Broad-band linear polarization in late-type active dwarfs

نویسندگان
چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Optical Linear Polarization of Late M-and L-type Dwarfs

We report on the linear polarimetric observations in the Johnson I-band filter of 44 ultracool dwarfs with spectral types between M6 and L7.5, corresponding to effective temperatures in the range 2800–1400 K, and one M4.5-type star. Based on our measurements of polarization (P) and their associated error bars (σ P), eleven (10 L and 1 M) dwarfs appear to have significant linear polarization (P/...

متن کامل

Helium Lines in Late-type Dwarfs

We analyse the formation of He I lines in late-type dwarfs by statistical equilibrium (or NLTE radiative transfer) computations. Atmospheric models for dK (Eri) and dMe V1005Ori (=Gl 182) stars are considered. The validity of the weakly non-uniform approximation for dMe stars established in Lanzafame (1994a) for the lower transition region of dMe stars implies that streaming particles have virt...

متن کامل

Lithium depletion in late-type dwarfs

Using a self-consistent dynamic theory of non-local convection, the atmospheric lithiumabundance depletion values of a series of stellar evolutionary models withM = 0.725–1.5 M are calculated, and the results show that the general observed properties of lithium abundance in lower-main-sequence stars can be reproduced by overshooting mixing and gravitational settling. After a careful study of th...

متن کامل

Rotation and Activity in Late-type M Dwarfs

We have examined the relationship between rotation and activity in 14 late-type (M6M7) M dwarfs, using high resolution spectra taken at the Keck Observatory and flux-calibrated spectra from the Sloan Digital Sky Survey. Most are inactive at a spectral type where Hα emission has previously seen to be very common. We used the cross-correlation technique to quantify the rotational broadening; six ...

متن کامل

Spectral evidence for dust in late-type M dwarfs

We have found a dramatic change in the spectra of late-type M dwarfs at wavelengths shorter than 0.75μm. Comparisons with synthetic spectra illustrate that this change is well explained by the presence of dust. It thus seems that a substantial part of the long-standing discrepancies between late-type M dwarf models and observations arises from dust as recently proposed by Tsuji, Ohnaka & Aoki (...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Monthly Notices of the Royal Astronomical Society

سال: 2016

ISSN: 0035-8711,1365-2966

DOI: 10.1093/mnras/stw195