Quarks and Leptons - 2 Flashcards
What are cosmic rays?
high energy particles that move through space
what happens when cosmic rays enter the atmosphere?
these create short lived particles and antiparticles and photons
how are pions and kaons made/
in pairs through the strong interaction
how must kaons decay?
via the weak interaction
are kaons strange?
yes
what can a kaon decay into?
pions, muon and antineutrino, antimuon and neutrino
what does a pie 0 decay into
high energy photons
what does a charged pion decay into?
muon and antineutrino, antimuon and neutrino
what does a muon decay into?
electron and antineutrino
what does an antimuon decay into?
positron and neutrino
what interactions can leptons do ?
weak, gravitational, electromagnetic
what interactions can hadrons do?
strong, weak, gravitational, electromagnetic, mostly weak
rest energy =
total energy before - ke of products
what are the two categories of matter and antimatter
hadrons and leptons
what are the two categories of hadrons
baryons and mesons
difference between baryons and mesons?
mesons have no protons in their decay
do leptons have quarks
no
do hadrons have quarks
yes
what are mesons made from
quark and antiquark
what are baryons made from
three quarks
is the lepton number always conserved
yes
name a strange particle?
kaon
how do you calculate the energy of a photon
E=Hf
which fundamental interaction is responsible for electron capture?
weak interaction - w- boson is the mediator
what is the quark structure of a proton
uud
what is the quark structure of a neutron
udd
what is the exchange particle for the strong nuclear force?
pion
what is the exchange particle for the weak nuclear force?
w bosons
how does the strong nuclear force maintain stability?
keeps an equilibrium distance
what is the strangeness of an anti strange quark?
1
when is strangeness conserved?
in strong interactions but not weak
