4 Comparison of the ALMA and Herschel - ESO
4 Comparison of the ALMA and Herschel - ESO
4 Comparison of the ALMA and Herschel - ESO
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
Table 1: <strong>ALMA</strong> Antenna Arrays <strong>and</strong> Configurations<br />
Array Bilateral Compact (ACA)<br />
Number <strong>of</strong> Antennas 50, up to 64 16<br />
Total Collecting Area 5654-7237 m 2 915 m 2<br />
Array Configurations<br />
(dimension <strong>of</strong> region filled)<br />
Compact filled<br />
Largest extent<br />
Total Number <strong>of</strong> Antenna<br />
stations<br />
150 m<br />
18.5 km<br />
175 22<br />
35 m<br />
Antenna Diameter 12 m a) 4 x 12 m b) ;12 x 7 m a)<br />
Surface accuracy 25 µm 12 m: 25 μm; 7 m: 20 μm<br />
Field <strong>of</strong> View<br />
3mm 50” 50”; 85”<br />
0.5 mm 8.3” 8.3”; 14”<br />
a)<br />
Transportable by especially constructed vehicles<br />
b)<br />
Fixed in position<br />
Table 2: <strong>ALMA</strong> Front Ends a<br />
B<strong>and</strong> 1 (1cm) 31.3-45 GHz HEMT b<br />
B<strong>and</strong> 2 (4mm) 67-90 GHz HEMT<br />
B<strong>and</strong> 3 (3mm) 84-116 GHz SIS c,d<br />
B<strong>and</strong> 4 (2mm) 125-163 GHz SIS e<br />
B<strong>and</strong> 5 (1.8mm) 163-211 GHz SIS f<br />
B<strong>and</strong> 6 (1.3mm) 211-275 GHz SIS d<br />
B<strong>and</strong> 7 (0.9mm) 275-373 GHz SIS d<br />
B<strong>and</strong> 8 (0.6mm) 385-500 GHz SIS e<br />
B<strong>and</strong> 9 (0.5mm) 602-720 GHz SIS d<br />
B<strong>and</strong> 10 (0.3mm) 787-950 GHz SIS g<br />
a<br />
All with dual polarisation; each polarisation feeds four IF sections, each with a b<strong>and</strong>width <strong>of</strong> 2 GHz, giving a total<br />
b<strong>and</strong>width <strong>of</strong> 8 GHz in each polarisation. Also uncooled 183 GHz water vapour monitors provide data for phase<br />
corrections<br />
b<br />
High Electron Mobility Transistor receiver<br />
c<br />
Superconductor-Insulator-Superconductor mixer receivers.<br />
d<br />
In <strong>the</strong> bilateral baseline plan<br />
e<br />
Contribution from Japan<br />
f<br />
Funded by EC for 6 antennas<br />
g<br />
Contribution from Japan; depends on R&D programme<br />
7
Change language