Dosimetry challenges on varian halcyon linac-simplified with autosetup of PTW beam scan

Varian Halcyon Linear Accelerator is the latest and advanced, fast treatment machine with 100% Image Guided treatment for all patients. The linear accelerator is designed like a Ring and is delivered pre-commissioned on the Varian Eclipse Planning System. Beam data measurements are required to ensure and verify the quality of the pre-commissioning data but these measurements are challenging for a physicist because there is no field light, no ODI and no laser on the Isocentre plane. The newly launched RFA, PTW BEAMSCAN, water tank was used for the first time in India to commission South East Asia's First Halcyon unit at Sterling Hospitals, Rajkot. The RFA has to be put on the couch top for measurements, so the couch tilt, tank level, water level, isocentre position is very difficult to align correctly. The Beam Scan RFA was used using the Autosetup for the Acceptance Testing and Commissioning of the Halcyon Linear Accelerator