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A Highly Linear Calibration Metric for TES X-ray Microcalorimeters



Christine G. Pappas, Joseph W. Fowler, Douglas A. Bennett, William B. Doriese, Young I. Joe, Kelsey M. Morgan, Galen C. O'Neil, Joel N. Ullom, Daniel S. Swetz


Transition-edge sensor X-ray microcalorimeters are usually calibrated empirically, as the most widely-used calibration metric, optimal filtered pulse height (OFPH), in general has an unknown dependance on photon energy, Eγ. Because the calibration function can only be measured at specific points where photons of a known energy can be produced, this unknown dependence of OFPH on Eγ leads to calibration errors and the need for time-intensive calibration measurements and analysis. A calibration metric that is nearly linear as a function of Eγ could help alleviate these problems. In this work, we assess the linearity of a physically motivated calibration metric, EJoule. We measure calibration pulses in the range 4.5 keV< Eγ <9.6 keV with detectors optimized for 6 keV photons to compare the linearity properties of EJoule to OFPH. In these test data sets, we find that EJoule fits a linear function an order of magnitude better than OFPH. Furthermore, calibration functions using EJ, an optimized version of EJoule, are linear within the 2-3 eV noise of the data.
Journal of Low Temperature Physics


transition-edge sensor X-ray microcalorimeters, optimal filtered pulse height, OFPH, photon energy, E<sub>?</sub>, photons, calibration errors, E<sub>Joule</sub>, detectors, linearity properties


Pappas, C. , Fowler, J. , Bennett, D. , Doriese, W. , Joe, Y. , Morgan, K. , O'Neil, G. , Ullom, J. and Swetz, D. (2018), A Highly Linear Calibration Metric for TES X-ray Microcalorimeters, Journal of Low Temperature Physics, [online], (Accessed April 24, 2024)
Created August 2, 2018, Updated June 29, 2020