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Jacob D Willig-Onwuachi

Jake Willig-Onwuachi portrait image
Associate Professor
Department Chair of Physics

Using physics to solve applied problems is an exciting and rewarding challenge for me.  In pursuing this challenge over the years, I have conducted experimental and computational physics research projects in a broad range of areas, including plasma physics, industrial physics, radiofrequency (RF) engineering, and imaging physics.  Magnetic resonance imaging (MRI) is a particularly interesting and exciting field that is a great example of physics in action. Physics serves as a foundation for MRI—from the basic principles to the newest technical design challenges.  

My research is based on using the physics behind MRI to improve medicine through technological advancements or the development of new imaging techniques, e.g., acquiring images faster, making images more accurate, or designing shorter scanners for increased patient access and reduced claustrophobia.  My recent work has focused primarily on parallel MRI (which exploits redundancy in the data acquired ‘in parallel’ from multiple detector coils), image reconstruction, and RF coils and detection.  

Selected Research Projects and Students

  • Coil-by-coil Non-linear MRI Reconstruction - Anne Ramey '17 
  • Non-proton NMR/MRI - Fatemeh Elahi '12, Andrew Marcum '12, Oleksandr (Sasha) Kuzura '17
  • Quantum vs Classical: an exploration of spin coherence - Wenyang Qian '12, Da Hyeong Jang '18
  • MRI motion correction using multiple detectors - Paden Roder '10, Illya Tyschenko '11
  • MRI radiofrequency coil characterization, how to measure quality factor - Geoff Jacobs '09, Abel Assefa '08
  • Imaging on a tabletop with Magritek's Terranova earth's field scanner - Yuyang Fan '11
  • Dielectric resonance and wavelength effects - Prabal Adhikari '09

Selected Publications

  • Wiens C, McCurdy C, Willig-Onwuachi J, and McKenzie C.  R-2*-Corrected Water-Fat Imaging Using Compressed Sensing and Parallel Imaging.  Magnetic Resonance in Medicine 2014; 71: 608-616.
  • Seo Y, Willig-Onwuachi J, and Walton J.  Magnetic resonance thermal imaging combined with SMASH navigators in the presence of motion. Journal of Applied Clinical Medical Physics 2012; 13: 172-187.
  • Wiens C, Kisch S, Willig-Onwuachi J, and McKenzie C.  Computationally Rapid Method of Estimating SNR for Phased Array Image Reconstructions.  Magnetic Resonance in Medicine 2011; 66: 1192-1197.
  • Peng B, Walton J, Cherry S, Willig-Onwuachi J.  Studies of the interactions of an MRI system with the shielding in a combined PET/MRI scanner.  Physics in Medicine and Biology 2010; 55: 265-280.
  • Willig-Onwuachi J, Eagan TP, Shvartsman ShM, Brown RW.  Designer RF Field Profiles for Parallel Imaging Applications.  Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering 2005; 27B: 75-85.
  • Willig-Onwuachi J, Yeh EN, Grant AK, Ohlinger MA, McKenzie CA, Sodickson DK. Phase-constrained parallel MR image reconstruction.  Journal of Magnetic Resonance 2005; 176:187-198.

Other Publications

  • Rosenblum D, with Ben-Asher N, Case M, Emens E, Hernandez-Truyol B, Gutierrez V, Ikemoto L, Onwuachi-Willig A, Willig-Onwuachi J, Mutcherson K, Siegelman P, and Jones B. Pregnant Man?: A Conversation. Yale Journal of Law and Feminism 2010; 22: 207-278.
  • Onwuachi-Willig A, Willig-Onwuachi J. A House Divided: Housing Discrimination and the Invisibility of the Multiracial Family. Harvard Civil Rights Civil Liberties Law Review 2009; 44: 231-253.
  • Acknowledging Loving in the Multiracial Family, in LOVING IN A "POST-RACIAL" WORLD: RETHINKING RACE, SEX AND MARRIAGE (Kevin Noble Maillard & Rose Cuison Villazor, eds., forthcoming Cambridge University Press 2011).
  • Onwuachi-Willig A, Willig-Onwuachi J. “Now Each Citizen Can Proclaim ‘I Love You, and We Can Live in Iowa.’” Iowa City Press Citizen. Apr. 4, 2009. (Invited)
  • Onwuachi-Willig A, Willig-Onwuachi J. “Iowa Supreme Court Should Again Be a Pioneer.” Iowa City Press Citizen. Dec. 9, 2008: 9A.



Campus Phone: 

(641) 269-4873


Grinnell College

College Graduation Year: 


faculty info column 1

On-Campus Address: 

1033 Science
Grinnell, IA 50112
United States

Education / Degrees: 

Postdoc (MRI), 2001-2003, Harvard Medical School/Beth Israel Deaconess Medical Center; Ph.D., Physics, Case Western Reserve University, 2001; M.S., Physics, University of Iowa, 1997; B.A., Grinnell College, 1995

Courses Taught: 

Phy-131: General Physics I with Lab; Phy-132: General Physics II with Lab; Phy-232: Modern Physics; Phy-335: Electromagnetic Theory; Phy-337: Optics and Wave Phenomena; Phy-462: Advanced Laboratory; Tutorial: "The Social Construction of Obama"; Tutorial: "It's All News to Me"

Primary Academic Interest: 

Magnetic Resonance Imaging

Department Chair: