Nuclear Techniques ›› 2016, Vol. 39 ›› Issue (6): 60203-060203.doi: 10.11889/j.0253-3219.2016.hjs.39.060203

• LOW ENERGY ACCELERATOR, RAY AND APPLICATIONS • Previous Articles     Next Articles

Beam spot size calculation and measurement of 6-MeV medical linear accelerator

LIAO Lang, SONG Ruiying, CHENG Peng   

  1. Shanghai United Imaging Healthcare Co., Ltd., Shanghai 201807, China
  • Received:2016-04-14 Revised:2016-05-04 Online:2016-06-10 Published:2016-06-12
  • Supported by:

    Supported by Zhangjiang National Innovation Demonstration Zone Special Development Fund (No.201505-JD-B108-010)


Background: The spot size is of interest to the beam quality for the accelerator facility. As compared with the large accelerator scientific facility, the method to calculate the spot size is found to be different in the medical linear accelerator. The spot size in medical linear accelerator determines the penumbra field of the dose, which is important for the effective operation of medical linear accelerator. Purpose: This paper aims to summarize the calculation methods of spot size, hence the discrepancy between both methods is investigated here to give a better understanding of the beam spot size. Methods: The experiment setup based on the optical detection technique was presented here to given rise to the spot size results of medical linear accelerator in Shanghai United Imaging Healthcare Co., Ltd. (UIH), and a combined non-Gaussian method was proposed here to give a suitable fitting for the experiment results. Results: The spot full width at half maximum (FWHM) of the 6-MeV medical linear accelerator was about 1.81 mm and 1.84 mm in x and y direction respectively, which is close to the results of calculation. Conclusion: The definition of the spot size proposed here is useful for the optimizing of accelerator design, as well as the penumbra field of dose.

Key words: Spot size, Gaussian fitting, Medical electron linear accelerator

CLC Number: 

  • TL53