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1. An Examination into the Effects of a Nutraceutical Supplement on Cognition, Stress, Eye Health, and Skin Satisfaction in Adults with Self-Reported Cognitive Complaints: A Randomized, Double-Blind, Placebo-Controlled Trial

Author

Lopresti, Adrian L, primary, Smith, Stephen James, additional, Riggs, Melanie L, additional, Major, Rebecca A, additional, Gibb, Tanner G, additional, Wood, Steven M, additional, Hester, Shelly N, additional, and Knaggs, Helen E, additional

Published
2024
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2. Development of transition edge sensor distributed read-out imaging devices for applications in X-ray astronomy

Author

Smith, Stephen James

Subjects
522
Abstract

This thesis is concerned with the development of, position-sensitive, Transition Edge Sensors (TES) operating at cryogenic temperatures (~ 0.1 K). The Distributed Read-Out Imaging Device (DROID) concept uses TES read-out at both ends of a linear X-ray absorber, to derive, through heat diffusion, both spectral and spatial information. Potentially, DROIDs offer a simpler technological alternative to the development of large area pixel arrays for future X-ray space observatories (Chapter 1). Chapter 2 presents a comprehensive review of the theory of microcalorimeter detectors. A finite-element model is established in Chapter 3, to numerically simulate the response of the DROID to an X-ray photon, as well as the noise spectral density at the detector outputs, including frequency dependent correlations between the two TESs. In Chapter 4 this model is used to implement pre-existing algorithms, based on the use of the optimal filter, to calculate the position and energy resolution along the length of experimental DROID designs. We show that these algorithms do not lead to optimum performance under all conditions and then derive the true optimal filters, based on least-squares minimisation of the total noise power in the DROID. By numerical simulation we show that significant improvements in both the energy and in particular, the position resolution, are theoretically possible. The design and experimental characterisation of two prototype DROIDs are described in Chapter 6 and 7, using the equipment described in Chapter 5. The first X-ray results from a prototype TES DROID, using single TES read-out, are reported. These results demonstrate proof of concept, confirming spatial sensitivity along the DROID, through the actual spectral and spatial resolutions are limited by the availability of only a single read-out channel.

Published
2006

6. Parametric Characterization of TES Detectors Under DC Bias

Author

Chiao, Meng P, Smith, Stephen James, Kilbourne, Caroline A, Adams, Joseph S, Bandler, Simon R, Betancourt-Martinez, Gabriele L, Chervenak, James A, Datesman, Aaron M, Eckart, Megan E, Ewin, Audrey J, Finkbeiner, Fred Michael, Figueroa-Feliciano, Enectali, Kelley, Richard L, Lee, Sang Jun, Leutenegger, Maurice, Porter, Frederick Scott, Sadleir, John E, Wassell, Edward J, and Yoon, Wonsik

Subjects
Astrophysics, Instrumentation And Photography
Abstract

The X-ray integrated field unit (X-IFU) in European Space Agency's (ESA's) Athena mission will be the first high-resolution X-ray spectrometer in space using a large-format transition-edge sensor microcalorimeter array. Motivated by optimization of detector performance for X-IFU, we have conducted an extensive campaign of parametric characterization on transition-edge sensor (TES) detectors with nominal geometries and physical properties in order to establish sensitivity trends relative to magnetic field, dc bias on detectors, operating temperature, and to improve our understanding of detector behavior relative to its fundamental properties such as thermal conductivity, heat capacity, and transition temperature. These results were used for validation of a simple linear detector model in which a small perturbation can be introduced to one or multiple parameters to estimate the error budget for X-IFU. We will show here results of our parametric characterization of TES detectors and briefly discuss the comparison with the TES model.

Published
2016
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7. Magnetic Field Dependence of the Critical Current in S-N Bilayer Thin Films

Author

Sadleir, John E, Lee, Sang-Jun, Smith, Stephen James, Bandler, Simon, Chervenak, James, Kilbourne, Caroline A, Finkbeiner, Fred M, Porter, Frederick S, Kelley, Richard L, Adams, Joseph S, Eckart, Megan E, Busch, Sarah, and Porst, Jan-Patrick

Subjects
Solid-State Physics, Astronomy
Abstract

Here we investigate the effects a non-uniform applied magnetic field has on superconducting transition-edge sensors (TESs) critical current. This has implications on TES optimization. It has been shown that TESs resistive transition can be altered by magnetic fields. We have observed critical current rectification effects and explained these effects in terms of a magnetic self-field arising from asymmetric current injection into the sensor. Our TES physical model shows that this magnetic self-field can result in significantly degraded or improved TES performance. In order for this magnetically tuned TES strategy to reach its full potential we are investigating the effect a non-uniform applied magnetic field has on the critical current.

Published
2013

8. Optimization of Time- and Code-Division-Multiplexed Readout for Athena X-IFU

Author

Doriese, W. Bertrand, primary, Bandler, Simon R., additional, Chaudhuri, Saptarshi, additional, Dawson, Carl S., additional, Denison, Edward V., additional, Duff, Shannon M., additional, Durkin, Malcolm, additional, FitzGerald, Connor T., additional, Fowler, Joseph W., additional, Gard, Johnathon D., additional, Hilton, Gene C., additional, Irwin, Kent D., additional, Joe, Young Il, additional, Morgan, Kelsey M., additional, O'Neil, Galen C., additional, Pappas, Christine G., additional, Reintsema, Carl D., additional, Rudman, David A., additional, Smith, Stephen James, additional, Stevens, Robert W., additional, Swetz, Daniel S., additional, Szypryt, Paul, additional, Ullom, Joel N., additional, Vale, Leila R., additional, Weber, Joel C., additional, and Young, Betty A., additional

Published
2019
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9. Fabrication of Magnetic Calorimeter Arrays With Buried Wiring

Author

Devasia, Archana M., primary, Balvin, Manuel A., additional, Bandler, Simon R., additional, Bolkhovsky, Vladimir, additional, Nagler, Peter C., additional, Ryu, Kevin, additional, Smith, Stephen James, additional, Stevenson, Thomas R., additional, and Yoon, Wonsik, additional

Published
2019
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10. Parametric Characterization of TES Detectors Under DC Bias

Author

Chiao, Meng P., primary, Smith, Stephen James, additional, Kilbourne, Caroline A., additional, Adams, Joseph S., additional, Bandler, Simon R., additional, Betancourt-Martinez, Gabriele L., additional, Chervenak, James A., additional, Datesman, Aaron M., additional, Eckart, Megan E., additional, Ewin, Audrey J., additional, Finkbeiner, Fred Michael, additional, Figueroa-Feliciano, Enectali, additional, Kelley, Richard L., additional, Lee, Sang Jun, additional, Leutenegger, Maurice, additional, Porter, Frederick Scott, additional, Sadleir, John E., additional, Wassell, Edward J., additional, and Yoon, Wonsik, additional

Published
2017
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11. Fabrication of X-Ray Microcalorimeter Focal Planes Composed of Two Distinct Pixel Types

Author

Wassell, Edward J., primary, Adams, Joseph S., additional, Bandler, Simon R., additional, Betancourt-Martinez, Gabriele L., additional, Chiao, Meng P., additional, Chang, Meng Ping, additional, Chervenak, James A., additional, Datesman, Aaron M., additional, Eckart, Megan E., additional, Ewin, Audrey J., additional, Finkbeiner, Fred Michael, additional, Ha, Jong Yoon, additional, Kelley, Richard, additional, Kilbourne, Caroline A., additional, Miniussi, Antoine R., additional, Sakai, Kazuhiro, additional, Porter, Frederick Scott, additional, Sadleir, John E., additional, Smith, Stephen James, additional, Wakeham, Nicholas A., additional, and Yoon, Wonisk, additional

Published
2017
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12. Design and Performance of Hybrid Arrays of Mo/Au Bilayer Transition-Edge Sensors

Author

Yoon, Wonsik, primary, Adams, Joseph S., additional, Bandler, Simon R., additional, Betancourt-Martinez, Gabriele L., additional, Chiao, Meng P., additional, Chang, Meng-Ping, additional, Chervenak, James A., additional, Datesman, Aaron, additional, Eckart, Megan E., additional, Ewin, Audrey J., additional, Finkbeiner, Fred Michael, additional, Ha, Jong Yoon, additional, Kelley, Richard, additional, Kilbourne, Caroline A., additional, Miniussi, Antoine R., additional, Porter, Frederick Scott, additional, Sadleir, John E., additional, Sakai, Kazuhiro, additional, Smith, Stephen James, additional, Wakeham, Nicholas A., additional, and Wassell, Edward, additional

Published
2017
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13. Electron-Beam Deposition of Superconducting Molybdenum Thin Films for the Development of Mo/Au TES X-ray Microcalorimeter

Author

Finkbeiner, Fred Michael, primary, Adams, Joseph S., additional, Bandler, Simon R., additional, Betancourt-Martinez, Gabriele L., additional, Brown, Ari David, additional, Chang, Meng-Ping, additional, Chervenak, James A., additional, Chiao, Meng P., additional, Datesman, Aaron M., additional, Eckart, Megan E., additional, Kelley, Richard L., additional, Kilbourne, Caroline A., additional, Miniussi, Antoine R., additional, Moseley, Samuel J., additional, Porter, Frederick Scott, additional, Sadleir, John E., additional, Sakai, Kazuhiro, additional, Smith, Stephen James, additional, Wakeham, Nicholas A., additional, Wassell, Edward J., additional, and Yoon, Wonisk, additional

Published
2017
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14. A phase I trial investigating pulsatile erlotinib in combination with gemcitabine and oxaliplatin in advanced biliary tract cancers

Author

Goff, Laura W., primary, Cardin, Dana B., additional, Whisenant, Jennifer G., additional, Du, Liping, additional, Koyama, Tatsuki, additional, Dahlman, Kimberly B., additional, Salaria, Safia N., additional, Young, Ruth T., additional, Ciombor, Kristen K., additional, Gilbert, Jill, additional, Smith, Stephen James, additional, Chan, Emily, additional, and Berlin, Jordan, additional

Published
2016
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17. Development, of Position-Sensitive Transition-Edge Sensor X-Ray Detectors.

Author

Smith, Stephen James, Bandler, Simon R., Brekosky, Regis P., Brown, Ari-David, Chervenak, Jay A., Eckart, Megan E., Figueroa-Feliciano, Encetali, Finkbeiner, Fred M., Kelley, Richard L., Kilbourne, Caroline A., Porter, Frederick Scott, and Sadleir, John E.

Subjects
*NOISE measurement, *CALORIMETERS, *THERMAL conductivity, *IMPEDANCE spectroscopy, *DETECTORS
Abstract

We report on the development of position-sensitive transition-edge sensors (PoST's) for future X-ray astronomy missions such as the International X-ray Observatory (IXO), under study by NASA and ESA. PoST's consist of multiple absorbers each with a different thermal coupling to one or more transition-edge sensors (TESs). This results in a characteristic pulse shape for each absorber element and allows position discrimination. PoST development is motivated by a desire to achieve maximum focal-plane area with the fewest number of readout channels. We report detailed characterization of our single TES PoST's or Hydras, which consist of four electroplated AuIBi absorbers coupled to a low noise Mo/Au TES. Using a numerical model of the Hydra we fit to measured complex impedance curves and determine device parameters that allow us to accurately reproduce the measured pulse shapes and noise spectra. Results from Hydras with different internal thermal conductances reveal the trade-offs in optimizing for energy resolution or position-sensitivity. We report a best achievable energy resolution of <6.0 eV across all pixels for a device with transition temperature of 86 mK, coupled with straightforward position discrimination by rise-time. [ABSTRACT FROM AUTHOR]

Published
2009
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