Research Topics
| P J BiggsSummaryAffiliation: Massachusetts General Hospital Country: USA Publications
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Detail Information
Publications
Measurement of TVLs in lead for 4, 6 and 10 MV bremsstrahlung x-ray beams at scattering angles between 30 degrees and 135 degreesIris P Nogueira
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA
Health Phys 83:255-60. 2002..Monte Carlo calculations, performed at 4 MV to simulate the transmission of scattered radiation, are in good agreement with the experimental measurements...- Measurement of the leakage radiation from linear accelerators in the backward direction for 4, 6, 10, 15, and 18 MV x-ray energiesAdnan K Jaradat
Department of Physics, University of Massachusetts Lowell, One University Avenue, Lowell, MA 01854, USA
Health Phys 92:387-95. 2007..The average neutron leakage was less than 0.1% except for 18 MV, where neutron leakage was more than 0.1% of the useful beam at some positions... 
Do angles of obliquity apply to 30 degrees scattered radiation from megavoltage beams?Peter J Biggs
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
Health Phys 95:425-32. 2008..7 degrees +/- 4.0 degrees , and for the first two TVLs averaged 20.5 degrees +/- 5.8 degrees . There are no data in the NCRP reports for 30 degrees scattered radiation attenuated by steel with which to make a comparison...- Long term stability of a 50 kV X-ray unit for stereotactic irradiationPeter J Biggs
Radiation Oncology Department, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
J Appl Clin Med Phys 7:12-20. 2006..The IRM dropped steadily to about 96% to 97% of its initial value at 1000 days, but recovered to about 98% after that. Calibration prior to each procedure is strongly recommended... - Clinical physics, applicator choice, technique, and equipment for electron intraoperative radiation therapyPeter J Biggs
Department of Radiation Oncology, Massachusetts General Hospital, Fruit Street, Boston, MA 02114, USA
Surg Oncol Clin N Am 12:899-924. 2003..There are currently six new centers in the United States that practice IORT with a mobile linear accelerator and more than that in Europe... - Measurement of the collection efficiency of a large volume spherical ionization chamber in megavoltage therapy beamsP J Biggs
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA
Med Phys 26:2107-12. 1999..At isocenter, the comparable figures were 78% and 56% respectively for 4 MV and 65% and 38% respectively for 10 MV... - Distance-dose curve for a miniature x-ray tube for stereotactic radiosurgery using an optimized aperture with a parallel-plate ionization chamberP J Biggs
Department of Radiation Oncology, Massachusetts General Hospital, Boston 02114, USA
Med Phys 26:2550-4. 1999..5 mm with a dose variation of less than +/- 1%. For distances <7.5 mm, measurements made with a 1.5-mm-diam aperture agree better with those taken with a 1.7-mm-diam chamber compared with a 5.2-mm-diam chamber... - Evidence for a significantly higher than expected depth dependence of wedge transmission factors on the 4 MV beam of a new dual energy acceleratorP J Biggs
Department of Radiation Oncology, Massachusetts General Hospital, Boston 02114, USA
Med Phys 25:2234-6. 1998.... - Measurement of scatter factors for 4, 6, 10, and 23 MV x rays at scattering angles between 30 degrees and 135 degreesI P Nogueira
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA
Health Phys 81:330-40. 2001..The data show that, in general, the "a" factor decreases with energy; the exception is that 23 MV data show a sharp increase at low scattering angles, much greater than at other energies... - Tenth value layers for 60Co gamma rays and for 4, 6, 10, 15, and 18 MV x rays in concrete for beams of cone angles between 0 degrees and 14 degrees calculated by Monte Carlo simulationAdnan K Jaradat
Department of Physics, University of Massachusetts Lowell, One University Avenue, Lowell, MA 01854, USA
Health Phys 92:456-63. 2007..Energy spectra for 4, 6, 10, 15, and 18 MV x rays for 10 x 10 cm(2) and 40 x 40 cm(2) field sizes were used to generate depth dose curves in water that were compared with experimentally measured values... - Measurement of the neutron leakage from a dedicated intraoperative radiation therapy electron linear accelerator and a conventional linear accelerator for 9, 12, 15(16), and 18(20) MeV electron energiesAdnan K Jaradat
Department of Physics, University of Massachusetts Lowell, One University Avenue, Lowell, Massachusetts 01854, USA
Med Phys 35:1711-7. 2008..These neutron radiation levels are below regulatory values (National Council on Radiation Protection and Measurements, "Limitation of exposure to ionizing radiation," NCRP Report No. 116, NCRP Bethesda, MD, 1993)... - Intraoperative radiation therapy using mobile electron linear accelerators: report of AAPM Radiation Therapy Committee Task Group No. 72A Sam Beddar
Department of Radiation Physics, Division of Radiation Oncology, Unit 94, The University of Texas M D Anderson Cancer Center, Houston, Texas 77030, USA
Med Phys 33:1476-89. 2006.... - Review of the energy check of an electron-only linear accelerator over a 6 year period: sensitivity of the technique to energy shiftPeter J Biggs
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA
Med Phys 30:635-9. 2003..It is further shown that based on annual calibrations and RPC TLD checks, the energy of each beam is constant and that therefore the energy check is an exquisitely sensitive one. The consistency of the independent checks is demonstrated...