Stellar surface magneto-convection as a source of astrophysical noise. II. Center-to-limb parameterization of absorption line profiles and comparison to observations

Cegla, HM, Watson, CA, Shelyag, Sergiy, Chaplin, WJ, Davies, GR, Mathioudakis, M, Palumbo, ML, Saar, SH and Haywood, RD 2018, Stellar surface magneto-convection as a source of astrophysical noise. II. Center-to-limb parameterization of absorption line profiles and comparison to observations, Astrophysical journal, vol. 866, no. 55, pp. 1-14, doi: 10.3847/1538-4357/aaddfc.

Attached Files
Name Description MIMEType Size Downloads

Title Stellar surface magneto-convection as a source of astrophysical noise. II. Center-to-limb parameterization of absorption line profiles and comparison to observations
Author(s) Cegla, HM
Watson, CA
Shelyag, SergiyORCID iD for Shelyag, Sergiy orcid.org/0000-0002-6436-9347
Chaplin, WJ
Davies, GR
Mathioudakis, M
Palumbo, ML
Saar, SH
Haywood, RD
Journal name Astrophysical journal
Volume number 866
Issue number 55
Start page 1
End page 14
Total pages 14
Publisher IOP Publishing
Place of publication Bristol, Eng.
Publication date 2018-10-10
ISSN 0004-637X
1538-4357
Keyword(s) profiles
planets and satellites
detection
stars
activity
low-mass
Sun
granulation techniques
radial velocities
science & technology
physical sciences
astronomy & astrophysics
Summary Manifestations of stellar activity (such as star-spots, plage/faculae, and convective flows) are well-known to induce spectroscopic signals often referred to as astrophysical noise by exoplanet hunters. For example, setting an ultimate goal of detecting true Earth analogs demands reaching radial velocity (RV) precisions of ∼9 cm s-1. While this is becoming technically feasible with the latest generation of highly stabilized spectrographs, it is astrophysical noise that sets the true fundamental barrier on attainable RV precisions. In this paper, we parameterize the impact of solar surface magneto-convection on absorption line profiles, and extend the analysis from the solar disk center (Paper I) to the solar limb. Off disk-center, the plasma flows orthogonal to the granule tops begin to lie along the line of sight, and those parallel to the granule tops are no longer completely aligned with the observer. Moreover, the granulation is corrugated and the granules can block other granules, as well as the intergranular lane components. Overall, the visible plasma flows and geometry of the corrugated surface significantly impact the resultant line profiles and induce center-to-limb variations in shape and net position. We detail these herein, and compare to various solar observations. We find our granulation parameterization can recreate realistic line profiles and induced radial velocity shifts, across the stellar disk, indicative of both those found in computationally heavy radiative 3D magnetohydrodynamical simulations and empirical solar observations.
Language eng
DOI 10.3847/1538-4357/aaddfc
Field of Research 0201 Astronomical And Space Sciences
0305 Organic Chemistry
0306 Physical Chemistry (Incl. Structural)
HERDC Research category C1.1 Refereed article in a scholarly journal
Copyright notice ©2018, The American Astronomical Society
Persistent URL http://hdl.handle.net/10536/DRO/DU:30114944

Document type: Journal Article
Collection: School of Information Technology
Connect to link resolver
 
Unless expressly stated otherwise, the copyright for items in DRO is owned by the author, with all rights reserved.

Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 0 times in TR Web of Science
Scopus Citation Count Cited 0 times in Scopus
Google Scholar Search Google Scholar
Access Statistics: 6 Abstract Views, 5 File Downloads  -  Detailed Statistics
Created: Thu, 15 Nov 2018, 13:53:31 EST

Every reasonable effort has been made to ensure that permission has been obtained for items included in DRO. If you believe that your rights have been infringed by this repository, please contact drosupport@deakin.edu.au.