Electrodynamics of paramagnetic neutron star
... Post-burst pulsed X-ray and gamma-ray emission of magnetars (SGR & AXP) is most likely powered by non-radial torsion oscillations of neutron stars ...
... Post-burst pulsed X-ray and gamma-ray emission of magnetars (SGR & AXP) is most likely powered by non-radial torsion oscillations of neutron stars ...
DETECTORS FOR IMAGING IN RADIATION THERAPY
... Abstract. Despite the many advances in patient positioning, dose deliverance as intended remains a difficult practical issue due to a number of complicating factors.Various techniques and methods have been developed over the years for accurate patient positioning.It has long been recognized that the ...
... Abstract. Despite the many advances in patient positioning, dose deliverance as intended remains a difficult practical issue due to a number of complicating factors.Various techniques and methods have been developed over the years for accurate patient positioning.It has long been recognized that the ...
Study the Quality Assurance of Conventional X
... 0.001. timer reproducibility was good and resulted normal reference radiation dose.Peak tube potential –kVp provides a measurement of the peak electrical potential across the Xray tube when it is operating. The X-ray tube kVp is most critical. A small error of this variable will have a greater effec ...
... 0.001. timer reproducibility was good and resulted normal reference radiation dose.Peak tube potential –kVp provides a measurement of the peak electrical potential across the Xray tube when it is operating. The X-ray tube kVp is most critical. A small error of this variable will have a greater effec ...
Technical Paper III - Radio Technology
... c) Under exposed d) Under developed 13. The X-ray beam used in diagnostic radiography can be described as: a) Homogenous b) Mono-energetic c) Poly-energetic d) Scattered 14. A recumbent position with the whole body tilted so that head is lower than the feet is called: a) Sim’s position b) Trendelenb ...
... c) Under exposed d) Under developed 13. The X-ray beam used in diagnostic radiography can be described as: a) Homogenous b) Mono-energetic c) Poly-energetic d) Scattered 14. A recumbent position with the whole body tilted so that head is lower than the feet is called: a) Sim’s position b) Trendelenb ...
The design and application of an in-laboratory
... however, the dependence upon these sources limits the applicability of these phase-related techniques—particularly for a clinical setting. Until now, the use of a conventional x-ray tube as the x-ray source for DEI and MIR imaging has been hindered as a result of the limited x-ray intensity and the ...
... however, the dependence upon these sources limits the applicability of these phase-related techniques—particularly for a clinical setting. Until now, the use of a conventional x-ray tube as the x-ray source for DEI and MIR imaging has been hindered as a result of the limited x-ray intensity and the ...
Radiographic Science
... Computed Tomography Technologists use a rotating x-ray unit to obtain "slices" of anatomy at different levels within the body. A computer then stacks and assembles the individual slices, creating a diagnostic image. With CT technology, physicians can view the inside of organs - a feat not possible w ...
... Computed Tomography Technologists use a rotating x-ray unit to obtain "slices" of anatomy at different levels within the body. A computer then stacks and assembles the individual slices, creating a diagnostic image. With CT technology, physicians can view the inside of organs - a feat not possible w ...
image receptors - Montgomery College
... Phosphor releases some visible light The x-ray energy is absorbed (trapped) Latent image Sensitive to a wide range of energies Erase plate if not used in 48 hours Process within an hour of exposure Increase mAs as CR is equivalent to 200 screen speed vs 400 screen speed used in film systems…why? ...
... Phosphor releases some visible light The x-ray energy is absorbed (trapped) Latent image Sensitive to a wide range of energies Erase plate if not used in 48 hours Process within an hour of exposure Increase mAs as CR is equivalent to 200 screen speed vs 400 screen speed used in film systems…why? ...
4. The X-Ray Tube
... A consequence of the line focus principle The beam intensity on the cathode side is more intense than on the anode side Patients must be positioned accordingly for some exams ...
... A consequence of the line focus principle The beam intensity on the cathode side is more intense than on the anode side Patients must be positioned accordingly for some exams ...
Screen Film Radiology
... relatively insensitive to x-rays, requires a lot of x-ray energy to produced a properly exposed x-ray film v Patient receives a large dose v To ...
... relatively insensitive to x-rays, requires a lot of x-ray energy to produced a properly exposed x-ray film v Patient receives a large dose v To ...
X-Ray Imaging
... • 1917: Johann Radon: mathema.cal framework. • 1963: Allan Cormack: tomographic image reconstruc.on, • 1972: Godfrey Hounsfield: first CT system, reconstruc.on. • 1979 Hounsfield & Cormack: Nobel Prize in Medi ...
... • 1917: Johann Radon: mathema.cal framework. • 1963: Allan Cormack: tomographic image reconstruc.on, • 1972: Godfrey Hounsfield: first CT system, reconstruc.on. • 1979 Hounsfield & Cormack: Nobel Prize in Medi ...
KUB RADIOGRAPHY REVISITED
... gastrointestinal diseases, which both produce abdominal pain • As a scout image for contrast study • Follow up procedure after the placement of devices such as ureteral stents,etc. ...
... gastrointestinal diseases, which both produce abdominal pain • As a scout image for contrast study • Follow up procedure after the placement of devices such as ureteral stents,etc. ...
New Technology in Radiation Oncology
... used either on (or in conjunction with) the linac on a daily basis. This calls for substantial investment in image acquisition and storage. X-ray tube and flat panel imagers provide stereo images for target localization in 3D space. You need to use digital techniques (instead of film) due to patient ...
... used either on (or in conjunction with) the linac on a daily basis. This calls for substantial investment in image acquisition and storage. X-ray tube and flat panel imagers provide stereo images for target localization in 3D space. You need to use digital techniques (instead of film) due to patient ...
File
... 800 detectors, single xray tube, rotate/rotate motion only, wide fan beam to cover the entire patient Scan time of newer scanners is about ½ s per slice Can produce ring artifacts ...
... 800 detectors, single xray tube, rotate/rotate motion only, wide fan beam to cover the entire patient Scan time of newer scanners is about ½ s per slice Can produce ring artifacts ...
Parham C, et al. Design and implementation of a compact low
... dependency than propagation-based imaging (8,14). Thus, DEI is able to provide images that have simultaneously higher contrast with lower dose compared to propagation-based phase-contrast imaging. Two other phase-contrast techniques are analogous to DEI in that they measure the first derivative of t ...
... dependency than propagation-based imaging (8,14). Thus, DEI is able to provide images that have simultaneously higher contrast with lower dose compared to propagation-based phase-contrast imaging. Two other phase-contrast techniques are analogous to DEI in that they measure the first derivative of t ...
Bruker-MicroCT method note: Limb positioning for in
... will be much noisier than that of the corresponding narrow object. A crossection including both hindlimbs and the rear torso / abdomen presents a vastly greater area and x-ray beam path length than the hindlimb held separately in a tube. Thus a single limb in a tube can be scanned to an acceptable i ...
... will be much noisier than that of the corresponding narrow object. A crossection including both hindlimbs and the rear torso / abdomen presents a vastly greater area and x-ray beam path length than the hindlimb held separately in a tube. Thus a single limb in a tube can be scanned to an acceptable i ...
Imaging Needs for Protons
... • Imaging serves to ensure the correct fraction dose • … and, in current practice, assumes geometry equals dosimetry. • True for g – Geometry does not affect dosimetry • False for p – Geometry strongly affects dosimetry • Not all observables are image-based • DGRT: Dose-Guided RT ...
... • Imaging serves to ensure the correct fraction dose • … and, in current practice, assumes geometry equals dosimetry. • True for g – Geometry does not affect dosimetry • False for p – Geometry strongly affects dosimetry • Not all observables are image-based • DGRT: Dose-Guided RT ...
Computed Tomography I
... represents the x-ray attenuation properties within the patient along a line between the x-ray focal spot and the point on the detector corresponding to the point on the image ...
... represents the x-ray attenuation properties within the patient along a line between the x-ray focal spot and the point on the detector corresponding to the point on the image ...
THE PHYSICS OF MED I CAL IMA G IN G
... of introduction, this is what we shall do here. Even so, a further difficulty arises. In a sense each variation on a theme is new and would certainly be so claimed by its originators, and yet it is not all these novelties that history requires us to remember. The passageof time act~ as a filter to p ...
... of introduction, this is what we shall do here. Even so, a further difficulty arises. In a sense each variation on a theme is new and would certainly be so claimed by its originators, and yet it is not all these novelties that history requires us to remember. The passageof time act~ as a filter to p ...
A Versatile Tool to Study Biological Macromolecules in Solution
... SAXS: A Versatile Tool to Study Biological Macromolecules in Solution The Biophysics Collaborative Access Team (BioCAT), which operates the high-brilliance undulator Beamline 18ID at the Advanced Photon Source, Argonne National Laboratory, is dedicated to studying biological macromolecules in soluti ...
... SAXS: A Versatile Tool to Study Biological Macromolecules in Solution The Biophysics Collaborative Access Team (BioCAT), which operates the high-brilliance undulator Beamline 18ID at the Advanced Photon Source, Argonne National Laboratory, is dedicated to studying biological macromolecules in soluti ...
X-ray Source for XPS New Model CTX400
... The CTX400 X-ray source has twin anodes with independent filaments to provide two separate excitation energies for X-ray Photoelectron Spectroscopy. Usually supplied with Mg/Al anodes but other combinations are also available and it is easy to fit replacement anodes with different coatings. The X-ra ...
... The CTX400 X-ray source has twin anodes with independent filaments to provide two separate excitation energies for X-ray Photoelectron Spectroscopy. Usually supplied with Mg/Al anodes but other combinations are also available and it is easy to fit replacement anodes with different coatings. The X-ra ...
Computed Tomography
... 2 mSv, of the thorax 10 mSv and of the abdomen 15 mSv. This is a factor 10 to 100 higher than radiographic images of the same region, but the diagnostic content of the CT images is typically much higher. Some scanners use a lower tube current and a higher voltage to reduce the dose. However, there i ...
... 2 mSv, of the thorax 10 mSv and of the abdomen 15 mSv. This is a factor 10 to 100 higher than radiographic images of the same region, but the diagnostic content of the CT images is typically much higher. Some scanners use a lower tube current and a higher voltage to reduce the dose. However, there i ...
CTbushong2
... Patient dose may be somewhat higher with fourth-generation scanners because of interspace between detectors When there is an interspace between detectors, some x-radiation falls on the interspace, resulting in a wasted dose As the fan beam passes across each detector, an image projection is acqu ...
... Patient dose may be somewhat higher with fourth-generation scanners because of interspace between detectors When there is an interspace between detectors, some x-radiation falls on the interspace, resulting in a wasted dose As the fan beam passes across each detector, an image projection is acqu ...
exposurefactors
... proportional to the square of the distance from the source of radiation. – When the distance is doubled, the beam is one quarter as intense. – When the distance is halved, the beam is four times more intense. ...
... proportional to the square of the distance from the source of radiation. – When the distance is doubled, the beam is one quarter as intense. – When the distance is halved, the beam is four times more intense. ...
Refresher Training for X-Ray Equipment Operators
... – Digital resulted in good images without changing factors, even if patient dose was higher, so factors were not optimized to lower dose. – Also, techniques were used to reduce signal noise that resulted in increased dose. ...
... – Digital resulted in good images without changing factors, even if patient dose was higher, so factors were not optimized to lower dose. – Also, techniques were used to reduce signal noise that resulted in increased dose. ...
X-ray
X-radiation (composed of X-rays) is a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning Röntgen radiation, after Wilhelm Röntgen, who is usually credited as its discoverer, and who had named it X-radiation to signify an unknown type of radiation. Spelling of X-ray(s) in the English language includes the variants x-ray(s), xray(s) and X ray(s).X-rays with photon energies above 5–10 keV (below 0.2–0.1 nm wavelength) are called hard X-rays, while those with lower energy are called soft X-rays. Due to their penetrating ability, hard X-rays are widely used to image the inside of objects, e.g., in medical radiography and airport security. As a result, the term X-ray is metonymically used to refer to a radiographic image produced using this method, in addition to the method itself. Since the wavelengths of hard X-rays are similar to the size of atoms they are also useful for determining crystal structures by X-ray crystallography. By contrast, soft X-rays are easily absorbed in air and the attenuation length of 600 eV (~2 nm) X-rays in water is less than 1 micrometer.There is no universal consensus for a definition distinguishing between X-rays and gamma rays. One common practice is to distinguish between the two types of radiation based on their source: X-rays are emitted by electrons, while gamma rays are emitted by the atomic nucleus. This definition has several problems; other processes also can generate these high energy photons, or sometimes the method of generation is not known. One common alternative is to distinguish X- and gamma radiation on the basis of wavelength (or equivalently, frequency or photon energy), with radiation shorter than some arbitrary wavelength, such as 10−11 m (0.1 Å), defined as gamma radiation.This criterion assigns a photon to an unambiguous category, but is only possible if wavelength is known. (Some measurement techniques do not distinguish between detected wavelengths.) However, these two definitions often coincide since the electromagnetic radiation emitted by X-ray tubes generally has a longer wavelength and lower photon energy than the radiation emitted by radioactive nuclei.Occasionally, one term or the other is used in specific contexts due to historical precedent, based on measurement (detection) technique, or based on their intended use rather than their wavelength or source.Thus, gamma-rays generated for medical and industrial uses, for example radiotherapy, in the ranges of 6–20 MeV, can in this context also be referred to as X-rays.