English
Related papers

Related papers: Extended stellar substructure surrounding the Bo\"…

200 papers

Leo I is considered one of the youngest dwarf spheroidals (dSph) in the Local Group. Its isolation, extended star formation history (SFH), and recent perigalacticon passage (~1 Gyr ago) make Leo~I one of the most interesting nearby stellar…

The ultra-faint dwarf galaxy Hercules has an extremely elongated morphology with both photometric overdensities and kinematic members at large radii, suggesting that it may be tidally disrupting due to a previous close encounter with the…

The failure of standard cosmolocical models in accounting for the statistics of dwarf satellites and the rotation curve of gas-rich dwarf galaxies in detail has led us to examine whether earlier non-equilibrium models of dwarf spheroidal…

Astrophysics · Physics 2009-11-07 Ralf Klessen , HongSheng Zhao

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

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 report the discovery of a $>1^\circ$ ($\sim50$ kpc) long stellar tidal stream emanating from the dwarf galaxy DDO 44, a likely satellite of Local Volume galaxy NGC 2403 located $\sim70$ kpc in projection from its companion. NGC 2403 is a…

We investigate the spatial density configuration of stars around four metal-poor globular clusters (NGC 6266, NGC 6626, NGC 6642 and NGC 6723) in the Galactic bulge region using wide-field deep J, H, and K imaging data obtained with the…

Astrophysics of Galaxies · Physics 2015-06-23 Sang-Hyun Chun , Minhee Kang , DooSeok Jung , Young-Jong Sohn

Stars that escape globular clusters form tidal tails that are predominantly shaped by the global distribution of mass in the Galaxy, but also preserve a historical record of small-scale perturbations. Using deep $grz$ photometry from…

We investigate the evolution of substructure in cold dark matter halos using N-body simulations of tidal stripping of substructure halos (subhalos) within a static host potential. We find that halos modeled following the Navarro, Frenk &…

Astrophysics · Physics 2008-11-26 Eric Hayashi , Julio F. Navarro , James E. Taylor , Joachim Stadel , Thomas Quinn

(Abridged) We use N-body simulations to explore the effects of tidal stripping on the structure of dwarf spheroidal galaxies (dSphs). We model dSphs as King spheres embedded in NFW dark halos that orbit the Galactic potential on eccentric…

Astrophysics · Physics 2014-11-18 Jorge Penarrubia , Julio F. Navarro , Alan W. McConnachie , Nicolas F. Martin

(abridged) We present kinematic results for a sample of 387 stars located near Leo I based on spectra obtained with the MMT's Hectochelle spectrograph near the MgI/Mgb lines. We estimate the mean velocity error of our sample to be 2.4 km/s,…

Astrophysics · Physics 2009-11-13 Mario Mateo , Edward W. Olszewski , Matthew G. Walker

(Abridged) We performed a deep infrared imaging survey of 63 embedded young stellar objects (YSOs) located in the Taurus and Ophiuchus clouds to search for companions. The sample includes Class I and flat infrared spectrum protostellar…

Astrophysics · Physics 2009-11-10 G. Duchene , J. Bouvier , S. Bontemps , P. Andre , F. Motte

We use deep V-band surface photometry of five of the brightest elliptical galaxies in the Virgo cluster to search for diffuse tidal streams, shells, and plumes in their outer halos (r > 50 kpc). We fit and subtract elliptical isophotal…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Steven Janowiecki , J. Christopher Mihos , Paul Harding , John J. Feldmeier , Craig Rudick , Heather Morrison

We describe photometry improvements in the La Silla--Quest RR Lyrae star (RRLS) survey that enable it to reach distances from the Sun ($d_{\odot}$) $\sim 140$ kpc. We report the results of surveying $\sim 300~ {\rm deg}^2$ of sky around the…

Astrophysics of Galaxies · Physics 2024-02-06 P. S. Coppi , R. Zinn , C. Baltay , D. Rabinowitz , T. Girard , R. Howard , K. Ment , R. Rahman

Observations of the nebula S3 associated with the WO star in the galaxy IC 1613 and of an extended region surrounding S3 are reported. The star and bright core of the nebula were observed with a multipupil fiber spectrograph mounted on the…

Astrophysics · Physics 2009-11-06 T. A. Lozinskaya , A. V. Moiseev , V. L. Afanasiev , E. Wilcots , W. M. Goss

We report the discovery of two well-defined tidal tails emerging from the Hyades star cluster. The tails were detected in Gaia DR2 data by selecting cluster members in the three-dimensional galactocentric cylindrical velocity space. The…

Astrophysics of Galaxies · Physics 2019-01-16 Stefan Meingast , João Alves

We present stellar radial velocity data for the Draco dwarf spheroidal galaxy obtained using the AF2/WYFFOS instrument combination on the William Herschel Telescope. Our dataset consists of 186 member stars, 159 of which have good quality…

Astrophysics · Physics 2009-11-07 J. T. Kleyna , M. I. Wilkinson , N. W. Evans , G. Gilmore

We investigate the possibility that the dwarf galaxies Crater II and Hercules have previously been tidally stripped by the Milky Way. We present Magellan/IMACS spectra of candidate member stars in both objects. We identify 37 members of…

Astrophysics of Galaxies · Physics 2019-09-25 Sal Wanying Fu , Joshua D. Simon , Alex G. Alarcón Jara

We present deep $g$- and $r$-band Magellan/Megacam photometry of two dwarf galaxy candidates discovered in the Dark Energy Survey (DES), Grus I and Indus II (DES J2038-4609). For the case of Grus I, we resolved the main sequence turn-off…

Tidal interactions between massive galaxies and their satellites are fundamental processes in a Universe with L-Cold Dark Matter cosmology, redistributing material into faint features that preserve records of past galactic interactions.…