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Related papers: A Magellanic origin for the Virgo substructure

200 papers

We present a panoramic map of the entire Milky Way halo north of dec~-30 degrees (~30,000 deg^2), constructed by applying the matched-filter technique to the Pan-STARRS1 3Pi Survey dataset. Using single-epoch photometry reaching to g~22, we…

Two studies have recently reported the discovery of pronounced Halo substructure in the Sloan Digital Sky Survey (SDSS) commissioning data. Here we show that this Halo substructure is almost in its entirety due to the expected tidal stream…

Astrophysics · Physics 2009-05-29 Rodrigo Ibata , Michael Irwin , Geraint Lewis , Andrea Stolte

Recent observations have revealed streams of gas and stars in the halo of the Milky Way that are the debris from interactions between our Galaxy and some of its dwarf companion galaxies; the Sagittarius dwarf galaxy and the Magellanic…

Astrophysics · Physics 2011-03-10 Rodrigo Ibata , Michael Irwin , Geraint Lewis , Annette Ferguson , Nial Tanvir

RR Lyrae stars (RRLS) belong to population II and are generally used as a tracer of the host galaxy halo. The surface as well as vertical distribution of RRLS in the inner Large Magellanic Cloud (LMC) are studied to understand whether these…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Annapurni Subramaniam , Smitha Subramanian

We map the three dimensional extent of the Virgo Over-density by combining distance information from RR Lyrae variables and projected spatial information from SEKBO (Keller et al. 2008) and Sloan Digital Sky Survey (SDSS) DR6 photometry.…

Astrophysics of Galaxies · Physics 2009-11-13 Stefan C. Keller , Gary S. Da Costa , Sayuri L. Prior

Using Blue Horizontal Branch stars identified in the Dark Energy Survey Year 1 data, we report the detection of an extended and lumpy stellar debris distribution around the Magellanic Clouds. At the heliocentric distance of the Clouds,…

Astrophysics of Galaxies · Physics 2015-12-23 Vasily Belokurov , Sergey Koposov

The distribution of RR Lyrae stars (RRLS) in the inner Large Magellanic Cloud (LMC), and the structure of the halo of the LMC delineated by these stars are studied here. RRLS identified by the OGLE II survey are used to estimate their…

Astrophysics · Physics 2009-11-11 Annapurni Subramaniam

Understanding the formation and evolutionary history of the Milky Way requires detailed mapping of its stellar components, which preserve fossil records of the Galaxy's assembly through cosmic time. RR Lyrae stars are particularly…

Astrophysics of Galaxies · Physics 2026-03-19 Madeline Lucey , Cecilia Mateu , Adrian Price-Whelan , David Hogg , Hans-Walter Rix , Robyn Sanderson

RR Lyrae stars are standard candles with characteristic photometric variability and serve as powerful tracers of Galactic structure, substructure, accretion history, and dark matter content. Here we report the discovery of distant RR Lyrae…

The dominant gaseous structure in the Galactic halo is the Magellanic Stream, an extended network of neutral and ionized filaments surrounding the Large and Small Magellanic Clouds (LMC/SMC), the two most massive satellite galaxies of the…

Astrophysics of Galaxies · Physics 2020-09-10 Scott Lucchini , Elena D'Onghia , Andrew J Fox , Chad Bustard , Joss Bland-Hawthorn , Ellen Zweibel

Overdensities in the radial phase space $(r,v_r)$ of the Milky Way's halo have previously been associated with the phase-mixed debris of a highly radial merger event, such as Gaia Sausage-Enceladus. We present and test an alternative theory…

Astrophysics of Galaxies · Physics 2024-08-13 Adam M. Dillamore , Vasily Belokurov , N. Wyn Evans

We characterize substructure in the simulated stellar halos of Cooper et al. (2010) which were formed by the disruption of satellite galaxies within the cosmological N-body simulations of galactic halos of the Aquarius Project. These…

Astrophysics of Galaxies · Physics 2015-05-27 Amina Helmi , A. P. Cooper , S. D. M. White , S. Cole , C. S. Frenk , J. F. Navarro

We present an improved analysis of halo substructure traced by RR Lyrae stars in the SDSS stripe 82 region. With the addition of SDSS-II data, a revised selection method based on new ugriz light curve templates results in a sample of 483 RR…

We present results from the analysis of 2997 fundamental mode RR Lyrae variables located in the Small Magellanic Cloud (SMC). For these objects near-infrared time-series photometry from the VISTA survey of the Magellanic Clouds system (VMC)…

In the hierarchical formation scenario in which the outer halo of the Milky Way is the result of the continuous accretion of low-mass galaxies, a fraction of the Galactic globular cluster system might have originated in and been accreted…

The local stellar halo of the Milky Way contains the debris from several past accretion events. Here we study in detail the structure and properties of nearby debris associated with the Helmi streams, originally identified as an overdensity…

Astrophysics of Galaxies · Physics 2022-03-14 Emma Dodd , Amina Helmi , Helmer H. Koppelman

It is now generally believed that galaxies were built up through gravitational amplification of primordial fluctuations and the subsequent merging of smaller precursor structures. The stars of the structures that assembled to form the Milky…

Astrophysics · Physics 2012-08-27 Amina Helmi , Simon D. M. White , P. Tim de Zeeuw , and HongSheng Zhao

The halo of the Milky Way has long been hypothesized to harbour significant amounts of merger debris. This view has been supported over more than a decade by wide-field photometric surveys which have revealed the outer halo to be lumpy. The…

Astrophysics of Galaxies · Physics 2019-05-01 Helmer H. Koppelman , Amina Helmi , Davide Massari , Sebastian Roelenga , Ulrich Bastian

The hierarchical structure formation model predicts that stellar halos should form, at least partly, via mergers. If this was a predominant formation channel for the Milky Way's halo, imprints of this merger history in the form of moving…

Astrophysics of Galaxies · Physics 2017-02-01 Amina Helmi , Jovan Veljanoski , Maarten A. Breddels , Hao Tian , Laura V. Sales

We describe first results of a spectroscopic probe of selected fields from the Grid Giant Star Survey. Multifiber spectroscopy of several hundred stars in a strip of eleven fields along delta approximately -17^{circ}, in the range 12 <~…