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Compton-thick AGNs in the NuSTAR Era. II. A Deep NuSTAR and XMM-Newton View of the Candidate Compton-thick AGN in NGC 1358
Cusumano, G.; Vignali, C.; Ajello, M. +4 more
We present the combined NuSTAR and XMM-Newton 0.6-79 keV spectral analysis of a Seyfert 2 galaxy, NGC 1358, which we selected as a candidate Compton-thick (CT) active galactic nucleus (AGN) on the basis of previous Swift/BAT and Chandra studies. According to our analysis, NGC 1358 is confirmed to be a CT-AGN using physically motivated models, at &…
A Reanalysis of the Fundamental Parameters and Age of TRAPPIST-1
Gonzales, Eileen C.; McWilliam, Andrew; Teske, Johanna +3 more
We present the distance-calibrated spectral energy distribution (SED) of TRAPPIST-1 using a new medium-resolution (R ∼ 6000) near-infrared (NIR) Folded-port InfraRed Echellette (FIRE) spectrum and its Gaia parallax. We report an updated bolometric luminosity (L bol) of -3.216 ± 0.016, along with semiempirical fundamental parameters: eff…
Precision Distances to Dwarf Galaxies and Globular Clusters from Pan-STARRS1 3π RR Lyrae
Rix, Hans-Walter; Magnier, Eugene; Kudritzki, Rolf-Peter +6 more
We present new spatial models and distance estimates for globular clusters and dwarf spheroidals orbiting our Galaxy based on RR Lyrae (RRab) stars in the Pan-STARRS1 (PS1) 3π survey. Using the PS1 sample of RRab stars from Sesar et al. in 16 globular clusters and 5 dwarf galaxies, we fit structural models in (l, b, D) space; for 13 globular clust…
Measuring the Magnetic Field of Young Stars Using iSHELL Observations: BP Tau and V347 Aur
Flores, C.; Boogert, A.; Connelley, M. S. +1 more
While it has been suggested that there is a connection between the magnetic properties and the internal structure of young stars, there have not been enough magnetic measurements to firmly establish such a correlation at the earliest ages. Here, we contribute to this endeavor by presenting stellar parameters and magnetic field strength measurement…
Broadband Spectral Energy Distributions of SDSS-selected Quasars and of Their Host Galaxies: Intense Activity at the Onset of AGN Feedback
Lapi, Andrea; Gilli, Roberto; Baccigalupi, Carlo +3 more
We present the mean spectral energy distribution (SED) of a sample of optically selected quasars (QSOs) at redshifts of 1 ≤ z ≤ 5. To derive it, we exploit photometric information from the Sloan Digital Sky Survey, UKIRT Infrared Deep Sky Survey, and Wide-field Infrared Survey Explorer surveys in combination with a stacking analysis of Herschel, A…
Star Formation Histories of the LEGUS Spiral Galaxies. I. The Flocculent Spiral NGC 7793
Cignoni, M.; Tosi, M.; Sabbi, E. +13 more
We present a detailed study of the flocculent spiral galaxy NGC 7793, part of the Sculptor group. By analyzing the resolved stellar populations of the galaxy, located at a distance of ∼3.7 Mpc, we infer for the first time its radial star formation history (SFH) from Hubble Space Telescope photometry, thanks to both archival and new data from the L…
A Two-sided Loop X-Ray Solar Coronal Jet Driven by a Minifilament Eruption
Harra, Louise K.; Moore, Ronald L.; Sterling, Alphonse C. +1 more
Most of the commonly discussed solar coronal jets are the type that consist of a single spire extending approximately vertically from near the solar surface into the corona. Recent research supports that eruption of a miniature filament (minifilament) drives many such single-spire jets and concurrently generates a miniflare at the eruption site. A…
Joint X-Ray, EUV, and UV Observations of a Small Microflare
Krucker, Säm; White, Stephen M.; Grefenstette, Brian W. +5 more
We present the first joint observation of a small microflare in X-rays with the Nuclear Spectroscopic Telescope ARray (NuSTAR), in UV with the Interface Region Imaging Spectrograph (IRIS), and in EUV with the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA). These combined observations allow us to study the hot coronal and cooler …
Kinematics of the O VI Circumgalactic Medium: Halo Mass Dependence and Outflow Signatures
Charlton, Jane C.; Kacprzak, Glenn G.; Churchill, Christopher W. +4 more
We probe the high-ionization circumgalactic medium by examining absorber kinematics, absorber-galaxy kinematics, and average absorption profiles of 31 O VI absorbers from the “Multiphase Galaxy Halos” Survey as a function of halo mass, redshift, inclination, and azimuthal angle. The galaxies are isolated at 0.12 < z gal < 0.66 and…
Changes in Solar Rotation over Two Solar Cycles
Basu, Sarbani; Antia, H. M.
We use helioseismic data from ground- and space-based instruments to analyze how solar rotation has changed since the beginning of solar Cycle 23 with emphasis on studying the differences between Cycles 23 and 24. We find that the nature of solar rotation is indeed different for the two cycles. While the changes in the latitudinally independent co…