Published February 26, 2021 | Version v1
Poster Open

Spectropolarimetry in optical and near-IR for EV Lac and AD Leo: what is stellar activity's favourite colour?

  • 1. IRAP
  • 2. LUPM
  • 3. ESA/ESTEC

Description

Stellar activity hinders the detection of small exoplanets with the radial velocity (RV) method, because it introduces spurious signals that can drown or mimic planetary signatures. It is therefore crucial to understand and filter out activity signals, especially in light of future small planet searches.

We investigate ways to reduce activity jitter in RV time series using spectropolarimetric data sets in optical (ESPaDOnS@CHFT and NARVAL@TBL), and in near-infrared (nIR) with SPIRou@CHFT. We employ two approaches: 1) perform a chromatic study of typical stellar activity proxies, and  2) study a parametric selection of spectral lines to build a mask for Least-Square Deconvolution. The study is performed for EV Lac and AD Leo, two very active M dwarfs.

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References

  • Queloz et al. 2001, A&A, 379, 279-287
  • Huelamo et al. 2008, A&A, 2, L9-L13
  • Donati et al. 1997, MNRAS, 291, 658
  • Boisse et al. 2009, A&A, 495, 959-966
  • Donati et al. 2016, Nature, 7609, 662-666
  • Hebrard et al. 2016, MNRAS, 461, 1465-1497
  • Haywood et al. 2014, MNRAS, 443, 2517-2531
  • Zechmeister & Kürster 2009, A&A, 496, 577-584