Search Publications
Energetic Electron Acceleration in Unconfined Reconnection Jets
Xu, Y.; Zhang, Y.; Chen, G. +5 more
Magnetic reconnection in astronomical objects such as solar corona and the Earth’s magnetotail theoretically produces a fast jet toward the object (known as a confined jet as it connects to the object through magnetic field lines) and a fast jet departing the object (known as an unconfined jet as it propagates freely in space). So far, energetic e…
Impacts of EUV Wavefronts on Coronal Structures in Homologous Coronal Mass Ejections
Wang, Yuming; Shen, Chenglong; Liu, Rui +1 more
Large-scale propagating fronts are frequently observed during solar eruptions, yet whether or not they are waves is an open question, partly because the propagation is modulated by coronal structures, whose magnetic fields we still cannot measure. However, when a front impacts coronal structures, an opportunity arises for us to look into the magne…
High-resolution Near-infrared Spectroscopy of HD 100546. IV. Orbiting Companion Disappears on Schedule
Najita, Joan R.; Brittain, Sean D.; Carr, John S.
HD 100546 is a Herbig Ae/Be star surrounded by a disk with a large central region that is cleared of gas and dust (i.e., an inner hole). High-resolution near-infrared spectroscopy reveals a rich emission spectrum of fundamental rovibrational CO emission lines whose time variable properties point to the presence of an orbiting companion within the …
Stronger Constraints on the Evolution of the M BH-{\sigma }_{* } Relation up to z ∼ 0.6
Canalizo, Gabriela; Sexton, Remington O.; Treister, Ezequiel +4 more
We revisit the possibility of redshift evolution in the M BH-σ * relation with a sample of 22 Seyfert 1 galaxies with black holes (BHs) in the mass range {10}6.3{--}{10}8.3 {M}⊙ and redshift range 0.03 < z < 0.57 with spectra obtained from spatially resolved Keck/Low-resolution Imaging …
Unbiased Cosmological Parameter Estimation from Emission-line Surveys with Interlopers
Schneider, Donald P.; Gebhardt, Karl; Ciardullo, Robin +11 more
The galaxy catalogs generated from low-resolution emission-line surveys often contain both foreground and background interlopers due to line misidentification, which can bias the cosmological parameter estimation. In this paper, we present a method for correcting the interloper bias by using the joint analysis of auto- and cross-power spectra of t…
Different Signatures of Chromospheric Evaporation in Two Solar Flares Observed with IRIS
Gan, W. Q.; Ding, M. D.; Li, H. +2 more
We present different signatures of chromospheric evaporation in two solar flares observed by the Interface Region Imaging Spectrograph (IRIS). In the B1.6 flare on 2016 December 6 (SOL2016-12-06T10:40), the transition region Si IV line and the chromospheric C II and Mg II lines show blueshifts with low velocities up to 20 km s-1 at the …
CWISEP J193518.59-154620.3: An Extremely Cold Brown Dwarf in the Solar Neighborhood Discovered with CatWISE
Teplitz, Harry I.; Schlegel, David J.; Mobasher, Bahram +17 more
We present the discovery of an extremely cold, nearby brown dwarf in the solar neighborhood, found in the CatWISE catalog. Photometric follow-up with Spitzer reveals that the object, CWISEP J193518.59-154620.3, has ch1-ch2 = 3.24 ± 0.31 mag, making it one of the reddest brown dwarfs known. Using the Spitzer photometry and the polynomial relations …
A Confined Partial Eruption of Double-decker Filaments
Yang, Shuhong; Chen, Yao; Zheng, Ruisheng +6 more
Filament eruptions, one of the most energetic explosions on the Sun, release large quantities of magnetized plasma into the interplanetary space. Hence, the understanding of the initiation and evolution of filament eruptions can provide broader implications for space weather and geospace climate. Here, we present a confined partial eruption of dou…
The Most Massive Galaxies with Large Depleted Cores: Structural Parameter Relations and Black Hole Masses
Dullo, Bililign T.
Luminous spheroids (M V ≲ -21.50 ± 0.75 mag) contain partially depleted cores with sizes (R b) typically 0.02-0.5 kpc. However, galaxies with R b > 0.5 kpc are rare and poorly understood. Here, we perform detailed decompositions of the composite surface brightness profiles, extracted from archival Hubble Space…
Spatially Resolved Metal Loss from M31
Williams, Benjamin F.; Dalcanton, Julianne J.; Werk, Jessica K. +1 more
As galaxies evolve, they must enrich and exchange gas with the surrounding medium, but the timing of these processes and how much gas is involved remain poorly understood. In this work, we leverage metals as tracers of past gas flows to constrain the history of metal ejection and redistribution in M31. This roughly L* galaxy is a unique case where…