova burst, as well as its time profile, are also discussed, taking into account the expected background and the detector response.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2018

Development of a Massive, Highly Multiplexible, Phonon-Mediated Particle Detector Using Kinetic Inductance Detectors

Here, we present a status update on the development of a phonon-mediated particle detector using kinetic inductance detector (KID). The design is intended for $\mathscr {O}(1)$ kg substrate, using $\mathscr {O}(10^{2})$ KIDs on a single readout line, to image the athermal phonon distribution at < 1 mm position resolution and $\mathscr {O}(10)$ eV energy resolution. The design specification is set by the need to improve position reconstruction fidelity while maintaining low energy threshold for future rare-event searches such as for low-mass dark matter. Furthermore, we report on the design, which shows negligible crosstalk and > 95% inductor current uniformity, using the coplanar waveguide feedline, ground shield, and a new class of KIDs with symmetric coplanar stripline (sCPS) inductor. The multiplexing is designed upon the frequency-geometry relation we develop for the sCPS KIDs. We introduce the fabrications of the Nb RF assessment prototypes and the high phonon collection efficiency Al–Nb devices. We achieve $\lesssim $ 0.07% frequency displacement on a 80-KID RF assessment prototype, and the result indicates that we may place more than 180 resonances in our 0.4 GHz readout band with minimal frequency misordering. The coupling quality factors are $\sim $ 10 $^{5}$ as designed. Finally, we update our work in progress in fabricating the $\mathscr {O}(10^{2})$ KID, bi-material, $\mathscr {O}(1)$ kg detectors, and the expected position and energy resolutions.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

NASA NTRS2010

Photon Counting Using Edge-Detection Algorithm

New applications such as high-datarate, photon-starved, free-space optical communications require photon counting at flux rates into gigaphoton-per-second regimes coupled with subnanosecond timing accuracy. Current single-photon detectors that are capable of handling such operating conditions are designed in an array format and produce output pulses that span multiple sample times. In order to discern one pulse from another and not to overcount the number of incoming photons, a detection algorithm must be applied to the sampled detector output pulses. As flux rates increase, the ability to implement such a detection algorithm becomes difficult within a digital processor that may reside within a field-programmable gate array (FPGA). Systems have been developed and implemented to both characterize gigahertz bandwidth single-photon detectors, as well as process photon count signals at rates into gigaphotons per second in order to implement communications links at SCPPM (serial concatenated pulse position modulation) encoded data rates exceeding 100 megabits per second with efficiencies greater than two bits per detected photon. A hardware edge-detection algorithm and corresponding signal combining and deserialization hardware were developed to meet these requirements at sample rates up to 10 GHz. The photon discriminator deserializer hardware board accepts four inputs, which allows for the ability to take inputs from a quadphoton counting detector, to support requirements for optical tracking with a reduced number of hardware components. The four inputs are hardware leading-edge detected independently. After leading-edge detection, the resultant samples are ORed together prior to deserialization. The deserialization is performed to reduce the rate at which data is passed to a digital signal processor, perhaps residing within an FPGA. The hardware implements four separate analog inputs that are connected through RF connectors. Each analog input is fed to a high-speed 1-bit comparator, which digitizes the input referenced to an adjustable threshold value. This results in four independent serial sample streams of binary 1s and 0s, which are ORed together at rates up to 10 GHz. This single serial stream is then deserialized by a factor of 16 to create 16 signal lines at a rate of 622.5 MHz or lower for input to a high-speed digital processor assembly. The new design and corresponding hardware can be employed with a quad-photon counting detector capable of handling photon rates on the order of multi-gigaphotons per second, whereas prior art was only capable of handling a single input at 1/4 the flux rate. Additionally, the hardware edge-detection algorithm has provided the ability to process 3-10 higher photon flux rates than previously possible by removing the limitation that photoncounting detector output pulses on multiple channels being ORed not overlap. Now, only the leading edges of the pulses are required to not overlap. This new photon counting digitizer hardware architecture supports a universal front end for an optical communications receiver operating at data rates from kilobits to over one gigabit per second to meet increased mission data volume requirements.

Gin, Jonathan W.↗

DOE OSTI2024

Low Energy Neutron-induced Charged-particle (Z) (LENZ) instrument development with a focus on pulse shape discrimination for low-energy charged particles

To study neutron-induced charged-particle reactions with high precision, the Low Energy Neutron-induced Charged-particle (Z) instrument (LENZ) was developed at the Los Alamos Neutron Science Center. For the interest of measuring (n,p) and (n, α) reactions simultaneously, Pulse Shape Discrimination methods were investigated to identify different charged particles in the energy range of 3 - 20 MeV and improve signal-to-background ratios using Double-sided Silicon Strip Detectors and waveform digitizers. The risetime and pulse shape properties of detected charged particles were characterized for various silicon detector’s thickness with different orientations. During the post-processing of waveforms, we implemented different digital filters for effective particle identifications and improved energy- and timing- resolutions. We validated the optimized digital filters and pulse shape analyses, via measurements with 228 Th and 229 Th calibration sources, proton-induced reactions on a 7 LiF target, and neutron-induced reactions on CH 2 , Ta 2 O 5 , 58 Ni, and 6 LiF/ 59 Ni targets at the time-of-flight facility, LANSCE. In conclusion, the summary of effective thresholds and Figure of Merits on separating different charged particles is reported.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2019

Constructing a Network Fundamental Diagram: Synthetic Origin–Destination Approach

The Network Fundamental Diagram (NFD) is significantly used in traffic monitoring and control. One obstacle to a wider application of NFDs in network control is the difficulty of obtaining data from all vehicles traveling in the network to construct an accurate NFD. One solution is to estimate the NFD using data from only a fraction of vehicles (i.e., probe vehicles), where the probe vehicle market penetration rate (MPR) needs to be estimated. A previous study conducted by the authors demonstrated that a distance or time weighted harmonic mean was needed to estimate the flow- and density-based MPRs, respectively using a pairing k-mean clustering approach. This paper introduces another approach that utilizes probe vehicle and observed link volume data to estimate the MPR. A heuristic model is proposed to identify the optimum locations from which to collect link traffic volume data for use in the MPR estimation. The estimated MPR can then be used to construct the NFD. Results show that these models can accurately estimate the NFD with limited probe vehicle and link traffic volume data. Accordingly, the models can be used in the field to estimate the NFD using readily available loop detector and probe vehicle data. The ideal locations for traffic volume data collection can also be proactively chosen to generate optimum estimation results. Since the models proposed here show no significant gains with an increased magnitude of collected data after a certain threshold, they will be helpful, particularly when large-scale data collection is not affordable or realistic.

42 ENGINEERING↗

DOE OSTI2023

TPC Test-stands: An Overview & Future Prospects

The DUNE near detector design in Phase II will include a magnetized high-pressure gaseous-argon TPC (HPgTPC) surrounded by a calorimeter, called ND-GAr. ND-GAr is designed to provide fine-grained tracking, and due to its low detection threshold, it will be able to constrain one of the least-understood uncertainties for oscillation analysis: nuclear effects in argon at the neutrino interaction vertex. This talk will provide an overview of and an outlook about the ongoing R&D efforts in the context of the existing test stands that are evaluating the various readout system options for DUNE ND-GAr.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2019

CONSTRUCTING A NETWORK FUNDAMENTAL DIAGRAM: A SYNTHETIC ORIGIN-DESTINATION APPROACH

The Network Fundamental Diagram (NFD) is increasingly used in traffic monitoring and control. One obstacle to a wider application of NFDs in network control is the difficulty of obtaining data from all vehicles traveling in the network to construct an accurate NFD. One solution is to estimate the NFD using data from only a fraction of vehicles (i.e., probe vehicles), where the probe vehicle market penetration rate (MPR) needs to be estimated. A previous study conducted by the authors demonstrated that a distance or time weighted harmonic mean was needed to estimate the flow- and density-based MPRs, respectively using a pairing k-mean clustering approach. This paper proposes another approach that utilizes probe vehicle and observed link volume data to estimate the MPR. A heuristic model is proposed to identify the optimum locations from which to collect link traffic volume data for use in the MPR estimation. The estimated MPR can then be used to construct the NFD. Results show that these models can accurately estimate the NFD with limited probe vehicle and link traffic volume data. Accordingly, the models can be used in the field to estimate the NFD using readily available loop detector and probe vehicle data. The ideal locations for traffic volume data collection can also be proactively chosen to generate optimum estimation results. Since the models proposed here show no significant gains with an increased magnitude of collected data after a certain threshold, they will be helpful, particularly when large-scale data collection is not affordable or realistic.

Spatial Analysis, Market Penetration Rate, NFD, Sy↗

DOE OSTI2012

Exclusive Kaon Electroproduction in Hall C at JLab 12 GeV and EIC

The additional flavor degree of freedom in the H($e,e^\prime K^+$)$\Lambda$/$\Sigma^0$ reactions provides a unique opportunity to study the mechanism underlying strangeness production and the transition from hadronic to partonic degrees of freedom in exclusive processes. However, due to the lack of experimental facilities, the potential of these reactions has not been fully exploited to date. The Jefferson Lab 12 GeV upgrade provides the energies needed for precision kaon cross section measurements in the valence quark region in Hall C. A new threshold aerogel Cerenkov detection system provides a simple and economical option for the kaon identification. Beyond the valence quark region, the first studies of strange sea quarks could be carried out at a future facility like an Electron Ion Collider (EIC). A Detector of Internally Reflected Cherenkov light (DIRC) offers a geometrically compact option for particle ID over the full range of kaon momenta. In this talk I will present the current status and discuss the outlook on future studies of strange quarks with kaon electroproduction as well as the particle identification requirements for each of these stages.

Hlavin, Nathaniel↗

DOE OSTI2025

A sub-5 ps jitter time-to-digital converter ASIC with back-gate delay tuning in 22 nm CMOS

We present the design of a Time-to-Digital Converter (TDC) ASIC together with performance characterization results at cryogenic temperature (6-8 K), and at room temperature using emulated Low-Gain Avalanche Detector (LGAD) signals. The TDC design uses a two-step architecture with a ring-oscillator based counter and a Vernier delay line fine TDC. The TDC is implemented in an FD-SOI process, and back-gate tuning is used not only to correct threshold variation due to cryogenic operation, but also as a novel way to tune TDC delay elements with very little overhead. Using this technique, we demonstrate a design with very low power (0.5 mW) and area (0.003 mm 2 ). We present test results using the Fermilab Constant Fraction Discriminator (FCFD) ASIC to produce discriminated signals from an internal charge injection mechanism that mimics the waveform and signal amplitude of minimum ionizing particles impinging on LGAD sensors. We characterize the time precision of the full system and verify that the TDC ASIC contributes a negligible amount to the total system time precision, fully consistent with the expected jitter contribution of less than 5 ps. In conclusion, the results presented here demonstrate the utility of our TDC for applications in physics and quantum communications.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2021

Comparative evaluation of analogue front-end designs for the CMS Inner Tracker at the High Luminosity LHC

The CMS Inner Tracker, made of silicon pixel modules, will be entirely replaced prior to the start of the High Luminosity LHC period. One of the crucial components of the new Inner Tracker system is the readout chip, being developed by the RD53 Collaboration, and in particular its analogue front-end, which receives the signal from the sensor and digitizes it. Three different analogue front-ends (Synchronous, Linear, and Differential) were designed and implemented in the RD53A demonstrator chip. A dedicated evaluation program was carried out to select the most suitable design to build a radiation tolerant pixel detector able to sustain high particle rates with high efficiency and a small fraction of spurious pixel hits. The test results showed that all three analogue front-ends presented strong points, but also limitations. The Differential front-end demonstrated very low noise, but the threshold tuning became problematic after irradiation. Moreover, a saturation in the preamplifier feedback loop affected the return of the signal to baseline and thus increased the dead time. The Synchronous front-end showed very good timing performance, but also higher noise. For the Linear front-end all of the parameters were within specification, although this design had the largest time walk. This limitation was addressed and mitigated in an improved design. The analysis of the advantages and disadvantages of the three front-ends in the context of the CMS Inner Tracker operation requirements led to the selection of the improved design Linear front-end for integration in the final CMS readout chip.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2015

Dark matter search with CUORE-0 and CUORE

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale experiment made of TeO₂ bolometers that will probe the neutrinoless double beta decay of ¹³⁰Te. Excellent energy resolution, low threshold and low background make CUORE sensitive to nuclear recoils, allowing a search for dark matter interactions. With a total mass of 741 kg of TeO₂, CUORE can search for an annual modulation of the counting rate at low energies. We present data obtained with CUORE-like detectors and the prospects for a dark matter search in CUORE-0, a 40-kg prototype, and CUORE.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2016

Summary Report: NMSBA CY 2016 - AEgis Technologies Group Inc. #12458.

AEgis requires large area partial mirror optics consisting of partially reflecting optical coatings on large dimension substrates for high energy laser (HEL) applications. The partial mirrors should transmit nearly the same small fraction of HEL radiation incident from a wide range of angles of incidence (AOIs), and the laser-induced damage threshold (LIDT) of the coatings should be high enough for them to be able to withstand direct exposure to near infrared CW HEL radiation at multi-kilowatt/cm2 power levels. The transmitted fraction of incident HEL radiation should reach an array of detectors at power levels high enough for reliable detection but low enough to not damage the detectors. The reflected fraction of incident HEL radiation should scatter into a divergent pattern so as to be eye safe at a distance of ~ 200 m from the mirror in the case of 100 kilowatt incident laser power. The detector array together with the partial mirror optic and possible additional optics that provide divergent scattering of reflected HEL radiation constitute what AEgis refers to as a target board. The target board use environment may vary from benign, indoor laboratory conditions to harsh, outdoor conditions in tests on the ground as well as in air. Under this NMSBA project, Sandia agreed to apply its extensive expertise and capability in the design and production of high LIDT coatings on large dimension optics for high power pulsed laser radiation to advise and assist AEgis in the design and development of high LIDT coatings for the partial mirror optic. Sandia and AEgis met several times to discuss the partial mirror and target board requirements, and Sandia was guided in its work by these discussions as well as by the partial mirror and target board requirement summaries of Tables 1 and 2, respectively, that were provided by AEgis.

47 OTHER INSTRUMENTATION↗