Talk given by Andy Bunker on behalf of
Talk given by Andy Bunker on behalf of Ian Parry, Euro 3 D meeting 02 July 2002 Ian Parry, Andrew Dean, Dave King, Andy Bunker, Steve Medlen, Jim Pritchard, Rachel Johnson, Anamparabu Ramaprakash, Rob Sharp, Richard Mc. Mahon, Craig Mackay, Gerry Gilmore, Douglas Gough, 3 D meeting Tenerife July 2002
GEMINI-SOUTH 3 D meeting Tenerife July 2002
GEMINI-SOUTH CIRPASS will go here 3 D meeting Tenerife July 2002
Integral Field Spectroscopy · 490 spatial samples and several image scale options (fibre-fed) · Operation in the range 0. 85 -1. 8 mm · Limiting magnitudes of J~21. 9 and H~20. 9 in 3 hours on Gemini · Limiting flux ~2 e-18 ergs/sec/cm^2 · Large wavelength coverage (Dl=0. 44 mm) at R~3100 in a single integration with a 2048 array · Spectral resolutions up to R~26, 000 3 D meeting Tenerife July 2002
Current Performance � Using a 1024 x 1024 Hawaii-I array and an 8 -inch telescope � End to end throughput (J & H) ~6 -8% � Intrinsic detector dark current is 0. 03 e/sec/pix � Instrument backgrounds (e/s/pix): 0. 15 (J), 0. 17 (H-short), ~2 (H-long) � Readnoise 17 e rms per read � Sky-sky noise 0 lim flux of 2 e-18 ergs cm-2 sec-1 in 3 hours on an 8 -m telescope � Line FWHM 1. 4 pixels = 3. 1 Angstroms (400 l/mm) 3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
CIRPASS SCIENCE Star formation history 1<z<2 rotation curves of z~1 galaxies Damped Lyman-alpha systems Gravitational lenses QSO environments ULIRGS Alignment effect LINERs Galactic centre Centres of globular clusters Brown Dwarfs Star formation regions Solar system - Kuiper belt, Satellites Cataclysmic variables 3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
CIRPASS - FOREOPTICS SPIRAL concept Changing scale or telescope only involves changing the magnifying lens 3 D meeting Tenerife July 2002
Image Scales Using the CIRPASS IFU on the VLT or Gemini 8 -m Sampling scale (arcsec/lens) FOV (arcsec) 0. 33 0. 25 0. 12 12. 2 x 5. 0 9. 3 x 3. 5 4. 4 x 1. 7 3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
Suppression Masks (1998) 3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
CIRPASS FILTER WHEEL 3 D meeting Tenerife July 2002
Observing sequence �Read array very 1 -5 minutes (CR rejection and readnoise reduction) �Beam switch so that each fibre spends half the time on object and half the time on sky: ABBA sequence �Dither so that each spatial sample on object is measured using at least 8 different areas on the array 3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
Data reduction software �Pipeline controlled by fits headers �Runs in real-time under IRAF �Supports Euro 3 D data format standard (Euro-network starts July 2002) �Sky subtraction, flat-fielding, CR rejection, spectral extraction, 2 d continuum, line and velocity maps, wavelength calibration, flux calibration, etc. 3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
SKY-DARK 3600 s long J 3 D meeting Tenerife July 2002
SKY-DARK 3600 s short H 3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
3 D meeting Tenerife July 2002
CIRPASS Raw Beam-switched (sky-subtracted) 3 D meeting Tenerife July 2002
CIRPASS Sky minus sky, 3 hours, ~500 counts in line gives 2 e-18 ergs/sec/cm^2 flux on 8 m 3 D meeting Tenerife July 2002
H=6. 11, KO V star, 15 mins Cambridge Water 3 D meeting Tenerife July 2002
Further improvements to S/N � Look at a darker sky � Use a bigger telescope � Alternative 1024 array and new 2048 array have higher QE, etc. � Reduce effective read-noise by using more NDRs � A new 1. 8 mm shortpass filter will give an instrument background of ~0. 05 e/s/pix � Use optimally designed suppression masks 3 D meeting Tenerife July 2002
Schedule � CIRPASS was shipped to Gemini-S mid-June � 2 -3 week test programme using our small test telescope at Cerro Pachon � 5 night Science Demonstration run in early Aug on Gemini-S � 8 night MOS run on the AAT in Oct 3 D meeting Tenerife July 2002
Conclusions � CIRPASS worked very well in Cambridge and we are ready to begin a campaign of scientific exploitation on major telescopes � IFU is easily interfaced to various telescope focii including AO feeds - smaller telescopes give wider FOV � IFU is better than a slit for conventional longslit targets � Very sensitive - reaches very faint limits � Very versatile NIR spectrograph - IFU, MOS, 3000<R<26000 3 D meeting Tenerife July 2002
- Slides: 38
