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TPTCSPNT_071129

Goals

• Ka/CCB half-power tracks at moderate to high winds (>5m/s) to extend the 0-5m/s X-band plots from September
• offset pointing on 10-degree scales (typical of the new Gold standard catalog)
• elevation scans along a tangent of the Moon at high rates (50 to 100'/min) to get QD and receiver data to search for the level of feed arm motion during scans typical of traditional holography
• if the weather craps out: elevation servo tests at constant acceleration (repeat azimuth if there is extra time but only if the temperature is significantly less than 5.1C)
  • Anticipated commands:
    • switch to Az/El coordinates in the Antenna Cleo screen (control window, top pulldown) followed by "update" "move-to"
    • on titania:
      • bash
      • source /home/gbt/gbt.bash
      • cd /home/groups/ptcs/obs/procs
      • glish -l setTrajectory.g

• some results

Observing log

Starting at 00:10 EST, 05:10 UT, weather: 0.3C, 928mBar, 2-5 m/s, mostly clear with waning gibbous moon
Start with SB = multiHalf with 0542+4951 (3c147) and 0359+5057 (bright at high freq)
scan#
 1-5  0542+4951 = 43 counts in elevation peak scan
 6-10 0359+5057 = 537 counts
         az difference was large -29 to +32  (61 deg)
az offset calibration:
 11     "    on-source = 2708 counts
 12          0.4 beam    2500
 13          0.5         2430
 14          0.6         2355 with spread of 100 counts
 15          10 beams    2148 with spread of 8 counts
 16-20 0542+4951  peak/focus
 21              nod
 22-26 0359+5057  peak/focus
 27    0359+5057  half-power track in azimuth, strange downward spikes in the Ref channel at 6:01 and 6:02 UT but not in Sig 
       az difference is now slightly less, +9 to +314 (55 deg)      2007_11_29_05:55:50.fits
       wind1: 3.15(0.92) wind2: 1.96(0.71) wind3: 2.23(0.18)  avg: 2.46 m/s

 28-32 peak/focus on 0542+4951
 33    Nod
 34-38 peak/focus on 0359+5057
 39      half-power track in elevation    2007_11_29_06:30:44.fits
       wind1: 1.40(0.44) wind2: 0.76(0.41) wind3: 1.52(0.26)  avg: 1.23 m/s

 40-44 peak/focus on 0542+4951, wind has dropped to 0.6m/s
 45    Nod
 46-50 peak/focus on 0359+5057,  az difference is now less: -20 to -50 (30 deg), 77 to 63 (14 deg)
07:16 UT:  sky still mostly clear
 51    half-power track in azimuth        2007_11_29_07:04:24.fits 
       wind1: 1.29(0.45) wind2: 1.42(0.45) wind3: 1.30(0.35)   avg: 1.34 m/s
      
 52-56 peak/focus on 0542+4951
 57    Nod
 58-62 peak/focus on 0359+5057
 63    half-power track in elevation (wind = 0.9 m/s)       2007_11_29_07:37:24.fits 
       wind1: 1.06(0.18) wind2: 0.81(0.26) wind3: 1.24(0.19)  avg: 1.04 m/s

08:00 UT  Re-execute multiHalf, this time with numTracks = 1, and using 'el' offset for calibration scans
 64-68  peak/focus on 0542+4951 (az,el = -47,+70)
 69-73  peak/focus on 0359+4951 (        -53,+52)  oscillation seen on Gaussian on first elevation peak scan
 74-78  el offset calibration
 79-83  peak/focus on 0542+4951
 84     nod
 85-89  peak/focus on 0359+4951
 90     half-power track in azimuth                           2007_11_29_08:27:09.fits 
        wind1: 1.12(0.38) wind2: 1.29(0.27) wind3: 1.51(0.34)  avg: 1.31 m/s

 91-95  peak/focus on 0542+4951 (az,el = -54,+62)
 96     nod
 97-101 peak/focus on 0359+4951
102     half-power track in elevation                         2007_11_29_09:00:14.fits
        wind1: 2.08(0.45) wind2: 1.06(0.41) wind3: 1.49(0.29)  avg: 1.54 m/s

09:22 UT completed,  run moonLimb, telescope unwrapping.
First run is using beam 1.  Stop after 3rd of 4 scans (the 3 minute scan)    
       scan 108 = 2007_11_29_09:35:19.fits
Edit moonLimb to use beam 2.  Stop after 3rd of 4 scans (the 3 minute scan)
Create moonLimbFast to use beam 1 but run at twice the rate.  Run up through a 3 minute scan
Create moonLimbFast to use beam 1 but run at four times the rate.
Last scan = 125 = 2007_11_29_10:09:25.fits

10:15 UT switch to elevation constant acceleration scans (with friction compensation), T=-2.3, -2.6, -2.9 C
first attempt caused a Fault due to illegal trajectory.  Kevin cleared it.  Try a lower rate 
                setTrajectory(200, 49, 0.0, +0.25, 0.0, -0.01, 2*0.3/0.01)
            This worked, so try the normal rate again:
10:22 completed setTrajectory(200, 49, 0.0, +0.3, 0.0, -0.01, 2*0.3/0.01)
                setTrajectory(200, 49, 0.0, +0.3, 0.0, -0.02, 2*0.3/0.02)
10:25           setTrajectory(200, 49, 0.0, +0.3, 0.0, -0.03, 2*0.3/0.03)
10:26           setTrajectory(200, 49, 0.0, +0.3, 0.0, -0.04, 2*0.3/0.04) 
10:27           setTrajectory(200, 49, 0.0, +0.3, 0.0, -0.05, 2*0.3/0.05)
10:29           setTrajectory(200, 49, 0.0, -0.3, 0.0, 0.05, 2*0.3/0.05) 
10:30           setTrajectory(200, 49, 0.0, -0.3, 0.0, 0.04, 2*0.3/0.04)
10:31           setTrajectory(200, 49, 0.0, -0.3, 0.0, 0.03, 2*0.3/0.03)
                setTrajectory(200, 49, 0.0, -0.3, 0.0, 0.02, 2*0.3/0.02)
10:34           setTrajectory(200, 49, 0.0, -0.3, 0.0, 0.01, 2*0.3/0.01)
Switch to azimuth: (skies mostly cloudy, can barely see the Moon)
10:38           setTrajectory(200, 51, +0.55, 0.0, -0.01, 0.0, 2*0.55/0.01)
10:40           setTrajectory(200, 51, +0.55, 0.0, -0.03, 0.0, 2*0.55/0.03)
10:42           setTrajectory(200, 51, +0.55, 0.0, -0.05, 0.0, 2*0.55/0.05)
10:44           setTrajectory(200, 51, -0.55, 0.0, 0.05, 0.0, 2*0.55/0.05)
10:45           setTrajectory(200, 51, -0.55, 0.0, 0.03, 0.0, 2*0.55/0.03) 
10:48           setTrajectory(200, 51, -0.55, 0.0, 0.01, 0.0, 2*0.55/0.01)
10:51           setTrajectory(200, 51, -0.55, 0.0, 0.02, 0.0, 2*0.55/0.02)
10:52           setTrajectory(200, 51, -0.55, 0.0, 0.04, 0.0, 2*0.55/0.04)
10:55           setTrajectory(200, 51, 0.55, 0.0, -0.04, 0.0, 2*0.55/0.04)
10:58           setTrajectory(200, 51, 0.55, 0.0, -0.02, 0.0, 2*0.55/0.02)
Done

Some Results

• Az/El Coverage :
  

Summary results of the peak scans are given in this table:

The dAZ and dEL are the average LPCs for each 4-scan peak sequence.

    MeanMJD   SourceName   Scan  AZIM(deg)  ELEV(deg)     P(LCP)  sigP(LCP)     P(RCP)  sigP(RCP)   dAZ(")   dEL(")
 54433.22754    0542+4951      1      39.56      73.99    43.6069     0.1352    43.6069     0.1352     2.10     4.84
 54433.23242    0359+5057      6     -29.23      75.09   534.6257     0.6249   534.6257     0.6249    12.95    10.93
 54433.23828    0542+4951     16      32.59      75.87    62.5777     0.1711    62.5777     0.1711     4.44     8.10
 54433.24512    0359+5057     22     -36.76      73.18   554.1007     0.7594   554.1007     0.7594    15.16    11.31
 54433.26367    0542+4951     28       9.60      78.43    61.3739     0.1550    61.3739     0.1550    10.18     9.64
 54433.26953    0359+5057     34     -46.14      68.61   571.8487     0.6926   571.8487     0.6926    10.88     9.24
 54433.28809    0542+4951     40     -17.47      77.94    59.1163     0.1492    59.1163     0.1492     7.62    10.52
 54433.29297    0359+5057     46     -50.78      63.66   578.9478     0.6284   578.9478     0.6284     7.40     6.74
 54433.31055    0542+4951     52     -36.52      74.91    59.2475     0.1488    59.2475     0.1488     6.67     7.15
 54433.31641    0359+5057     58     -52.88      58.55   582.5123     0.6879   582.5123     0.6879     6.47     7.58
 54433.33594    0542+4951     64     -47.54      70.17    59.4669     0.1676    59.4669     0.1676     6.96     5.02
 54433.33984    0359+5057     69     -53.46      53.19   561.7752     1.5050   561.7752     1.5050     7.79     7.74
 54433.34473    0542+4951     79     -50.07      68.12    58.4371     0.1507    58.4371     0.1507     7.10     4.68
 54433.35059    0359+5057     85     -53.36      50.74   568.3866     0.7659   568.3866     0.7659     8.40     9.74
 54433.36719    0542+4951     91     -53.71      63.01    56.2056     0.1769    56.2056     0.1769     8.13     4.78
 54433.37305    0359+5057     97     -52.55      45.56   539.3702     0.9747   539.3702     0.9747     8.10    10.40
 54433.39746    0854+2006    103     171.51      71.55   142.9176     0.3463   142.9176     0.3463    -0.23     3.34
 54433.40234    0854+2006    110     178.13      71.70   143.8979     0.3009   143.8979     0.3009     1.24     3.53

This can be seen in the following table, in which we list the LPC differences between each successive pair of calibrators. Each line gives differences for the pair (0542+4951, 0359+5057).

     MeanMJD  dT(min)scn1scn2 dAz(deg) dEl(deg)  dArc(deg) dXEl_LPC(")  dEl_LPC(")
 54433.22998     7.03   1   6   -68.79     1.09      17.34       10.85        6.09
 54433.24170     9.84  16  22   -69.35    -2.69      17.61       10.72        3.21
 54433.26660     8.44  28  34   -55.74    -9.81      17.56        0.70       -0.41
 54433.29053     7.03  40  46   -33.31   -14.28      17.47       -0.22       -3.78
 54433.31348     8.44  52  58   -16.35   -16.36      17.44       -0.20        0.43
 54433.33789     5.62  64  69    -5.92   -16.98      17.19        0.83        2.72
 54433.34766     8.44  79  85    -3.28   -17.38      17.46        1.31        5.06
 54433.37012     8.44  91  97     1.16   -17.45      17.46       -0.03        5.62

Lunar ephemeris

Attachment:	Action:	Size:	Date:	Who:	Comment:
gbtcover.gif	action	7701	29 Nov 2007 - 21:09	FrankGhigo	Az/El Coverage