Search Publications
Vertical settling and radial segregation of large dust grains in the circumstellar disk of the Butterfly Star
Stapelfeldt, K. R.; Wolf, S.; Pontoppidan, K. M. +4 more
Context. Circumstellar disks are considered to be the environment for the formation of planets. The growth of dust grains in these disks is the first step in the core accretion-gas capture planet formation scenario. Indicators and evidence of disk evolution can be traced in spatially resolved images and the spectral energy distribution (SED) of th…
Deuterated Molecules in Orion KL from Herschel/HIFI
Bergin, Edwin A.; Neill, Justin L.; Crockett, Nathan R. +2 more
We present a comprehensive study of the deuterated molecules detected in the fullband HIFI survey of the Orion Kleinmann-Low nebula (Orion KL) region. Ammonia, formaldehyde, and methanol and their singly deuterated isotopologues are each detected through numerous transitions in this survey with a wide range in optical depths and excitation conditi…
Can laboratory tholins mimic the chemistry producing Titan's aerosols? A review in light of ACP experimental results
Poch, O.; Szopa, C.; Coll, P. +7 more
The first results obtained by the ACP experiment onboard Huygens probe revealed that the main products obtained after thermolysis of Titan's collected aerosols, were ammonia (NH3) and hydrogen cyanide (HCN). Titan's aerosols, and their laboratory analogues named tholins, have been the subject of experimental or theoretical studies durin…
The Far-infrared, UV, and Molecular Gas Relation in Galaxies up to z = 2.5
Berta, S.; Magnelli, B.; Nordon, R. +10 more
We use the infrared excess (IRX) FIR/UV luminosity ratio to study the relation between the effective UV attenuation (A IRX) and the UV spectral slope (β) in a sample of 450 1 < z < 2.5 galaxies. The FIR data are from very deep Herschel observations in the GOODS fields that allow us to detect galaxies with star formation rates (SFR…
Parallaxes and Proper Motions of Ultracool Brown Dwarfs of Spectral Types Y and Late T
Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R. +5 more
We present astrometric measurements of 11 nearby ultracool brown dwarfs of spectral types Y and late-T, based on imaging observations from a variety of space-based and ground-based telescopes. These measurements have been used to estimate relative parallaxes and proper motions via maximum likelihood fitting of geometric model curves. To compensate…
Reconstruction of broad features in the primordial spectrum and inflaton potential from Planck
Hazra, Dhiraj Kumar; Smoot, George F.; Shafieloo, Arman
With the recently published Cosmic Microwave Background data from Planck we address the optimized binning of the primordial power spectrum. As an important modification to the usual binning of the primordial spectrum, along with the spectral amplitude of the bins, we allow the position of the bins also to vary. This technique enables us to address…
Full-sky CMB lensing reconstruction in presence of sky-cuts
Benabed, K.; Benoit-Lévy, A.; Cardoso, J. -F. +3 more
We consider the reconstruction of the CMB lensing potential and its power spectrum on the full sphere in presence of sky-cuts due to point sources and Galactic contamination. These two effects are treated separately. Small regions contaminated by point sources are filled in using constrained Gaussian realizations. The Galactic plane is simply remo…
The Nature of Stable Soft X-Ray Emissions in Several Types of Active Galactic Nuclei Observed by Suzaku
Makishima, Kazuo; Nakazawa, Kazuhiro; Yamada, Shin'ya +3 more
To constrain the origin of the soft X-ray excess phenomenon seen in many active galactic nuclei, the intensity-correlated spectral analysis, developed by Noda et al. (2011, PASJ, 63, S925) for Markarian 509, was applied to wide-band (0.5-45 keV) Suzaku data of five representative objects with a relatively weak reflection signature. They are the ty…
Photometric Constraints on the Redshift of z ~ 10 Candidate UDFj-39546284 from Deeper WFC3/IR+ACS+IRAC Observations over the HUDF
Brammer, G.; Trenti, M.; Oesch, P. A. +10 more
Ultra-deep WFC3/IR observations on the HUDF from the HUDF09 program revealed just one plausible z ~ 10 candidate, UDFj-39546284. UDFj-39546284 had all the properties expected of a galaxy at z ~ 10 showing (1) no detection in the deep ACS+WFC3 imaging data blueward of the F160W band, exhibiting (2) a blue spectral slope redward of the break, and sh…
Radio-loud Active Galactic Nucleus: Is There a Link between Luminosity and Cluster Environment?
Hardcastle, M. J.; Croston, J. H.; Kraft, R. P. +3 more
We present here the first results from the Chandra ERA (Environments of Radio-loud AGN) Large Project, characterizing the cluster environments of a sample of 26 radio-loud active galactic nuclei (AGNs) at z ~ 0.5 that covers three decades of radio luminosity. This is the first systematic X-ray environmental study at a single epoch, and has allowed…