As in Stereotactic Body Radiation Therapy, used to kill the cancer cells in small-ish tumors. It's a pretty amazing application of technology, designed to deliver pretty lethal doses of radiation to the tumors themselves while delivering less-than-lethal doses to surrounding tissues, as little as mm away.
The heart of the various machines (there are at least two manufacturers with big market share) is a lineac, a linear accelerator (of electrons). In striking a target inside the machine, the electrons produce a quite narrow beam of photons.
But what is the wavelength of those photons?
Some sources say it's "x-rays", some that it's gamma radiation. But no source that I've been able to find says what the wavelength (or, more likely, wavelength range) acutally is! :jaw-dropp
Yes, you can find the radiation dosage (in greys), and even mention of energies (of the beam), in kV and (sometimes) MV.
To be clear, there is no precise definition of the boundary between x-rays and gammas, and different branches of physics (and related fields, e.g. astronomy) seem to use different definitions. But in all you can fairly easily get values for the wavelength(s) being studied (OK, the units are not all that friendly; Angstroms (0.1nm, a unit of distance) and keV/MeV (a unit of energy) are both used, but at least there's no trouble converting them).
Maybe you, dear reader, have better DDG-foo than I have?
The heart of the various machines (there are at least two manufacturers with big market share) is a lineac, a linear accelerator (of electrons). In striking a target inside the machine, the electrons produce a quite narrow beam of photons.
But what is the wavelength of those photons?
Some sources say it's "x-rays", some that it's gamma radiation. But no source that I've been able to find says what the wavelength (or, more likely, wavelength range) acutally is! :jaw-dropp
Yes, you can find the radiation dosage (in greys), and even mention of energies (of the beam), in kV and (sometimes) MV.
To be clear, there is no precise definition of the boundary between x-rays and gammas, and different branches of physics (and related fields, e.g. astronomy) seem to use different definitions. But in all you can fairly easily get values for the wavelength(s) being studied (OK, the units are not all that friendly; Angstroms (0.1nm, a unit of distance) and keV/MeV (a unit of energy) are both used, but at least there's no trouble converting them).
Maybe you, dear reader, have better DDG-foo than I have?
via International Skeptics Forum https://ift.tt/2MtkSPX
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