Search Publications
Probing features in inflaton potential and reionization history with future CMB space observations
Ballardini, Mario; Finelli, Fabio; Paoletti, Daniela +4 more
We consider the prospects of probing features in the primordial power spectrum with future Cosmic Microwave Background (CMB) polarization measurements. In the scope of the inflationary scenario, such features in the spectrum can be produced by local non-smooth pieces in an inflaton potential (smooth and quasi-flat in general) which in turn may ori…
The Gas Composition and Deep Cloud Structure of Jupiter's Great Red Spot
Wong, M. H.; Orton, G. S.; de Pater, I. +3 more
We have obtained high-resolution spectra of Jupiter’s Great Red Spot (GRS) between 4.6-5.4 µm using telescopes on Mauna Kea to derive gas abundances and to constrain its cloud structure between 0.5-5 bars. We used line profiles of deuterated methane (CH3D) at 4.66 µm to infer the presence of an opaque cloud at 5 ± 1 bars. Fr…
Beaming electromagnetic (or heat-flux) instabilities from the interplay with the electron temperature anisotropies
Lazar, M.; Poedts, S.; Yoon, P. H. +1 more
In space plasmas, kinetic instabilities are driven by the beaming (drifting) components and/or the temperature anisotropy of charged particles. The heat-flux instabilities are known in the literature as electromagnetic modes destabilized by the electron beams (or strahls) aligned to the interplanetary magnetic field. A new kinetic approach is prop…
Hubble Space Telescope Wide Field Camera 3 Observations of Escaping Lyman Continuum Radiation from Galaxies and Weak AGN at Redshifts z ∼ 2.3-4.1
Koekemoer, Anton M.; Inoue, Akio K.; Jiang, Linhua +9 more
We present observations of escaping Lyman Continuum (LyC) radiation from 34 massive star-forming galaxies (SFGs) and 12 weak AGN with reliably measured spectroscopic redshifts at z≃ 2.3{--}4.1. We analyzed Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) mosaics of the Early Release Science (ERS) field in three UVIS filters to sample the re…
Size of a plasma cloud matters. The polarisation electric field of a small-scale comet ionosphere
Gunell, H.; Behar, E.; Nilsson, H. +7 more
Context. The cometary ionosphere is immersed in fast flowing solar wind. A polarisation electric field may arise for comets much smaller than the gyroradius of pickup ions because ions and electrons respond differently to the solar wind electric field.
Aims: A situation similar to that found at a low activity comet has been modelled for bariu…
An ALMA Survey of the SCUBA-2 Cosmology Legacy Survey UKIDSS/UDS Field: Identifying Candidate z ∼ 4.5 [C II] Emitters
Thomson, A. P.; Scott, D.; Smail, Ian +18 more
We report the results of a search for serendipitous [C II] 157.74 µm emitters at z ≃ 4.4-4.7 using the Atacama Large Millimeter/submillimeter Array (ALMA). The search exploits the AS2UDS continuum survey, which covers ∼50 arcmin2 of the sky toward 695 luminous (S 870 ≳ 1 mJy) submillimeter galaxies (SMGs), selected from…
Resolving faint structures in the debris disk around TWA 7. Tentative detections of an outer belt, a spiral arm, and a dusty cloud
Pinte, C.; Ménard, F.; Augereau, J. -C. +51 more
Context. Debris disks are the intrinsic by-products of the star and planet formation processes. Most likely due to instrumental limitations and their natural faintness, little is known about debris disks around low mass stars, especially when it comes to spatially resolved observations.
Aims: We present new VLT/SPHERE IRDIS dual-polarization …
Evidence of a truncated spectrum in the angular correlation function of the cosmic microwave background
López-Corredoira, M.; Melia, F.
Aim. The lack of large-angle correlations in the fluctuations of the cosmic microwave background (CMB) conflicts with predictions of slow-roll inflation. But while probabilities (≲0.24%) for the missing correlations disfavour the conventional picture at ≳3σ, factors not associated with the model itself may be contributing to the tension. Here we a…
The Warm Neptunes around HD 106315 Have Low Stellar Obliquities
Vanderburg, Andrew; Bieryla, Allyson; Latham, David W. +8 more
We present the obliquity of the warm Neptune HD 106315c measured via a series of spectroscopic transit observations. HD 106315c is a 4.4 R Earth warm Neptune orbiting a moderately rotating late F star with a period of 21.05 days. HD 106315 also hosts a 2.5 R Earth super-Earth on a 9.55 day orbit. Our Doppler tomographic analy…
A New Test of Copper and Zinc Abundances in Late-type Stars Using Ultraviolet Cu II and Zn II Lines
Roederer, Ian U.; Barklem, Paul S.
We present new abundances derived from Cu I, Cu II, Zn I, and Zn II lines in six warm (5766 ≤ {T}eff} ≤ 6427 K), metal-poor (-2.50 ≤ [Fe/H] ≤ -0.95) dwarf and subgiant (3.64 ≤ log g ≤ 4.44) stars. These abundances are derived from archival high-resolution ultraviolet spectra from the Space Telescope Imaging Spectrograph on board the Hub…