Non periodic ordered sequences obtained by production rules in formal grammars are applied to the analysis of the multi-periodicity of the δ-Scuti type variabl
<正>Starting from a dipole field and a given distribution of footpoint displace- ment of field lines on the photosphere,we find axisymmetric,force-free field so
We collected the basic parameters of 231 supernova remnants (SNRs) in our Galaxy, namely, distances (d) from the Sun, linear diameters (D), Galactic heights (Z)
Using Nancay Radioheliograph (NRH) imaging observations, combined with SOHO/Michelson Doppler Imager (MDI) magnetogram observations and coronal magnetic field
Recent analysis of the long term radio light curve of the extremely variable BL Lacertae object AO 0235t16 by Raiteri et al. have revealed the presence of recur