Observing with LBW for ALFALFA: Background Rules of the scavenger hunt:
1. Experienced observers shall not
reveal the answers to first timers until sufficient effort is
expended. (And, any bribes must be shared 50:50 with the Scavenger Hunt creators.)
2. You may consult any ALFALFA webpages
but please be sure to indicate where you got your information.
If you find any mis-information, make a note so we can correct the page.
Observing Parameters
Ob.0
How many monitors are at the observer's computer?
Ob.1
Find the monitor showing the Arecibo Status window. How do
you know where the Gregorian Dome is positioned at the moment? Where else
is this information listed?
Ob.2
What times are given on the last line of the Status window?
Ob.3
What are the tiedowns and are they active? What is the recommended
configuration of the tiedowns during UAT LBW observing?
Ob.4
Find the CIMA control windows.
What CIMA windows are visible and what do they tell you?
Ob.5
What is the scan number of an observation and what does the number sequence mean?
Ob.6
Observing is executed as a script. Briefly describe what the script is doing.
Ob.7
Are we using a topocentric or heliocentric
coordinate system tonight? What motions cause the difference?
What are the approximate heliocentric and geocentric corrections
at the moment?
Ob.8
What are "boards 1 & 2" and what are they recording? What are the frequency
range and width? How is the center of the bandpass determined?
Ob.9
How many scans are contained in a cor file? What is the purpose of
each scan? Why do we need all of them?
The Current Observation
Ob.10
What is the start LST of the current target?
Ob.11
What is the name and declination of the target?
Ob.12
What are the current azimuth and zenith angle of the telescope?
Ob.13
How do we check the pointing of the telescope?
Ob.14
What is the cor file name of the current observation?
Ob.15
Enter a line in the log. Write your entry here:
Monitoring the Data
While observing we monitor the data using an IDL script which runs several IDL programs created by Phil Perillat at Arecibo (you can find all his programs at Phil's idl page.) You may be familiar with these programs already from your work on Scavenger Hunt #1 .
Ob.16
Follow the Data Monitoring steps for LBW observations:
What script is run to view the spectra?
Read the more thorough directions and list what steps the script goes through to plot the spectrum:
What do you see plotted at the end? Do you see a source?
Ob.17
How many galaxies have been observed so far tonight?
Ob.18
How many galaxies have been detected so far tonight?
Ob.19
If your monitoring in Ques 16 did not show a detection, select
one of the detected galaxies and describe the appearance of the spectrum.
What is the central frequency and
width of the signal?
What velocity does this correspond to?
Are there peaks that do not correspond to the target?
What could these peaks be?
Ob.20
In what famous 1975 movie does the scientist say
to the character named Riff Raff "Well, see if you can find him on the MONITOR!"
Common Observing Problems
One of the ALFALFA Team's mottos is "Boring is good!" We always hope that observing will be
boring. However sometimes observing problems do occur and we want to be prepared to deal
with them quickly to minimize loss of observing time.
Ob.21
What happens if we get ahead/behind on
schedule? How will we know and what can we do?
Ob.22
What is the difference between aborting and stopping the command file?
Ob.23 Record any other tips
and tricks the advanced observer gives you. Also record any unusual
problems (we hope this will be a blank entry!)
Last modified: Mon Dec 30 11:36:16 EST 2013
by becky
