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Mapping Compound Cosmic Telescopes Containing Multiple Projected Cluster-scale Halos
Zabludoff, Ann I.; Keeton, Charles R.; Wong, Kenneth C. +1 more
Lines of sight with multiple projected cluster-scale gravitational lenses have high total masses and complex lens plane interactions that can boost the area of magnification, or étendue, making detection of faint background sources more likely than elsewhere. To identify these new "compound" cosmic telescopes, we have found directions in the sky w…
Applying an Automatic Image-Processing Method to Synoptic Observations
Tlatov, Andrey G.; Vasil'eva, Valeria V.; Makarova, Valentina V. +1 more
We used an automatic image-processing method to detect solar-activity features observed in white light at the Kislovodsk Solar Station. This technique was applied to automatically or semi-automatically detect sunspots and active regions. The results of this automated recognition were verified with statistical data available from other observatorie…
Photometric Redshifts in the Hawaii-Hubble Deep Field-North (H-HDF-N)
Lehmer, B. D.; Alexander, D. M.; Bauer, F. E. +11 more
We derive photometric redshifts (z phot) for sources in the entire (~0.4 deg2) Hawaii-Hubble Deep Field-North (H-HDF-N) field with the EAzY code, based on point-spread-function-matched photometry of 15 broad bands from the ultraviolet (U band) to mid-infrared (IRAC 4.5 µm). Our catalog consists of a total of 131,678 sou…
Prospects for Measuring Supermassive Black Hole Masses with Future Extremely Large Telescopes
Barth, Aaron J.; Do, Tuan; Larkin, James E. +6 more
The next generation of giant-segmented mirror telescopes (>20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole ma…
Cassini/VIMS Observes Rough Surfaces on Titan's Punga Mare in Specular Reflection
Sotin, Christophe; Barnes, Jason W.; Soderblom, Jason M. +7 more
PAH formation in O-rich planetary nebulae
Zijlstra, A. A.; Jones, D.; Lagadec, E. +2 more
Polycyclic aromatic hydrocarbons (PAHs) have been observed in O-rich planetary nebulae towards the Galactic bulge. This combination of oxygen-rich and carbon-rich material, known as dual-dust or mixed chemistry, is not expected to be seen around such objects. We recently proposed that PAHs could be formed from the photodissociation of CO in dense …
A mid-infrared view of the inner parsecs of the Seyfert galaxy Mrk 1066 using CanariCam/GTC
Esquej, P.; Aretxaga, I.; Díaz-Santos, T. +10 more
We present mid-infrared (MIR) imaging and spectroscopic data of the Seyfert 2 galaxy Mrk 1066 obtained with CanariCam (CC) on the 10.4-m Gran Telescopio CANARIAS (GTC). The galaxy was observed in imaging mode with an angular resolution of 0.24 arcsec (54 pc) in the Si-2 filter (8.7 µm). The image reveals a series of star-forming knots within…
Cluster Candidates around Low-power Radio Galaxies at z ~ 1-2 in COSMOS
Castignani, G.; De Zotti, G.; Chiaberge, M. +2 more
We search for high-redshift (z ~1-2) galaxy clusters using low power radio galaxies (FR I) as beacons and our newly developed Poisson probability method based on photometric redshift information and galaxy number counts. We use a sample of 32 FR Is within the Cosmic Evolution Survey (COSMOS) field from the Chiaberge et al. catalog. We derive a rel…
Probing the mass and anisotropy of the Milky Way gaseous halo: sight-lines toward Mrk 421 and PKS 2155-304
Krongold, Y.; Mathur, S.; Gupta, A. +1 more
We recently found that the halo of the Milky Way contains a large reservoir of warm-hot gas that accounts for large fraction of the missing baryons from the Galaxy. The average physical properties of this circumgalactic medium (CGM) are determined by combining average absorption and emission measurements along several extragalactic sightlines. How…
Spectroscopy of BL Lacertae objects of extraordinary luminosity
Sbarufatti, B.; Falomo, R.; Treves, A. +1 more
Aims: We aim to determine the redshift (or stringent lower limits) of a number of bright BL Lacs objects.
Methods: We secured optical and near-infrared medium-resolution spectra of four bright BL Lac objects of unknown redshift using the spectrograph X-Shooter at the ESO-VLT.
Results: In spite of the high quality of the spectra and …