相关论文: Detection of a Stellar Halo in NGC 4244

We report optical photometry and HI synthesis observations of the southern edge-on S_c,d galaxy IC5249. The observations were carried out primarily to determine if IC5249 has a red halo surrounding it similar to the halo that has been…

The results of the stellar photometry of the images ACS/WFC and WFPC2 of the HST are used to study stellar population and spatial distribution of stars in three edge-on galaxies: NGC 891, NGC 4144 and NGC 4244. The measuring of the number…

We show initial results from our ongoing HST GHOSTS survey of the resolved stellar envelopes of 14 nearby, massive disk galaxies. In hierarchical galaxy formation the stellar halos and thick disks of galaxies are formed by accretion of…

We analyze the outer regions of M33, beyond 15 kpc in projected distance from its center using Subaru/HSC multi-color imaging. We identify Red Giant Branch (RGB) stars and Red Clump (RC) stars using the surface gravity sensitive $NB515$…

We have obtained deep surface photometry of the edge-on spiral galaxy NGC 4244. Our data reliably reach 27.5 R magnitude arcsec^{-2}, a significant improvement on our earlier deep CCD surface photometry of other galaxies. NGC 4244 is a…

In a previous paper (Olling 1995, astro-ph/9505002) a method was developed to determine the shapes of dark matter halos of spiral galaxies from an accurate determination of the rotation curve, the flaring of the gas layer and the velocity…

We have imaged the halo populations of a sample of nearby spiral galaxies using the Wide Field Planetary Camera 2 on broad the Hubble Space Telescope with the aim of studying the stellar population properties and relating them to those of…

In a previous paper (Olling 1995, \aj, 110, 591; astro-ph/9505002) a method was developed to determine the shapes of dark matter halos of spiral galaxies from an accurate determination of the rotation curve, the flaring of the gas layer and…

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,…

Aims. The extraplanar stellar populations of highly-inclined disk galaxies IC 2233, IC 5052, NGC 4631 and NGC 5023 are analyzed with the goal to quantify their vertical extent and structure. Methods. Based on the single-star photometry, we…

We present a direct detection of the stellar halo of the edge-on S0 galaxy NGC 3957, using ultra-deep VLT/VIMOS V and R images. This is achieved with a sky subtraction strategy based on infrared techniques. These observations allow us to…

We have used the ACS and WFC3 cameras on board HST to resolve stars in the halo of the nearest giant elliptical (gE) galaxy NGC 5128 out to a projected distance of 140 kpc (25 effective radii, Reff) along the major axis and 90 kpc (16 Reff)…

We report on the detection of a stellar halo around NGC 1560, a 10^9 Mo spiral galaxy member of the Maffei group. We obtained deep images in the r and i bands using the 10.4m Gran Telescopio Canarias in a field centered at ~ 3.7 arcmin…

We present the first integral field spectroscopy observations of the two planetary nebulae NGC3242 and NGC4361 with the VIMOS instrument attached to VLT-UT3. By co-adding a large number of spaxels we reach an emission line detection limit…

In a previous paper (Paper I) a method was developed to determine the shapes of dark matter halos of spiral galaxies from the flaring and velocity dispersion of the gas layer. Here I present the results for the almost edge-on Scd galaxy NGC…

I present sensitive high resolution HI VLA B+C+D array observations of the edge-on Scd galaxy NGC 4244. The gas layer of NGC 4244 is rather symmetric in all respects, i.e. the surface density distribution, flaring and warping, so that the…

We present deep CCD surface photometry in the Gunn g, r, i system and spectroscopy of the cD galaxy at the centre of the cluster A3284 at z = 0.15. The brightness profile of the galaxy has been tracked up to 40 arcsec (142 kpc) from the…

Using long exposures taken in the V and I bands with a 4096$\times$4096 pixel CCD array at the prime focus of the Canada-France-Hawaii telescope, we have confirmed the discovery by Sackett et al. (1994) of a flat, faint luminous halo around…

Using the Hubble Space Telescope, we have resolved individual red-giant branch stars in the halos of eight nearby spiral galaxies. The fields lie at projected distances between 2 and 13 kpc along the galaxies' minor axes. The data set…

The extended stellar halos of galaxies contain important clues for investigating their assembly history and evolution. We investigate the resolved stellar content and the extended halo of NGC 5128 as a function of galactocentric distance.…