This is a source file to carry out continuum radiometry using the stepping and scanning techniques for comparison, on a flux calibrator at four frequencies as it crosses the zenith meridian. The catalogue that it refers to follows it. This type of file would typically be scheduled in to calibrate other observing.
JJ: Note that the RA and DEC keywords in the catalogue will be used to define a source-centred coordinate system. Because "SCANTYPE=STEP" the "PROJTYPE" defaults to "TAN", i.e. no need to worry about "Cos Dec" corrections in steps. Until Steer is modified the TAN coordinate projection will be approximated by CAR.
SETUP OBSERVER G.D. NICOLSON PROJECT flux calibration PROPOSAL 1999.001 CATALOG calibrators.cat OUTFILE calibrator.data // output file for all scans CONF 1666NA RESTFREQ 1666E6 // use 18cm receiver at 1666MHz INSTRUME NA // use noise-adding radiometry WEATHER cloud ENDCONF CONF 2300NA RESTFREQ 2300E6 // use 13cm receiver INSTRUME NA // use noise-adding radiometry WEATHER cloud ENDCONF CONF 5000DI RESTFREQ 5000E6 // use 6cm receiver INSTRUME DICKE // use dicke radiometry, beam-switching mode WEATHER clear ENDCONF CONF 8500DI RESTFREQ 8500E6 // use 3.5cm receiver INSTRUME DICKE // use dicke radiometry, beam-switching mode WEATHER clear ENDCONF DEFCONF 1666NA 2300NA 5000DI 8500DI // use all 4 conf blocks as default ENDSETUP OBJECT 0915-11 // use the definitive flux calibrator SOURCE 1 SCANTYPE STEP // first we step at all frequencies STEPSEQ FNNCAL, HPN, ON, HPS, FNS, FNE, HPE, ON, HPW, FNW HALIST 0h00m // starting at HA = 0 hour JJ notation OBJECT 0915-11 SOURCE 2 // same object name so add a SOURCE ident. SCANTYPE SCANPNT // now we do cross-scans at all frequencies HALIST 1h00m // starting at HA = 1 hour in postfix notation
The continuum calibrator catalogue calibrator.cat
, would have
multiple entries like this:
COMMENT fluxes of these calibrators are computed using: COMMENT Log(S/Jy) = C1 + C2*log(F/MHz) + C3*(log(F/MHz))**2 REFERENC Ott et al. (1994) AA 284, 331. OBJECT 0915-11, 3C218, Hydra A, HydA COORDSYS EQUATORIAL EQUINOX 1950.0 RA 09 15 41 DEC -11 53 06 OBJFLUX 4.729 -1.025 +0.0130 // coefficients C1, C2, C3 for flux calc CALRANGE 1408E6 10550E6 // valid frequency range for computing flux COMMENT galaxy, size 47" * 15"
With appropriate programming, using the information in the catalogue the calibrator flux density at each frequency used can be written to the output file for use in calibrating the day's observing, together with the observational data.
This demonstrates the use of some of the scheduling options. Note that the interval between binned samples for the output is adaptively set to match the beamsize, with say 12 points per halfpower beamwidth, by the standard drift scan software (or SYPARM), so is not specified. Parameters used in the example are "inspired" by those found in HP/OBCIR.
This input file would set up three drift scans per day at 3.5cm, starting one day before the expected transition date through two days after the transition date. The transition dates are calculated from the STRTDATE and first INCREMNT parameter.
All post-observing data processing such as subtracting off a background, fitting a polynomial to the baseline, measuring peak heights by Gaussian fitting are done by standard analysis programs using the data recorded in the disk file. These processes could be done by a LINES command file, for example.
JJ: Because "SCANTYPE=DRIFT" the default "PROJTYPE" is "NONE" and "X" and "Y" are preset to "RA" and "DEC".
SETUP OBSERVER G.D. NICOLSON PROJECT monitor flux of flaring binary star Circinus X-1 PROPOSAL 1999.002 COMMENT define all receivers of interest for Cir X-1 in setup, COMMENT `useconf' specifies those wanted for each object COMMENT non-flaring currently so only use most sensitive receiver, 3.5cm CONF 13 // configuration block name RESTFREQ 2300E6 // use 13cm receiver INSTRUME NA // use noise-adding radiometer pair SCANDIST 1.85d // scan length at 13cm, in degrees STRTTIME SUNSET // JJ alternative to NIGHTOBS ENDTIME SUNRISE // JJ ENDCONF // end of configuration block CONF 6 // new configuration block name RESTFREQ 5000E6 // use 6cm receiver INSTRUME DICKE // use dicke radiometer, beam-switching mode SCANDIST 1.85 // scan length at 6cm OR SUNDIST 45 // observe at 6cm if > 45 deg from Sun // implicit ENDCONF as new CONF follows CONF 3.5 // new configuration block name RESTFREQ 8500E6 // use 3.5cm receiver INSTRUME DICKE // use dicke radiometer, beam-switching mode SCANDIST 1.082d // scan length at 3.5cm SUNDIST 30d // observe at 3.5cm if > 30 deg from Sun RCVNAME 3.5 // implicit ENDCONF as ENDSETUP or OBJECT follows ENDSETUP // blank line to be pretty OBJECT CIR X-1 // start of scan definition COORDSYS EQUATORIAL // just so EQUINOX 1950.0 // B1950 coordinate equinox RA 229.201 // RA in decimal degrees DEC 303.013 // Dec in decimal degrees SCANTYPE DRIFT // drift scan STRTDATE 2443075.87 // 1976 d 299.37; JD avoids leapyear problems // one day before flare epoch ENDDATE 2443078.87 // two days after flare epoch, giving 3 days of // observations INCREMNT 16.5768 // period (ignore Pdot) OUTFILE cirx1 // output file name for all scans HALIST -3h30m 0h +3h30m // scans at three hour angles USECONF 3.5 // only use config named 3.5 REPEATS 2 // do two scans for comparison WEATHER clear // observe only in clear weather ENDOBJ // (redundant) end of object scan definition
This is how we would probably implement Sarah's mapping technique, not to be confused with Skymap. Notice that there is no mention of an ST or RA, so the scheduler will have to deal with galactic coordinates. Each scan is written to a separate file to aid data editing.
SETUP OBSERVER J.L. JONAS OBSLOCAL G.D. NICOLSON PROJECT galactic plane map at 3.5cm PROPOSAL 1999.003 COORDSYS GALACTIC // ###JJ### // ###JJ### no need for EQUINOX CONF 8000NA RESTFREQ 8000E6 // 3.6cm map ###JJ### INSTRUME NA // use noise-adding radiometer pair // ###JJ### presumably this will set up // "Beam A" feed offsets??? JQ ? ENDCONF SCANTYPE SCAN PROJTYPE TAN // ###JJ### default would be "CAR", but // we want to compare with optical image GLON 270d // Galactic coordinated of map centre GLAT +20d // LONGPOLE 0.0 // ###JJ### this is the default field // rotation, so not strictly needed HALIMIT 3h0m // ###JJ### no need for constant HA start, // only reasonable elevation // ###JJ### no generic OUTFILE WEATHER clear // observe only in clear weather DEFCONF 8000NA ENDSETUP // ###JJ### new scan definitions OBJECT SCAN001X OUTFILE mapjj.x.1.fits // individual output file STARTX -5d // new way of specifying scan start//stop STARTY -5d // relative to special point (map centre) STOPX -5d // default would be STARTX STOPY +5d SCANTIME 100 // scan at (5+5)/100 = 0.1 deg/sec // DEFCONF automatically paster in OBJECT SCAN002X OUTFILE mapjj.x.2.fits // individual output file STARTX -4.9d // new way of specifying scan start/stop STARTY +5d // relative to special point (map centre) STOPX -4.9d // default would be STARTX STOPY -5d // scan spacing is 0.1 degree SCANTIME 100 // scan at 10/100 = 0.1 deg/sec // DEFCONF automatically pasted in etc OBJECT SCAN001Y OUTFILE mapjj.y.1.fits // individual output file STARTX -5d // new way of specifying scan start/stop STARTY -5d // relative to special point (map centre) STOPX +5d STOPY -5d // default would be STARTY SCANTIME 100 // scan at 10/100 = 0.1 deg/sec // DEFCONF automatically pasted in etc
This is part of an input file to show the coordinate specification for a doing a scan at constant elevation, from JJ.
#JJ#: This example (and your drift scan example) show up an interesting problem: how do you scan through a target specified in a celestial coordinate system using geocentric coordinates to specify the scan. In the above example I have made no attempt to scan through a target, rather assumed the required criterion was to scan at a given elevation with no real regards to the celestial coordinate requirements.
Note: This needs a preceding SETUP section to give all mandatory keywords for this single scan.
OBJECT FRED const elevation // object for scan COORDSYS HORIZON // not strictly needed - AZ, EL unique AZ 0 // use "native" az/el coords EL 0 // PROJTYPE NONE // SCANTYPE SCAN // active scan in galactic coordinates STARTX 0 // scan start azimuth STOPX 180 // scan end azimuth STARTY 40 // constant elevation STOPY 40 // of 40 deg SCANTIME 100 // scan time in seconds OUTFILE jjconel
Partial input file for a declination scan, from JJ.
Note: This needs a preceding SETUP section to give all mandatory keywords for this single scan.
OBJECT Sgr A declination scan// object for scan COORDSYS EQUATORIAL // not strictly needed - RA, DEC unique EQUINOX B1950 // needed PROJTYPE NONE RA 17 42 26.6 // = GLON 0.000 DEC -28 55 0.4 // = GLAT 0.000 SCANTYPE SCAN // active scan in equatorial coordinates STARTX 0 // scan start offset in RA - ie track in RA STOPX 0 // scan end offset in RA - ie track in RA STARTY -5 // scan start offset in DEC STOPY +5 // scan end offset in DEC SCANTIME 100 // scan time in seconds OUTFILE jjdecscan
This makes use of the proposed projection type called "ZEN" which is a "native zenithal projection". This would simply point the pole of the native system at the "special point" and would therefore aleviate the need for the DEC-90 calculation. The euler angles would be set to:
The input file would become:
Note: This needs a preceding SETUP section to give all mandatory keywords for this single scan.
OBJECT TAU A circular scan COORDSYS EQUATORIAL EQUINOX B1950 SCANTYPE SCAN RA 82.880 // point pole of native system at source DEC 21.982 PROJTYPE ZEN // zenithal coordinates with no projection STARTX 0 // do full circle STOPX 360 // do full circle STARTY HP // spec for circle at halfpower point STOPY HP // HP got from SYPARM for this frequency OUTFILE taucirc
MG: even more user-friendly is to let the software do the obvious stuff:
OBJECT TAU A circular scan COORDSYS EQUATORIAL EQUINOX B1950 SCANTYPE SCANCIRC RA 82.880 // point pole of native system at source DEC 21.982 RADIUS HP // spec for circle at halfpower point OUTFILE taucirc
This map is to be observed on 1999 11 11. It uses the default scanrate and binsize.
JJ: Added projection stuff. Uses the JPL solar system ephemeris.
Note: I haven't checked that this conforms with our current input format and mandatory requirements - it lacks STRTDATE, ENDDATE etc.
OBJECT SUN // Sun map PROJECT Sun map at 2.5cm PROPOSAL 1999.004 OBJECT SUN // use JPL solar ephemeris for position OBSERVER J. QUICK COORDSYS ECLIPTIC // sun position specified by ecliptic long. PROJTYPE TAN // ###JJ### make a map that can be directly // compared with an optical image. RESTFREQ 12180E6 // 2.5cm INSTRUME TP // use total power radiometer pair SCANTYPE MAP // small map, uninterrupted OUTFILE sunmap SIZELONG 1.0 // 1 x 1 degree map
This map is to be observed on 1999 11 03. It uses the default scanrate and binsize.
Note: I haven't checked that this conforms with our current input format and mandatory requirements - it lacks STRTDATE, ENDDATE etc.
OBJECT MOON // Moon map PROJECT Moon map at 2.5cm PROPOSAL 1999.005 OBJECT MOON // use JPL moon ephemeris OBSERVER J. QUICK COORDSYS EQUATORIAL // moon position using apparent equatorial EQUINOX APPARENT // ###JJ### explicit specification needed PROJTYPE TAN // ###JJ### make a map that can be directly // compared with an optical image. RESTFREQ 12180E6 // 2.5cm INSTRUME TP // use total power radiometer pair SCANTYPE MAP // small map, uninterrupted OUTFILE moonmap SIZELONG 1.0 // 1 x 1 degree map
This is an extract from a typical 6.7-GHz methanol monitoring input file, set up as though the old correlator were running on the NCCS. Some keywords may change for the new correlator, and additional ones may be needed.
SETUP OBSERVER S. GOEDHART PROJECT 6.7-GHz methanol maser monitoring PROPOSAL 1999.006 CONF 6668SPEC RESTFREQ 6668.518E6 // methanol SCANTYPE SPECTRUM // implies instrument = spectrometer ENDCONF DEFCONF 6668SPEC ENDSETUP // blank line for readability OBJECT G213.71-12.60 PNT // name change for pointing SOURCE 1 COORDSYS GALACTIC // ###JJ### not strictly needed because of GLON 213.710 // GLAT -12.600 // SPVLSR +11.0 // km/s SPBW 1.0e6 // Hz SPFS 0.5e6 // Hz (freq switch by half the bandwidth) SPCHAN 1024 // Numbe rof correlator channels SPTIME 300 // each scan 5 minutes long SPPOINT // do pointing observations N S E W ON ON OUTFILE sgg21371 OBJECT G213.71-12.60 // standard name for source SOURCE 2 COORDSYS GALACTIC // ###JJ### not strictly needed because of GLON 213.710 // GLAT -12.600 // SPVLSR +11.0 // km/s SPBW 1.0e6 // Hz SPFS 0.5e6 // Hz (freq switch by half the bandwidth) SPCHAN 1024 // Numbe rof correlator channels SPTIME 300 // each scan 5 minutes duration REPEATS 4 // do 4 ON ON scan pairs OUTFILE sgg21371 and so on for the next object.
Pulsar timing requires many parameters to be defined. The example below is
derived from the information in the file PULSAR::16 on the HP1000, and the
Pulsar Observing Software User's Guide
.
Pulsar timing input file for regular monitoring of the Vela pulsar at two frequencies:
Setup observer S.Buchner project Dual frequency continuous monitoring of Vela Pulsar Proposal 2003.001 scantype PULSAR strtdate 2003 05 16 strttime 00 00 00 enddate 2003 07 30 endtime 12 00 00 priority Interrupt CATALOG ../pulsars/pulscat.txt CONF 18cm RESTFREQ 1668.0E6 // observe at 18cm, standard frequency BANDWDTH 8.0E6 ENDCONF CONF 13cm RESTFREQ 2272.8E6 // also observe at 13cm, std. freq. BANDWDTH 16.0E6 ENDCONF endsetup Object PSR 0833-45 USECONF 18cm pltconst 150 plpint 500 plcal HALIST -6.0h -5.0h -4.0h -3.0h -2.0h -1.0h 0.0h 1.0h 2.0h 3.0h 4.0h 5.0h 6.0h OUTFILE 0833_18cm repeat 1 endobj Object PSR 0833-45 USECONF 13cm pltconst 150 plpint 500 plcal HALIST -6.0h -5.0h -4.0h -3.0h -2.0h -1.0h 0.0h 1.0h 2.0h 3.0h 4.0h 5.0h 6.0h OUTFILE 0833_13cm repeat 1 endobj Object PSR 0833-45 USECONF 18cm pltconst 150 plpint 500 OUTFILE 0833_18cm endobj Object PSR 0833-45 USECONF 13cm pltconst 150 plpint 500 OUTFILE 0833_13cm endobj
The pulsar catalogue, pulscat.txt
, would have multiple entries like
this:
Object PSR 0833-45, Vela pulsar coordsys equatorial ra 8h 35m 20.6761s dec -45d 10m 35.7581s equinox J2000 plperiod 0.089339249061 plpdrv1 124.4499E-15 plpdrv2 -44.390E-25 pldm 68.02 pldmdrv 0.0 plepoch 52567.56263
Holography requires a few basic parameters, this is an example of an input file to create a map using the satellite Eutelsat W2
SETUP OBSERVER Benjamin Klein PROJECT Test of Holography PROPOSAL 2003.01 OBSLOCAL ben STRTDATE 2007 349 STRTTIME 00 00 00.0 ENDDATE 2008 350 ENDTIME 00 00 00.0 PRIORITY interrupt ENDSETUP OBJECT EUTELSAT W2 SOURCE 1 RESTFREQ 11698.0E6 BANDWDTH 4E6 SCANTYPE Holography comment coordsys apparent source = 1 HORSSZ 100 HORSPC 0.045 HOSPNT 1 HOCHN 1024 HOITM 3 // HOEPNT - automatically set to 100 HONMBST 5 HOSCPBST 4 //HOOVRSMP - automatically set 1.2 EPHEM1 1 25491U 98056A 08044.78960597 .00000105 00000-0 10000-3 0 4744 EPHEM2 2 25491 0.0575 346.1859 0004405 332.7245 124.4927 1.00272189 34315 LONOFFSE 0.02907 // HA actual - trying LATOFFSE 0.00296 //DEC ENDOBJ