Open Access

Table 1.

AO numerical simulation parameters.

Numerical simulation configuration
D = 39 m diameter
Telescope ELT pupil
 798 aggregated hexagons
 No support spiders

von Kármán, ground layer only
r0 at 500 nm: variable in a
Turbulence layer  useful range of 7.0–35.0 cm
L0 = 25 m
m s−1

 Subapertures 92 × 92 – pixel size 42 cm.
24 080 useful pixels
 Wavelength Monochromatic, 658 nm
 Throughput 0.28 (including quantum efficiency)
 Modulation Circular, 4 radius
 Readout noise 0.3 e

Source On-axis natural guide star
Guide star flux Zero point: 2.6 × 1010 ph s−1 m−2

Tip-tilt mirror
Hexagonal M4 model pattern
Adaptive mirrors Pitch of 54 cm
Coupling of 0.24
4310 controlled actuators
Both with infinite bandwidth

RTC controller
 Loop rate 500 Hz
 Method Linear modal integrator
 Latency Data flow 1 frame + MVM 1 frame
 Basis DM Karhunen–Loève basis (a)


Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.