Search Publications
Spitzer Space Telescope observations of bilobate comet 8P/Tuttle
Jorda, L.; Lamy, P. L.; Groussin, O. +4 more
Context. Comet 8P/Tuttle is a nearly isotropic comet whose physical properties are poorly known and might be different from those of ecliptic comets owing to their different origin. Two independent observations have shown that 8P/Tuttle has a bilobate nucleus.
Aims: Our goal is to determine the physical properties of the nucleus (size, shape,…
Maps of Tethys' thermophysical properties
Spencer, J. R.; Howett, C. J. A.; Segura, M. +2 more
On 11th April 2015 Cassini's Composite Infrared Spectrometer (CIRS) made a series of observations of Tethys' daytime anti-Saturn hemisphere over a nine-hour time period. During this time the sub-spacecraft position was remarkably stable (0.3° S to 3.9° S; 153.2° W to 221.8° W), and so these observations provide unprecedented coverage of diurnal te…
The Broadband X-Ray Spectrum of the X-Ray-obscured Type 1 AGN 2MASX J193013.80+341049.5
Walton, Dominic J.; Stern, Daniel; Assef, Roberto J. +6 more
We present results from modeling the broadband X-ray spectrum of the Type 1 active galactic nucleus (AGN) 2MASX J193013.80+341049.5 using NuSTAR, Swift, and archival XMM-Newton observations. We find this source to be highly X-ray obscured, with column densities exceeding 1023 cm-2 across all epochs of X-ray observations, span…
Searching for Wide Companions and Identifying Circum(sub)stellar Disks through PSF Fitting of Spitzer/IRAC Archival Images
Kraus, Adam L.; Martinez, Raquel A.
Direct imaging surveys have discovered wide-orbit planetary-mass companions that challenge existing models of both star and planet formation, but their demographics remain poorly sampled. We have developed an automated binary companion point-spread function (PSF) fitting pipeline to take advantage of Spitzer's infrared sensitivity to planetary-mas…
Third-nearest WZ Sge-Type dwarf nova candidate ASASSN-14dx classified on the basis of Gaia Data Release 2
Nogami, Daisaku; Monard, Berto; Ohshima, Tomohito +8 more
ASASSN-14dx showed an extraordinary outburst whose features are a small outburst amplitude (∼2.3 mag) and long duration (>4 yr). Because we found a long observational gap of 123 d before the outburst detection, we propose that the main outburst plateau was missed and that this outburst is just a "fading tail" often seen after the WZ Sge-type su…
UV slope of z ∼ 3 bright (L > L*) Lyman-break galaxies in the COSMOS field
Castellano, M.; Pentericci, L.; Santini, P. +7 more
Context. The analysis of the UV slope β of Lyman-break galaxies (LBG) at different luminosities and redshifts is fundamental for understanding their physical properties, and in particular, their dust extinction.
Aims: We analyse a unique sample of 517 bright (L > L*) LBGs at redshift z ∼ 3 in order to characterise the distributi…
Tiny grains shining bright in the gaps of Herbig Ae transitional discs
Monnier, John D.; Kraus, Stefan; Federrath, Christoph +7 more
This work presents a study of two Herbig Ae transitional discs, Oph IRS 48 and HD 169142; which both have reported rings in their dust density distributions. We use Keck-II/NIRC2 adaptive optics imaging observations in the L' filter (3.8 µm) to probe the regions of these discs inwards of {∼ }20 au from the star. We introduce our method for i…
Galaxy rotation curve from classical Cepheids
Gnaciński, Piotr
The galaxy rotation curve is usually assumed to be flat. However, some galaxies have rotation curves that are lower than the flat rotation curve. In our galaxy, the Keplerian rotation of interstellar clouds in the galactic longitude l = 135° was observed. We use a kinematic approach to derive the rotational velocity of classical Cepheids. The rota…
Revised wavelength and spectral response calibrations for AKARI near-infrared grism spectroscopy: Post-cryogenic phase
Nakagawa, Takao; Baba, Shunsuke; Onaka, Takashi +2 more
We present a new calibration for the second-order light contamination in the near-infrared grism spectroscopy with the Infrared Camera aboard AKARI, specifically for the post-cryogenic phase of the satellite (Phase 3). Following our previous work on the cryogenic phase (Phases 1 and 2), the wavelength and spectral response calibrations were revise…
Active galactic nucleus selection in the AKARI NEP-Deep field with the fuzzy support vector machine algorithm
Goto, Tomotsugu; Matsuhara, Hideo; Poliszczuk, Artem +15 more
The aim of this work is to create a new catalog of reliable active galactic nucleus (AGN) candidates selected from the AKARI NEP-Deep field. Selection of the AGN candidates was done by applying a fuzzy support vector machine algorithm, which allows the incorporation of measurement uncertainties into the classification process. The training dataset…