Search Publications
Proper Motions and Structural Parameters of the Galactic Globular Cluster M71
Dalessandro, E.; Massari, D.; Ferraro, F. R. +4 more
By exploiting two ACS/HST data sets separated by a temporal baseline of ∼7 years, we have determined the relative stellar proper motions (PMs; providing membership) and the absolute PM of the Galactic globular cluster M71. The absolute PM has been used to reconstruct the cluster orbit within a Galactic, three-component, axisymmetric potential. M71…
Lyα Absorbers and the Coma Cluster
Yoon, Joo Heon; Putman, M. E.
The spatial and kinematic distribution of warm gas in and around the Coma Cluster is presented through observations of Lyα absorbers using background QSOs. Updates to the Lyα absorber distribution found in Yoon et al. for the Virgo Cluster are also presented. At 0.2-2.0R vir of Coma we identify 14 Lyα absorbers ({N}{{H}{{I}}}…
Individual, Model-independent Masses of the Closest Known Brown Dwarf Binary to the Sun
Lu, Jessica R.; Kalas, Paul; De Rosa, Robert J. +18 more
At a distance of ∼2 pc, our nearest brown dwarf neighbor, Luhman 16 AB, has been extensively studied since its discovery 3 years ago, yet its most fundamental parameter—the masses of the individual dwarfs—has not been constrained with precision. In this work, we present the full astrometric orbit and barycentric motion of Luhman 16 AB and the firs…
Discovery of a Satellite of the Large Trans-Neptunian Object (225088) 2007 OR10
Pál, András; Vinkó, József; Marton, Gábor +6 more
2007 OR10 is currently the third largest known dwarf planet in the trans-Neptunian region, with an effective radiometric diameter of ∼1535 km. It has a slow rotation period of ∼45 hr that was suspected to be caused by tidal interactions with a satellite undetected at that time. Here, we report on the discovery of a likely moon of 2007 O…
Tycho-Gaia Astrometric Solution Parallaxes and Proper Motions for Five Galactic Globular Clusters
van der Marel, Roeland P.; Watkins, Laura L.
We present a pilot study of Galactic globular cluster (GC) proper motion (PM) determinations using Gaia data. We search for GC stars in the Tycho-Gaia Astrometric Solution (TGAS) catalog from Gaia Data Release 1 (DR1), and identify five members of NGC 104 (47 Tucanae), one member of NGC 5272 (M3), five members of NGC 6121 (M4), seven members of NG…
Toward the Understanding of the Physical Origin of Recombining Plasma in the Supernova Remnant IC 443
Uchida, Hiroyuki; Tsuru, Takeshi Go; Tanaka, Takaaki +2 more
We perform a spatially resolved spectroscopic analysis of X-ray emission from the supernova remnant (SNR) IC 443 with Suzaku. All of the spectra are well reproduced by a model consisting of a collisional ionization equilibrium (CIE) and two recombining plasma (RP) components. Although previous X-ray studies found an RP in the northeastern region, …
Evolution of Spin, Orbital, and Superorbital Modulations of 4U 0114+650
Hu, Chin-Ping; Chou, Yi; Ng, C. -Y. +2 more
We report a systematic analysis of the spin, orbital, and superorbital modulations of 4U 0114+650, a high-mass X-ray binary that consists of one of the slowest spinning neutron stars. Using the dynamic power spectrum, we found that the spin period varied dramatically and is anticorrelated with the long-term X-ray flux variation that can be observe…
Mode Conversion of a Solar Extreme-ultraviolet Wave over a Coronal Cavity
Dai, Yu; Zong, Weiguo
We report on observations of an extreme-ultraviolet (EUV) wave event in the Sun on 2011 January 13 by Solar Terrestrial Relations Observatory and Solar Dynamics Observatory in quadrature. Both the trailing edge and the leading edge of the EUV wave front in the north direction are reliably traced, revealing generally compatible propagation velociti…
A Sun-to-Earth Analysis of Magnetic Helicity of the 2013 March 17-18 Interplanetary Coronal Mass Ejection
Gopalswamy, Nat; Akiyama, Sachiko; Yashiro, Seiji +4 more
We compare the magnetic helicity in the 2013 March 17-18 interplanetary coronal mass ejection (ICME) flux rope at 1 au and in its solar counterpart. The progenitor coronal mass ejection (CME) erupted on 2013 March 15 from NOAA active region 11692 and is associated with an M1.1 flare. We derive the source region reconnection flux using the post-eru…
Central Engine and Host Galaxy of RXJ 1301.9+2747: A Multiwavelength View of a Low-mass Black Hole Active Galactic Nuclei with Ultra-soft X-Ray Emission
Shu, X. W.; Wang, J. X.; Wang, T. G. +3 more
RXJ 1301.9+2747 is an optically identified very-low-mass AGN candidate with {M}{BH}∼ 1× {10}6 {M}⊙ , which shows extremely soft X-ray emission and unusual X-ray variability in the form of short-lived flares. We present an analysis of multiwavelength observations of RXJ 1301.9+2747 in order to study the properties o…