Letters of Intent received in 2021

LoI 2023-2156
Stellar Rotation - The Portrait Revealed by Space Missions and Ground Based Surveys

Topics

- OBSERVATIONS OF ROTATING STARS: THE ROYAL ROUTE FROM SPACE MISSIONS AND LARGE GROUND BASED SURVEYS
- THE SUN ROTATION
- ROTATION: SOLAR AND STELLAR PHYSICS
- ROTATION, MAGNETIC FIELDS AND CHEMICAL ABUNDANCES
- ROTATION CONTROLLING THE STAR LIFE
- IMPACT OF ROTATION FOR THE EXOPLANETOLOGY
- MODELING ROTATING STARS
- THE EVOLUTION OF ROTATING STARS
- FINAL STAGES AND NUCLEOSYNTHESIS

Rationale

Rotation is a fundamental observable in stellar astrophysics, driving strongly the life of stars, providing important constraints for models of angular momentum evolution and valuable information on the behavior of different stellar properties, including magnetic activity, chemical abundances and multiplicity. In spite of such a fundamental role, its development is rather slow. For instance, most of our knowledge on the behavior of stellar rotation, prior to 2000, comes from pioneering works carried out along the 2nd half of the past century. Of course, only projected rotational velocity could be measured by these previous studies, but there are strong evidences that this parameter is largely governed by the efficiency of the transport of angular momentum inside the stars. From Otto Struve, S. Huang and colleagues to M. Mayor and co-workers, we find now in the literature measurements of projected rotational velocity for thousands of stars, composing homogeneous samples in different regions of the HR Diagram. From these data emerged important relationships between rotation and metallicity, abundance anomalies, chromospheric and coronal activity, tidal interaction in close binaries, as well as solid constraints for modeling rotating stars, in addition to a portrait of the distribution of rotation and its dependence on stellar age.

The advent of space missions like CoRoT, Kepler and GAIA, and more recently TESS, seems to bring new brushes and paints for drawing an even more complete portrait of stellar rotation. From 2006 to date, tens of thousands of rotation periods were produced by different teams, including J. R. De Medeiros and co-workers at Federal University of Rio Grande do Norte in Natal, T. Mazeh and colleagues at Tel Aviv University, G. Basri at California University, Berkeley, T. Reinhold and colleagues at Max-Planck-Institut für Sonnensystemforschung, T. Ceillier at the University of Paris-Saclay, M. B. Nielsen at Birmingham University, J. R. A. Davenport at Western Washington University and L. Balona at South African Astronomical Observatory. These missions are also revealing the mysteries of the stellar interiors based on studies of differential rotation and asteroseismology as, for example, those conducted by T. Reinhold and co-workers, at Max-Planck-Institut für Sonnensystemforschung, and C. Aerts and colleagues at the Instituut voor Sterrenkunde at Leuven, respectively.

In view of this new picture, it seems a good time for an IAU Symposium dedicated to Stellar Rotation, to discuss in large and in depth the revolutionary data emerging from the referred space missions, including a more detailed comparison between observations and theory. It is also mandatory to discuss strategies for an enlarged and optimal investigation of that fabulous data basis legacy. Of course, it urges to discuss also what is not yet revealed by the present-day observations, as well as its impact for our current understanding of the Physics of stars, the Sun and planetary systems. Let us underline that in the last 50 years there have been only two IAU meetings fully dedicated to Stellar Rotation: the IAU colloquium 4, held at the Ohio State University, at Columbus, in 1969, and the IAU Symposium 215, held at Cancún, in 2002.

Remark: Coordinating Division and Supporting Divisions will still be confirmed