title: Determination of virtual SSDs for electron beams from a dual energy linear accelerator.
abstract: Electron beams from an accelerator appear to originate from a point away from the vacuum window designated as virtual source. Virtual source to isocenter distances are determined experimentally by measurements in a polystyrene phantom with inverse square law method. Corrections required for percentage depth dose are also determined. Results of our study are compared with that of other investigators.
authors.affiliation: Kiwdai Memorial Institute of Oncology, Bangalore, India.
authors.forename: A K
authors.initials: AK
authors.lastname: Sharma
authors.forename: S S
authors.initials: SS
authors.lastname: Supe
authors.forename: V K
authors.initials: VK
authors.lastname: Narayanan
authors.forename: K
authors.initials: K
authors.lastname: Subbarangaiah
mesh_terms: D004583:Electrons; D006801:Humans; D016018:Least-Squares Analysis; D008961:Models, Structural; D010315:Particle Accelerators; D010347:Patient Care Planning / Q000379:methods* / Q000706:statistics & numerical data; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy / Q000379:methods* / Q000706:statistics & numerical data