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XMM-Newton Observations of Broad Iron Kα Emission from Seyfert 1.9 Galaxy MCG -5-23-16
Schurch, N. J.; Dewangan, G. C.; Griffiths, R. E.
XMM-Newton observations of the bright Seyfert 1.9 galaxy MCG -5-23-16 have revealed a broad Fe Kα emission line that is nearly symmetric in contrast to the broad and redshifted asymmetric Fe Kα line sometimes observed from Seyfert 1 galaxies. The Fe Kα line has two distinct components-a narrow unresolved component with an equivalent width of ~40 e…
Ground-based Near-Infrared Imaging of the HD 141569 Circumstellar Disk
Augereau, J. -C.; Boccaletti, A.; Hahn, J. +1 more
We present the first ground-based near-infrared image of the circumstellar disk around the post-Herbig Ae/Be star HD 141569A initially detected with the Hubble Space Telescope (HST). Observations were carried out in the near-IR (2.2 µm) at the Palomar 200 inch telescope using the adaptive optics system PALAO. The main large-scale asymmetric …
The Absorption and Emission Kinematics in the z=0.7450 Mg II Absorber toward Q1331+17
Ellison, Sara L.; Sawicki, Marcin; Mallén-Ornelas, Gabriela
We present a comparative analysis of the galaxy emission and quasar (QSO) absorption kinematics of a zabs~0.7450 Mg II system and its candidate absorbing galaxy (G5) located 3.86" (28.3 h-170 kpc) from the QSO. We have obtained a spectrum of the galaxy candidate, previously identified as a luminous edge-on disk, an…
Small Magellanic Cloud-Type Interstellar Dust in the Milky Way
Gordon, Karl D.; Clayton, Geoffrey C.; Valencic, Lynne A. +1 more
It is well known that the sight line toward HD 204827 in the cluster Trumpler 37 shows a UV extinction curve that does not follow the average Galactic extinction relation. However, when a dust component, foreground to the cluster, is removed, the residual extinction curve is identical to that found in the SMC within the uncertainties. The curve is…
Revealing New Physical Structures in the Supernova Remnant N63A through Chandra Imaging Spectroscopy
Hughes, John P.; Slane, Patrick O.; Warren, Jessica S.
We present Chandra X-ray observations of the supernova remnant (SNR) N63A in the Large Magellanic Cloud (LMC). N63A, one of the brightest LMC remnants, is embedded in an H II region and is probably associated with an OB association. The optical remnant consists of three lobes of emission contained within the approximately 3 times larger X-ray remn…
The Leo I Cloud: Secular Nuclear Evolution of NGC 3379, NGC 3384, and NGC 3368?
Moiseev, A. V.; Chavushyan, V. H.; Sil'chenko, O. K. +2 more
The central regions of the three brightest members of the Leo I galaxy group-NGC 3368, NGC 3379, and NGC 3384-are investigated by means of two-dimensional spectroscopy. In all three galaxies we have found separate circumnuclear stellar and gaseous subsystems-more probably, disks-whose spatial orientations and spins are connected to the spatial ori…
Molecular Gas and the Nuclear Star Cluster in IC 342: Sufficient Inflow for Recurring Star Formation Events?
Meier, David S.; Böker, Torsten; Schinnerer, Eva
We present high spatial resolution (1.2") millimeter-interferometric observations of the 12CO (2-1) line emission in the central 300 pc of the late-type spiral galaxy IC 342. The data, obtained with the Owens Valley Radio Observatory, allow first-time detection of a molecular gas disk that coincides with the luminous young stellar clust…
Some Constraints on the Effects of Age and Metallicity on the Low-Mass X-Ray Binary Formation Rate
Kundu, Arunav; Zepf, Stephen E.; Maccarone, Thomas J. +1 more
We have studied the low-mass X-ray binary (LMXB) populations within and outside globular clusters (GCs) in NGC 4365 and NGC 3115. Using published age and metallicity constraints from optical and IR observations of their GCs, we do not find any evidence for an increase in the LMXB formation rate in the intermediate-age cluster population of NGC 436…
A V-Band Survey for Variable Galactic Nuclei in the Hubble Deep Field
Gilliland, Ronald L.; Sarajedini, Vicki L.; Kasm, Christina
We present the results of a two-epoch variability survey in the Hubble Deep Field with the goal of investigating the population of active galactic nuclei (AGNs) to z~=1. The high resolution and stability of the Hubble Space Telescope allow accurate photometry to be obtained within subarcsecond apertures, resulting in the ability to probe much lowe…
An Intrinsic Absorption Complex toward RX J1230.8+0115: Geometry and Photoionization Conditions
Charlton, Jane C.; Sembach, Kenneth R.; Ganguly, Rajib +1 more
We present Hubble Space Telescope/Space Telescope Imaging Spectrograph and Far Ultraviolet Spectroscopic Explorer spectra of the quasar RX J1230.8+0115 (V=14.4,z=0.117). In addition to Galactic, Virgo, and intervening absorption, this quasar is host to a remarkable intrinsic absorption complex. Four narrow absorption line systems, strong in C IV, …