Search Publications
Predicting the Arrival Time of an Interplanetary Shock Based on DSRT Spectrum Observations for the Corresponding Type II Radio Burst and a Blast Wave Theory
Feng, Shiwei; Ruan, Mengsi; Li, Ran +7 more
Since fast head-on coronal mass ejections and their associated shocks represent potential hazards to the space environment of the Earth and even other planets, forecasting the arrival time of the corresponding interplanetary shock is a priority in space weather research and prediction. Based on the radio spectrum observations of the 16-element arr…
The Empirical and Radiative Transfer Hybrid (EaRTH) Disk Model: Merging Analyses of Protoplanetary Dust Disk Mineralogy and Structure
Stassun, Keivan G.; Pinte, Christophe; Principe, David A. +7 more
Our understanding of how exoplanets form and evolve relies on analyses of both the mineralogy of protoplanetary disks and their detailed structures; however, these key complementary aspects of disks are usually studied separately. We present initial results from a hybrid model that combines the empirical characterization of the mineralogy of a dis…
The Age Distribution of Stellar Orbit Space Clumps
Rix, Hans-Walter; Fürnkranz, Verena; Coronado, Johanna +1 more
The orbit distribution of young stars in the Galactic disk is highly structured, from well-defined clusters to streams of stars that may be widely dispersed across the sky, but are compact in orbital action-angle space. The age distribution of such groups can constrain the timescales over which conatal groups of stars disperse into the "field." Ga…
Detection of Extragalactic Anomalous Microwave Emission in NGC 2903 Using KVN Single-dish Observations
Tsai, Chao-Wei; Hoang, Thiem; Nakanishi, Hiroyuki +4 more
We present the results of the single-dish observations using the Korean VLBI Network to search for anomalous microwave emission (AME) in nearby galaxies. The targets were selected from 'Mapping the dense molecular gas in the strongest star-forming galaxies' (MALATANG), a legacy survey project of the James Clerk Maxwell Telescope. The MALATANG gala…
Origin and Properties of the Near-subsonic Solar Wind Observed by Parker Solar Probe
Liu, Ying D.; Kasper, Justin C.; Stevens, Michael L. +3 more
We identify and examine the solar wind intervals near the sonic critical point (i.e., M S ∼ 1) observed by the Parker Solar Probe. The near-subsonic wind intervals show similar properties: a low density, an extremely low velocity, a low proton temperature, and essentially no magnetic field deflections compared with the surrounding sol…
Merger-driven Growth of Intermediate-mass Black Holes: Constraints from Hubble Space Telescope Imaging of Hyper-luminous X-Ray Sources
Stern, Daniel; Comerford, Julia M.; Barrows, R. Scott +1 more
Hyper-luminous X-ray sources (HLXs) are extragalactic off-nuclear X-ray sources with luminosities exceeding the theoretical limit for accretion onto stellar-mass compact objects. Many HLXs may represent intermediate-mass black holes (IMBHs) deposited in galaxy halos through mergers, and the properties of the stellar cores surrounding HLXs provide …
Revision of the GeV γ-Ray Emission in the Region of HESS J1813-178 with Fermi-LAT
Xin, Yuliang; Guo, Xiaolei
HESS J1813-178 is one of the brightest and most compact TeV γ-ray sources, and whether its γ-ray emission is associated with supernova remnant (SNR), pulsar wind nebula (PWN), or young stellar cluster (YSC) is still under debate. By analyzing the GeV γ-ray data in the field of HESS J1813-178 using 14 yr of PASS 8 data recorded by the Fermi Large A…
Volatile-rich Sub-Neptunes as Hydrothermal Worlds: The Case of K2-18 b
Fortney, Jonathan J.; Moses, Julianne I.; Zhang, Xi +8 more
Temperate exoplanets between the sizes of Earth and Neptune, known as "sub-Neptunes," have emerged as intriguing targets for astrobiology. It is unknown whether these planets resemble Earth-like terrestrial worlds with a habitable surface, Neptune-like giant planets with deep atmospheres and no habitable surface, or something exotic in between. Re…
Dual-band Observations of the Asymmetric Ring around CIDA 9A: Dead or Alive?
Herczeg, Gregory J.; Johnstone, Doug; Long, Feng +9 more
While the most exciting explanation of the observed dust asymmetries in protoplanetary disks is the presence of protoplanets, other mechanisms can also form the dust features. This paper presents dual-wavelength Atacama Large Millimeter/submillimeter Array observations of a large asymmetric dusty ring around the M-type star CIDA 9A. We detect a du…
Calibrating and Standardizing the Tip of the Red Giant Branch in the Small Magellanic Cloud Using Small-amplitude Red Giants
Anderson, Richard I.; Koblischke, Nolan W.
We investigate the absolute calibration of the tip of the red giant branch (TRGB) in the Small Magellanic Cloud (SMC) using small amplitude red giant stars (SARGs) classified by the Optical Gravitational Lensing Experiment (OGLE). We show that all stars near the SMC's TRGB are SARGs. Distinguishing older and younger RGs near the tip according to t…