TABLE 1 ALMA Configurations Compared with Other Arrays

 

CARMA

PdB

SMA

Nobeyama

ALMA

Latitude (degrees)

39

44

19

36

-23

Altitude (ft)

7200

8300

13500

4400

17000

Fr equency Range (in GHz)

35-250

85-250

186-696

85-250

30-900

Maximum Baseline (km)

3

1

0.5

0.35

12

Best Resolution (mas) at Frequency (GHz)

80 at 250

240 at 250

200 at 696

690 at 250

6 at 850

Usable Time Fraction (250 GHz)

0.25

0.25

0.5

0.1

0.9

Usable Time Fraction (350 GHz)

-

-

0.3

-

0.8

External User Access Fraction

0.3

0.05

0.1

0

0.35

Antenna Number

23

6

8

6

60

50

40

30

Antenna Diameter (in meters)

3.5 - 10

15

6

10

12

50

40

30

Image Fidelity ~N3

0.056

0.001

0.002

0.001

1.00

0.58

0.30

0.13

Imaging Speed ~N 2D4

0.006

0.024

0.001

0.005

1.00

0.69

0.44

0.25

Single Field Sensitivity ~ND2

0.12

0.16

0.03

0.07

1.00

0.83

0.67

0.50

Mosaiced Image Sensitivity ~ND

0.20

0.13

0.07

0.08

1.00

0.83

0.67

0.05



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