Instructions for the GMVA session on Oct. 8-12, 2020 
******************************************************

Ver. 1: 24.9.2020

Fringe Tests:
-------------

The fringe test is done only in Europe. 

         f202a: day 282 282-1200(08/10) -> 282-1500(08/10)  Pv Eb Ys On Mh

The vex files for the fringe test are here:

         ftp://ftp.mpifr-bonn.mpg.de/outgoing/p459kri/3mmoct20/sched/


Main Session:
-------------

All experiments are recorded with the new GMVA setup (4 Gbps, DDC mode, dual pol).

This sessions consists of 3 parts with name:  c202a, c202b, c202c

The time allocation is as follows (all times in UT):
(see block schedule: https://www3.mpifr-bonn.mpg.de/div/vlbi/globalmm/sessions/oct20/MMschedule.asc )

        Exp.                    start (UT)         stop (UT)
        c202a               282-1800(08/10) -> 284-0054(10/10)  Pv Eb Ys On Mh + VLBA + KVN

        c202b               284-0100(10/10) -> 285-2120(11/10)  Pv Eb Ys On Mh +KVN
        c202b               284-0100(10/10) -> 286-0325(12/10)  VLBA 

        c202c               285-2215(11/10) -> 286-0640(12/10)  Pv Eb Ys On Mh
        c202c               286-0340(12/10) -> 286-1200(12/10)  VLBA

Note that c202c has a different LO setting (87300 MHz) !!!


Schedule Location:
------------------

      c202a:      http://www.vlba.nrao.edu/astro/VOBS/astronomy/oct20/c202a
      c202b:      http://www.vlba.nrao.edu/astro/VOBS/astronomy/oct20/c202b
      c202c:      http://www.vlba.nrao.edu/astro/VOBS/astronomy/oct20/c202c

You can elso retrieve the schedule from the the GMVA website 
(http://www.mpifr-bonn.mpg.de/div/vlbi/globalmm/) 
via the link -> Session -> Observing Session for Oct 2020 -> all files from SCHED 
The link on the GMVA web site points to /astronomy at the VLBA (which is the same as above).

If DRUDG has problems with the *.vex files, you can use the *.vex_noptg files instead.
The files ending *noptg DO NOT contain the SiO pointing scans (which only the VLBA needs). 


Disks:
-------

Most station have received disk modules for the GMVA session. These 
modules were conditioned and read/write tested at the correlator. 
The modules belong to the GMVA pool and must be used only for these 
GMVA observations. 

Before recording the first scan on a module, the modules MUST be erased using the 
mk5erase (VSN) command. This command should be applied only once before 
the Session starts. It  *NEVER* should be applied during the session, because
this will erase all previously recorded data.

Approximate STATION DISK USAGE SUMMARY:

STATION SCAN SUMMARIES:
  Station  Control   Scans   Scan   Record  Record   Gbytes
                            Hours   Hours   Scans
  VLBA_FD    VLBA     645   52.55   52.55     645    97485.
  VLBA_NL    VLBA     642   52.07   52.07     642    96583.
  VLBA_OV    VLBA     640   51.97   51.97     640    96403.
  VLBA_PT    VLBA     645   52.59   52.59     645    97547.
  VLBA_BR    VLBA     637   51.54   51.54     637    95599.
  VLBA_KP    VLBA     643   52.35   52.35     643    97114.
  VLBA_MK    VLBA     489   39.79   39.79     489    73803.
  VLBA_LA    VLBA     645   52.59   52.59     645    97547.

  KVNYS      VEX      163   17.20   17.20     163    31906.
  KVNUS      VEX      163   17.20   17.20     163    31906.
  KVNTN      VEX      163   17.20   17.20     163    31906.

  EFLSBERG   VEX      413   36.97   36.97     413    68573.
  ONSALA60   VEX      411   36.78   36.78     411    68233.
  YEBES40M   VEX      407   36.83   36.83     407    68326.
  PICOVEL    VEX      396   35.87   35.87     396    66533.
  METSAHOV   VEX      397   35.13   35.13     397    65172.

7mm-only:
  VLBA_HN    VLBA     175    9.40    9.40     175    17437.
  VLBA_SC    VLBA     168    9.00    9.00     168    16695.



Automatic reference pointing (VLBA-only) and vex files:
-------------------------------------------------------

For the VLBA automatic reference pointing on SiO masers at 7mm is implemented in
the schedule. 


7mm observing:
--------------

Experiments c202a and c202b observe also at 7mm (VLBA only).
c202c does not observe at 7mm.


Recording mode:
---------------

All experiments are recorded using the tunable DDC mode of the RDBE at 4 Gbps.
The VLBA records using 4x128 MHz, the European station record at 8x64 MHz.
The setup is described here:

https://deki.mpifr-bonn.mpg.de/GMVA/GMVA_Setups


Polarisation:
-------------

Dual polarisation (LCP/RCP) is requested. Those stations which have only single
polarisation should record LCP and connect both IF-inputs of the DBBC to LCP.
ALMA should record both linear polarisations (H, V).


Phasecal:
---------

For c202a and c202b  phasecal should be ON (where possible).
For c202c phasecal *MUST* be off (spectral experiment).


Calibration: During the experiments, please perform regular antenna- and
------------ system-temperature measurements in gaps between VLBI scans. 
             Please also provide measurements of atmospheric opacities vs. time.
             Please provide K/Jy values and updated gain-elevation curves. 

For Europe: If you cannot measure Tsys continuously (every 60-120 sec), it should be measured 
            before *AND* after each VLBI scan. Please modify your station procedures, accordingly.
            Please insert the correct CALTEMP in your station procedure. In gaps between VLBI scans, 
            antenna temperature measurements of the VLBI sources should be done (cross-scans or on-offs).


Disk usage:
-----------

Each station has received disks from Bonn. All parts of this GMVA run
should be recorded on these diskpacks. 

Shipping:
---------
After observation please send the recorded disks to the Bonn correlator.


LOGS:
-----
After observation please place the logs, ANTAB files and
calibration information on the EVN server using the following address:

ftp vlbeer.ira.inaf.it  (ftp://vlbeer.ira.inaf.it/vlb_arc/ftp/vlbi_arch/oct20/)
user: evn
passwd:  ask us
cd vlbi_arch/oct20
put ....
exit

You can also e-mail the logs to tkrichbaum@mpifr.de, who will put it on 
the ftp-server.


Contact Adress:  Don't hesitate to contact me in case of questions.

--------------------
Thomas P. Krichbaum                       
Max-Planck-Institut fuer Radioastronomie 
Auf dem Huegel 69                        
D-53121 Bonn / Germany

E-mail: tkrichbaum@mpifr.de
Tel.:   (Germany +49)-228-525-295 office, 
        (        +49)-2257-301-155 during observations

