Paola Marigo talks with
ScienceWatch.com and answers a few questions about
this month's New Hot Paper in the field of Space
Article Title: Evolution of asymptotic giant branch
stars - II. Optical to far-infrared isochrones with
improved TP-AGB models
P;Girardi, L;Bressan, A;Groenewegen, MAT;Silva,
Journal: ASTRON ASTROPHYS, Volume: 482, Issue: 3, Page:
883-905, Year: MAY 2008
* Univ Padua, Dipartimento Astron, Vicolo Osservatorio 2,
I-35122 Padua, Italy.
* Univ Padua, Dipartimento Astron, I-35122 Padua,
(addresses have been truncated)
Why do you think your paper is highly
There are two basic reasons. First, we provide theoretical photometric data
useful for the interpretation of a large variety of astronomical data.
Especially important is the inclusion of the mid-infrared spectral window,
which probes new physics and has become more widely accessible by new
satellites such as Spitzer and AKARI.
Second, our study is mainly focused on the so-called asymptotic giant
branch (AGB) phase, a fast stellar evolutionary phase, whose paramount
importance for the spectrophotometric and chemical evolution of galaxies
has only recently been recognized.
Does it describe a new discovery, methodology, or
synthesis of knowledge?
"Our models may help many other
astronomers to optimize the use of the
telescope time, hence leading to a more
rational exploitation of very expensive
The paper fits together the state-of-the-art knowledge of different
astrophysical fields, namely: theory of stellar evolution and
nucleosynthesis, mass loss in stars, dust formation, radiative transfer in
dusty environments, etc. Each co-author of the paper has effectively
contributed to this study, bringing individual expertise to bear in a
Would you summarize the significance of your paper
in layman's terms?
We supply other researchers with the capability of predicting the number
and luminosities of the stars that are expected to be observed in different
astrophysical environments—star clusters, near and far
galaxies—at any frequency interval of the electromagnetic spectrum,
ranging from the optical to the far-infrared. From directly comparing these
predictions with the data acquired through the telescopes, one can then
derive precious information about the history of these distant objects.
How did you become involved in this research, and
were there any problems along the way?
This line of research is the natural continuation of a long-term effort
aimed at providing reliable models for AGB stars, originally started during
my Ph.D. course carried out at the Department of Astronomy of the
University of Padua. The main problems I encountered along the way were the
small budgets allocated to the research, which in turn has implied limited
human resources to be actively involved in the work.
Where do you see your research leading in the
The follow-up of this research will be primarily directed to 1) improve the
modelling of the dust properties, including the nucleation of the grains
and their opacity characteristics; 2) predicting detailed chemical yields
from AGB stars, which are among the most important producers of the
chemical elements in the Universe, including our solar-system; 3) to
calibrate the fine details of our AGB stellar models on the basis of the
large stellar catalogs that are nowadays available for both the Milky Way
and external galaxies.
Do you foresee any social or political implications
for your research?
Our models may help many other astronomers to optimize the use of their
telescope time, hence leading to a more rational exploitation of very
Paola Marigo, Ph.D.
Dipartimento di Astronomia
Universita' di Padova
KEYWORDS: LARGE-MAGELLANIC-CLOUD; LONG-PERIOD VARIABLES;
MASS-LOSS RATES; POPULATION SYNTHESIS MODELS; SINGLE STELLAR
POPULATIONS; DUST CONDENSATION SEQUENCE; COLOR-MAGNITUDE DIAGRAMS;
SPITZER-SPACE-TELESCOPE; ACTIVE GALACTIC NUCLEI; DA WHITE-DWARFS.