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P68-803: ESA SP2 Program

PIs: K. Muinonen & M. Granvik

Imaging polarimetry requiring differential tracking.

This proposal includes both service observations on fixed dates (see schedule below) and ToO observations triggered on any date.

Instrument setup required for ALFOSC linear polarimetry

  • Filter: R (#76)
  • Aperture wheel: Calcite
  • FAPOL: lambda/2

ToO triggers :

For a ToO trigger the domeflats are not requested, neither are the standards. Otherwise follow the instructions below for the target.

Targets in P69 that are scheduled also for P70 (date is the start of the night) :

Night        Target      UT Window     Duration Mag (V)  Alpha (deg) Sky Rate ("/h)  Other comments

17 Aug 2024  87684      03:30-05:45    0:48     18.1     54.0-54.1   56              Missed due to bad weather. Target postponed due to 2024 ON. 
12 Sep 2024  87684      02:30-06:00    0:34     17.6     45.1        77-78           87684 = 2000 SY2, 1 x 8 angles + 4 angles
17 Sep 2024  Florence   20:00-20:45    0:17     14.7     70.6        183-184         Florence = 3122, 2 x 16 angles
17 Sep 2024  87684      02:15-06:00    0:32     17.4     42.9-43.0   87              1 x 8 angles + 4 angles
23 Sep 2024  87684      02:00-06:15    0:30     17.2     40.0-40.1   198-199         Please avoid exposing at 02:50-03:10 UT due to star overlap!
30 Sep 2024  4953       01:00-03:30    0:48     18.0     18.4        66-67           4953 = 1990 MU. Note that the minimum observation elevation is 25 deg!


 P70: 


Night        Target      UT Window     Duration Mag (V)  Alpha (deg) Sky Rate ("/h)  Other comments

01 Oct 2024  363027     21:15-06:15    0:18     16.3     35.6-36.1   179-212         363027 = 1998 ST27. Avoid the following time windows: 1:30-2:30, 3:30-5:00!
01 Oct 2024  87684      01:30-06:15    0:32     17.0     36.0-36.1   121             -
07 Oct 2024  Florence   19:45-22:00    0:14     14.7     75.5        196-197         1 x 16 angles + 8 angles
07 Oct 2024  363027     20:15-05:15    0:10     14.1     20.6-21.9   880-1038        FAST! 1 x 16 angles + 8 angles
07 Oct 2024  87684      01:15-06:15    0:25     16.8     33.2-33.3   136             The target will transit a galaxy at 2:00-2:15 UT!
13 Oct 2024  363027     19:30-21:30    0:17     14.9     83.7-85.0   2292-2385       2 x 16 angles. Even faster than it was a week ago! Observe as the first target of the night!
13 Oct 2024  87684      01:00-05:30    0:33     16.7     30.9-31.0   221             1 x 16 angles + 4 angles. There will be stars overlapping at 3:45-4:15 UT!
20 Oct 2024  Oljato     02:15-06:30    0:49     17.4     45.2-45.3   145             Oljato = 2201. Missed due to clouds.       
27 Oct 2024  Florence   19:15-22:30    0:12     14.8     73.3        174             Borderline star overlapping around 20:15 UT. 1 x 16 angles + 4 angles. Missed due to high humidity.       
27 Oct 2024  Oljato     02:15-06:30    0:37     17.2     48.2-48.3   169-170         Missed due to high humidity.
31 Oct 2024  Florence   19:15-22:30    0:10     14.8     72.2        168-169         Observe before 22:15 to prevent star overlapping!
31 Oct 2024  Oljato     02:30-06:30    0:39     16.9     51.3-51.4   195-196         Observable between 3:15-4:50, 4:55-5:40, and 5:55-6:30!
05 Nov 2024  4953       20:45-00:30    0:49     17.8     27.9-28.0   63              Observable when elevation is greater than 20 degrees!
10 Nov 2024  163899     19:15-21:30    0:20     15.7     84.3-84.4   198-209         163899 = 2000 AD229 = 2003 SD220. 1 x 16 angles + 8 angles. Air mass limit at 1.94!
10 Nov 2024  Oljato     03:00-06:30    0:29     16.6     58.6-58.7   256-257         Avoid observing the target at 3:50-4:50 to prevent star overlap! Missed due to high wind.
19 Nov 2024  4953       20:00-22:45    0:49     17.9     33.0        55-56           Can be observed when higher than 25 deg! 8 angles were missed due to weather.
27 Nov 2024  163899     19:00-23:00    0:17     15.1     78.1        289-309         Please avoid observing the target at 19:25-20:25 and 21:35-21:55 to avoid overlap! 2 x 16 angles
27 Nov 2024  Oljato     04:30-06:45    0:32     16.4     79.1-79.2   359-360         1 x 16 angles + 8 angles
03 Dec 2024  2020 XR    19:15-21:45    0:10     13.7     85.8-87.0   3882-3933       Use hitandrun script, please! 1 x 16 angles + 8 angles
03 Dec 2024  Florence   19:15-23:00    0:17     15.1     58.6        141-142         The number of frames has to be high because of the crowded field. 2 x 16 angles
03 Dec 2024  Oljato     05:15-07:00    0:22     16.6     87.4        347-350         -
07 Dec 2024  87684      19:30-22:15    0:40     17.5     50.4        307-309         Can be observed when higher than 25 degrees! Oljato can be submitted as a back-up target
07 Dec 2024  2020 XR    00:45-02:30    0:09     14.5     62.1-62.2   872-891         Can be observed when higher than 20 degrees!
14 Dec 2024  2020 XR    00:45-04:00    0:20     16.3     55.3        129-133         Start observing earliest at 1:25! Can be observed when higher than 25 degrees!
14 Dec 2024  Oljato     06:30-07:00    0:29     16.9     94.0        288-290         You can start the pointing before 6:30 UT if needed! 
22 Dec 2024  163899     19:15-22:30    0:13     15.8     89.9-89.0   215-220         Please avoid scheduling at 21:30-21:50
22 Dec 2024  2020 XR    01:00-03:15    0:36     17.4     48.8        49-53           If at all possible, schedule between 1:05 and 2:05! 
30 Dec 2024  87684      19:15-20:30    0:49     17.8     60.0        43-44           -
                              Back-up target for 87684 must be prepared! Preferably 2020 XR (although being low and a bit faint) but 4953, 163899 and Florence also work
06 Jan 2025  163899     19:30-21:15    0:30     16.8     103.1       142             -
06 Jan 2025  Florence   19:30-00:00    0:19     15.7     45.6-45.7   131-132         1 x 16 angles + 4 angles
10 Jan 2025  4953       19:30-21:00    0:49     17.6     46.7        75
                              Back-up target for 4953 must be prepared!
17 Jan 2025  163899     19:30-20:15    0:49     17.7     110.9-111.8 111-112         The 30 degree elevation requirement can be loosened if needed
                              Back-up target for 163899 must be prepared!
22 Jan 2025  87684      19:30-20:30    0:49     17.7     73.1-73.2   45              Observe as the first target of the night! The minimum elevation will be 25 deg. 
                              Back-up target for 87684 must be prepared! For example, Florence can be observed later at night.
28 Jan 2025       
03 Feb 2025  87684      19:45-20:45             17.6     86.0-86.1   56              Observe as the first target of the night! The minimum elevation will be 16 deg.
                              Back-up target for 87684 must be prepared! For example, Florence can be observed later at night.
08 Feb 2025  4953       19:45-20:30             17.1     56.7        100-101         Observe as the first target of the night!
                              Back-up target for 4953 must be prepared!
14 Feb 2025  87684      19:40-20:40             17.9     108.2-108.5 124             Point to the target right after focusing the telescope to achieve elevation of >6 deg for 50 minutes!
                              Back-up target for 87684 must be prepared!
19 Feb 2025  Florence   20:00-00:15             16.9     37.8        98-100       
26 Feb 2025  4953       20:00-20:45             16.6     70.9-71.0   112             Can be observed when higher than 20 deg!         
                              Back-up target for 4953 must be prepared!
06 Mar 2025  4953       20:05-20:35             16.5     81.6-81.7   112             Can be observed when higher than 20 deg!
                              Back-up target for 4953 must be prepared! For example, Florence can be observed later at night.
12 Mar 2025  4953       20:10-20:45             16.5     92.0-92.1   109             Can be observed when higher than 20 deg!
                              Back-up target for 4953 must be prepared! For exmaple, Florence can be observed later at night.
19 Mar 2025  4953       20:10-20:45             16.8     106.3-106.4 109             Can be observed when higher than 10 deg!
                              Back-up target for 4953 must be prepared! For example, Florence can be observed later at night.
25 Mar 2025  Florence   20:15-23:45             17.8     33.5        82-84           Observe as early as possible to avoid overlap!

The dates for 87684, 4953, Florence and Oljato are preliminary (since November).
There will be changes once new (most likely smaller) PHAs are discovered or when the already discovered PHAs become bright enough.
Potential known future/back-up targets to be observed in January and onwards include (103067) 1999 XA143, (137126) 1999 CF6, and (164121) 2003 YT1.

11 November 2024 : Mikael T. checked all the finder charts of the scheduled targets to check when the asteroids overlap the nearby stars.
This includes 87684, 163899, 2020 XR, Oljato, Florence, and 4953.

If not stated otherwise, the asteroids can be observed any time during the announced observation window.
All the dates have scheduled targets except January 28, but there is also space for additional targets in the following nights:
February 8, February 19, February 26, March 6, March 12, March 19.







 Daytime and twilight calibration instructions:



    

  •  Biases are taken as part of 
the automatic calibration script alfosc-calibs in the morning 
    

  •  NB! Afternoon dome-flats with the 
full polarimetry setup as follows (set off 
some afternoon time for this):

      
  
    1. In the Run-Selector, select the P68-803 Muinonen/Granvik program. This 
sets the fits header keywords and the data goes automatically to the right directory.
  
    2. power-on the telescope, place it and open mirror covers with the TCS
      commands alt 45 and o-m-c
  
    3. tcs.setup-tel-alfosc
  
    4. Place the halogen "FF lamp" under the telescope and plug in
  
    5. alfosc.carriage in 
  
    6. alfosc.wheels -s Calcite -f 76
  
    7. alfosc.focus-offset
  
    8. alfosc.resetxy; alfosc.polwin; alfosc.bin 2
  
    9. Take a test exposure to determine the exptime t  that gives between 300-400kADUs
  
    10. alfosc.linpolexpose 16 domeflat t 5 -nowindow; astrowakeup 
  
    11. When finished, do alfosc.carriage out, alfosc.resetxy, and
      alfosc.allopen 
  
    12. When setup is ready, reset focus: alfosc.focus-offset
  
    13.  Close mirror covers and park the telescope with the TCS commands c-m-c 
and zenith
  
    14.  In the dome disconnect the "FF lamp" and store it (NB! it can be hot!)
  
    15.  If it takes more than about 1 hour before your evening observations start, do 
power-off  on the TCS.

    

    
The obserations above will make 5 cycles of 16 angles each with exptime t.
    




  •  ALFOSC twilight skyflats for filter 
R (#76) with 2x2 binning as follows: (because of 2x2 bin, take these as the last of the 
standard sequence of broad-band flats: u' U z' B V R r' g' i i'). 


    1. alfosc.wheels -f 76; focus-offset
    
    2. alfosc.resetxy
    
    3. alfosc.bin 2
    
    4. alfosc.easyflat 3

    





 Observing instructions: 

    

    

  •  If you are not already using ALFOSC, go to the desktop where the ALFOSC
     Sequencer is running, and change the telescope settings with the command:
     
        tcs.setup-tel-alfosc
    


  •   Go to the directory
    
         cd ~/scripts/68-803
    
      List the available scripts 
    
         ls -lrt
    

All OBs to be observed will have tonight's date (i.e. start of the night)
      in their name. 
    
 Note that in addition to the target there can also be standard star polarimetry OBs

    



  •  Start the target script, when it tells you to do the pointing, go to
     another sequencer window and use either of these: 
    
     
     tcs.asteph -n targetname 
    
     tcs.asteph -m optimal-ll -n targetname     (for fast targets, rates > 100"/h) 
    
     
     tcs.asteph -m optimal-lr -n targetname (for fast targets, rates > 100"/h) 
    
     these commands connect to JPL Horizon to get the actual position and the rates
     at this UT time. 
     In the case of using the optimal modes you also get the
     best setting of the field-rotation to optimize guide star area for repositioning. 
    
     You can use either of the two. Try first the one that involves less turning of the rotator.
     See examples below. 
    


        
> tcs.asteph -n 68548
...
Your input target is                        -  68548
Your observatory is Nordic Optical Telescope, La Palma.
Retrieving data from JPL Horizons...
Data retrieved successfully from JPL Horizons.
The object being searched for is  68548_2001_XR31
Prefix for file names will be  2023-Oct-04.68548_2001_XR31
Today is  2023-10-04
Your computer says time is  11:53  UTC.
***************************
These tasks should be given to the TCS:
***************************
tcs.append-object 68548_2001_XR31-1 17 06 18.91 +78 39 35.7 2000.0 0.0 0.0 17.314
tcs.ag-off
tcs.guide-object 68548_2001_XR31-1
tcs.reposition-guide-probe 193.864 41.25260


> tcs.asteph -m optimal-lr -n K07S06Q
...
Your input target is                        -  K07S06Q
Your observatory is Nordic Optical Telescope, La Palma.
Retrieving data from JPL Horizons...
Data retrieved successfully from JPL Horizons.
The object being searched for is  2007_SQ6
Prefix for file names will be  2023-Oct-06.2007_SQ6
Today is  2023-10-06
Your computer says time is  10:11  UTC.
***************************
These tasks should be given to the TCS:
***************************
tcs.append-object 2007_SQ6-1010 03 20 02.18 +09 15 10.5 2000.0 0.0 0.0 17.709
tcs.ag-off
tcs.tcs-command "instrument-name ALFOSC ALFOSC-LR"; tcs.guide-object -f 57.173 2007_SQ6-1010
tcs.reposition-guide-probe 241.628 -374.546

    



  •  Copy and paste into the command line
the last four lines listed by the script - one by one.
    

  •  If this is a fast target, by the time
you have arrived, the target has already moved, and the FOV is small. It is a good
idea to repeat the steps again from the tcs.asteph command. 
    


When you get the prompt back after the 4th command (which sets the differential
RA/DEC rates), the guide star should be in the box, 
     the box should be close
to one edge of the TV screen, and the contrast value for guiding should be larger
than 1.0. The star+box will move across the TV screen at the non-sidereal rates. 
     
Differential tracking AND guiding is now running.

    


  •  Press return in the sequencer window
where the OB is runnning.  This will start the data acquisition. 
    
If the target is fast, i.e. RA/DEC rates > 100"/h, then the guide star will reach the
opposite end of the TV screen before the ~ 40 min long OB terminates. 
    

NB! You need to reposition before
the guide star reaches the opposite edge! 
     
This is done by repeating the 4th command, tcs.reposition-guide-probe .... 
before the edge is reached! 
    
TCS warning beeps are given when there is 120, 90, and 60 seconds left. 
    
Ideally, the telescope is not moved while the guide probe is repositioned, but if
many short exposures are used, it is wise to do this while the CCD is reading out.

    

For more general information on how this works, see the section "Moving Targets" in the ALFOSC Cookbook.







At the end of the night: 


 
    
 
  •  When all OBs are done (check also for standard 
star OBs with today's date ), please, close them. 
    
 
  •  Most observations are scheduled service mode. Only in the case of ToOs/SoftToOs, 
please, fill in the 
ToO or
SoftToO tracking log.
    
 
  •  Remember to run alfosc-calibs ALF***  in the morning, where the input parameter 
is the file prefix. 
    




Thank you for your help! 



 P68 tracking








 Program Tracking





Proposal
    68-803




Semester
   P69: 20240401 - 20241001




Principal Investigator
    Karri Muinonen,Mikael Granvik




Programme
    ESA S2P Program




Instrument
    ALFOSC




Time Allocation
    Follow-up and triggers in case regular obs. fails 




Total Nights
    1.0 




Type
    ToO+SoftToO




Notes
   Override, but should aim for (soft) triggers during Nordic service or Technical nights




Total Time Spent
    (hh:mm)
    
   










        Proposal
        Date
        Time
        Type
        Targets
        Files
        Comments 	
        Status
        








Empty table: no tracking data available (yet)
 


The above information is collected from the ToO/Mon reports that have been created by the observer.

Should any of the observations have been carried out using the OB system, you will find additional information 
HERE
Back to top Last modified: November 20 2024