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Related papers: Streams, Shells, and Substructures in the Accretio…

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A candidate diffuse stellar substructure was previously reported in the halo of the nearby dwarf starburst galaxy NGC 4449 by Karachentsev et al. We map and analyze this feature using a unique combination of deep integrated-light images…

We present a chemical abundance analysis of 300S-1, the brightest likely member star of the 300 km/s stream near the faint satellite galaxy Segue 1. From a high-resolution Magellan/MIKE spectrum we determine a metallicity of [Fe/H] = -1.46…

Astrophysics of Galaxies · Physics 2015-06-15 Anna Frebel , Ragnhild Lunnan , Andrew R. Casey , John E. Norris , Rosemary F. G. Wyse , Gerard Gilmore

We present six simulations of galactic stellar haloes formed by the tidal disruption of accreted dwarf galaxies in a fully cosmological setting. Our model is based on the Aquarius project, a suite of high resolution N-body simulations of…

Stellar streams are sensitive laboratories for understanding the small-scale structure in our Galaxy's gravitational field. Here, we analyze the morphology of the $300S$ stellar stream, which has an eccentric, retrograde orbit and thus…

We report the discovery of significant stellar substructure in the halo and outer disk of our nearest large galactic neighbour, M31. Our deep panoramic survey with the Isaac Newton Telescope Wide Field Camera currently maps out an area of…

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

We analyse the M31 halo and its substructure within a projected radius of 120 kpc using a combination of Subaru/HSC $\textit{NB515}$ and CFHT/MegaCam $\textit{g}$- \& $\textit{i}$-bands. We succeed in separating M31's halo stars from…

A series of new radio-continuum (lambda=20 cm) mosaic images focused on the NGC 300 galactic system were produced using archived observational data from the VLA and/or ATCA. These new images are both very sensitive (rms=60 microJy) and…

[Abrigded] We have started a new deep, multi-imaging survey of the Fornax cluster, dubbed Fornax Deep Survey (FDS), at the VLT Survey Telescope. In this paper we present the deep photometry inside two square degrees around the bright galaxy…

In 2008 it was reported that the stellar stream of the edge-on spiral NGC5907 loops twice around the galaxy, enveloping it in a giant corkscrew-like structure. Here we present imaging of this iconic object with the Dragonfly Telephoto…

We present a deep photometric survey of M31, conducted with the CFHT and INT, covering the inner 50 kpc of the galaxy, the Southern quadrant out to 150 kpc, and extending to M33. This is the first systematic panoramic study of this very…

We present the preliminary results of a deep (167 ks) ROSAT HRI observation of the cD galaxy NGC1399 in the Fornax cluster. We find, in agreement with previous observations, an extended (41 Kpc adopting a distance of 19 Mpc) gaseous halo…

Astrophysics · Physics 2007-05-23 M. Paolillo , G. Fabbiano , G. Peres , D. -W. Kim

We present a renewed look at M31's Giant Stellar Stream along with the nearby structures Stream C and Stream D, exploiting a new algorithm capable of fitting to the red giant branch (RGB) of a structure in both colour and magnitude space.…

We present a structural analysis of NGC891, an edge-on galaxy that has long been considered to be an analogue of the Milky Way. Using starcounts derived from deep HST/ACS images, we detect the presence of a thick disk component in this…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Rodrigo Ibata , Mustapha Mouhcine , Marina Rejkuba

This paper explores the mapping between the observable properties of a stellar halo in phase- and abundance-space and the parent galaxy's accretion history in terms of the characteristic epoch of accretion and mass and orbits of progenitor…

(Abridged) We have obtained new spectrophotometric data for 28 HII regions in the spiral galaxy NGC 300, a member of the nearby Sculptor Group. The detection of auroral lines, including [OIII]4363, [SIII]6312 and [NII]5755, has allowed us…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 Fabio Bresolin , Wolfgang Gieren , Rolf-Peter Kudritzki , Grzegorz Pietrzynski , Miguel A. Urbaneja , Giovanni Carraro

We have obtained Magellan/IMACS and HST/ACS imaging data that resolve red giant branch stars in the stellar halo of the starburst galaxy NGC 253. The HST data cover a small area, and allow us to accurately interpret the ground-based data,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jeremy Bailin , Eric F. Bell , Samantha N. Chappell , David J. Radburn-Smith , Roelof S. de Jong

AIMS: The main goal of this work is to study possible signs of asymmetry in the bright optical transient in NGC300, with the aim of getting independent information on the explosion mechanism, the progenitor star and its circumstellar…

Solar and Stellar Astrophysics · Physics 2015-05-13 F. Patat , J. R. Maund , S. Benetti , M. -T. Botticella , E. Cappellaro , A. Harutyunyan , M. Turatto

This study presents a tomographic survey of a subset of the outer halo (10-40 kpc) drawn from the Sloan Digital Sky Survey Data Release 6. Halo substructure on spatial scales of $>3$ degrees is revealed as an excess in the local density of…

Astrophysics of Galaxies · Physics 2015-05-14 Stefan C. Keller

We present the discovery of NGC253-SNFC-dw1, a new satellite galaxy in the remote stellar halo of the Sculptor Group spiral, NGC 253. The system was revealed using deep resolved star photometry obtained as part of the Subaru Near-Field…

We report on the discovery of an extended stellar halo surrounding the distant Galactic globular cluster NGC 5694, based on new deep (V ~ 24.5) wide-field (24' * 20') photometry acquired with VIMOS at VLT. Stars with colour and magnitude…

Solar and Stellar Astrophysics · Physics 2015-05-28 M. Correnti , M. Bellazzini , E. Dalessandro , A. Mucciarelli , L. Monaco , M. Catelan