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4.8 GHz / 6 cm Spectroscopy with the 26m telescope

Table 1. 4.8 GHz / 6 cm Receiver characteristics. PSS and SEFD for each sense of polarized radiation
Receiver type dual cryogenic HEMTs
Polarization LCP+RCP
RF filter 4610-5014 MHz
Zenith System temperature 55 K
Point Source Sensitivity 6.0 Jy/K/Pol
System Equivalent Flux Density 650 Jy
Half Power Beamwidth 0.160 degrees

Table 2. Lines observable at 4.8 GHz
Spectral Line Rest Frequency (MHz)
hydroxyl 4765.562
hydroxyl 4750.656
hydroxyl 4660.242
formaldehyde 4829.65971
H109alpha 5008.924
H110alpha 4874.157
H111alpha 4744.183
H112alpha 4618.791

Table 3. Velocity range, spectral resolution with 1024 channels, and minimum rms noise after 1 minute integration, for the given correlator bandwidth, for each sense of polarization, at 4874 MHz.
Correlator Velocity Correlator RMS Noise RMS Noise
Bandwidth Range Resolution in 1 min in 1 min
MHz km/s km/s K Jy
32.000 1970.6 1.923 0.045 0.26
16.000 984.8 0.962 0.064 0.37
8.000 492.4 0.481 0.090 0.52
4.000 246.2 0.240 0.128 0.74
2.000 123.1 0.120 0.180 1.05
1.000 61.5 0.060 0.255 1.48
0.500 30.8 0.030 0.361 2.09
0.250 15.4 0.015 0.510 2.96
0.125 7.7 0.008 0.722 4.18