Comments on: CoRoT-7b http://oklo.org/2009/02/04/corot-7c/ characterizing planetary systems Fri, 18 Nov 2011 22:27:52 +0000 hourly 1 http://wordpress.org/?v=3.2.1 By: greg http://oklo.org/2009/02/04/corot-7c/comment-page-1/#comment-13733 greg Thu, 05 Feb 2009 05:00:47 +0000 http://oklo.org/?p=315#comment-13733 This just in! Another oklo.org agent on location in Paris has filed a report with additional details: "... I thought I would send you my notes from Rouan's & Bouchy's talks (no guarantee of being correct): B) Rouan: Has CoRoT discovered the first transiting Super-Earth around a main sequence star? Corot-Exo-7b: LRa01 135 days. m_V=11.7 LRa01_E2_165 - bright CoRoT star! Detected in 3 colors; 32 second sampling. K0V, 5250 K, 0.87 R_sun, 0.93 M_sun, M/H=0.05, D=130+- 30 pc, 5 < T < 8 Gyr, active star - H&K Ca emission 2% modulation activity. Spot crossing time is 23 days - clearly seen. Alonso detected after 40 days in alarm mode. Folded lightcurve shows an apparent transit - 153 transits gives clear signal. P=0.8536 days, 0.035%. Follow-up: 1) Spectroscopy shows it is a main-sequence star. 2) on/off photometry - 99.63% of light in Corot PSF is from E2_0165 contribution from other stars: 0.24% V=15.5 @ 17" NE; <0.1% V=13.6 @ 30" SE -> no background eclipsing binaries. 3) Imaging in good seeing: CFHT-MEGACAM g-band. Two faint stars at 4.5 & 5.5" - Delta m = 10 -> too faint to cause a 3.5x10^-4 Delta F/F. 4) AO imaging - NACO at VLT - J-band - rotated & subtracted off E2_165. stars excluded >0.5" except. J=18.4-18.7 stars at > 4", Delta m(g) = 10 (CFHT) - > too faint to be background eclipsing binary. 5) IR spectra w/ CRIRES (AO) - Triple system? 0.3" slit, R=60,000, K-band (CO-overtones). \Delta m_K is small between M & K stars, CO lines strong in M stars. No late K or earlier than M6 & brighter than K=12.3 within 0.3" - > exclude triple system. 6) X-ray activity: exclude later type M stars - excluded by XMM data. 7) CoRoT colors: transit light curve is achromatic in Corot B,R,V 8) AO Imaging: Triple with same colors as Corot star. Star must be < .035. NACO-VLT add mV=16.7 at .2" & .3" - would be detected in AO imaging. 9) RV with HARPS - Bouchy - No stellar, sub-stellar, or jupiter mass object. M < 11 M_Earth. Data reduction continuing. Peak at 0.851 days! clear peak! a=0.017 AU = 2.8 R_*. R_pl = 1.76 R_Earth. b = 0.86 +- 0.09; Rp/R_* = 0.02. 1% tidal elongation; T = 1100-2000 K depending on albedo. If M > 6 M_earth, rocky - solid or liquid lava? ocean if M < 5 M_earth. Atmosphere?? Would escape in < 1 Gyr. C) Bouchy: Spectroscopy of Exo-7b. CoRoT-Exo-7b: 80 measurements of 30-45 min, S/N ~ 50, sig_RV ~ 1.5 m/s. 30 m/s jitter (active star). Longer period RV due to stellar activity. K ~ 7.5 m/s at CoRoT period! Four Keplerian orbits - P=23 days - activity, 9 day period - activity. At minimum of activity K=7.4 m/s at P=0.8535 d (may be as low as K=4.5 m/s). 5.3-10.6 M_earth; 3.7 < K < 7.5 m/s. Possible second planet at 3.7 days K ~ 5m/s(?) - 4x period of inner planet. Neptune-like planet. No CCF or FWHM variation on these periods. Slight correlation between bisector & RV. May indicate a blend" This just in! Another oklo.org agent on location in Paris has filed a report with additional details:

“… I thought I would send you my notes from Rouan’s & Bouchy’s talks (no guarantee of being correct):

B) Rouan: Has CoRoT discovered the first transiting Super-Earth around a main sequence star?

Corot-Exo-7b: LRa01 135 days. m_V=11.7 LRa01_E2_165 – bright CoRoT star!

Detected in 3 colors; 32 second sampling. K0V, 5250 K, 0.87 R_sun, 0.93 M_sun, M/H=0.05, D=130+- 30 pc, 5 < T < 8 Gyr, active star - H&K Ca emission

2% modulation activity. Spot crossing time is 23 days - clearly seen. Alonso detected after 40 days in alarm mode.

Folded lightcurve shows an apparent transit - 153 transits gives clear signal. P=0.8536 days, 0.035%.

Follow-up:

1) Spectroscopy shows it is a main-sequence star.
2) on/off photometry - 99.63% of light in Corot PSF is from E2_0165 contribution from other stars: 0.24% V=15.5 @ 17" NE; <0.1% V=13.6 @ 30" SE -> no background eclipsing binaries.

3) Imaging in good seeing: CFHT-MEGACAM g-band.
Two faint stars at 4.5 & 5.5″ – Delta m = 10 -> too faint to cause a 3.5×10^-4 Delta F/F.

4) AO imaging – NACO at VLT – J-band – rotated & subtracted off E2_165. stars excluded >0.5″ except. J=18.4-18.7 stars at > 4″, Delta m(g) = 10 (CFHT) – > too faint to be background eclipsing binary.

5) IR spectra w/ CRIRES (AO) – Triple system? 0.3″ slit, R=60,000, K-band (CO-overtones). \Delta m_K is small between M & K stars, CO lines strong in M stars. No late K or earlier than M6 & brighter than K=12.3 within 0.3″ – > exclude triple system.

6) X-ray activity: exclude later type M stars – excluded by XMM data.

7) CoRoT colors: transit light curve is achromatic in Corot B,R,V

8) AO Imaging: Triple with same colors as Corot star. Star must be < .035. NACO-VLT add mV=16.7 at .2" & .3" - would be detected in AO imaging.

9) RV with HARPS - Bouchy - No stellar, sub-stellar, or jupiter mass object. M < 11 M_Earth. Data reduction continuing. Peak at 0.851 days! clear peak!

a=0.017 AU = 2.8 R_*. R_pl = 1.76 R_Earth. b = 0.86 +- 0.09; Rp/R_* = 0.02.

1% tidal elongation; T = 1100-2000 K depending on albedo. If M > 6 M_earth, rocky – solid or liquid lava? ocean if M < 5 M_earth. Atmosphere?? Would escape in < 1 Gyr.

C) Bouchy: Spectroscopy of Exo-7b.

CoRoT-Exo-7b: 80 measurements of 30-45 min, S/N ~ 50, sig_RV ~ 1.5 m/s. 30 m/s jitter (active star). Longer period RV due to stellar activity. K ~ 7.5 m/s at CoRoT period! Four Keplerian orbits – P=23 days – activity, 9 day period – activity. At minimum of activity K=7.4 m/s at P=0.8535 d (may be as low as K=4.5 m/s). 5.3-10.6 M_earth; 3.7 < K < 7.5 m/s.

Possible second planet at 3.7 days K ~ 5m/s(?) – 4x period of inner planet. Neptune-like planet.

No CCF or FWHM variation on these periods.

Slight correlation between bisector & RV. May indicate a blend”

]]> By: greg http://oklo.org/2009/02/04/corot-7c/comment-page-1/#comment-13719 greg Wed, 04 Feb 2009 18:29:15 +0000 http://oklo.org/?p=315#comment-13719 Post has been updated to reflect an improved sky position of the CoRoT galactic anticenter field. Our agent at the conference writes: "The planet is in the so called LRa01 run, the coordinates are public available in this web page http://corot.oamp.fr/pages/targets.html" Post has been updated to reflect an improved sky position of the CoRoT galactic anticenter field. Our agent at the conference writes:

“The planet is in the so called LRa01 run, the coordinates are public
available in this web page
http://corot.oamp.fr/pages/targets.html“

]]> By: Centauri Dreams » Blog Archive » COROT Finds a Small, Rocky World http://oklo.org/2009/02/04/corot-7c/comment-page-1/#comment-13718 Centauri Dreams » Blog Archive » COROT Finds a Small, Rocky World Wed, 04 Feb 2009 15:23:32 +0000 http://oklo.org/?p=315#comment-13718 [...] Be sure to read systemic’s take on COROT-Exo-7b, from which this: Everything about CoRoT-7b reemphasizes the fact that planets are [...] [...] Be sure to read systemic’s take on COROT-Exo-7b, from which this: Everything about CoRoT-7b reemphasizes the fact that planets are [...]

]]> By: greg http://oklo.org/2009/02/04/corot-7c/comment-page-1/#comment-13716 greg Wed, 04 Feb 2009 15:05:33 +0000 http://oklo.org/?p=315#comment-13716 Hi devicerandom, Yes, thanks! I've corrected the error. On exoplanet.eu. there was also a CoRoT-exo-7c listed, but I think that was a mistake... G Hi devicerandom,

Yes, thanks! I’ve corrected the error.

On exoplanet.eu. there was also a CoRoT-exo-7c listed, but I think that was a mistake…

G

]]> By: devicerandom http://oklo.org/2009/02/04/corot-7c/comment-page-1/#comment-13715 devicerandom Wed, 04 Feb 2009 14:40:29 +0000 http://oklo.org/?p=315#comment-13715 Isn't it Corot-7b , not c? Or did I miss something? Isn’t it Corot-7b , not c? Or did I miss something?

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