Search Publications
A new study of the spectroscopic binary 7 Vul with a Be star primary
Harmanec, P.; Labadie-Bartz, J.; Yang, S. +5 more
We confirmed the binary nature of the Be star 7 Vul, derived a more accurate spectroscopic orbit with an orbital period of 69.d4212±0.d0034, and improved the knowledge of the basic physical elements of the system. Analyzing available photometry and the strength of the Hα emission, we also document the lo…
Observations of GRO J1744-28 in quiescence with XMM-Newton
Tsygankov, S.; Santangelo, A.; Doroshenko, V. +3 more
We report on the deep observations of the "bursting pulsar" GRO J1744-28, which were performed with XMM-Newton and aimed to clarify the origin of its X-ray emission in quiescence. We detect the source at a luminosity level of ∼1034 erg s-1 with an X-ray spectrum that is consistent with the power law, blackbody, or accretion-h…
The impact of wind scalings on stellar growth and the baryon cycle in cosmological simulations
Kollmeier, Juna A.; Davé, Romeel; Weinberg, David H. +5 more
Many phenomenologically successful cosmological simulations employ kinetic winds to model galactic outflows. Yet systematic studies of how variations in kinetic wind scalings might alter observable galaxy properties are rare. Here we employ GADGET-3 simulations to study how the baryon cycle, stellar mass function, and other galaxy and CGM predicti…
AGN feedback in the FR II galaxy 3C 220.1
Jones, Christine; Nulsen, Paul E. J.; Forman, William R. +6 more
We present results from a deep (174 ks) Chandra observation of the FR-II radio galaxy 3C 220.1, the central brightest cluster galaxy (BCG) of a kT ∼ 4 keV cluster at z = 0.61. The temperature of the hot cluster medium drops from ∼5.9 to ∼3.9 keV at ∼35 kpc radius, while the temperature at smaller radii may be substantially lower. The central activ…
Spatial Distribution of the Origin of Umbral Waves in a Sunspot Umbra
Kilcik, Ali; Yurchyshyn, Vasyl; Lim, Eun-Kyung +2 more
Umbral flashes (UFs) are emissions in the core of chromospheric lines caused by upward propagating waves steepening into shocks. UFs are followed by an expanding blueshifted umbral wave and redshifted plasma returning to the initial state. Here we use 5 s cadence images acquired at ±0.04 nm off the H ${}_{\alpha }$ line center by the Visible Imagi…
A two-sided but significantly beamed jet in the supercritical accretion quasar IRAS F11119+3257
Paragi, Zsolt; Yang, Jun; An, Tao +3 more
Highly accreting quasars are quite luminous in the X-ray and optical regimes; while, they tend to become radio quiet and have optically thin radio spectra. Among the known quasars, IRAS F11119+3257 is a supercritical accretion source because it has a bolometric luminosity slightly above the Eddington limit and extremely powerful X-ray outflows. To…
Discovery of Two Nearby Post-T Tauri Stellar Associations
Fang, Min; Liu, Chao; Liu, Jiaming
In this work we report the discovery of two new stellar associations in close vicinity of the Sun at roughly 180 and 150 pc. These two associations, u Tau assoc and e Tau assoc, were detected based on their clustering in a multi-dimensional parameter space including α, δ, µα, µδ, and ϖ of Gaia. The fitting of pre-…
Deciphering the nature of the pulsar wind nebula CTB 87 with XMM-Newton
Safi-Harb, S.; Kothes, R.; Bucciantini, N. +5 more
CTB 87 (G74.9+1.2) is an evolved supernova remnant (SNR) which hosts a peculiar pulsar wind nebula (PWN). The X-ray peak is offset from that observed in radio and lies towards the edge of the radio nebula. The putative pulsar, CXOU J201609.2+371110, was first resolved with Chandra and is surrounded by a compact and a more extended X-ray nebula. He…
Asymptotic kinematics of globular clusters: The emergence of a Tully-Fisher relation
Hernandez, X.; Lara-D I, A. J.
Using a recent homogeneous sample of 40 high-quality velocity dispersion profiles for Galactic globular clusters, we study the regime of low gravitational acceleration relevant to the outskirts of these systems. We find that a simple empirical profile having a central Gaussian component and a constant large-radius asymptote, σ∞, accurat…
Interpreting Observations of Absorption Lines in the Circumgalactic Medium with a Turbulent Medium
Fumagalli, Michele; Buie, Edward, II; Scannapieco, Evan
Single-phase photoionization equilibrium (PIE) models are often used to infer the underlying physical properties of galaxy halos probed in absorption with ions at different ionization potentials. To incorporate the effects of turbulence, we use the Models of Agitated and Illuminated Hindering and Emitting Media (MAIHEM) code to model an isotropic …