Single Dish Intents/Modes/Use Case comparisons

Purpose: Compare intents and modes particularly with regard to SD data
----------------------------------------------------------------------

The intent and state information in SDFITS, the ASDM and MS are as follows:


        OBSMODE - 8 characters
                type=LINE, CONT, PULS + mode (PSSW, FQSW, BMSQ, PLSQ, LDSW,
                TLPW, etc). Writers encouraged to use FITS comments to document
                the modes)

                              
        [Main]                          [Main]
                StateId                         STATE_ID
                configDescriptionId
                stateId
        [ConfigDescription]
                switchCycleId
        [Scan]
                ScanIntent
        [State]                         [State]
                obsMode                         OBS_MODE(PROC:SWState:SWtchsig)
                obsIntent
                -
                calLoadNum                              CAL (missing in ASDM)
                sig                                     SIG
                ref                                     REF
                (weight)
        [SwitchCycle]
                weightArray
                offsetArray
                freqOffsetArray
                numStep
                                                        SUB_SCAN(=NRAO_PROCSEQN)
                                                        (NRAO_GBT_PROCNAME)
                                                        (NRAO_GBT_PROCSIZE)
                                                        (NRAO_GBT_PROCSEQN)
---

Some points to note:
  1) The MS has a slightly different event structure than the ASDM. In
     particular, it has only SCANS and INTEGRATIONS. One could consider
     SUBSCANS to be collections of INTEGRATIONS within a SCAN (e.g., sets
     of repetitions of the four calibration phases); however these are not
     marked as such.
  2) The MS SUB_SCAN column is used to denote links between SCANs rather
     than a data structure under the SCAN level. Currently it is used
     in single dish analysis to associate the SIG/REF pairs of a
     position switched scan sequence and to associate the rows of an OTF
     map where SCAN is one row/raster of the map.
  3) For the MS, the SOURCE can change at the SCAN level (though it is
     not necessary (i.e., you can have repeated scans on the same SOURCE).
  4) The ASDM strucures are (currently) defined such that:
         a) A SOURCE can change at the SCAN level.
         b) A FIELD can change at the SUBSCAN level.
        Thus, an OTF map will be a collection of SUBSCANS for the ASDM
        composing a single SCAN, while it is a collection of SCANS for the
        MS (currently).
--------------------------------------------

Use Cases:

NOTE: In the examples below, we use GBT data as a representative case; the GBT
allows insertion of a calibration source in the signal path as indicated by the
CAL boolean; this is not duplicated in the ALMA example as it is unlikely to be
a needed capability of the system. ALMA will use a robotic arm for insertion
of hot/cold loads as required and so is essentially a distinct type of SCAN.

 Frequency Switched scan
--------------------------
[MAIN]                          | [STATE]
SCAN_NUMBER STATE_ID            | OBS_MODE              CAL     SIG     REF     SUB_SCAN
1           0                   | TRACK:FSWITCH:FSW01   0       0       1       1
1           1                   | TRACK:FSWITCH:FSW01   1       0       1       1
1           2                   | TRACK:FSWITCH:FSW01   0       1       0       1
1           3                   | TRACK:FSWITCH:FSW01   1       1       0       1

*equivalent representation in the ASDM*:

 Frequency Switched scan
------------------------------
[Main]                          |  [SwitchCycle]
SCAN_NUMBER configDescriptionId |  numStep weightArray offsetArray freqOffsetArray
1           1                   |       2       [1,1]       [0,0]       [0,2.5]
[ConfigDescription]             |
            switchCycleId       | *if beam-switched data*
            1                   |
[Scan]                          |  [SwitchCycle]
            scanIntent          |  numStep weightArray offsetArray freqOffsetArray
            TARGET              |       2       [1,1]       [0,180]     [0,0]
[State]                         |
            obsMode             |
            FSWITCH             |

================================================================================


 Position Switched Set of scans
-----------------------------------
[MAIN]                  [STATE]
SCAN_NUMBER STATE_ID    OBS_MODE                CAL     SIG     REF     SUB_SCAN
1           0           OFFON:PSWITCHON:TPWCALSP  1     1       0       1
1           1           OFFON:PSWITCHON:TPWCALSP  0     1       0       1
2           2           OFFON:PSWITCHON:TPWCALSP  1     1       0       2
2           3           OFFON:PSWITCHON:TPWCALSP  0     1       0       2

*equivalent representation in the ASDM*

 Position Switched scan
-----------------------------
-----------------------------
[MAIN]                  [STATE]
SCAN_NUMBER STATE_ID    OBSMODE                 SIG     REF
1           1           TRACK                   1       0
1           2           TRACK                   0       1

================================================================================


 OTF map
----------
[MAIN]                  [STATE]
SCAN_NUMBER STATE_ID    OBS_MODE                CAL     SIG     REF     SUB_SCAN
1           0           RALONGMAP:FSWITCH:FSW01 0       1       0       1
1           1           RALONGMAP:FSWITCH:FSW01 1       1       0       1
1           2           RALONGMAP:FSWITCH:FSW01 0       0       1       1
1           3           RALONGMAP:FSWITCH:FSW01 1       0       1       1
2           4           RALONGMAP:FSWITCH:FSW01 0       1       0       2
2           5           RALONGMAP:FSWITCH:FSW01 1       1       0       2
2           6           RALONGMAP:FSWITCH:FSW01 0       0       1       2
2           7           RALONGMAP:FSWITCH:FSW01 1       0       1       2
...
n
================================================================================

Single dish intents/modes:

(GBT Example - Modes)
14 Observing Modes
        Position Switched - Single Beam(4),
        Position Switched - Dual Beam
        Total Power Track
        Frequency Switched Track
        Beam Switched Track
        Point Map (Grid Mapping)
        OTF Map
        Continuum Map
        ---
        Pointing Corrections
        Focus Corrections
        Tipping Scan (SkyDip)
        VLBI
        Pulsar
        Radar
                                         MS
                         ---------OBSERVING_MODE--------------
                        /                                      \
DISH-gms function                                                       (STATE_IDs=
        Scan    Object  Proctype        SWState         SWtchsig        Phases)         Procseqn        Procsize(in scans)
        ----    ------  --------        -------         --------        -----------     --------        ------------------
                        RALongMap       NONE            TWNOCAL         1                               # of rows
                        DECLatMap       FSWITCH         TPWCAL          2/position                      # of rows
                        Track           PSWITCHON/OFF   TPWCALSP        2/position                      1
                        OffOn           BSWITCH         FSW01           4                               2
                        OnOff                           FSW12           4a                              2
                        OffOnOff                        FSW0102         8                               1

ASDM Consolidated/Proposed Intents
__________________________________
QUESTIONS:
  1) Are the above/below correct?
  2) Do we require more intents than listed - can we fill them in now?
  3) Is subScanIntent really required?
     3a) Is the subScan concept still rewarding?

SBSummary SBSummary SBSummary         Scan              STATE           Subscan
SBIntent  SBType    Observation Mode  scanIntent        obsmode         subScanIntent
--------  ------    ----------------  ----------        ------          -------
User      Standard  Single Field \    TARGET                            TRACK
          Expert    Mosaic       /    PHASECAL          PHASECAL
          Observatory                 AMPLICAL          AMPLICAL
                                      BANDPASS          BANDPASS
                                      POLARIZATION      POLARIZATION
                                      PHASECURVE        PHASECURVE
                    Single Dish       TARGET            TRACK
                                                        FSWITCH
                                                        BSWITCH
                                      TARGET            OFFON           ON
                                                                        OFF
                    OTFSingleDish     TARGET            RALONGMAP       FSWITCH
                                                        DECLATMAP
                    OTFMosaic         TARGET
                                        ?
------------------------------------------------------------------------------------------------------------------
                                Other CALIBRATIONS
                                      ------------
                                      CALIBRATION                       CALIBRATION
                                      FOCUS             PATTERN         FOCUS_SEQN
                                      HOLOGRAPHY        HOLOGRAPHY      HOLOGRAPHY
                                                        RASTER          RASTER
                                      POINTING          CROSS           POINTING_SEQN
                                                        5-POINT
                                                        DRIFT
                                      ATMOSPHERE                        ATMOSPHERE
                                      POINTINGMODEL                     POINTING_MODEL
                                      DELAY                             DELAY
                                      ANTENNAPOSITIONS                  ANTENNAPOSITIONS
                                      SKYDIP            PATTERN         PATTERN-SEQN

                                      LAST                              LAST
                                      OFFLINE                           OFFLINE


-- JosephMcMullin - 08 Nov 2006
Topic revision: r1 - 2006-11-08, JosephMcMullin
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