sample:
One sample of ACA image telemetry. This could be a real image readout or it
could be a null 4x4 image when the ACA is not tracking. Be aware that the
sample period is faster for null 4x4 images (1.025 sec) than for typical 6x6
or 8x8 tracked images (2.05 or 4.1 sec respectively).
Kalman samples: Subset of samples when ACA could be tracking stars (AOPCADMD == NPNT & AOACASEQ == KALM)
dr3:
Subset of tracked Kalman samples with radial centroid residual < 3 arcsec.
This corresponds to "high quality" readouts. This effectively includes the
track subset (AOACFCT == TRAK) because readouts with no TRAK are assigned an
infinite centroid residual.
dbox5: Subset of tracked Kalman samples with centroid residual within a 5 arcsec box.
This corresponds to spatial filter used by the OBC for inclusion in Kalman
filter. This effectively includes the track subset (AOACFCT == TRAK) because
readouts with no TRAK are assigned an infinite centroid residual.
track: Subset of Kalman samples where the image is being tracked (AOACFCT == TRAK)
sat_pix: Subset of Kalman samples with saturated pixel flag OK (AOACISP == OK)
ion_rad: Subset of Kalman samples with ionizing radiation flag OK (AOACIIR == OK)
mag_est_ok: Subset of Kalman samples that have a magnitude estimate (track & ion_rad)
n_total: Total number of sample regardless of OBC PCAD status
n: Synonym for n_total
n_kalman: Number of Kalman samples
n_dr3: Number of dr3 samples.
n_dbox5: Number of dbox5 samples.
n_track: Number of track samples.
n_ok_3: Number of (track & sat_pix & ion_rad & dr3) samples
n_ok_5: Number of (track & sat_pix & ion_rad & dbox5) samples
n_mag_est_ok: Number of (track & ion_rad) samples
n_mag_est_ok_3: Number of (track & ion_rad & dr3) samples
n_mag_est_ok_5: Number of (track & ion_rad & dbox5) samples
f_dr3: Fraction of mag-est-ok samples with centroid residual < 3 arcsec((mag_est_ok & n_dr3)/n_mag_est_ok)
f_dbox5: Fraction of mag-est-ok samples with centroid within 5 arcsec box((mag_est_ok & n_dbox5)/n_mag_est_ok)
f_mag_est_ok: n_mag_est_ok_3/n_kalman. This is a measure of the fraction of time during
an observation that a magnitude estimate is available.
f_mag_est_ok_3: n_mag_est_ok_3/n_kalman.
f_mag_est_ok_5: n_mag_est_ok_5/n_kalman.
f_ok: n_ok_5 / n_kalman. Same as f_ok_5
f_ok_3: n_ok_3 / n_kalman. This is a measure of the fraction of time during an
observation that the Kalman filter is getting high-quality star centroids.
f_ok_5:
n_ok_5 / n_kalman. This is a measure of the fraction of time during an
observation that the Kalman filter is getting any star centroid at all. This
includes measurements out to 5 arcsec box halfwidth, so potentially 7 arcsec
radial offset.