Certified and Experienced

All our services are performed and supervised by certified medical physicists that have extensive commissioning experience working in the US and in Europe. With a robust background in both clinical settings and technical commissioning, our team members are experts in the most advanced treatment techniques and planning systems available. Their proficiency encompasses a wide range of specialized procedures including Volumetric Modulated Arc Therapy (VMAT, Rapid Arc), Image Guided Radiation Therapy (IGRT), Stereotactic Radiosurgery (SRS, HyperArc), Stereotactic Body Radiation Therapy (SBRT), Adaptive Radiotherapy, and more.

Gloria P. Beyer, Ph.D., DABR

Chief Medical Physicist and Manager

Gloria P. Beyer completed her Ph.D. at the University of South Florida and her two M.S. at the University of Florida and Florida State University.  She is board certified by the American Board of Radiology and has many years of experience as a medical physicist having worked for both vendors and clinics (e.g., Varian Medical Systems and Sicel Technologies Inc.).  In 2004, she founded Medical Physics Services, LLC (“MPS”), a company dedicated to providing commissioning and clinical implementation support for radiation therapy equipment.  MPS incorporated its European subsidiary, Medical Physics Services International Limited (“MPSi”) in 2008 in response to an increasing demand in European countries for MPS’s services.

Dr. Beyer remains the driving force behind MPS and MPSi serving in dual roles as the company’s Chief Medical Physicist and as its Managing Member.  She has authored numerous articles and book chapters relating to various aspects of medical physics and presents regularly at professional meetings in the US and international locations.  Dr. Beyer regularly provides instruction on topics related to medical physics and has served as an adjunct professor at The University of Texas M.D. Anderson Cancer Center and at Oregon State University. She is active in various professional associations in the US and in Europe, having served as an officer for the FL-AAPM and most recently working with the WGEBQA Group of the AAPM.  

Gloria enjoys spending time in the mountains and is also an avid runner, having recently completed the Boston Marathon and competed in several international master athletics championships.

James Atherton, Ph.D., DABR

Senior Medical Physicist

Jim Atherton is originally from New York City and received his Ph.D. in medical physics from the University of Florida. He has worked at Columbia-Presbyterian College of Physicians and Surgeons as an instructor in Clinical Radiology. He has also worked as a staff physicist in Radiation Oncology at Memorial Sloan-Kettering Cancer Center and as Chief Physicist at several Cancer centers in Florida including the Cleveland Clinic (Vero Beach). He is certified in both Therapeutic and Diagnostic Radiological Physics by the ABR.

Dr. Atherton has extensive experience in radiation shielding design and safety surveys; acceptance testing, commissioning, and quality assurance of all aspects of medical linear accelerators, radiation treatment planning systems, radiation dosimetry systems, and record and verify/oncology information systems.   He is active with the professional associations, having served as officer of the FL-AAPM and as Guest Associate Editor for the Medical Physics journal.  

Jim is a dedicated CrossFit athlete and a fan of Formula 1 Racing, rugby and all things travel-related

Kent Hale Larsen, Ph.D., DABR, CHP

Senior Medical Physicist

Kent Hale Larsen received his Ph.D. in physics from Vanderbilt University and is board certified by both the American Board of Radiology and the American Board of Health Physics.  Dr. Larsen has published in numerous professional journals and has worked as an aassistant professor of radiology at the Medical College of Georgia and as adjunct professor in physics at the University of South Florida.

Dr. Larsen worked as a medical physicist and radiation safety officer at several hospitals and radiation oncology clinics before joining MPS as its Senior Medical Physicist and Radiation Safety Officer.  In addition to his commissioning work at MPS, he is the creative force behind the company’s proprietary data analysis tools.

Kent is an avid musician and can frequently be found playing music long into the night with various groups of friends.  

Rachel A. Ross, M.S., DABR

Medical Physicist

For over three decades, Rachel Ross has devoted herself to improving patient care in the field of radiation oncology.  She began as a dosimetrist prior to receiving her master’s degree in biomedical physics from UCLA in 1997.  Rachel is board certified in therapeutic medical physics by the American Board of Radiology and in dosimetry by the Medical Dosimetrist Certification Board.

Her clinical experience includes acting as the chief physicist and radiation safety officer for Comprehensive Blood and Cancer Center located in California.  In this dual role, Rachel established a brand-new radiation oncology department and was an early adopter and advocate of virtual simulations in a clinical setting including SRS and IMRT.  

In 2005, Rachel joined Varian Medical Systems as a clinical applications specialist in medical physics.  Rachel completed her tenure with Varian acting as a global product specialist for the physics helpdesk enabling her to advise customers on some of the most cutting-edge technology in the radiation oncology field.  As her clinical knowledge increased, her expertise was recognized, and she acted in various critical roles at Varian including as a physics instructor and as an on-site trainer for high profile customers.  

When she is not working, Rachel enjoys traveling with her husband. They have been to all seven continents and are actively seeking places they have not been to before.  In her spare time, she also likes to run, downhill ski, mountain bike, and swim with her dog Ziggy. 

Hans Christian Beyer, J.D.

Chief Operating Office

Hans Christian Beyer is an experienced business attorney and entrepreneur. Mr. Beyer holds an honors degree in economics from the University of Michigan as well as a law degree from the University of Michigan Law School. He is a graduate of the U.S. Marine Corps.’s Officer Candidate School in Quantico, Virginia.

In addition to his work as a business attorney, Mr. Beyer has substantial experience in the business world. He has founded, run, and sold successful businesses and acts as a board member for both public and private companies. Mr. Beyer has acted as legal counsel to Medical Physics Services, LLC since its inception in 2004 and now acts as both the company’s Chief Operating Officer and its general counsel.

Christian enjoys a variety of outdoor activities from ice climbing in the mountains to specialized SCUBA diving in the seas.

Dana Brown Larsen, R.T.T.

Project Manager

Dana Brown Larsen has worked as a certified radiation therapist at a variety of medical colleges, hospitals, and radiation oncology clinics. She received her Bachelor of Science degree from the University of South Carolina and has been certified in both Radiology and Radiation Therapy by the American Registry of Radiologic Technologists.

Ms. Larsen began working for MPS as a consultant before joining us as the company’s project manager. In the latter capacity, Ms. Larsen is primarily responsible for coordinating logistics for all MPS’s commissioning projects.  Dana enjoys working with the customers to ensure that each project proceeds smoothly.