Near-IR Integral Field Spectroscopy SINFONI and HARMONI Javier - - PowerPoint PPT Presentation

Near-IR Integral Field Spectroscopy

SINFONI and HARMONI

Javier Piqueras López (University of Oxford)

2nd SELGIFS Advance School on IFS Data Analysis 2016

Overview of the talk

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๏Introduction: IFS in the Near-IR ๏VLT/SINFONI ๏Instrument configurations ๏Data reduction, calibration and

analysis of SINFONI data

๏E-ELT/HARMONI

IFS in the NIR: basic concepts

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๏ Integral field spectrograph = Spectrograph + Integral field unit ๏ IFU: divides the 2D FoV into a continuous array ๏ Lenslet array: input image split up by a microlens array ๏ Fibres: input image formed on a bundle of optical fibers ๏ Fibres + lenslets: array of lenslets in front of the fibre bundle ๏ Image slicer: input image formed on a mirror that re-arrange the

image into a pseudoslit

x y λ

Adapted from Alington-Smith and Content (1998)

Focal plane Spectrograph input Spectrograph output

IFS in the NIR: basic concepts

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IFS in the NIR: basic concepts

5 5 10 15 20 25 30 Slitlet 500 1000 1500 2000 Pixel 500 1000 1500 2000 Pixel Wavelength

Defect Sky lines Slitlets Bad pixels Object Object line

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SINFONI: the NIR IFU at VLT

๏ Near-IR (1.1-2.45) integral

field spectrograph at the Cassegrain focus of VLT- UT4 (Eisenhauer et al. 2003, Bonnet et al 2004)

๏ Seeing-limited and AO-

assisted observations

๏ Four gratings: J, H, K and H

+K

๏ ~4000 individual spectra per

data cube

SINFONI configurations

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๏ Spectrograph modes: ๏ Field of view: ๏ 8”x8”, plate scale of 125x250 mas / spaxel (seeing-

limited)

๏ 3”x3”, plate scale of 50x100 mas / spaxel (seeing-

limited, AO)

๏ 0.8”x0.8”, plate scale of 12.5x25 mas / spaxel (AO) ๏ Wavelength bands: ๏ J [1.10 – 1.40] μm, R~2000, FWHM ~ 4pix ๏ H [1.45—1.85] μm, R~3000, FWHM ~ 3pix ๏ K [1.95—2.45] μm, R~4000, FWHM ~ 2pix ๏ H+K [1.45—2.45] μm, R~1500, FWHM ~ 2pix

Data reduction and calibration

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Data and reduction workflow

On-source (SCI) Sky (SCI)

Cube reconstruction Wavelength calibration Master flat field

On-source (STD) Sky (STD) Calibration frames (~month) Calibration frames (~static) Calibration frames (~nigth)

Distortion Linearity Master dark

SINFONI calibration dataset

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๏ A complete dataset should contain: ๏ Science frames: on-source frames + sky frames [OBJECT, SKY] ๏ Dark frames: ~3 frames per DIT [DARK] ๏ Linearity frames: ~24 frames [LINEARITY_LAMP] ๏ Distortion frames: ~75 fibre frames + 2 flat fields + 2 lamp frames

[FIBRE_NS; FLAT_NS; WAVE_NS]

๏ Lamp frames: ~2 frames, lamp on and off [WAVE_LAMP] ๏ STD star frames: ~1 on-source + 1 sky (optional) [STD,SKY_STD] ๏ In addition, some static calibration tables are needed (provided with

the pipeline)

2-0 3-1 4-2 5-3 6-4 8-6 9-7 Vibrational transitions

Thermal background and sky emission

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1.4 1.6 1.8 2.0 2.2 2.4 Wavelength [µm] 2 4 6 8 Flux density [x10-11 erg s-1 cm-2 µm-1 arcsec-2] d n a b

• K

d n a b

• H

Thermal background

๏ Two sources: ๏ Thermal background: atmospheric (+ telescope) emission dominates

beyond ~2.3 μm

๏ Airglow emission: OH vibrational lines that dominates below ~2.3 μm

Atmospheric transmission: Efficiency curves

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๏ Atmospheric absorption in the near-IR: vibrational transitions of water vapor ๏ Depends on the airmass, varies with time… ๏ Although it can be modeled, it is usually corrected using standard stars:

efficiency curves

H+K band

1.4 1.6 1.8 2.0 2.2 2.4 Wavelength [µm] 1 2 3 4 Normalised flux

Spectrum

Atmospheric transmission: Efficiency curves

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๏ Atmospheric absorption in the near-IR: vibrational transitions of water vapor ๏ Depends on the airmass, varies with time… ๏ Although it can be modeled, it is usually corrected using standard stars:

efficiency curves

H+K band

1.4 1.6 1.8 2.0 2.2 2.4 Wavelength [µm] 1 2 3 4 Normalised flux

Spectrum BB fit

Atmospheric transmission: Efficiency curves

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๏ Atmospheric absorption in the near-IR: vibrational transitions of water vapor ๏ Depends on the airmass, varies with time… ๏ Although it can be modeled, it is usually corrected using standard stars:

efficiency curves

H+K band

1.4 1.6 1.8 2.0 2.2 2.4 Wavelength [µm] 1 2 3 4 Normalised flux

Spectrum Efficiency BB fit

Instrumental line profiles

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50 100 150

• 0.2

0.0 0.2 0.4 0.6 0.8 1.0 5 10 15

• 0.2

0.0 0.2 0.4 0.6 0.8 1.0 50 100 150

• 0.2

0.0 0.2 0.4 0.6 0.8 1.0 5 10 15

• 0.2

0.0 0.2 0.4 0.6 0.8 1.0

H-band (super-sampled) K-band (super-sampled) H-band K-band

๏

Spectral resolution in SINFONI depends on pre-optics:

๏

Band

๏

Plate scale

๏

Wavelength

๏

Line profile can be characterized using arc/sky lines

๏

H-band, 250 mas, [1.62,1.70] μm ~[FeII] line

๏

K-band, 250 mas, [2.12,2.22] μm ~H2 1-0S(1) and Brγ lines

๏

Kinematic studies: It is essential to characterize the instrumental line profile

Median Gaussian

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European Extremely Large Telescope: E-ELT

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HARMONI General Assembly

10 m 5 m 8.75 m

HARMONI in a nutshell

๏ Optical and near-IR IFS (~ 32000 spectra) ๏ Workhorse instrument: design for a wide range of scientific programs ๏ LTAO, SCAO and seeing-limited observations ๏ Spectral coverage ๏ Wavelength range: 0.47 - 2.45 μm ๏ Spectral resolution: 3000, 7000, 18000 ๏ Spatial setup: ๏ FoV: ~9”x6”, 4”x3”, 2”x1.5”, 0.8”x0.6” ๏ Pixel scales: ~30 mas, 20 mas, 10 mas, 4 mas ๏ Sensitivity: up to HAB~27.4 mag (5h, S/N~5, LTAO)

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HARMONI spatial set-up

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60 mas x 30 mas 20 mas 10 mas 4 mas For non-AO & visible observations For optimal sensitivity (faint targets) Best combination sensitivity & spatial resolution Highest spatial resolution (diffraction limited) 6.42” x 9.12” 3.04” x 4.28” 1.52” x 2.14” 0.61” x 0.86” ~214 x 152 (32000) spaxels at all scales

HARMONI simulations of high-z (U)LIRGs

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• 1.0
• 0.5

0.0 0.5 1.0 x [arcmin]

• 1.0
• 0.5

0.0 0.5 1.0 y [arcmin] 2 kpc

• 10
• 5

5 10 x [arcsec]

• 20
• 10

10 20 y [arcsec] 500 pc

HARMONI simulations of high-z (U)LIRGs

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HSIM maps @ z ~2.26 SCAO + 4 mas, Texp ~8h

1 kpc

• 0.3
• 0.2
• 0.1

0.0 0.1 0.2 0.3 x [arcsec]

• 0.4
• 0.2

0.0 0.2 0.4 y [arcsec] 1 kpc

• 0.3
• 0.2
• 0.1

0.0 0.1 0.2 0.3 x [arcsec]

• 0.4
• 0.2

0.0 0.2 0.4

• 100
• 67
• 33

33 67 100

1 kpc

• 0.3
• 0.2
• 0.1

0.0 0.1 0.2 0.3 x [arcsec]

• 0.4
• 0.2

0.0 0.2 0.4

13 27 40 53 67 80

Hα emission v [km/s] σ [km/s]

physical scales of ~70 pc