Search Publications
A Double White-dwarf Cooling Sequence in ω Centauri
Salaris, M.; Anderson, J.; Bergeron, P. +4 more
We have applied our empirical-point-spread-function-based photometric techniques on a large number of calibration-related WFC3/UVIS UV-B exposures of the core of ω Cen, and found a well-defined split in the bright part of the white-dwarf cooling sequence (WDCS). The redder sequence is more populated by a factor of ~2. We can explain the separation…
Diagnosing the Time Dependence of Active Region Core Heating from the Emission Measure. II. Nanoflare Trains
Klimchuk, J. A.; Reep, J. W.; Bradshaw, S. J.
The time dependence of heating in solar active regions can be studied by analyzing the slope of the emission measure distribution coolward of the peak. In a previous study we showed that low-frequency heating can account for 0% to 77% of active region core emission measures. We now turn our attention to heating by a finite succession of impulsive …
SPT 0538-50: Physical Conditions in the Interstellar Medium of a Strongly Lensed Dusty Star-forming Galaxy at z = 2.8
Bock, J. J.; Ibar, E.; Murphy, E. J. +38 more
We present observations of SPT-S J053816-5030.8, a gravitationally lensed dusty star-forming galaxy (DSFG) at z = 2.7817 that was first discovered at millimeter wavelengths by the South Pole Telescope. SPT 0538-50 is typical of the brightest sources found by wide-field millimeter-wavelength surveys, being lensed by an intervening galaxy at moderat…
The 69 µm forsterite band in spectra of protoplanetary disks. Results from the Herschel DIGIT programme
Waters, L. B. F. M.; Dominik, C.; Henning, Th. +13 more
Context. We have analysed far-infrared spectra of 32 circumstellar disks around Herbig Ae/Be and T Tauri stars obtained within the Herschel key programme Dust, Ice and Gas in Time (DIGIT). The spectra were taken with the Photodetector Array Camera and Spectrometer (PACS) on board the Herschel Space Observatory. In this paper we focus on the detect…
Comparison of Ground-Based and Space-Based Longitudinal Magnetograms
Bertello, L.; Pevtsov, A. A.; Pietarila, A. +1 more
We compare photospheric line-of-sight magnetograms from the Synoptic Optical Long-term Investigations of the Sun (SOLIS) Vector Spectro-Magnetograph (VSM) instrument with observations from the 150-foot Solar Tower at Mt. Wilson Observatory (MWO), the Helioseismic and Magnetic Imager (HMI) on the Solar Dynamics Observatory (SDO), and the Michelson …
Very Large Array Mapping of the CO(1-0) Line in SMM J14011+0252
Baker, Andrew J.; Harris, Andrew I.; Sharon, Chelsea E. +1 more
We present high-resolution CO(1-0) observations of the lensed submillimeter galaxy (SMG) SMM J14011+0252 at z = 2.6. Comparison to the previously detected CO(3-2) line gives an intensity ratio of r 3, 1 = 0.97 ± 0.16 in temperature units, larger than is typical for SMGs but within the range seen in the low-z ultraluminous infrared galax…
Dynamics of the solar atmosphere above a pore with a light bridge
Heinzel, P.; Jurčák, J.; Berrilli, F. +3 more
Context. Solar pores are small sunspots lacking a penumbra that have a prevailing vertical magnetic-field component. They can include light bridges at places with locally reduced magnetic field. Like sunspots, they exhibit a wide range of oscillatory phenomena.
Aims: A large isolated pore with a light bridge (NOAA 11005) is studied to obtain …
Homologous Flux Ropes Observed by the Solar Dynamics Observatory Atmospheric Imaging Assembly
Li, Ting; Zhang, Jun
We present the first Solar Dynamics Observatory observations of four homologous flux ropes in the active region (AR) 11745 on 2013 May 20-22. The four flux ropes are all above the neutral line of the AR, with endpoints anchoring at the same region, and have a generally similar morphology. The first three flux ropes rose with a velocity of less tha…
Simulations of the merging galaxy cluster Abell 3376
Lima Neto, Gastão B.; Machado, Rubens E. G.
Observed galaxy clusters often exhibit X-ray morphologies suggestive of recent interaction with an infalling subcluster. A3376 is a nearby (z = 0.046) massive galaxy cluster whose bullet-shaped X-ray emission indicates that it may have undergone a recent collision. It displays a pair of Mpc-scale radio relics and its brightest cluster galaxy is lo…
An examination of the spectral variability in NGC 1365 with Suzaku
Elvis, M.; Nardini, E.; Brenneman, L. W. +1 more
We present jointly analysed data from three deep Suzaku observations of NGC 1365. These high-signal-to-noise spectra enable us to examine the nature of this variable, obscured active galactic nucleus (AGN) in unprecedented detail on time-scales ranging from hours to years. We find that in addition to the power-law continuum and absorption from ion…