Can the lack of red giants near the galactic center be explained by higher past galactic jet activity?

KURFÜRST, Petr. Can the lack of red giants near the galactic center be explained by higher past galactic jet activity? In AAS High Energy Astrophysics Division meeting #21, id. 102.13. Bulletin of the American Astronomical Society. 2024. ISSN 2330-9458.

Základní údaje

Originální název

Can the lack of red giants near the galactic center be explained by higher past galactic jet activity?

Autoři

KURFÜRST, Petr

Vydání

AAS High Energy Astrophysics Division meeting #21, id. 102.13. Bulletin of the American Astronomical Society, 2024

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Další údaje

Jazyk

angličtina

Typ výsledku

Konferenční abstrakt

Obor

10308 Astronomy

Stát vydavatele

Spojené státy

Utajení

není předmětem státního či obchodního tajemství

Označené pro přenos do RIV

Ne

Organizační jednotka

Přírodovědecká fakulta

ISSN

Klíčová slova anglicky

jet-star interaction; galactic center; red giant stars

Příznaky

Mezinárodní význam

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Anotace

V originále

For a long time, the scientific community has been theorizing and debating about the missing red giants near the center of our galaxy. About three to four years ago, a new theory, supported by analytical calculations, was proposed, based on the idea of the long-term ablation of the outer layers of red giants during a large number of repeated passages through a relativistic galactic jet. We are currently completing work on detailed numerical modeling of this phenomenon. We are using both our own advanced multidimensional hydrodynamical code and the widely used and tested CASTRO code for the calculations. We determine the initial state of the star, i.e. its density, pressure, and temperature profile, as a polytropic model. We then investigate the rate of ablation of the surface layers of the red giant star as it passes through the Galactic jet at different distances from the Galactic center. Subsequently, we also take into account the hydrodynamic relaxation of the star in the period between the passages through the jet. These changes, especially if we consider a larger number of stars from a dense nuclear star cluster undergoing a similar evolution, may contribute to the visible changes in observable characteristics in this region. These processes may also play a role in the acceleration of particles in shock waves, as a possible source of cosmic rays, etc.