Miguel Roth
Miguel Roth has directed Carnegie’s Las Campanas Observatory, in Chile, since 1990. During his tenure, both 6.5-meter Magellan telescopes were constructed and became operational. In addition to his growing administrative responsibilities, Roth remains active in his research on star formation, as a participant in the Carnegie Supernova Project, and in maintaining infrared instrumentation.
Roth has fruitful collaborations with groups in Italy and Mexico in two extremely different areas of star formation research: massive star formation in giant molecular clouds, and the search for the lowest mass stars known as brown dwarfs in nearby regions of our Galaxy. Roth’s goal is to determine if extremely low-mass stars form in the same way as slightly more massive stars that have clear thermonuclear activity. Characteristically, early stages of low-mass star formation are indicated by the presence of gas outflows, generally bipolar, related to the adjustment of the newly formed stars, their excess mass and angular momentum. These outflows interact with the circumstellar medium producing shock-excited regions. The hydrogen molecule is one of the best tracers of such interactions. The researchers are looking for these outflows by imaging the neighborhood of brown dwarfs at wavelengths corresponding to molecular hydrogen that has been excited by shocks. Although shock-excited H2 in the areas surveyed areas has not been found, he expects to continue along this line.
Two of the most compelling problems in astronomy today are to identify the nature and behavior of dark matter and dark energy. Astronomers have discovered that only a small fraction of matter in universe is luminous. Most is dark matter, undetectable by standard means. Recently, researchers have also found that there is a pervasive repulsive force—dark energy—that is causing the universe to expand at an accelerating rate. By studying the light from Type Ia and II supernovae one can gauge the distance to the objects’ host galaxies and the rate at which the universe is expanding. Researchers including Roth are trying to understand dark matter and dark energy by studying supernovae through the efforts of the Carnegie Supernova Project (CSP).
Carnegie and visiting astronomers use a variety of instruments at Las Campanas. Roth also helps maintain the infrared instrumentation on all of the Observatories’ telescopes and supports astronomers using these tools.
