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Related papers: The Galactic Bar

200 papers

We compute a microlensing map for the Galactic bar. The predicted event rate and event duration distribution are consistent with the $55$ events recently reported by the MACHO and OGLE collaborations. Most of the events are due to lensing…

Astrophysics · Physics 2015-06-24 HongSheng Zhao , R. M. Rich , D. N. Spergel

In its first part, this paper summarizes recent work on the mass and shape of the Galactic dark halo. The second part presents a review of the large-scale structure of the Milky Way, and of the evidence that the inner Galaxy is dominated by…

Astrophysics · Physics 2009-11-11 Ortwin Gerhard

Microlensing is now a very popular observational astronomical technique. The investigations accessible through this effect range from the dark matter problem to the search for extra-solar planets. In this review, the techniques to search…

Astrophysics of Galaxies · Physics 2010-08-24 Marc Moniez

Observational data indicate that the Milky Way is a barred spiral galaxy. Computation facilities and availability of data from Galactic surveys stimulate the appearance of models of the Galactic structure. More efforts to build dynamical…

Astrophysics of Galaxies · Physics 2018-07-18 Tatiana A. Michtchenko , Jacques R. D. Lépine , Douglas A. Barros , Ronaldo S. S. Vieira

The structural parameters of a galaxy can be used to gain insight into its formation and evolution history. In this paper, we strive to compare the Milky Way's structural parameters to other, primarily edge-on, spiral galaxies in order to…

Astrophysics of Galaxies · Physics 2024-01-09 Jacob A. Guerrette , Aleksandr V. Mosenkov , Dallin Spencer , Zacory D. Shakespear

It has been known for some time that the Milky Way is a barred disk galaxy. More recently several studies inferred from starcount observations that the Galaxy must contain a separate, new, flat long bar component, twisted relative to the…

Astrophysics of Galaxies · Physics 2015-05-28 Inma Martinez-Valpuesta , Ortwin Gerhard

A general overview of the understanding of our Galaxy is presented following the lines of its main structures: halo, disc, bulge/bar. This review is emphasising some "Time Domain Astronomy" contributions. On the one hand the distance and…

Astrophysics of Galaxies · Physics 2019-09-04 Laurent Eyer

This chapter reviews the three-dimensional structure, age, kinematics, and chemistry of the Milky Way (MW) region within ~2 kpc from its center (hereafter referred to as the 'bulge') from an observational perspective. While not exhaustive…

Astrophysics of Galaxies · Physics 2024-12-03 Manuela Zoccali , Elena Valenti

Observations show a clear vertical metallicity gradient in the Galactic bulge, which is often taken as a signature of dissipative processes in the formation of a classical bulge. Various evidence shows, however, that the Milky Way is a…

Astrophysics of Galaxies · Physics 2015-06-12 Inma Martinez-Valpuesta , Ortwin Gerhard

The kinematics of the Milky Way bulge is known to be complex, reflecting the presence of multiple stellar components with distinct chemical and spatial properties. In particular, the bulge hosts a bar structure exhibiting cylindrical…

We use the continuity equation to derive a method for measuring the pattern speed of the Milky Way's bar/bulge from proper motion data. The method has minimal assumptions but requires complete coverage of the non-axisymmetric component in…

Astrophysics of Galaxies · Physics 2019-08-21 Jason L. Sanders , Leigh Smith , N. Wyn Evans

Recent large scale surveys of galactic bulge stars allowed to build a detailed map of the bulge kinematics. The bulge exhibits cylindrical rotation consistent with a disky origin which evolved through bar driven secular evolution. However…

Astrophysics of Galaxies · Physics 2016-07-06 Carine Babusiaux

We analyze the first-year MACHO collaboration observations of microlensing towards the Galactic center using a new direct likelihood technique that is sensitive to the distribution of the events on the sky. We consider the full set of 41…

Astrophysics · Physics 2007-05-23 Geza Gyuk

The Laser Interferometer Space Antenna (LISA) will enable Galactic gravitational wave (GW) astronomy by individually resolving $ > 10^4$ signals from double white dwarf (DWD) binaries throughout the Milky Way. In this work we assess for the…

Astrophysics of Galaxies · Physics 2025-10-03 Maite J. C. Wilhelm , Valeriya Korol , Elena M. Rossi , Elena D'Onghia

We generalize to elliptical models the argument of Kuijken (1997), which connects the microlensing optical depth towards the Galactic bulge to the Galactic rotation curve. When applied to the latest value from the MACHO collaboration for…

Astrophysics · Physics 2009-10-31 James Binney , Nicolai Bissantz , Ortwin Gerhard

Our Galaxy, the Milky Way, is a benchmark for understanding disk galaxies. It is the only galaxy whose formation history can be studied using the full distribution of stars from white dwarfs to supergiants. The oldest components provide us…

Astrophysics of Galaxies · Physics 2017-01-06 Joss Bland-Hawthorn , Ortwin Gerhard

We investigate the structure of the Milky Way by determining how features in a spatial map correspond to CO features in a velocity map. We examine structures including logarithmic spiral arms, a ring and a bar. We explore the available…

Astrophysics of Galaxies · Physics 2015-06-03 C. L. Dobbs , A. Burkert

We describe a new phenomenon of `bar damping' that may have played an important role in shaping the Milky Way bar and bulge as well as its spiral structure. We use a collisionless N-body simulation of a Milky Way-like galaxy initially…

Astrophysics of Galaxies · Physics 2016-11-07 Ewa L. Lokas

We compare distance resolved, absolute proper motions in the Milky Way bar/bulge region to a grid of made-to-measure dynamical models with well defined pattern speeds. The data are obtained by combining the relative VVV Infrared Astrometric…

Astrophysics of Galaxies · Physics 2022-04-29 Jonathan Clarke , Ortwin Gerhard

Much of our effort in understanding the long-term evolution and morphology of the Milky Way and other galaxies has focused on the equilibrium of its luminous disk. However, the interplay between all components, seen and unseen, is a major…

Astrophysics · Physics 2007-05-23 Martin D. Weinberg