2.2- PARTICLE SORTING Flashcards
How were the newly discovered particles created?
through high-energy interactions
What did the newly discovered particles decay into, apart from the neutrino?
into other particles and antiparticles
In what numbers were charged pions often produced in?
in pairs
As pions were produced in twos what did this lead to?
lead to the conclusion that π+ meson and π- meson are a particle-antiparticle pair
same conclusion for charged kaons
What is the antiparticle of charged pions?
charged pions are antiparticles of each other
How are particles and antiparticles divided?
divided into two groups called hadrons and leptons
How are particles and antiparticles separated between hadrons and leptons?
according to whether or not they interact through the strong interaction
What are hadrons?
particles and antiparticles that can interact through the strong interaction
What are examples of hadrons?
protons, neutrons, π mesons, K mesons
What are leptons?
particles and antiparticles that do not interact through the strong interaction
What are examples of leptons?
electrons, muons and neutrinos
How do leptons interact?
through:
weak interaction gravitational interaction electromagnetic interaction (if charged)
How do hadrons interact?
through all 4 fundamental interactions
through strong interaction and electromagnetic interaction if charged
Why do protons not decay?
they are stable
Through what interaction do hadrons tend to decay through?
weak interaction
What is the Large Hadron Collider?
ring-shaped accelerator that boosts the kinetic energy of charged particles in ring at several places round it
Why are there fixed magnets around the Large Hadron Collider?
they bend the path of the particles to keep them in the ring
What happens when particles in the Large Hadron Collider collide with other particles? (2) (equations)
total energy of particles + antiparticles before collision = their rest energy + their KE
total energy of particles + antiparticles after collision = their rest energy + their KE
What is the equation for conservation of energy?
rest energy of products = total energy before - KE of products
When kaons are created what may also be produced?
short-lived particles with greater rest masses than protons
How are the short-lived particles from when kaon are created, created?
through strong interactions
As the short-lived particles from the kaon creations are created through strong interactions, what are they?
hadrons
How are the short-lived particles different from kaons?
decay into protons and pions
Into what two groups can hadrons be divided into?
baryons and mesons
What are baryons?
protons and all other hadrons (including neutrons) that decay into protons either directly or indirectly
What are mesons?
hadrons that do not include protons in their decay products. In other words kaons and pions are not baryons
What are baryons and mesons composed of?
smaller particles called quarks and antiquarks
