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Optical and Near-infrared Observations of the Distant but Bright "New Year's Burst" GRB 220101A
Fynbo, Johan P. U.; Gao, Xing; Xu, Dong +26 more
High-redshift gamma-ray bursts (GRBs) are useful to probe the early Universe, but only a few candidates have been detected so far. Here, we report the optical and near-infrared observations of the afterglow of a relatively high-redshift event GRB 220101A, which was triggered on New Year's Day of 2022, and therefore referred to as the "New Year's b…
Andromeda's Parachute: Time Delays and Hubble Constant
Dahle, Håkon; Goicoechea, Luis J.; Shalyapin, Vyacheslav N. +1 more
The gravitational lens system PS J0147+4630 (Andromeda's Parachute) consists of four quasar images ABCD and a lensing galaxy. We obtained r-band light curves of ABCD in the 2017-2022 period from monitoring with two 2 m class telescopes. Applying state-of-the-art curve-shifting algorithms to these light curves led to measurements of time delays bet…
Dynamical Response of Solar Wind Charge Exchange Soft X-Ray Emission in Earth's Magnetosphere to the Solar Wind Proton Flux
Ji, Li; Wang, Chi; Liu, Wenhao +5 more
This work studies the dynamic response of solar wind charge exchange (SWCX) soft X-ray emission in the Earth's magnetosphere to the solar wind proton flux. Unlike previous studies that attempted to use complex magnetohydrodynamic models to match the details of observed SWCX of a necessarily limited number of cases, this work focuses on determining…
ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): The Warm-envelope Origin of Hot Corinos
Sanhueza, Patricio; Kwon, Woojin; Chen, Huei-Ru Vivien +24 more
Hot corinos are of great interest due to their richness in interstellar complex organic molecules (COMs) and the consequent potential prebiotic connection to solar-like planetary systems. Recent surveys have reported an increasing number of detected hot corinos in Class 0/I protostars; however, the relationships between their physical properties a…
Influence of Intermittency on the Energy Transfer Rate of Solar Wind Turbulence
Wang, Xin; Yuan, Zhigang; Huang, Shiyong +2 more
The intermittency in the solar wind turbulence manifests itself in the anisotropic scaling due to the anisotropic spectral index and the intermittent level based on the extended P model. However, the influence of intermittency on the energy transfer rate remains unclear. Here we apply the partial variance of increments method to identify the inter…
Third Epoch HST Imaging of a Nonradiative Shock in the Cygnus Loop Supernova Remnant
Blair, William P.; Raymond, John C.; Sankrit, Ravi
We present new HST/WFC3 optical images of a region in the northeastern part of the Cygnus Loop supernova remnant, which includes a well-studied Balmer-line filament. These data represent the third epoch of HST Hα imaging and a second epoch of [O III] λ5007 imaging of that particular filament. The Hα images were used to measure the proper motions a…
Interpretation of Flat Energy Spectra Upstream of Fast Interplanetary Shocks
Zimbardo, Gaetano; Servidio, Sergio; Wilson, Lynn B., III +6 more
Interplanetary shocks are large-scale heliospheric structures often caused by eruptive phenomena at the Sun, and represent one of the main sources of energetic particles. Several interplanetary (IP) shock crossings by spacecraft at 1 au have revealed enhanced energetic-ion fluxes that extend far upstream of the shock. Surprisingly, in some shock e…
The Messy Nature of Fiber Spectra: Star-Quasar Pairs Masquerading as Dual Type 1 AGNs
Bohn, Thomas; Pfeifle, Ryan W.; Secrest, Nathan J. +5 more
Theoretical studies predict that the most significant growth of supermassive black holes (SMBHs) occurs in late-stage mergers, coinciding with the manifestation of dual active galactic nuclei (AGNs), and both major and minor mergers are expected to be important for dual AGN growth. In fact, dual AGNs in minor mergers should be signposts for effici…
Splitting and Reconstruction of a Solar Filament Caused by Magnetic Emergence and Reconnection
Xu, Zhe; Xue, Zhike; Yan, Xiaoli +4 more
We present observations and interpretation of a nonerupting filament in NOAA active region (AR) 12827 that undergoes splitting and restructuring on 2021 June 4, using the high-resolution data obtained by the New Vacuum Solar Telescope, the Solar Dynamics Observatory, and the Interface Region Imaging Spectrograph. At the beginning, the right footpo…
A Broadband X-Ray Study of the Dwarf Nova SS Cyg during Quiescence and Outburst
Mukai, Koji; Dutta, Anirban; Rana, Vikram +1 more
We present a broadband X-ray study (~0.3-50 keV) of the dwarf nova SS Cyg highlighting the changes in the accretion during two phases, the quiescence and the outburst states. The investigation was based on simultaneous observations carried out with the XMM-Newton and NuSTAR telescopes in two epochs, involving medium- and high-resolution spectrosco…