The standard model

Question 1

define an elementary particle

Answer 1

a particle with no substructure, and thus not composed of other particles

Question 2

define an antiparticle

Answer 2

a particle that has the same mass and opposite charge and/or spin as a corresponding particle; e.g. positron and electron

Question 3

define gauge bosons

Answer 3

mediating particles that govern particle interaction and the mediation of the four fundamental forces.

Question 4

recall the four gauge bosons

Answer 4

1. photons - electromagnetic interaction
2. W bosons - weak interaction
3. Z bosons - weak interaction
4. gluons - strong interaction

Question 5

describe the strong nuclear force

Answer 5

binds quarks together to make subatomic particles such as protons and neutrons and underlies interactions between all particles containing quarks

Question 6

describe the weak nuclear force

Answer 6

all quarks and leptons experience this force, independent of electric charge. It is primarily responsible for radioactive decay and seems to control the energy-producing fusion reactions going on in stars

Question 7

describe the electromagnetic force

Answer 7

experienced by electrically charged objects such as all quarks and leptons with charge. Holds electrons in their atoms and binds matter together as molecules. Also causes protons to repel each other.

Question 8

describe gravitational force

Answer 8

one of the four fundamental forces but is yet to be incorporated into the standard model, all objects with mass experience the gravitational force

Question 9

define lepton

Answer 9

a class of elementary particle that respond only to the weak force and the gravitational force. They can carry one unit of electric charge or are neutral, and those that are charged experience the electromagnetic force.

Question 10

recall the 6 types of leptons

Answer 10

1. electron
2. muon
3. tau particles
4. electron neutrino
5. muon neutrino
6. tau neutrino

Question 11

define quarks

Answer 11

subatomic particles governed by the strong nuclear force that constitute hadrons

Question 12

recall the 6 types of quarks

Answer 12

up
down
charm
strange
top
bottom

Question 13

define baryon

Answer 13

composite subatomic particle made up of three quarks (or three antiquarks) held together by the strong nuclear force

Question 14

define meson

Answer 14

subatomic particle composed of one quake and one antiquark, held together by the strong nuclear force

Question 15

define lepton number

Answer 15

a conserved quantum number representing the difference between the number of leptons and the number of anti-leptons in an elementary particle reaction

Question 16

define baryon number

Answer 16

a quantum number defined by B=1/3(n-n)