2. CW5 Berlin 12/2003 COROT planet field observations at INT La Palma H.J. Deeg 1, M. Deleuil 2, C. Moutou 2 1 IAC, Tenerife; 2 LAM Marseille - Observations taken at 2.5m INT, Obsv. Roque Muchachos of the IAC - Wide Field Camera (WFC), with 4 CCDs, 33x33 arcmin total f.o.v. - all fields observed complete in 4 filters: B,V, r’, i’. U filter added for some pointings in latest observations (6-9 June 2003) - reduction performed in collaboration Cambridge - LAM - IAC - aim: creation of photometric catalog that aids to: - select prime target fields (in conjuction with AS, of course...) - select pointing within target field - select stars to be included in observed sample

3. CW5 Berlin 12/2003 2.5m INT, La Palma, 2486m

4. CW5 Berlin 12/2003 Schematics of the pointings COROT AS-target star

5. CW5 Berlin 12/2003 The CCD mosaic of the WFC Overlap of ‘A’ and ‘B’ pointings exposure times: 10-120 sec 'A' and 'B' pointings are taken in all 4 filters

6. CW5 Berlin 12/2003 The reduction pipeline -at Univ of Cambridge, with Wide FieldsSurvey (WFS) pipeline: - identification of stars on images - extraction of photometry in several aperture sizes - generation of average nightly photometric coefficients - production of files with stellar ADU values, one for each colors and pointings -at LAM: - first quality check (evaluation of seeing, selection of basic aperture size) - application of photometric calibration from WFS, - cross-identification of stars in different colors - merging into one file per pointing -at IAC: - final photometric calibration (Feb03 data only) - cross-identification of stars in adjacent or multiple pointings - merging of pointings into single catalog - second quality check (magnitude offsets across pointings) - submission to ExoDat

7. CW5 Berlin 12/2003 mosaicing for a field (HD174866 field shown) dark-red Nobs=1 red Nobs=2 white Nobs ≥3 Number of 4-color observations per star vary from 1 to 4

8. CW5 Berlin 12/2003 The Status of COROT field observations Galactic center: (June 2002, photometric) HD171834 - N6633 field : 19deg 2, 2.16 x 10 6 stars, in exodat HD174866: 8deg 2, 1.48 x 10 6 stars, in exodat Galactic anticenter: (Feb. 2003, seeing/extinction very variable) HD49933:20deg 2,0.48 x 10 6 stars, in exodat HD57006:1.5deg 2, in exodat Galactic center: (June 2003, photometric, currently reduced at Cambridge), included some (time-consuming) U band observations HD171834: 6deg 2 additional (1.5 deg 2 in U) HD177552: 5.5deg 2 (all in U too) HD175726: 7.5deg 2 (with few pointings in U) Galactic anticenter: 9 nights allocated Dec - Jan 03/04 Galactic center: Summer 04, 6 nights conceded

9. CW5 Berlin 12/2003 The HD174866 field is fairly homogenous i < 16 AND V-i < 1.0 For a descripion of spectral classification method, see Moutou et al. i 1.0 i V-i MS Giants

10. CW5 Berlin 12/2003 NGC6633- HD17834 field i < 16, all colors i 1.5 (red) i < 16 AND V-i <1.0 (blue) strong inhomogeneities, clear extinction gradient high extinction, somewhat lower density in total very few background giants, dwarfs are redder

11. CW5 Berlin 12/2003 NGC6633 - HD171834 field; HR diagrams zone 1 zone 3 zone 2 zone 1 zone 2 zone 3 i < 16 AND V-I < 1.0 idea: we need to define a floating V-i (as a fct of V) segregation value to separate dwarf vs giant pops. could be defined as 15% line +0.3 in V-I. Or search for minimum in histogram V-I at different mags. -> program to create maps of densities dwarfs and giants

12. CW5 Berlin 12/2003 HD49933 field i < 16 Observations taken in feb 03 with strongly varying extinction and seeing up to 5” Photometry based on nightly zero- points (from WFS pipeline) is shown. Some pointings are clearly suffering strong extinction Re-calibration based on observed Landolt fields was performed

13. CW5 Berlin 12/2003 Photometric calibration of Feb 03 data mag WFS -mag cat Based on average offset mag WFS -mag cat [+color terms] of 30 Landolt-stars in L98 -> linear interpolation of zero-pt offsets applied to COROT field pointings lastly: Re-assembly of merged catalog: verifiy that each pointing added does not have offset >0.1mag in any color of overlapping stars relatively good conditions in short windows in 3rd night: |mag WFS -mag cat | <~ 0.02mag -> WFS calibration should be fine at photometric conditions? needs verification

14. CW5 Berlin 12/2003 before and after final phot. calibration HD49933 fld, mag i < 16

15. CW5 Berlin 12/2003 histograms against Vmag HD49933 after calibr, 20° 2, 0,43M * HD174866/N6633 19° 2, 2.15M * Nstar HD174866, 8° 2, 1,48M *

16. CW5 Berlin 12/2003 Summary Galactic center: Fields HD174866, HD171834 +NGC6633 are nearly complete and calibrated photometry has been inserted into COROT source catalogue. In four photometric nights (June 6-9, 2003) large parts of the new target fields HD175726 and HD177552 were observed, with reduction in progress. Six nights at INT/WFC conceded for summer 04. Galactic anticenter: Field HD49933 is mostly complete HD57006 only started. 10 nights at INT/WFC conceded for Dec 03/Jan 04.