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Parkes Schedule File Creator: On-the-Fly (OTF) Map

Project:
Observer Initials:
Receiver:
Frequency Switching: enabled    disabled
Parallactic angle tracking:
Beam position angle:  degrees
Central Frequency:  MHz
Correlator Configuration:
Correlator Cycle:
Doppler Tracking: enabled    disabled
Radial Velocity: km/s    Frame: LSR-KINEMATIC    LSR-DYNAMIC    Barycentric   Topocentric
Spectral averaging interval: s
Coordinate system:   B1950  J2000     Galactic
Source Name:
Source Position:RA/GLon:     Dec/GLat: 
Reference (OFF) Position Type : absolute position
Reference (OFF) Position Value: (absolute coordinates separated by a space)
Map width: arcmin (only square maps supported at this time)
Scanning direction: RA/GLONG     DEC/GLAT
Starting Point: north-west     north-east     south-east     south-west
Number of scanning rows per OFF: 2 1
Nyquist Frequency (optional): MHz
Time spent on OFF scans (optional):s
Spacing between rows (optional):arcsec
Beam Size (optional):arcsec
Proper motion of the source(optional): arcsec/hour

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 observing computers when you arrive.


Project

The project number assigned to your proposal.

Example: P345

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Observer

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 more than 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 is usually set to 4 or more.

Example: 4

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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 concentric 2600 3600
METHMB 5800 7000
MARS 7900 9100
KU-BAND 12000 15000
13MM 1600026000

Example: MULTI 1420.405

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Frequency switching

Enable frequency switching, with the switched IF separated from the main IF by some number in MHz (+ and - signs acceptable). Beware not to have an offset switch out of band.

Example: -4.5

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Parallactification mode (Multibeam receivers only)

Enable receiver rotation with Multibeam receivers. For single-beam receivers, set this to disable. The modes are: In the STEPPED mode, the platform is rotated just before a scan starts, so it is exactly in the right orientation at mid-scan. BEAMTRK does a position tweak every 5 seconds during a scan, ensuring that the platform stays close to the scan axis all the time (good for scans near the south pole). BEAMTRK is essentially the same as CONTINUOUS, but with the addition that it does the hard work of determining the actual track on the sky during a scan, and positioning the platform relative to that axis (rather than the latitude lines, for example).

Example: disable

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Position/Feed angle

Rotate the receiver by a given angle, in degrees. This is only available with Multibeam receivers. For single-beam receivers this should be set to "0".

Example: 19.1

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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. For observing with MOPS it is recommended that Doppler tracking be disabled.

Example: disabled

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Radial Velocity

The radial velocity of your source. Also choose the reference frame, LSR-KINEMATIC, LSR-DYNAMIC, Barycentric or Topocentric. The radial velocity information provided here will be ignored if Doppler tracking is disabled.

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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Spectral Averaging Interval

Number of seconds to average spectra over before writing to disk. Default is no averaging (1 s).

Coordinate system

The coordinate system of your coordinates. You may choose between equatorial (J2000 or B1950) or Galactic coordinates.

Example: J2000

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Source Name

Specify the name of your source here. If left blank the source name defaults to "source".

Example: Orion

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Source Position

Please provide the source coordinates in the specified coordinate system here. This determines the centre of the on-the-fly map. Please take care of the format: Equatorial, RA: hh:mm:ss DEC: dd:mm:ss, Galactic GLON: ddd.xxxxx GLAT: dd.xxxxx.

Example: RA: 23:41:32  DEC: -82:43:09

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Reference (OFF) Position Type

You may choose only absolute positioning for the reference position.

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Reference (OFF) Position Value

The position of the reference integration (2 values separated by a comma). Please take care of the format: Equatorial, RA: hh:mm:ss DEC: dd:mm:ss, Galactic GLON: ddd.xxxxx GLAT: dd.xxxxx.

Example 1:  12:33:15.3, -72:54:04.8   
Example 2:  366.4988, -54.0000   
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Map Width

The size of the map in arcmin. Only square maps are supported at this stage. The maps always have an odd number of rows so that one row passes through the map centre. Consequently the final map width may vary from what you specified here.

Example: 5

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Scanning direction

Scanning direction of the map. You may choose to perform your map along RA/GLONG (i.e. horizontal direction) or along DEC/GLAT (vertical direction). Scanning at arbitrary angles is currently not supported.

Example: RA/GLON

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Starting point

Starting point of the map. Values may be the north-eastern, north-western, south-eastern, or south-western corner.

Example: north-east

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Number of scanning rows per OFF

Number of OTF rows before returning to the OFF position. You may choose 1 row for large maps (say more than 2 arcmin in size) and 2 for small maps.

Example: 1

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Nyquist Frequency:

This frequency value (in MHz) is used to calculate the Nyquist sampling rate for the scanning. Default is the value given in Observing Frequency.

Example: 88000

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Time spent on OFF scans:

Time spent on OFF scans in seconds. Default is calculated from the time spent on each row. Please seek advice from support staff if you require no reference scans.

Example: 120

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Spacing between rows:

Spacing in arcsec betwen rows (orthogonal to the scanning direction). Default is calculated from the Nyquist frequency using an extra 0.9 oversampling factor and a 2" guard band to mitigate against tracking errors.

Example: 40

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Beam Size

Beam size in arcsec (FWHM). Default is calculated from the Nyquist/Observing frequency with a Nyquist sampling rate (lambda/2D, where D=55m or D=64m). This value is then used to determine the scan rate.

Example: 40

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Proper Motion

(Note: This option has not been tested.)Proper motion of the source, in arcsec/hour in the directions of specified coordinate system (RA/Dec or GLON/GLAT). Two values separated by white space. Default is zero. Note: Proper motion tracing is inexact and based on an estimate of how time passes during the map. The map centre is updated at the beginning of each scan. You should give as the map centre the position of the source at the start of the map. Coordinates and proper motions of the planets are available on JPL's HORIZONS website.

Example: 10.2 -3.5

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