MAIA The 3-channel Mercator Advanced Imager for Asteroseismology. Steven Bloemen International Francqui Symposium 4 December 2013

Transcription

1 + MAIA The 3-channel Mercator Advanced Imager for Asteroseismology Steven Bloemen International Francqui Symposium 4 December 2013

2 + Main science driver for MAIA Photometric mode identification of stellar oscillations in subdwarf B stars Example: p-modes in an sdb

3 + What do we need? n Observations in multiple colours, including a very blue band n Preferably simultaneously n Large field of view to have comparison stars in blue band n Fast cadence

4 + Frame-transfer CCDs on loan from ESA (Eddington Mission)

5 + MAIA n 3-channel camera for the 1.2-m Mercator telescope n Large field of view: 9 by 14 armins, 0.28 arcsec/pixel n 3k by 2k + frame transfer CCDs (Eddington Space Mission prototypes) n Ideally suited for sdb asteroseismology and mode identification

6 + Simultaneous observations in 3 colours

7 + Mechanical design D CC ER LL RO T N CO G FILTER INSERT COLLIMATOR U FILTER INSERT R CAMERA G CAMERA R FILTER INSERT PC G CRYOSTAT R CRYOSTAT U DICHROIC GUIDING CAMERA G DICHROIC R DICHROIC CENTRAL BOX U CAMERA CONTROL ELECTRONICS BOX HMI PANEL U CRYOSTAT GUIDING CAMERA

8 + MAIA on its way to La Palma

9 + MAIA on its way to La Palma

10 + MAIA s teething troubles

11 + MAIA s teething troubles

12 + Mercator Inaugurated on 5 September 2013!

13 + Mercator Inaugurated on 5 September 2013!

14 + r, g and u bands

15 + Efficiency ree-channel imager for asteroseismology Table 3. MAIA measured and calculated peak e ciency (instrument and detectors without telescope), zero points (including telescope) and typical atmospheric extinction magnitudes at the Mercator telescope. Band E ciency (%) Zeropoint Atm. extinction meas. calc. (mag) (mag) u g r channel r with stat. nced t on expected to be at least as good. However, the first MAIA observing runs su ered from poor observing conditions and bad seeing. Moreover, the overall image quality was further degraded due to non-perfect alignment of the telescope optics. As a result, image quality and spatial resolution have been severely limited up to now and hence, we could only prove that MAIA on the Mercator telescope is at least capable of producing 0.9- arcsec (FWHM) images in all three channels. The telescope misalignment is currently being corrected. Under more favourable atmospheric conditions, we expect to show substantially better imaging performance. mcat mobs channel g channel u Airmass

16 + Uninterrupted, fast cadence Multiple windows à full width, same height, same on 3 channels Binning Frame transfer (exposure T > readout T) ~35s readout time for full frame Different exposure times (e.g. 10s in r, 10s in g, 20s in u)

17 + Example of MAIA observations (temporary on-site reduction)

18 + Example of MAIA observations Light curve of sdb pulsator Balloon mag Time (seconds)

19 + Example of MAIA observations 5% Reflection effect in a sdb+m-dwarf binary Relative flux 16th mag in R 120s in r and g, 240s in u 7h continuous observations Geier et al., submitted to A&A Time [HJD ] Fig. 6. Multiband light curve of HS taken with the MAIA camera (R, G, U-bands from top to bottom).

20 + Example of MAIA observations KY Uma, sdb p-mode pulsator (e.g. Charpinet+ 2005) 4 modes with amplitude > 0.1 mmag Analysis ongoing e.g. 30s in u-band

21 + Evolution of p-mode amplitude ratios Johnson U, B, V, R, I

22 + Evolution of g-mode amplitude ratios Johnson U, B, V, R, I

23 + Other ongoing projects n Asteroseismology of sdbs n Flickering in CVs, YSOs (Scaringi) n Asteroseismology of massive stars in clusters (Saesen) A&A 559, A26 (2013) DOI: / / c ESO 2013 Astronomy & Astrophysics MAIA, a three-channel imager for asteroseismology: instrument design? Gert Raskin 1, Steven Bloemen 1,4, Johan Morren 1, Jesus Perez Padilla 1,2, Saskia Prins 1,2, Wim Pessemier 1, Jeroen Vandersteen 3, Florian Merges 1,2, Roy Østensen 1, Hans Van Winckel 1, and Conny Aerts 1,4

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25 + What happened, really?

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28 Francqui Prize Ceremony 13 June 2012

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