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Parkes Schedule File Creator: Position Switching

Project:
Observer initials:
Receiver:
Central Frequency:  MHz
Correlator Configuration:
Correlator Cycle Time:
Doppler Tracking: enabled    disabled
Velocity Frame: LSR-KINEMATIC    LSR-DYNAMIC   Barycentric   Topocentric
Integration time per ON Position: s
Spectral averaging interval: s
ON-OFF Pattern: symmetric (OFF-ON-ON-OFF)    non-symmetric (OFF-ON-OFF-ON) disabled (SB option)
Duration for each source: min
Coordinate system: B1950 J2000 Galactic
Offset of the ON relative to source: RA/GLONG:    DEC/GLAT: 
Reference (OFF) position: relative to ON      absolute position
RA/GLONG:    DEC/GLAT: 
Source List:

To refresh the screen using the default entries, press SHIFT and click the 'reload' button simultaneously.

This output should be saved on your local computer (.sch) and then uploaded to the Parkes system upon your arrival.


Project

The project number assigned to your proposal.

Example: P345

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Observer Initials

Initials or short name of the observer(s).

Example: ZOZ

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Correlator configuration

Select a correlator configuration from the menu. Only a few are listed and if yours is not listed, select NULL and enter it once you arrive at the observatory. A full list of supported modes is available from the Parkes Correlator Guide.

DFB3/DFB4 configurations with "tb" indicate time-binning modes. For these, the number of time bins (set on the TCS GUI) must be at least 4 and at most 32. As an example, if you want 1 second sampling with sdfb3_tb16_16_8192, you would set the number of time-bins to 16.

Other DFB3/DFB4 configurations are "spectrometer" modes and require a cycle-time at least 4s and the number of time-bins set to 1.

Example: sdfb3_64_1024

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Correlator cycle time

Select the number of seconds per correlator cycle. If using the Multibeam Correlator, the default is 5 seconds per integration. If using DFB3 or DFB4, the cycle time depends on the configuration, (especially if you are using a time binning mode) but must be at least 4s. Example: 5

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Receiver & Central Frequency

The reciever and centre frequency of your observations. If Doppler tracking is enabled, the frequency here will be interpreted as the rest frequency of the observed line. If Doppler tracking is disabled the frequency here would be the actual observing frequency (sky frequency).

Make sure your frequency is within these limits (in MHz):

H-OH 1090 2000
MULTI 1250 1550
GALILEO 2000 3000
10CM (1050CM package) 2500 3700
METHMB 5800 7000
MARS 7900 9100
KU-BAND1200015000
13MM 1600026000

Example: 1420.405

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Doppler Tracking

Enable/disable Doppler tracking. Note that this only adjusts the centre frequency, it does NOT continuously track the Doppler shift during an observation.

Example: disabled

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Velocity Frame

The reference frame of the source, LSR-KINEMATIC, LSR-DYNAMIC, Barycentric or Topocentric. For Galactic work, LSR-KINEMATIC is more commonly used than LSR-DYNAMIC. For Extra-Galacitc work, either TOPOCENTRIC or BARYCENTRIC are used.

* Note: If Doppler tracking is disabled and no radio velocity is specified (also recommended) then you must adjust your sky frequency to account for the velocity of both the source (LSR or barycentric) and the velocity of the observatory relative to the rest frame. An online tool is available Frequency Calculator to calculate this adjustment.

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Integration time per ON position

Integration time on your source in seconds for each individual track. The corresponding reference (OFF) track will be observed with the same integration time. Don't make this value too large (say larger than a couple of minutes) as the sky conditions may change while you are on source.

Example: 60

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Spectral averaging interval

Number of seconds to average spectra over before writing to disk. Default is no averaging (1s). However, for high data rates averaging is recommended.

Example: 1

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ON-OFF Pattern

Two different patterns to are provided: The symmetric pattern will perform observations as OFF-ON-ON-OFF while the non-symmetric pattern will alternate between the the ON and the OFF position like OFF-ON-OFF-ON... The symmetric pattern has the advantage of reducing driving times, whereas the OFF integration of the non-symmetric pattern can be chosen to be toward the same patch of sky as the ON position. For the latter you may provide the reference position relative to the ON (see below) by selecting an RA offset of the reference position equal to the negative of the integration time. Note it is possible to disable this by selecting the "disabled" option. The schedule only only contain ON positions.

Example: symmetric

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Duration of Schedule

Total duration of the observing pattern in minutes. This 'total time' does not include driving times. This number determines the number of ON-OFF pairs. For example, if you wish to observe ON-source for 240 seconds, to observe the ON/OFF positions once (regardless of the pattern chosen), you would enter 8 minutes. To obtain four ON/OFFs, enter 16 minutes and so on.

Example: 15

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Coordinate system

The coordinate system of your coordinates. You may choose between equatorial (J2000 or B1950) or Galactic coordinates. Please take care of the format: Equatorial, RA: hh:mm:ss DEC: dd:mm:ss, Galactic GLON: ddd.xxxxx GLAT: dd.xxxxx. It is your responsibility to input the coordinates in the right format.

Example: J2000

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Offset of the ON relative to source

The location of the ON position relative to the source coordinates. Generally not used.

Example: RA: 00:02:00  DEC: -00:10:00
will shift the target position 2 time minutes to the east and 10 arcseconds to the south.

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Reference (OFF) position

The position of the reference (OFF) integration. You may choose between relative and absolute positioning. The relative position refers to the position you provided for the the source coordinates. Alternatively, you may provide an absolute position for the OFF integration. Depending on the coordinate system you choose, the coordinates must be given in sexagesimal or decimal format.

Example:  absolute   RA:  12:33:15.3   DEC:  -72:54:04.8

Example:  relative   RA:  00:00:00.0   DEC:  -00:15:00 (offset of -15 arcmin in dec)

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Source List

Specify your source list here, one per line. Format is Name, RA/GLONG, DEC/GLAT and VELOCITY. For coordinates, ensure you select the appropriate Coordinate system above. If using doppler tracking (i.e., your velocities are non-zero), ensure you set the correct frame above. Note that radial velocity information provided here will be ignored if Doppler tracking is disabled.

Example: AG356.48+0.19 17:36:13.8088 -31:49:06.713 -50

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Original: Juergen Ott (11-July-2005)
Modfied: Kate Brooks (10-Mar-2009)
Adapted for Parkes: Stacy Mader (17-July 2009)
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