pilot: pathfinder for an international large optical telescope -performance specifications

PILOT:

Pathfinder for an International Large OpticalTelescope

-performance specifications

JACARA Science Meeting

PILOT

Friday March 26

Anglo Australian Observatory

Jon Lawrence

The data

• Turbulence:

– SODAR (winter 2003/4)– MASS (winter 2004)– DIMM (summer 2003/04)

• Sky temperature and opacity

– SUMMIT (winter 2003/4)– MIR FTI (summer 2003/4)

• Met data

– COBBER (winter 2003/4)– ICECAM (summer 2003/4)– AWS (winter 2004)– met balloons (summer 2000-04)

• Turbulence:

– SODAR (winter 2000/1)– DIMM (winter 2000/01)– microthermals (winter 1996)

• Sky temperature and opacity

– SUMMIT (winter 2003/4)– MIR FTI (summer 2002/3)– MISM (winter 1998)– NISM (winter 2000)

• Met data

– AWS– met balloons

DOME C South Pole

Seeing Data Dome C - 2002/3

DIMM summer 2002: median seeing 1.2 arcsec (Aristidi et al, 2003)

SODAR summer/ winter 2003:median seeing ~0.08 arcsec (33 % floor 0.05)

Seeing Data Dome C - 2003/4

DIMM summer 2003/4:

• data not yet reduced

• median seeing < 1.1 arcsec (~0.4-0.7 arcsec)

• isoplanatic angle ~ 10 arcsec

10 100 1000 100001E-20

1E-19

1E-18

1E-17

1E-16

1E-15

1E-14

1E-13

CN2

(m-2/3

)

Height above ground level (m)

CN2 profile Dome C Bad

r0 = 0.05 m (1.8 arcsec seeing)


iso = 9.5 arcsec fG = 30 Hz


10 100 1000 100001E-20

1E-19

1E-18

1E-17

1E-16

1E-15

1E-14

1E-13

CN2

(m-2/3

)


CN2 profile Dome C Good





iso = 30 arcsec fG = 2Hz


10 100 1000 100001E-20

1E-19

1E-18

1E-17

1E-16

1E-15

1E-14

1E-13

CN2

(m-2/3

)


CN2 profile Mauna Kea

iso = 2 arcsec fG = 50 Hz




iso = 30 arcsec fG = 2Hz




Atmospheric parameters

seeing (arcsec) isoplanatic angle Greenwood (arcsec) Frequency (Hz)

Mauna Kea 0.50 2-3 50

Dome C 0.15 - 0.50 10-30 2-10

10 100 1000 100001E-20

1E-19

1E-18

1E-17

1E-16

1E-15

1E-14

1E-13

CN2

(m-2/3

)


10 100 1000 100000

5

10

15

20

25

30

35

40

Wind speed (m.s

-1

)


Atmospheric parameters

seeing (arcsec) isoplanatic angle Greenwood (arcsec) Frequency (Hz)

Mauna Kea 0.50 2-3 50

Dome C 0.15 - 0.50 10-30 2-10

10 100 1000 100001E-20

1E-19

1E-18

1E-17

1E-16

1E-15

1E-14

1E-13

CN2

(m-2/3

)


10 100 1000 100000

5

10

15

20

25

30

35

40

Wind speed (m.s

-1

)


??

Adaptive Optics

wavefront sensor

wavefront analysis

wavefront control

centroid sensordichroicbeam splitters

to tip-tilt secondary

image camera

telescope optics

guide starobject

tip-tilt control

deformable mirror

PILOT AO systems

• Tip-tilt

– tip-tilt mirror + quad sensor

• Low Order AO

– ds=0.3 (30-50 actuators)

• High Order AO

– ds=0.08 (500-1000 actuators)

PILOT AO system performance

• Low Greenwood frequency:– lower feedback loop frequency– higher integration time– fainter stars

lower SNR/bandwidth errors• Large isoplanatic angle

– larger fields– brighter stars

low anisoplanatic error• Better seeing (lower r0)

– less actuators

lower fitting error

Strehl ratio - V band

6 8 10 12 14 16 180.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Strehl Ratio

Guide star magnitude

On-axis low order

DCG

DCBMK

2 4 6 8 10 120.5

0.6

0.7

0.8

0.9

1.0

Strehl Ratio

Star magnitude

Strehl Ratio

Strehl ratio - K band (tip-tilt correction)

6 8 10 12 14 16 18

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Strehl

Magnitude

0 1000.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Strehl

Guide star separation

DCB DCB

DCGDCG

On-axis Off-axis

0.4 1 10

0.1

1

Strehl Width (arcsec)

Wavelength (μ )m

Diff lim 2m

Uncomp DCB

Uncomp DCG

0.4 1 10

0.1

1


Wavelength (μ )m

Diff lim 2m

DCB off-axis

DCG off-axis

on-axis

Uncomp DCB

Uncomp DCG

0.4 1 10

0.1

1


Wavelength (μ )m

Diff lim 2m

DCB off-axis

DCG off-axis

on-axis

Uncomp MK

Uncomp DCG

Uncomp DCB

Gemini altair

Diff lim 8 m

0.4 1 10

0.1

1

diffraction limit 2m


Wavelength (μ )m

8diffraction limit m- on axis AO

- tip tilt correction

Altair on Gemini

Sky emission

3 4 5 6 7 8 9 10 11 12 1314151E-6

1E-5

1E-4

1E-3

0.01

0.1

1

10

100

1000

10000

Sky Brightness (Jy.arcsec

-2

)

Wavelength (μ )m

MK

Emission = 5% @ 0° C

Sky emission

3 4 5 6 7 8 9 10 11 12 1314151E-6

1E-5

1E-4

1E-3

0.01

0.1

1

10

100

1000

10000


-2

)

Wavelength (μ )m

Emission = 5% @ -63° C

SP

Sky emission

3 4 5 6 7 8 9 10 11 12 1314151E-6

1E-5

1E-4

1E-3

0.01

0.1

1

10

100

1000

10000


-2

)

Wavelength (μ )m

Emission = 5% @ -66° C

DC

3 4 5 6 7 8 9 10 11 12 131415

0.0

0.2

0.4

0.6

0.8

1.0

Transmission

Wavelength (μ )m

Sky Transmission - NIR/MIR

MK

3 4 5 6 7 8 9 10 11 12 131415

0.0

0.2

0.4

0.6

0.8

1.0

Transmission

Wavelength (μ )m

Sky Transmission - NIR/MIR

DC

Relative integration time : MK versus SP, DC, DA

3 4 5 6 7 8 9 10 11 12 13 141

10

100

1000

Relative integration time

Wavelength (μ )m

Relative integration time : 8m MK versus 2 m DC PILOT

diffraction limit

3 4 5 6 7 8 9 100.1

1

10

100

relative integration time

wafvlength


3 4 5 6 7 8 9 100.1

1

10

100

relative integration time

wavelength

Seeing limit - extended object


Seeing limit - extended object

v R I

J H

L

M

N

Q1 10

8

10

12

14

16

18

20

22

24

26

Limiting Magnitude

Wavelength (μ )m

extended object

K

vR

IJ

HK

L

M

N

Q

1 105

10

15

20

25

30

Limiting Magnitude

Wavelength (μ )m

-point source

Possible PILOT Instruments

Visible (AO-on) imaging:

4k array (0.03 arcsec/pixel) = 2.3 arcmin FOV

NIR wide field imaging JHK bands:

4k array (0.6 arcsec/pixel) = 10 arcmin FOV

DF imaging KLM bands:

1k array (0.23 arcsec/pixel) = 4 arcmin FOV

MIR imaging N band:

0.5k array (0.7 arcsec/pixel) = 6 arcmin FOV

V band imaging - AO on

10 100 1000

23

24

25

26

27

pilot

DC8

hstvst

jwst ??

keck

MK2m

gemini

Limiting Magnitude

FOV

0.01 0.1 1

28

29

30

31

pilot

DC8

hst

jwst ??

keck

MK2m

gemini

limiting magnitude

Resolution

10 100 1000 1000022

23

24

25

pilot

DC8

hst

vst

jwst ??

keck

MK2m

gemini

Limiting Magnitude

FOV0.01 0.1 1

22

23

24

25

pilot

DC8

hst

vst

jwst ??

keck

MK2m

gemini

limiting magnitude

Resolution

Point source

ext object

100 1000 1000019

20

21

22

23

24

pilot hst

MK2m

vista

jwstkeck

pilot2

geminiMCAO

dc8

limiting magnitudfe

FOV

K band

0.1 119

20

21

22

23

24

pilothst

MK2m

jwstkeck

pilot2

geminiMCAO

dc8

Limiting mag

Resoution

K band

100 1000 1000017

18

19

20

21

22

pilothst

MK2m

vista

jwst

keckpilot2

geminiMCAO

dc8

limiting magnitudfe

FOV

K band

K band imaging - tip tilt

0.1 117

18

19

20

21

22

pilothst

MK2m

vista

jwst

keckpilot2

geminiMCAO

dc8

Limiting mag

Resoution

K band

Point source

ext object

10 100 10006

8

10

12

14

16

pilotMK2

jwst

keckgemini

DC8

Limiting MAgntiude

FOV1 2

6

8

10

12

14

16

pilotMK2

jwst

keckgemini

DC8

Limiting magnitude

resolution arcsecs

1 26

8

10

12

14

16

pilot

MK2

jwst

keckgemini

DC8

Limiting magnitude

resolution arcsecs

10 100 10006

8

10

12

14

16

pilot

MK2

jwst

keck gemini

DC8

Limiting MAgntiude

FOV

N band imaging

Point source

ext object

Summary

• Visible AO system (40-100 actuators plus tip-tilt):

– near diff lim for on-axis stars 8-12 mag– off-axis reasonable performance up to 1-2 arcmin– highest ground based resolution!!– mirror figure error is very important < 50 nm rms required– spectroscopy?

• Near Infrared K band imaging:

– tip-tilt correction is enough for near diff lim (0.2-0.3 arcsec)– equivalent to 8m ML telescope for extended object, 5m for point source– wide field or narrow field science?

• Mid-Infrared imaging:

– niche is wide field sensitivity

pilot: pathfinder for an international large optical telescope -performance specifications

Documents

arcsec fg

arcsec isoplanatic angle

dimm winter

arcsec aristidi et

sodar summer winter

sodar winter

opacitysummit winter

nism winter