Where did all the Elements come from?

Nucleogenesis and Fusion of Subatomic Particles

Reviewing the Beginning13.7 billion years ago

Extremely hot

Expanding “soup of particles”

Inflation: early phase rapid expansion

Cooling with steady, constant expansion

Nuclear Weak Force

Nuclear Strong Force

Cosmic Background Microwave Radiation

Baryons: Protons & Neutrons Made up of quarks

Fusion of nuclei Hydrogen (makes up 90% of the Universe today) Helium Lithium Beryllium

No electrons attached to these nuclei Too hot

The Nuclear Weak ForceThe Weak Force is responsible

for Initiating hydrogen fusion in

stars the radioactive decay of

subatomic particles

o Large nuclei are unstable

o Neutron = proton + electron

o β-decay: Neutrons fall apart to form a proton and an electron, the electron escaping

Nuclear Strong ForceProtons are all positive and would love to repel each

other

The nuclear strong force holds the nucleus together You must have energy to exert a force. Nuclear energy powers the strong force.

Affects very small space

HUGE amount of energy – released in fission…bombs

Nuclear Strong Force: Squeezing a Nerf Ball

Imagine squeezing a nerf ball The ball wants to expand

to its original shape It cannot because the force

of your hand is too great.

The nuclear strong force is like an invisible hand that holds the nucleus (Nerf ball) together.

Without it, there could only be Hydrogen in the Universe

FusionProton-Proton Chain

2 Hydrogen fuse to form Helium Helium fuse to form Carbon Carbon fuses with Hydrogen to form Nitrogen Nitrogen fuses with Hydrogen to form Oxygen…..

Requirements of FusionHeat-Heat-Heat

Gravity pulls the atoms together

Gravitational pressure heats the gases to millions of degrees

Mass - Stars: the bigger they are the hotter they are More Mass = More heat

= more fusion = more elements

IronFusion in stars can form nuclei that have up to 26

protons = IRON Too much energy is required to overcome the

electromagnetic repulsion

• Creating elements heavier that iron requires more energy

Fusion also Creates NeutronsNeutrons – captured by other atoms to form

Isotopes Isotopes are forms of standard elements with extra

neutrons

The Heavier ElementsSupernova of extremely massive stars

Cores of these stars are saturated with iron Extreme pressure and temperature

Gamma radiation breaks the iron nuclei releasing more energy

Shock-wave produces enough energy to fuse elements heavier than iron up to and including Uranium