Campuses:
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| * Attitude control requirements (Jacques) | * Attitude control requirements (Jacques) | ||
| * sampling requirement | * sampling requirement | ||
| - | * For CORE, 1/4th, constrained by scan strategy | + | * For CORE, 1/4th, constrained by scan strategy |
| * for each position on the sky, we want to compare compare data, important for systematics | * for each position on the sky, we want to compare compare data, important for systematics | ||
| * The requirement of sampling will translate to the requirement of altitude | * The requirement of sampling will translate to the requirement of altitude | ||
| * Uncertainty on the position of spin axis, from one scan to other, translated to difference between two scans. | * Uncertainty on the position of spin axis, from one scan to other, translated to difference between two scans. | ||
| * good control helps reduce gaps as much as we can | * good control helps reduce gaps as much as we can | ||
| - | + | * | |
| - | * Cross-scan sampling per precession | + | * Cross-scan sampling per precession |
| - | * Currently, T_prec = 10 hours, T_spin = 1 min, which lead to theta = 3' | + | * Currently, T_prec = 10 hours, T_spin = 1 min, which lead to theta = 3' |
| - | * 3' is good for 100 GHz, but not above; we can change T_spin or T_precession | + | * 3' is good for 100 GHz, but not above; we can change T_spin or T_precession |
| - | * Kris does not think changing T_precession / T_ spin can solve the problem globally. Very long precession, penalty is pile up enormously at poles. | + | * Kris does not think changing T_precession / T_ spin can solve the problem globally. Very long precession, penalty is pile up enormously at poles. |
| - | * we are assuming engineering achieving nominal, by 1 arcmin in 3 sigma error per spin. | + | * we are assuming engineering achieving nominal, by 1 arcmin in 3 sigma error per spin. |
| + | * Point reconstruction | ||
| + | * alignment of instrument FOV with reference of spacecraft. change should not be faster than calibration | ||
| + | * Jacques: we need to do simulation to get final number for point reconstruction | ||
| + | * Shaul: 1’’ will be driven by systematics. We will see if 1’’ is reasonable given r value. | ||
| + | * Amy: too loose, worse systematics; | ||