What is Bethe-Bloch?
The Bethe formula or Bethe-Bloch formula describes the mean energy loss per distance travelled of swift charged particles (protons, alpha particles, atomic ions) traversing matter (or alternatively the stopping power of the material).
What is Bethe law?
As the electron passes through the equipotential surface AB, it experiences a force which alters its velocity. This is known as Bethe’s law of electron refraction.
What is minimum ionizing particle?
A minimum ionizing particle (MIP) is a particle whose mean energy loss rate through matter is close to the minimum. In many practical cases, relativistic particles (e.g., cosmic-ray muons) are minimum ionizing particles.
Is the Bethe formula the same as the Bloch formula?
On the other hand, in the 2008 Review of Particle Physics the formula was called “Bethe-Bloch equation”, even though Bloch’s expression (3) did not appear in the formula. But in more recent editions, the formula is now called the “Bethe formula”.
How does the Bethe formula work at low energy?
This can be seen by first replacing βc by v in eq. (1) and then neglecting β2 because of its small size. At low energy, the energy loss according to the Bethe formula therefore decreases approximately as v−2 with increasing energy.
When did Hans Bethe find the Bethe formula?
The non-relativistic version was found by Hans Bethe in 1930; the relativistic version (shown below) was found by him in 1932 (Sigmund 2006). The Bethe formula is sometimes called “Bethe-Bloch formula”, but this is misleading (see below). The relativistic version of the formula reads:
When does the Bethe formula reach a minimum?
At low energy, the energy loss according to the Bethe formula therefore decreases approximately as v−2 with increasing energy. It reaches a minimum for approximately E = 3 Mc2, where M is the mass of the particle (for protons, this would be about at 3000 MeV).