arXiv:0902.4457v2 [astro-ph.EP] 5 May 2009 eety aglne l 20)rpr eetn seconda a 8 detecting using b report 80606 HD cy- (2009) for Kozai al. fr the et tidal of and Laughlin companion) combination stellar Recently, distant orbit the the present by from the (induced results cles that suggest b 80606 (2003) HD Murray of & Wu sky). the on rmr transits. primary h eisrnpsae hsipisa nlnto ftes the of inclination an near implies This passage. periastron the h rni fH 00 ceue ohpe nValentine’s on happen instruments used to simultaneously We scheduled 2009). February b 80606 (14 HD month o four of detection almost attempt transit to is the campaign planet observational the an of managed We period orbital the because ytm(ihH 00)wt eaainof separation a with 80607) HD (with system LDEsetorp yNe ta.(01.Ti sagiant a is This ( the (2001). orbit with eccentric al. discovered et M (4 was Naef planet by b 80606 HD spectrograph ELODIE planet extra-solar The Introduction 1. r vial tteCSvaaoyosfpt cdsarc.u-stras to ftp anonymous via CDS http: via the or t (130.79.128.5) at of available tables are Electronic 07A.PNP.CONS). (program consortium tteOsraor eHuePoec CR) rne yth by France, (CNRS), Haute-Provence de Observatoire the at otu C. Moutou, ovil,T. Forveille, a 0 2018 30, May ⋆ Astrophysics & Astronomy htmti n pcrsoi eeto ftepiaytra primary the of detection spectroscopic and Photometric ftast cu,opruiisfrdtcigte r rar are them detecting for opportunities occur, transits If ae nosrain aewt h .0mad19- telesc 1.93-m and 1.20-m the with made observations on Based i SOPHIE aaeswt h aetmns h nrs curdbefore occurred ingress The timings. same the with datasets ain efre tteOsraor eHuePoec,s Haute-Provence, extra-s de the Observatoire of the transit at primary performed the of vations detection the report We accepted ; Received 7 6 5 e words. Key ( star pl bright the a Orbiting between theory. tran relationship for the questions observed far by the is reinforces b 80606 radius HD migration. w Kozai detecti to misalignment the configuration this show confirmed, If measurements misalignment. velocity spin-orbit Radial refined. be to . n 72hus h aaalw h lntr aist be to radius planetary the allows data The hours. 17.2 and 9.5 4 3 1 2 = etod srfıia nvriaed ot,RadsEstr das Rua UK Porto, 4QL, do Astrof´ısica, EX4 Universidade Exeter, de Exeter, Centro of University Physics, of School bevtied e`v,Uiested e`v,5 Chemin Gen`eve, Gen`eve, 51 Universit´e de de Observatoire aoaor ’srpyiu,Osraor eGeol,U Grenoble, de Observatoire d’Astrophysique, Laboratoire bevtied at-rvne 47 an-ihll’Obs Saint-Michel 04870 Haute-Provence, de Observatoire ee 3 rnee-mail: CNRS& France 6110, 13, UMR cedex Marseille, de d’Astrophysique Laboratoire ntttdAtohsqed ai,UR05CR,Universi CNRS, UMR7095 Paris, de d’Astrophysique Institut 90 ◦ Jup n a and , 1 iha11dyobtlpro na extremely an on period orbital 111-day a with ) pcrgaho h 9-mtlsoe eosre h whole the observed We telescope. 193-cm the on spectrograph 4 H´ebrard, G. , efse X. Delfosse, , e lntr ytm ehius ailvlcte Techni – velocities radial Techniques: – systems Planetary = ∼ 0 5%poaiiyta h lntas shows also planet the that probability % 15 . 3.H 00 samme fabinary a of member a is 80606 HD 93). ulz D. Queloz, // cdsweb.u-strasbg.fr h 1-a-eidpae D866b 80606 HD planet 111-day-period the 2 aucitn.11954 no. manuscript ocy F. Bouchy, , 4 [email protected] eot M. Desort, , µ pte bevtosaround observations Spitzer m 5 ats N.C. Santos, , / cgi-bin 2 , 3 4 V ∼ gebre,A. Eggenberger, , arne A.-M. Lagrange, , = 20A ( AU 1200 ) toesopruiisfrnmru olwu studies. follow-up numerous for opportunities opens it 9), / qcat?J 7 S´egransan, D. , L e te othe to etter / SOPHIE A edata he iction. ∼ + ystem udcrooaetehptei htH 00 wsisunus its owes b 80606 HD that hypothesis the corroborate ould A ntrdu n h nietflxrcie rmtesa n op and star the from received flux incident the and radius anet ABSTRACT bg.fr opes lrpae D866b hnst htmti n spectrosco and photometric to thanks b, 80606 HD planet olar 20 usts a o bevd h uldrto ftetastw transit the of duration full The observed. not was so sunset ls 1072Pro Portugal Porto, 4150-762 elas, iesteJ ore,B 3 84 rnbe ee ,Franc 9, Cedex Grenoble, 38041 53, BP Fourier, niversit´e J. / mlaeul ihteCDcmr tte10c eecp an telescope 120-cm the at camera CCD the with imultaneously e alets 20Suen,Switzerland Sauverny, 1290 Maillettes, des raor,France ervatoire, no rgaeRsie-caglne Rossiter-McLaughlin prograde a of on of ry s. ′′ iigpae ntelnetpro eetdtdy t unus Its today. detected period longest the on planet siting e esrd( measured f ´ ire&MreCre 8i olvr rg,704Paris 75014 Arago, boulevard 98bis Curie, Marie & t´e Pierre 4 4 nv ePoec,3 u re´rcJlo-ui,138Ma Fr´ed´eric 13388 rue Joliot-Curie, 38 Provence, de Univ. ose I. Boisse, , oi,C. Lovis, , h tla uioiyi siae 0.84 estimated is luminosity stellar the a gravity, , luminosity, between relationship ta.20,Vlni&ice 05.Teselrms a ee 0 be get can we and stellar isochrones The using 2005). timated &Fischer Valenti 2004, al. et log rdce pcsfrtepiaytasto D866 were 80606b aro HD observations carried of We (2009). transit al. et primary Laughlin the by given for epochs Predicted 80606b HD of transit photometric The 2. (Sa Gyrs 7.6 to 1.7 of interval age an Chromospheri gives determination. tivity radius and mass over erations n aiswt uioiyadtmeaue edrv radi a derive we 0 temperature, and luminosity with radius ing rmteltrtr ie ne an gives literature the from eue noraayi ftetastdt rsne here- presented by measured data parallax transit a with the 17 star of G5-type of a Hipparcos analysis is 80606 our HD after: in used we b, 80606 Rossite HD the of through transit spectroscopy in primary the e as McLaughlin the well and of as telescope, photometry detection in 120-cm the the report to at camera (OHP) SOPHIE CCD Haute-Provence de the Observatoire France: the of telescopes two . 98 5 E us htmty–Sas niiul D80606 HD individual: Stars: – photometry ques: dy S. Udry, , g ercl h tla hrceitc ftepiaysa,w star, primary the of characteristics stellar the recall We ditor ± f4 of geso h rni n atal t eta at nboth in part, central its partially and transit the of egress R 0 p . 7R 07 = pcrgaha h .3mtlsoe hsalw us allows This telescope. 1.93-m the at spectrograph . 45 2 5 0 ofis X. Bonfils, , ao,M. Mayor, , . ⊙ 9 ± 5 hs envle eeotie fe eea it- several after obtained were values mean These . ff ± n ia-ajr A. Vidal-Madjar, and , ect. 0 0 ± . 5adahg ealct f03 e (Santos dex 0.33 of metallicity high a and 05 . 0R 10 a.Acmiaino pcrsoi data spectroscopic of compilation A mas. 5 Jup n te aaeeso h system the of parameters other and ) 4 5 rvlo,D. Gravallon, , ee F. Pepe, , ff cietmeaueo 5574 of temperature ective ff c,adpoieahn fa of hint a provide and ect, ⋆ 5 ere,C. Perrier, , . ± 98 2 .3L 0.13 ± 3 herih D. Ehrenreich, , 0 . 0M 10 e ⊙ al small ually sbetween as ff a orbital ual i obser- pic ial,relat- Finally, .

ta.2005). al. et e stof nsit 4 c n new ens France , ot F. Pont, , ⊙ S 2018 ESO rseille sn the Using . the d dmass, nd ± 0K, 50 sof us ac- c hich und 6 4 s- , , r- , 2 C. Moutou et al.: Primary transit of HD 80606 b the expected transit epoch JD=2,454,876.5with the 120-cm tele- Modelling the primary transit lightcurve of HD80606b is scope at OHP, equipped with a 12 arcmin × 12 arcmin CCD done in the first place using models of circular orbits, to con- camera. The Bessel R filter and a neutral density were inserted, strain the inclination and the radius ratio. The Universal Transit to insure unsaturated, focused images of the V = 9 target. We Modeler (Deeg 2008) is used, including the limb-darkening co- obtained 326 frames on 13 Feburary 2009 and 238 frames on efficients of Claret (2000) for the r′ filter, and parameters of the the preceeding night, for comparison. Typical exposure times orbits given in the next section. Figures 1 and 2 show three range between 60 sec on the first night and 20-30 sec on the transit models superimposed to the data, corresponding to im- second. Aperture photometry was then performed on both data pact parameter b ranging from 0 to 0.91 or inclinations ranging sequences. Aperturesof 8 and 6 pixels were used for the first and from 89.2 to 90.0 deg. The O − C residuals depicted in Fig.2 second observing nights, respectively. The secondary compan- correspond to an average transit duration of 13.5 hours, with ion HD80607 is taken as a reference for HD80606. Both stars b = 0.75 and rms of 0.0023. The transit depth imposes a ra- are separated by 24 pixels, which prevents contamination even dius ratio Rp/R∗ of 0.094 ± 0.009. The planet radius is then esti- using simple aperture photometry. The sky background is evalu- mated to be 0.9±0.10 RJup. To match the full transit lightcurve, a ated in rings of about 12-15 pixel radii. The resulting lightcurve model including eccentricity would be required. The asymmetry is shown in Fig. 1 (upper panel) with all data included. The data of the ingress and egress should be detected and properly fitted, quality is significantly better during the transit night, because of for instance. Since we have a partial transit, the approximation different seeing conditions. The rms is about 0.0023 and 0.0030, of the circular modelling is acceptable here, if one takes the rel- respectively. ative projection of the transit angle and the line of sight into ac- An egress is clearly detected in the data sequence obtained count. In a further study, we plan to investigate the modelling of during the night 13-14 February. A shift of almost one half tran- the asymetric transit by including the eccentric orbit. We do not sit is observed, in comparison to expected ephemeris. Long-term expect major differences compared to the simple fit performed systematics are observed in the lightcurve and removed by a here, before new, more complete photometric data are obtained. polynomial function of the airmass, with the criterion of get- ting a flat section of the out-of-transit flux. This correction does not strongly affect the transit shape. It is checked on the 12-13 February sequence that long-term fluctuations are low (not cor- rected for in Fig. 1). The beginningof the transit sequence unam- biguously shows that we do not detect the ingress of the transit. The first hour of the sequence indicates a slight decrease but the data are quite noisy due to the low object’s elevation, and this may be introduced by the correction for airmass variations. We observed in total 7 hours during transit on the second night, and 3.4 hours after the transit. In addition, we gathered 9.8 hours out of transit on the first night.

Fig. 2. Zoom-in plot on the photometric transit and the three models with the impact parameter ranging from 0 to 0.91. The residuals are shown below, with an offset of 0.02 on the Y-axis for clarity,and they correspondto the mean modelwith b = 0.75.

3. The spectroscopic transit of HD 80606b We observedHD80606 with the SOPHIE instrument at the 1.93- m telescope of OHP. SOPHIE is a cross-dispersed, environmen- tally stabilized echelle spectrograph dedicated to high-precision radial velocity measurements (Bouchy et al. 2006; Perruchot et Fig. 1. Photometry (top) and radial velocities (bottom) of al. 2008). We used the high-resolution mode (resolution power HD80606 from 12 to 14 February, 2009, obtained at OHP with R = 75, 000) of the spectrograph and the fast-readout mode of the 120-cm and 193-cm telescopes, respectively. The planetary the CCD detector. The two 3”-wide circular apertures (optical transit is detected in both datasets at the same timing. Top: fibers) were used, the first one centred on the target and the sec- Superimposed are the two extreme (b = 0 in red-dashed, and ond one on the sky to simultaneously measure its background. b = 0.91 in green-long-dashed) and the mean (in blue-dotted, This second aperture, 2’ away from the first one, allows us to b = 0.75) models that correspond to our data set. Bottom: The check that there is no significant pollution due to moonlight on orbital solution is overplotted (solid line, Table 1), together with the spectra of the target. We obtained 48 radial velocity mea- Rossiter-McLaughlin effect models presented in Table 2, in red- surements from 8 to 17 February 2009, including a full sequence dashed (b = 0, λ = 0◦), blue-dotted (b = 0.75, λ = 63◦), and during the night 13 February (BJD = 54876), when the possible green-long-dashed lines (b = 0.91, λ = 80◦). transit was expected to occur according to the ephemeris. The exposure times range from 600 to 1500 sec, insuring a constant C. Moutou et al.: Primary transit of HD 80606 b 3 signal-to-noise ratio. This observation was performed in parallel to the photometric ones. The sequence of the transit night is plotted in Fig. 1, lower panel, together with the measurement secured the previousnight. The Keplerian curve expected from the orbital parameters is overplotted. The radial velocities of the 13 February night are clearly blue-shifted by ∼ 10 ms−1 from the Keplerian curve in the 1st half of the night, then match the Keplerian curve in the 2nd half of the night. This is the feature expected for a planet transiting on a prograde orbit, according to the Rossiter- McLaughlin (RM) effect. This effect occurs when an object tran- sits in front of a rotating star, causing a spectral distortion of the stellar lines profile, and thus resulting in a Doppler-shift anomaly (Ohta et al. 2005; Gim´enez et al. 2006b; Gaudi & Winn 2007). On the RM feature of HD80606b (Fig. 1), the third and fourth contacts occurred at BJD ≃ 54876.45 and BJD ≃ 54876.55, respectively, whereas the first contact occurred before sunset and was not observed. These timings agree with those of the photometry (Sect. 2 and Fig. 2) and the detection of the Fig. 3. Phase-folded radial velocity measurements of HD 80606 Rossiter-McLaughlin anomaly is unambiguous. as a function of the orbital phase, and Keplerian fit to the The Keplerian curve in Fig. 1 corresponds to the orbital pa- data. ELODIE data in blue, Keck data in red, SOPHIE data in rameters that we refined for HD80606b. We used the SOPHIE green. Orbital parameters corresponding to this fit are reported measurements performed out of the transit, as well as 45 Keck in Table 1. The inset shows a zoom around the transit phase. One measurements (Butler et al. 2006) and 74 ELODIE measure- Keck spectrum was obtained 1hr after transit. ments (55 published by Naef et al. (2001) and 19 additional measurements obtained from BJD = 52075 to 52961). We al- lowed free radial-velocity shifts between the three datasets. We could be slightly overestimated here due to the high metallicity used the constraint of the secondary transit given by Laughlin of HD80606. We decided to fix this value and to explore the dif- = . ± . et al. (2009) (Te 2454424 736 0 003 HJD). We also used ferent values of inclination angle i to estimate the spin-orbit λ our constraint on the primary transit considering that the end of angle. We see in Table 2 that, if the transit is not central, then the = . ± . transit is Tegress 2454876 55 0 03 BJD. From these con- RM fit suggests that the spin-orbit angle is not aligned. traints, we estimated that the inclination of the system is from ◦ ◦ 90 (Tt = 2454876.20 BJD with 17.2 h duration) to 89.2 (Tt = 2454876.32 BJD with 9.4 h duration). Assuming those constraints, we adjusted the Keplerian orbit. The dispersionof the radial velocities aroundthis fit is 8.6 m s−1, 4. Discussion and conclusion and the reduced χ2 is 1.4. The obtained parameters are reported in Table 1. They agree with those of Laughlin et al. (2009), ex- Despite the low probability of a 111-day period system being cept for the period, where there is a 3-σ disagreement. The full seen edge-on at both at the primary and the secondary transit data set and orbital solution are plotted in Fig. 3. We note that no phases (about 1% in the case of HD80606b), the data acquired anterior data was obtained during the transit by any instrument, as shown in the inset of Fig. 3. Table 1. Fitted orbit and planetary parameters for HD80606b. To model the RM effect, we used the analytical approach developed by Ohta et al. (2005). The complete model has 12 Parameters Values and 1-σ error bars Unit parameters: the six standard orbital parameters, the radius ratio −1 Vr (Elodie) 3.788 ± 0.002 km s r /R∗, the orbital semi-major axis to stellar radius a/R∗ (con- −1 p Vr (SOPHIE) 3.911 ± 0.002 km s strained by the transit duration), the sky-projectedangle between P 111.436 ± 0.003 days the stellar spin axis and the planetary orbital axis λ, the sky- e 0.934 ± 0.003 projected stellar rotational velocity v sin I, the ω 300.6 ± 0.4 ◦ i, and the stellar limb-darkening coefficient ǫ. For our purpose, K 472 ± 5 m s−1 we used the orbital parameters and photometric transit param- T0 (periastron) 2 454 424.857 ± 0.05 BJD † eters as derived previously. We fixed the linear limb-darkening Mp sin i 4.0 ± 0.3 MJup † coefficient ǫ = 0.78, based on Claret (2000) tables for filter g′ a 0.453 ± 0.015 AU Tt (primary transit) 2 454 876.27 ± 0.08 BJD and for the stellar parameters derived in Sect. 1. Our free param- ‡ eters are then λ, v sin I, and i. As we observed a partial transit, Te (secondary transit) 2 454 424.736 ± 0.003 BJD t14 9.5 − 17.2 hours there is no way to put a strong constraint on the inclination i. t 8.7 − 15.7 hours We then decided to adjust λ for different values of i in the range 23 M 0.98 ± 0.10 M⊙ 89.2 - 90 ◦. The results of our fits (Table 2 and Fig. 1, lower ⋆ R⋆ 0.98 ± 0.07 R⊙ panel) first show that the stellar rotation is prograde relative to Rp/R∗ 0.094 ± 0.009 ◦ ◦ the planet orbit. Assuming i = 90 and λ = 0 , the projected Rp 0.9 ± 0.10 RJup rotation velocity of the star v sin I determined by our RM fit b 0.75 (-0.75, +0.16) is 2.2 kms−1. This agrees with the value 1.8 kms−1 obtained i 89.6(−0.4, +0.4) ◦ by Valenti & Fisher (2005), as well as our spectroscopic de- †: using M⋆ = 0.98 ± 0.10 M⊙ termination (2-3 kms−1) from SOPHIE spectra. This latest one ‡: from Laughlin et al. (2009) 4 C. Moutou et al.: Primary transit of HD 80606 b

Table 2. Parameter sets for the Rossiter-McLaughlin effect mod- and Garcia-Melendo & McCullough (2009) independently con- els. firm the detection of the photometric transit. In addition, MEarth observations (D. Charbonneau, priv. comm. and oklo.org) held i transit duration Ttransit spin-orbit λ χ2 in Arizona show a flat lightcurve of HD80606, which limits the (deg) (hours) BJD -2454000 (deg) transit duration to less than 12 hours, hence reinforcing evidence 90.0 17.2 876.20 0 33.0 of a spin-orbit misalignment (solutions of red and blue models 89.6 15.5 876.24 63 25.3 in Fig. 1 are rejected). The grazing eclipse configuration would 89.2 9.4 876.32 86 33.4 also result in a slightly larger planetary radius. Further analyses will follow in a forthcoming paper. at the Observatoire de Haute-Provence and presented here show this alignment unambiguously. With a partial transit observed, we were able to constrain the orbital parameters, including the inclination with a precision of ≃ 0.4◦, and to measure the plane- tary radius. The error bars of our measurements should be taken with caution, however, and the system’s parameters slightly re- vised when more complete data is obtained, since systematic noise is more difficult to correct with incomplete transits. The planet has a low radius (0.9 RJup) considering its mass (4MJup). Since it is also by far the transiting receiving the lower irradiation from its parent star, it is tempting to see its small radius as reinforcing the explanation of anomalously large hot as caused primarily to stellar irradiation, as proposed for instance by Guillot & Showman (2002). Figure 4 shows the Fig. 4. Radius of transiting gas giant planets as a function of increasingly clear correlation between equilibrium temperature 1/2 2 −1/8 the equilibrium temperature (Teq ∼ T∗(R∗/a) (1 − e ) ). and size for transiting gas giants. The relation holds for both HD80606 is circled. Its position reinforces the correlation be- massive planets (> 2MJup) and -like planets. Tidal effects tween incident flux and radius. All transiting gas giants are in- (Jackson et al., 2007) may play a role in the observed radius of cluded above 0.4 M . The red circles show the planets with HD80606b. The high metallicity of the parent star also helps Jup mass higher than 2 MJup. They follow the same tendency as provide refractory material for a massive core, although the re- Jupiter-like planets (black squares). quired enrichment would be beyond actual expectations. More theoretical development is needed to reproduce the system’s pa- rameters, taking the whole history of orbital evolution and vari- ations in the irradiation conditions into account. Most of the ∼ 60 known transiting planets are orbiting close Acknowledgements. We are extremely grateful to Greg Laughlin for calling at- tention to the potential transit and encouraging observations. We thank the tech- to their hosting stars. Only 5 of them have periods longer than nical team at Haute-Provence Observatory for their support with the SOPHIE 5 days, the most distant from its star being HD17156b, on a instrument and the 1.93-m and 1.20-m telescopes. Financial support for the 21.2-dayperiod. HD80606b has by far the longest period (111.4 SOPHIE Consortium from the ”Programme national de plan´etologie” (PNP) of days). It may be compared to other planetary systems with a CNRS/INSU, France, and from the Swiss National Science Foundation (FNSRS) are gratefully acknowledged. We also acknowledge support from the French massive planet in an eccentric orbit: HD17156, HAT-P-2, and National Research Agency (ANR). N.C.S. would like to thank Fundac¸˜ao para XO-3. HD80606b hasa smaller radiusthan those planets, which a Ciˆencia e a Tecnologia, Portugal, for the support through programme Ciˆencia can be related to the migration history or to the changes in 2007 and project grant reference PTDC/CTE-AST/66643/2006. stellar irradiation along the orbit (Laughlin et al, 2009). The shape of the Rossiter-McLaughlin anomaly shows that the or- bit of HD80606b is prograde, and suggests that it could be sig- References nificantly inclined relative to the stellar equator. Since a high Bouchy, F., and the Sophie team, 2006, in Tenth Anniversary of 51 Peg-b: initial relative inclination is a key requirement for Kozai mi- Status of and prospects for studies, eds. L. Arnold, F. Bouchy gration to work (Wu & Murray 2003), this observation is not & C. Moutou, 319 Butler, R.P., Wright, J.T., Marcy, G.W. et al., 2006, ApJ 646, 505 surprising. Tighter constraints on the spin-orbit misalignment in Claret, A. 2000, A&A, 363, 1081 HD80606 may support the Wu & Murray formation scenario Deeg, H.J., 2008, in ’Transiting Planets’, IAU Symposium 253, in press and may provide compelling evidence that the orbital evolution Fabrycky, D. C., & Winn, J. N. 2009, ApJ, in press, astrop-ph/0902.0737 of HD80606b was once dominated by the binary companion. Fossey, S., Waldemann, I. & Kipping, D., 2009, MNRAS, in press, astrop- Among the 11 other transiting planets with Rossiter-McLaughlin ph/0902.4616 Garcia-Melendo, E. & McCullough, P., 2009, ApJ, in press, astrop-ph/0902.4493 measurements, the only system to show a significant spin-orbit Gaudi, B.S., & Winn, J.N., 2007, ApJ, 655, 550 misalignment is XO-3, another massive and eccentric planet Gim´enez, A., 2006b, ApJ, 650, 408 (H´ebrard et al. 2008; Winn et al. 2009). HAT-P-2b is aligned Guillot T. & Showman, A., 2002, A&A 385, 156 (Winn et al. 2007; Loeillet et al. 2008). H´ebrard, G., Bouchy, F., Pont, F., et al. 2008, A&A, 481, 52 Burrows, A., Hubeny, I., Budaj, J. & Hubbard, W.B., 2007, ApJ661, 502 HD80606b is thus a new Rosetta stone in the field of plane- Jackson, B., Barnes, R., & Greenberg, R., 2008, MNRAS 391, 237 tary transits. By orbiting a bright star (V = 9), it opens opportu- Laughlin, G., Deming, D., Langton, J., et al. 2009, Nature, 457, 562 nities for numerous follow-up studies, including: observation of Loeillet, B., Shporer, A., Bouchy, F., et al. 2008, A&A, 481, 529 a full photometric transit from space or multi-site campaigns to Naef, D., Latham, D. W., Mayor, M., et al. 2001, A&A, 375, 27 measure a complete spectroscopic transit sequence. Ohta, Y., Taruya, A, & Suto, Y., 2005, ApJ, 622, 1118 Perruchot, S., Kohler, D., Bouchy, F. et al., 2008, SPIE 7014, 17 After submission, we learned that other observations of this Santos, N.C., Israelian, G. and Mayor, M., 2004, A&A 415, 1153 system had been obtained on the same day. Fossey et al (2009) Saffe, C., G´omez, M. & Chavero, C., 2005, A&A443, 609 C. Moutou et al.: Primary transit of HD 80606 b 5

Valenti, J.A. & Fischer, D.A., 2005, ApJS 159, 141 Winn, J. N., Holman, M. J., Bakos, G. A., et al. 2007, ApJ, 665, L167 Winn, J. N., Johnson, J.A., Fabrucky, D. et al. 2009, subm., astrop-ph/0902.3461 Wu, Y., & Murray, N. 2003, ApJ, 589, 605