Search Publications
Chromophores from photolyzed ammonia reacting with acetylene: Application to Jupiter's Great Red Spot
Baines, K. H.; Carlson, R. W.; Simon, A. A. +2 more
The high altitude of Jupiter's Great Red Spot (GRS) may enhance the upward flux of gaseous ammonia (NH3) into the high troposphere, where NH3 molecules can be photodissociated and initiate a chain of chemical reactions with downwelling acetylene molecules (C2H2). These reactions, experimentally studied e…
Warm absorbers in X-rays (WAX), a comprehensive high-resolution grating spectral study of a sample of Seyfert Galaxies - II. Warm absorber dynamics and feedback to galaxies
Dewangan, Gulab C.; Guainazzi, Matteo; Laha, Sibasish +2 more
This paper is a sequel to the extensive study of warm absorber (WA) in X-rays carried out using high-resolution grating spectral data from XMM-Newton satellite (WAX-I). Here we discuss the global dynamical properties as well as the energetics of the WA components detected in the WAX sample. The slope of WA density profile (n ∝ r-α) esti…
A free-form mass model of the Hubble Frontier Fields cluster AS1063 (RXC J2248.7-4431) with over one hundred constraints
Broadhurst, Tom; Zheng, Wei; Lam, Daniel +5 more
We derive a free-form mass distribution for the massive cluster AS1063 (z = 0.348) using the completed optical imaging from the Hubble Frontier Fields programmme. Based on a subset of 11 multiply lensed systems with spectroscopic redshift, we produce a lens model that is accurate enough to secure new multiply lensed systems, totalling over a 100 a…
The Complete Ultraviolet Spectrum of the Archetypal "Wind-dominated" Quasar Mrk 231: Absorption and Emission from a High-speed Dusty Nuclear Outflow
Veilleux, S.; Rupke, D. S. N.; Hamann, F. +2 more
New near- and far-ultraviolet (NUV and FUV) Hubble Space Telescope spectra of Mrk 231, the nearest quasar known, are combined with ground-based optical spectra to study the remarkable dichotomy between the FUV and NUV-optical spectral regions in this object. The FUV emission-line features are faint, broad, and highly blueshifted (up to ∼7000 km s<…
Observation of a Quasiperiodic Pulsation in Hard X-Ray, Radio, and Extreme-ultraviolet Wavelengths
Kumar, Pankaj; Cho, Kyung-Suk; Nakariakov, Valery M.
We present a multiwavelength analysis of a quasiperiodic pulsation (QPP) observed in the hard X-ray (HXR), radio, and extreme-ultraviolet (EUV) channels during an M1.9 flare that occurred on 2011 September 23-24. The nonthermal HXR emission in 25-50 keV observed by RHESSI shows five distinct impulsive peaks of decaying amplitude with a period of a…
Nature, distribution, and origin of Titan's Undifferentiated Plains
Janssen, M. A.; Cassini RADAR Team; Lopes, Rosaly M. C. +15 more
The Undifferentiated Plains on Titan, first mapped by Lopes et al. (Lopes, R.M.C. et al., 2010. Icarus, 205, 540-588), are vast expanses of terrains that appear radar-dark and fairly uniform in Cassini Synthetic Aperture Radar (SAR) images. As a result, these terrains are often referred to as ;blandlands;. While the interpretation of several other…
The Search for Molecular Outflows in Local Volume AGNs with Herschel-PACS
Sturm, E.; Veilleux, S.; González-Alfonso, E. +3 more
We present the results from a systematic search for galactic-scale, molecular (OH 119 µm) outflows in a sample of 52 Local Volume (d\lt 50 Mpc) Burst Alert Telescope detected active galactic nuclei (BAT AGNs) with Herschel-PACS. We combine the results from our analysis of the BAT AGNs with the published Herschel/PACS data of 43 nearby (z\lt …
Cloud Structure of Galactic OB Cluster-forming Regions from Combining Ground- and Space-based Bolometric Observations
Li, Di; Qian, Lei; Rosolowsky, Erik +13 more
We have developed an iterative procedure to systematically combine the millimeter and submillimeter images of OB cluster-forming molecular clouds, which were taken by ground-based (CSO, JCMT, APEX, and IRAM-30 m) and space telescopes (Herschel and Planck). For the seven luminous (L\gt {10}6 L ⊙) Galactic OB cluster-forming mo…
Further ALMA observations and detailed modeling of the Red Rectangle
Sánchez Contreras, C.; Alcolea, J.; Santander-García, M. +3 more
Aims: We aim to study the rotating and expanding gas in the Red Rectangle, which is a well known bipolar nebula surrounding a double stellar system whose primary is a post-asymptotic giant branch (post-AGB) star. We analyze the properties of both components and the relation between them. Rotating disks have been very elusive in post-AGB nebul…
Composition, seasonal change, and bathymetry of Ligeia Mare, Titan, derived from its microwave thermal emission
Lorenz, R. D.; Karatekin, O.; Janssen, M. A. +8 more
For the last decade, the passive radiometer incorporated in the Cassini RADAR has recorded the 2.2 cm wavelength thermal emission from Titan's seas. In this paper, we analyze the radiometry observations collected from February 2007 to January 2015 over one of these seas, Ligeia Mare, with the goal of providing constraints on its composition, bathy…