Bradley K. Alpert

National Institute of Standards and Technology

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Joel N. Ullom

National Institute of Standards and Technology

Daniel S. Swetz

National Institute of Standards and Technology

Joseph W. Fowler

University of Colorado Boulder

G. C. Hilton

National Institute of Standards and Technology

D. A. Bennett

National Institute of Standards and Technology

C. D. Reintsema

National Institute of Standards and Technology

Leila R. Vale

National Institute of Standards and Technology

John A. B. Mates

National Institute of Standards and Technology

W. B. Doriese

National Institute of Standards and Technology

E. Ferri

Istituto Nazionale di Fisica Nucleare, Sezione di Milano Bicocca

Cooperative Institutions

National Institute of Standards and Technology

114

University of Colorado Boulder

Istituto Nazionale di Fisica Nucleare, Sezione di Milano Bicocca

Istituto Nazionale di Fisica Nucleare, Sezione di Genova

University of Milano-Bicocca

University of Genoa

National Institute of Standards

SLAC National Accelerator Laboratory

Stanford University

Paul Scherrer Institute

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Information theoretic study on x-ray imaging of integrated circuits in a low photon budget

OSA Imaging and Applied Optics Congress 2021 (3D, COSI, DH, ISA, pcAOP) (2021)

Jungki Song Zachary H. Levine Bradley K. Alpert Michael E. Glinsky Joseph W. Fowler

Physics-aware machine learning (PAML) has proven to be successful in re- trieving object in a low-photon imaging condition. In this study, we take an information theoretic approach to study maximum amount of information (i.e., the imaging capacity) that can be reliably retrieved under photon-starved imaging condition. We formulate a sim- ple problem to derive the imaging capacity using Monte Carlo approach: small integrated circuit objects (made out of two different type of materials) imaged with monochromatic x-rays. The simple problem is useful in that the entropies for priors and measurements can be explicitly computed. It is a simple version of the imaging system proposed in Ref. [3]. The constructed problem will help us understand the limit on photon budget, information gain associated with varying number of scan angles, and optimal PAML algorithm that can approach the theoretic imaging capacity.

Monochromatic color

Photon Counting

10.1364/cosi.2021.ctu2f.7

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A tabletop X-ray tomography instrument for nanometer-scale imaging: reconstructions

Microsystems & Nanoengineering (2023)

Zachary H. Levine Bradley K. Alpert Amber L. Dagel Joseph W. Fowler Edward S. Jimenez

We show three-dimensional reconstructions of a region of an integrated circuit from a 130 nm copper process. The reconstructions employ x-ray computed tomography, measured with a new and innovative high-magnification x-ray microscope. The instrument uses a focused electron beam to generate x-rays in a 100 nm spot and energy-resolving x-ray detectors that minimize backgrounds and hold promise for the identification of materials within the sample. The x-ray generation target, a layer of platinum, is fabricated on the circuit wafer itself. A region of interest is imaged from a limited range of angles and without physically removing the region from the larger circuit. The reconstruction is consistent with the circuit's design file.

Nanometre

SIGNAL (programming language)

X-ray detector

10.1038/s41378-023-00510-6

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Noise-resilient deep tomographic imaging

Zhen Guo Zhiguang Liu Qihang Zhang George Barbastathis Michael E. Glinsky

X-ray tomography is a non-destructive imaging technique that reveals the interior of an object from its projections at different angles. Under sparse-view and low-photon sampling, regularization priors are required to retrieve a high-fidelity reconstruction. Recently, deep learning has been used in X-ray tomography. The prior learned from training data replaces the general-purpose priors in iterative algorithms, achieving high-quality reconstructions with a neural network. Previous studies typically assume the noise statistics of testing data is acquired a priori from training data, leaving the network susceptible to a change in the noise characteristics under practical imaging conditions. In this work, we propose a noise-resilient deep-reconstruction algorithm for X-ray tomography. By training the network with regularized reconstructions from a conventional algorithm, the learned prior shows strong noise resilience without the need for additional training with noisy examples, and allows us to obtain acceptable reconstructions with fewer photons in testing data. The advantages of our framework may further enable low-photon tomographic imaging where long acquisition times limit the ability to acquire a large training set.

Tomographic reconstruction

Regularization

Data set

10.1364/opticaopen.21931557

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HOLMES

The European Physical Journal C (2015)

Bradley K. Alpert M. Balata D. A. Bennett M. Biasotti C. Boragno

The European Research Council has recently funded HOLMES, a new experiment to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the decay of 163Ho. The calorimetric measurement eliminates systematic uncertainties arising from the use of external beta sources, as in experiments with beta spectrometers. This measurement was proposed in 1982 by A. De Rujula and M. Lusignoli, but only recently the detector technological progress allowed to design a sensitive experiment. HOLMES will deploy a large array of low temperature microcalorimeters with implanted 163Ho nuclei. The resulting mass sensitivity will be as low as 0.4 eV. HOLMES will be an important step forward in the direct neutrino mass measurement with a calorimetric approach as an alternative to spectrometry. It will also establish the potential of this approach to extend the sensitivity down to 0.1 eV. We outline here the project with its technical challenges and perspectives.

10.1140/epjc/s10052-015-3329-5

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Citations (139)

Status of HOLMES, an experiment for measuring the nu mass

E. Ferri Bradley K. Alpert M. Balata Daniel Becker D. A. Bennett

One of the major challenges in nowadays particle physics and astrophysics is the determination of the absolute neutrino mass scale. The HOLMES experiment aims at exploiting the calorimetric approach to directly measure the neutrino mass through the kinematic measurement of the decay products of 163 Ho electron capture (EC). The high energy portion of the calorimetric spectrum of this decay is affected by the non-vanishing neutrino mass value. Given the small fraction of events falling the region of interest, to achieve a high experimental sensitivity on the neutrino mass it is important to have a high activity combined with a very small undetected pile-up contribution. To achieve these targets, the final configuration of HOLMES foresees the deployment of a large number of 163 Ho ion-implanted TESs characterized by an ambitiously high activity of 300 Hz each. This contribution will provide an overview on the HOLMES project with its physics reach and technical challenges together with the status of the major tasks that will bring HOLMES to achieve a statistical sensitivity on the neutrino mass as low as 2 eV.

Electron neutrino

10.22323/1.421.0076

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When "Optimal Filtering" Isn't

Applied Superconductivity (2016)

Joseph W. Fowler Bradley K. Alpert W. B. Doriese J. P. Hays-Wehle Young Il Joe

Source

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Legendre Fit to the Reflection Coefficient of a Radiating Rectangular Waveguide Aperture

IEEE Microwave and Wireless Components Letters (2012)

Dylan F. Williams Mohammad Tayeb Ghasr Bradley K. Alpert Zhongxiang Shen Alexander Arsenovic

We accurately calculate the reflection coefficient and normalized admittance of radiating open-ended rectangular waveguides and fit our results with a linear combination of Legendre polynomials. We verify the expression to an accuracy of 0.005 with other calculations and examine the impact of flanges and burrs on the accuracy to which the reflection coefficient can be approximated in practice.

Reflection coefficient

Admittance

Reflection

Aperture (computer memory)

Waveguide

Source

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Nonideal measurement locations in planar near-field antenna metrology

Computer Standards & Interfaces (1999)

Ronald C. Wittmann Bradley K. Alpert M.H. Francis

10.1016/s0920-5489(99)92302-4

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Hybrid Gauss-Trapezoidal Quadrature Rules

SIAM Journal on Scientific Computing (1999)

Bradley K. Alpert

A new class of quadrature rules for the integration of both regular and singular functions is constructed and analyzed. For each rule the quadrature weights are positive and the class includes rules of arbitrarily high-order convergence. The quadratures result from alterations to the trapezoidal rule, in which a small number of nodes and weights at the ends of the integration interval are replaced. The new nodes and weights are determined so that the asymptotic expansion of the resulting rule, provided by a generalization of the Euler--Maclaurin summation formula, has a prescribed number of vanishing terms. The superior performance of the rules is demonstrated with numerical examples and application to several problems is discussed.

Trapezoidal rule

Quadrature (astronomy)

Tanh-sinh quadrature

Clenshaw–Curtis quadrature

Gauss–Jacobi quadrature

10.1137/s1064827597325141

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Citations (220)

Measuring the electron neutrino mass with improved sensitivity: the HOLMES experiment

Journal of Instrumentation (2017)

A. Giachero Bradley K. Alpert Daniel Becker D. A. Bennett M. Biasotti

HOLMES is a new experiment aiming at directly measuring the neutrino mass with a sensitivity below 2 eV . HOLMES will perform a calorimetric measurement of the energy released in the decay of 163Ho. The calorimetric measurement eliminates systematic uncertainties arising from the use of external beta sources, as in experiments with spectrometers. This measurement was proposed in 1982 by A. De Rujula and M. Lusignoli, but only recently the detector technological progress has allowed to design a sensitive experiment. HOLMES will deploy a 1000 pixels array of low temperature microcalorimeters with implanted 163Ho nuclei. HOLMES, besides being an important step forward in the direct neutrino mass measurement with a calorimetric approach, will also establish the potential of this approach to extend the sensitivity down to 0.1 eV and lower. The detectors used for the HOLMES experiment will be Mo/Cu bilayers TESs (Transition Edge Sensors) on SiNx membrane with gold absorbers. Microwave multiplexed rf-SQUIDs are the best available technique to read out large array of such detectors. An extensive R&D activity is in progress in order to maximize the multiplexing factor while preserving the performances of the individual detectors. To embed the 163Ho into the gold absorbers a custom mass separator ion implanter is being developed. The current activities are focused on the the single detector performances optimization and on the 163Ho isotope production and embedding. A preliminary measurement of a sub-array of 4× 16 detectors is planned late in 2017. In this contribution we present the HOLMES project with its technical challenges, its status and perspectives.

10.1088/1748-0221/12/02/c02046

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Citations (16)