Search Publications
A Long-duration Superflare on the K Giant HD 251108
Schmitt, J. H. M. M.; Notsu, Yuta; Maehara, Hiroyuki +10 more
Many giant stars are magnetically active, which causes rotational variability, chromospheric emission lines, and X-ray emission. Large outbursts in these emission features can set limits on the magnetic field strength and thus constrain the mechanism of the underlying dynamo. HD 251108 is a Li-rich active K-type giant. We find a rotational period …
Time Series of Magnetic Field Parameters of Merged MDI and HMI Space-weather Active Region Patches as Potential Tool for Solar Flare Forecasting
Kosovichev, Alexander G.; Nita, Gelu M.; Sadykov, Viacheslav M. +8 more
Solar flare prediction studies have been recently conducted with the use of Space-Weather MDI (Michelson Doppler Imager on board Solar and Heliospheric Observatory) Active Region Patches (SMARPs) and Space-Weather HMI (Helioseismic and Magnetic Imager on board Solar Dynamics Observatory) Active Region Patches (SHARPs), which are two currently avai…
Time-resolved Hubble Space Telescope Wide Field Camera 3 Spectrophotometry Reveals Inefficient Day-to-night Heat Redistribution in the Highly Irradiated Brown Dwarf SDSS 1557B
Mayorga, L. C.; Lothringer, Joshua D.; Apai, Dániel +8 more
Brown dwarfs (BDs) in ultra-short-period orbits around white dwarfs (WDs) offer a unique opportunity to study the properties of tidally locked, fast-rotating (1–3 hr), and highly irradiated atmospheres. Here we present phase-resolved spectrophotometry of the WD–BD binary SDSS 1557, which is the fifth WD–BD binary in our six-object sample. Using th…
An Extremely Young Protostellar Core, MMS 1/OMC-3: Episodic Mass Ejection History Traced by the Micro SiO Jet
Herczeg, Gregory J.; Johnstone, Doug; Mairs, Steve +11 more
We present ∼0.″2 (∼80 au) resolution observations of the CO(2–1) and SiO(5–4) lines made with the Atacama large millimeter/submillimeter array toward an extremely young intermediate-mass protostellar source (t dyn < 1000 yr), MMS 1 located in the Orion Molecular Cloud-3 region. We have successfully imaged a very compact CO molecular …
On the Connection between the Repeated X-Ray Quasiperiodic Oscillation and Warm Absorber in the Active Galaxy RE J1034+396
Nicastro, Fabrizio; Mao, Junjie; Wang, Yijun +3 more
We conduct an in-depth spectral analysis of ∼1 Ms XMM-Newton data of the narrow line Seyfert 1 galaxy RE J1034+396. The long exposure ensures high spectral quality and provides us with a detailed look at the intrinsic absorption and emission features toward this target. Two warm-absorber (WA) components with different ionization states ( $\mathrm{…
The FENIKS Survey: Multiwavelength Photometric Catalog in the UDS Field, and Catalogs of Photometric Redshifts and Stellar Population Properties
Papovich, Casey; Muzzin, Adam; Glazebrook, Karl +11 more
We present the construction of a deep multiwavelength point-spread-function-matched photometric catalog in the Ultra-Deep Survey (UDS) field following the final UKIDSS UDS release. The catalog includes photometry in 24 filters, from the MegaCam-uS 0.38 µm band to the Spitzer-IRAC 8 µm band, over ∼0.9 deg2 and with a 5σ depth…
Morphology of Molecular Clouds at Kiloparsec Scale in the Milky Way: Shear-induced Alignment and Vertical Confinement
Li, Guang-Xing; Chen, Bing-Qiu; Xie, Yi-Heng
The shape of the cold interstellar molecular gas is determined by several processes, including self-gravity, tidal force, turbulence, magnetic field, and galactic shear. Based on the 3D dust extinction map derived by Vergely et al., we identify a sample of 550 molecular clouds within 3 kpc of the solar vicinity in the Galactic disk. Our sample con…
Three-stage Acceleration of Solar Energetic Particles Detected by Parker Solar Probe
Li, Chuan; Chen, Xiaomin
Coronal mass ejections (CMEs) drive powerful shocks and thereby accelerate solar energetic particles (SEPs) as they propagate from the corona into interplanetary space. Here we present the processes of three-stage particle acceleration by a CME-driven shock detected by the in situ spacecraft—Parker Solar Probe (PSP) on 2022 August 27. The onset of…
XMM-Newton High-resolution Spectroscopy of EXO 0748–676 after Its Reemergence from a Long Quiescence
Bhattacharya, Sayantan; Bhattacharyya, Sudip; Shaw, Gargi
EXO 0748–676 is a well-studied, high-inclination, dipping and eclipsing neutron star low-mass X-ray binary that has recently emerged from 16 yr of quiescence into a new outburst. We present results from 55.5 ks of XMM-Newton observation, focusing on high-resolution spectroscopy with the same instrument (the Reflection Grating Spectrometer) that pr…
Stripe 82-XL: The ∼54.8 deg2 and ∼18.8 Ms Chandra and XMM-Newton Point-source Catalog and Number of Counts
Marchesi, Stefano; LaMassa, Stephanie; Urry, C. Megan +9 more
We present an enhanced version of the publicly available Stripe 82X catalog (S82-XL), featuring a comprehensive set of 22,737 unique X-ray point sources identified with a significance ≳4σ. This catalog is four times larger than the original Stripe 82X catalog, by including additional archival data from the Chandra and XMM-Newton telescopes. Now co…