| Planet [EPE link] | Spin-orbit alignment λ ≡ -β | Error | ADS references |
[1] The study of Czesla et al. (2012) provides the
first measurement ever of a chromospheric Rossiter-McLaughlin effect, showing that the chromosphere of CoRoT-2 has a scale of about 105 km.
[2] Nutzman et al. (2012) were the first to use star
spots for the measurement of the spin-orbit misalignment. Advantageously, their method can be used to derive the true geometry and not only the
sky-projection.
[3] The position angle of the star Fomalhaut was measured to be 65° (±3°), while the disk angle was
observed to be 156° (±0.3°). Thus, the stellar rotation axis is almost perfectly perpendicular to
the disk plane. So far, no planet of this system shows transits.
[4] A set of two solutions for the stellar obliquity of Hat-P-11 is given in Sanchis-Ojeda et al. (2011).
[5] The Narita et al. (2009) results formally supersede those by Narita et al. (2008).
[6] Planet Kepler-16(AB)b orbits a stellar binary. The measurements of Winn et al. (2011) were taken during the transit of
the secondary star (B) in front of the primary star (A).
[7] Désert et al. (2011) determined the maximum
stellar obliquity from observations of the stellar spots occasionally being occulted by the planet.
[8] This misalignment between the stellar spin and the planetary orbit plane was the first determined by gravity darkening in the transit light curve. It is not the
sky-projected but the true angle (in literature called 'obliquity', ψ). However, the light curve is also compatible with a retrograde orbit of 124° (±4°).
[9] While the Holt-Rossiter-McLaughlin (HRM) effect during the transit of Venus in front of the Sun on June 6, 2012 has been observed, it has not been determined by those observations.
The sky-projected spin-orbit misalignment had been known before.
[10] Further constraints on the obliquities of WASP-1b and WASP-2b, some of which contradict the conclusions from the authors given above, are given by
Albrecht et al. (2011).
Angles are given in terms of λ as defined in Ohta et al. (2005). It is sometimes confused with the angle
β ≡ -λ, as defined by Hosokawa (1953) and
Giménez et al. (2006). Howsoever,
in a physical sense the definition of the algebraic sign is arbitrary. Among the systems listed above, those with substantial misalignments (> π/8 = 22.5°) are marked in bold,
but pay attention to the errors!
The analysis of the HRM effect of WASP-23b, given by Triaud et al. (2011),
is not listed above since their data yields ambiguous results about the sky-projected spin-orbit misalignment.
Helpful résumés of spin-orbit measurements and the Rossiter-McLaughlin effect are given by
Fabrycky & Winn (2009)
and
Pont et al. (2009). For a thorough description of the in-transit RV variation, the
convective blueshift needs to be considered (Shporer and Brown 2011). An alternatve
approach to measure the sky-projected spin-orbit misalignment is the inhomogeneous distribution of effective temperature on the star, induced by gravitational
darkening on the star (Szabó et al. 2011).
This site makes intense use of the Extrasolar Planets Encyclopaedia
and the SAO/NASA Astrophysics Data System (ADS). I thank Jean Schneider, Olivier Absil, Elaine Simpson, John Johnson,
Yasushi Suto, Joshua Winn, Michael Perryman, and Alexis Smith for their helpful comments.
Questions, remarks and corrections are much appreciated. If you use this website for your publication, it would be kind to note "This study has made use of René Heller's Holt-Rossiter-McLaughlin Encyclopaedia (www.aip.de/People/RHeller)."
Download: HRM_encyclopaedia.txt
Lardner, D., 1858, "Hand-Books of Natural Philosophy and Astronomy", Third Course, Blanchard and Lea, Philadelphia, Chp XXVII (as cited by Howell et al. 1999)
Holt, J. R., 1893, Astronomy and Astrophysics, XII, "Spectroscopic Determination of Stellar Rotation" [cover], [.pdf] (I found this prediction of the later Rossiter-McLaughlin effect, observed in 1924, when I was delving among historical books in the library of the Hamburger Sternwarte in 2009. So far, this paper is not listed on ADS. For reference, you may want to use this Holt_bibtex.bib citation as we used it in Heller et al. 2009.)
Schlesinger, F., 1910, PAllO, 1, 123 [ADS] (measurement of the later Rossiter-McLaughlin effect, observed 1924)
Rossiter, R. A., 1924, ApJ, 60, 15 [ADS]
McLaughlin, D. B., 1924, ApJ, 60, 22 [ADS]
Struve, O., 1952, The Observatory, 72, 199 [ADS] (on exoplanet detection)