Efficiencies Database Interface

If you are at the JAC you may wish to use the perl/Tk based interface
which is available by typing 'efficiencies' at the command prompt.


Select Receiver:

Select source: Venus Mars Jupiter Saturn Uranus Neptune

Instructions:
Select the desired receiver, source and efficiency type.

Upon clicking 'Go' a new window will open in which a graph will be shown with all the matched observations. Note that it may take a little time for the graph axes to be draw (it is complete when the mouse stops showing a 'clock' symbol). This will also show the mean and various other basic statistics.

Within this window moving the mouse over any points in the graph will pop up basic information about the observation. Left clicking on the points will open up another window in which the spectra itself will be displayed (does not work yet for all spectra).

Also within the window with the graph of all matched points it is possible to press and hold the left mouse button (whilst not over the top of a point) and drag out a box (you must drag from top left to bottom right). Once the box has the desired shape left click within it and that area will be zoomed. If you get the shape of the box wrong click any where else in the graph and the box will be deleted, you can then try again. Within a zoomed graph right click anywhere to zoom back out.

Beam and aperture efficiency are derived from the average temperature in the spectra using the Starlink program fluxes which provides the expected planetary temperature for the date of observation. It assumes that the beamsize is equal to the theoretical beamsize at the observed frequency.

Notes (from fluxes):
The planetary brightness temperatures used are obtained from the measurements of Griffin et al. (1986, Icarus 65, 244), Orton et al. (1986, Icarus 67, 289), and Griffin & Orton (1993, Icarus, 105, 537). The errors in brightness temperatures are the rms internal errors of the observations. For MJD's between 46040 through 50000 the Martian temperatures are derived from the model developed by Wright (1976, Ap.J., 210, 250). Outside these MJD's (i.e., in particular after 10 October 1995) a simplified model of a rotating cratered asteroid is used (Wright, 1995; private communication to H.E. Matthews). Since the results for Mars are derived from models no errors are quoted; however the Martian brightness temperatures are probably uncertain at the 5% level and this uncertainty must be added to obtain the absolute errors. Over the interval for which both the original Wright model and the simplified model are valid, the differences in brightness temperatures have an rms error of 0.13 K (i.e. negligible). The flux densities for Saturn are for the planetary disk only; an additional flux is expected when the rings present an open aspect, and at such times Saturn should not be used as a calibration object. Individuals using these data in published works should reference the appropriate papers as noted above.