Search Publications
Disks and Outflows in the Intermediate-mass Star-forming Region NGC 2071 IR
Li, Zhi-Yun; Sheehan, Patrick D.; Megeath, S. Thomas +13 more
We present Atacama Large Millimeter Array band 6/7 (1.3 mm/0.87 mm) and Very Large Array Ka-band (9 mm) observations toward NGC 2071 IR, an intermediate-mass star-forming region. We characterize the continuum and associated molecular line emission toward the most luminous protostars, i.e., IRS1 and IRS3, on ~100 au (0.″2) scales. IRS1 is partly re…
LoVoCCS. I. Survey Introduction, Data Processing Pipeline, and Early Science Results
Cooper, M. C.; Donahue, Megan; Miyatake, Hironao +19 more
We present the Local Volume Complete Cluster Survey (LoVoCCS; we pronounce it as "low-vox" or "law-vox," with stress on the second syllable), an NSF's National Optical-Infrared Astronomy Research Laboratory survey program that uses the Dark Energy Camera to map the dark matter distribution and galaxy population in 107 nearby (0.03 < z < 0.12…
The Twisted Magnetic Field of the Protobinary L483
Pattle, Kate; Coudé, Simon; Bourke, Tyler L. +16 more
We present H-band (1.65 µm) and SOFIA HAWC+ 154 µm polarization observations of the low-mass core L483. Our H-band observations reveal a magnetic field that is overwhelmingly in the E-W direction, which is approximately parallel to the bipolar outflow that is observed in scattered IR light and in single-dish 12CO observation…
Inconspicuous Solar Polar Coronal X-Ray Jets as the Source of Conspicuous Hinode/EUV Imaging Spectrometer Doppler Outflows
Harra, Louise K.; Panesar, Navdeep K.; Moore, Ronald L. +3 more
We examine in greater detail five events previously identified as being sources of strong transient coronal outflows in a solar polar region in Hinode/Extreme Ultraviolet (EUV) Imaging Spectrometer (EIS) Doppler data. Although relatively compact or faint and inconspicuous in Hinode/X-ray Telescope (XRT) soft-X-ray (SXR) images and in Solar Dynamic…
Exploring the Link between the X-Ray Power Spectra and Energy Spectra of Active Galactic Nuclei
Jin, Chichuan; Yuan, Weimin; Yang, Haonan
Active galactic nuclei (AGN) are generally considered the scaled-up counterparts of X-ray binaries (XRBs). It is known that the power spectral density (PSD) of the X-ray emission of XRBs shows significant evolution with spectral state. It is not clear whether AGN follow a similar evolutionary trend, however, though their X-ray emission and the PSD…
Revising Properties of Planet-Host Binary Systems. I. Methods and Pilot Study
Kraus, Adam L.; Mann, Andrew W.; Sullivan, Kendall
To fully leverage the statistical strength of the large number of planets found by projects such as the Kepler survey, the properties of planets and their host stars must be measured as accurately as possible. One key population for planet demographic studies is circumstellar planets in close binaries (ρ < 50 au), where the complex dynamical en…
What are the Composition and Power of the Jet in Cyg X-1?
Zdziarski, Andrzej A.; Egron, Elise
We calculate the electron-positron pair production rate at the base of the jet of Cyg X-1 by collisions of photons from its hot accretion flow using the measurement of its average soft gamma-ray spectra by the Compton Gamma Ray Observatory and INTEGRAL satellites. We have found that this rate approximately equals the flow rate of the leptons emitt…
SDSS-IV MaNGA: Cannibalism Caught in the Act-On the Frequency of Occurrence of Multiple Cores in Brightest Cluster Galaxies
Merrifield, Michael; Brownstein, Joel R.; Pan, Kaike +16 more
Although it is generally accepted that massive galaxies form in a two-phased fashion, beginning with a rapid mass buildup through intense starburst activities followed by primarily dry mergers that mainly deposit stellar mass at outskirts, the late time stellar mass growth of brightest cluster galaxies (BCGs), the most massive galaxies in the univ…
Mapping the X-Ray Corona Evolution of IRAS 13224-3809 with the Power Spectral Density
Chainakun, Poemwai; Luangtip, Wasuthep; Jiang, Jiachen +1 more
We develop the power spectral density (PSD) model to explain the nature of the X-ray variability in IRAS 13224-3809, including the full effects of the X-ray reverberation due to the lamppost source. We utilize 16 XMM-Newton observations individually as well as group them into three different luminosity bins: low, medium, and high. The soft (0.3-1 …
AGC 226178 and NGVS 3543: Two Deceptive Dwarfs toward Virgo
Cresci, Giovanni; Cannon, John M.; Haynes, Martha P. +21 more
The two sources AGC 226178 and NGVS 3543, an extremely faint, clumpy, blue stellar system and a low surface brightness dwarf spheroidal, are adjacent systems in the direction of the Virgo cluster. Both have been studied in detail previously, with it being suggested that they are unrelated normal dwarf galaxies or that NGVS 3543 recently lost its g…