Search Publications
X-Ray and Radio Emission from Type IIn Supernova SN 2010jl
Chandra, Poonam; Fransson, Claes; Chevalier, Roger A. +2 more
We present all X-ray and radio observations of the Type IIn supernova SN 2010jl. The X-ray observations cover a period up to day 1500 with Chandra, XMM-Newton, NuSTAR, and Swift-X-ray Telescope (XRT). The Chandra observations after 2012 June, the XMM-Newton observation in 2013 November, and most of the Swift-XRT observations until 2014 December ar…
The Formation of IRIS Diagnostics. IV. The Mg II Triplet Lines as a New Diagnostic for Lower Chromospheric Heating
De Pontieu, Bart; Hansteen, Viggo; Carlsson, Mats +1 more
A triplet of subordinate lines of Mg ii exists in the region around the h&k lines. In solar spectra these lines are seen mostly in absorption, but in some cases can become emission lines. The aim of this work is to study the formation of this triplet, and investigate any diagnostic value they can bring. Using 3D radiative magnetohydrodynamic s…
CHAOS II. Gas-phase Abundances in NGC 5194
Skillman, Evan D.; Moustakas, John; Croxall, Kevin V. +2 more
We have observed NGC 5194 (M51a) as part of the CHemical Abundances of Spirals project. Using the Multi Object Double Spectrographs on the Large Binocular Telescope we are able to measure one or more of the temperature-sensitive auroral lines ([O iii] λ4363, [N ii] λ5755, [S iii] λ6312) and thus measure “direct” gas-phase abundances in 29 individu…
Diversity in extinction laws of Type Ia supernovae measured between 0.2 and 2 µm
Dahle, H.; Lundqvist, P.; Östlin, G. +36 more
We present ultraviolet (UV) observations of six nearby Type Ia supernovae (SNe Ia) obtained with the Hubble Space Telescope, three of which were also observed in the near-IR (NIR) with Wide-Field Camera 3. UV observations with the Swift satellite, as well as ground-based optical and NIR data provide complementary information. The combined data set…
Possible binary progenitors for the Type Ib supernova iPTF13bvn
Fraser, Morgan; Eldridge, J. J.; Smartt, Stephen J. +1 more
Cao et al. reported a possible progenitor detection for the Type Ib supernovae iPTF13bvn for the first time. We find that the progenitor is in fact brighter than the magnitudes previously reported by approximately 0.7-0.2 mag with a larger error in the bluer filters. We compare our new magnitudes to our large set of binary evolution models and fin…
Asteroseismic inference on rotation, gyrochronology and planetary system dynamics of 16 Cygni
García, R. A.; Chaplin, W. J.; Lund, M. N. +13 more
The solar analogues 16 Cyg A and B are excellent asteroseismic targets in the Kepler field of view and together with a red dwarf and a Jovian planet form an interesting system. For these more evolved Sun-like stars we cannot detect surface rotation with the current Kepler data but instead use the technique of asteroseimology to determine rotationa…
Molecular gas content in strongly lensed z ~ 1.5-3 star-forming galaxies with low infrared luminosities
Kneib, J. -P.; Schaerer, D.; Dessauges-Zavadsky, M. +10 more
To extend the molecular gas measurements to more typical star-forming galaxies (SFGs) with star formation rates SFR< 40 M⊙ yr-1 and stellar masses M∗< 2.5 × 1010M⊙ at z ~ 1.5-3, we have observed CO emission with the IRAM Plateau de Bure Interferometer and the IRAM 30 m telescope for five…
Classification and analysis of candidate impact crater-hosted closed-basin lakes on Mars
Mustard, John F.; Goudge, Timothy A.; Head, James W. +2 more
We present a new catalog of 205 candidate closed-basin lakes contained within impact craters across the surface of Mars. These basins have an inlet valley that incises the crater rim and flows into the basin but no visible outlet valley, and are considered candidate closed-basin lakes; the presence of a valley flowing into a basin does not necessi…
A Higher Efficiency of Converting Gas to Stars Pushes Galaxies at z ∼ 1.6 Well Above the Star-forming Main Sequence
Berta, S.; Lutz, D.; Daddi, E. +18 more
Local starbursts have a higher efficiency of converting gas into stars, as compared to typical star-forming galaxies at a given stellar mass, possibly indicative of different modes of star formation. With the peak epoch of galaxy formation occurring at z > 1, it remains to be established whether such an efficient mode of star formation is occur…
UV Surface Environment of Earth-like Planets Orbiting FGKM Stars through Geological Evolution
Kaltenegger, L.; Sasselov, D.; Rugheimer, S. +1 more
The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars in the circumstellar Habitable Zone for Earth …