Electron capture

This process happens for nuclei which have a high ratio of protons compared to neutrons. (They call it a superabundance of protons).

• An electron from the inner electron level is absorbed by the nucleus and interacts with a proton.
• The proton becomes a neutron by changing a u quark to a d quark, and a neutrino is released.
• This must be a WEAK interaction because there is a change of quark flavour.
• It is also called K-capture because the electron that is captured is said to have been in the K orbital.

Link to AQA website for markschemes

Here's the link to the AQA website: http://www.aqa.org.uk/qualifications/a-level/science/physics-a/physics-a-key-materials

Choose the "Past papers and mark schemes".  Then there's a drop down box to choose the year.  We are studying PHYA2 at the moment.  The resits are PHYA1.