Search Publications
Small Planets in the Galactic Context: Host Star Kinematics, Iron, and Alpha-element Enhancement
Bashi, Dolev; Zucker, Shay
We explored the occurrence rate of small close-in planets among Kepler target stars as a function of the iron abundance and the stellar total velocity {V}tot}. We estimated the occurrence rate of those planets by combining information from the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) and the California-Kepler S…
Origin of a Massive Hyper-runaway Subgiant Star LAMOST-HVS1: Implication from Gaia and Follow-up Spectroscopy
Mahler, Guillaume; Hattori, Kohei; Castro, Norberto +3 more
We report that LAMOST-HVS1 is a massive hyper-runaway subgiant star with a mass of 8.3 {M}⊙ and super-solar metallicity, which was ejected from the inner stellar disk of the Milky Way ∼33 {Myr} ago with the intrinsic ejection velocity of {568}-17+19 {km} {{{s}}}-1 (corrected for the streaming motion of …
Evolution of the Coronal Cavity From the Quiescent to Eruptive Phase Associated with Coronal Mass Ejection
West, Matthew J.; Srivastava, Nandita; Mierla, Marilena +2 more
We present the evolution of a coronal cavity encompassing its quiescent and eruptive phases in the lower corona. Using multiple vantage-point observations from the SDO/AIA, STEREO SECCHI/EUVI, and PROBA2/Sun Watcher with the APS and Image Processing (SWAP) extreme ultraviolet (EUV) imagers, we capture a sequence of quasi-static equilibria of the q…
Automated Swirl Detection Algorithm (ASDA) and Its Application to Simulation and Observational Data
Liu, Jiajia; Erdélyi, Robertus; Nelson, Chris J.
Swirling motions in the solar atmosphere have been widely observed in recent years and suggested to play a key role in channeling energy from the photosphere into the corona. Here, we present a newly developed Automated Swirl Detection Algorithm (ASDA) and discuss its applications. ASDA is found to be very proficient at detecting swirls in a varie…
On the emergence of THOUSANDS of absorption lines in the quasar PG 1411+442: a clumpy high-column density outflow from the broad emission-line region?
Tripp, Todd M.; Hamann, Fred; Veilleux, Sylvain +1 more
Quasar outflows are fundamental components of quasar environments that might play an important role in feedback to galaxy evolution. We report on the emergence of a remarkable new outflow absorption-line system in the quasar PG1411+442 (redshift ∼0.089) detected in the UV and visible with the Hubble Space Telescope Cosmic Origins Spectrograph and …
Constraints on positron annihilation kinematics in the inner Galaxy
Diehl, Roland; Siegert, Thomas; Panther, Fiona H. +4 more
Context. The annihilation of cosmic positrons with electrons in the interstellar medium results in the strongest persistent γ-ray line signal in the sky. For the past 50 yr, this 511 keV emission - predominantly from the galactic bulge region and from a low surface-brightness disk - has puzzled observers and theoreticians. A key issue for understa…
Molecular gas in radio galaxies in dense megaparsec-scale environments at z = 0.4-2.6
Castignani, G.; De Zotti, G.; Benoist, C. +4 more
Context. Low luminosity radio galaxies (LLRGs) typically reside in dense megaparsec-scale environments and are often associated with brightest cluster galaxies (BCGs). They are an excellent tool to study the evolution of molecular gas reservoirs in giant ellipticals, even close to the active galactic nucleus.
Aims: We investigate the role of …
Investigation of the origin of the anomalous microwave emission in Lambda Orionis
Doi, Yasuo; Onaka, Takashi; Kaneda, Hidehiro +5 more
The anomalous microwave emission (AME) still lacks a conclusive explanation. This excess of emission, roughly between 10 and 50 GHz, tends to defy attempts to explain it as synchrotron or free-free emission. The overlap with frequencies important for cosmic microwave background explorations, combined with a strong correlation with interstellar dus…
Spatial and seasonal variations in C3Hx hydrocarbon abundance in Titan's stratosphere from Cassini CIRS observations
Lombardo, Nicholas A.; Nixon, Conor A.; Achterberg, Richard K. +4 more
Of the C3Hx hydrocarbons, propane (C3H8) and propyne (methylacetylene, CH3C2H) were first detected in Titan's atmosphere during the Voyager 1 flyby in 1980. Propene (propylene, C3H6) was first detected in 2013 with data from the Composite InfraRed Spectrometer …
Outgassing-induced acceleration of comet 67P/Churyumov-Gerasimenko
Kramer, T.; Läuter, M.
Context. Cometary activity affects the orbital motion and rotation state through sublimation-induced forces. The availability of precise rotation-axis orientation and position data from the Rosetta mission allows us to accurately determine the outgassing of comet Churyumov-Gerasimenko/67P (67P).
Aims: We derived the observed non-gravitational…