Search Publications
Review of Hinode results
Suematsu, Y.
Hinode is an observatory-style satellite, carrying three advanced instruments being designed and built to work together to explore the physical coupling between the photosphere and the upper layers for understanding the mechanism of dynamics and heating. The three instruments aboard are the Solar Optical Telescope (SOT), which can provide high-pre…
Advances in solar rotation rate inferences: Unstructured grid inversions and improved rotational splittings
Eff-Darwich, A.; Korzennik, S. G.; García, R. A.
We present a new inversion methodology that adapts the inversion grid in both radius and co-latitude to the data set and solves the inversion problem through an iterative procedure. This method was tested on state-of-the-art global mode frequency splittings to assess the solar interior rotation rate and its temporal variation. We also explore the …
SSS in young stellar populations and the ``prompt" component of Type Ia supernovae
Nelson, T.; Orio, M.; Di Mille, F.
We present the results of a search for UV and optical counterparts of the SSS population in M 31. We find that out of the 56 sources we included in our search, 16 are associated with regions of ongoing or recent star formation. We discuss two particularly interesting sources that are identified optically as early type stars, one of which displayed…
The acoustic and magnetic solar cycle
Komm, R.
The frequency variation of global modes provides information about the solar structure and the rotation rate of the solar interior. The solar-cycle variation of the rotation rate, the so-called torsional oscillation, extends throughout the convection zone. Alternating bands of faster- and slower-than-average rotation move from mid-latitudes toward…
Probability distribution functions for the Sun's magnetic field
Stenflo, J. O.
Magnetoconvection structures the Sun's magnetic field cover a vast range of scales, down to the magnetic diffusion scale that is orders of magnitude smaller than the resolution of current telescopes. The statistical properties of this structuring are governed by probability density functions (PDFs) for the flux densities and by the angular distrib…
Observational results from active region seismology
González Hernández, I.
Active regions are one of the most observed features in the solar surface. High-resolution solar telescopes on ground and space have revealed the fine configuration of umbra and penumbra of sunspots with amazing detail. However, the subsurface structure of sunspots and active regions remains, for the most part, unknown. Thanks to the development o…
X-ray emission from GPS and CSS sources
Siemiginowska, A.
Many X-ray observations of GigaHertz Peaked Spectrum and Compact Steep Spectrum sources have been made with Chandra X-ray Observatory and XMM-Newton Observatory over the last few years. The X-ray spectra contribute the important information to the total energy distribution of the compact radio sources. In addition the spatial resolution of Chandra…
Parameters of the components of visually close binary systems: Hip 11352
Al-Wardat, M. A.
Model atmospheres of the components of the visually close binary system Hip 11352 were constructed using a grid of Kurucz's blanketed models. The entire observational spectral energy distribution of the system was used as a reference for the comparison with synthetic ones created from the model atmospheres. The parameters of the components of the …
New absolute magnitude calibrations for W Ursa Majoris type binaries
Demircan, O.; Eker, Z.; Bilir, S. +2 more
Parallaxes of W UMa stars in the Hipparcos catalogue have been analyzed. 31 W UMa stars, which have the most accurate parallaxes (σπ/π<0.15) which are neither associated with a photometric tertiary nor with evidence of a visual companion, were selected for re-calibrating the Period-Luminosity-Color (PLC) relation of W UMa stars. Usin…
The evolution of cluster early-type galaxies over the past 8 Gyr
Fritz, A.; Jørgensen, I.; Schiavon, R. P. +1 more
We present the Fundamental Plane (FP) of early-type galaxies in the clusters of galaxies RXJ1415.1+3612 at z=1.013. This is the first detailed FP investigation of cluster early-type galaxies at redshift z=1. The distant cluster galaxies follow a steeper FP relation compared to the local FP. The change in the slope of the FP can be interpreted as a…