The VIRUS and LRS2 commissioning work requires that we assemble target fields with know astromtric positions. We'd like to grade these targets by the number of stars (per IFU) each will provide, as well as target availability in the April-May time period. Here I demonstrate the methods used to gather our list in:
/home/sco/VIR+LRS_Apr2016/Targets This will presumably beplaced in: /home/sco/sco/projects/VIRUS/VIR+LRS_Apr2016/Targets
A text copy of the Revised NGC (RNGC) was obtained online for use in making initial target lists for our commissioning run in Apr2016. I show an example below of how I gather a list with rngc. Below I assemble a list of open clusters (last column = 1) and globular clusters (last column = 2). The Ra,Dec ranges specified in the RADEC.LIMITS file below are probably a little wide for mid-Spring, but we'll deal with that later.
% rngc Usage: rngc.sh 2 1 arg1 - object type (1=open cl. 2=glob.cl. 5=galaxy) arg2 - Ra,Dec format (1=degrees, 2=sexigecimal) % cat RADEC.LIMITS 8.0 20.0 -6.0 67.0 % rngc.sh 1 2 > List.0 % rngc.sh 2 2 >> List.0 % cat List.0 08:12:24.00 -05:43:00.0 1975.0 NGC2548 1 08:38:36.00 +20:05:00.0 1975.0 NGC2632 1 08:49:42.00 +11:54:00.0 1975.0 NGC2682 1 18:26:18.00 +06:33:00.0 1975.0 NGC6633 1 18:49:30.00 -05:14:00.0 1975.0 NGC6704 1 18:50:18.00 +10:19:00.0 1975.0 NGC6709 1 19:00:12.00 +11:34:00.0 1975.0 NGC6738 1 19:06:30.00 +04:10:00.0 1975.0 NGC6755 1 19:07:24.00 +04:37:00.0 1975.0 NGC6756 1 19:19:54.00 +37:48:00.0 1975.0 NGC6791 1 19:22:06.00 +22:08:00.0 1975.0 NGC6793 1 19:26:06.00 +25:05:00.0 1975.0 NGC6800 1 19:29:30.00 +20:13:00.0 1975.0 NGC6802 1 19:37:24.00 +46:30:00.0 1975.0 NGC6811 1 19:39:54.00 +26:47:00.0 1975.0 NGC6815 1 19:40:30.00 +40:08:00.0 1975.0 NGC6819 1 19:47:48.00 +21:09:00.0 1975.0 NGC6827 1 19:50:00.00 +23:01:00.0 1975.0 NGC6830 1 19:51:12.00 +29:21:00.0 1975.0 NGC6834 1 19:55:30.00 +30:17:00.0 1975.0 NGC6846 1 12:08:54.00 +18:41:00.0 1975.0 NGC4147 2 13:11:42.00 +18:18:00.0 1975.0 NGC5024 2 13:15:06.00 +17:48:00.0 1975.0 NGC5053 2 13:41:06.00 +28:30:00.0 1975.0 NGC5272 2 14:04:18.00 +28:39:00.0 1975.0 NGC5466 2 14:28:18.00 -05:52:00.0 1975.0 NGC5634 2 15:17:18.00 +02:11:00.0 1975.0 NGC5904 2 16:40:48.00 +36:30:00.0 1975.0 NGC6205 2 16:45:54.00 -01:55:00.0 1975.0 NGC6218 2 16:46:18.00 +47:34:00.0 1975.0 NGC6229 2 16:55:48.00 -04:04:00.0 1975.0 NGC6254 2 17:16:24.00 +43:10:00.0 1975.0 NGC6341 2 17:26:24.00 -05:03:00.0 1975.0 NGC6366 2 17:36:18.00 -03:16:00.0 1975.0 NGC6402 2 17:43:36.00 +03:11:00.0 1975.0 NGC6426 2 18:02:36.00 -00:18:00.0 1975.0 NGC6535 2 19:03:54.00 +01:50:00.0 1975.0 NGC6749 2 19:09:54.00 +00:59:00.0 1975.0 NGC6760 2 19:15:36.00 +30:08:00.0 1975.0 NGC6779 2 19:52:36.00 +18:43:00.0 1975.0 NGC6838 2In the table above we now have Ra,Dec,Equinox, object name , and type code (1=open, 2=globular). I can use precess_list to get my coordinates into the J2000.0 equinox. This code typically handle Ra,Dec,Eq,Name. In this case the Name+Type code will be preserved as a single string (the "name") and we'll preserve the type codes in our listing:
% precess_list List.0 2000.0 List.1 % cat List.1 08:13:38.0523 -05:47:34.784 2000.0 NGC2548 1 01:53 08:40:02.2224 +19:59:39.044 2000.0 NGC2632 1 08:51:04.0320 +11:48:20.840 2000.0 NGC2682 1 18:27:31.0529 +06:33:58.700 2000.0 NGC6633 1 18:50:49.8459 -05:12:11.188 2000.0 NGC6704 1 18:51:28.9366 +10:20:50.361 2000.0 NGC6709 1 19:01:22.2533 +11:36:11.352 2000.0 NGC6738 1 10:32 19:07:44.5294 +04:12:24.669 2000.0 NGC6755 1 19:08:38.2732 +04:39:26.549 2000.0 NGC6756 1 19:20:46.5088 +37:50:52.084 2000.0 NGC6791 1 19:23:10.1413 +22:10:56.790 2000.0 NGC6793 1 19:27:08.3180 +25:08:04.916 2000.0 NGC6800 1 19:30:35.4858 +20:16:11.857 2000.0 NGC6802 1 10:37 19:38:08.7886 +46:33:27.353 2000.0 NGC6811 1 10:18 19:40:55.5817 +26:50:32.590 2000.0 NGC6815 1 19:41:21.3583 +40:11:33.622 2000.0 NGC6819 1 19:48:53.3427 +21:12:48.164 2000.0 NGC6827 1 19:51:04.2792 +23:04:52.422 2000.0 NGC6830 1 19:52:12.2433 +29:24:54.683 2000.0 NGC6834 1 19:56:29.7766 +30:21:02.933 2000.0 NGC6846 1 10:45 12:10:10.4004 +18:32:39.329 2000.0 NGC4147 2 13:12:55.4562 +18:10:03.630 2000.0 NGC5024 2 13:16:19.4003 +17:40:05.992 2000.0 NGC5053 2 13:42:15.1021 +28:22:27.404 2000.0 NGC5272 2 14:05:25.4322 +28:31:51.443 2000.0 NGC5466 2 10:20 14:29:36.9630 -05:58:38.936 2000.0 NGC5634 2 15:18:33.9175 +02:05:34.447 2000.0 NGC5904 2 16:41:41.6144 +36:27:11.181 2000.0 NGC6205 2 16:47:11.9458 -01:57:37.863 2000.0 NGC6218 2 16:47:00.2042 +47:31:22.343 2000.0 NGC6229 2 07:27 16:57:07.1645 -04:06:17.155 2000.0 NGC6254 2 17:17:10.1056 +43:08:26.071 2000.0 NGC6341 2 17:27:43.7970 -05:04:11.765 2000.0 NGC6366 2 17:37:36.7772 -03:16:50.299 2000.0 NGC6402 2 17:44:51.0118 +03:10:25.536 2000.0 NGC6426 2 18:03:53.0406 -00:17:52.912 2000.0 NGC6535 2 19:05:09.8351 +01:52:19.241 2000.0 NGC6749 2 19:11:10.3102 +01:01:31.802 2000.0 NGC6760 2 19:16:34.5168 +30:10:43.325 2000.0 NGC6779 2 10:05 19:53:42.8806 +18:46:57.485 2000.0 NGC6838 2Just for yuks I have manually added the htopx2 Start Time value (UT times in BLUE text) for some of these objects computed for the night of April 1,2016. We can see that most of our clusters are observable in either the very start of the night or the very end of the night. Start of the (dark) night is about 9pm, and we can use the table below to see that the middle of the night is very weak in open and globular clusters:
LST=05:56 UT=00:09 7pm LST=06:45 UT=00:58 8pm LST=10:45 UT=04:58 12am LST=16:45 UT=10:58 6am (made these estimates with skycal.sh)
Which targets will have the highest numbers of stars in the IFUs? We can use the star_dens script to compute the number of stars per sq.deg. gathers from USNOB1.0 in each of our fields. Because each IFU is 50" on a side, this denisty corresponds roughly to the number of stars we expect per IFU.
NOTE: For this project, it is best to use ALL targets (see below) % cat SGV.values 0.0 11.5 19.5 % star_dens Usage: star_dens filename file.out arg1 = filename for list of [RAsex,DECsex,Name] arg2 = Name of output file % star_dens List.1 List.2 NOTE: This takes a few minutes to run, but what the hey. % cat star_dens.explain star_dens analysis for: List.1 Ra,Dec,b,Name,Density % cat List.2 12:49:00.0000 +27:24:00.000 89.9999466 2000.0 NGalPole 0 0.70426 08:13:38.0523 -05:47:34.784 15.8052921 2000.0 NGC2548 1 4.06800 08:40:02.2224 +19:59:39.044 33.0886650 2000.0 NGC2632 1 1.37271 08:51:04.0320 +11:48:20.840 32.3738823 2000.0 NGC2682 1 1.71251 18:27:31.0529 +06:33:58.700 7.7687998 2000.0 NGC6633 1 12.03609 18:50:49.8459 -05:12:11.188 -2.7970443 2000.0 NGC6704 1 27.61020 18:51:28.9366 +10:20:50.361 4.1976800 2000.0 NGC6709 1 40.44843 19:01:22.2533 +11:36:11.352 2.6158173 2000.0 NGC6738 1 14.69318 19:07:44.5294 +04:12:24.669 -2.2104452 2000.0 NGC6755 1 14.14569 19:08:38.2732 +04:39:26.549 -2.1986613 2000.0 NGC6756 1 10.90848 19:20:46.5088 +37:50:52.084 10.6887817 2000.0 NGC6791 1 13.64197 19:23:10.1413 +22:10:56.790 2.9598231 2000.0 NGC6793 1 13.23771 19:27:08.3180 +25:08:04.916 3.5736103 2000.0 NGC6800 1 29.81211 19:30:35.4858 +20:16:11.857 0.5225502 2000.0 NGC6802 1 15.88128 19:38:08.7886 +46:33:27.353 11.7839298 2000.0 NGC6811 1 7.62591 19:40:55.5817 +26:50:32.590 1.7104149 2000.0 NGC6815 1 21.74375 19:41:21.3583 +40:11:33.622 8.2451458 2000.0 NGC6819 1 8.26969 19:48:53.3427 +21:12:48.164 -2.7115574 2000.0 NGC6827 1 25.80379 19:51:04.2792 +23:04:52.422 -2.1833515 2000.0 NGC6830 1 18.26780 19:52:12.2433 +29:24:54.683 0.8843585 2000.0 NGC6834 1 15.48418 19:56:29.7766 +30:21:02.933 0.5814683 2000.0 NGC6846 1 19.03971 12:10:10.4004 +18:32:39.329 77.4295120 2000.0 NGC4147 2 0.64776 13:12:55.4562 +18:10:03.630 79.2510986 2000.0 NGC5024 2 2.03002 13:16:19.4003 +17:40:05.992 78.4086227 2000.0 NGC5053 2 1.40534 13:42:15.1021 +28:22:27.404 78.1988525 2000.0 NGC5272 2 4.51841 14:05:25.4322 +28:31:51.443 73.1049423 2000.0 NGC5466 2 1.43956 14:29:36.9630 -05:58:38.936 48.7056046 2000.0 NGC5634 2 1.11408 15:18:33.9175 +02:05:34.447 46.1958885 2000.0 NGC5904 2 6.82377 16:41:41.6144 +36:27:11.181 40.5430145 2000.0 NGC6205 2 5.84496 16:47:11.9458 -01:57:37.863 25.7170563 2000.0 NGC6218 2 6.47522 16:47:00.2042 +47:31:22.343 40.0681725 2000.0 NGC6229 2 1.39818 16:57:07.1645 -04:06:17.155 22.4814911 2000.0 NGC6254 2 6.94552 17:17:10.1056 +43:08:26.071 34.5666122 2000.0 NGC6341 2 4.75396 17:27:43.7970 -05:04:11.765 15.4497557 2000.0 NGC6366 2 6.35506 17:37:36.7772 -03:16:50.299 14.2000246 2000.0 NGC6402 2 7.60601 17:44:51.0118 +03:10:25.536 15.6865158 2000.0 NGC6426 2 8.40179 18:03:53.0406 -00:17:52.912 9.8603449 2000.0 NGC6535 2 12.19366 19:05:09.8351 +01:52:19.241 -2.7225225 2000.0 NGC6749 2 10.07530 19:11:10.3102 +01:01:31.802 -4.4453001 2000.0 NGC6760 2 31.55963 19:16:34.5168 +30:10:43.325 8.0026865 2000.0 NGC6779 2 13.97699 19:53:42.8806 +18:46:57.485 -4.9351754 2000.0 NGC6838 2 24.35389Notice that I am now referring to Name as "Equinox NGC# Type", but this is okay. I'd like to carry this information around with each target. In my new file (List.2) I have added the galactic latitude (b) in col03 and the star density (# of star per sq.arcmin) in col07.
Given a local sidereal time (LST) we'd like to know which of our targets from the above list are visible. I use the "my_targets" routine for this.
% cat List.2 % my_targets List.2 16:00:00 19:20:46.5088 +37:50:52.084 10.6887817 2000.0 NGC6791 1 1.60349 66.628 13:12:55.4562 +18:10:03.630 79.2510986 2000.0 NGC5024 2 0.73848 257.585 13:16:19.4003 +17:40:05.992 78.4086227 2000.0 NGC5053 2 0.62866 256.597 13:42:15.1021 +28:22:27.404 78.1988525 2000.0 NGC5272 2 2.48282 276.678 16:47:11.9458 -01:57:37.863 25.7170563 2000.0 NGC6218 2 2.85922 156.400 17:44:51.0118 +03:10:25.536 15.6865158 2000.0 NGC6426 2 0.53794 137.290 19:16:34.5168 +30:10:43.325 8.0026865 2000.0 NGC6779 2 0.10425 80.098 % cat my_targets.explain # Targets from input HET list visible at LST = 16:00:00 # Name RA DEC AZhet # line numbers of selected targets in Lines.SelectedAs with the previous example, the "Name" is everything after the Ra,Dec. I simply tack on the HET AZ a selected obkect will be observed at (if it is selected to be printed out). This script may seem a little klunky with regard to global planning of a night. However, we often want to know the answer to "What is visible now?", and this fits the bill. With a little wrapper script, I can use "my_targets" to get a good idea of what an entire night might present. I make a file of LST times (list.LST) that spans the start and end of my planned night. I run the script "lists_by_lst":
% cat list.LST 08:00:00 09:00:00 10:00:00 11:00:00 12:00:00 13:00:00 14:00:00 15:00:00 16:00:00 17:00:00 % lists_by_lst List.2 list.LST 08:00:00 2 het-list.1 09:00:00 1 het-list.2 10:00:00 2 het-list.3 11:00:00 7 het-list.4 12:00:00 2 het-list.5 13:00:00 1 het-list.6 14:00:00 6 het-list.7 15:00:00 4 het-list.8 16:00:00 8 het-list.9 17:00:00 25 het-list.10 Suppose I want to see the object available around LST=11:00:00: % cat het-list.4 LST = 11:00:00 08:40:02.2224 +19:59:39.044 33.0886650 2000.0 NGC2632 1 0.56977 261.145 08:51:04.0320 +11:48:20.840 32.3738823 2000.0 NGC2682 1 0.72893 244.387 13:12:55.4562 +18:10:03.630 79.2510986 2000.0 NGC5024 2 0.73848 102.415 13:16:19.4003 +17:40:05.992 78.4086227 2000.0 NGC5053 2 0.62866 103.403 13:42:15.1021 +28:22:27.404 78.1988525 2000.0 NGC5272 2 2.48282 83.322 14:05:25.4322 +28:31:51.443 73.1049423 2000.0 NGC5466 2 0.78941 83.041Hence, I might consider observing NGC5272, at AZ=83.3, because it has a high star density (2.48 per sq.arcmin) compared to the other available clusters.
From the section above I can take a table of clusters that are appropriate for a give time of night and make finding charts for some of the fields. In the sample below I use the LST=17:00:00 set (in het-list.10) and demo finding charts for a high density cluster (NGC6815). I use a tool named "rot" (RA Observing Tool) that allows the user to adjust the IHMP center (to optimize the number of stars per IFU) and select a guide star. In the table below, the estimate star density (from V<19.5 USNOB1.0 stars) is in column 7.
% cat het-list.10 LST = 17:00:00 18:27:31.0529 +06:33:58.700 7.7687998 2000.0 NGC6633 1 0.63742 127.968 18:51:28.9366 +10:20:50.361 4.1976800 2000.0 NGC6709 1 2.22578 118.877 19:01:22.2533 +11:36:11.352 2.6158173 2000.0 NGC6738 1 0.38436 116.060 19:07:44.5294 +04:12:24.669 -2.2104452 2000.0 NGC6755 1 1.02416 134.292 19:08:38.2732 +04:39:26.549 -2.1986613 2000.0 NGC6756 1 1.11011 133.034 19:20:46.5088 +37:50:52.084 10.6887817 2000.0 NGC6791 1 1.60349 66.628 19:23:10.1413 +22:10:56.790 2.9598231 2000.0 NGC6793 1 0.37401 94.686 19:30:35.4858 +20:16:11.857 0.5225502 2000.0 NGC6802 1 3.24039 98.324 19:38:08.7886 +46:33:27.353 11.7839298 2000.0 NGC6811 1 1.30427 51.337 19:40:55.5817 +26:50:32.590 1.7104149 2000.0 NGC6815 1 7.35296 86.086 19:41:21.3583 +40:11:33.622 8.2451458 2000.0 NGC6819 1 0.16552 62.539 19:48:53.3427 +21:12:48.164 -2.7115574 2000.0 NGC6827 1 4.15792 96.520 19:51:04.2792 +23:04:52.422 -2.1833515 2000.0 NGC6830 1 3.40035 93.001 19:52:12.2433 +29:24:54.683 0.8843585 2000.0 NGC6834 1 0.69312 81.459 19:56:29.7766 +30:21:02.933 0.5814683 2000.0 NGC6846 1 0.42176 79.792 13:42:15.1021 +28:22:27.404 78.1988525 2000.0 NGC5272 2 2.48282 276.678 14:05:25.4322 +28:31:51.443 73.1049423 2000.0 NGC5466 2 0.78941 276.959 15:18:33.9175 +02:05:34.447 46.1958885 2000.0 NGC5904 2 3.55552 219.377 16:57:07.1645 -04:06:17.155 22.4814911 2000.0 NGC6254 2 4.07835 172.798 17:27:43.7970 -05:04:11.765 15.4497557 2000.0 NGC6366 2 4.03219 180.000 17:37:36.7772 -03:16:50.299 14.2000246 2000.0 NGC6402 2 4.21044 164.368 18:03:53.0406 -00:17:52.912 9.8603449 2000.0 NGC6535 2 0.11300 149.044 19:16:34.5168 +30:10:43.325 8.0026865 2000.0 NGC6779 2 0.10425 80.098 19:53:42.8806 +18:46:57.485 -4.9351754 2000.0 NGC6838 2 1.53505 101.207
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A finding chart for NGC6815 generated with:
rot NGC6815 19:40:55.5817 +26:50:32.590 86.086This cluster was selected from the LST=17:00:00 group (previous section) as being a HIGH stellar density field. In addition to revising the IHMP position for this field (small red circle) the user may select a guide star. |
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A finding chart for NGC6738 generated with:
rot NGC6738 19:01:22.2533 +11:36:11.352 116.060This cluster was selected from the LST=17:00:00 group (previous section) as being a LOW stellar density field. |
It would appear that the density of usable IFU stars does not vary greatly. This is probably due to the large field gathered from the USNOB1.0 catalog (Radius = 24' in diameter) and the fairly bright magnitude cut of V.le.19.5 . Actually, digging a little deeper reveals that the problem is poor star/gal separation in USNOB1.0 at low galactic latitudes. I just use usno_look to view few fields:
Cluster fields rot NGC6815 19:40:55.5817 +26:50:32.590 86.086 rot NGC6738 19:01:22.2533 +11:36:11.352 116.060 low density field rot NGP1 12:30:22.2533 +31:36:11.352 -999 rot NGP2 12:30:22.2533 +21:36:11.352 -999 I can visually see a difference, does star_dens? % star_dens l.1 OUT % cat OUT 19:40:55.5817 +26:50:32.590 1.7104149 s1 7.35296 19:01:22.2533 +11:36:11.352 2.6158173 s2 0.38436 12:30:22.2533 +31:36:11.352 84.1621399 n1 0.28489 12:30:22.2533 +21:36:11.352 82.8211365 n2 0.34855 ANSWER: No! Here we use the ds9 region files (bote STAR and GALS) from usno_look: CLUSTERS at b < 5 degrees % usno_look 19:40:55.5817 +26:50:32.590 12.0 19.5 wc -l *reg 6285 gals.reg 2851 stars.reg 9136 total % usno_look 19:01:22.2533 +11:36:11.352 12.0 19.5 wc -l *reg 6558 gals.reg 144 stars.reg 6702 total NGP fields (b > 80 degrees) NGP1 % usno_look 12:30:22.2533 +31:36:11.352 12.0 19.5 wc -l *reg 147 gals.reg 132 stars.reg 279 total NGP2 % usno_look 12:30:22.2533 +21:36:11.352 12.0 19.5 wc -l *reg 290 gals.reg 164 stars.reg 454 totalHence, I'll tune up the star_dens code to take this into account. It appear that all I need to do is change the stellarity range for selecting stars. In multi_usno_runs I now use:
# For now hard code the sglo,sghi,Vlim values sglo="5.5" sghi="11.5" Vlim="19.5" if [ -s "SGV.values" ] then read sglo sghi Vlim < SGV.values fiIn other words, I create a local file (SGV.values) that sets the stellary values such that I count ALL sources (stellarity between 0 and 11) and use this to compute the density of targets. After these changes I get the following results:
% ls list.1 SGV.values % cat list.1 19:40:55.5817 +26:50:32.590 NGC6815 19:01:22.2533 +11:36:11.352 NGC6738 12:30:22.2533 +31:36:11.352 NGalPole1 12:30:22.2533 +21:36:11.352 NGalPole2 % cat SGV.values 0.0 11.5 19.5 % star_dens list.1 Out.Star_Densities % cat Out.Star_Densities 19:40:55.5817 +26:50:32.590 1.7104149 NGC6815 21.74375 19:01:22.2533 +11:36:11.352 2.6158173 NGC6738 14.69318 12:30:22.2533 +31:36:11.352 84.1621399 NGalPole1 0.66765 12:30:22.2533 +21:36:11.352 82.8211365 NGalPole2 0.97960Now we see a very pronounced distinction in the densities levels between the low (cluster) and the high (NGP) latitude fields! Hence, I'll re-run some of the examples above to get more useful star density estimates in selecting target fields.
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A finding chart for NGC2632 generated with:
rot NGC2632 08:40:02.22 +19:59:39.0 1.37This cluster field was processed uing the SGV.values file to reset the stellarity ranges for star-galaxy separation in USNOB1.0. This produces more reliable stellar density estimates. The star denisty for this field was dens=1.37, compared to the values of dens=21.7,14.7 for the fields show above. Clearly our star density values now help in identifying fields with high star density. In addition to revising the IHMP position for this field (small red circle) the user may select a guide star. |