Physics - Beta Decay | Olly Britton

What are the two types of beta decay?

How should you write an electron in a beta decay equation?

\[_{-1}^0 e\]

When denoting particles in a beta decay equation, such as $ _ y^x \alpha$, what does $y$ represent?

The charge.

When denoting particles in a beta decay equation, such as $ _ y^x \alpha$, what does $x$ represent?

The nucleon number.

What two quantities are conserved in a beta decay equation?

What does the beta decay equation look like for beta-minus decay?

\[^1_0 n \to ^1_1 p + ^0_{-1} e + ^0_0 \bar{v}_e\]

Can you describe beta-minus decay in words?

A neutron decays into a proton and emits an electron.

What is true about the beta-minus particle (the electron) in a beta-decay equation that caused a problem historically?

It was emitted with a range of energies.

Why is a neutrino needed in a beta-decay equation?

Because otherwise energy is not fully conserved.

What is true about the “anti-ness” of the electron and the neutrino in beta decay?

They are opposite types, e.g. if an electron is emitted then an antielectron neutrino will be emitted.

What happens in terms of quarks for beta-minus decay?

A down quark decays into an up quark.

What does the quark transformation equation look like for beta-minus decay?

\[d \to u + ^0_{-1}e + ^0_0 \bar{v}_e\]

What force causes beta decay?

The weak nuclear force.

In beta-minus decay, is an electron or a positron emitted?

An electron.

In beta-plus decay, is an electron or a positron emitted?

A positron.

What does the beta decay equation look like for beta-plus decay?

\[_1^1p \to _1^0 n + ^0_{+1}e + ^0_0 v_e\]

What does the quark transformation equation look like for beta-plus decay?

\[u \to d + ^0_{+1}e + ^0_0 v_e\]

What happens in terms of quarks for beta-plus decay?

A up quark decays into a plus quark.

How can you remember which type of electron is emitted in beta-minus and beta-plus decay?

It’s like the minus or plus corresponds to $+1e$ or $-1e$ on the electron.

Physics - Beta Decay