2018A&A...614A.122T


C.D.S. - SIMBAD4 rel 1.7 - 2020.09.19CEST06:05:52

2018A&A...614A.122T - Astronomy and Astrophysics, volume 614A, 122-122 (2018/6-1)

The CARMENES search for exoplanets around M dwarfs. Radial-velocity variations of active stars in visual-channel spectra.

TAL-OR L., ZECHMEISTER M., REINERS A., JEFFERS S.V., SCHOFER P., QUIRRENBACH A., AMADO P.J., RIBAS I., CABALLERO J.A., ACEITUNO J., BAUER F.F., BEJAR V.J.S., CZESLA S., DREIZLER S., FUHRMEISTER B., HATZES A.P., JOHNSON E.N., KURSTER M., LAFARGA M., MONTES D., MORALES J.C., REFFERT S., SADEGI S., SEIFERT W. and SHULYAK D.

Abstract (from CDS):


Context. Previous simulations predicted the activity-induced radial-velocity (RV) variations of M dwarfs to range from ∼1 cm s–1 to ∼1 km s–1, depending on various stellar and activity parameters.
Aims. We investigate the observed relations between RVs, stellar activity, and stellar parameters of M dwarfs by analyzing CARMENES high-resolution visual-channel spectra (0.5-1µm), which were taken within the CARMENES RV planet survey during its first 20 months of operation.
Methods. During this time, 287 of the CARMENES-sample stars were observed at least five times. From each spectrum we derived a relative RV and a measure of chromospheric Hα emission. In addition, we estimated the chromatic index (CRX) of each spectrum, which is a measure of the RV wavelength dependence.
Results. Despite having a median number of only 11 measurements per star, we show that the RV variations of the stars with RV scatter of >10 m s–1 and a projected rotation velocity v sin i > 2 km s–1 are caused mainly by activity. We name these stars "active RV-loud stars" and find their occurrence to increase with spectral type: from ∼3% for early-type M dwarfs (M0.0-2.5 V) through ∼30% for mid-type M dwarfs (M3.0-5.5 V) to >50% for late-type M dwarfs (M6.0-9.0 V). Their RV-scatter amplitude is found to be correlated mainly with v sin i. For about half of the stars, we also find a linear RV-CRX anticorrelation, which indicates that their activity-induced RV scatter is lower at longer wavelengths. For most of them we can exclude a linear correlation between RV and Hα emission.
Conclusions. Our results are in agreement with simulated activity-induced RV variations in M dwarfs. The RV variations of most active RV-loud M dwarfs are likely to be caused by dark spots on their surfaces, which move in and out of view as the stars rotate.

Abstract Copyright: © ESO 2018

Journal keyword(s): stars: late-type - stars: activity - stars: rotation - techniques: radial velocities

VizieR on-line data: <Available at CDS (J/A+A/614/A122): stars.dat table.dat>

Simbad objects: 35

goto Full paper

goto View the reference in ADS

Number of rows : 35

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 Wolf 47 Er* 01 03 19.8342607685 +62 21 55.831198996   15.34   12.4   M5V 164 0
2 Barta 161 12 SB* 01 35 13.9238924192 -07 12 51.455163714   14.93 13.43 13.053 10.52 M4.3V 52 0
3 G 173-39 Fl* 02 08 53.6242116101 +49 26 56.440779580   14.01   12.118   M4.0V 52 0
4 G 80-21 PM* 03 47 23.3412010775 -01 58 19.945342289 14.052 13.048 11.537 10.452 9.098 M3.0V 82 0
5 UCAC4 554-010638 Er* 04 47 12.2486047573 +20 38 10.799382900   16.0 14.216 13.988   M5.0V 22 0
6 V* V2689 Ori RS* 05 36 30.9904303980 +11 19 40.331999226 11.508 10.276 8.898 7.963 7.140 K6V 112 0
7 G 99-49 Fl* 06 00 03.5038608130 +02 42 23.596778811   13.01 11.31 10.04 8.43 M3.5Ve 102 0
8 V* YZ CMi Er* 07 44 40.1726285952 +03 33 08.877830321 13.761 12.831 11.225 9.958 8.263 M4.0Ve 783 0
9 G 51-15 Er* 08 29 49.3528237575 +26 46 33.626773321   16.87   14.736   M6.5Ve 254 0
10 G 161-71 PM* 09 44 54.1925131725 -12 20 54.374177667   15.47 13.646 13.467 10.353 M5.0V 42 0
11 Wolf 359 Er* 10 56 28.826208 +07 00 52.34400 16.706 15.541 13.507 11.684 9.507 M6Ve 633 0
12 StKM 2-809 PM* 12 15 39.3673552228 +52 39 08.720024785     12.564 12.197   M4.0V 23 0
13 V* GL Vir Er* 12 18 59.3999178645 +11 07 33.770248089   15.68 13.90 13.55   M4.5Ve 138 0
14 FBS 1415+456 PM* 14 17 22.1023718376 +45 25 45.996305049   15.73 14.21 13.93   M5/6 15 0
15 V* V645 Cen Er* 14 29 42.9451234609 -62 40 46.170818907 14.21 12.95 11.13 9.45 7.41 M5.5Ve 973 0
16 V* OT Ser Ro* 15 21 52.9325996324 +20 58 39.910979308 12.662 11.522 10.003 8.993 7.843 M1.0V 106 0
17 G 256-25 PM* 15 49 55.1562345162 +79 39 51.645141756   16.3   14.408   M5.0V 19 0
18 G 180-60 Fl* 16 31 18.7890545317 +40 51 51.704950897   16.5   14.550   M6V 47 0
19 VB 8 Fl* 16 55 35.2561420232 -08 23 40.752903617   18.7 16.916 14.566 12.24 M7Ve 381 0
20 G 19-7 Fl* 16 57 05.7363418748 -04 20 56.317527343   13.92 12.25 10.99 9.432 M3.5Ve 76 0
21 CD-46 11540 PM* 17 28 39.9455601300 -46 53 42.693246243 12.177 10.973 9.407 8.337 7.006 M3V 206 1
22 LSPM J1733+1655 BY* 17 33 53.1638454477 +16 55 12.835817374   16.13 14.38 14.04 10.896 M6V 28 0
23 NAME Barnard's star BY* 17 57 48.4997994034 +04 41 36.111354228 12.497 11.24 9.511 8.298 6.741 M4V 660 2
24 G 227-22 PM* 18 02 16.6046894780 +64 15 44.238912144   14.74   13.010   M5.0V 52 0
25 G 258-33 Fl* 18 18 57.2324145507 +66 11 33.301424583   15.29   13.096   M4.5V 69 0
26 2MASSI J1835379+325954 PM* 18 35 37.8803560459 +32 59 53.311357837   20.0   17.1   M8.5V 101 0
27 Ross 154 Er* 18 49 49.3638007809 -23 50 10.453568573 13.528 12.19 10.43 10.23 7.703 M3.5Ve 323 0
28 VB 10 Er* 19 16 57.6103282334 +05 09 01.588675251     17.30     M8V 435 1
29 2MASS J19253089+0938235 PM* 19 25 30.9105593924 +09 38 23.293955612   19.2   16.7   M8/9V 15 0
30 G 208-42 Fl* 19 51 09.3205269987 +46 29 00.208931632   14.47   12.544   M4.0V 109 0
31 UCAC4 444-118477 PM* 20 09 18.2473320307 -01 13 38.317187107     14.47 12.98 11.16 M5.0V 19 0
32 V* V374 Peg Er* 22 01 13.1233106147 +28 18 24.913041858       11.602   M3.5Ve 168 0
33 V* EV Lac Er* 22 46 49.7311740821 +44 20 02.372223230   11.85 10.26 9.89   M4.0V 803 2
34 V* GT Peg BY* 22 51 53.5351541240 +31 45 15.195567260       11.281   M3.5V 135 0
35 RX J2354.8+3831 PM* 23 54 51.4574111640 +38 31 36.200571993   14.78   12.94   M3.1V 31 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2018A&A...614A.122T and select 'bookmark this link' or equivalent in the popup menu


2020.09.19-06:05:52

© Université de Strasbourg/CNRS

    • Contact