Download presentation
Presentation is loading. Please wait.
Published byCamron Ward Modified over 8 years ago
1
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Smart Focal Plane Spectropolarimetry with the E-ELT Klaus G. Strassmeier, Leibniz-Institute for Astrophysics Potsdam (AIP), Germany With E-ELT science cases supported by:
2
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Science cases: a community proposal for the E-ELT http://www.eso.org/sci/facilities/eelt/science/doc/
3
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Exoplanet transitspectroscopy in integrated light Extraction of Stokes-I differential transit profile (FeI641.1) („planet-with-atmosphere minus planet-without-atmosphere“): G2V star vsini=15 km/s, Super-Earth R=2.5 R E, R atmos =750km PTV≈10 -6
4
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Exoplanet transitspectroscopy in polarized light PTV≈10 -4 Model= Boo 10/15/15G without with transit Simulation
5
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Observations Covariance Eigenvectors PCA Wavelet Wavelet Filtering Matrix Cross-Correlation Transform & Reconstruction Test input Reconstruction Signal extraction and inversion
6
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 A few trivial-looking situations for the E-ELT Is the user demand high enough? Imaging vs. spectroscopy? Can one afford to ignore AO in 2020+? Which instrument to feed? if SP… at which spectral resolution R ? Be prepared for only few hours of telescope time and a quick, stand-by, ops mode Is the reconfiguration time for M1 short enough?
7
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 From science wishes to reality On-axis spectropolarimetry with 320- 1600nm coverage simultaneously. Continuum and line polarization; full Stokes vector. Highest possible precision/accuracy. Highest feasible R.
8
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Prototype: PEPSI-Pol at straight-Gregorian foci of the LBT 2 8.4m Stokes IQUV R=120,000 380-910 nm ops in 2013
9
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Strawman design of the SP Acquisition unit (including calibration-light injection) Focal plane Electronics Polarimeter/Collimator Fiber pick up 320-1600nm free range Full Stokes vector
10
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 (4) Fibers to (2) spectrograph Foster Collimator ADCs Cameras Dichroids SFPP – Smart Focal Plane Polarimeter for the E-ELT
11
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Retarder +Foster Collimator ADCs Cameras Dichroids SFPP – Smart Focal Plane Polarimeter for the E-ELT CODEX SIMPLE EPICS METIS New spectrograph X-Shooter like Calibration Science UV arm Opt-NIR arm Diaphragm Fibers
12
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Zoom
13
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Retarder +Foster Collimator ADCs Cameras Dichroids SFPP – Smart Focal Plane Polarimeter for the E-ELT CODEX SIMPLE EPICS METIS New spectrograph X-Shooter like Calibration Science UV arm Opt-NIR arm Diaphragm Fibers
14
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 The 39m E-ELT M1 irregularly shaped 39.3m outer diameter 37m entrance pupil M2 4090mm allows „free focus position“ M3 circ. 3756mm M4 = adaptive mirror M4 ellip. 2380mm M5 = tip-tilt mirror M5 ellip. 2600mm IF Intermediate Focus M2 M5 M4 M3M1 IF
15
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Natural- vs. Laser-Guide-Star focus NGS LGS
16
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 The (symmetric) intermediate f/4.4 focus Not open for science Image quality poor Within M4 hole Need to move ADC FOV Ø 1 arcmin Beam Ø 481mm Wavefront sensing for M1 in 5-10 arcmin ring in Nasmyth → severe vignetting issues in IF
17
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Space constraints EELT intermediate f/4.4 focus M4 = off limit due to d>30cm constraint; = available space.
18
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 SFPP in intermediate focus
19
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 … more problems: the parking volume
20
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 … more constraints: the parking-lot volume
21
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011
22
Space constraints EELT intermediate f/4.4 focus
23
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 Who else wants the focus? 1. General purpose (intrafocal) ADC 2. Calibration Unit for the AO system (AOCU) 3. Retarder for EPICS/METIS-Pol calibration AOCU needs light sources in IF → incompatible with anything else. SFPP could include EPICS/METIS-Pol calibration module.
24
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 One scientific conclusion 2022+ many Earth-sized (transiting) planets will be known. Who can detect their magnetospheres? E-ELT + spectropolarimetry could contribute to the scientific search for the most-likely places for life in our galaxy.
25
K. G. Strassmeier, Polarimetry with ELTs, Utrecht, Nov./Dec. 2011 (Technical) Conclusions Provide the full Stokes vector as f( ) at P/P 10 -5 Imaging-Pol at IF is optically not advisable (coma!) IF is suited for seeing-limited, on-axis spectropolarimetry for 320-1600nm. Combine with EPICS-PCU and METIS-PCU into a smart focal plane not easy but likely possible. SP could feed either two spectrographs (380-900nm + 1000-1600nm) via one pair of fibers; or three spectrographs (plus 320-380nm) via a second pair of (uv) fibers. All simultaneously. e.g. an encapsulated fiber-fed, bench-mounted X- Shooter somewhere on the Nasmyth platform.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.