...
| Keyword | (MWA) Valid Values | Change from v1 format? | Notes |
|---|---|---|---|
XTENSION | IMAGE | Image Extension created by MWA DataCapture | |
BITPIX | -32 | Changed: v1 Pre Oct 2014 = -32 (32 bit float) v1 Post Oct 2014= 32 (32 bit integer) v2 = -32 (32 bit float) | number of bits per data pixel (negative is floating point) |
NAXIS | 2 | number of array dimensions | |
NAXIS1 | (coarse channel width / fine_chan_width) * pols(xx,xy,yx,yy) * 2 For 10 kHz fine chan: (1280 / 10) * (4) * 2 == 1024 | Changed: was: baselines * pols * 2 | Fine Channels * Polarisations * 2 (real/imag) |
NAXIS2 | For 128T = (128*129)/2 = 8256 For 256T = (256*257)/2 = 32896 | Changed: was: fine channels | Baselines |
PCOUNT | 0 | number of group parameters | |
GCOUNT | 0 | number of groups | |
COMMENT | FITS (Flexible Image Transport System) format is defined in 'Astronomy | ||
COMMENT | and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H | ||
TIME | e.g. 1531077040 | Unix start time of this HDU | |
MILLITIM | 0-999 | Milliseconds component of TIME | |
MARKER | e.g. 0,1,2... n (where n is the final time step) | Data offset marker of HDU (all channels should match). The marker increments by 1 per time step | |
| U2S_VER | X.Y.Z | Version of the mwax_u2s program that captured the UDP packets for this observation | |
| CBF_VER | X.Y.Z | Version of the mwax_db2correlate2db program that performed the F and X stage correlation for this observation | |
| DB2F_VER | X.Y.Z | Version of the mwax_u2s db2fits program that wrote this fits file. |
...