Expected Capabilities
All EVLA antennas are outfitted with either EVLA or "interim" L, EVLA C, VLA X, EVLA K, EVLA Ka, and EVLA Q-band receivers. (Interim receivers are EVLA receivers with narrowband VLA polarizers. All interim receivers will be converted to full EVLA capabilities by the end of 2012. The polarization purity and sensitivity of the interim receivers typically is good only over the traditional VLA tuning range.) As of July 2012, 25 of the EVLA antennas will be outfitted with S-band receivers, 23 EVLA antennas will have Ku-band receivers, and 22 will have new EVLA-style X-band receivers. Figure 1 shows the expected installation rate of final EVLA receiver systems for the rest of the EVLA construction project. The 8-GHz maximum bandwidth availability depends on the implementation of the fast 3-bit samplers, expected to be commissioned by the end of 2012. Prior to this, the maximum available bandwidth will be 2 GHz per polarization.
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Figure 1: EVLA Receiver Deployment Plan. To the left is a plot of the availability of final EVLA receivers during the calendar year 2012 until the end of the EVLA Construction Project on December 31, 2012. Interim receivers with reduced frequency coverage or polarization purity are available at some bands in addition to those plotted (see Table 4). |
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Figure 1 does not tell the entire story of frequency availability for observing with the EVLA, however, since there are interim or VLA receivers at L and X-bands that can be used in the absence of the final EVLA receivers. Table 4 gives a prediction of the new frequency capabilities that are available in September 2011 and January 2012, along with the expected "total" numbers of receivers for a given band, including VLA-style and/or interim receivers. New receiver bands will be offered for general use when the performance of at least five antennas has been verified by EVLA commissioning staff.
| Band | Range | Receiver availability, Jan 2012 | Receiver availability, Jul 2012 | ||
|---|---|---|---|---|---|
| GHz | Final EVLA | EVLA+VLA/interim | Final EVLA | EVLA+VLA/interim | |
| 400 cm (4-band) | 0.062-0.078 | - | - | - | - |
| 20 cm (L) | 1.0-2.0 | 19 | 27 | 24 | 27 |
| 13 cm (S) | 2.0-4.0 | 21 | 21 | 25 | 25 |
| 6 cm (C) | 4.0-8.0 | 27 | 27 | 27 | 27 |
| 3 cm (X) | 8.0-12.0 | 16 | 27 | 22 | 27 |
| 2 cm (Ku) | 12.0-18.0 | 18 | 18 | 23 | 23 |
| 1.3 cm (K) | 18.0-26.5 | 27 | 27 | 27 | 27 |
| 1 cm (Ka) | 26.5-40.0 | 27 | 27 | 27 | 27 |
| 0.7 cm (Q) | 40.0-50.0 | 27 | 27 | 27 | 27 |
- Note: The "EVLA+VLA/interim" columns give the total numbers of receivers expected to be available for a given band, including all VLA-style and/or interim receivers (see Figure 1).
