Related papers: Observational constraints to boxy/peanut bulge for…
The Galactic Bulge can uniquely be studied from large samples of individual stars, and is therefore of prime importance for understanding the stellar population structure of bulges in general. Here the observational evidence on the…
Recent observations have discovered the presence of a Box/Peanut or X-shape structure in the Galactic bulge. Such Box/Peanut structures are common in external disc galaxies, and are well-known in N-body simulations where they form following…
In some scenarios for the formation of the Milky Way bulge the stellar population at the edges of the boxy bulge may be younger than those on the minor axis, or close to the Galactic center. So far the only bulge region where deep…
We have obtained long-slit spectroscopy for a sample of 20 early-type barred galaxies to study the influence of bars in the building of galaxy bulges. Line strength indices were measured and used to derive age and metallicity gradients in…
The question whether stellar bars are either transitory features or long-lived structures is still matter of debate. This problem is more acute for double-barred systems where even the formation of the inner bar remains a challenge for…
The structure and evolution of the stellar velocity ellipsoid plays an important role in shaping galaxies undergoing bar driven secular evolution and the eventual formation of a boxy/peanut bulge such as present in the Milky Way. Using…
(Abridged) Star-forming nuclear rings in barred galaxies are common in nearby spirals, and their detailed study can lead to important insights into the evolution of galaxies, their bars, and their central regions. We present integral field…
The bar structure in disk galaxies models is formed by different families of orbits; however, it is not clear how these families of orbits support the bar throughout its secular evolution. Here, we analyze the orbital structure on three…
Many barred galaxies, possibly including the Milky Way, have cusps in the centres. There is a widespread belief, however, that usual bar instability taking place in bulgeless galaxy models is impossible for the cuspy models, because of the…
We have measured the radial light profiles and global shapes of bars using two-dimensional 3.6 $\mu m $ image decompositions for 144 face-on barred galaxies from the Spitzer Survey of Stellar Structure in Galaxies (S4G). The bar surface…
It is well established that bars evolve significantly after they form in galaxy discs, often changing shape both in and out of the disc plane. In some cases they may bend or buckle out of the disc plane resulting in the formation of…
From the decades of the theoretical studies, it is well known that the formation of the bar triggers the gas funnelling into the central sub-kpc region and leads to the formation of a kinematically cold nuclear stellar disc (NSD). We…
By using $N$-body and hydro simulations, we study the formation and evolution of bars in galaxies with significant gas content focusing on the phenomenon of the buckling instability. The galaxies are initially composed of a spherical dark…
We report about the fact that the stellar population that is born in the gas inflowing towards the central regions can be vertically unstable leading to a B/PS feature remarkably bluer that the surrounding bulge. Using new chemodynamical…
We study vertical resonant trapping and resonant heating of orbits. These two processes both lead to the growth of a boxy/peanut-shaped bulge in a typical $N$-body model. For the first time, we study this by means of the action variables…
A map of the projected density of the old stellar population of the Galactic Bulge region is reconstructed using 2MASS data. By making a combination of the H and K photometric bands, it is possible to overcome the effect of reddening, and…
Over half of disk galaxies are barred, yet the mechanisms for bar formation and the life-time of bar buckling remain poorly understood. In simulations, a thin bar undergoes a rapid (<1 Gyr) event called "buckling," during which the inner…
Strong galactic bars produced in simulations tend to undergo a period of buckling instability that weakens and thickens them and forms a boxy/peanut structure in their central parts. This theoretical prediction has been confirmed by…
The Milky Way is a barred galaxy whose central bulge has a box/peanut shape and consists of multiple stellar populations with different orbit distributions. This review describes dynamical and chemo-dynamical equilibrium models for the…
We analyse the output of the hi-res cosmological zoom-in simulation ErisBH to study self-consistently the formation of a strong stellar bar in a Milky Way-type galaxy and its effect on the galactic structure, on the central gas distribution…