2019MNRAS.484.2674R


Query : 2019MNRAS.484.2674R

2019MNRAS.484.2674R - Mon. Not. R. Astron. Soc., 484, 2674-2683 (2019/April-1)

A discontinuity in the Teff-radius relation of M-dwarfs.

RABUS M., LACHAUME R., JORDAN A., BRAHM R., BOYAJIAN T., VON BRAUN K., ESPINOZA N., BERGER J.-P., LE BOUQUIN J.-B. and ABSIL O.

Abstract (from CDS):

We report on 13 new high-precision measurements of stellar diameters for low-mass dwarfs obtained by means of near-infrared long-baseline interferometry with PIONIER at the Very Large Telescope Interferometer. Together with accurate parallaxes from Gaia DR2, these measurements provide precise estimates for their linear radii, effective temperatures, masses, and luminosities. This allows us to refine the effective temperature scale, in particular towards the coolest M-dwarfs. We measure for late-type stars with enhanced metallicity slightly inflated radii, whereas for stars with decreased metallicity we measure smaller radii. We further show that Gaia DR2 effective temperatures for M-dwarfs are underestimated by ∼8.2 per cent and give an empirical MG-Teff relation that is better suited for M-dwarfs with Teff between 2600 and 4000 K. Most importantly, we are able to observationally identify a discontinuity in the Teff-radius plane, which is likely due to the transition from partially convective M-dwarfs to the fully convective regime. We found this transition to happen between 3200 and 3340 K, or equivalently for stars with masses ~0.23 M. We find that in this transition region the stellar radii are in the range from 0.18 to 0.42 R for similar stellar effective temperatures.

Abstract Copyright: © 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): techniques: interferometric - stars: fundamental parameters - stars: late-type - stars: low-mass

Simbad objects: 22

goto Full paper

goto View the references in ADS

Number of rows : 22
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2022
#notes
1 HD 225213 Er* 00 05 24.4284351777 -37 21 26.507931505 11.074 10.022 8.562 7.589 6.432 M2V 194 0
2 HD 285968 PM* 04 42 55.7750207949 +18 57 29.395947044 12.668 11.49 9.951 8.931 7.702 M2.5V 296 2
3 HD 36395 PM* 05 31 27.3957852161 -03 40 38.024004501 10.626 9.443 7.968 6.996 5.913 M1.5Ve 474 0
4 BD+05 1668 PM* 07 27 24.4989685603 +05 13 32.841491057 12.558 11.443 9.872 8.699 7.161 M3.5V 376 0
5 Wolf 359 Er* 10 56 28.9208702274 +07 00 53.003285286 16.706 15.541 13.507 11.684 9.507 dM6 676 0
6 HD 95735 Er* 11 03 20.1948195942 +35 58 11.576182057 10.030 8.960 7.520 5.99 4.79 M2+V 671 0
7 Ross 905 PM* 11 42 11.0933350978 +26 42 23.650782778   12.06 10.613 10.272 8.24 M3V 569 1
8 Ross 128 Er* 11 47 44.3972681420 +00 48 16.400337591 14.223 12.905 11.153 9.859 8.184 dM4 379 0
9 HD 119850 Er* 13 45 43.7755597223 +14 53 29.471707437 10.989 9.894 8.50 7.465 6.363 M2V 321 0
10 NAME Proxima Centauri Er* 14 29 42.9461331854 -62 40 46.164680672 14.21 12.95 11.13 9.45 7.41 M5.5Ve 1137 0
11 BD-07 4003 BY* 15 19 26.8269387505 -07 43 20.189497466 13.403 11.76 10.560 9.461 8.911 M3V 589 2
12 BD-12 4523 BY* 16 30 18.0583947383 -12 39 45.321217732 12.829 11.638 10.072 8.917 7.421 M3V 286 0
13 BD+25 3173 PM* 16 58 08.8496107083 +25 44 38.974052855 12.342 11.139 9.655 8.685 7.602 M2V 197 1
14 CD-46 11540 LM* 17 28 39.9455781571 -46 53 42.688095874 12.177 10.973 9.407 8.337 7.006 M3V 229 1
15 BD+68 946 PM* 17 36 25.8993094605 +68 20 20.909627174 11.73 10.65   8.3   M3.0V 271 0
16 NAME Barnard's star BY* 17 57 48.4984700685 +04 41 36.113879676 12.497 11.24 9.511 8.298 6.741 M4V 743 2
17 Ross 154 Er* 18 49 49.3637762005 -23 50 10.447375350 13.528 12.19 10.43 10.23 7.703 M3.5Ve 353 0
18 HD 199305 PM* 20 53 19.7889212813 +62 09 15.817261385   10.459   7.7   M1.0V 205 0
19 HD 204961 PM* 21 33 33.9751191976 -49 00 32.399427028 11.359 10.176 8.672 7.665 6.479 M2/3V 245 1
20 BD-15 6290 BY* 22 53 16.7325836486 -14 15 49.304052185 12.928 11.749 10.192 9.013 7.462 M3.5V 925 1
21 HD 216899 PM* 22 56 34.8046530863 +16 33 12.355636588 11.323 10.143 8.638 7.657 6.542 M1.5V 264 0
22 HD 217987 PM* 23 05 52.0357857091 -35 51 11.055185039   8.83 7.39     M2V 244 0

To bookmark this query, right click on this link: simbad:objects in 2019MNRAS.484.2674R and select 'bookmark this link' or equivalent in the popup menu


2022.07.06-08:39:30

© Université de Strasbourg/CNRS

    • Contact