Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.eso.org/~rsiebenm/FTP/PPT/ELTera.pdf Дата изменения: Wed Oct 10 12:15:41 2007 Дата индексирования: Fri Feb 28 11:33:02 2014 Кодировка: Поисковые слова: hawaii

The experience from VISIR and the design of an ELT mid-infrared instrument

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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VLT Imager and Spectrometer for the InfraRed
Commissionned in 2004 on Melipal
Diffraction-limited (seeing < 0.8'')

Multi-mode instrument :
Imaging: N(8-13 m) and Q(16-24 m) 18 filters (R=20 to 100) pfov: 0.075'' and 0.127''

Spectroscopy: LR (R=300), MR (3000) and HR (15000-30000 in Q or N)
E.Pantin & R.Siebenmorgen Science with the VLT in the ELT era

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VISIR in context

Spatial resolution and sensitivity:
Spitzer: VISIR: MIDI: ~10Jy ~1mJy ~Jy (Jaffe)
NGC 1068 Poncelet et al. 07

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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SSCs in active galaxies
Ne II 12.8 µm

1"
M6 M4

Cluster parameters:
Age Mass
E.Pantin & R.Siebenmorgen

~ 7 Myr ~ 106 M

NGC1365

Galliano et al.

Luminosity ~ 5x109 L

Unresolved by Spitzer
Science with the VLT in the ELT era

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High-resolution spectroscopy
N7582 NeII

Wold et al. 2006

Circumnuclear velocity:

13km/s resolved

Central black hole mass: < 5.5 x 109M
E.Pantin & R.Siebenmorgen Science with the VLT in the ELT era

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Protoplanetary disk at 0.3''

Martin-Zaidi et al., 07

Warm
HD97048 Lagage et al., 06

H2 gas: ~ 0.01 ­ 1 MJ
within 35AU

Isophotes -> flaring disk geometry
E.Pantin & R.Siebenmorgen

Disk age ~3Myr
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Science with the VLT in the ELT era


Low-mass companions

VISIR viz. Spitzer: Characterization of spectral types
E.Pantin & R.Siebenmorgen

Sterzik & Pantin, 08

Science with the VLT in the ELT era

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VISIR detector: reads + cooling

1Hz feature from ccc

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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Present VISIR detectors

Cosmetics:
- bad pixels - striping

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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Large scale gradient ?

+0.01 %

-1.80 %

+2.24 %

-0.44 %

- Flat fielding or - Nodding parameters: AO replay ?, ...
E.Pantin & R.Siebenmorgen Science with the VLT in the ELT era

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Chopping: background subtraction

0.25Hz

Chopp. frequency < 1 Hz
E.Pantin & R.Siebenmorgen

->

increase of noise
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Science with the VLT in the ELT era


VISIR: Low res spectroscopy
Standard star

Need: N-band in 1 exposure
E.Pantin & R.Siebenmorgen Science with the VLT in the ELT era

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Future detectors:
Acquarius

BLIP performance Larger format 1k x 1k Pixel gain stability ~10-5: flat-fielding ability nodding only ?
MIDI assembly design

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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Direct MIR imaging of sEarths at the ELT

1L , 1r

J

sensitivity limit in 1h

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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MIR imaging of sEarths

1L , 1r

J

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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MIR spectra of BD/Gplanets

Resolution (D=10pc) JWST 35AU MIDI 5AU
BD models Burrows et al. 97

E.Pantin & R.Siebenmorgen

Science with the VLT in the ELT era

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Lessons learned
Detectors Seeing limited Nodding stability -> gain stability/FF -> AO needed in MIR -> active optics replay

ELT contrast challenge -> coronograph, phase mask

>> Instrument design <<
Multi mode viz. i) Imager (+ low res)
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ii) "sCRIRES'' (high res)
E.Pantin & R.Siebenmorgen Science with the VLT in the ELT era