Search Publications
Galaxy Cluster Mass Estimates in the Presence of Substructure
Mateo, Mario; Olszewski, Edward W.; Miller, Christopher J. +3 more
We develop and implement a model to analyze the internal kinematics of galaxy clusters that may contain subpopulations of galaxies that do not independently trace the cluster potential. The model allows for substructures within the cluster environment and disentangles cluster members from contaminating foreground and background galaxies. We estima…
Inferring Contributions from Unresolved Point Sources to Diffuse Emissions Measured in UV Sky Surveys: General Method and SOHO/SWAN Case Study
Bzowski, M.; Kubiak, M. A.; Kowalska-Leszczynska, I. +1 more
In observations of diffuse emissions like, e.g., the Lyα heliospheric glow, contributions to the observed signal from point sources (e.g., stars) are considered to be a contamination. There are relatively few bright point sources that are usually properly resolved and can be subtracted or masked. We present results of an analysis of the distributi…
Termination Shock as a Source of Unusual Solar Radio Bursts
Chernov, Gennady; Fomichev, Valery
Using centimeter-wave and decimeter-wave solar radio spectral observations of the flares of 2003 November 18 and 2004 September 12, we have discussed two type-II-like bursts at the meter waves. The radio bursts show that the ordinary frequency drift from high to low frequencies slows down and stops, and a frequency drift from low to high frequenci…
The Energetic Thermonuclear Bursts in SAX J1712.6-3739
Lin, Jie; Yu, Wenfei
The neutron star low-mass X-ray binary SAX J1712.6-3739 is known for its long and hard thermonuclear X-ray bursts from previous observations. Its thermonuclear bursts are so distinct as they can last for tens of minutes, as seen with Swift/BAT (E > 15 keV). To explore the origin of these extreme bursts and the nature of SAX J1712.6-3739, we ana…
The Dynamics of the Magnetic-field-free Cavity around Comets
Nemeth, Z.
The diamagnetic cavity is the innermost region of the magnetosphere of an active comet, from which the magnetic field is expelled by the outflowing matter. This phenomenon, first detected around comet 1P/Halley, was extensively studied recently by the Rosetta comet chaser mission. Rosetta observed a surprisingly large diamagnetic cavity around com…
Localized Amplification of Magnetic Field in the Solar Photosphere Associated with a Rapid Moving Pore
Yang, Bo; Yang, Jiayan; Bi, Yi +4 more
In the Sun, the flows of hot plasma drive a dynamo that generates a global magnetic field as well as smaller-scale local fields. The existence of a magnetic field in turn affects the motion of plasma so that complex dynamic characteristics can be observed. In this Letter, we give an analysis on the localized amplification of magnetic fields in fro…
A Large Massive Quiescent Galaxy Sample at z ∼ 1.2
Sawicki, Marcin; Cheng, Cheng; Huang, Jia-Sheng +8 more
In this paper we present a simple color-magnitude selection and obtain a large sample of 33,893 massive quiescent galaxies at intermediate redshifts (1 < z < 1.5). We choose the longest wavelength available in the Hyper-Supreme-Cam (HSC) deep survey, the Y band and i - Y color, to select the 4000 Å Balmer jump in passive galaxies to the high…
Variability of the Great Disk Shadow in Serpens
Green, Joel D.; Pontoppidan, Klaus M.; Salyk, Colette +2 more
We present dual-epoch Hubble Space Telescope imaging of the great disk shadow in the Serpens star-forming region. The near-infrared images show strong variability of the disk shadow, revealing dynamics of the inner disk on timescales of months. The Great Shadow is projected onto the Serpens reflection nebula by an unresolved protoplanetary disk su…
A Detailed Analysis of the Cloud Structure and Dynamics in Aquila Rift
Nakamura, Fumitaka; Dobashi, Kazuhito; Shimoikura, Tomomi +1 more
We present maps in several molecular emission lines of a 1 square degree region covering the W40 and Serpens South molecular clouds belonging to the Aquila Rift complex. The observations were made with the 45 m telescope at the Nobeyama Radio Observatory. We found that the 12CO and 13CO emission lines consist of several veloc…
Softening of the Metagalactic Ionizing Background from Internal He II Absorption in Quasars
Shull, J. Michael; Danforth, Charles W.
Quasars and other active galactic nuclei (AGN) are significant contributors to the metagalactic ionizing background at redshifts z < 3. Recent Hubble Space Telescope (HST)/Cosmic Origins Spectrograph (COS) composite spectra of AGN find a harder flux distribution in the Lyman continuum, ${F}_{\nu }\propto {\nu }^{-{\alpha }_{s}}$ (αs …