Search Publications
Prediction of Supernova Rates in Known Galaxy-Galaxy Strong-lens Systems
Kang, Xi; Mao, Shude; Bolton, Adam S. +3 more
We propose a new strategy of finding strongly lensed supernovae (SNe) by monitoring known galaxy-scale strong-lens systems. Strongly lensed SNe are potentially powerful tools for the study of cosmology, galaxy evolution, and stellar populations, but they are extremely rare. By targeting known strongly lensed star-forming galaxies, our strategy sig…
Physical Properties of II Zw 40's Super Star Cluster and Nebula: New Insights and Puzzles from UV Spectroscopy
Leitherer, Claus; Lee, Janice C.; Levesque, Emily M. +1 more
We analyze far-ultraviolet spectra and ancillary data of the super star cluster SSC-N and its surrounding H II region in the nearby dwarf galaxy II Zw 40. From the ultraviolet spectrum, we derive a low internal reddening of E(B - V) = 0.07 ± 0.03, a mass of (9.1 ± 1.0) × 105 M ⊙, a bolometric luminosity of (1.1 ± 0.1) × 10
Chemically Dissected Rotation Curves of the Galactic Bulge from Main-sequence Proper Motions
Brown, Thomas M.; Gennaro, Mario; Clarkson, William I. +9 more
We report results from an exploratory study implementing a new probe of Galactic evolution using archival Hubble Space Telescope imaging observations. Precise proper motions are combined with photometric relative metallicity and temperature indices, to produce the proper-motion rotation curves of the Galactic bulge separately for metal-poor and me…
Electron Acceleration and Jet-facilitated Escape in an M-class Solar Flare on 2002 August 19
Fleishman, Gregory D.; Glesener, Lindsay
Sudden jets of collimated plasma arise from many locations on the Sun, including active regions. The magnetic field along which a jet emerges is often open to interplanetary space, offering a clear “escape route” for any flare-accelerated electrons, making jets lucrative targets for studying particle acceleration and the solar sources of transient…
The Formation and Evolution of Galactic Disks with APOGEE and the Gaia Survey
Zhao, Gang; Li, Chengdong; Zhai, Meng +1 more
We explore the structure and evolutionary history of Galactic disks with Apache Point Observatory Galactic Evolution Experiment data release 13 (DR13 hereafter) and Gaia Tycho-Gaia Astrometric Solution data. We use the [α/M] ratio to allocate stars into particular Galactic components to elucidate the chemical and dynamical properties of the thin a…
A Cool Core Disturbed: Observational Evidence for the Coexistence of Subsonic Sloshing Gas and Stripped Shock-heated Gas around the Core of RX J1347.5-1145
Kohno, Kotaro; Oguri, Masamune; Iono, Daisuke +13 more
RX J1347.5-1145 (z = 0.451) is one of the most luminous X-ray galaxy clusters; it hosts a prominent cool core and exhibits a signature of a major merger. We present the first direct observational evidence for the subsonic nature of the sloshing motion of the cool core. We find that a residual X-ray image from the Chandra X-ray Observatory after re…
Propagating Spectropolarimetric Disturbances in a Large Sunspot
Erdélyi, R.; Ermolli, I.; Murabito, M. +7 more
We present results derived from the analysis of spectropolarimetric measurements of active region AR12546, which represents one of the largest sunspots to have emerged onto the solar surface over the last 20 years. The region was observed with full-Stokes scans of the Fe I 617.3 nm and Ca II 854.2 nm lines with the Interferometric BIdimensional Sp…
Stellar and Planetary Characterization of the Ross 128 Exoplanetary System from APOGEE Spectra
Cunha, Katia; Smith, Verne V.; Souto, Diogo +14 more
The first detailed chemical abundance analysis of the M-dwarf (M4.0) exoplanet-hosting star Ross 128 is presented here, based upon near-infrared (1.5-1.7 µm), high-resolution (R ∼ 22,500) spectra from the SDSS Apache Point Galactic Evolution Experiment survey. We determined precise atmospheric parameters T eff = 3231 ± 100 K, log …
Discovery of an Ultraviolet Counterpart to an Ultrafast X-Ray Outflow in the Quasar PG 1211+143
Kriss, Gerard A.; Lee, Julia C.; Danehkar, Ashkbiz +5 more
We observed the quasar PG 1211+143 using the Cosmic Origins Spectrograph on the Hubble Space Telescope in 2015 April as part of a joint campaign with the Chandra X-ray Observatory and the Jansky Very Large Array. Our ultraviolet spectra cover the wavelength range 912-2100 Å. We find a broad absorption feature (∼ 1080 {km} {{{s}}}-1) at …
Spectral and Imaging Observations of a Current Sheet Region in a Small-scale Magnetic Reconnection Event
Xue, Zhike; Yan, Xiaoli; Wang, Jincheng +5 more
We report a possible current sheet region associated with a small-scale magnetic reconnection event by using the spectral and imaging observations of the Interface Region Imaging Spectrograph (IRIS) and the magnetograms obtained by the Solar Dynamics Observatory on 2016 August 08. The length and width of the current sheet region are estimated to b…