Search Publications
Nebular and global properties of the gravitationally lensed galaxy "the 8 o'clock arc"
Schaerer, D.; Dessauges-Zavadsky, M.; Richard, J. +2 more
We present the analysis of new near-infrared, intermediate-resolution spectra of the gravitationally lensed galaxy "the 8 o'clock arc" at zsys = 2.7350 obtained with the X-shooter spectrograph on the Very Large Telescope. These rest-frame optical data, combined with Hubble and Spitzer Space Telescopes images, provide very valuable infor…
Modeling the atmospheric limb emission of CO 2 at 4.3 µm in the terrestrial planets
López-Puertas, M.; López-Valverde, M. A.; Gilli, G. +5 more
The MIPAS instrument on board Envisat, in Earth orbit, the PFS and OMEGA instruments on Mars Express, and VIRTIS on board Venus Express are currently providing a dataset of limb measurements of the CO 2 atmospheric fluorescence emission at 4.3-µm from the upper atmosphere of the three planets. These measurements represent an excel…
Detection of a large massive circumstellar disk around a high-mass young stellar object in the Carina Nebula
Preibisch, T.; Zinnecker, H.; McCaughrean, M. J. +5 more
Context. The characterization of circumstellar disks around young stellar objects can provide important information about the process of star formation and the possible formation of planetary systems.
Aims: We investigate the spatial structure and the spectral energy distribution of a newly discovered edge-on circumstellar disk around an opti…
The evolution of electron current sheet and formation of secondary islands in guide field reconnection
Yang, Z.; Wang, S.; Huang, C. +3 more
Two-dimensional (2-D) particle-in-cell (PIC) simulations are performed to investigate the evolution of the electron current sheet (ECS) in guide field reconnection. The ECS is formed by electrons accelerated by the inductive electric field in the vicinity of the X line, which is then extended along the x direction due to the imbalance between the …
The Efficacy of Galaxy Shape Parameters in Photometric Redshift Estimation: A Neural Network Approach
Lotz, J.; Griffith, R. L.; Singal, J. +2 more
We present a determination of the effects of including galaxy morphological parameters in photometric redshift estimation with an artificial neural network method. Neural networks, which recognize patterns in the information content of data in an unbiased way, can be a useful estimator of the additional information contained in extra parameters, s…
Suzaku Observes Weak Flares from IGR J17391-3021 Representing a Common Low-activity State in this Supergiant Fast X-ray Transient
Chaty, S.; Tomsick, J. A.; Rodriguez, J. +4 more
We present an analysis of a 37 ks observation of the supergiant fast X-ray transient IGR J17391-3021 (= XTE J1739-302) gathered with Suzaku. The source evolved from quiescence to a low-activity level culminating in three weak flares lasting ~3 ks each in which the peak luminosity is only a factor of five times that of the pre-flare luminosity. The…
Hydrogen ENA-cloud observation and modeling as a tool to study star-exoplanet interaction
Holmström, M.; Lammer, H.; Khodachenko, M. L. +2 more
During the previous years spacecraft observations of so-called Energetic Neutral Atoms (ENAs) have become an important remote-sensing technique in planetary science for analyzing the solar wind plasma flow around the upper atmospheric environments of Solar System bodies. ENAs are produced whenever solar- or stellar wind protons interact via charge…
X-ray observations of sub-mm LABOCA galaxies in the eCDFS
Comastri, A.; Georgantopoulos, I.; Rovilos, E.
We explore the X-ray properties of the 126 sub-mm galaxies (SMGs) of the LABOCA survey in the CDFS and the eCDFS regions. SMGs are believed to experience massive episodes of star formation. Our goal is to examine whether star formation coexists with AGN activity, determine the fraction of highly obscured AGN, and finally to obtain an idea of the d…
Comparing Spatial Distributions of Solar Prominence Mass Derived from Coronal Absorption
Alexander, David; Kilper, Gary; Gilbert, Holly +1 more
In a previous study, Gilbert et al. derived the column density and total mass of solar prominences using a new technique, which measures how much coronal radiation in the Fe XII (195 Å) spectral band is absorbed by prominence material, while considering the effects of both foreground and background radiation. In the present work, we apply this met…
Interstellar Silicate Dust in Five Quasar Absorption Systems
York, Donald G.; Kulkarni, Varsha P.; Welty, Daniel E. +3 more
We report on a study of interstellar silicate dust in five quasar absorption systems at 0.44 < z abs < 1.31 toward quasars Q0235+164, 3C196, Q0852+3435, Q0937+5628, and Q1203+0634, using data from the Infrared Spectrograph on board the Spitzer Space Telescope. In the absorbers toward Q0235+164, 3C196, Q0852+3435, and Q0937+5628, t…