{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

lecture04 - Astronomy Picture of the Day Gliese 581...

Info iconThis preview shows pages 1–15. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Astronomy Picture of the Day Gliese 581 exoplanet (artist’s impression) 1 2 3 4 A simple model of atomic structure • Electrons have discrete energy levels in an atom • The electron can only be on these energy levels, not in between • Outer orbits have greater energy than inner orbits 1 2 3 4 1 2 3 4 Transitions between energy levels • The photon can only be absorbed if its energy (E = h ν ) is equal to the difference in energy between two energy levels • In this case, E(photon) = h ν = E 2- E 1 1 2 3 4 1 2 3 4 Transitions between energy levels • The energy of the photon is equal to the energy difference between the two energy levels • In this case, E(photon) = h ν = E 3- E 1 1 2 3 4 Transitions between energy levels • An electron in a high energy level can jump to the ground level all at once, or cascade downward in a series of steps through different energy levels 1 2 3 4 Transitions between energy levels • An electron in a high energy level can jump to the ground level all at once, or cascade downward in a series of steps through different energy levels 1 2 3 4 Transitions between energy levels • An electron in a high energy level can jump to the ground level all at once, or cascade downward in a series of steps through different energy levels 1 2 3 4 Transitions between energy levels • An electron in a high energy level can jump to the ground level all at once, or cascade downward in a series of steps through different energy levels 1 2 3 4 Ionization of an atom by a photon • If the photon’s energy is large enough, it can kick the electron out of the atom altogether • An atom missing one or more electrons is called an ion 1 2 3 4 Ionization of an atom by a photon • If the photon’s energy is large enough, it can kick the electron out of the atom altogether • An atom missing one or more electrons is called an ion 1 2 3 4 Collisional Excitation • In a collision between an atom and a free electron, the atom can absorb some of the collision energy by raising a bound electron to a higher energy level 1 2 3 4 Collisional Excitation • In a collision between an atom and a free electron, the atom can absorb some of the collision energy by raising a bound electron to a higher energy level Recombination 1 2 3 4 • Recombination: when a free electron becomes bound to an atom (it re-combines with an ion to make an atom) • The electron gives up its energy by emitting a photon Recombination 1 2 3 4 • Recombination: when a free electron becomes bound to an atom (it re-combines with an ion to make an atom) • The electron gives up its energy by emitting a photon Recombination...
View Full Document

{[ snackBarMessage ]}

Page1 / 58

lecture04 - Astronomy Picture of the Day Gliese 581...

This preview shows document pages 1 - 15. Sign up to view the full document.

View Full Document Right Arrow Icon bookmark
Ask a homework question - tutors are online