Dr. Brian W. Grefenstette Profile

Dr. Brian W. Grefenstette

at Caltech

SPIE Involvement:

Author

Publications (26)

SPIE Journal Paper | 26 October 2023

Wavelet-based image decomposition method for NuSTAR stray light background studies

Andrey Mukhin, Roman Krivonos, Alexey Vikhlinin, Brian Grefenstette, Kristin Madsen, Daniel Wik

JATIS, Vol. 9, Issue 04, 048001, (October 2023) https://doi.org/10.1117/12.10.1117/1.JATIS.9.4.048001

KEYWORDS: Wavelets, Sensors, Stray light, X-rays, X-ray detectors, Image sensors, X-ray imaging, Convolution, X-ray telescopes, Telescopes

Read Abstract +

Proceedings Article | 5 October 2023 Poster + Paper

Background simulations for the high energy x-ray probe (HEX-P)

Kristin Madsen, Henrike Fleischhack, Daniel Violette, Brian Grefenstette, Andreas Zoglauer, Jonathan Arenberg, Benjamin Donovan, Patrick Morrissey, Daniel Stern

Proceedings Volume 12678, 126781B (2023) https://doi.org/10.1117/12.2676891

KEYWORDS: Particles, Simulations, X-rays, Equipment, Design and modelling, Attenuation, Telescopes, Sensors

Read Abstract +

Proceedings Article | 5 October 2023 Presentation + Paper

The high-energy x-ray probe (HEX-P)

Patrick Morrissey, Kristin Madsen, Rashied Amini, Douglas Dawson, Brian Grefenstette, Alex Abramovici, Saptarshi Bandyopadhyay, Guillem Casadesus Vila, Steve Franklin, William Johnson, Sharon Kedar, Marc Lane, Karen Lee, Miles Smith, Daniel Stern, Steven Zusack, Jonathan Arenberg, Mike McEachen, Lance McCreary, Jeff Rodgers, Diogo Coutinho, Johannes Müeller-Seidlitz, Kirpal Nandra, Peter Predehl, Rafael Strecker, Lea Dauner, Steve Kenyon, Paul Markie, William Zhang, Stefano Basso, Alberto Moretti, Giovanni Pareschi, Daniele Spiga, Giuseppe Valsecchi, Dervis Vernani

Proceedings Volume 12678, 126780H (2023) https://doi.org/10.1117/12.2676988

KEYWORDS: Design and modelling, Space operations, Cameras, Mirrors, X-rays, Telescopes, Sensors, Metrology, Astronomical instrumentation

Read Abstract +

Proceedings Article | 27 September 2023 Presentation

Ultraviolet CMOS sensors with integrated filter coatings for the UVEX mission

John Hennessy, Robin Rodríguez, April Jewell, Michael Hoenk, Shouleh Nikzad, Brian Grefenstette, Timothee Greffe, Roger Smith, Hannah Earnshaw, Fiona Harrison

Proceedings Volume 12678, 126780K (2023) https://doi.org/10.1117/12.2677968

KEYWORDS: Optical coatings, Ultraviolet radiation, Tunable filters, CMOS sensors, Atomic layer deposition, Far ultraviolet, Optical sensors, Fabrication, Dielectrics, Coating thickness

Read Abstract +

SPIE Journal Paper | 22 December 2022

Properties of Redlen cadmium zinc telluride with respect to x-ray spectroscopy

Sean N. Pike, Milan Sharma Mandigo-Stoba, Fiona Harrison, Walter Cook, Brian Grefenstette, Hiromasa Miyasaka

JATIS, Vol. 8, Issue 04, 046002, (December 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.4.046002

KEYWORDS: Spectral resolution, X-rays, Zinc, Cadmium, Spectroscopy, Americium, Crystals, Europium, Capacitors, Clouds

Read Abstract +

SPIE Journal Paper | 6 December 2022 Open Access

NuSTAR non-x-ray background

Brian Grefenstette, Kristin Madsen, Hiromasa Miyasaka, Andreas Zoglauer

JATIS, Vol. 8, Issue 04, 047001, (December 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.4.047001

KEYWORDS: X-rays, Solar processes, Sun, Equipment, Solar radiation, Particles, Tunable filters, Satellites, X-ray telescopes, Telescopes

Read Abstract +

DOWNLOAD PAPER

SPIE Journal Paper | 29 September 2022 Open Access

Effective area calibration of the Nuclear Spectroscopic Telescope Array

Kristin Madsen, Karl Forster, Brian Grefenstette, Fiona Harrison, Hiromasa Miyasaka

JATIS, Vol. 8, Issue 03, 034003, (September 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.3.034003

KEYWORDS: Calibration, Sensors, Telescopes, Spectroscopy, Vignetting, Data modeling, Absorption, Platinum, Quantum efficiency, X-rays

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 29 August 2022 Presentation + Paper

Characterization of low light performance of a CMOS sensor for ultraviolet astronomical applications

Timothee Greffe, Roger Smith, Myles Sherman, Fiona Harrison, Hannah Earnshaw, Brian Grefenstette, John Hennessy, Shouleh Nikzad

Proceedings Volume 12191, 121910E (2022) https://doi.org/10.1117/12.2629198

KEYWORDS: Sensors, Cadmium sulfide, Photons, CMOS sensors, Ultraviolet radiation, Video, Charge-coupled devices, Monte Carlo methods, Interference (communication), Astronomy

Read Abstract +

Proceedings Article | 29 August 2022 Presentation + Paper

High dynamic range techniques for astronomical applications of CMOS devices

Hannah Earnshaw, Timothee Greffe, Roger Smith, Brian Grefenstette, Fiona Harrison, John Hennessy, Shouleh Nikzad, Charles Shapiro

Proceedings Volume 12191, 121910G (2022) https://doi.org/10.1117/12.2630367

KEYWORDS: Signal to noise ratio, High dynamic range imaging, Sensors, CMOS sensors, Point spread functions, Astronomy, High dynamic range image sensors, CMOS devices, Detection and tracking algorithms, Signal detection

Read Abstract +

SPIE Journal Paper | 22 April 2022

Characterization of low light performance of a complementary metal-oxide semiconductor sensor for ultraviolet astronomical applications

Timothee Greffe, Roger Smith, Myles Sherman, Fiona Harrison, Hannah Earnshaw, Brian Grefenstette, John Hennessy, Shouleh Nikzad

JATIS, Vol. 8, Issue 02, 026004, (April 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.2.026004

KEYWORDS: Sensors, Semiconductors, Cadmium sulfide, Ultraviolet radiation, Charge-coupled devices, CMOS sensors, Photons, Video, Astronomy, Switches

Read Abstract +

Complementary metal-oxide semiconductor (CMOS) detectors offer many advantages over charge-coupled devices (CCDs) for optical and ultraviolet (UV) astronomical applications, especially in space where high radiation tolerance is required. However, astronomical instruments are most often designed for low light-level observations demanding low dark current and read noise, good linearity, and high dynamic range, characteristics that have not been widely demonstrated for CMOS imagers. We report the performance, over temperatures from 140 to 240 K, of a radiation hardened SRI 4k × 2k back-side illuminated CMOS image sensor with surface treatments that make it highly sensitive in blue and UV bands. After suppressing emission from glow sites resulting from defects in the engineering grade device examined, a 0.077 me − / s dark current floor is reached at 160 K, rising to 1 me − / s at 184 K, rivaling that of the best CCDs. We examine the trade-off between readout speed and read noise, finding that 1.43 e − median read noise is achieved using line-wise digital correlated double sampling at 700 kpix / s / ch corresponding to a 1.5 s readout time. The 15 ke − well capacity in high gain mode extends to 120 ke − in dual gain mode. Continued collection of photogenerated charge during readout enables a further dynamic range extension beyond 106 e − effective well capacity with only 1% loss of exposure efficiency by combining short and long exposures. A quadratic fit to correct for non-linearity reduces gain correction residuals from 1.5% to 0.2% in low gain mode and to 0.4% in high gain mode. Cross-talk to adjacent pixels is only 0.4% vertically, 0.6% horizontally, and 0.1% diagonally. These characteristics plus the relatively large (10 μm) pixel size, quasi 4-side buttability, electronic shutter, and sub-array readout make this sensor an excellent choice for wide field astronomical imaging in space, even at far-UV wavelengths where sky background is very low.

SPIE Journal Paper | 22 February 2022 Open Access

Reconstruction of the NuSTAR point spread function using single-laser metrology

Hannah Earnshaw, Kristin Madsen, Karl Forster, Brian Grefenstette, Murray Brightman, Andreas Zoglauer, Fiona Harrison

JATIS, Vol. 8, Issue 01, 014009, (February 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.1.014009

KEYWORDS: Point spread functions, Laser metrology, Metrology, Transform theory, Telescopes, Sensors, Space operations, X-ray telescopes, Distortion, Time metrology

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 13 September 2018 Paper

Characterization of Redlen CZT detectors for hard x-ray astronomy

Sean Pike, Fiona Harrison, Jill Burnham, Walter Cook, Brian Grefenstette, Kristin Madsen, Hiromasa Miyasaka, Julian Sanders, Andrew Sosanya

Proceedings Volume 10762, 1076214 (2018) https://doi.org/10.1117/12.2321990

KEYWORDS: Sensors, Spectral resolution, Astronomy, X-ray astronomy, Americium, Crystals, Calibration, Hard x-rays, Cadmium, X-rays

Read Abstract +

Proceedings Article | 9 August 2018 Paper

Pushing the limits of NuSTAR detectors

Brian Grefenstette, W. Rick Cook, Fiona Harrison, Takao Kitaguchi, Kristin Madsen, Hiromasa Miyasaka, Sean Pike

Proceedings Volume 10709, 107092V (2018) https://doi.org/10.1117/12.2312844

KEYWORDS: Sensors, Calibration, Electronics, X-ray telescopes, X-ray optics, Hard x-rays, Signal to noise ratio, Space operations, Spectroscopes, Telescopes

Read Abstract +

Proceedings Article | 7 August 2018 Presentation + Paper

Characterization of Redlen CZT detectors for x-ray astronomy

Sean Pike, Fiona Harrison, Jill Burnham, Walter Cook, Brian Grefenstette, Kristin Madsen, Hiromasa Miyasaka

Proceedings Volume 10709, 107091D (2018) https://doi.org/10.1117/12.2313860

KEYWORDS: Sensors, X-ray astronomy, Americium, Spectral resolution, Crystals, X-ray detectors, Cadmium, X-ray telescopes, Zinc

Read Abstract +

Proceedings Article | 10 July 2018 Presentation

The high-energy x-ray probe (HEX-P) (Conference Presentation)

Fiona Harrison, Kristin Madsen, Brian Grefenstette, Daniel Stern, Ann Hornschemeier, Steven Boggs, Niel Brandt, Laura Brenneman, Deepto Chakrabarty, Finn Christensen, William Craig, Andrew Fabian, Martin Elvis, Jonathan Grindlay, Charles Hailey, Allan Hornstrup, Victoria Kaspi, Grzegorz Madejski, Giorgio Matt, Jon Miller, Hiromasa Miyasaka, Silvano Molendi, William Zhang, John Tomsick, Mihoko Yukita

Proceedings Volume 10699, 106992B (2018) https://doi.org/10.1117/12.2313836

KEYWORDS: X-rays, Spatial resolution, Active galactic nuclei, Binary data

Read Abstract +

Proceedings Article | 6 July 2018 Paper

Optical instrument design of the high-energy x-ray probe (HEX-P)

Kristin Madsen, Fiona Harrison, D. Broadway, F. Christensen, M. Descalle, D. Ferreira, B. Grefenstette, D. Gurgew, A. Hornschemeier, H. Miyasaka, T. Okajima, S. Pike, M. Pivovaroff, T. Saha, D. Stern, J. Vogel, D. Windt, W. Zhang

Proceedings Volume 10699, 106996M (2018) https://doi.org/10.1117/12.2314117

KEYWORDS: Coating, X-rays, Multilayers, Sensors, Mirrors, Photons, Platinum, Optical instrument design, Nickel, X-ray technology

Read Abstract +

Proceedings Article | 6 July 2018 Presentation + Paper

Effective area calibration of the nuclear spectroscopic telescope array (NuSTAR)

Kristin Madsen, Walter Cook, Karl Forster, Brian Grefenstette, Fiona Harrison, Hiromasa Miyasaka, Sean Pike

Proceedings Volume 10699, 106991W (2018) https://doi.org/10.1117/12.2313675

KEYWORDS: Calibration, Sensors, Absorption, Data modeling, Spectroscopy, Telescopes, X-rays, Platinum, Mirrors

Read Abstract +

SPIE Journal Paper | 27 October 2017 Open Access

Observational artifacts of Nuclear Spectroscopic Telescope Array: ghost rays and stray light

Kristin K. Madsen, Finn E. Christensen, William W. Craig, Karl W. Forster, Brian W. Grefenstette, Fiona A. Harrison, Hiromasa Miyasaka, Vikram Rana

JATIS, Vol. 3, Issue 04, 044003, (October 2017) https://doi.org/10.1117/12.10.1117/1.JATIS.3.4.044003

KEYWORDS: Photons, Sensors, Mirrors, Telescopes, Space telescopes, Reflection, Stray light, Spectroscopes, X-rays, Reflectivity

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 29 August 2017 Paper

Ground calibration of the spatial response and quantum efficiency of the CdZnTe hard x-ray detectors for NuSTAR

Brian Grefenstette, Varun Bhalerao, W. Rick Cook, Fiona Harrison, Takao Kitaguchi, Kristin Madsen, Peter Mao, Hiromasa Miyasaka, Vikram Rana

Proceedings Volume 10392, 1039207 (2017) https://doi.org/10.1117/12.2271365

KEYWORDS: Sensors, Calibration, Hard x-rays, Spectroscopy, Telescopes, Astrophysics

Read Abstract +

Proceedings Article | 15 July 2016 Paper

Getting NuSTAR on target: predicting mast motion

Karl Forster, Kristin Madsen, Hiromasa Miyasaka, William Craig, Fiona Harrison, Vikram Rana, Craig Markwardt, Brian Grefenstette

Proceedings Volume 9910, 99100Z (2016) https://doi.org/10.1117/12.2231239

KEYWORDS: Observatories, Space telescopes, Space operations, X-ray telescopes, Telescopes, Sensors, Cryogenics, Stars, Electrophoretic light scattering, Neodymium

Read Abstract +

Proceedings Article | 6 August 2014 Paper

NuSTAR observatory science operations: on-orbit acclimation

Karl Forster, Fiona Harrison, Suzanne Dodd, Daniel Stern, Hiromasa Miyasaka, Kristin Madsen, Brian Grefenstette, Craig Markwardt, William Craig, Francis Marshall

Proceedings Volume 9149, 91490R (2014) https://doi.org/10.1117/12.2056916

KEYWORDS: Space operations, Observatories, Sensors, System on a chip, Space telescopes, Calibration, Telescopes, Sun, X-ray telescopes, Stars

Read Abstract +

Proceedings Article | 24 July 2014 Paper

Inflight performance and calibration of the NuSTAR CdZnTe pixel detectors

Takao Kitaguchi, Varun Bhalerao, W. Cook, Karl Forster, Brian Grefenstette, Fiona Harrison, Kristin Madsen, Peter Mao, Hiromasa Miyasaka, Vikram Rana

Proceedings Volume 9144, 91441R (2014) https://doi.org/10.1117/12.2057342

KEYWORDS: Sensors, X-rays, Calibration, X-ray detectors, X-ray telescopes, Calcium, Astronomy, Signal detection, Space telescopes, Spectral models

Read Abstract +

Proceedings Article | 24 July 2014 Paper

The nuclear spectroscopic telescope array (NuSTAR) high-energy X-ray mission

Kristin Madsen, Fiona Harrison, Hongjun An, Steven Boggs, Finn Christensen, Rick Cook, William Craig, Karl Forster, Felix Fuerst, Brian Grefenstette, Charles Hailey, Takao Kitaguchi, Craig Markwardt, Peter Mao, Hiromasa Miyasaka, Vikram Rana, Daniel Stern, William Zhang, Andreas Zoglauer, Dominic Walton, Niels Westergaard

Proceedings Volume 9144, 91441P (2014) https://doi.org/10.1117/12.2056643

KEYWORDS: X-rays, Stars, X-ray telescopes, Space telescopes, Iron, Data modeling, Calibration, Galactic astronomy, Electroluminescent displays, Magnetism

Read Abstract +

Proceedings Article | 17 September 2012 Paper

Polarization studies with NuSTAR

Simone Lotti, Lorenzo Natalucci, Paolo Giommi, B. Grefenstette, Fiona Harrison, Kristin Madsen, Matteo Perri, Simonetta Puccetti, A. Zoglauer

Proceedings Volume 8443, 84434X (2012) https://doi.org/10.1117/12.925989

KEYWORDS: Polarization, Sensors, Photons, Compton scattering, Signal detection, Hard x-rays, Modulation, Optical simulations, Polarimetry, Absorption

Read Abstract +

Proceedings Article | 14 September 2011 Paper

Spectral calibration and modeling of the NuSTAR CdZnTe pixel detectors

Takao Kitaguchi, Brian Grefenstette, Fiona Harrison, Hiromasa Miyasaka, Varun Bhalerao, Walter Cook, Peter Mao, Vikram Rana, Steven Boggs, Andreas Zoglauer

Proceedings Volume 8145, 814507 (2011) https://doi.org/10.1117/12.896972

KEYWORDS: Sensors, Monte Carlo methods, Data modeling, Calibration, Spectral models, Space telescopes, Hard x-rays, Crystals, Clouds, X-ray telescopes

Read Abstract +

Proceedings Article | 29 July 2010 Paper

The Nuclear Spectroscopic Telescope Array (NuSTAR)

Fiona Harrison, Steve Boggs, Finn Christensen, William Craig, Charles Hailey, Daniel Stern, William Zhang, Lorella Angelini, Hongjun An, Varun Bhalerao, Nicolai Brejnholt, Lynn Cominsky, W. Rick Cook, Melania Doll, Paolo Giommi, Brian Grefenstette, Allan Hornstrup, Vicky Kaspi, Yunjin Kim, Takeo Kitaguchi, Jason Koglin, Carl Christian Liebe, Greg Madejski, Kristin Kruse Madsen, Peter Mao, David Meier, Hiromasa Miyasaka, Kaya Mori, Matteo Perri, Michael Pivovaroff, Simonetta Puccetti, Vikram Rana, Andreas Zoglauer

Proceedings Volume 7732, 77320S (2010) https://doi.org/10.1117/12.858065

KEYWORDS: Sensors, Space telescopes, Telescopes, X-ray telescopes, Multilayers, Spectroscopy, Hard x-rays, Spectral resolution, Optical alignment, Space operations

Read Abstract +

Showing 5 of 26 publications

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years