Search Publications

Testing the Fidelity of Simulations of Black Hole-Galaxy Coevolution at z ∼ 1.5 with Observations
DOI: 10.3847/1538-4357/ab91be Bibcode: 2020ApJ...896..159D

Treu, Tommaso; Bhowmick, Aklant K.; Menci, N. +3 more

We examine the scaling relations between the mass of a supermassive black hole (SMBH) and its host galaxy properties at 1.2 < z <1.7 using both observational data and simulations. Recent measurements of 32 X-ray-selected, broad-line active galactic nuclei (AGNs) are compared with two independent state-of-the-art efforts, including the hydrod…

2020 The Astrophysical Journal
eHST 9
Mapping Circumstellar Magnetic Fields of Late-type Evolved Stars with the Goldreich-Kylafis Effect: CARMA Observations at λ1.3 mm of R Crt and R Leo
DOI: 10.3847/1538-4357/aba122 Bibcode: 2020ApJ...899..152H

Lai, Shih-Ping; Agudo, Iván; Vlemmings, Wouter H. T. +3 more

Mapping magnetic fields is the key to resolving the unclear physical picture of circumstellar magnetic fields in late-type evolved stars. Observations of linearly polarized emission from thermal molecular line transitions due to the Goldreich-Kylafis (G-K) effect provide valuable insights into the magnetic field geometry in these sources that are …

2020 The Astrophysical Journal
Gaia 9
Velocity Response of the Observed Explosive Events in the Lower Solar Atmosphere. I. Formation of the Flowing Cool-loop System
DOI: 10.3847/1538-4357/ab86bb Bibcode: 2020ApJ...894..155S

Tiwari, Sanjiv K.; Srivastava, A. K.; Konkol, P. +6 more

We observe plasma flows in cool loops using the Slit-Jaw Imager on board the Interface Region Imaging Spectrometer (IRIS). Huang et al. observed unusually broadened Si IV 1403 Šline profiles at the footpoints of such loops that were attributed to signatures of explosive events (EEs). We have chosen one such unidirectional flowing cool-loop system …

2020 The Astrophysical Journal
IRIS 9
Gemini Multi-Object Spectrograph Integral Field Unit Spectroscopy of the Double-peaked Broad Emission Line of a Red Active Galactic Nucleus
DOI: 10.3847/1538-4357/ab86a4 Bibcode: 2020ApJ...894..126K

Ho, Luis C.; Im, Myungshin; Kim, Minjin +1 more

Galaxy mergers are expected to produce multiple supermassive black holes (SMBHs) in close-separation, but the detection of such SMBHs has been difficult. 2MASS J165939.7 + 183436 is a red active galactic nucleus (AGN) that is a prospective merging SMBH candidate owing to its merging features in Hubble Space Telescope imaging and double-peaked broa…

2020 The Astrophysical Journal
eHST 9
The Advanced Spectral Library (ASTRAL): Abundance Analysis of the Chemically Peculiar Star HR 465
DOI: 10.3847/1538-4357/aba361 Bibcode: 2020ApJ...899..166N

Carpenter, Kenneth G.; Nielsen, Krister E.; Wahlgren, Glenn M. +1 more

This paper presents the results of the spectrum analysis of the B-type magnetic chemically peculiar star HR 465. HR 465 shows unusual abundance patterns that vary with a period of 21.5 yr. Our observations are recorded at φ = 0.45, 0.68, and 0.85 of the spectroscopic period, where φ = 0 represents the phase of maximum flux in the photometric y-ban…

2020 The Astrophysical Journal
eHST 9
A Mechanistic Study on the Formation of Acetic Acid (CH3COOH) in Polar Interstellar Analog Ices Exploiting Photoionization Reflectron Time-of-flight Mass Spectrometry
DOI: 10.3847/1538-4357/abafa4 Bibcode: 2020ApJ...901...84K

Kleimeier, N. Fabian; Eckhardt, André K.; Kaiser, Ralf I.

Acetic acid (CH3COOH) is considered a key molecule in the formation of the simplest amino acid, glycine, and consequently peptides. It is ubiquitous in the interstellar medium and has been detected toward hot cores, in the coma of comets, and on the surface of the comet 67P/Churyumov-Gerasimenko by the Rosetta mission. Here we present t…

2020 The Astrophysical Journal
Rosetta 9
Multiepoch VLBI of L Dwarf Binary 2MASS J0746+2000AB: Precise Mass Measurements and Confirmation of Radio Emission from Both Components
DOI: 10.3847/1538-4357/ab9177 Bibcode: 2020ApJ...897...11Z

Hallinan, Gregg; Zhang, Qicheng; Golden, Aaron +2 more

Surveys have shown that up to 1/10th of all ultracool dwarfs (UCDs) are appreciable radio emitters, with their emission attributed to a combination of gyrosynchrotron radiation and the electron cyclotron maser instability. 2M J0746+2000AB is a close stellar binary comprised of an L0 and L1.5 dwarf that was previously identified as a source of 5 GH…

2020 The Astrophysical Journal
Gaia 9
Heliospheric Structure as Revealed by the 3-88 keV H ENA Spectra
DOI: 10.3847/1538-4357/ab5b14 Bibcode: 2020ApJ...888....1C

Schwadron, N. A.; Pogorelov, N. V.; Zank, G. P. +8 more

Energetic neutral atoms (ENAs) are an important tool for investigating the structure of the heliosphere. Recently, it was observed that fluxes of ENAs (with energy ≤55 keV) coming from the upwind and downwind regions of the heliosphere are similar in strength. This led the authors of these observations to hypothesize that the heliosphere is bubble…

2020 The Astrophysical Journal
SOHO 9
SUMER Measurement of the Fe X 3p43d 4D5/2,7/2 Energy Difference
DOI: 10.3847/1538-4357/abb2a6 Bibcode: 2020ApJ...902...21L

Landi, E.; Li, W.; Hutton, R. +1 more

Recent studies have shown that magnetic fields in the solar corona are strong enough to significantly mix the two 3p43d 4D5/2,7/2 levels in Cl-like Fe X. This mixing gives rise to a magnetically induced transition (MIT) component in the bright Fe X 257.3 Å line, commonly observed by current instrumentation, that ca…

2020 The Astrophysical Journal
SOHO 9
Uncovering the Primary X-Ray Emission and Possible Starburst Component in the Polarized NLS1 Mrk 1239
DOI: 10.3847/1538-4357/abb08a Bibcode: 2020ApJ...901..118B

Komossa, S.; Gallo, Luigi C.; Grupe, Dirk +2 more

X-ray observations of the unique NLS1 galaxy Mrk 1239 spanning 18 yr are presented. Data from XMM-Newton, Suzaku, Swift, and NuSTAR are combined to obtain a broadband, multi-epoch view of the source. There is spectral variability in the 3-10 keV band over the 18 yr. An analysis of the NuSTAR and Suzaku lightcurves also suggests rapid variability i…

2020 The Astrophysical Journal
Suzaku XMM-Newton 9