74 results on '"Corey J. Cochrane"'
Search Results
2. Characterization of Icy Moon Hydrospheres Through Joint Inversion of Gravity and Magnetic Field Measurements
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Flavio Petricca, Antonio Genova, Julie C. Castillo‐Rogez, Marshall J. Styczinski, Corey J. Cochrane, and Steven D. Vance
- Subjects
interior structure ,icy moons ,gravity field ,magnetic induction ,joint inversion ,hydrosphere ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Several bodies in the outer solar system are believed to host liquid water oceans underneath their icy surfaces. Knowledge of the hydrosphere properties is essential for understanding and assessing their habitability. We introduce a methodology based on Bayesian inference that enables a robust characterization of the hydrosphere through the combination of gravity and magnetic induction data. The interior models retrieved are consistent with the geophysical observations, leading to probability distributions for the relevant interior properties. We apply this joint inversion approach to constrain Europa's hydrosphere with gravity and magnetic field measurements acquired by the Galileo mission. Our results indicate that the combination of these datasets allows simultaneous constraints on the ice shell and ocean thickness, enhancing our knowledge of the hydrosphere structure. This methodology is valuable for synergistic interior science investigations of several missions in development or in planning, including Europa Clipper, JUICE and the Uranus Orbiter and Probe.
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- 2023
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3. Revealing the Interior Structure of Icy Moons with a Bayesian Approach to Magnetic Induction Measurements
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John B. Biersteker, Benjamin P. Weiss, Corey J. Cochrane, Camilla D. K. Harris, Xianzhe Jia, Krishan K. Khurana, Jiang Liu, Neil Murphy, and Carol A. Raymond
- Subjects
Europa ,Galilean satellites ,Magnetic fields ,Planetary interior ,Markov chain Monte Carlo ,Astronomy ,QB1-991 - Abstract
Some icy moons and small bodies in the solar system are believed to host subsurface liquid water oceans. The interaction of these saline, electrically conductive oceans with time-varying external magnetic fields generates induced magnetic fields. Magnetometry observations of these induced fields in turn enable the detection and characterization of these oceans. We present a framework for characterizing the interiors of icy moons using multifrequency induction and Bayesian inference applied to magnetometry measurements anticipated from the upcoming Europa Clipper mission. Using simulated data from the Europa Clipper Magnetometer, our approach can accurately retrieve a wide range of plausible internal structures for Europa. In particular, the ocean conductivity is recovered to within ±50% for all internal structure scenarios considered, and the ocean thickness can be retrieved to within ±25 km for five out of seven scenarios. Characterization of the ice shell thickness to ±50% is possible for six of seven scenarios. Our recovery of the ice shell thickness is highly contingent on accurate modeling of magnetic fields arising from the interaction of Europa with the ambient magnetospheric plasma, while the ocean thickness is more modestly affected and the ocean conductivity retrieval is largely unchanged. Furthermore, we find that the addition of a priori constraints (e.g., static gravity measurements) can yield improved ocean characterization compared to magnetometry alone, suggesting that multi-instrument techniques can play a key role in revealing the interiors of Europa and other ocean worlds.
- Published
- 2023
- Full Text
- View/download PDF
4. A CO2 Cycle on Ariel? Radiolytic Production and Migration to Low-latitude Cold Traps
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Richard J. Cartwright, Tom A. Nordheim, Riley A. DeColibus, William M. Grundy, Bryan J. Holler, Chloe B. Beddingfield, Michael M. Sori, Michael P. Lucas, Catherine M. Elder, Leonardo H. Regoli, Dale P. Cruikshank, Joshua P. Emery, Erin J. Leonard, and Corey J. Cochrane
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Uranian satellites ,Planetary surfaces ,Surface composition ,Surface processes ,Surface ices ,Astronomy ,QB1-991 - Abstract
CO _2 ice is present on the trailing hemisphere of Ariel but is mostly absent from its leading hemisphere. The leading/trailing hemispherical asymmetry in the distribution of CO _2 ice is consistent with radiolytic production of CO _2 , formed by charged particle bombardment of H _2 O ice and carbonaceous material in Ariel’s regolith. This longitudinal distribution of CO _2 on Ariel was previously characterized using 13 near-infrared reflectance spectra collected at “low” sub-observer latitudes between 30°S and 30°N. Here we investigated the distribution of CO _2 ice on Ariel using 18 new spectra: 2 collected over low sub-observer latitudes, 5 collected at “mid” sub-observer latitudes (31°N–44°N), and 11 collected over “high” sub-observer latitudes (45°N–51°N). Analysis of these data indicates that CO _2 ice is primarily concentrated on Ariel’s trailing hemisphere. However, CO _2 ice band strengths are diminished in the spectra collected over mid and high sub-observer latitudes. This sub-observer latitudinal trend may result from radiolytic production of CO _2 molecules at high latitudes and subsequent migration of this constituent to low-latitude cold traps. We detected a subtle feature near 2.13 μ m in two spectra collected over high sub-observer latitudes, which might result from a “forbidden” transition mode of CO _2 ice that is substantially stronger in well-mixed substrates composed of CO _2 and H _2 O ice, consistent with regolith-mixed CO _2 ice grains formed by radiolysis. Additionally, we detected a 2.35 μ m feature in some low sub-observer latitude spectra, which might result from CO formed as part of a CO _2 radiolytic production cycle.
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- 2022
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5. Visualizing Spacecraft Magnetic Fields on the Web and in VR.
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Benjamin Nuernberger, Corey J. Cochrane, Justin Williams, Lyle Klyne, Andreas Gottscholl, Hannes Kraus, Angelo Ryan Soriano, Pablo S. Narvaez, Chi-Chien Nelson Huang, Katherine Dang, Edward C. Gonzales, Neil Murphy, and Carol A. Raymond
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- 2023
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6. Exploring the Interior of Europa with the Europa Clipper
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James H. Roberts, William B. McKinnon, Catherine M. Elder, Gabriel Tobie, John B. Biersteker, Duncan Young, Ryan S. Park, Gregor Steinbrügge, Francis Nimmo, Samuel M. Howell, Julie C. Castillo-Rogez, Morgan L. Cable, Jacob N. Abrahams, Michael T. Bland, Chase Chivers, Corey J. Cochrane, Andrew J. Dombard, Carolyn Ernst, Antonio Genova, Christopher Gerekos, Christopher Glein, Camilla D. Harris, Hamish C. F. C. Hay, Paul O. Hayne, Matthew Hedman, Hauke Hussmann, Xianzhe Jia, Krishan Khurana, Walter S. Kiefer, Randolph Kirk, Margaret Kivelson, Justin Lawrence, Erin J. Leonard, Jonathan I. Lunine, Erwan Mazarico, Thomas B. McCord, Alfred McEwen, Carol Paty, Lynnae C. Quick, Carol A. Raymond, Kurt D. Retherford, Lorenz Roth, Abigail Rymer, Joachim Saur, Kirk Scanlan, Dustin M. Schroeder, David A. Senske, Wencheng Shao, Krista Soderlund, Elizabeth Spiers, Marshall J. Styczinski, Paolo Tortora, Steven D. Vance, Michaela N. Villarreal, Benjamin P. Weiss, Joseph H. Westlake, Paul Withers, Natalie Wolfenbarger, Bonnie Buratti, Haje Korth, and Robert T. Pappalardo
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- 2023
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7. Magnetic Field Modeling and Visualization of the Europa Clipper Spacecraft
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Corey J. Cochrane, Neil Murphy, Carol A. Raymond, John B. Biersteker, Katherine Dang, Xianzhe Jia, Haje Korth, Pablo Narvaez, Jodie B. Ream, and Benjamin P. Weiss
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- 2023
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8. The Psyche Magnetometry Investigation
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Benjamin P. Weiss, José M. G. Merayo, Jodie B. Ream, Rona Oran, Peter Brauer, Corey J. Cochrane, Kyle Cloutier, Linda T. Elkins-Tanton, John L. Jørgensen, Clara Maurel, Ryan S. Park, Carol A. Polanskey, Maria de Soria Santacruz-Pich, Carol A. Raymond, Christopher T. Russell, Daniel Wenkert, Mark A. Wieczorek, and Maria T. Zuber
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- 2023
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9. Submillimeter Wave Differential Absorption Radar for Water Vapor Sounding in the Martial Atmosphere.
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Omkar Pradhan, Kenneth B. Cooper, Leslie Tampari, Brian Drouin, Raquel Rodriguez Monje, Richard J. Roy, Jose V. Siles, and Corey J. Cochrane
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- 2020
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10. An FPGA-Based Signal Processor for FMCW Doppler Radar and Spectroscopy.
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Corey J. Cochrane, Kenneth B. Cooper, Stephen L. Durden, Raquel Rodriguez Monje, and Robert J. Dengler
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- 2020
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11. Neptune Odyssey: A Flagship Concept for the Exploration of the Neptune–Triton System
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Abigail M. Rymer, Kirby D. Runyon, Brenda A Clyde, Jorge I. Núñez, Romina Nikoukar, Krista M. Soderlund, Kunio Sayanagi, Mark Hofstadter, Lynnae C. Quick, S. Alan Stern, Tracy Becker, Matthew Hedman, Ian Cohen, Frank Crary, Jonathan J. Fortney, Janet Vertesi, Candy Hansen, Imke de Pater, Carol S Paty, Thomas Spilker, Tom Stallard, George B. Hospodarsky, H. Todd Smith, Hannah Wakeford, Sarah E. Moran, Andrew Annex, Paul Schenk, Martin Ozimek, Juan Arrieta, Ralph L. McNutt, Jr, Adam Masters, Amy A. Simon, Susan L Ensor, Clint T. Apland, Jonathan Bruzzi, Donald Alex Patthoff, Christopher Scott, Darien Christian Esquivel Del Campo, Christopher John Krupiarz, Corey J Cochrane, Curt Gantz, Daniel Rodriguez, Daniel Patrick Gallagher, Dana Meredith Hurley, Doug Crowley, Elizabeth Abel, Elena Provornikova, Elizabeth P Turtle, George Clark, Jacob Wilkes, Jack Hunt, James H. Roberts, Jeremy Rehm, Kelvin Murray, Larry Wolfarth, Leigh N. Fletcher, Linda Spilker, Emily S. Martin, Marzia Parisi, Mike Norkus, Noam Izenberg, Robert Stough, Ron J. Vervack, Jr, Kathleen Mandt, Kevin B. Stevenson, Seth Kijewski, Weilun Cheng, Jay D Feldman, Gary Allen, Dinesh Prabhu, Soumya Dutta, Cindy Young, and Joseph Williams
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Lunar And Planetary Science And Exploration - Abstract
The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Neptune–Triton system. This bold mission of exploration would orbit an ice-giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon Triton. Triton is a captured dwarf planet from the Kuiper Belt, twin of Pluto, and likely ocean world. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraft—in a class equivalent to the NASA/ESA/ASI Cassini spacecraft—would launch by 2031 on a Space Launch System or equivalent launch vehicle and utilize a Jupiter gravity assist for a 12 yr cruise to Neptune and a 4 yr prime orbital mission; alternatively a launch after 2031 would have a 16 yr direct-to-Neptune cruise phase. Our solution provides annual launch opportunities and allows for an easy upgrade to the shorter (12 yr) cruise. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), using the moonʼs gravity to shape the orbital tour and allow coverage of Triton, Neptune, and the space environment. The atmospheric entry probe would descend in ∼37 minutes to the 10 bar pressure level in Neptune’s atmosphere just before Odysseyʼs orbit-insertion engine burn. Odysseyʼs mission would end by conducting a Cassini-like “Grand Finale,” passing inside the rings and ultimately taking a final great plunge into Neptuneʼs atmosphere.
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- 2021
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12. Unsupervised detection of Saturn magnetic field boundary crossings from plasma spectrometer data.
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Ameya Daigavane, Kiri L. Wagstaff, Gary Doran, Corey J. Cochrane, Caitriona M. Jackman, and Abigail Rymer
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- 2022
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13. Using FMCW Doppler Radar to Detect Targets up to the Maximum Unambiguous Range.
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Kenneth B. Cooper, Stephen L. Durden, Corey J. Cochrane, Raquel Rodriguez Monje, Robert J. Dengler, and Chad Baldi
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- 2017
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14. The Magnetometer on the Psyche mission
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Jose M. G. Merayo, Benjamin P. Weiss, Jodie Ream, Rona Oran, Peter Brauer, Corey J. Cochrane, Kyle D. Cloutier, Lindy Elkins-Tanton, John Leif Jørgensen, Clara Maurel, Ryan S. Park, Carol A. Polanskey, Maria De Soria-Santacruz Pich, Carol A. Raymond, Christopher Russell, Daniel Wenkert, Mark A. Wieczorek, Maria T. Zuber, and Kyle Webster
- Abstract
The asteroid (16) Psyche is the target of the NASA Psyche mission, where the magnetometer is one of the three science instruments on board. Its purpose is to prove whether the asteroid formed from the core of a differentiated planetesimal. The magnetometer will measure the magnetic field at different distances from the asteroid in order to detect any remanent magnetization, where a magnetic moment larger than 2×10^14 Am2 could imply that the body once generated a core dynamo, and therefore formed as an igneous differentiation.The Psyche spacecraft carries two three-axis fluxgate magnetometers mounted on a fixed boom at 2.15m and 1.45m, respectively, which provide redundancy and gradiometer capabilities to compensate for spacecraft-generated magnetic fields. The magnetometers will be powered on early in the initial checkout phase and remain on throughout cruise and orbital operations and producing 50 vectors per second. The in-flight temperature of the magnetometers is expected to span a large range, therefore an extensive calibration program has been carried out in order to characterize the instruments and prove the performance pre-flight.
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- 2023
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15. Band diagram for low-k/Cu interconnects: The starting point for understanding back-end-of-line (BEOL) electrical reliability.
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Michael J. Mutch, Thomas Pomorski, Brad C. Bittel, Corey J. Cochrane, Patrick M. Lenahan, Xin Liu, Robert J. Nemanich, Justin Brockman, Marc French, Markus Kuhn, Benjamin French, and Sean W. King
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- 2016
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16. A Fast Classification Scheme in Raman Spectroscopy for the Identification of Mineral Mixtures Using a Large Database With Correlated Predictors.
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Corey J. Cochrane and Jordana Blacksberg
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- 2015
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17. Miniature high-speed, low-pulse-energy picosecond Raman spectrometer for identification of minerals and organics in planetary science
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Jordana Blacksberg, Erik Alerstam, Corey J. Cochrane, Yuki Maruyama, and Jack D. Farmer
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- 2020
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18. A Compact, Low Power Consumption, and Highly Sensitive 95 GHz Doppler Radar
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Ken B. Cooper, Maria Alonso-delPino, Omkar Pradhan, Adrian Tang, Raquel Monje, Corey J. Cochrane, Tristan Ossama El Bouayadi, and Robert J. Dengler
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Signal processing ,Computer science ,business.industry ,Amplifier ,010401 analytical chemistry ,Doppler radar ,Electrical engineering ,Transmitter power output ,01 natural sciences ,0104 chemical sciences ,law.invention ,CMOS ,law ,Waveform ,Electrical and Electronic Engineering ,Antenna (radio) ,Radar ,business ,Instrumentation - Abstract
We report on the architecture and performance of a highly sensitive 95 GHz Doppler radar instrument with 0.6Watt transmit power designed for low power consumption and small size. The radar’s sensitivity is validated using a calibration target, and its remote sensing capabilities are demonstrated through the detection of clouds, rain, insects, and distant vehicles. The radar uses a frequency-modulated continuous-wave (FMCW) waveform, a single antenna with ultra-high-isolation quasioptical transmit/receive duplexing, an InP low-noise amplifier for receiving, and a GaN power amplifier for transmitting. A DC power consumption of 22 W for the RF and digital subsystems is achieved, in part, by a combination of a power-efficient waveform generation/detection and signal processing board and a CMOS-based system-on-chip W-band oscillator. Excluding power supplies and a computer interface, the radar system mass is under 6 kg, making it attractive for future deployment from platforms with constrained accommodation resources.
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- 2020
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19. Revealing the interior structure of icy moons with a Bayesian approach to magnetic induction measurements
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John B. Biersteker, Benjamin P. Weiss, Corey J. Cochrane, Camilla D. K. Harris, Xianzhe Jia, Krishan K. Khurana, Jiang Liu, Neil Murphy, and Carol A. Raymond
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Earth and Planetary Astrophysics (astro-ph.EP) ,Geophysics ,Physics - Space Physics ,Space and Planetary Science ,Earth and Planetary Sciences (miscellaneous) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Space Physics (physics.space-ph) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Some icy moons and small bodies in the solar system are believed to host subsurface liquid water oceans. The interaction of these saline, electrically conductive oceans with time-varying external magnetic fields generates induced magnetic fields. Magnetometry observations of these induced fields in turn enable the detection and characterization of these oceans. We present a framework for characterizing the interiors of icy moons using multi-frequency induction and Bayesian inference applied to magnetometry measurements anticipated from the upcoming Europa Clipper mission. Using simulated data from the Europa Clipper Magnetometer (ECM), our approach can accurately retrieve a wide range of plausible internal structures for Europa. In particular, the ocean conductivity is recovered to within ${\pm}50\%$ for all internal structure scenarios considered and the ocean thickness can be retrieved to within ${\pm}25~\mathrm{km}$ for five out of seven scenarios. Characterization of the ice shell thickness to ${\pm}50\%$ is possible for six of seven scenarios. Our recovery of the ice shell thickness is highly contingent on accurate modeling of magnetic fields arising from the interaction of Europa with the ambient magnetospheric plasma, while the ocean thickness is more modestly affected and the ocean conductivity retrieval is largely unchanged. Furthermore, we find that the addition of a priori constraints (e.g., static gravity measurements) can yield improved ocean characterization compared to magnetometry alone, suggesting that multi-instrument techniques can play a key role in revealing the interiors of Europa and other ocean worlds., Comment: 18 pages, 16 figures, submitted to Planetary Science Journal
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- 2022
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20. In search of subsurface oceans within the Uranian moons
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Corey J. Cochrane, Steven D. Vance, M. J. Styczinski, Leonardo Regoli, Adam Masters, Tom Nordheim, and The Royal Society
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Geochemistry & Geophysics ,Solar System ,Ariel ,Umbriel ,Magnetometer ,Miranda ,Uranus ,MODELS ,FOS: Physical sciences ,MAGNETIC-FIELDS ,EUROPA ,Astrobiology ,law.invention ,Physics::Geophysics ,Jupiter ,Physics - Geophysics ,ocean worlds ,Exploration of Jupiter ,Physics - Space Physics ,Geochemistry and Petrology ,Neptune ,law ,0201 Astronomical and Space Sciences ,Earth and Planetary Sciences (miscellaneous) ,WATER ,0402 Geochemistry ,CALLISTO ,Earth and Planetary Astrophysics (astro-ph.EP) ,Science & Technology ,ORIGIN ,CONSTRAINTS ,Moons of Uranus ,Space Physics (physics.space-ph) ,Geophysics (physics.geo-ph) ,Geophysics ,0403 Geology ,Space and Planetary Science ,magnetic induction ,Physics::Space Physics ,Physical Sciences ,Astrophysics::Earth and Planetary Astrophysics ,Geology ,Ice giant ,SYSTEM ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Galileo mission to Jupiter discovered magnetic signatures associated with hidden sub-surface oceans at the moons Europa and Callisto using the phenomenon of magnetic induction. These induced magnetic fields originate from electrically conductive layers within the moons and are driven by Jupiter’s strong time-varying magnetic field. The ice giants and their moons are also ideal laboratories for magnetic induction studies. Both Uranus and Neptune have a strongly tilted magnetic axis with respect to their spin axis, creating a dynamic and strongly variable magnetic field environment at the orbits of their major moons. Although Voyager-2 visited the ice giants in the 1980s, it did not pass close enough to any of the moons to detect magnetic induction signatures. However, Voyager-2 revealed that some of these moons exhibit surface features that hint at recent geologically activity, possibly associated with sub-surface oceans. Future missions to the ice giants may therefore be capable of discovering sub-surface oceans, thereby adding to the family of known “ocean worlds” in our solar system. Here, we assess magnetic induction as a technique for investigating sub-surface oceans within the major moons of Uranus. Furthermore, we establish the ability to distinguish induction responses created by different interior characteristics that tie into the induction response: ocean thickness, conductivity, and depth, and ionospheric conductance. The results reported here demonstrate the possibility of single-pass ocean detection and constrained characterization within the moons of Miranda, Ariel, and Umbriel, and provide guidance for magnetometer selection and trajectory design for future missions to Uranus.
- Published
- 2021
21. Triton’s Variable Interaction With Neptune’s Magnetospheric Plasma
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Carol Paty, Lucas Liuzzo, Mats Holmström, Julie Castillo-Rogez, Tom Nordheim, Sven Simon, Adrienn Luspay-Kuti, Steven D. Vance, Andrew R. Poppe, Kathleen Mandt, Corey J. Cochrane, Louise M. Prockter, Karl L. Mitchell, and Peter Addison
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Physics ,Variable (computer science) ,Geophysics ,Magnetospheric plasma ,Space and Planetary Science ,Neptune ,Astrophysics ,Ice giant - Published
- 2021
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22. Neptune and Triton: A Flagship for Everyone
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Kirby Runyon, Tom Stallard, Kenneth C. Hansen, Tom Spilker, Hannah R. Wakeford, Alan Stern, Parisi Marzia, Kevin B. Stevenson, Ronald J. Vervack, Corey J. Cochrane, Jonathan J. Fortney, Juan Arrieta, George Hospodarsky, Jorge I. Nunez, Abby Azari, Kathleen Mandt, Frank Crary, Dana M. Hurley, Alex Patthoff, Ian J. Cohen, Kunio M. Sayanagi, Elena Provornikova, Adam Masters, Ralph L. McNutt, Lynne Quick, Matthew M. Hedman, H. Todd Smith, James Roberts, Sarah E. Moran, Amy Simon, Paul M. Schenk, Elizabeth P. Turtle, Tracy M. Becker, Emily S. Martin, Mark Hofstadter, Leigh N. Fletcher, R. Nikoukar, Linda Spilker, Imke de Pater, Noam R. Izenberg, Carol Paty, Janet Vertisi, C. J. Hansen, A. M. Annex, Krista M. Soderlund, and Abigail Rymer
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Neptune ,media_common.quotation_subject ,Art ,media_common ,Astrobiology - Published
- 2021
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23. New Frontiers-class Uranus Orbiter: Exploring the feasibility of achieving multidisciplinary science with a mid-scale mission
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Kate Craft, Roland M. B. Young, Paolo Tortora, Ravit Helled, Jonathan J. Fortney, Robert Ebert, Wes Patterson, S. Luszcz-Cook, Alice Lucchetti, Carol Paty, C. M. Jackman, Alessandro Mura, Alan Stern, Alice Cocoros, Ian J. Cohen, Chloe B. Beddingfield, Katrin Stephan, Jesper Gjerloev, Lynnae C. Quick, Catherine Elder, Robert A. Dillman, Drew Turner, Peter Wurz, Matina Gkioulidou, Shawn Brueshaber, Chris Paranicas, Kunio M. Sayanagi, Sasha Ukhorskiy, Sarah E. Moran, R. Nikoukar, Kirby Runyon, Michael H. Wong, Todd Smith, Carolyn M. Ernst, Maurizio Pajola, Matthew M. Hedman, Gianrico Filacchione, Yasumasa Kasaba, Marzia Parisi, Leigh N. Fletcher, Chuanfei Dong, Caitlin Ahrens, Gina A. DiBraccio, Shawn Brooks, Robert Chancia, Michael P. Lucas, Leonardo Regoli, Imke de Pater, Alena Probst, Peter Kollmann, Athena Coustenis, James H. Roberts, Daniel J. Gershman, Lauren Jozwiak, Soumyo Dutta, Linda Spilker, Elizabeth P. Turtle, Sebastien Rodriguez, Yongliang Zhang, Gangkai Poh, George Clark, Tibor S. Balint, Ingrid Daubar, Kathleen Mandt, Adam Masters, Richard Holme, Devanshu Jha, Go Murakami, Noemi Pinilla-Alonso, Sarah K. Vines, Olivier Mousis, Krista M. Soderlund, Athul Pradeepkumar Girija, Ronald J. Vervack, Corey J. Cochrane, Xin Cao, Emma J. Bunce, Shannon MacKenzie, George Hospodarsky, Sébastien Charnoz, Elena Adams, Kimberly Moore, Erin Leonard, Heather Meyer, Rebecca A. Harbison, Abigail Rymer, Sabine Stanley, Barry Mauk, and Richard Cartwright
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Class (computer programming) ,Orbiter ,Scale (ratio) ,Multidisciplinary approach ,Computer science ,law ,Systems engineering ,Uranus ,law.invention - Published
- 2021
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24. Submillimeter Wave Differential Absorption Radar for Water Vapor Sounding in the Martial Atmosphere
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Ken B. Cooper, Corey J. Cochrane, Richard Roy, Leslie Tampari, Omkar Pradhan, Jose V. Siles, Brian J. Drouin, and Raquel Monje
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010504 meteorology & atmospheric sciences ,Mars Exploration Program ,01 natural sciences ,law.invention ,Depth sounding ,Surface wave ,law ,Martian surface ,Continuous wave ,Environmental science ,Radar ,Absorption (electromagnetic radiation) ,Water vapor ,0105 earth and related environmental sciences ,Remote sensing - Abstract
In this study we report on the current state-of-progress of the Water Sounding Short-range Radar (WASSR) project. The proposed WASSR instrument will facilitate estimation of near-surface water vapor profile on Mars. This project is supported under NASA's Maturation of Instruments for Solar System Exploration (MatISSE) program and is a frequency modulated continuous wave (FMCW) differential absorption radar (DAR) instrument. The scope of the work presented here includes a discussion of (i) the science background and motivation for profiling water vapor near the Martian surface, (ii) the differential absorption radar (DAR) technique implemented at the 557 GHz water vapor absorption line, and (iii) the submillimeter wave radar system implementation and characterization.
- Published
- 2020
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25. An improved adaptive signal averaging technique for noise reduction and tracking enhancements in continuous wave magnetic resonance
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Brian R. Manning, Corey J. Cochrane, and Patrick M. Lenahan
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010302 applied physics ,Physics ,medicine.diagnostic_test ,Electrically detected magnetic resonance ,Noise reduction ,Magnetic resonance imaging ,Tracking (particle physics) ,01 natural sciences ,010305 fluids & plasmas ,law.invention ,Computational physics ,law ,0103 physical sciences ,medicine ,Continuous wave ,Signal averaging ,Electron paramagnetic resonance ,Instrumentation ,Numerical stability - Abstract
We have significantly refined an adaptive signal averaging approach developed primarily for continuous wave electron paramagnetic resonance and electrically detected magnetic resonance measurements. This refinement overcomes several limitations and greatly simplifies the earlier approach. The new technique provides a large improvement in tracking and numerical stability and also features fewer adjustable parameters making this approach more user intuitive.
- Published
- 2020
26. Magnetic Induction in Convecting Galilean Oceans
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Natalia Gómez-Pérez, Carol Paty, Steven D. Vance, M. J. Styczinski, Corey J. Cochrane, Krista M. Soderlund, and Bruce G. Bills
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Physics ,Jupiter ,Amplitude response ,Phase (matter) ,Physics::Space Physics ,Astrophysics::Earth and Planetary Astrophysics ,Conductivity ,Icy moon ,Physics::Atmospheric and Oceanic Physics ,Physics::Geophysics ,Astrobiology ,Electromagnetic induction ,Galilean - Abstract
To date, analyses of magnetic induction in putative oceans in Jupiter's large icy moons have assumed uniform conductivity in the modeled oceans. However, the phase and amplitude response of the ind...
- Published
- 2020
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27. Magnetic Field Sensing with 4H SiC Diodes: N vs P Implantation
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Corey J. Cochrane, Hannes Kraus, Philip G. Neudeck, James P. Ashton, Ryan J. Waskiewicz, Patrick M. Lenahan, and David J. Spry
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010302 applied physics ,Materials science ,Electrically detected magnetic resonance ,Magnetoresistance ,business.industry ,Magnetometer ,Mechanical Engineering ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,law.invention ,Magnetic field ,Mechanics of Materials ,law ,0103 physical sciences ,Optoelectronics ,General Materials Science ,0210 nano-technology ,business ,Diode - Abstract
We explore the magnetic sensing capabilities of two 4H-SiC n+p diodes fabricated by NASA Glenn which only differ in the implanted ion species, nitrogen and phosphorus, and the implant activation annealing time. We use low-and high-field electrically detected magnetic resonance (EDMR) to investigate the defect structure used to sense magnetic fields as well as to evaluate the sensitivity. In addition, we expose these devices to high energy electron radiation to evaluate the defect sensing capability in a harsh radiation environment. The results from this work will allow us to tailor our processing methods to design a more optimal 4H-SiC pn diode for magnetic field sensing in harsh environments.
- Published
- 2018
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28. Using FMCW Doppler Radar to Detect Targets up to the Maximum Unambiguous Range
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Corey J. Cochrane, Chad Baldi, Ken B. Cooper, Stephen L. Durden, Raquel Monje, and Robert J. Dengler
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Pulse repetition frequency ,Radar cross-section ,Computer science ,Doppler radar ,Fire-control radar ,02 engineering and technology ,01 natural sciences ,law.invention ,symbols.namesake ,Radar engineering details ,law ,Radar imaging ,0202 electrical engineering, electronic engineering, information engineering ,Chirp ,Waveform ,Electrical and Electronic Engineering ,Radar ,Low-frequency radar ,Radar horizon ,Physics::Atmospheric and Oceanic Physics ,Remote sensing ,Low probability of intercept radar ,Radar tracker ,Pulse-Doppler radar ,010401 analytical chemistry ,020206 networking & telecommunications ,Geotechnical Engineering and Engineering Geology ,Radar lock-on ,0104 chemical sciences ,Continuous-wave radar ,Bistatic radar ,Man-portable radar ,Monopulse radar ,symbols ,3D radar ,Radar display ,Doppler effect - Abstract
Most applications of frequency-modulated continuous-wave radar described in the literature involve targets that are in relatively close proximity to the radar. In these cases, the round-trip travel time of the target’s radar signature is small relative to the transmit chirp duration, simplifying the processing required for range and velocity extraction. This is not the case for more distant targets, where much of the radar signature is received after the start of the subsequent transmit waveform. In this letter, we examine various signal-processing options for coping with this long-range condition. We analytically demonstrate how to retain both range and Doppler shift information for an arbitrary number of targets spaced anywhere from very near the target up to the radar’s unambiguous range. The motivation for this work is to develop a 95-GHz Doppler radar for measuring ice and dust particle dynamics in cometary jets. Simulations and experimental results are provided to validate our methods.
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- 2017
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29. UMaMI: A New Frontiers-style Mission Concept to Explore the Uranian System
- Author
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Corey J. Cochrane, Nathan Strange, Chloe B. Beddingfield, Matthew S. Tiscareno, D. Alex Patthoff, Shawn Brooks, Tom Nordheim, Tibor S. Balint, Richard Cartwright, Erin Leonard, and Catherine Elder
- Subjects
Cognitive science ,Geophysics ,Space and Planetary Science ,Earth and Planetary Sciences (miscellaneous) ,Astronomy and Astrophysics ,Umami ,Geology ,Style (sociolinguistics) - Abstract
With the public and scientific community’s growing interest in ocean worlds, the icy moons of Uranus offer an ideal opportunity to explore a native ice giant satellite system. Although it is uncertain whether any of the Uranian moons currently host subsurface oceans, there is tantalizing evidence—including geologically young surface features and volatiles that are not stable—that this could be the case, making these objects possible ocean worlds in their own right. Determining whether subsurface oceans are present in the interiors of these moons would increase our understanding of the conditions under which subsurface oceans are formed and maintained over the history of the solar system. The presence and stability of a subsurface ocean in the interiors of any icy body is key to identifying its potential as a habitable environment. In this work, we describe a midsize (New Frontiers class) mission concept: the Uranian Magnetosphere and Moons Investigator. The magnetosphere and moons are tightly coupled parts of the Uranian system, complementary to study, and best analyzed together in order to investigate the Uranian moons as potential ocean worlds. Additionally, this mission concept includes study of Uranus’s unique rings and magnetosphere–solar wind interaction. With a future, more detailed trade study, there also could be opportunities for studies of Uranus itself.
- Published
- 2021
- Full Text
- View/download PDF
30. Magnetic Field Sensing with Atomic Scale Defects in SiC Devices
- Author
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Mark A. Anders, Corey J. Cochrane, Patrick M. Lenahan, and Jordana Blacksberg
- Subjects
Materials science ,Magnetoresistance ,Band gap ,Magnetometer ,02 engineering and technology ,01 natural sciences ,Atomic units ,law.invention ,chemistry.chemical_compound ,law ,0103 physical sciences ,Silicon carbide ,Electronic engineering ,General Materials Science ,Electronics ,Spin (physics) ,010302 applied physics ,business.industry ,Mechanical Engineering ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Magnetic field ,chemistry ,Mechanics of Materials ,Optoelectronics ,0210 nano-technology ,business - Abstract
Silicon carbide (SiC) is well known by the semiconductor industry to have significant potential for electronics used in high temperature environments due to its wide bandgap. It is not so well-known, however, that SiC also has great potential in the area of magnetic field sensing. Using the recently demonstrated zero-field spin dependent recombination (SDR) phenomenon that naturally arises in SiC based devices, near-zero magnetic field measurements can be made with moderately high sensitivity.
- Published
- 2016
- Full Text
- View/download PDF
31. Long range-Doppler Demonstration of a 95 GHz FMCW Radar
- Author
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Ken B. Cooper, Stephen L. Durden, Mathieu Choukroun, Corey J. Cochrane, Adrian Tang, Robert J. Dengler, and Raquel Monje
- Subjects
Spectrometer ,020208 electrical & electronic engineering ,Doppler radar ,020206 networking & telecommunications ,02 engineering and technology ,law.invention ,Continuous-wave radar ,symbols.namesake ,law ,0202 electrical engineering, electronic engineering, information engineering ,symbols ,Chirp ,Continuous wave ,Astrophysics::Earth and Planetary Astrophysics ,Radar ,Antenna (radio) ,Doppler effect ,Physics::Atmospheric and Oceanic Physics ,Geology ,Remote sensing - Abstract
We present the first demonstration of a thermal-noise-limited 95 GHz frequency modulated continuous wave (FMCW) Doppler radar with high (1 Watt) transmit power and long-range Doppler detection capabilities. The 95 GHz radar is part of the GAISR (Gas And Ice Spectrometer/Radar) instrument to probe the dynamics and distribution of cometary jets and plumes in icy bodies in the solar system. Radar measurements were carried out using a variety of targets at different range and velocities, such as freeway cars, clouds, rain and hillsides, to test the range and Doppler capabilities. The compact design (a single 15 cm diameter primary antenna), and high quality data presented in this paper makes this 95 GHz FMCW radar uniquely suitable for future space missions for Planetary and Earth Science applications.
- Published
- 2018
- Full Text
- View/download PDF
32. A W-band comet-jet Doppler radar prototype
- Author
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Robert J. Dengler, Corey J. Cochrane, Ken B. Cooper, Stephen L. Durden, Maria Alonso-delPino, Mathieu Choukroun, Adrian Tang, and Raquel Monje
- Subjects
Pulse repetition frequency ,Physics ,Outer planets ,business.industry ,Comet ,Doppler radar ,0211 other engineering and technologies ,020206 networking & telecommunications ,02 engineering and technology ,law.invention ,Optics ,W band ,law ,0202 electrical engineering, electronic engineering, information engineering ,Chirp ,Astrophysics::Earth and Planetary Astrophysics ,Radio frequency ,Radar ,business ,021101 geological & geomatics engineering - Abstract
A 95 GHz Doppler radar prototype has been developed with a design guided by requirements for potential space flight missions to comets or icy moons of the outer planets in order to probe ice- and dust-filled jets and plumes. The radar operates in a frequency-modulated continuous-wave (FMCW) mode with a bandwidth, pulse repetition interval, and coherent integration time chosen to achieve better than 10 m range resolution, 0.1 m/s velocity resolution, 5.1 km maximum unambiguous range, and 46 m/s maximum unambiguous velocity span. With an ultra-high transmit/receive isolation exceeding 85 dB, the radar operates with thermal-noise-limited sensitivity even with 1 Watt of continuous transmit power and a 540 K noise-temperature receiver sharing a single, 15 cm diameter monostatic aperture. Experimental testing has verified the radar's range-Doppler remote sensing capabilities using a developing rain shower as a dynamic and distributed target.
- Published
- 2018
- Full Text
- View/download PDF
33. Relationship Between the 4H-SiC/SiO2 Interface Structure and Electronic Properties Explored by Electrically Detected Magnetic Resonance
- Author
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Mark A. Anders, Aivars J. Lelis, Patrick M. Lenahan, and Corey J. Cochrane
- Subjects
Materials science ,Electrically detected magnetic resonance ,Silicon ,Annealing (metallurgy) ,business.industry ,chemistry.chemical_element ,Electronic, Optical and Magnetic Materials ,law.invention ,Carbide ,chemistry.chemical_compound ,Nuclear magnetic resonance ,chemistry ,law ,MOSFET ,Silicon carbide ,Optoelectronics ,Electrical and Electronic Engineering ,business ,Electron paramagnetic resonance ,Electronic properties - Abstract
In this paper, an exceptionally sensitive form of electron paramagnetic resonance called electrically detected magnetic resonance (EDMR) is utilized to investigate performance limiting imperfections at and very near the interface of 4H-silicon carbide MOSFETs. EDMR measurements are made over an extremely wide range of frequencies, 16 GHz–350 MHz. Multiple interface/near interface defects are identified and strong evidence for significant disorder at the interface region is presented.
- Published
- 2015
- Full Text
- View/download PDF
34. High, Low, and Zero Field Spin Dependent Recombination in 4H SiC Metal Oxide Semiconductor Field Effect and Bipolar Junction Transistors
- Author
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Corey J. Cochrane, Patrick M. Lenahan, and Aivars J. Lelis
- Subjects
Materials science ,business.industry ,Transistor ,Field effect ,law.invention ,Metal ,Oxide semiconductor ,Zero field ,law ,visual_art ,visual_art.visual_art_medium ,Optoelectronics ,business ,Recombination ,Spin-½ - Abstract
Silicon carbide based transistors have great promise in high temperature and high power applications. In particular, the great promise of silicon carbide based metal oxide semiconductor field effect transistors (MOSFETs) has been somewhat limited by materials physics problems in the region near the silicon carbide-silicon dioxide interface. Materials physics problems in SiC bipolar junction transistors (BJTs) are also topics of current interest. Studies involving a combination of high, low, and zero field electrically detected magnetic resonance via spin dependent recombination provide a powerful approach for the understanding of SiC transistor materials physics problems. In this paper, we will review our group’s work on multi-field spin dependent recombination of 4H SiC based MOSFETs and BJTs. We emphasize the physical principles involved in the measurements in part because they could potentially be quite useful if they were to be applied to other wide band gap semiconductor device systems.
- Published
- 2014
- Full Text
- View/download PDF
35. Erratum: Vectorized magnetometer for space applications using electrical readout of atomic scale defects in silicon carbide
- Author
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Corey J, Cochrane, Jordana, Blacksberg, Mark A, Anders, and Patrick M, Lenahan
- Subjects
Multidisciplinary ,Article - Abstract
Magnetometers are essential for scientific investigation of planetary bodies and are therefore ubiquitous on missions in space. Fluxgate and optically pumped atomic gas based magnetometers are typically flown because of their proven performance, reliability, and ability to adhere to the strict requirements associated with space missions. However, their complexity, size, and cost prevent their applicability in smaller missions involving cubesats. Conventional solid-state based magnetometers pose a viable solution, though many are prone to radiation damage and plagued with temperature instabilities. In this work, we report on the development of a new self-calibrating, solid-state based magnetometer which measures magnetic field induced changes in current within a SiC pn junction caused by the interaction of external magnetic fields with the atomic scale defects intrinsic to the semiconductor. Unlike heritage designs, the magnetometer does not require inductive sensing elements, high frequency radio, and/or optical circuitry and can be made significantly more compact and lightweight, thus enabling missions leveraging swarms of cubesats capable of science returns not possible with a single large-scale satellite. Additionally, the robustness of the SiC semiconductor allows for operation in extreme conditions such as the hot Venusian surface and the high radiation environment of the Jovian system.
- Published
- 2017
- Full Text
- View/download PDF
36. A combination millimeter-wave Doppler radar and THz spectrometer for planetary science
- Author
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Chad Baldi, Simone Tanelli, Adrian Tang, Goutam Chattopadhyay, Raquel Monje, T.O. El Bouayadi, Robert J. Dengler, D. Gonzalez, Ken B. Cooper, Stephen L. Durden, Erio Gandini, Mathieu Choukroun, Anders Skalare, Corey J. Cochrane, and Nuria Llombart
- Subjects
Physics ,Spectrometer ,Pulse-Doppler radar ,business.industry ,010401 analytical chemistry ,Doppler radar ,020206 networking & telecommunications ,02 engineering and technology ,01 natural sciences ,0104 chemical sciences ,law.invention ,Continuous-wave radar ,Optics ,Radar engineering details ,Radar astronomy ,law ,Radar imaging ,0202 electrical engineering, electronic engineering, information engineering ,Radar ,business ,Physics::Atmospheric and Oceanic Physics ,Remote sensing - Abstract
A combination 95 GHz radar and 270/560 GHz spectrometer is being built as a space instrument prototype for probing plumes and jet phenomena in the solar system. Dubbed GAISR (Gas And Ice Spectrometer/Radar), the instrument's radar will make simultaneous range/Doppler measurements of 0.1–10 mm sized ice and dust particles out to a few km in range, while its tunable spectrometer will detect the abundance and velocities of gaseous water and other volatiles. Here we describe how the radar and spectrometer share a back-end architecture, and present some innovative elements of GAISR's frequency-modulated continuous-wave (FMCW) radar, including high-isolation and low-loss transmit/receive duplexing and a phase-noise-canceling RF architecture.
- Published
- 2016
- Full Text
- View/download PDF
37. Vectorized magnetometer for space applications using electrical readout of atomic scale defects in silicon carbide
- Author
-
Patrick M. Lenahan, Mark A. Anders, Corey J. Cochrane, and Jordana Blacksberg
- Subjects
010302 applied physics ,Physics ,Multidisciplinary ,business.industry ,Magnetometer ,02 engineering and technology ,021001 nanoscience & nanotechnology ,High frequency ,01 natural sciences ,Fluxgate compass ,Space exploration ,Magnetic field ,law.invention ,chemistry.chemical_compound ,Semiconductor ,chemistry ,law ,Robustness (computer science) ,0103 physical sciences ,Silicon carbide ,Aerospace engineering ,Erratum ,0210 nano-technology ,business - Abstract
Magnetometers are essential for scientific investigation of planetary bodies and are therefore ubiquitous on missions in space. Fluxgate and optically pumped atomic gas based magnetometers are typically flown because of their proven performance, reliability, and ability to adhere to the strict requirements associated with space missions. However, their complexity, size, and cost prevent their applicability in smaller missions involving cubesats. Conventional solid-state based magnetometers pose a viable solution, though many are prone to radiation damage and plagued with temperature instabilities. In this work, we report on the development of a new self-calibrating, solid-state based magnetometer which measures magnetic field induced changes in current within a SiC pn junction caused by the interaction of external magnetic fields with the atomic scale defects intrinsic to the semiconductor. Unlike heritage designs, the magnetometer does not require inductive sensing elements, high frequency radio, and/or optical circuitry and can be made significantly more compact and lightweight, thus enabling missions leveraging swarms of cubesats capable of science returns not possible with a single large-scale satellite. Additionally, the robustness of the SiC semiconductor allows for operation in extreme conditions such as the hot Venusian surface and the high radiation environment of the Jovian system.
- Published
- 2016
38. Definitive Identification of an Important 4H SiC MOSFET Interface/Near Interface Trap
- Author
-
Aivars J. Lelis, Patrick M. Lenahan, and Corey J. Cochrane
- Subjects
Materials science ,Electrically detected magnetic resonance ,business.industry ,Mechanical Engineering ,Interface (computing) ,Oxide ,Analytical chemistry ,Condensed Matter Physics ,law.invention ,Trap (computing) ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,law ,MOSFET ,Optoelectronics ,General Materials Science ,Field-effect transistor ,Spin (physics) ,business ,Electron paramagnetic resonance - Abstract
We utilize electrically detected magnetic resonance (EDMR) via spin dependent recombination (SDR) to provide a definitive identification of an interface/near interface defect present in a wide variety of 4H SiC/SiO2 metal oxide semiconducting field effect transistors (MOSFETs).
- Published
- 2012
- Full Text
- View/download PDF
39. Electrically Detected Magnetic Resonance in Dielectric Semiconductor Systems of Current Interest
- Author
-
Jason P. Campbell, Corey J. Cochrane, Jason T. Ryan, and Patrick M. Lenahan
- Subjects
Materials science ,Negative-bias temperature instability ,Silicon ,business.industry ,chemistry.chemical_element ,Dielectric ,Semiconductor ,chemistry ,MOSFET ,Optoelectronics ,Field-effect transistor ,business ,Quantum tunnelling ,Leakage (electronics) - Abstract
There is significant interest in the development of new dielectrics and new semiconductor/dielectric systems. Of particular interest are new materials for metal oxide field effect transistor systems and new materials for interlayer dielectrics. The electronic defects which limit the performance of these new material systems are largely unknown. Electron paramagnetic resonance (EPR) has unrivaled analytical power for the identification of the physical and chemical nature of trapping centers in semiconductors and insulators (1). However, the sensitivity of conventional EPR is orders of magnitude too low to make measurements in most present day solid state devices. Two electrically detected magnetic resonance (EDMR) techniques, spin dependent recombination (SDR) and spin dependent trap assisted tunneling (SDT) provide the same analytical power as conventional EPR but, in addition, offer a sensitivity many orders of magnitude higher. This enhanced sensitivity allows measurements to be made in essentially “state of the art” device structures and provide several other significant advantages. EDMR can, under some circumstances, provide information about the physical location and energy levels of deep level defects which play important roles in electronic devices. In this presentation, I’ll discuss EDMR results on low-K dielectric constant films (2), on high-K dielectric films on silicon (3), on near interface/interface traps in SiC MOSFET gate dielectrics (4), on defects which play dominating roles in stress induced leakage currents (5) and the negative bias temperature instability (6) in essentially “state of the art” plasma nitrided oxides in silicon based pMOSFETs. I will also show how energy resolved SDT can provide fairly precise measurements of dielectric defect energy levels and show how the SDR response as a function of gate voltage can provide qualitative information about the physical distribution of interface/near interface defects. ACKNOWLDEGEMENTS Work supported by Intel Corporation, U.S. Army Research Laboratory, GE Global Research, and NIST.
- Published
- 2011
- Full Text
- View/download PDF
40. Physical nature of electrically detected magnetic resonance through spin dependent trap assisted tunneling in insulators
- Author
-
Corey J. Cochrane, Johan van Tol, Patrick M. Lenahan, and Mark A. Anders
- Subjects
010302 applied physics ,Physics ,Spintronics ,Magnetoresistance ,Spins ,Condensed matter physics ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Magnetic field ,Amorphous solid ,Coupling (physics) ,0103 physical sciences ,0210 nano-technology ,Spin (physics) ,Quantum tunnelling - Abstract
We show that electrically detected magnetic resonance (EDMR), through spin dependent trap assisted tunneling (SDTT) in amorphous SiC, exhibits approximately equal amplitudes at very high (8.5 T) and very low (0.013 T) magnetic fields at room temperature. This result strongly supports an SDTT/EDMR model in which spins at two nearby sites involved in a tunneling event are coupled for a finite time in circumstances somewhat analogous to spin pair coupling in the spin dependent recombination/EDMR model of Kaplan, Solomon, and Mott (KSM) [Kaplan, Solomon, and Mott, J. Phys. Lett. 39, 51 (1978)]. Since a comparable near zero magnetic field change in resistance is also observed in these samples, our results support the idea that this magnetoresistance response is also the result of a KSM-like mechanism involving SDTT. Additionally, we observe a large enhancement in SDTT/EDMR at high field (8.5 T) for temperatures below 50 K, which suggests the potential utility of SDTT in spin based quantum computation and other spintronic applications.
- Published
- 2018
- Full Text
- View/download PDF
41. EDMR and EPR Studies of 4H SiC MOSFETs and Capacitors
- Author
-
Kevin Matocha, Jody Fronheiser, Patrick M. Lenahan, Aivars J. Lelis, Brad C. Bittel, and Corey J. Cochrane
- Subjects
Electron nuclear double resonance ,Materials science ,Electrically detected magnetic resonance ,Pulsed EPR ,business.industry ,Mechanical Engineering ,Resonance ,Condensed Matter Physics ,Spectral line ,law.invention ,Capacitor ,Nuclear magnetic resonance ,Mechanics of Materials ,law ,MOSFET ,Optoelectronics ,General Materials Science ,business ,Electron paramagnetic resonance - Abstract
We have extended a magnetic resonance based study of MOS devices to include electrically detected magnetic resonance (EDMR) measurements of fully processed MOSFETs from three facilities as well as conventional electron paramagnetic resonance (EPR) resonance measurements on simple SiC/SiO2 structures. We find close similarity between the conventional EPR and the EDMR spectra.
- Published
- 2010
- Full Text
- View/download PDF
42. Direct Observation of Lifetime Killing Defects in 4H SiC Epitaxial Layers via Spin Dependent Recombination in Transistors
- Author
-
Corey J. Cochrane, Patrick M. Lenahan, and Aivars J. Lelis
- Subjects
Materials science ,Condensed matter physics ,business.industry ,Mechanical Engineering ,Transistor ,Direct observation ,Carrier lifetime ,Condensed Matter Physics ,Epitaxy ,law.invention ,Mechanics of Materials ,law ,Optoelectronics ,General Materials Science ,business ,Electron paramagnetic resonance ,Spin (physics) ,Recombination - Abstract
We have identified a magnetic resonance spectrum associated with minority carrier lifetime killing defects in device quality 4H SiC.
- Published
- 2009
- Full Text
- View/download PDF
43. Miniaturized time-resolved Raman spectrometer for planetary science based on a fast single photon avalanche diode detector array
- Author
-
Corey J. Cochrane, Jordana Blacksberg, George R. Rossman, Erik Alerstam, and Yuki Maruyama
- Subjects
Geologic Sediments ,Photon ,Materials science ,Time Factors ,Materials Science (miscellaneous) ,Instrumentation ,Astronomy ,Planets ,Spectrum Analysis, Raman ,01 natural sciences ,Industrial and Manufacturing Engineering ,010309 optics ,symbols.namesake ,Optics ,Interference (communication) ,0103 physical sciences ,Business and International Management ,Organic Chemicals ,Minerals ,Photons ,Miniaturization ,Planetary surface ,business.industry ,Sulfates ,010401 analytical chemistry ,0104 chemical sciences ,Single-photon avalanche diode ,symbols ,Clay ,Aluminum Silicates ,Time-resolved spectroscopy ,Electronics ,business ,Raman spectroscopy ,Raman scattering - Abstract
We present recent developments in time-resolved Raman spectroscopy instrumentation and measurement techniques for in situ planetary surface exploration, leading to improved performance and identification of minerals and organics. The time-resolved Raman spectrometer uses a 532 nm pulsed microchip laser source synchronized with a single photon avalanche diode array to achieve sub-nanosecond time resolution. This instrument can detect Raman spectral signatures from a wide variety of minerals and organics relevant to planetary science while eliminating pervasive background interference caused by fluorescence. We present an overview of the instrument design and operation and demonstrate high signal-to-noise ratio Raman spectra for several relevant samples of sulfates, clays, and polycyclic aromatic hydrocarbons. Finally, we present an instrument design suitable for operation on a rover or lander and discuss future directions that promise great advancement in capability.
- Published
- 2016
44. Atomic-scale defects involved in the negative-bias temperature instability
- Author
-
Srikanth Krishnan, J. P. Campbell, Anand T. Krishnan, Patrick M. Lenahan, and Corey J. Cochrane
- Subjects
Materials science ,Negative-bias temperature instability ,Silicon ,Condensed matter physics ,Gate dielectric ,Dangling bond ,chemistry.chemical_element ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,chemistry ,Silicon nitride ,MOSFET ,Electronic engineering ,Density of states ,Electrical and Electronic Engineering ,Safety, Risk, Reliability and Quality ,Quantum tunnelling - Abstract
This paper examines the atomic-scale defects involved in a metal-oxide-silicon field-effect-transistor reliability problem called the negative-bias temperature instability (NBTI). NBTI has become the most important reliability problem in modern complementary-metal-oxide-silicon technology. Despite 40 years of research, the defects involved in this instability were undetermined prior to this paper. We combine DC gate-controlled diode measurements of interface-state density with two very sensitive electrically detected magnetic-resonance measurements called spin-dependent recombination (SDR) and spin-dependent tunneling (SDT). An analysis of these measurements provides an identification of the dominating atomic-scale defects involved in NBTI in pure- and plasma-nitrided oxide (PNO)-based devices. We are also able to observe atomic-scale defects involved in HfO2-based devices (although a definitive identification of the dominating defects structure was not possible). Our results in pure- devices indicate an NBTI mechanism which is dominated by the generation of Pb0 and Pb1 interface-state defects. (Pb0 and Pb1 are both silicon dangling-bond defects, in which the central silicon is back-bonded to three other silicon atoms precisely at the interface). This observation is consistent with what most NBTI researchers have assumed. However, our observations in PNO devices contradict with what most NBTI researchers had previously assumed. We demonstrate that the dominating NBTI-induced defect in the plasma-nitrided devices is fundamentally different than those observed in pure-based devices. Our measurements indicate that the new plasma-nitrided NBTI-induced defect's physical location extends into the gate dielectric. The defect participates in both SDR and SDT. Our SDR results strongly indicate that the plasma-nitrided defect has a density of states which is more narrowly peaked than that of centers and is near the middle of the band gap. The high sensitivity of our SDT measurements allow an identification of the physical and chemical nature of this defect through observations of hyperfine interactions. The defects are silicon dangling bonds, in which the central silicon is back-bonded to nitrogen atoms. We call these NBTI-induced defects centers because of the similarities to the centers observed in silicon nitride (the silicon-nitrided center is also a silicon dangling bond in which the silicon atom is back-bonded to nitrogen atoms). The defect identification in plasma-nitrided devices helps to explain the following phenomena: (1) NBTI's enhancement in plasma-nitrided devices; (2) conflicting reports of NBTI-induced interface states and/or bulk traps; and (3) fluorine's ineffectiveness in reducing NBTI in plasma-nitrided devices. We also observe the atomic-scale defects involved in NBTI in HfO2-based devices and find that short- and long-term stressing generates different defects and that these defects are different than those observed in the SiO2 and plasma-nitrided devices. Our results also suggest that the NBTI-induced defects in these devices are physically located in the interfacial layer (not at the interface).
- Published
- 2007
- Full Text
- View/download PDF
45. Quantitative electrically detected magnetic resonance for device reliability studies
- Author
-
Corey J. Cochrane, Michael Mutch, Patrick M. Lenahan, and Mark A. Anders
- Subjects
Reliability (semiconductor) ,Materials science ,Electrically detected magnetic resonance ,Temperature instability ,business.industry ,Radiation damage ,Gate stack ,Microelectronics ,Optoelectronics ,business ,Spin dependent tunneling ,Instability - Abstract
Electrically detected magnetic resonance (EDMR) is a valuable tool for studying a variety of reliability problems, including the negative-bias temperature instability, total ionizing dose radiation damage, and instability in high-K gate stack-based MOS devices. Although conventional high-field EDMR can provide identification of the physical and chemical nature of electrically active reliability dominating defects in microelectronic devices, all of the EDMR studies to date have been limited by one significant shortcoming: EDMR is not quantitative. Although a large EDMR response generally corresponds to a high defect density and a small EDMR response corresponds to a low one, it has not been possible to assign actual numbers to the defect densities detected via EDMR. We've solved this problem.
- Published
- 2014
- Full Text
- View/download PDF
46. Zero/low field SDR and SDT used for atomic scale probes of NBTI and TDDB
- Author
-
Corey J. Cochrane and Patrick M. Lenahan
- Subjects
Condensed Matter::Materials Science ,Negative-bias temperature instability ,Materials science ,Condensed matter physics ,Field (physics) ,Dielectric strength ,MOSFET ,Condensed Matter::Strongly Correlated Electrons ,Time-dependent gate oxide breakdown ,Dielectric ,Atomic units ,Spin-½ - Abstract
This work focuses on the use of a zero- and low-field detection technique of spin dependent recombination and spin dependent tunneling used for studying the bias temperature instabilities in MOSFETs and time dependent dielectric breakdown in this film dielectrics.
- Published
- 2013
- Full Text
- View/download PDF
47. A means to study reliability based defects in fully processed devices utilizing zero-field spin dependent transport
- Author
-
Patrick M. Lenahan and Corey J. Cochrane
- Subjects
Materials science ,business.industry ,Magnetic resonance force microscopy ,Resonance ,Magnetostatics ,Ferromagnetic resonance ,law.invention ,Magnetic field ,Paramagnetism ,Nuclear magnetic resonance ,law ,Spin echo ,Optoelectronics ,Electron paramagnetic resonance ,business - Abstract
Electron paramagnetic resonance (EPR) and electrically detected magnetic resonance (EDMR) are extremely useful techniques that are capable of defect detection in semiconductor structures and fully processed devices, respectively. The complexity of conventional EPR and EDMR spectrometers involves utilization of strong (>3000 G) highly uniform magnetic fields (B 0 ) and high frequency (typically 9 GHz) oscillating magnetic fields (B 1 ) or higher. These components are typically expensive and heavy. In this study, we directly demonstrate that, in the absence of both an oscillating magnetic field and a large static magnetic field, spin dependent recombination (SDR) and spin dependent tunneling (SDT) can be detected at zero magnetic field. In this zero-field detection scheme, hyperfine interactions can be detected which allow for the physical identification of the defects responsible for SDR and SDT. However, we sacrifice the evaluation of a resonance parameter, the g-value. We observe the zero-field phenomenon in multiple solid state electronic components including MOSFETs, BJTs, diodes, and capacitors suggesting its usefulness for semiconducting manufacturers to incorporate simple automated low-field/zero-field EDMR spectrometers into wafer fabrication/probing equipment to study the defects in solid-state electronics during fabrication. Because only very low fields are required, low field EDMR can be performed easily and inexpensively.
- Published
- 2012
- Full Text
- View/download PDF
48. ChemInform Abstract: Electrically Detected Magnetic Resonance in Dielectric Semiconductor Systems of Current Interest
- Author
-
Jason P. Campbell, Corey J. Cochrane, Patrick M. Lenahan, and Jason T. Ryan
- Subjects
Semiconductor ,Negative-bias temperature instability ,business.industry ,Chemistry ,Orders of magnitude (temperature) ,MOSFET ,Optoelectronics ,Field-effect transistor ,General Medicine ,Dielectric ,business ,Quantum tunnelling ,Leakage (electronics) - Abstract
There is significant interest in the development of new dielectrics and new semiconductor/dielectric systems. Of particular interest are new materials for metal oxide field effect transistor systems and new materials for interlayer dielectrics. The electronic defects which limit the performance of these new material systems are largely unknown. Electron paramagnetic resonance (EPR) has unrivaled analytical power for the identification of the physical and chemical nature of trapping centers in semiconductors and insulators (1). However, the sensitivity of conventional EPR is orders of magnitude too low to make measurements in most present day solid state devices. Two electrically detected magnetic resonance (EDMR) techniques, spin dependent recombination (SDR) and spin dependent trap assisted tunneling (SDT) provide the same analytical power as conventional EPR but, in addition, offer a sensitivity many orders of magnitude higher. This enhanced sensitivity allows measurements to be made in essentially “state of the art” device structures and provide several other significant advantages. EDMR can, under some circumstances, provide information about the physical location and energy levels of deep level defects which play important roles in electronic devices. In this presentation, I’ll discuss EDMR results on low-K dielectric constant films (2), on high-K dielectric films on silicon (3), on near interface/interface traps in SiC MOSFET gate dielectrics (4), on defects which play dominating roles in stress induced leakage currents (5) and the negative bias temperature instability (6) in essentially “state of the art” plasma nitrided oxides in silicon based pMOSFETs. I will also show how energy resolved SDT can provide fairly precise measurements of dielectric defect energy levels and show how the SDR response as a function of gate voltage can provide qualitative information about the physical distribution of interface/near interface defects. ACKNOWLDEGEMENTS Work supported by Intel Corporation, U.S. Army Research Laboratory, GE Global Research, and NIST.
- Published
- 2012
- Full Text
- View/download PDF
49. Electrically detected magnetic resonance study of a near interface trap in 4H SiC MOSFETs
- Author
-
Aivars J. Lelis, Patrick M. Lenahan, and Corey J. Cochrane
- Subjects
Materials science ,Silicon ,business.industry ,Wide-bandgap semiconductor ,Dangling bond ,chemistry.chemical_element ,law.invention ,chemistry.chemical_compound ,Nuclear magnetic resonance ,chemistry ,law ,Vacancy defect ,MOSFET ,Silicon carbide ,Optoelectronics ,Field-effect transistor ,business ,Electron paramagnetic resonance - Abstract
It is well known that 4H silicon carbide (SiC) based metal oxide silicon field effect transistors (MOSFETs) have great promise in high power and high temperature applications. The reliability and performance of these MOSFETs is currently limited by the presence of SiC/SiO 2 interface and near interface traps which are poorly understood. Conventional electron paramagnetic resonance (EPR) studies of silicon samples have been utilized to argue for carbon dangling bond interface traps [1]. For several years, with several coworkers, we have explored these silicon carbide based MOSFETs with electrically detected magnetic resonance (EDMR), [2,3] establishing a connection between an isotropic EDMR spectrum with g=2.003 and deep level defects in the interface/near interface region of SiC MOSFETs. We tentatively linked the spectrum to a silicon vacancy or closely related defect. This assessment was tentative because we were not previously able to quantitatively evaluate the electron nuclear hyperfine interactions at the site. Through multiple improvements in EDMR hardware and data acquisition software, we have achieved a very large improvement in sensitivity and resolution in EDMR, which allows us to detect side peak features in the EDMR spectra caused by electron nuclear hyperfine interactions. This improved resolution allows far more definitive conclusions to be drawn about defect structure. In this work, we provide extremely strong experimental evidence identifying the structure of that defect. The evidence comes from very high resolution and sensitivity “fast passage” (FP) mode [4, 5] electrically detected magnetic resonance (EDMR) or FPEDMR of the ubiquitous EDMR spectrum.
- Published
- 2011
- Full Text
- View/download PDF
50. Defects in HfO2 Based Dielectric Gate Stacks
- Author
-
Jason T. Ryan, Corey J. Cochrane, John F. Conley, and Patrick M. Lenahan
- Subjects
Materials science ,Silicon ,business.industry ,Gate dielectric ,chemistry.chemical_element ,Dielectric ,Oxygen ,Hafnium ,law.invention ,chemistry ,Gate oxide ,law ,Optoelectronics ,business ,Electron paramagnetic resonance ,High-κ dielectric - Abstract
We report on both conventional electron paramagnetic resonance (EPR) measurements of fully processed HfO2 based dielectric films on silicon and on electrically detected magnetic resonance (EDMR) measurements of fully processed HfO2 based MOSFETs. The magnetic resonance measurements indicate the presence of oxygen vacancy and oxygen interstitial defects within the HfO2 and oxygen deficient silicons in the interfacial layer. The EDMR results also indicate the generation of at least two defects when HfO2 based transistors are subjected to significant negative bias at modest temperature. Our results indicate generation of multiple interface/near interface defects, likely involving coupling with nearby hafnium atoms.
- Published
- 2009
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