AOF Wave front sensor modules

GALACSI and GRAALby

Stefan Ströbele

in behalf of the GALACSI and GRAAL Team members:R.Arsenault, R.Conzelmann, B.Delabre, R. Donaldson, M.Duchateau,

G.Hess, P.Jolley, A. Jost, M.Kiekebusch, M.Lelouarn, P.Y.Madec, A.Manescau, J.Pirard, J.Quentin, R.Siebenmorgen, C.Soenke, S.Tordo,

J.Vernet, SPARTA, DSM, 4LGS, ASSIST, Teams,

Integration and IR and CCD detector groups20 Years AO@ESO 1

GRAAL- GALACSI Comparison

20 Years AO@ESO 2

parameter GRAAL GALACSI

Instrument Hawk-I (IR imager) ESO Muse (VIS 3D-spectrograph) Lyon

Mode Maintenance mode GLAO Wide Field Mode Narrow Field Mode

Field of view 10” 7.5’ 1’ 7.5”

AO mode SCAO GLAO GLAO LTAO

Performance (S.R. ~ 80% in K-band) x1.7 EE gain x2 EE gain S.R. >5% (10% goal)

@650nmNatural Guide Stars On axis, ~ 8 mag R-mag 14.5 within

6.7’ to 7.7’ radiusR-mag <17.5 within 52” to 105” radius

On Axis, NIR, Jmag 15Low Order sensing

Sky coverage Close to “bright” stars 95% >90% Science target =

TT reference

4LGSF config. NGS only Ø12’ Ø2’ Ø20”

WFS1 NGS L3-CCD(40*40 sub app.)

4 LGS L3-CCD (40*40 sub app.)1 TT L3-CCD

4 LGS L3-CCD(40*40 sub app.)1 TT L3-CCD

4 LGS L3-CCD(40*40 sub app.)1 IR Low Order

Loop frequency HO loop: ≥ 700 Hz HO loop: ≥ 700 HzTT loop: 250Hz

HO loop: 1 kHzTT loop: 200Hz

HO loop: 1 kHzLO loop: 200-500Hz

AO Types• SCAO:

– 1 Natural guide star, 1 WFS– WFS measures Turbulence– correction by the DM

4

• GLAO: – 4 Laser guide stars, 4 WFSs– 1 Natural guide star, 1 TT Sens.– Average WFS signal High order

DM command + tip tilt meas.• LTAO:

– 4 Laser guide stars, 4 WFSs (closer together)

– 1 Natural guide star, 1 low order sensor

– WFS signal + Tomography Algorithm high order DM command + tip tilt +focus meas.

– correction by the DM

20 Years AO@ESO 5

Altitude [km]

LGS beam Ø

[m]Beam offset [m]

GRAAL GALACSI WFM

GALACSI NFM

LGS at 6’ LGS at 64” LGS at 10”

0 8 0 0 0

1.4 7.86 2.6 0.5 0.07

2.2 7.8 3.9 0.7 0.1

11.2 6.9 - 3.5 0.5

16 6.6 - - 0.8

GRAAL • LGS and NGS pickup

outside the science field• HAWK-I co-rotates to the

sky• Matching of the WFS –

DSM geometries counter rotation of the LGS

WFSs

20 Years AO@ESO 6

• Integration to a existing instrument

Strong constraints to space, weight, access, interfaces

GRAAL big pieces

20 Years AO@ESO 7

Hawk-I shutter

Alu-structur

e

Steel structur

e

bearingTorqu

e drive

Steel flange

LGS trombone

LGS WFS assembly

NGS-TT sensor assembly

MCM assembly

•Bearing (150Nm friction / 80kg)

•Torque drive (500Nm nominal / 70kg)

•Encoder (tape / scanning head)

•Cable-guide system (110 kg)

• Aluminium structure (75 kg)

•Steel structure (50 kg)

Counterweight

GRAAL as seen from (above) the Nasmyth platform

Flange sandwiched between UT-Nasmyth and Hawk-I

Aluminum and steel structure for stiffness and weight constraints

1kHz, 0-noise LGS WFS, optics and trombone focusing on a Ø500 mm (x4)

Retractable focal enlarger x6 (maintenance and commissioning), with WFS pick-up

Internal co-rotator for pupil derotation, direct drive in torque mode, strip band encoder, control loop using VLT-SW standard library

100 kg counterweight to balance 150 kg of electronics

ICPs for quick-separation

GRAAL arrangement on UT4• 2 E-Cabinet on board

– (WFS camera electronics)

• Uses the HAWK-I cable rotator

• Cabinet on the NP – motion control,

• Cabinet on Azimuth PF– SPARTA RTC– 5*NGC backend

• Cabinet in the computer room– SPARTA cluster

20 Years AO@ESO 9

WFS Cabinet 4

HAWK-I

Motion Control Cabinet

SC

P

GRAAL

SC

P

Cable rotatorHawk-I

Na

sm

yth

P

latf

orm

WFS Cabinet 3

RT

C

Azi

mu

th

Pla

tfo

rm

GRAAL Performance

• Image improvement x~2 (EE in 0.1” pixel),Image improvement x~2 (EE in 0.1” pixel),seeing reducer: x0.8 (in Ks)seeing reducer: x0.8 (in Ks)

• Improvement for all seeing conditionsImprovement for all seeing conditions

J. Paufique GRAAL FDR, 10/03/2009

0

10

20

30

40

50

60

70

80

90

100

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60

rela

tiv

e f

req

ue

nc

y (

arb

itra

ry u

nit

s)

theta50 in K-band (")

compared seeing with/without GRAAL

without

with GRAAL

statistics 1999-2004L0 assumed of 25 m, pointing at zenith<= 0.2": results are not representative of the image quality (dif f raction, vibrations, telescope and residual errors become dominant)

0.4 0.7 1.1 1.6 (open loop seeing at 0.5µm)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40

K-band image quality

cum

ula

tive

fre

qu

ency

without

with GRAAL

MUSE-GALACSIMUSE:

– 3d Spectrograph with 300 by 300 spatial resolution elements

– Spectrometer resolution 1500-3000

– 24 spectrographs with 1CCD 4096 by 4096 pixels each

– Wavelength range: 465-930nm – Developed by consortium lead by

CRA-Lyon, PI: R.Bacon

• Nasmyth platform “over” filled (Volume, Weight)

extension for cabinets and access

20 Years AO@ESO 11

GALACSI –FDR 16th June 2009 12

WFM

1’ MUSE FOV

1 faint NGS within 3.4’

FOV

4 Sodium LGSs

Rayleigh cone

NFM

NGS-LGS Configurations

20 Years AO@ESO 13

LGS WFS path

14

14:41:12

New lens from CVMACRO:cvnewlens.seq 10-Apr-08

120.00 MM

Annular Mirror, ( no obstruction for MUSE WFM)LGS dichroic inserted for NFM

WFS, LA

LGS

dic

hroi

c,

Ref

lect

s 58

9nm

tran

smits

th

e re

st t

o T

TS

Pupil relay

Tel

ecen

tric

ity le

ns

Foc

us c

ompe

nsat

orPyramid:•LGS separation near LGS focus•On linear stage to switch between modes

Jitter actuator

2nd Pupil relay

from

VLT

AIT

pup

il

GALACSI Main assembly

• GALACSI at Nasmyth B UT4

• 5 E-Boxes on board

• 1 Cabinet on NP • 1 Cabinet on AZ P• 2 cable chains

AO Facility Review, 24.04.08 15

IRLOS

AO Facility Review, 24.04.08 16

• HAWAI –I 1024 x 1024 pixels, 4 quadrant geometry 4 sub aperture lenslet array

• Frame rate 200/500 Hz for 20by20/8by8 pix RON <15 e-rms

GALACSI Performance

20 Years AO@ESO 17

specification

WFM performance

NFM performance

Outlook to GRAAL

Commissioning

20 Years AO@ESO 18