Search Publications
A Variable Partial Covering Model for the Seyfert 1 Galaxy MCG -6-30-15
Ebisawa, Ken; Inoue, Hajime; Miyakawa, Takehiro
We propose a simple spectral model for the Seyfert 1 Galaxy MCG -6-30-15 that can explain most of the 1-40 keV spectral variation by a change of the partial covering fraction, similar to that proposed by Miller, Turner, and Reeves (2008, A&A, 483, 437). Our spectral model is composed of three continuum components: (1) a direct power-law compon…
A Population of Dust-rich Quasars at z ~ 1.5
Elvis, Martin; Willmer, Christopher N. A.; Magdis, Georgios E. +19 more
We report Herschel SPIRE (250, 350, and 500 µm) detections of 32 quasars with redshifts 0.5 <=z < 3.6 from the Herschel Multi-tiered Extragalactic Survey (HerMES). These sources are from a MIPS 24 µm flux-limited sample of 326 quasars in the Lockman Hole Field. The extensive multi-wavelength data available in the field permit con…
Star Formation History in Two Fields of the Small Magellanic Cloud Bar
Anderson, J.; Cignoni, M.; Tosi, M. +5 more
The Bar is the most productive region of the Small Magellanic Cloud in terms of star formation but also the least studied one. In this paper, we investigate the star formation history of two fields located in the SW and in the NE portion of the Bar using two independent and well-tested procedures applied to the color-magnitude diagrams of their st…
Direct imaging of extra-solar planets in star forming regions. Lessons learned from a false positive around IM Lupi
Absil, O.; Augereau, J. -C.; Surdej, J. +8 more
Context. Most exoplanet imagers consist of ground-based adaptive optics coronagraphic cameras which are currently limited in contrast, sensitivity and astrometric precision, but advantageously observe in the near-infrared window (1-5 µm). Because of these practical limitations, our current observational aim at detecting and characterizing pl…
Star Formation and AGN Activity in Galaxies Classified Using the 1.6 µm Bump and PAH Features at z = 0.4-2
Goto, Tomotsugu; Oyabu, Shinki; Ohyama, Youichi +17 more
We studied the star-formation and AGN activity of massive galaxies in the redshift range
Unveiling the nucleus of NGC 7172
Eckart, A.; Zuther, J.; Smajić, S. +1 more
Aims: We present the results of near-infrared (NIR) H + K European Southern Observatory SINFONI integral field spectroscopy (IFS) of the Seyfert 2 galaxy
(21) Lutetia spectrophotometry from Rosetta-OSIRIS images and comparison to ground-based observations
Jorda, L.; Lara, L. M.; Bertaux, J. -L. +40 more
Here we present some preliminary results on surface variegation found on (21) Lutetia from ROSETTA-OSIRIS images acquired on 2010-07-10. The spectrophotometry obtained by means of the two cameras NAC and WAC (Narrow and Wide Angle Cameras) is consistent with ground based observations, and does not show surface diversity above the data error bars. …
The Limit of Magnetic-shear Energy in Solar Active Regions
Moore, Ronald L.; Sterling, Alphonse C.; Falconer, David A.
It has been found previously, by measuring from active-region magnetograms a proxy of the free energy in the active region's magnetic field, (1) that there is a sharp upper limit to the free energy the field can hold that increases with the amount of magnetic field in the active region, the active region's magnetic flux content, and (2) that most …
Physical properties of craters on asteroid (21) Lutetia
Jorda, L.; Lara, L. M.; Bertaux, J. -L. +37 more
This paper presents an analysis of the physical properties of craters on asteroid (21) Lutetia, derived from images acquired by OSIRIS, the high-resolution cameras onboard ESA's spacecraft Rosetta. Crater morphology on (21) Lutetia fits very well with the general picture of what was known for previously visited small bodies, with a typical depth t…
The Remarkable High Pressure of the Local Leo Cold Cloud
Peek, J. E. G.; Heiles, Carl; Meyer, David M. +1 more
Using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope, we have obtained high-resolution ultraviolet spectra of the C I absorption toward two stars behind the Local Leo Cold Cloud (LLCC). At a distance (≈20 pc) that places it well inside the Local Bubble, the LLCC is the nearest example of the coldest known (T ≈ …