Quark Basics
This elementary particle is a building block of protons and neutrons; only two of its six flavors appear in ordinary nuclei.
This is the quark composition of a proton.
This particle is the force carrier that binds quark together inside a nucleon.
What is a gluon?
This is the only fundamental force that can change a quark's flavor.
what is the weak nuclear force?
Nuclei with more than this many protons are radioactive.
What is 83?
This is the electric charge of an up quark.
What is +2/3 e?
This is the quark composition of a neutron.
What is udd?
This is the approximate range of the residual strong force between nucleons.
What is 1 to 2 femtometers?
In beta-minus decay, a neutron becomes this particle.
What is proton?
The Sun is only hot enough to make this element through nuclear fusion.
What is: Helium (He)?
This is the reason free quarks are never observed in nature.
What is color confinement?
This is the collective name for a proton or a neutron.
What is a nucleon?
This unit of length equals 10^-15 m and is used for nuclear-scale distances.
What is a femtometer (fm)?
This is the net nuclear change for beta-minus decay, using n, p, e-, and an antineutrion.
What is n to p plus an electron plus an antineutrino?
This force has infinite range, causes protons to repel one another, and helps set the maximum stable atomic number.
What is the electromagnetic force?
This is the electric charge of a down quark.
What is -1/3 e?
Add the three quark charges of a proton: +2/3 + +2/3 + -1/3. This is the net charge.
What is: +1?
This is the name for the level of the strong force that acts inside a single nucleon, binding quarks via gluons.
What is the color force?
At quark level in beta-minus decay, this quark changes into this other quark.
What is a down quark into an up quark?
This is the formation of new elements through nuclear fusion reactions inside stars.
What is: Nucleosynthesis?
In the Standard Model, this term describes a particle that is not made of anything smaller and has no detectable substructure.
What is an elementary particle?
A particle with quark content u u u would have this net charge, and it would not appear in ordinary matter.
What is: +2?
Extra neutrons help stabilize a large nucleus because they add attraction from the _____________ force without adding repulsion from the ___________ force.
What is: Strong Residual, Electromagnetic (EM)
The electron that appears in beta decay was not already inside the nucleus; it is created when this happens.
What is quark flavor change?
After this unit, chemists can treat the nucleus as this kind of core so they can focus on the electron cloud.
What is a known positive core?