Analytical form of current-voltage characteristic of parallel-plane, cylindrical and spherical ionization chambers with homogeneous ionization

نویسندگان

چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Characterization of cylindrical ionization chambers for patient specific IMRT QA

Proven conventional dosimetry techniques do not provide accuracy and precision in the measurement of inverse planned intensity modulated radiation therapy (IMRT) fields. Dynamic and step-and-shoot multileaf collimation (DMLC/SMLC) challenge current ionization chamber dosimetry practices. Ionization chamber performance in these fields is evaluated for three cylindrical chambers of varying volume...

متن کامل

The calibration and use of plane-parallel ionization chambers for dosimetry of electron beams.

The AAPM TG 39 protocol has proposed three different methods of calibrating plane-parallel ionization chambers, i.e., in-phantom irradiation with a high-energy electron beam and in-phantom and in-air 60Co irradiation. To verify the consistency of the three methods, we have measured Ngaspp values using each of these techniques for the five most commonly used plane-parallel chambers considered by...

متن کامل

Measurement of ion recombination correction factors for plane parallel ionization chambers

The work presented focuses on the measurement of Ja e plots and determination of ion recombination factors for plane parallel ionisation chambers used in pulsed electron beams. The ability to measure the Ja e plots accurately is useful when commisioning a new chamber and the ion recombination correction factor needs to be known when the chamber is calibrated in a beam quality di erent from the ...

متن کامل

Monte Carlo calculations of correction factors for plane-parallel ionization chambers in clinical electron dosimetry.

Recent standard dosimetry protocols recommend that plane-parallel ionization chambers be used in the measurements of depth-dose distributions or the calibration of low-energy electron beams with beam quality R50 <4 g/cm2. In electron dosimetry protocols with the plane-parallel chambers, the wall correction factor, Pwall, in water is assumed to be unity and the replacement correction factor, Pre...

متن کامل

Measurements of output factors using different ionization chambers and build up caps

Background: The aim of this work was to study the output factors for Linac using different ionization chambers and build up caps. Materials and Methods: Output factors were measured for open square fields (3 × 3 cm to 40 × 40 cm) defined by collimator jaws for 6 and 15 MV photon beams from a Varian Clinac 2100C accelerator were measured. The measurements in air were performed using Com...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Journal of Instrumentation

سال: 2007

ISSN: 1748-0221

DOI: 10.1088/1748-0221/2/11/p11006