Research Interests
The role of mass loss, especially episodic mass loss, in evolved massive stars is one of the outstanding questions in stellar evolution theory. I am studying the evolutionary stages of a representative sample of evolved massive stars, their stellar variabilities and instabilities, and the history and nature of their mass-loss episodes.
Topics
Stellar spectroscopy, stellar winds, nebular physics, late stages of massive star evolution (luminous blue variables, yellow hypergiants, red and blue supergiants), variable massive stars, supernova impostors, supernova progenitors.
Objectives
Determination of the evolutionary stages of evolved massive stars, their stellar variabilities and instabilities, and the history and nature of their mass-loss episodes.
Methods
Ultra-violet to near-infrared spectra, photometry, and interferometry. The stellar variabilities, large-scale morphologies, small-scale structures, velocities, kinematic ages, current mass-loss geometries, abundances, electronic densities, ionization fractions, and temperatures are studied.
- Work Experience
- Education
- Publications
Professional Experience
05/2015 - PRESENT Staff Astronomer, European Southern Observatory, Santiago, Chile
09/2011 - 04/2015 Postdoctoral Research Fellow, European Southern Observatory, Santiago, Chile
01/2008 - 06/2011 Research Assistant, University of Minnesota, Twin Cities, USA
08/2007 - 12/2008 Teaching Assistant, University of Minnesota, Twin Cities, USA
04/2003 - 03/2004 Teaching Assistant, Friedrich Schiller University, Jena, Germany
07/2002 - 01/2003 Paid Internship, Fraunhofer IOF (Institute of Applied Optics and Precision Engineering), Jena, Germany
07/2004 - 08/2004 Internship, Friedrich Schiller University, Jena, Germany
Education
08/2007 - 06/2011 Ph.D. in Astrophysics, University of Minnesota, Twin Cities, MN, USA
Advisor: Prof. Kris Davidson
PhD Thesis: Exploring and Modeling High-excitation Emission in the Ejecta and the Wind of Eta Carinae
10/2001 - 07/2007 Diploma in Physics (equiv. to Master of Science M.Sc.), Friedrich-Schiller University, Jena, Germany
Advisor: Dr. Eike Guenther
Diploma Thesis: Spectroscopic Analysis of Brown Dwarfs
09/2004 - 06/2005 University of Granada, Granada, Spain
Publications
Summary: refereed articles = 34 (12 as first author since 2008), total number of citing papers = 824 (111 for first author contributions), h-index = 15
I started in September 2011 as a Postdoctoral Research Fellow at the European Southern Observatory, Santiago, Chile. Since May 2015, I am a staff member, supporting UT2 and UT3. I am instrument scientist for X-hooter and also part of the instrument team of ESPRESSO. I am the project scientist for the observation preparation tool GuideCam.
Contact
Av. Alonso de Cordova 3107
Vitacura, Santiago, Chile
Email: amehner(at)eso(dot)org
Phone: +56 2 24633068