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Christopher M. Heirwegh

Photo of Christopher Heirwegh


4800 Oak Grove Drive
M/S 183-301

Pasadena, CA 91109





Curriculum Vitae:

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Member of:

Astrobiology and Ocean Worlds


Chris is an applied physicist with expertise in the fundamental physics of X-ray fluorescence (XRF) and charged particle spectroscopy techniques. Prior to JPL, while at the University of Guelph, Chris supported the analysis of data returned from the alpha-particle X-ray spectrometer (APXS) instrument installed on NASA’s Curiosity rover.

Here at JPL, Chris serves as a co-investigator and elemental calibration lead for NASA’s Planetary Instrument for X-ray Lithochemistry (PIXL), an instrument installed on the arm of the Mars 2020 Perseverance Rover. Also at JPL, Chris leads an instrument team working to develop a prototype X-ray that utilizes pyroelectric technology for in situ planetary and lunar exploration. Chris hopes to develop the prototype instrument so that it might serve as a low-cost, low-power, robust alternative to existing radioactive and X-ray tube source technologies.

Chris also maintains a long-lasting interest in pure scientific research, directed at improving physics fundamental parameters used in X-ray spectroscopy analysis.


  • Ph.D. Applied Physics, University of Guelph (2014)
  • M.Sc. Medical Physics, McMaster University (2009)
  • B.Sc. Science, McMaster University (2004)

Professional Experience

  • Scientist, Jet Propulsion Laboratory (2018 – present)
  • Sessional Lecturer, University of Guelph (2015, 2021)
  • JPL Postdoctoral Scholar, Jet Propulsion Laboratory (2018)
  • Caltech Postdoctoral Fellow, Jet Propulsion Laboratory (2016 – 2018)
  • Course Instructor, University of Guelph (2015)
  • Postdoctoral Fellow in Physics, University of Guelph (2014 – 2016)
  • Research Assistant (doctorate), University of Guelph (2009 – 2014)
  • Research Assistant (masters), McMaster University (2006 – 2009)
  • Teaching assistant (McMaster and U of Guelph (2004 – 2012)
  • Summer Research Assistant, Juravinski Cancer Centre (2003)

Community Service

Chris serves as an academic reviewer for articles written within the field of X-ray spectroscopy from journals: Icarus, the Journal of Synchrotron Radiation, Advances in X-ray Analysis, Nuclear Instruments and Methods A and B and X-ray Spectrometry.

Following the success of the Perseverance Rover landing, Chris has participated in multiple interviews and has delivered several public talks to share his experience on the Mars 2020 mission.

Chris continues to mentor students through the JPL Summer Internship Program and periodically teaches undergraduate and graduate students as a sessional lecturer.

Research Interests

  • Development of X-ray instrument concepts for use on spacecraft
  • Application of spectroscopic analysis techniques to planetary science research
  • Semiconductor detector physics and spectral line-shapes peak fitting
  • X-ray fundamental parameter accuracy refinement
  • Energy- and wavelength-dispersive X-ray analysis methods
  • Charge-induced multiple-shell vacancy effects on X-ray emission

Selected Awards

  • Invited Speaker – European X-ray Spec. Assoc. Virtual Meeting, 2021
  • Invited Speaker – 70th Denver X-ray Conference, Westminster, Colorado, 2021
  • Certificate of Recognition - Dedication to completion of PXL Flight Sensor Assembly, 2020
  • Invited Speaker – Physics Dept. Colloquium, University of Guelph, Guelph, Canada, 2020
  • Mentoring in Action – JPL Program Completion, 2019
  • Invited Talk – 67th Denver X-ray Conference, Colorado, 2018
  • Best Poster Award – 2nd place, 14th PIXE conference, Somerset West, South Africa, 2015

Selected Publications

  • Heirwegh, C.M. Elam W.T., O’Neil, L.P. The Focused Beam X-ray Fluorescence Elemental Quantification Software Package PIQUANT, Spectrochim. Acta B, 2021 (Accepted, pending revision).
  • Heirwegh, C.M., Clark, B.C., Elam, W.T., Liu, Y., O’Neil, L.P., Sinclair, K.P. Tice, M., Hurowitz, J.A., Allwood, A.C., Calibrating the PIXL Instrument for Elemental Analysis of Mars, 2021 LPSC Abstract, poster presentation.
  • Campbell, J.L., Cureatz, D. J. T., Flannigan, E. L., Heirwegh, C. M., Maxwell, J.A., Russell, J. L., Taylor, S.M., The Guelph PIXE Software Package V. Nucl. Instrum. Meth. B., 2021 (Accepted, pending revision).
  • VanBommel, S.J., Berger, J.A., Rampe, E.B., Heirwegh, C.M., In-Situ X-ray Spectrometers in Space Exploration, in Advances in Portable X-ray Fluorescence Spectrometry - Instrumentation, Application and Interpretation, publisher: The Royal Society of Chemistry, 2021.
  • Allwood, A.C., Wade, L.A., Foote, M.C. et al. PIXL: Planetary Instrument for X-ray Lithochemistry (vol 216, 134, 2020), Space Sci. Rev. 217 (2021) 28.
  • Allwood, A.C., Wade, L.A., Foote, M.C. et al. PIXL: Planetary Instrument for X-ray Lithochemistry, Space Sci. Rev. 216 (2020) 134.
  • Allwood A C, Rosing M T, Flannery D T, Hurowitz J A and Heirwegh C M, “Reassessing Evidence of Life in 3,700 million year old rocks of Greenland,” Nature 563 (2018) 241 – 244.
  • Heirwegh C M, Elam W T, Flannery D T and Allwood A C, An empirical derivation of the x-ray optic transmission profile used in calibrating the Planetary Instrument for X-ray Lithochemistry (PIXL) for Mars 2020, Powder Diffraction Journal 33 (2018) 162 – 165.
  • Heirwegh C M, Petric M, Fazinić S, Kavčič M, Božičević Mihalić I, Schneider J, Zamboni I, and Campbell J L, Multiple ionization X-ray satellites of Mg, Al and Si in alpha particle PIXE, Nucl. Instrum. Meth. B. 428 (2018) 9 – 16.
  • Menachekanian S, Flannery D T, Heirwegh C M, Tuite M L, Jamieson C S, Hodyss R, Williford K, “Investigating photochemical effects of micro-XRF analysis on common geochemical compounds,” Advances in X-Ray Analysis (2018) 61.
  • Campbell J L, Ganly B, Heirwegh C M and Maxwell J A, Separation of detector non-linearity issues and multiple ionization satellites in alpha-particle PIXE, Nucl. Instrum. Meth. B. 414 (2018) 38 – 44.
  • Flannigan E L, Heirwegh C M and Campbell J L, Role of the mass attenuation coefficient database in standardization of a silicon drift X-ray detector for PIXE analysis, X-Ray Spectrom. 47 (2018) 63 - 71.
  • Campbell J L, Heirwegh C M and Ganly B, Non-linearity issues and multiple ionization satellites in the PIXE portion of spectra from the Mars alpha particle X-ray spectrometer, Nucl. Instrum. Meth. B 383 (2016) 143 – 151.
  • Heirwegh C M, Campbell J L and Czamanske G K, Refinement of of major- and minor-element PIXE analysis of rocks and minerals, Nucl. Instrum. Meth. B 336 (2016) 40 - 50.
  • Heirwegh C M, Pradler I and Campbell J L, 2015 Choice of mass attenuation coefficients for PIXE analysis of silicate minerals and rocks, X-ray Spectrom. 44 (2015) 63 - 68.
  • Heirwegh C M, Pradler I and Campbell J L, 2013 An accuracy assessment of photo-ionization cross-section databases for 1-2 keV x-rays in light elements using PIXE, J. Phys. B: At. Mol. Opt. Phys. 46 (2013) 185602.