Search Publications
Striations in the Taurus molecular cloud: Kelvin-Helmholtz instability or MHD waves?
Falgarone, E.; Goldsmith, P. F.; Yıldız, U. A. +3 more
The origin of striations aligned along the local magnetic field direction in the translucent envelope of the Taurus molecular cloud is examined with new observations of 12CO and 13CO J = 2-1 emission obtained with the 10-m Submillimeter Telescope of the Arizona Radio Observatory. These data identify a periodic pattern of exce…
Anatomy of the AGN in NGC 5548. VI. Long-term variability of the warm absorber
Kaastra, J. S.; Kriss, G. A.; Bianchi, S. +13 more
Context. We observed the archetypal Seyfert 1 galaxy NGC 5548 in 2013-2014 in the context of an extensive multiwavelength campaign involving several satellites, which revealed the source to be in an extraordinary state of persistent heavy obscuration.
Aims: We re-analyzed the archival grating spectra obtained by XMM-Newton and Chandra between…
Ages of Massive Galaxies at 0.5 > z > 2.0 from 3D-HST Rest-frame Optical Spectroscopy
Franx, Marijn; Labbé, Ivo; van Dokkum, Pieter +10 more
We present low-resolution near-infrared stacked spectra from the 3D-HST survey up to z = 2.0 and fit them with commonly used stellar population synthesis models: BC03, FSPS10 (Flexible Stellar Population Synthesis), and FSPS-C3K. The accuracy of the grism redshifts allows the unambiguous detection of many emission and absorption features and thus …
Weakening of Jupiter's main auroral emission during January 2014
Fujimoto, M.; Yoshioka, K.; Steffl, A. J. +13 more
In January 2014 Jupiter's FUV main auroral oval decreased its emitted power by 70% and shifted equatorward by ∼1°. Intense, low-latitude features were also detected. The decrease in emitted power is attributed to a decrease in auroral current density rather than electron energy. This could be caused by a decrease in the source electron density, an…
Transition-region/Coronal Signatures and Magnetic Setting of Sunspot Penumbral Jets: Hinode (SOT/FG), Hi-C, and SDO/AIA Observations
Tiwari, Sanjiv K.; Winebarger, Amy R.; Moore, Ronald L. +1 more
Penumbral microjets (PJs) are transient narrow bright features in the chromosphere of sunspot penumbrae, first characterized by Katsukawa et al. using the Ca II H-line filter on Hinode's Solar Optical Telescope (SOT). It was proposed that the PJs form as a result of reconnection between two magnetic components of penumbrae (spines and interspines)…
An enhanced fraction of starbursting galaxies among high Eddington ratio AGNs
Daddi, E.; Ciesla, L.; Mullaney, J. R. +2 more
We investigate the star-forming properties of 1620 X-ray selected active galactic nuclei (AGN) host galaxies as a function of their specific X-ray luminosity (I.e. X-ray luminosity per unit host stellar mass) - a proxy of the Eddington ratio. Our motivation is to determine whether there is any evidence of a suppression of star formation at high Ed…
ASASSN-15lh: A Superluminous Ultraviolet Rebrightening Observed by Swift and Hubble
Baade, Dietrich; Wang, Lifan; Wheeler, J. Craig +9 more
We present and discuss ultraviolet and optical photometry from the Ultraviolet/Optical Telescope, X-ray limits from the X-Ray Telescope on Swift, and imaging polarimetry and ultraviolet/optical spectroscopy with the Hubble Space Telescope, all from observations of ASASSN-15lh. It has been classified as a hydrogen-poor superluminous supernova (SLSN…
Changes in the Physical Environment of the Inner Coma of 67P/Churyumov-Gerasimenko with Decreasing Heliocentric Distance
Jorda, L.; Lamy, P. L.; Lara, L. M. +43 more
The Wide Angle Camera of the OSIRIS instrument on board the Rosetta spacecraft is equipped with several narrow-band filters that are centered on the emission lines and bands of various fragment species. These are used to determine the evolution of the production and spatial distribution of the gas in the inner coma of comet 67P with time and helio…
Lightning climatology of exoplanets and brown dwarfs guided by Solar system data
Helling, Ch.; Hodosán, G.; Asensio-Torres, R. +2 more
Clouds form on extrasolar planets and brown dwarfs where lightning could occur. Lightning is a tracer of atmospheric convection, cloud formation and ionization processes as known from the Solar system, and may be significant for the formation of prebiotic molecules. We study lightning climatology for the different atmospheric environments of Earth…
Anatomy of outbursts and quiescent activity of Comet 29P/Schwassmann-Wachmann
Roche, Paul; Mottola, Stefano; Miles, Richard +4 more
Detailed morphological and photometric characterisation of Comet 29P in the optical region is presented comprising: (a) multi-filter observations of the outburst coma in 2010-2012 with the 2.0-m Faulkes Telescopes (FT); (b) high-cadence, high-precision photometry in May-September 2014; and (c) HST observations in March 1996 (WFPC2/F702W filter). O…