Serafim  Papadimitriou

Chang Ming Charlie Ma

Professor & Vice Chair


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 until 1993. 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 to 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 180 peer-reviewed journal articles in these areas.


Area of Interest

Radiation dosimetry, Monte Carlo simulation technique, radiation oncology, radiation physics, radiation biology, high-intensity focused ultrasound, radio-dynamic therapy, intensity modulated radiotherapy (IGRT), image guided radiotherapy (IGRT), particle therapy

top publication

(Peer-reviewed Papers)
1. C.-M. Ma, A new way to ascertain conjugate vectors - the parallel optimization method, J. of East China Univ. of Technology, 5-1 (1985) 89-97 (in Chinese with English abstract)
2. C.-M. Ma and X.Q. Dai, Subdivision of laser interferometric signals using microcomputers, Proc. 2nd National Conference on Precision Mechanical System and Its Element Designing, Shanghai China (1986) 156-177 (in Chinese)
3. C.-M. Ma, W.M. Cheng and S.L. Zhuang, Imaging of phase contrast microscopes under partially coherent illumination, Acta Optica Sinica, 6 (1986) 129-36 (in Chinese with English abstract)
4. C.-M. Ma and X.Q. Dai, Relation of Moire fringe contrast with the black-to-white ratio of Gratings, Meters and Instruments, (1986) 4:151-159 (in Chinese)
5. C.-M. Ma and S.L. Zhuang, Noise performance of temporally partial coherent signal processors Pt. II Acta Optics Sinica, 7 (1987) 385-393 (in Chinese with English abstract)
6. C.-M. Ma and X.Q. Dai, Multi-circular grating ruling and short-periodic position error, Meters and Instruments, (1987) 5:212-218 (in Chinese)
7. C.-M. Ma and X.Q. Dai, Effect of Grating Positional Error on Moire Signal Contrast, SPIE 1012 In-Process Optical Measurements (1988) 99-106.
8. C.-M. Ma and R. Smith, Theoretical and Experimental Research on Super-resolution of Microscopes: 1. Illumination and Resolving Power, SPIE Scanning Imaging (1988) 1028: 45- 52.
9. C.-M. Ma and T.H. Dong, Effect of Ametropia on Laser Interferometric Visual Acuity, SPIE Optical Design Methods, Applications and Large Optics (1988) 1013: 128-134.
10. C.-M. Ma and A.E. Nahum, Bragg-Gray theory and ion chamber dosimetry in photon beams, Phys. Med. Biol. (1991) 36: 413 – 428
11. C.-M. Ma and A.E. Nahum, A new algorithm for EGS4 low-energy electron transport to account for the change in electron discrete interaction cross-section with energy, Nucl. Instr. Meth. B72 (1992) 319 - 30
12. C.-M. Ma, D.W.O. Rogers, K.R. Shortt, C.K. Ross, A.E. Nahum and A.P. Bielajew, Wall Correction and Absorbed Dose Conversion Factors for Fricke Dosimetry: Monte Carlo Calculations and Measurements, Med. Phys. (1993) 20: 283 - 93
13. C.-M. Ma and A.E. Nahum, Effect of size and composition of central electrode on the response of cylindrical ionization chamber in high energy photon and electron beams. Phys. Med. Biol. (1993) 38: 267 - 93
14. C.-M. Ma and A.E. Nahum, Calculation of absorbed dose ratios using correlated Monte Carlo sampling, Med. Phys. (1993) 20: 1189 - 99
15. C.-M. Ma and A.E. Nahum, Correction factors for Fricke dosimetry in high-energy electron beams, Phys. Med. Biol. (1993) 38: 423 - 38
16. C.-M. Ma and A.E. Nahum, Dose conversion and wall correction factors for Fricke dosimetry in high-energy photon beams: analytical model and Monte Carlo calculations, Phys. Med. Biol. (1993) 38: 93 - 114
17. C.-M. Ma and A.E. Nahum, Monte Carlo calculated correction factors for a NE2571 chamber in medium-energy x-ray beams, Measurement Assurance in Dosimetry, IAEA-SM-330/5, Vienna (1994) 371 - 382
18. C.-M. Ma and A.E. Nahum, Theoretical and experimental investigation of the prototype NPL design of plane-parallel chambers, Measurement Assurance in Dosimetry, IAEA-SM-330/4, Vienna (1994) 495 - 504
19. C.-M. Ma and A.E. Nahum, Plane-parallel chambers in electron beams: Monte Carlo findings on perturbation correction factor, Measurement Assurance in Dosimetry, IAEA-SM-330/71, Vienna (1994) 481 – 93
20. C.-M. Ma, Implementation of a Monte Carlo radiation transport code on a parallel computer system Parallel Computing (1994) 20: 991 - l005
21. C.-M. Ma, R. Knight, A.E. Nahum and P, Mayles, Measurement of Ce factors for the NPL prototype plane-parallel chamber, Phys. Med. Biol. 39 (1994) 1593 - 608
22. C.-M. Ma and A.E. Nahum, Monte Carlo Calculated ion chamber stem effect corrections for medium-energy x-ray dosimetry, Phys. Med. Biol. (1995) 40: 63-72
23. C.-M. Ma and A.E. Nahum, Calculations of ion chamber displacement corrections for medium energy x-ray dosimetry, Phys. Med. Biol. (1995) 40: 45-62
24. D.W.O. Rogers, B.A. Faddegon, G.X.Ding, C.-M. Ma, J.S. Wei and T.R. Mackie, BEAM: A Monte Carlo code to simulate radiotherapy treatment units, Med. Phys. (1995) 22: 503-25
25. J.L. Chartier, B. Grosswendt, G.F. Gualdrini, H. Hirayama, C.-M. Ma, F. Padoani, N. Petoussi, S.M. Seltzer and M. Terrissol, Reference fluence-to-dose-equivalent conversion coefficients and angular-dependence factors for 4-element ICRU tissue, water and PMMA slab phantoms irradiated by broad electron beams, Radiat. Protection Dosim. (1996) 63: 7-14
26. X.A. Li, C.-M. Ma and D. Salhani, Measurement of percentage depth dose and lateral beam profile for kilovoltage x-ray therapy beams, Phys. Med. Biol. (1997) 24; 2561-8
27. C.-M. Ma and J.P. Seuntjens, Correction factors for waterproofing sleeves in kilovoltage x-ray beams, Med. Phys. (1997) 24; 1507-1513
28. C.-M. Ma, B. A. Faddegon, D.W.O. Rogers and T. R. Mackie, Accurate characterization of Monte-Carlo calculated electron beams for radiotherapy, Med. Phys. (1997) 24: 401-416
29. X.A. Li, D. Salhani and C.-M. Ma, Characteristics of orthovoltage x-ray therapy beams at extended SSD for applicators with end plates, Phys. Med. Biol. (1997) 42: 357-70
30. L. Ma, A.L. Boyer, L. Xing, C.-M. Ma, An optimized leaf setting algorithm for beam intensity modulation using dynamic multileaf collimators, Phys. Med. Biol. (1998) 43:1629-43