Unifying the planar bar and the boxy bulge of the Milky Way

Martinez-Valpuesta, I.; Gerhard, O.
February 2012
EPJ Web of Conferences;2012, Issue 19, p1
Conference Proceeding
For some time the Milky Way has been understood as a barred disk galaxy. Star count observations have provided evidence for two bars at apparently different orientations, the boxy bulge and a long planar bar. We report recent work in which we argued for a scenario where these observations can be reproduced with a single boxy bulge/bar: an evolved bar from the stellar disk and the corresponding boxy bulge generated from it through secular evolution and buckling instability. We calculated the star count distributions along different lines-of-sight for a simulated barred galaxy and an observer at the Sun position, and compared them with observations of red clump magnitude distributions. We found a good agreement between the model and the observations, even though the simulation has a single boxy bulge/bar. In this model, the different apparent orientations of the boxy bulge and planar bar are partially due to the volume effect and partially to the leading ends of the bar.


Related Articles

  • Chemical evolution of the Galactic bulge: different stellar populations and possible gradients. Grieco, V.; Matteucci, F.; Pipino, A.; Cescutti, G. // Astronomy & Astrophysics / Astronomie et Astrophysique;Nov2012, Vol. 548, p1 

    Context. The recent although controversial discovery of two main stellar populations in the Galactic bulge, one metal-poor with a spheroid kinematics and the other metal-rich with a bar-like kinematics, suggests a revision of the classical model for bulge formation. Aims. We aim at computing in...

  • Comparing HARPS and Kepler surveys The alignment of multiple-planet systems. Figueira, P.; Marmier, M.; Boué, G.; Lovis, C.; Santos, N. C.; Montalto, M.; Udry, S.; Pepe, F.; Mayor, M. // Astronomy & Astrophysics / Astronomie et Astrophysique;May2012, Vol. 541, p1 

    Context. The recent results of the HARPS and Kepler surveys provided us with a bounty of extrasolar systems. While the two teams extensively analyzed each of their data-sets, little work has been done comparing the two. Aims. We study a subset of the planetary population whose characterization...

  • Milky Way demographics with the VVV survey. Saito, R. K.; Minniti, D.; Dias, B.; Hempel, M.; Rejkuba, M.; Alonso-García, J.; Barbuy, B.; Catelan, M.; Emerson, J. P.; Gonzalez, O. A.; Lucas, P. W.; Zoccali, M. // Astronomy & Astrophysics / Astronomie et Astrophysique;Aug2012, Vol. 544 Issue 2, pA147-1 

    Context. The Milky Way (MW) bulge is a fundamental Galactic component for understanding the formation and evolution of galaxies, in particular our own. The ESO Public Survey VISTA Variables in the Via Láctea is a deep near-JR survey mapping the Galactic bulge and southern plane. Particularly...

  • Stellar ages through the corners of the boxy bulge. Valenti, E.; Zoccali, M.; Renzini, A.; Brown, T. M.; Gonzalez, O. A.; Minniti, D.; Debattista, V. P.; Mayer, L. // Astronomy & Astrophysics / Astronomie et Astrophysique;Dec2013, Vol. 559, p1 

    Aims. 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 color-magnitude diagrams have been obtained is indeed along...

  • 50-day Oscillation of Length-of-day Change. Lihua Ma; Yanben Han; Dechun Liao // Earth, Moon & Planets;Oct2008, Vol. 103 Issue 1/2, p1 

    Abstract  Variations of Earth’s rotation rate (length-of-day, LOD) occur over a wide range of time scales from a few hours to the geological age. Studies showed that the 50-day fluctuation exists in LOD change. In the present paper, the authors use wavelet technique to study the...

  • Counter-orbiting tidal debris as the origin of the MW DoS. Pawlowski, M. S. // EPJ Web of Conferences;2012, Issue 19, p1 

    The Milky Way satellite galaxies show a phase-space distribution that is not expected from the standard scenario of galaxy formation. This is a strong hint at them being of tidal origin, which would naturally explain their spacial distribution in a disc of satellites. It is shown that also their...

  • A bound system in the expanding universe with modified holographic Ricci dark energy and dark matter. Li, En-Kun; Zhang, Yu; Geng, Jin-Ling; Duan, Peng-Fei // Astrophysics & Space Science;Jan2015, Vol. 355 Issue 1, p187 

    The evolution of a bound system in the expanding background has been investigated in this paper. The background is described by a FRW universe with the modified holographic dark energy model, whose equation of state parameter changes with time and can cross the phantom boundary. To study the...

  • Characterizing direction of coupling from experimental observations. Bezruchko, Boris; Ponomarenko, Vladimir; Rosenblum, Michael G.; Pikovsky, Arkady S. // Chaos;Mar2003, Vol. 13 Issue 1, p179 

    We demonstrate that the direction of coupling of two interacting self-sustained electronic oscillators can be determined from the realizations of their signals. In our experiments, two electronic generators, operating in a periodic or a chaotic state, were subject to symmetrical or...

  • Extension of Bertrand's theorem and factorization of the radial Schrodinger equation.  // Journal of Mathematical Physics;Oct98, Vol. 39 Issue 10, p5253 

    Extends the Bertrand's theorem and factorization of the radial Schrodinger equation. Existence of closed orbits for suitable angular momentum in the isotropic harmonic oscillator; Correspondence between the classical orbits and operators; Presence of energy and lowering operators in quantum...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics