Search Publications
Subaru/CHARIS High-resolution Mode Spectroscopy of the Brown Dwarf Companion HD 33632 Ab
Jensen-Clem, Rebecca; Lewis, Briley L.; Fitzgerald, Michael P. +6 more
Brown dwarfs (BDs) are model degenerate in age and mass. High-contrast imaging and spectroscopy of BD companions to host stars where the mass and age can be independently constrained by dynamics and stellar age indicators, respectively, provide valuable tests of BD evolution models. In this paper, we present a new epoch of Subaru/CHARIS H- and K-b…
On the Kinematic Nature of Apparent Disks at High Redshifts: Local Counterparts are Not Dominated by Ordered Rotation but by Tangentially Anisotropic Random Motion
Cappellari, Michele; Gao, Hua; Peng, Yingjie +2 more
It is not straightforward to physically interpret the apparent morphology of galaxies. Recent observations by the James Webb Space Telescope (JWST) revealed a dominant galaxy population at high redshifts (z > 2) that were visually classified as disks for their flattened shapes and/or exponential light profiles. The extensively accepted interpre…
SAUNAS. I. Searching for Low Surface Brightness X-Ray Emission with Chandra/ACIS
Koekemoer, Anton M.; Laine, Seppo; Lopez-Rodriguez, Enrique +8 more
We present Selective Amplification of Ultra Noisy Astronomical Signal (SAUNAS), a pipeline designed for detecting diffuse X-ray emission in the data obtained with the Advanced CCD Imaging Spectrometer (ACIS) of the Chandra X-ray Observatory. SAUNAS queries the available observations in the Chandra archive and performs photometric calibration, poin…
Supernova Ejecta with Crystalline Silicate Dust in the Supernova Remnant MSH 15–52
Onaka, Takashi; Koo, Bon-Chul; Kim, Hyun-Jeong
IRAS 15099-5856 in the young supernova remnant (SNR) MSH 15‑52 is the first and only SNR-associated object with crystalline silicate dust detected so far, although its nature and the origin of the crystalline silicate are still unclear. In this paper, we present high-resolution mid-infrared (MIR) imaging observations of the bright central compact …
Systematic Study of the Inner Structure of Molecular Tori in Nearby U/LIRGs Using Velocity Decomposition of CO Rovibrational Absorption Lines
Onishi, Shusuke; Nakagawa, Takao; Baba, Shunsuke +6 more
Determining the inner structure of the molecular torus around an active galactic nucleus is essential for understanding its formation mechanism. However, spatially resolving the torus is difficult because of its small size. To probe the clump conditions in the torus, we therefore perform the systematic velocity-decomposition analyses of the gaseou…
The COS CGM Compendium. V. The Dichotomy of O VI Associated with Low- and High-metallicity Cool Gas at z < 1
Sameer; Fox, Andrew J.; Lehner, Nicolas +3 more
We analyze the O VI content and kinematics for 126 H I-selected absorbers at 0.14 ≲ z ≲ 0.73 for which the metallicities of their cool photoionized phase have been determined. We separate the absorbers into 100 strong Lyα forest systems (SLFSs with 15 ≲ log N(H I) < 16.2) and 26 partial Lyman Limit systems (pLLSs with 16.2 ≤ log N(H I) ≤ 17.2).…
JWST Imaging of Edge-on Protoplanetary Disks. III. Drastic Morphological Transformation Across the Mid-infrared in Oph163131
Duchêne, Gaspard; Wolff, Schuyler G.; Perrin, Marshall D. +6 more
We present JWST broadband images of the highly inclined protoplanetary disk SSTc2d J163131.2-242627 (Oph163131) from 2.0 to 21 µm. The images show a remarkable evolution in disk structure with wavelength, quite different from previous JWST observations of other edge-on disks. At 2.0 and 4.4 µm, Oph163131 shows two scattering surfaces s…
X-Ray Spectroscopy of the Dwarf Nova Z Chamaeleontis in Quiescence and Outburst Using the XMM-Newton Observatory
Drake, Jeremy J.; Balman, Şölen; Godon, Patrick +1 more
We present X-ray spectroscopy of the SU UMa–type dwarf nova Z Chamaeleontis using the European Photon Imaging Camera and reflection grating spectrometer (RGS) instruments on board the XMM-Newton observatory. The quiescent system can be modeled by collisional equilibrium (CIE) or nonequilibrium plasma models, yielding a kT of 8.2–13.0 keV at a lumi…
A Spectroscopic and Interferometric Study of W Serpentis Stars. I. Circumbinary Outflow in the Interacting Binary W Serpentis
Gies, Douglas R.; Shepard, Katherine; Monnier, John D. +6 more
W Serpentis is an eclipsing binary system and the prototype of the Serpentid class of variable stars. These are interacting binaries experiencing intense mass transfer and mass loss. However, the identities and properties of both stars in W Ser remain a mystery. Here, we present an observational analysis of high-quality, visible-band spectroscopy …
Effects of Background Solar Wind and Drag Force on the Propagation of Coronal-mass-ejection-driven Shocks
Wood, Brian E.; Wu, Chin-Chun; Liou, Kan +1 more
The propagation of interplanetary shocks, particularly those driven by coronal mass ejections (CMEs), is still an outstanding question in heliophysics and space weather forecasting. Here, we address the effects of the ambient solar wind on the propagation of two similar CME-driven shocks from the Sun to Earth. The two shock events (CME03, 2010 Apr…