1. Physics of Astronomy- spring Dr. E.J. Zita, The Evergreen State College, 29.Mar.2004 Lab II Rm 2272, zita@evergreen.edu, 360-867-6853 http://academic.evergreen.edu/curricular/ PhyAstro/home.htm

2. Outline Logistics and time budget Special events & info Review of last quarter’s content Preview of spring quarter Introduction to Modern Astrophysics Ch.9 Spring weeks 1-2 Minilecture signup Astronomy signup

3. Logistics and time budget Seminar: Read, preseminar, and write (or rewrite) one paper per week. Research: Spend 12-16 hours per week carrying out your plan, reading, and doing calculations. Texts, classes, and homework: Please present in Astronomy & Cosmologies (AC) every other week Each team minilecture once per week in Physics of Astronomy (PA) (homework-focussed) NEW: P&Q (Points and questions) at least once a week in PA Total ~ 48-60 hours/week, so be sure to schedule in R&R, to stay healthy

4. Special events & info Spring Science Fair at Evergreen – you will definitely present a poster of your research there: May 28-29 (week 9) APS-NW = American Physical Society – Northwest Section meeting Moscow, Idaho / Pullman, WA 21-22 May (Fri.Sat end of week 8) Do you want to go? Present a poster of your research Deadline for registration and Abstracts: 23 April (week 4) Calculus tutorials with Matt (details TBA) TAs = Emily Himmelright and Jenni Walsh Office hours: Wednesday 5-6 in fishbowl

5. Review of winter quarter content

6. Intro to Modern Astrophysics Carroll and Ostlie = CO Basic astronomy  Gravity + orbits  Light + spectra  Modern physics, QM  Electromagnetism  Sun and Stars Thermal + radiation Cosmology

7. Physics and Astronomy Physics: What fundamental, quantitative principles explain the structure and evolution of the natural world? Astronomy: What do we see in the sky, and how do things move and change? Astrophysics: How can Physics explain what Astronomy observes?

8. Four realms of physics

9. Ch.1: The Celestial Sphere 1.1: The Greek Tradition; Team 1: Celestial Sphere 1.2 The Copernican Revolution; Team 2: Periods; prob.1.3 1.3 Positions on the Cel.Sph. Team 3.a: Altitude+ Azimuth (p.10-13), prob. 1.5 Team 3.b: Right Ascension and Declination (p.13-15), prob.1.4 Team 3.c: Precession and motion of the stars (p.15-19), prob.1.6 1.4 Physics and Astronomy (Figures from Freedman and Kaufmann, Universe)

10. Ch.1: Key concepts arclength D = d  when  is in radians Alt-Az above, RA-Dec below

11. Ch.2: Celestial Mechanics 2.1 Elliptical Orbits 2.2 Newtonian Mechanics: and conservation of angular momentum 2.3 Kepler’s Laws: we derived K3 from N2: 4  2 r 3 = GMT 2 We derived the Schwarzschild radius for a black hole; we weighed Jupiter and the Sun using orbital satellites, and we discovered dark matter in Galaxies from non-Keplerian velocity curves 2.4 The Virial Theorem: E = U/2 in a central field.

12. Keplerian orbits: closer = faster

13. Spherical coordinates

14. Ch.3: The continuous spectrum of Light 3.1 Parallax  distance  brightness 3.2 Magnitude 3.3 Wave nature of light 3.4 Radiation 3.5 Quantization of Energy 3.6 Color (wavelength)  temperature, power output, absolute brightness…

15. Spectra tell us all this about stars: Color  temperature: (m) = 3x10 -3 /T(K) Temperature  Power output per unit area: flux = intensity of radiation = F=  T 4 Power output = Luminosity = L Intensity = power / area: F= L/4  R 2 Greater radiation flux  brighter star: F ~ b Brightness is perceived on a logarithmic scale. Apparent magnitude difference m 2 -m 1 =  m= 1  brightness ratio b 1 /b 2 = 100 1/5 = 2.512 Absolute magnitude M is what a star would have if it stood at a distance of d=10 pc from Earth.

16. Ch.5: Interaction of Light & Matter 5.1 Spectral lines 5.2 Photons 5.3 Bohr model 5.4 QM and wave-particle duality

17. Spectral lines tell us more about stars: Spectral lines  composition & atmosphere, stellar type and age, Shifts in spectral lines  proper motion, rotation, magnetic fields (Zeeman), oscillations  internal structure, internal rotation, planets…

18. Emission and absorption lines text

19. Planck quantizes light energy: photons E = hc/ = h  pc Interference + diffraction: light = wave Photoelectric effect: Light particles (photons) each carry momentum p= hc/ (Giancoli Ch.38) Maxwell’s theory + Hertz’s experiment: EM waves

20. Modern Physics Plancks’s light quanta! explain the photoelectric effect (Einstein); supported by Compton effect; explain the H atom (Bohr) with deBroglie’s matter waves hf = K max + 

21. Bohr model DeBroglie: electrons as waves Planck: light as particles Derived H energies match observed spectra

22. Break time! then Spring syllabus:

23. Overview of Ch.9 Stellar Atmospheres 9.1: The radiation field 9.2: Stellar opacity 9.3: Radiative transfer 9.4: The structure of spectral lines

24. Spring weeks 1-2: HW & ML Astrophysics (Carroll & Ostlie) Ch.9 Astronomy (Freedman & Kaufmann) 19: The Nature of Stars 20: The Birth of Stars 21: Stellar Evolution 22: Deaths of stars Physics (Giancoli) 17: Thermal 19: Heat Mathematical Methods (Boas + Spiegel): review differentiation & integration with Matt in QRC Minilecture signup for Astro & Cosmo Supper time … then, Seminar in Lib 4004