Powered by OpenAIRE graph
Found an issue? Give us feedback
image/svg+xml art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos Open Access logo, converted into svg, designed by PLoS. This version with transparent background. http://commons.wikimedia.org/wiki/File:Open_Access_logo_PLoS_white.svg art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos http://www.plos.org/ ZENODOarrow_drop_down
image/svg+xml art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos Open Access logo, converted into svg, designed by PLoS. This version with transparent background. http://commons.wikimedia.org/wiki/File:Open_Access_logo_PLoS_white.svg art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos http://www.plos.org/
ZENODO
Conference object . 2021
License: CC BY
Data sources: Datacite
image/svg+xml art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos Open Access logo, converted into svg, designed by PLoS. This version with transparent background. http://commons.wikimedia.org/wiki/File:Open_Access_logo_PLoS_white.svg art designer at PLoS, modified by Wikipedia users Nina, Beao, JakobVoss, and AnonMoos http://www.plos.org/
ZENODO
Conference object . 2021
License: CC BY
Data sources: Datacite
versions View all 2 versions
addClaim

Mapping stellar activity indicators across the M dwarf domain

Authors: Lafarga, Marina; Ribas, Ignasi; Reiners, Ansgar; Quirrenbach, Andreas; Amado, Pedro J.; Caballero, Jose A.; Azzaro, Marco; +15 Authors

Mapping stellar activity indicators across the M dwarf domain

Abstract

Despite stellar magnetic activity being present in most cool stars, its effects on spectroscopic observations are still not well understood. Several activity indicators are routinely used to identify activity-related signals in radial velocity (RV) measurements, but not all indicators trace exactly the same effects, nor are any of them always effective in all stars. This poses one of the main obstacles for the detection and characterisation of small exoplanets, as magnetic activity biases RV signals. In this work, we analyse the temporal behaviour of RVs and a set of spectroscopic indicators for 98 M dwarfs observed with CARMENES, with the aim of finding a relation between indicator performance and stellar properties. We find periodic signals related to activity for 56 sample stars. The activity indicators behave differently depending on the mass and activity level of the target star, e.g., cross-correlation function bisector inverse slope and chromatic index are effective activity tracers for the most active stars in the sample, especially stars with relatively high mass, while for less active stars, chromospheric lines perform best. Most of the targets for which we cannot identify any activity-related signal are stars at the low-mass end of the sample, where stars are fully convective, and also show the lowest RV scatter. This could potentially hint at different manifestations of activity compared to higher-mass stars. Moreover, ultracool M dwarfs could be better candidates for planet searches than earlier types, which display higher levels of RV variability. Our results show that none of the indicators are effective activity tracers for all stars. Therefore, an analysis of a large set of indicators seems necessary to obtain a complete picture of stellar activity variability. This becomes critical when assessing the origin of RV signals, as not using the most effective indicators considering the characteristics of the star may lead to false planet claims.

Keywords

low-mass stars, stellar activity, Cool Stars on the main sequence, late-type stars, radial velocities, rotation

  • BIP!
    Impact byBIP!
    selected citations
    These citations are derived from selected sources.
    This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    0
    popularity
    This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
    Average
    influence
    This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    Average
    impulse
    This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
    Average
    OpenAIRE UsageCounts
    Usage byUsageCounts
    visibility views 11
    download downloads 12
  • 11
    views
    12
    downloads
    Powered byOpenAIRE UsageCounts
Powered by OpenAIRE graph
Found an issue? Give us feedback
visibility
download
selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
views
OpenAIRE UsageCountsViews provided by UsageCounts
downloads
OpenAIRE UsageCountsDownloads provided by UsageCounts
0
Average
Average
Average
11
12
Green
Related to Research communities
STARS EU