1. Modern Observational/Instrumentation Techniques Astronomy 500
Andy Sheinis, Sterling 5520,
MW 2:30, 6515 Sterling
Office Hours: Tu 11-12

2. Class Website: Homework: Grading: HW 40% Project 20% Midterm 20%
Handouts, .ppt lectures and HW will be posted
Homework:
There will be a 5-6 problem sets, one due approximately every other week. I will either post, or handout solutions. I encourage you to discuss the problems with your classmates, but you must each write up your own solution.
There will also be a Midterm and Final exam as well as an “Observational” project, which may or may not include a laboratory exercise.
Grading:
Approximate grading distribution will be:
HW 40%
Project 20%
Midterm 20%
Final 20%

3. Texts:
Required:
Walker, "Astronomical Observations", Cambridge Univ. Press.
Schroeder, "Astronomical Optics", Academic Press
Recommended:
Kitchin, "Astrophysical Techiques", Adam Hilger, Ltd
Bevington&Robinson, "Data Reduction and Error Analysis for the Physical Sciences", McGraw-Hill
Gray, “The Observation and Analysis of Stellar Photospheres”, Cambridge U. Press
Other Useful References:
McLean, “Electronic Imaging in Astronomy”, Wiley
Rybicki and Lightman, “Radiative Processes in Astrophysics”, Wiley
Cox, “Allen’s Astrophysical Quantities”, Athlone Press

5. Astronomy is Different
Universe is the laboratory
We can only observe, no interaction
Limited to phenomena, occuring in the past
Must take interpret a “snapshot”
Have only the properties of light
Cannot measure directly, must infer from the measurement of light.

6. Properties of light Intensity, flux, irradiance, amplitude
Angle of arrival, position, image
Wavelength, frequency, color
Angular momentum, spin, polarization
time variation (in some cases)
Phase (interferometry, radio, AO)

7. LargeTelescopes Only two (Keck I and II) available in the 90’s
Several available at the turn of the century (the VLT units, Gemini North and South, Subaru, HET)
One more in 2005, SALT!
others under construction (LBT, GTC)
and plans already for m telescopes...

8. Telescopes Name Diameter Nationality of Sponsors Site Built
(SALT) m South Africa, USA, UK, Germany, Poland, New Zealand South African 2005
(GTC) m Spain Roque de los Muchachos Observatory, Canary Islands 2005
Keck m USA Mauna Kea Observatory, Hawaii
Keck m USA Mauna Kea Observatory, Hawaii
(HET) m USA, Germany McDonald Observatory, Texas
(LBT) 2x8.4 m USA, Italy, Germany Mount Graham Arizona
Subaru (NLT) 8.3 m Japan Mauna Kea Observatory, Hawaii
VLT 1 (Antu) 8.2 m ESO Countries (European + Chile) Paranal Observatory, Chile 1998
VLT 2 (Kueyen) 8.2 m ESO Countries (European + Chile) Paranal Observatory, Chile 1999
VLT 3 (Melipal) 8.2 m ESO Countries (European + Chile) Paranal Observatory, Chile 2000
VLT 4 (Yepun) 8.2 m ESO Countries (European + Chile) Paranal Observatory, Chile 2001
Gemini North 8.1 m USA, UK, Canada, Chile, Australia, Mauna Kea Observatory, Hawaii 1999
Gemini South 8.1 m USA, UK, Canada, Chile, Australia, Cerro Tololo Observatory, Chile 2001
(MMT) m USA Fred Lawrence Whipple Observatory, Arizona
Magellan m USA Las Campanas Observatory, Chile
Magellan m USA Las Campanas Observatory, Chile
BTA-6 6 m Russia Zelenchukskaya, Caucasus
Large Zenith Telescope (LZT) 6 m Canada, France Maple Ridge, British Columbia 2003
Hale Telescope 5 m USA Palomar Observatory, California

9. SALT Telescope
PIC: SALT outside now

11. WIYN Telescope

14. Total E/t= Luminosity, L
Total L is bolometric luminocity.
Should be able to derive lnew vs llambda using new=c/lambda
Ln = specific luminosity

15. Flux
L is a fundametally important quantity, but we cannot measure it on earth. Instead we measure flux.
Flux is energy incident on some area dA of the Earths surface. Flux is not conserved and falls of as R-2.

16. Flux Flux is measured in Janskys in the radio 1Jy=10-26 W m-2 Hz-1
In the visible flux is measured in apparent magnitudes

17. Flux: absolute magnitude
Absolute magnitude is the apparent magnitude that would be observed at 10 pc.
A is the total extinction due to intersetllar dust in magnitudes

18. For small changes in flux

19. Standard choices for reference flux
Vega system: apparent Magnitude of Vega = 0 in all bands.
Convenient, but non-physical
A-B magnitude system:
F0=3.63e10-23 W m-2 Hz-1, flat spectrum
Agrees with Vega at 548nm (center of V-band)

20. Interesting magnitudes (V-band)
Sun: m=-26.7
Full moon: m=-12.6
Sirius: m=-1.5
Naked eye limit: m=6
Brightest stars in Andromeda: m=19
Present day limit: m~29
Night sky: m=21.5 (best sites, dark time)
Night sky: m=18 (bright time)

21. Intensity Finite size source (subtends a real angle)
Specific intensity
Brightness, surface brightness
Specific brightness
Units: (Jy sr-1) or (W m-2 Hz-1sr -1) or (erg cm-2 Hz -1) or (m arcsec-2)
What happens when the source is not resolved?

22. Intensity Omega measured in RA and Dec v= frequency
Where I will depend on:
Omega measured in RA and Dec
v= frequency
t= Integration time
P=polarization
Location where you are receiving the light.

23. Observation E=energy received during measurement R=energy from the sky
F= filter function
Spectrometers try to make F as narrow as possible

24. 1.1µ silicon bandgap
3100Å is the UV atmospheric cutoff