Hα LINE AS AN INDICATOR OF ENVELOPE PRESENCE AROUND THE CEPHEID POLARIS Aa (α UM i)
Journal Title: Odessa Astronomical Publications - Year 2015, Vol 28, Issue 1
Abstract
We present the results of the radial velocity (RV ) measurements of metallic lines as well as Hα (Hβ ) obtained in 55 high-resolution spectra of the Cepheid α UMi (Polaris Aa) in 1994–2010. While the RV amplitudes of these lines are roughly equal, their mean RV begin to differ essentially with growth of the Polaris Aa pulsational activity. This difference is accompanied by the Hα core asymmetries on the red side mainly (so-called knifelike profiles) and reaches the value of 8–12 km/s in 2003 with subsequent decrease to 1.5–2 km/s. We interpret so unusual behaviour of the Hα line core as dynamical changes in the envelope around Polaris Aa.
Authors and Affiliations
I. A. Usenko, A. S. Miroshnichenko, V. G. Klochkova, N. S. Tavolzhanskaya
Keywords
Related Articles
- EP ID EP604453
- DOI -
- Views 82
- Downloads 0
THE CHANGING LOOK AGNS MONITORING PROJECT
The Changing Look AGNs (CL AGNs) are objects which undergo dramatic variability of the emission line profiles and classification type of which can move from one spectral class to another within very short time interval (...
SECULAR DECREASE THE FLUX OF SUPERNOVA REMNANT CAS A ON MONITORING RESULTS TO RADIOTELESCOPE "URAN-4" IRA NASU
This work is dedicated to the study of secular decrease of the flux of young supernova remnant Cas A according to observations by radio- telescope "URAN-4» of Odessa Observatory IRA NASU from 1987 to 2001 years on freque...
2-field model of dark energy with canonical and non-canonical kinetic terms
For some parametrizations of the dark energy equation of state that varies in time there is transition from quintessence to phantom or vice versa at a certain redshift. Quintom – the 2-field model with 2 canonical kineti...
ACCURACY OF SATELLITE OPTICAL OBSERVATIONS AND PRECISE ORBIT DETERMINATION
The monitoring of low-orbit space objects (LEO-objects) is performed in the Astronomical Observatory of Odessa I.I. Mechnikov National University (Ukraine) for many years. Decades-long arсhives of these observa...
CREATION OF LARGE CATALOGUES BY USING OF VIRTUAL OBSERVATORIES
We developed an application program to search images in the registers and databases of Virtual Observatories and to download them to local computer. The program has the ability to process XML file in VO Table format to g...