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Compositional Diversity in the Atmospheres of Hot Neptunes, with Application to GJ 436b
Fortney, J. J.; Moses, J. I.; Madhusudhan, N. +6 more
Neptune-sized extrasolar planets that orbit relatively close to their host stars—often called "hot Neptunes"—are common within the known population of exoplanets and planetary candidates. Similar to our own Uranus and Neptune, inefficient accretion of nebular gas is expected produce hot Neptunes whose masses are dominated by elements heavier than …
Spiral Arms in the Asymmetrically Illuminated Disk of MWC 758 and Constraints on Giant Planets
Kuzuhara, M.; Tamura, M.; Ishii, M. +71 more
We present the first near-IR scattered light detection of the transitional disk associated with the Herbig Ae star MWC 758 using data obtained as part of the Strategic Exploration of Exoplanets and Disks with Subaru, and 1.1 µm Hubble Space Telescope/NICMOS data. While submillimeter studies suggested there is a dust-depleted cavity with r = …
Calibrating C-IV-based Black Hole Mass Estimators
Park, Daeseong; Denney, Kelly D.; Woo, Jong-Hak +1 more
We present the single-epoch black hole mass estimators based on the C IV λ1549 broad emission line, using the updated sample of the reverberation-mapped active galactic nuclei and high-quality UV spectra. By performing multi-component spectral fitting analysis, we measure the C IV line widths (FWHMC IV and line dispersion, σC IV <…
Far-ultraviolet Detection of the Suspected Subdwarf Companion to the Be Star 59 Cygni
Gies, Douglas R.; Peters, Geraldine J.; Pewett, Tiffany D. +2 more
We report on the detection of a hot subdwarf component in the Be binary system, 59 Cygni. The spectral signature is found in cross-correlation functions of photospheric model spectra with far-ultraviolet spectra obtained by the International Ultraviolet Explorer Satellite, and we used radial velocities from the cross-correlation functions to deter…
Weak Hard X-Ray Emission from Two Broad Absorption Line Quasars Observed with NuSTAR: Compton-thick Absorption or Intrinsic X-Ray Weakness?
Harrison, F. A.; Stern, D.; Zhang, W. W. +22 more
We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus and the accretion-disk wind. The two targets are amo…
C IV Line-width Anomalies: The Perils of Low Signal-to-noise Spectra
Kochanek, C. S.; Vestergaard, M.; Peterson, B. M. +3 more
Comparison of six high-redshift quasar spectra obtained with the Large Binocular Telescope with previous observations from the Sloan Digital Sky Survey shows that failure to correctly identify absorption and other problems with accurate characterization of the C IV λ1549 emission line profile in low signal-to-noise (S/N) data can severely limit th…
The Chemical Properties of Low-redshift QSOs
Nagao, Tohru; Kim, Sang Chul; Woo, Jong-Hak +1 more
We investigate the chemical properties of low-z QSOs, using archival UV spectra obtained with the Hubble Space Telescope and International Ultraviolet Explorer for a sample of 70 Palomar-Green QSOs at z < 0.5. By utilizing the flux ratios of UV emission lines (i.e., N V/C IV, (Si IV+O IV])/C IV, and N V/He II) as metallicity indicators, we comp…
Precision Measurement of The Most Distant Spectroscopically Confirmed Supernova Ia with the Hubble Space Telescope
Huang, X.; Wang, L.; Lidman, C. +26 more
We report the discovery of a redshift 1.71 supernova in the GOODS-North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or neighboring galaxies. Although the rest-frame-sampled range is too blue to include any Si II line, a principal component analysis allows us to confirm it as a Type Ia supe…
The Detection of C60 in the Well-characterized Planetary Nebula M1-11
Meixner, M.; Otsuka, Masaaki; Yanagisawa, K. +4 more
We performed multiwavelength observations of the young planetary nebula (PN) M1-11 and obtained its elemental abundances, dust mass, and the evolutionary status of the central star. The AKARI/IRC, VLT/VISIR, and Spitzer/IRS spectra show features due to carbon-rich dust, such as the 3.3, 8.6, and 11.3 µm features due to polycyclic aromatic hy…
Far-ultraviolet Observations of Outflows from Infrared-luminous Galaxies
Schaerer, Daniel; Leitherer, Claus; Chandar, Rupali +2 more
We obtained medium-resolution ultraviolet (UV) spectra between 1150 and 1450 Å of the four UV-bright, infrared-luminous starburst galaxies IRAS F08339+6517, NGC 3256, NGC 6090, and NGC 7552 using the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The selected sightlines toward the starburst nuclei probe the properties of the rece…