the Radiosurgery Society®
Physics Committee

Jun Yang, Ph.D.  

Jun Yang Ph.D is chief physicist at the Philadelphia CyberKnife.  He is a member of the AAPM Task Group #135 and serves on the physics committee for the Radiosurgery Society. As an adjunct clinical associate professor of Drexel University, he has authored and co-authored many publications on medical physics with emphasis on Robotic Radiosurgery technology. Jun joined the Physics Committee in 2011 and as of January 2013 serves as the chairman.

Stanley H. Benedict, M.S., Ph.D. 

Dr. Stanley Benedict received an M.S. in Radiological Health Physics from San Diego State University, a Ph.D. in Biomedical Physics from UCLA, and diplomat in Radiological Therapeutic Physics from the American Board of Radiology. He has served as Chief of Clinical Physics at Virginia Commonwealth University and Director of Clinical Physics at the University of Virginia, and is currently Professor and Vice Chair of Clinical Physics in the Department of Radiation Oncology at the University of California at Davis, in Sacramento, California. His scholastic achievements include over 50 scientific peer-reviewed publications, a dozen book chapters and proceedings, and over 100 peer reviewed scientific abstracts for presentations at international symposia. Dr. Benedict has been PI, co-PI, co-investigator, and collaborator on a wide array of public and privately funded clinical medical physics research, including projects involving image guided radiation therapy, stereotactic radiosurgery, and radiation biology.

Dr. Benedict was the Chair of the AAPM Task Group 101 on Stereotactic Body Radiation Therapy, and is one of the editors of the recently released CRC Press book, Stereotactic Radiosurgery and Stereotactic Body Radiation Therapy (2014). Stan joined the Physics committee in August 2014.  

Ian Cowley, Ph.D. 

Ian graduated from Cambridge University with a degree in Natural Sciences in 2002.  He studied at Addenbrooke’s Hospital in Cambridge for a PhD on IMRT verification and improvement, awarded in 2006.  Since 2006, Ian has worked as a clinical radiotherapy physicist at the Harley Street Clinic in London, with experience in Siemens and Varian linacs, Varian Eclipse treatment planning, brachytherapy and Gamma Knife. In 2009, the Harley Street Clinic installed the first CyberKnife in the United Kingdom a project on which Ian oversaw the physics aspects.  Since 2009 Ian has been largely involve with CyberKnife unit, he joined the Physics Committee in 2011.

Christoph Fürweger, Ph.D.

Christoph joined the European CyberKnife Center in Munich, Germany in 2007 and is their chief medical physicist. In 2007 he received his Ph.D from the Atomic Institute of the Austrian Universities and the Medical University with his thesis, Thermoluminescence Dosemeters as Biologically Relevant Detectors. He was a guest researcher at the Heavy Ion Medical Accelerator facility (HIMAC), National Institute of Radiological Sciences (NIRS), Chiba, Japan and a research assistant at the Clinic for Radiotherapy and Radiobiology, Medical University of Vienna. His research areas of interest were in dosimetry and radiobiology in particle fields, cellular signaling, bystander effects. Along with be a member of the Radiosurgery Society (RSS), Christoph is member of the German Society for Medical Physics (DGMP), Austrian Organisation for Radiation Protection (OeVS), and the Alumni Organisation of Vienna Technical University.


Steve Goetsch, Ph.D.

Steve Goetsch is a clinical medical physicist in San Diego County, California.  He received his Ph.D. in Medical Physics from the University of Wisconsin Madison in 1983 and directed the Accredited Dosimetry Calibration Laboratory there for 7 years.  After 4 years at UCLA Medical Center he became Chief of Physics at the San Diego Gamma Knife Center and also works at Palomar Medical Center and the University of California San Diego Cancer Center in Chula Vista.  Steve is Chairman of AAPM Task Group 178 on Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance.   He is a member of AAPM, ASTRO, ISRS and the Health Physics Society.  Steve joined the RSS Physics Committee in March 2012. 


Per H. Halvorsen, M.S.

Per received his M.S. Radiological Medical Physics from the University of Kentucky in 1990. In service to the medical physics community, Mr. Halvorsen has consistently worked to promote better support and higher standards for clinical physicists working in small to medium sized community centers – serving as Chair of the Clinical Practice Committee, Chair of Task Groups 11 and 103 devoted to peer review in clinical radiation oncology physics, helping to initiate Task Group 127 to assist with physicists’ implementation of the ABR’s Maintenance of Certification program, as well as serving on the Board of Directors and as Chair of the Professional Council. Mr. Halvorsen has also been an active surveyor for the ACR’s Radiation Oncology accreditation program for many years, serving on the College’s accreditation committee for several years and helping to revise the accreditation program into its current format. He is currently Associate Editor for the open-access Journal of Applied Clinical Medical Physics. Mr. Halvorsen has 6 peer-reviewed manuscripts, 10 abstracts, and 1 book chapter. Per joined the RSS Physics Committee in January 2013.

Mary Ellen Masterson-McGary, M.A., M.S.

Mary-Ellen holds graduate degrees from Columbia University and from Cornell University. She has over 25 years of comprehensive experience in Radiation Oncology Physics, and over 15 years of experience in Stereotactic Radiosurgery. Before moving to Florida, Mary Ellen worked for 19 years as a member of the Department of Medical Physics at Memorial Sloan-Kettering Cancer Center in New York and held a faculty appointment at Cornell University Medical College. She has published and lectured widely on her clinical and research activities in radiological physics. She has served as a Chancellor and as the Chairman of the Board of Chancellors of the American College of Medical Physics. She has served as a Consulting Scientist to the National Council on Radiation Protection and Measurement. Mary Ellen was elected to serve three terms on the Board of Directors of the AAPM. She was elected President of the Radiological and Medical Physics Society of New York, and President of the Florida Chapter of the AAPM. We are very honored to say that Mary Ellen joined the RSS Physics Committee in 2011.

Timothy D. Solberg, M.S., Ph.D. 

Timothy Solberg received his master of science degree in physics from the University of California, Davis, and his PhD in biomedical physics from the University of California, Los Angeles (UCLA). His areas of specialization include radiation therapy physics, stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT), image-guided radiotherapy (IGRT), optimization and intensity-modulated radiotherapy, and radiation transport methods.

Dr. Solberg received his initial faculty appointment in the Department of Radiation Oncology at UCLA in 1996, and went on to hold the positions of professor, vice chair, and co-director of the Radiosurgery Program at UCLA. He was Director of Medical Physics and Barbara Crittenden Professor of Cancer Research in the Department of Radiation Oncology at the University of Texas Southwestern Medical Center in Dallas from 2008-2013. Dr. Solberg is currently a Professor and Director of the Division of Medical Physics in the Department of Radiation Oncology at University of Pennsylvania in Philadelphia, where he also holds the administrative position of Vice Chair. Dr. Solberg is actively involved in numerous professional societies, including the AAPM, ACR, ASTRO, ESTRO, and others. He is deputy editor-in-chief for the Journal of Applied Clinical Medical Physics, and reviews manuscripts for many other journals. He has authored over 150 papers, over 300 abstracts, 23 book chapters, 1 book (on stereotactic radiosurgery and SBRT), and given over 200 invited presentations. Dr. Solberg joined the RSS Physics Committee in August 2014.

Brian Wang, Ph.D.  

Brian received his Ph.D. in nuclear engineering from Rensselaer Polytechnic Institute (Troy, NY, USA) in 2005. He worked as a faculty medical physicist in the Department of Radiation Oncology at Cooper University Hospital from 2005 to 2007, where he received his clinical training. In 2007, he joined the University of Utah as an assistant professor where he specialized in LINAC-based stereotactic body radiotherapy (SBRT) and stereotactic radiosurgery (SRS). Currently, Brian is an associate professor and the Chief of Physics in the Department of Radiation Oncology at the University of Louisville. He’s serves as a Section Editor for the Journal of Applied Clinical Medical Physics and has been a guest Associate Editor for the Medical Physics Journal since 2005. In addition to RSS, Brian is a member of AAPM and ASTRO. He is also a committee member on several national committees and task groups. Brian joined the Physics Committee in 2012.

the Radiosurgery Society®
Physics Advisory Committee

C-M Charlie Ma, Ph.D.  

Dr. C-M Charlie Ma received his Ph.D. in medical physics from the University of London, London, UK in 1992. Dr. Ma continued his radiation therapy research and postdoctoral training at the Institute of Cancer Research and Royal Marsden Hospital, London, UK. He was a research officer at the National Research Council of Canada, Ottawa from 1993 to 1996, and an associate professor at Stanford University, Stanford, CA from 1996-2001. Currently, he is Professor, Director of Radiation Physics and Vice Chairman of the Department of Radiation Oncology at Fox Chase Cancer Center, Philadelphia, PA. Dr. Ma is specialized in Monte Carlo dose calculation, radiation dosimetry, image guidance, treatment optimization and delivery for intensity-modulated photon therapy, and energy- and intensity-modulated electron and proton beams for radiation therapy. He has edited 4 books and published more than 20 book chapters and 150 peer-reviewed journal articles in these areas.

Fang Fang Yin, Ph.D.

Dr. Yin received his Ph.D. in medical physics from the University of Chicago, Illinois in 1992. As the Chief of Radiation Physics in Radiation Oncology Department, Associate Director of Graduate Medical Physics Program, and Director of Radiation Oncology Physics Residency Program at Duke University School of Medicine, I have been actively engaged in education and training of medical physics graduate students and post-graduate clinical training. Dr. Yin has been actively engaged in the research of imaging and its application in radiation oncology for over 20 years. Major research efforts during the last 18 years have been related to imaging and image guidance in radiation therapy as well as in treatment planning and delivery optimization. He has published over 160 refereed papers and numerous book chapters and has been a member of several task group reports for the American Association of Physicists in Medicine.
Member login  

Renew for 2 years and save ~25%

the RSS would like to acknowledge and thank our Corporate Members.

Interact With Us!
facebook Like us on Facebook
twiter Follow us on Twitter 
Skype Me™!  Call us on Skype
Follow our Group on LinkedIn
(408) 385-9411 Give us a Call