Relation between coordinates parameters of the 30m telescope
SL, 06/2013.
'''Important preliminary remark''': this page is for the moment a kind of sand box where I gather various informations that may be useful for the implementation of a new instrument, and that I gathered from various documents, Wiki pages, and email exchanges with specialists of the 30m telescope. Ideally I would like that this page gathers the informations concerning the various coordinates values delivered by the telescope, the relations between them, and that it also centralizes links to related documents/wiki pages. Of course all this would have to be verified and approved by the 30m specialists (which is not the case for now).
== Table of the coordinates parameters generated by the New Control System of the telescope, in particular the antMD.trace category, that are also broadcast on the local network by the Elvin server, the correspondence with the parameters in the IMBFITS files recorded at the end of each scan, and the time stamp information and possibly units of these parameters.
antMD.trace. parameter name |
IMBFITS parameter name |
units |
Description |
time stamp of the value |
|
SITELONG |
rad or deg ? |
Telescope longitude |
static |
|
SITELAT |
rad or deg ? |
Telescope latitude |
static |
|
CTYPE1 |
string |
Source coordinate system for BASELONG (e.g. AZ, RA, etc.) |
static |
|
CTYPE2 |
string |
Source coordinate system for BASELAT (e.g. EL, DEC, etc.) |
static |
|
RXHORI |
rad ? |
Nasmyth offset in Pointing Model |
static |
|
RXVERT |
rad ? |
Nasmyth offset in Pointing Model |
static |
|
RXHORICO |
rad ? |
Nasmyth offset in user defined (Pako) |
static |
|
RXVERTCO |
rad ? |
Nasmyth offset in user defined (Pako) |
static |
|
P1 .. P6 |
rad ? |
Pointing Model parameters |
static |
|
SYSTEMOF |
string |
System in which LONGOFF/LATOFF are reported |
static |
LST |
LST |
seconds ? |
Local Sideral Time |
predicted value at TimeStamp + 2s |
MJD |
MJD |
days |
Modified Julian Day |
predicted value at TimeStamp + 2s |
basisLat |
BASELONG |
|
|
|
basisLong |
BASELAT |
|
|
|
xOffset |
LONFOFF |
|
|
|
yOffset |
LATOFF |
|
|
|
actualAz |
CAZIMUTH |
|
|
|
actualEl |
CELEVATION |
|
|
|
trackAz |
AZIMUTH |
|
|
|
trackEl |
ELEVATION |
|
|
|
TRACKING_AZ |
|
|
|
|
TRACKING_EL |
|
|
|
|| MaxTrAz -9.324561 degrees ? tracking error @ TimeStamp-1s/slowRate || MaxTrEl -1293306.035088 degrees ? tracking error @ TimeStamp-1s/slowRate || MinTrAz -10.482456 degrees ? tracking error @ TimeStamp-1s/slowRate || MinTrEl -1293306.394737 degrees ? tracking error @ TimeStamp-1s/slowRate
antMD.trace.SigTrAz 9.880497 degrees ? RMS tracking error @ TimeStamp-1s/slowRate antMD.trace.SigTrEl 1293306.255894 degrees ? RMS tracking error @ TimeStamp-1s/slowRate antMD.trace.actualAz 330.423504 degrees ? encoder Az @ TimeStamp-1s/slowRate antMD.trace.actualEl 359.239449 degrees ? encoder Az @ TimeStamp-1s/slowRate antMD.trace.basisLat 1.079896 radians ? real DEC @ TimeStamp+2s antMD.trace.basisLong 0.635520 radians ? real RA @ TimeStamp+2s antMD.trace.fastRate 128 number of interpolations between 2 slowRate antMD.trace.inSegment -1 ? antMD.trace.slowRate 1 frequency in Hz at which all these data are generated antMD.trace.timeStamp 2009-11-30T08:08:46.001 time at which the antMD message is sent antMD.trace.trackAz -11658.175439 micro radians ? real Az of telescope on sky ? @ TimeStamp-1s/slowRate antMD.trace.trackEl -1096643.438596 micro radians ? real Az of telescope on sky ? @ TimeStamp-1s/slowRate antMD.trace.value ? antMD.trace.xOffset 0.000000 micro radians ? offset from source in sky in Az or RA (depend system chosen in PaKo) @ TimeStamp+2s antMD.trace.yOffset 0.000000 micro radians ? offset from source in sky in El or Dec (depend system chosen in PaKo) @ TimeStamp+2s