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Deep Multiwaveband Observations of the Jets of 0208-512 and 1202-262
Perlman, Eric S.; Georganopoulos, Markos; Gelbord, Jonathan +8 more
We present deep Hubble Space Telescope, Chandra, Very Large Array, and Australia Telescope Compact Array images of the jets of PKS 0208-512 and PKS 1202-262, which were found in a Chandra survey of a flux-limited sample of flat-spectrum radio quasars with jets. We discuss in detail their X-ray morphologies and spectra. We find optical emission fro…
Deep Infrared ZAMS Fits to Benchmark Open Clusters Hosting Delta Scuti Stars
Turner, D. G.; Majaess, D. J.; Lane, D. J. +1 more
This research aims to secure precise distances for cluster δ Scuti stars in order to investigate their properties via a VI Wesenheit framework. Deep JHKs color-color and zero-age main sequence (ZAMS) relations derived from ~700 unreddened stars featuring 2MASS photometry and precise Hipparcos parallaxes (d≤25 pc) are applied to establish distances…
Carbon-chain Species in Warm-up Models
Herbst, Eric; Hassel, George E.; Harada, Nanase
In previous warm-up chemical models of the low-mass star-forming region L1527, we investigated the evolution of carbon-chain unsaturated hydrocarbon species when the envelope temperature is slightly elevated to T ≈ 30 K. These models demonstrated that enhanced abundances of such species can be explained by gas-phase ion-molecule chemistry followin…
Accuracy of multi-point boundary crossing time analysis
Haaland, S.; Paschmann, G.; Vogt, J.
Recent multi-spacecraft studies of solar wind discontinuity crossings using the timing (boundary plane triangulation) method gave boundary parameter estimates that are significantly different from those of the well-established single-spacecraft minimum variance analysis (MVA) technique. A large survey of directional discontinuities in Cluster data…
Gravitational Lens Candidates in the E-CDFS
Barden, M.; Häußler, B.; Jahnke, K. +4 more
We report 10 lens candidates in the Extended Chandra Deep Field South from the GEMS survey. Nine of the systems are new detections and only one of the candidates is a known lens system. For the most promising five systems including the known lens system, we present results from preliminary lens mass modeling, which tests if the candidates are plau…
Penetrating the Homunculus—Near-Infrared Adaptive Optics Images of Eta Carinae
Smith, Nathan; Humphreys, Roberta M.; Davidson, Kris +3 more
Near-infrared adaptive optics imaging with the Near-Infrared Coronagraphic Imager (NICI) and NaCO reveal what appears to be a three-winged or lobed pattern, the "butterfly nebula," outlined by bright Brγ and H2 emission and light scattered by dust. In contrast, the [Fe II] emission does not follow the outline of the wings, but shows an …
Submillimeter Sources behind the Massive Lensing Clusters A370 and A2390
Chen, Chian-Chou; Williams, Jonathan P.; Wang, Wei-Hao +2 more
We report 850 µm Submillimeter Array (SMA) observations of four gravitationally lensed submillimeter galaxies (SMGs), A370-2, A2390-1, A2390-3, and A2390-4, which were originally discovered with the Submillimeter Common-User Bolometer Array (SCUBA). Our SMA detection of A370-2 with a submillimeter flux of 7.95 ± 0.60 mJy unambiguously identi…
Hubble Space Telescope Spectral Observations Near the He II Lyα Break: Implications for He II Reionization
Anderson, Scott F.; Schneider, Donald P.; York, Donald G. +4 more
Quasars that allow the study of intergalactic medium (IGM) He II are very rare, since they must be at high redshift along sightlines free of substantial hydrogen absorption, but recent work has dramatically expanded the number of such quasars known. We analyze two dozen higher-redshift (z = 3.1-3.9) low-resolution He II quasar spectra from the Hub…
Dynamic Inner Magnetosphere: A Tutorial and Recent Advances The Dynamic Magnetosphere
Ebihara, Y.; Miyoshi, Y. S.
Is There a Black Hole in NGC 4382?
Gebhardt, Karl; Kormendy, John; Lauer, Tod R. +5 more
We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph observations of the galaxy NGC 4382 (M85) and axisymmetric models of the galaxy to determine mass-to-light ratio (Upsilon V ) and central black hole mass (M BH). We find Upsilon V = 3.74 ± 0.1 M sun/L sun and M …