Search Publications
SOFIA/FORCAST Galactic Center Legacy Survey: Overview
Morris, Mark R.; Longmore, Steven N.; García-Marín, Macarena +12 more
The Galactic Center contains some of the most extreme conditions for star formation in our Galaxy, as well as many other phenomena that are unique to this region. Given our relative proximity to the Galactic Center, we are able to study details of physical processes to a level that is simply not yet possible for more distant galaxies, yielding an …
Chemistry and Physics of a Low-metallicity Hot Core in the Large Magellanic Cloud
Onaka, Takashi; Aikawa, Yuri; Shimonishi, Takashi +5 more
We here present the results of 0.1 pc scale observations in 250 and 350 GHz toward a newly-discovered hot molecular core in a nearby low-metallicity galaxy, the Large Magellanic Cloud (LMC), with the Atacama Large Millimeter/submillimeter Array. A variety of C/N/O/Si/S-bearing molecules are detected toward the high-mass young stellar object, ST16.…
Possible Production of Solar Spicules by Microfilament Eruptions
Yurchyshyn, Vasyl; Moore, Ronald L.; Sterling, Alphonse C. +1 more
We examine Big Bear Solar Observatory (BBSO) Goode Solar Telescope (GST) high spatial resolution (0"06), high-cadence (3.45 s), Hα-0.8 Å images of central-disk solar spicules, using data of Samanta et al. We compare with coronal-jet chromospheric-component observations of Sterling et al. Morphologically, bursts of spicules, referred to as "enhance…
A Comparison of UV and Optical Metallicities in Star-forming Galaxies
Kewley, Lisa J.; Acharyya, Ayan; Rigby, Jane R. +4 more
Our ability to study the properties of the interstellar medium in the earliest galaxies will rely on emission-line diagnostics at rest-frame ultraviolet (UV) wavelengths. In this work, we identify metallicity-sensitive diagnostics using UV emission lines. We compare UV-derived metallicities with standard, well-established optical metallicities usi…
MCSED: A Flexible Spectral Energy Distribution Fitting Code and Its Application to z ∼ 2 Emission-line Galaxies
Schneider, Donald P.; Gronwall, Caryl; Ciardullo, Robin +7 more
We present MCSED, a new spectral energy distribution (SED) fitting code that mates flexible stellar evolution calculations with the Markov Chain Monte Carlo algorithms of the software package emcee. It takes broad-, intermediate-, and narrowband photometry, emission-line fluxes, and/or absorption-line spectral indices and returns probability distr…
Detailed Iron-peak Element Abundances in Three Very Metal-poor Stars
Roederer, Ian U.; Sneden, Christopher; Cowan, John J. +4 more
We have obtained new detailed abundances of the Fe-group elements Sc through Zn (Z = 21-30) in three very metal-poor ([Fe/H] ≈ -3) stars: BD+03o740, BD-13o3442, and CD-33o1173. High-resolution ultraviolet Hubble Space Telescope/Space Telescope Imaging Spectrograph spectra in the wavelength range 2300-3050 Å were ga…
Long-term Orbital Evolution of Galactic Satellites and the Effects on Their Star Formation Histories
Chiba, Masashi; Miyoshi, Takahiro
We investigate the orbital motions of dwarf spheroidal galaxies (dSphs) in the halo of the Milky Way (MW) to understand their possible effects on the diversity of the star formation histories seen in these MW satellites. In this work, we explicitly consider a time-varying gravitational potential due to the growth of the MW's dark halo mass to calc…
Optical Observations Reveal Strong Evidence for High-energy Neutrino Progenitor
Rebolo, R.; Buckley, D. A. H.; Böttcher, M. +32 more
We present the earliest astronomical observation of a high-energy neutrino error box of which the variability was discovered after high-energy-neutrino detection. The one robotic telescope of the MASTER global international networks automatically imaged the error box of the very high-energy-neutrino event IceCube-170922A. Observations were carried…
Discovery of a Young Stellar Snake with Two Dissolving Cores in the Solar Neighborhood
Tian, Hai-Jun
We report the discovery of a young (only 30-40 Myr) snake-like structure (dubbed a stellar snake) in the solar neighborhood from Gaia DR2. The average distance of this structure is about 310 pc from us. Both the length and width are over 200 pc, but the thickness is only about 80 pc. The snake has one tail and two dissolving cores, which can be cl…
IRIS Si IV Line Profiles at Flare Ribbons as Indications of Chromospheric Condensation
Ding, M. D.; Li, Y.; Li, D. +3 more
We present temporal variations of the Si IV line profiles at the flare ribbons in three solar flares observed by the Interface Region Imaging Spectrograph. In the M1.1 flare on 2014 September 6 and the X1.6 flare on 2014 September 10, the Si IV line profiles evolve from wholly redshifted to red-wing enhanced with the flare development. However, in…