γ is the Greek letter gamma. Those are γ-rays, not y-rays.
So why are X-rays the only ones that are just X if the rest are Greek
In an 1895 paper, Röntgen used "X" to label an unknown type of radiation. And the name stuck, despite his later objections. (Some languages do call them Röntgen rays.)
German for example does this.
Ix-Strahlung certainly doesn't roll off the tongue.
γ is the Greek letter gamma. Those are γ-rays, not y-rays.
So why are X-rays the only ones that are just X if the rest are Greek
In an 1895 paper, Röntgen used "X" to label an unknown type of radiation. And the name stuck, despite his later objections. (Some languages do call them Röntgen rays.)
German for example does this.
Ix-Strahlung certainly doesn't roll off the tongue.
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