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The Tables

Tables 1-4 give the basic results of these simulations. The simulations are labeled jointly by a sequence number (used in plotting, and unique for each source/flux density combination) and the array configuration. A given simulation often appears several times in these tables, each line corresponding to a different resolution. The configuration names are based on those outlined above, with a few extra twists as follows. A `V' in the configuration name indicates that the deconvolution was done using VTESS rather than CLEAN. Subscripts indicate simulations carried out with different noise realizations Finally, the configurations C-2f, C-4f, C-6f were formed by flagging 2, 4, or 6 antennas from C configuration, to test whether the quality indicators vary as expected (see §[*]). The various columns are other obvious or described in the table captions; one oddity is the rms noise quoted for the VTESS simulations. This refers not to a measured off-source rms noise (since VTESS only gives non-zero values to pixels in the window defining the model support), but to the value of the noise which VTESS tries to match during the deconvolution (i.e., the AIPS parameter NOISE). Similarly the dynamic range was calculated using this for the rms. However, the $5\sigma$ cutoff for $\langle FI_{5\sigma}\rangle$ was based on $\sigma$ for the corresponding CLEAN image, since that seemed to allow more meaningful comparisons.


Table 1a. Image Quality: Cas A (D=385 $^{\prime\prime}$), HA=$\pm4$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 1926 Jy (Seq.= 1)
  C $13.2\times13.1$ 16910 2.94 5750 2205 1082 425 293
  C-2 $13.3\times12.9$ 16820 3.16 5324 1480 718 349 233
CS $13.5\times13.2$ 17250 3.87 4457 3320 2556 361 276
  C " 17270 3.01 5731 1155 594 396 326
  C-2 " 17270 3.26 5299 1520 730 400 280
CS-2 $13.7\times13.4$ 17730 4.03 4400 998 575 378 239
  C-2 " 17780 3.36 5284 1655 1161 433 309
  CS " 17770 4.00 4448 1448 735 441 310
                   
Flux= 9.630 Jy (Seq.= 5)
  C $13.2\times13.1$ 84.76 0.0230 3685 1420 812 363 253
  VC " 84.47 0.0230 3673 872 474 262 408
C-2 $13.3\times12.9$ 83.85 0.0238 3523 2039 872 351 227
  VC-2 " 86.14 0.0238 3530 1150 713 265 378
CS $13.5\times13.2$ 86.15 0.0258 3339 1735 985 429 293
  VCS " 84.02 0.0258 3339 5720 3253 418 362
  C " 86.56 0.0232 3735 2626 1360 394 269
  VC " 86.32 0.0232 3724 938 536 228 453
  C-2 " 86.10 0.0240 3582 1963 1137 403 267
  VC-2 " 86.30 0.0240 3590 930 519 238 416
CS-2 $13.7\times13.4$ 88.69 0.0271 3273 1563 1013 405 279
  VCS-2 " 88.69 0.0271 3275 1427 1042 303 317
  C-2 " 88.67 0.0243 3644 1319 648 457 297
  VC-2 " 88.91 0.0243 3653 1321 678 459 298
  CS " 88.78 0.0263 3375 1884 917 477 342
  VCS " 88.78 0.0263 3375 1896 1152 478 342
                   
Flux= 1.926 Jy (Seq.= 2)
  C $13.2\times13.1$ 14.02 0.0171 820 1119 742 338 247
C-2 $13.3\times12.9$ 14.06 0.0179 786 865 567 303 211
CS $13.5\times13.2$ 14.37 0.0175 821 1033 696 349 233
  C " 14.33 0.0170 844 931 500 426 308
  C-2 " 14.43 0.0178 812 1002 478 342 243
CS-2 $13.7\times13.4$ 14.85 0.0183 810 1000 720 321 243
  C-2 " 14.86 0.0177 839 1706 939 390 268
  CS " 14.80 0.0175 845 1107 647 415 299
                   
  • All these simulations used 50000 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.0170 mJy/beam (0.0184 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.


Table 1b. Image Quality: Cas A (D=385 $^{\prime\prime}$), HA=$0.0-0.1$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 1926 Jy (Seq.= 1)
  C $16.8\times13.4$ 21060 15.53 1356 90.9 46.5 21.9 15.0
C-2 $16.4\times13.6$ 19520 16.04 1217 56.9 31.4 17.0 13.3
CS $17.1\times14.3$ 24700 21.66 1141 45.6 25.6 15.7 13.3
  C " 22680 15.91 1425 230 125 24.0 17.1
  C-2 " 21030 16.66 1263 83.6 41.3 17.6 14.0
CS-2 $16.9\times14.5$ 24930 25.65 972 49.3 26.2 11.5 10.1
  C-2 " 21110 16.83 1254 156 74.2 17.2 14.1
CS $17.2\times15.2$ 26050 22.11 1178 70.7 39.2 16.1 13.7
  CS-2 " 26350 26.37 999 52.0 25.4 12.5 10.5
                   
Flux= 19.07 Jy (Seq.= 6)
  C $16.8\times13.4$ 200 0.2146 932 77.9 43.1 23.6 16.3
  VC " 194.7 0.2146 907 95.4 52.4 26.4 22.7
C-2 $16.4\times13.6$ 200 0.272 733 73.1 38.0 19.6 13.8
  VC-2 " 213.6 0.272 689 71.9 43.5 18.6 18.2
CS $17.1\times14.3$ 248 0.228 1087 68.3 40.8 16.3 13.6
  VCS " 187.5 0.228 937 138 89.8 30.5 22.7
  C " 217.3 0.219 994 82.2 37.2 27.0 19.3
  VC " 210.9 0.219 965 153 71.9 27.1 27.9
  C-2 " 215.1 0.289 743 56.3 33.4 20.6 14.9
  VC-2 " 203.7 0.289 704 134 61.5 18.8 21.5
CS-2 $16.9\times14.5$ 234 0.317 740 69.0 41.4 12.5 11.9
  VCS-2 " 209 0.317 659 85.3 57.9 24.2 19.0
  C-2 " 216.2 0.290 746 73.1 32.1 21.3 15.0
  VC-2 " 203.6 0.290 702 92.2 49.3 19.0 22.1
CS $17.2\times15.2$ 260.9 0.233 1121 69.8 39.8 16.8 14.1
  VCS " 226.6 0.233 974 166 73.5 32.2 23.9
  CS-2 " 247.3 0.326 758 35.8 21.9 13.1 12.5
  VCS-2 " 222 0.326 681 94.7 62.0 24.3 19.7
                   
Flux= 1.926 Jy (Seq.= 2)
  C $16.8\times13.4$ 17.55 0.0630 279 69.9 42.5 20.8 14.5
C-2 $16.4\times13.6$ 16.59 0.0653 254 58.4 34.5 13.1 11.4
CS $17.1\times14.3$ 20.97 0.0759 276 40.7 29.4 14.5 12.4
  C " 19.01 0.0640 297 72.8 45.8 25.2 17.0
  C-2 " 17.95 0.0659 272 75.9 33.4 13.0 11.8
CS-2 $16.9\times14.5$ 20.16 0.0807 250 50.5 40.8 10.7 10.3
  C-2 " 17.95 0.0662 271 141 75.1 13.6 11.8
CS $17.2\times15.2$ 22.12 0.0771 287 102 70.3 15.0 12.9
  CS-2 " 21.43 0.0818 262 41.4 29.0 11.2 10.5
                   
  • All these simulations used 50000 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.143 mJy/beam (0.155 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.


Table 2a. Image Quality: Cyg A ( $130\times\phantom{0}60^{\prime\prime}$), HA=$\pm4$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 352.6 Jy (Seq.=11)
  C $13.2\times13.1$ 81390 3.12 26087 1941 503 355 267
C-2 $13.3\times12.9$ 81210 3.08 26367 2069 552 436 290
CS $13.5\times13.2$ 81900 3.11 26334 967 289 399 296
  C " 81910 3.003 27275 800 214 445 298
  C-2 " 81860 3.009 27206 2394 950 501 327
CS-2 $13.7\times13.4$ 82890 3.21 25822 1718 457 537 391
  C-2 " 82870 2.601 31860 987 283 576 403
  CS " 82910 2.684 30890 1452 319 504 367
                 
Flux= 1.763 Jy (Seq.=12)
  C $13.2\times13.1$ 407.0 0.0234 17418 912 273 367 269
C-2 $13.3\times12.9$ 406.1 0.0240 16928 1433 464 418 291
CS $13.5\times13.2$ 409.5 0.0235 17427 1690 537 408 298
  C " 409.5 0.02291 17876 1197 388 440 299
  C-2 " 409.4 0.02366 17301 1491 437 509 329
CS-2 $13.7\times13.4$ 414.4 0.0246 16832 1227 475 539 389
  C-2 " 414.4 0.02223 18640 1153 334 565 407
  CS " 414.5 0.02208 18775 2739 1410 499 369
                 
Flux= 0.441 Jy (Seq.=14)
  C $13.2\times13.1$ 101.7 0.0179 5695 1081 365 355 279
  VC " 102.4 0.179 572 147 54.1 110 132
C-2 $13.3\times12.9$ 101.5 0.0188 5414 915 986 388 292
  VC-2 " 102.2 0.188 544 161 69.1 111 135
CS $13.5\times13.2$ 102.4 0.0182 5633 1992 483 371 289
  VCS " 103.0 0.182 566 152 53.7 116 138
  C " 102.4 0.01773 5773 1487 2584 429 311
  VC " 103.1 0.1773 582 399 121 103 135
  C-2 " 103.6 0.01859 5505 926 635 457 329
  VC-2 " 103.1 0.1859 554 578 144 115 145
CS-2 $13.7\times13.4$ 103.6 0.0191 5421 1224 460 545 383
  VCS-2 " 104.4 0.191 546 146 59.2 103 143
  C-2 " 102.3 0.01829 5664 5329 1656 546 408
  VC-2 " 104.4 0.1829 571 287 96.1 108 153
  CS " 103.7 0.01797 5768 834 336 525 359
  VCS " 104.4 0.1797 581 154 59.8 105 148
                 
  • All these simulations used 10000 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.0170 mJy/beam (0.0184 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.


Table 2b. Image Quality: Cyg A ( $130\times\phantom{0}60^{\prime\prime}$), HA=$0.0-0.1$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 352.6 Jy (Seq.=11)
  C $16.8\times13.4$ 88960 30.45 2921 17366 3951 208 162
C-2 $16.4\times13.6$ 89110 28.90 3083 513 210 220 177
CS $17.1\times14.3$ 91030 33.7 2702 967 243 254 188
  C " 91030 27.93 3259 1253 440 281 228
  C-2 " 91020 25.95 3508 2108 591 331 241
CS-2 $16.9\times14.5$ 91230 33.32 2739 841 220 223 166
  C-2 " 91300 26.43 3454 1051 426 292 237
CS $17.2\times15.2$ 92640 32.49 2851 2255 577 254 217
  CS-2 " 92580 31.23 2964 586 176 251 196
                   
Flux= 1.763 Jy (Seq.=12)
  C $16.8\times13.4$ 444.5 0.202 2197 505 167 207 167
C-2 $16.4\times13.6$ 444.7 0.189 2347 567 209 223 186
CS $17.1\times14.3$ 455.1 0.210 2164 605 188 278 191
  C " 454.9 0.1914 2377 607 251 326 238
  C-2 " 454.5 0.1770 2568 716 253 320 250
CS-2 $16.9\times14.5$ 456.1 0.219 2082 452 173 198 166
  C-2 " 455.8 0.1807 2523 692 226 319 247
CS $17.2\times15.2$ 463.2 0.2048 2262 1949 627 262 223
  CS-2 " 462.7 0.2110 2193 379 151 267 194
                   
Flux= 0.441 Jy (Seq.=14)
  C $16.8\times13.4$ 110.9 0.135 821 482 183 228 179
  VC " 109.8 0.675 162 358 114 179 119
  C-2 $16.4\times13.6$ 111.1 0.126 883 416 205 242 174
  VC-2 " 110.1 0.630 175 626 180 156 114
CS $17.1\times14.3$ 113.9 0.138 825 500 223 273 180
  VCS " 112.7 0.690 163 304 83.4 207 127
  C " 113.5 0.1330 854 2839 1436 326 255
  VC " 112.9 0.6650 170 307 309 175 142
  C-2 " 113.5 0.1235 919 411 145 310 223
  VC-2 " 112.9 0.6175 182 283 114 173 146
CS-2 $16.9\times14.5$ 113.7 0.138 824 350 272 199 145
  VCS-2 " 112.3 0.690 163 610 103 119 97.6
  C-2 " 113.9 0.1249 912 325 131 304 222
  VC-2 " 113.3 0.6245 181 237 79.5 166 237
CS $17.2\times15.2$ 115.9 0.1374 844 483 212 294 209
  VCS " 115.1 0.6870 167 352 83.4 163 132
  CS-2 " 115.4 0.1381 835 377 203 240 166
  VCS-2 " 114.2 0.6905 165 677 139 148 113
                   
  • All these simulations used 1200 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.143 mJy/beam (0.155 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.


Table 3a. Image Quality: Cyg A ( $260\times120^{\prime\prime}$), HA=$\pm4$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 352.6 Jy (Seq.=21)
  C $13.2\times13.1$ 54690 0.748 73112 922 490 568 344
C-2 $13.3\times12.9$ 54650 0.700 78037 1454 330 551 362
CS $13.5\times13.2$ 55000 0.927 59337 1291 346 550 359
  C " 55030 0.7196 76469 2445 386 599 395
  C-2 " 55030 0.6855 80280 1594 383 622 410
CS-2 $13.7\times13.4$ 55430 1.03 53976 1379 345 651 402
  C-2 " 55440 0.5971 92852 4286 918 723 484
  CS " 55430 0.8056 68800 1603 408 694 431
                 
Flux= 3.526 Jy (Seq.=22)
  C $13.2\times13.1$ 547.0 0.0191 28654 2211 600 509 347
  VC " 553.1 0.287 1931 265 73.1 145 108
C-2 $13.3\times12.9$ 546.6 0.0198 27642 5640 1099 570 363
  VC-2 " 552.3 0.297 1859 278 82.0 152 110
CS $13.5\times13.2$ 550.1 0.0202 27246 1376 419 551 356
  VCS " 556.2 0.303 1836 342 103 144 109
  C " 550.4 0.01888 29151 1126 349 625 398
  VC " 556.5 0.2832 1965 226 76.5 137 109
  C-2 " 550.4 0.01957 28126 1671 567 650 410
  VC-2 " 556.1 0.2935 1894 8264 2453 142 114
CS-2 $13.7\times13.4$ 554.3 0.0210 26377 1289 465 626 401
  VCS-2 " 560.5 0.315 1779 794 276 118 110
  C-2 " 554.5 0.01902 29153 1156 395 745 487
  VC-2 " 560.3 0.2853 1964 296 105 135 118
  CS " 554.3 0.01954 28367 4896 1237 702 428
  VCS " 560.5 0.2931 1912 545 203 128 113
                 
  • All these simulations used 20000 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.0170 mJy/beam (0.0184 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.


Table 3b. Image Quality: Cyg A ( $260\times120^{\prime\prime}$), HA=$0.0-0.1$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 352.6 Jy (Seq.=21)
  C $16.8\times13.4$ 57650 8.63 6679 617 561 117 80.6
C-2 $16.4\times13.6$ 57740 12.71 4542 449 143 97.0 75.7
CS $17.1\times14.3$ 58840 12.44 4729 161 57.8 95.2 75.8
  C " 58960 7.694 7663 445 131 172 104
  C-2 " 59100 10.39 5688 319 108 133 98.0
CS-2 $16.9\times14.5$ 58940 15.04 3919 1359 319 78.1 62.4
  C-2 " 59020 11.05 5342 514 218 143 99.5
CS $17.2\times15.2$ 59980 12.34 4860 242 77.6 95.2 83.7
  CS-2 " 59980 12.78 4693 191 82.0 93.7 75.2
                   
Flux= 3.526 Jy (Seq.=22)
  C $16.8\times13.4$ 575.7 0.126 4555 388 146 118 83.5
  VC " 577.2 0.882 654 230 85.8 75.3 66.8
C-2 $16.4\times13.6$ 576.9 0.153 3761 1271 1791 109 77.8
  VC-2 " 573.4 1.071 535 166 36.7 78.9 60.7
CS $17.1\times14.3$ 587.7 0.171 3434 195 77.8 97.8 75.4
  VCS " 591.1 1.197 494 248 62.1 83.7 62.5
  C " 589.0 0.1226 4804 551 192 172 108
  VC " 592.3 0.8582 690 258 76.1 89.6 80.4
  C-2 " 590.6 0.1358 4349 313 94.7 130 102
  VC-2 " 589.1 0.9506 620 195 43.0 98.5 76.6
CS-2 $16.9\times14.5$ 589.6 0.184 3200 171 84.9 81.0 61.2
  VCS-2 " 587.2 1.288 456 206 56.3 72.4 52.4
  C-2 " 589.9 0.1397 4223 501 141 141 104
  VC-2 " 591.0 0.9779 604 198 60.0 93.5 71.2
CS $17.2\times15.2$ 599.7 0.1704 3520 319 195 97.6 80.7
  VCS " 604.0 1.1928 506 183 39.2 91.3 69.2
  CS-2 " 599.8 0.1660 3613 166 90.9 92.4 73.1
  VCS-2 " 598.4 1.1620 515 288 103 85.3 61.7
                   
  • All these simulations used 5000 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.143 mJy/beam (0.155 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.


Table 4a. Image Quality: Cyg A ( $360\times140^{\prime\prime}$), HA=$\pm4$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 352.6 Jy (Seq.=31)
  C $13.2\times13.1$ 51120 0.452 113071 1022 348 428 256
C-2 $13.3\times12.9$ 51090 0.502 101867 886 283 459 268
CS $13.5\times13.2$ 51360 0.590 87012 1085 311 329 260
  C " 51350 0.5111 100469 1310 580 484 285
  C-2 " 51340 0.4884 105119 1208 305 550 298
CS-2 $13.7\times13.4$ 51730 0.579 89334 1578 407 584 332
  C-2 " 51710 0.4238 119481 874 288 564 367
  CS " 51730 0.5193 99615 1343 529 496 327
                 
Flux= 3.526 Jy (Seq.=32)
  C $13.2\times13.1$ 511.1 0.0180 28343 879 373 419 258
  VC " 514.8 0.180 2860 299 109 114 158
C-2 $13.3\times12.9$ 510.9 0.0188 27337 657 279 617 281
  VC-2 " 514.3 0.188 2736 429 136 111 164
CS $13.5\times13.2$ 513.6 0.0188 27236 1192 428 316 262
  VCS " 517.1 0.188 2751 412 180 111 161
  CS$_2$ " 513.6 0.0188 27379 4749 565 320 258
  CS$_3$ " 513.6 0.0188 27322 2218 741 336 255
  CS$_4$ " 513.6 0.0177 29056 1106 549 320 258
  CS$_5$ " 513.6 0.0189 27232 831 325 329 254
  C " 513.4 0.0179 28680 1119 442 454 290
  VC " 517.4 0.179 2890 276 123 108 163
  C-2 " 513.4 0.0186 27602 949 813 510 291
  VC-2 " 517.0 0.186 2780 383 153 113 168
CS-2 $13.7\times13.4$ 517.3 0.0196 26442 1234 464 441 321
  VCS-2 " 521.4 0.196 2660 426 169 100 171
  C-2 " 517.1 0.0183 28257 1017 587 657 366
  VC-2 " 521.1 0.183 2848 577 268 113 183
  CS " 517.3 0.0185 27962 1011 434 393 315
  VCS " 521.3 0.185 2818 284 161 109 171
  CS-2f " 517.2 0.0198 26146 841 359 603 333
CS-4f $15.0\times13.1$ 526.1 0.0210 25018 1299 532 559 445
  CS-6f $19.5\times12.9$ 555.5 0.0233 23823 369 153 316 195
CS $15.0\times13.1$ 525.9 0.0188 27975 1658 922 678 490
  CS-2f " 525.9 0.0198 26559 2660 1269 810 504
  CS-4f " 526.1 0.0210 25052 1533 627 550 447
  CS-6f " 536.2 0.0233 23013 151 65.6 79.0 58.7
                 
  • All these simulations used 50000 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. CS$_2$ etc. are identical simulations carried out with different realizations of the thermal noise. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.0170 mJy/beam (0.0184 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.


Table 4b. Image Quality: Cyg A ( $360\times140^{\prime\prime}$), HA=$0.0-0.1$ hours
                   
    Resolution Peak $\sigma$       Med.Pk. Peak
  Config. [arcsec] [mJy/bm] [mJy/bm] DR $\langle FI_S\rangle$ $\langle FI_{5\sigma}\rangle$ FI SNR
                   
Flux= 352.6 Jy (Seq.=31)
  C $16.8\times13.4$ 54100 6.03 8974 302 78.3 163 114
C-2 $16.4\times13.6$ 54290 6.123 8867 215 83.4 160 131
CS $17.1\times14.3$ 55080 8.035 6855 268 117 182 127
  C " 54900 5.048 10875 253 81.9 201 150
  C-2 " 54950 5.480 10027 348 83.2 169 127
CS-2 $16.9\times14.5$ 55260 7.048 7840 305 77.2 125 147
  C-2 " 55080 5.101 10798 324 76.1 252 169
CS $17.2\times15.2$ 55680 6.531 8526 364 94.0 229 180
  CS-2 " 55730 6.215 8968 371 90.1 215 151
                   
Flux= 3.526 Jy (Seq.=32)
  C $16.8\times13.4$ 540.8 0.103 5235 787 907 165 128
  VC " 528.4 0.515 1026 177 54.1 99.5 69.9
C-2 $16.4\times13.6$ 532.3 0.106 5118 222 69.5 143 135
  VC-2 " 526.5 0.530 993 201 42.2 71.5 65.8
CS $17.1\times14.3$ 550.4 0.119 4621 518 202 207 151
  VCS " 539.9 0.595 907 491 75.2 125 84.2
  C " 548.7 0.09758 5623 422 127 191 185
  VC " 539.9 0.4879 1107 4354 654 105 83.8
  C-2 " 549.0 0.1023 5367 286 82.7 184 164
  VC-2 " 536.4 0.5115 1049 866 194 85.9 75.2
CS-2 $16.9\times14.5$ 552.8 0.114 4844 218 62.0 146 149
  VCS-2 " 538.6 0.570 945 140 31.1 94.5 68.2
  C-2 " 550.3 0.1010 5450 396 130 201 167
  VC-2 " 538.3 0.5050 1066 720 349 89.3 79.0
CS $17.2\times15.2$ 556.5 0.1131 4921 481 164 221 172
  VCS " 548.7 0.5655 970 284 60.3 150 95.9
  CS-2 " 557.5 0.1096 5087 787 127 165 176
  VCS-2 " 545.6 0.5480 996 399 88.3 108 83.7
                   
  • All these simulations used 12500 CLEAN components (with GAIN=0.1 and FACTOR$=-1$). The ``Seq.'' numbers are used in some plots (e.g., Figure [*]). A configuration beginning with `V' indicates a VTESS map. $\sigma\rightarrow$ RMS noise - expected thermal noise is 0.143 mJy/beam (0.155 mJy/beam for ``-2'' configurations). DR$\rightarrow$ dynamic range; FI$\rightarrow$ fidelity index; SNR$\rightarrow$ signal-to-noise ratio. See text for further explanation.

                 

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Next: Discussion of the Measures Up: Simulations Previous: Measuring the Image Quality
Stephan Witz 2003-04-15