Search Publications
CO(1-0) line imaging of massive star-forming disc galaxies at z=1.5-2.2
Daddi, E.; Walter, F.; Riechers, D. A. +7 more
We present detections of the CO(J = 1-0) emission line in a sample of four massive star-forming galaxies at z ∼ 1.5-2.2 obtained with the Karl G. Jansky Very Large Array. Combining these observations with previous CO(2-1) and CO(3-2) detections of these galaxies, we study the excitation properties of the molecular gas in our sample sources. We fin…
Hot oxygen and carbon escape from the martian atmosphere
Lammer, H.; Shematovich, V. I.; Lichtenegger, H. +1 more
The escape of hot O and C atoms from the present martian atmosphere during low and high solar activity conditions has been studied with a Monte-Carlo model. The model includes the initial energy distribution of hot atoms, elastic, inelastic, and quenching collisions between the suprathermal atoms and the ambient cooler neutral atmosphere, and appl…
IC 348-SMM2E: a Class 0 proto-brown dwarf candidate forming as a scaled-down version of low-mass stars
Li, Di; Myers, Philip C.; Bouy, Hervé +7 more
We report on Submillimeter Array observations of the 870 µm continuum and CO (3-2), 13CO (2-1), and C18O (2-1) line emission of a faint object, SMM2E, near the driving source of the HH 797 outflow in the IC 348 cluster. The continuum emission shows an unresolved source for which we estimate a mass of gas and dust of 30 …
Detection of Supersonic Downflows and Associated Heating Events in the Transition Region above Sunspots
Golub, L.; Tian, H.; De Pontieu, B. +18 more
Interface Region Imaging Spectrograph data allow us to study the solar transition region (TR) with an unprecedented spatial resolution of 0.''33. On 2013 August 30, we observed bursts of high Doppler shifts suggesting strong supersonic downflows of up to 200 km s-1 and weaker, slightly slower upflows in the spectral lines Mg II h and k,…
Physical Interpretation of the Angle-dependent Magnetic Helicity Spectrum in the Solar Wind: The Nature of Turbulent Fluctuations near the Proton Gyroradius Scale
Klein, Kristopher G.; TenBarge, Jason M.; Howes, Gregory G. +1 more
Motivated by recent observations of distinct parallel and perpendicular signatures in magnetic helicity measurements segregated by wave period and angle between the local magnetic field and the solar wind velocity, this paper undertakes a comparison of three intervals of Ulysses data with synthetic time series generated from a physically motivated…
A three-dimensional extinction map of the Galactic anticentre from multiband photometry
Schultheis, M.; Huang, Y.; Chen, B. -Q. +8 more
We present a three-dimensional extinction map in the r band. The map has a spatial angular resolution, depending on latitude, between 3 and 9 arcmin and covers the entire Xuyi Schmidt Telescope Photometric Survey of the Galactic Anticentre (XSTPS-GAC) survey area of over 6000 deg2 for Galactic longitude 140 < l < 240 deg and latit…
Ground Level Enhancement in the 2014 January 6 Solar Energetic Particle Event
Gopalswamy, N.; Davila, J. M.; Yashiro, S. +4 more
We present a study of the 2014 January 6 solar energetic particle event which produced a small ground level enhancement (GLE), making it the second GLE of this unusual solar cycle 24. This event was primarily observed by the South Pole neutron monitors (increase of ~2.5%) while a few other neutron monitors recorded smaller increases. The associate…
Photometric magnetic-activity metrics tested with the Sun: application to Kepler M dwarfs
García, Rafael A.; Mathur, Savita; Salabert, David +1 more
The Kepler mission has been providing high-quality photometric data leading to many breakthroughs in the exoplanet search and in stellar physics. Stellar magnetic activity results from the interaction between rotation, convection, and magnetic field. Constraining these processes is important if we want to better understand stellar magnetic activit…
Fluctuations and Flares in the Ultraviolet Line Emission of Cool Stars: Implications for Exoplanet Transit Observations
Loyd, R. O. Parke; France, Kevin
Variations in stellar flux can potentially overwhelm the photometric signal of a transiting planet. Such variability has not previously been well-characterized in the ultraviolet lines used to probe the inflated atmospheres surrounding hot Jupiters. Therefore, we surveyed 38 F-M stars for intensity variations in four narrow spectroscopic bands: tw…
Possible Detection of the Stellar Donor or Remnant for the Type Iax Supernova 2008ha
Foley, Ryan J.; Rest, Armin; Fong, Wen-fai +5 more
Type Iax supernovae (SNe Iax) are thermonuclear explosions that are related to SNe Ia, but are physically distinct. The most important differences are that SNe Iax have significantly lower luminosity (1%-50% that of typical SNe Ia), lower ejecta mass (~0.1-0.5 M ⊙), and may leave a bound remnant. The most extreme SN Iax is SN 2008ha, wh…