Precise Pointing and Focus Tests

Once again, here the idea is to pick bright point sources and do a next order job of figuring out SPARO's pointing and focus.

The following table has information for some bright sources, including integration times for a S/N of 10, which should be good enough for pointing and focusing. In some cases a range of temperatures is given, in which case a corresponding range of peak fluxes and integration times will also be given. Coordinates are for the 2000 equinox. In all cases, the approximate angular size for the following objects is 5'. This is fine for pointing, but not quite ideal for focusing. Also, we have noted when information at various wavelengths is available to confirm that the peaks' positions are wavelength-independent from 100 microns to 450 microns.

Source	RA	Dec	Temperature	Peak intensity	Angular Size	t₁₀	Notes
NGC 6334	17 20 55.0	-35 46 05.7	20-30 K	1400 MJy/sr	3'	8.4 s	Coordinates given for the northern peak. Submillimeter maps are available and were used to confirm the IRAS peak position. NGC 6334 I is our best bet for focusing.
RCW 122	17 20 05	-38 57 48	35-60 K	740-260 MJy/sr	5'	23-183 s	Coordinates are for a 150 micron peak, which is about 30" from the peak taken from the IRAS 100 micron FITS file.
RCW 108	16 40 00	-48 51 45	35-40 K	460-330 MJy/sr	5'	26-50 s	Coordinates are for a 150 micron peak, which is within 7" of the IRAS 100 micron peak.
RCW 57	11 11 49	-61 18 43	40 K	715 MJy/sr	6.5'	6 s	Coordinates are from 150 micron and 1 mm data, which agree well. The IRAS 100 micron FITS file peak agrees well with these coordinates. The skyview search give coordinates that are 3/4 of a degree off, but these coordinates are now believed to belong to a nearby source, NGC 3603.
RCW 36	08 59 00.9	-43 44 10	40 K	315 MJy/sr	6'	81 s	Coordinates are for a 150 micron peak, which agree well with the peak from the IRAS 100 micron FITS file.
Sgr B2	17 47 21	-28 23 00	-	at least as bright as 6334	at least as big as 6334	-	coords are from Dave Chuss' thesis (he smoothed a submm map to see where peak would be seen by SPARO)

The zenith optical depth was assumed to be 1.5 in all cases. The peak 450 micron intensities were based on an emissivity of wavelength to the -1.5 power and a known 100 micron intensity from IRAS FITS files.