Search Publications
Orbit-based Dynamical Models of the Sombrero Galaxy (NGC 4594)
Gebhardt, Karl; Richstone, Douglas; Kormendy, John +6 more
We present axisymmetric, orbit-based models to study the central black hole (BH), stellar mass-to-light ratio (M/L), and dark matter (DM) halo of NGC 4594 (M104, the Sombrero Galaxy). For stellar kinematics, we use published high-resolution kinematics of the central region taken with the Hubble Space Telescope, newly obtained Gemini long-slit spec…
Discovery of a Cyclotron Resonance Feature in the X-Ray Spectrum of GX 304-1 with RXTE and Suzaku during Outbursts Detected by MAXI in 2010
Yamaoka, Kazutaka; Makishima, Kazuo; Mihara, Tatehiro +5 more
We report on the discovery of a cyclotron resonance scattering feature (CRSF) in the X-ray spectrum of GX 304
Mid-IR, Far-IR, Raman micro-spectroscopy, and FESEM-EDX study of IDP L2021C5: Clues to its origin
Rotundi, A.; Dartois, E.; Brunetto, R. +8 more
Interplanetary Dust Particles (IDPs) are potentially of cometary origin. They may therefore provide important clues to a better understanding of the early Solar System physical and chemical conditions. A chondritic porous aggregate IDP (named L2021C5) was analyzed using mid to far FTIR (2-60 µm) micro-spectroscopy, Raman micro-spectroscopy, …
Unique spinel-rich lithology in lunar meteorite ALHA 81005: Origin and possible connection to M3 observations of the farside highlands
Treiman, Allan H.; Gross, Juliane
A new lunar rock type, rich in (Mg, Fe)Al spinel and lacking abundant olivine and pyroxene, was recently detected by near-infrared reflectance spectroscopy by the M3 instrument on the Chandrayaan-1 spacecraft. No such material has been described from lunar rocks, either returned samples or meteorites. Here we describe a fragment of rock…
Optical Polarization Mapping Toward the Interface Between the Local Cavity and Loop I
Santos, Fábio P.; Corradi, Wagner; Reis, Wilson
The Sun is located inside an extremely low density and quite irregular volume of the interstellar medium, known as the Local Cavity (LC). It has been widely believed that some kind of interaction could be occurring between the LC and Loop I, a nearby superbubble seen in the direction of the Galactic center. As a result of such interaction, a wall …
Molecular gas in submillimetre-faint, star-forming ultraluminous galaxies at z > 1
Muxlow, T. W. B.; Smail, I.; Genzel, R. +12 more
We present interferometric CO observations of 12 z∼ 2 submillimetre-faint, star-forming radio galaxies (SFRGs) which are thought to be ultraluminous infrared galaxies (ULIRGs) possibly dominated by warmer dust (Tdust ≳ 40 K) than submillimetre galaxies (SMGs) of similar luminosities. Four other CO-observed SFRGs are included from the li…
Uncovering Obscured Active Galactic Nuclei in Homogeneously Selected Samples of Seyfert 2 Galaxies
Ptak, A.; Sonnentrucker, P.; Heckman, T. M. +4 more
We have analyzed archival Chandra and XMM-Newton data for two nearly complete homogeneously selected samples of type 2 Seyfert galaxies (Sy2s). These samples were selected based on intrinsic active galactic nuclei (AGNs) flux proxies: a mid-infrared (MIR) sample from the original IRAS 12 µm survey and an optical ([O III]λ 5007 flux limited) …
Cosmic Origins Spectrograph Detection of Ne VIII Tracing Warm-Hot Gas Toward PKS 0405-123
Sembach, Kenneth R.; Savage, Blair D.; Shull, J. Michael +7 more
We report on the detection of Ne VIII in the Hubble Space Telescope/Cosmic Origins Spectrograph (COS) spectrum of the intervening absorption system at z = 0.495096 toward PKS 0405-123 (z em = 0.5726). The high signal-to-noise COS spectrum also covers absorption from H I, C III, O III, O IV, and O VI associated with this multiphase syste…
Proton acceleration in antiparallel collisionless magnetic reconnection: Kinetic mechanisms behind the fluid dynamics
Belmont, G.; Aunai, N.; Smets, R.
This paper investigates the proton kinetic mechanisms leading to the formation of plasma jets in antiparallel magnetic reconnection. In particular, the interaction of the protons with the Hall electric field in the proton non-ideal region is discussed. The study, based on a two-dimensional hybrid simulation, details the important role of the proto…
High kinetic energy density jets in the Earth’s magnetosheath: A case study
Amata, E.; Bogdanova, Y. V.; Marcucci, M. F. +4 more
We study several high kinetic energy density jets observed during a traversal of the dayside magnetosheath by the Cluster spacecraft on March 17, 2001, at various distances from the magnetopause, generally characterised by anomalously high values of the local magnetosonic Mach number. We concentrate on two jets observed just outside the magnetopau…