Search Publications
A New Tool for Understanding the Solar Wind-Venus Interaction: Three-dimensional Multifluid MHD Model
Zhang, Tielong; Yao, Zhonghua; Dang, Tong +5 more
In this paper, we present a new tool to investigate the interaction of the solar wind with Venus with the approach of a global multifluid magnetohydrodynamics (MHD) model. The continuity, momentum, and energy equations for H+, O+, ${{\rm{O}}}_{2}^{+}$ , and ${\mathrm{CO}}_{2}^{+}$ are solved self-consistently together with Fa…
Sequential Remote Brightenings and Co-spatial Fast Downflows during Two Successive Flares
Cheng, X.; Ding, M. D.; Li, C. +2 more
Remote brightenings often appear at the outskirts of the active regions of solar eruptive events. Nevertheless, their origin remains to be ascertained. In this study, we report imaging and spectroscopic observations of sequential remote brightenings with a combination of observations from the Hα Imaging Spectrograph on board the Chinese Hα Solar E…
The Transition Region of Solar Flare Loops
Antiochos, Spiro K.; Young, Peter R.; Gontikakis, Costis
The transition region between the Sun's corona and chromosphere is important to the mass and energy transfer from the lower atmosphere to the corona; consequently, this region has been studied intensely with ultraviolet and extreme ultraviolet (EUV) observations. A major result of these studies is that the amount of plasma at low temperatures, <…
Investigating the Superorbital Modulations in 4U 1909 + 07, IGR J16418-4532, and IGR J16479-4514 with Swift XRT, BAT, and NuSTAR Observations
Pottschmidt, Katja; Corbet, Robin H. D.; Coley, Joel B. +2 more
A puzzling variety of superorbital modulations has been discovered in several supergiant high mass X-ray binaries (sgHMXBs). To investigate the mechanisms driving these superorbital modulations, we have analyzed long-term Neil Gehrels Swift Observatory (Swift) Burst Alert Telescope (BAT) observations of three sgHMXBs: 4U 1909 + 07, IGR J16418-4532…
Imaging of HH80-81 Jet in the Near-infrared Shock Tracers H2 and [Fe II]
Vig, S.; Tej, A.; Mohan, Sreelekshmi +1 more
The HH80-81 system is one of the most powerful jets driven by a massive protostar. We present new near-infrared (NIR) line imaging observations of the HH80-81 jet in the H2 (2.122 µm) and [Fe II] (1.644 µm) lines. These lines trace not only the jet close to the exciting source but also the knots located farther away. We have…
Asteroseismology of the Pulsating Extremely Low-mass White Dwarf SDSS J111215.82 + 111745.0: A Model with p-mode Pulsations Consistent with the Observations
Su, Jie; Li, Yan
SDSS J111215.82+111745.0 is the second pulsating extremely low-mass white dwarf discovered. Two short-period pulsations, 107.56 and 134.275 s, were detected on this star, which would be the first observed pressure mode (p-mode) pulsations observed on a white dwarf. While the two potential p-modes have yet to be confirmed, they make SDSS J111215.82…
Coronal Abundances in an Active Region: Evolution and Underlying Chromospheric and Transition Region Properties
Testa, Paola; Martínez-Sykora, Juan; De Pontieu, Bart
The element abundances in the solar corona and solar wind are often different from those of the solar photosphere, typically with a relative enrichment of elements with low first ionization potential (FIP effect). Here, we study the spatial distribution and temporal evolution of the coronal chemical composition in an active region (AR) over about …
Dependence of Stellar Differential Rotation on Effective Temperature and Rotation: An Analysis from Starspot Transit Mapping
Valio, Adriana; Araújo, Alexandre
Stellar rotation is crucial for studying stellar evolution, since it provides information about age, angular momentum transfer, and magnetic fields of stars. In the case of the Sun, due to its proximity, detailed observation of sunspots at various latitudes and longitudes allows a precise estimation of the solar rotation period and its differentia…
Asteroseismology Sheds Light on the Origin of Carbon-deficient Red Giants: Likely Merger Products and Linked to the Li-rich Giants
Zhao, Gang; Campbell, Simon W.; Reddy, Bacham E. +2 more
Carbon-deficient red giants (CDGs) are a peculiar class of stars that have eluded explanation for decades. We aim to better characterize CDGs by using asteroseismology (Kepler, TESS) combined with spectroscopy (APOGEE, LAMOST), and astrometry (Gaia). We discovered 15 new CDGs in the Kepler field, and confirm that CDGs are rare, as they are only 0.…
Properties of Star Formation of the Large Magellanic Cloud As Probed by Young Stellar Objects
Tachihara, Kengo; Kaneda, Hidehiro; Fukui, Yasuo +2 more
We perform a systematic study of the evolutionary stages and stellar masses of young stellar objects (YSOs) in the Large Magellanic Cloud (LMC) to investigate the properties of star formation in the galaxy. There are 4825 sources in our YSO sample, which are constructed by combining the previous studies identifying YSOs in the LMC. Spectral energy…