Carla Maceroni INAFOsservatorio Astronomico di Roma 9 th

Carla Maceroni INAF-Osservatorio Astronomico di Roma 9 th Co. Ro. T Week, ESA, Noordwijk , December 6 -9, 2005

Composition & recent activity Two level structure: • 20 core members (specific tasks in AO 1 answer) - countries: Italy, Spain, Germany, Belgium, Brasil + other - (30% women) • Many associate members (general expression of interest, possible collaboration in specific topics). Coordinators: C. Maceroni & I. Ribas

BTT Webpage (thor. ieec. uab. es/binteam)

BTT Webpage (thor. ieec. uab. es/binteam)

BTT Webpage (thor. ieec. uab. es/binteam)

Pre-Corotsky field

BTT Webpage (thor. ieec. uab. es/binteam)

Coordinated answers to AP-AO 1 ü "A comprehensive study of close binaries observed by Corot“ (I. R. – C. M. & core members) A ‘large programme’ asking for all the light curves of the binaries which will be obtained by Co. Ro. T. Current status: preliminary task breakdown ü “Fundamental properties of known close binaries” ( C. M. – I. R. & subgroup of core m. ) very few targets Current status: preliminary target study

LP goals Determination of high-precision light curve elements for EBs and stellar fundamental properties of detached, semi-detached and contact binaries to sub-1% accuracy. Study of fine effects on EB light curves Characterization of the complete, magnitude-limited sample of EBs in the fields. Monitoring of cataclysmic variables. Analysis of the light curves of detached CBs with surface brightness inhomogeneities. Investigation of pulsating variables in CBs. Analysis of the new, unexpected CBs that COROT is certainly due to discover.

Who will study what: Light curve analysis / system modeling of: detached / contact binaries (Giménez, Maceroni, Ribas) Algol type binaries (Arévalo, Lázaro) Active binaries (Lanza, Montes, Gálvez) Close binaries with pulsating components (Gamorova, Lampens, Lehmann, Marconi, Mkrtichian, Ripepi) Cataclysmic binaries (De Martino, Janot-Pacheco, Silvotti) Statistical properties of CBs (Maceroni, Ribas, Mazeh) Stellar & pulsation models for binary components (Miglio, Montalban) detailed task breakdown in progress

Tools and complementary observations • Different programs for LC solutions: – WD-Phoebe, – Bina. Roche, – MARA (Modelling and Analysis of Rotators with Activity-affected light curves) • complementary multicolor photometry: Several possibilities (Teide, CT, BO……) • Spectroscopy: mainly application-dependent for EXO-field targets.

‘Small program’: Known Binaries AC field GU Mon Eco Binaries + DD Mon V 501 Mon DD & V 501 Mon mutually excluding!

Known EBs in the AC field… GU Mon • W UMa-type EB, P = 0. 95 d very hot presumably similar components • m. P = 11. 9 -12. 6 (Wackmann 1968) V= 11. 95, B-V=0. 36, E(B-V)=0. 65 (Moffat & Vogt 1975) • Sp B 8 Usually cited as a member of Dolidze 25 (Babu, 1983) FALSE! From the calibration P-L-C of contact binaries (Rucinski 1994, 2004): m-M (GU Mon) = 10. 48 (d=1. 2 Kpc) vs m-M (D 25) = 13. 60 (d=5. 2 Kpc) INTEREST: unusual contact binary with very hot components

Known EBs in the AC field… V 501 Mon • Bossen & Klawitter (1972, Ac. A, 22, 411) • Eccentric detached EB • Possibly mid-F type • P = 7. 02 days • m = 12. 7 -13. 2 mag • e 0. 1 Very little photometry Probably apsidal motion Spectroscopy: not yet (tidally induced pulsations? )

Known EBs in the AC field… DD Mon Qian et al. (1997, A&ASS, 125, 475) • Near (? ) contact EB • Single lined spectrum, F 5 • P = 0. 568 days • m = 11. 5 -12. 4 mag • e=0, q≈0. 5 , • partial eclipses ( i=76) Mass loss/exchange suggested by the low mass values for the derived radii (i. e. undermassive comp. ) and light curve V 501 Mon is the winner!

Next: • Strict interaction with eco-program (new binaries, GB observations, exchange of information) • ESO proposal for known binary target characterization. • Binary related HH?