[Alumnos] Charla de Profesora invitada: Margit Paparo (Hungria)

[Secretaria de Postgrado FCAG]

Invitación:

La Prof. Margit Paparo del MTA, CSFK, Konkoly Observatory Budapest 
(Hungary), brindará una charla titulada "CoRoT - Closer to the non-radial 
and non-linear effects of the pulsation". La misma tendrá lugar hoy 
jueves 27 de marzo a las 14:00 hs en el salón Meridiano.

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CoRoT - Closer to the non-radial and non-linear effects of the pulsation
Margit Paparo
MTA, CSFK, Konkoly Observatory
Budapest, Hungary

Abstract:

The space data basically changed the aspect of the variable star research. With 
the space projects (MOST, CoRoT, Kepler) we had good hope to solve some 
long-standing problems. The space data really increased our knowledge but 
created more and more questions that we have to solve. The Hungarian 
Asteroseismology Group (HAG) has a project working on CoRoT data supported by 
the European Space Agency (ESA). The group does not have a permenent team, it 
changes from time to time. The activity of HAG reflects the interest of the 
actual contributors from RR Lyrae to main sequence stars, from observational to 
theoretical approaches. I give a cross-section of the activity and results of 
HAG:

- The fine structure of the amplitude and phase modulation, the period doubling 
caused by 9:2 resonance are the newest results on the Blazhko type RR Lyrae 
stars (non-linear effects). Non-radial modes are clearly shown in these, 
traditionally pure radial pulsators (RRc). Using the formalizm of 
telecommunication for Blazhko type RR Lyrae stars presents a new theoretical 
approach to separate the physical processes as periodic, quasi-periodic, 
stohastic or chaotic.

- Light variations in colour channels were used to derive differential rotation 
in an active star and separate a Beta Ceph pulsation in a closely spaced star.

- Main sequence stars, both Delta Scuti and Gamma Doradus stars, pulsating in 
the non-asymptotic regime, suffer from the lack of mode identification. The 
increased number of excited modes and the lack of unlimited observing time for 
many targets inspire to find new approaches of the mode identification based 
only on the well-established observables, the frequency spacing and period 
ratios.

- We discovered the first CoRoT heart-beat binary, where the components 
have similar mass, similar abundances, slightly different temperature, 
however one of them shows Delta Scuti pulsation. In one binary system, we 
are faced with the long-standing question: why some of the stars pulsate 
in the instability strip but the others do not pulsate in the middle of 
the instability stip. We definitely need an advanced theoretical approach 
for answering the old/new questions.


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Dr. Alejandro H. Córsico
Secretario de Posgrado
Facultad de Ciencias Astronómicas y Geofísicas
Universidad Nacional de La Plata
http://www.fcaglp.unlp.edu.ar/area-docente/posgrado/posgrado
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