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Useful ALFALFA links

• Back to the Fall 2010 page
• Undergrad ALFALFA Getting Started page
• ALFALFA science links
• Intro to IDL for ALFALFA

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Introductory exercises

You will need to become familiar with Arecibo, the ALFA (the Arecibo L-band Feed Array) and ALFALFA (our survey) as well as the Sloan Digital Sky Survey and the GALEX satellite. So here are some links to other pages with some exercises that can help you get started. You don't have to do them all by tomorrow, but you should experiment with them over the next weeks.

• Questions about celestial coordinates, time and using Arecibo for ALFALFA
• Read about using ALFA for ALFALFA and do the exercises highlighted in red
• Read about the various online galaxy surveys and databases and try the Scavenger Hunt questions on that page
• Using SDSS, DSS2 and NED to find images/info of some interesting objects
• Check out our very own Cornell EGG HI digital archive
• Using NED to find the members of a rich cluster
• Using SDSS to find active galaxies in the cluster A1238
• Running a SDSS SQL query to find quasars with z > 5

Specific questions for Alex to consider

• What is the physics behind the 21 cm line emission that we detect with ALFALFA? What sources emit it? What is the temperature of the hydrogen?

• Read about the Sloan Digital Sky Survey (SDSS), the telescope that it uses and its separate imaging and spectroscopic components. What wavelength bands does the SDSS image? Why doesn't it get spectra for every object? Which objects does it get spectra of?

• Start up IDL and try to run PLOTALFA.

• Check out Carl H's IDL tutorials and experiment with the basics.

• Experiment with the quick intro to compiling IDL programs.

• Write an IDL program that computes the X,Y coordinates of points in a circle of arbitrary radius, and then plot them using IDL.

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Last modified: Mon Oct 4 17:48:25 EDT 2010 by martha