J/A+A/550/A53 Public code ARoME for modeling the RM effect (Boue+, 2013)
New analytical expressions of the Rossiter-McLaughlin effect adapted to
different observation techniques.
Boue G., Montalto M., Boisse I., Oshagh M., Santos N.C.
<Astron. Astrophys. 550, A53 (2013)>
=2013A&A...550A..53B 2013A&A...550A..53B
ADC_Keywords: Models ; Planets
Keywords: techniques: spectroscopic - instrumentation: spectrographs -
planetary systems - methods: analytical - methods: data analysis
Abstract:
The Rossiter-McLaughlin (hereafter RM) effect is a key tool for
measuring the projected spin-orbit angle between stellar spin axes and
orbits of transiting planets. However, the measured radial velocity
(RV) anomalies produced by this effect are not intrinsic and depend on
both instrumental resolution and data reduction routines. Using
inappropriate formulas to model the RM effect introduces biases, at
least in the projected velocity Vsini compared to the spectroscopic
value. Currently, only the iodine cell technique has been modeled,
which corresponds to observations done by, e.g., the HIRES
spectrograph of the Keck telescope. In this paper, we provide a simple
expression of the RM effect specially designed to model observations
done by the Gaussian fit of a cross-correlation function (CCF) as in
the routines performed by the HARPS team. We derived also a new
analytical formulation of the RV anomaly associated to the iodine cell
technique. For both formulas, we modeled the subplanet mean velocity
v_p and dispersion beta_p accurately taking the rotational broadening
on the subplanet profile into account. We compare our formulas adapted
to the CCF technique with simulated data generated with the numerical
software SOAP-T and find good agreement up to Vsini<20km/s. In
contrast, the analytical models simulating the two different
observation techniques can disagree by about 10sigma in Vsini for
large spin-orbit misalignments. It is thus important to apply the
adapted model when fitting data.
Description:
This library is designed to generate analytical Rossiter-McLaughlin
(RM) effects produced by observation techniques. It models the
Doppler-shift of a star during a transit measured by the following
techniques:
* fit of a cross-correlation function by a Gaussian function,
* fit of an observed spectrum by a modeled one,
* weighted mean.
This library provides a C interface and, optionally, a Fortran 77 or
2003 interface to be called by the application.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
arome.pdf 512 621 Information for installation and usage
arome-1.0.0.tar 2099 65383 tar containing all the source files
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Acknowledgements:
Gwenael Boue, gwenael.boue(at)astro.up.pt
(End) Gwenael Boue [CAUP, Portugal], Patricia Vannier [CDS] 08-Jan-2013