Search Publications
Characterization of the known T-type dwarfs towards the σ Orionis cluster
Béjar, V. J. S.; Zapatero Osorio, M. R.; Peña Ramírez, K.
Aims: The detailed study of T-type candidate members of the young σ Orionis cluster (~3 Myr, ~352 pc, solar metallicity) is fundamental to properly assess the objects' cluster membership and their contribution to the definition of the substellar mass function.
Methods: A total of three T-type candidates (S Ori 70, S Ori 73, and S Ori J05…
On the Binary Frequency of the Lowest Mass Members of the Pleiades with Hubble Space Telescope Wide Field Camera 3
Dupuy, Trent J.; Liu, Michael C.; Deacon, Niall R. +2 more
We present the results of a Hubble Space Telescope Wide Field Camera 3 (WFC3) imaging survey of 11 of the lowest mass brown dwarfs in the Pleiades known (25-40 MJup). These objects represent the predecessors to T dwarfs in the field. Using a semi-empirical binary point-spread function (PSF)-fitting technique, we are able to probe to 0.″…
Signatures of the very early Universe: Inflation, spatial curvature, and large scale anomalies
Aslanyan, Grigor; Easther, Richard
A short inflationary phase may not erase all traces of the primordial Universe. Associated observables include both spatial curvature and "anomalies" in the microwave background or large-scale structure. The present curvature ΩK ,0 reflects the initial curvature, ΩK ,start , and the angular size of anomalies depends on k…
Current sheets with inhomogeneous plasma temperature: Effects of polarization electric field and 2D solutions
Artemyev, A. V.; Vasko, I. Y.; Zimbardo, G. +1 more
We develop current sheet models which allow to regulate the level of plasma temperature and density inhomogeneities across the sheet. These models generalize the classical Harris model via including two current-carrying plasma populations with different temperature and the background plasma not contributing to the current density. The parameters o…
Search for horizontal and vertical variations of CO in the day and night side lower mesosphere of Venus from CSHELL/IRTF 4.53 µm observations
Bertaux, Jean-Loup; Lellouch, Emmanuel; Marcq, Emmanuel +3 more
High-resolution (R ~ 43 , 000) spectroscopic observations of both day and night sides of Venus were acquired using CSHELL at IRTF between 2202 and 2207cm-1 (4.53- 4.54 µm) during the latest maximal eastern and western elongations of Venus in two four-nights observing runs in August 2012 and November 2013. Their purpose was to inve…
The variability behaviour of CoRoT M-giant stars⋆
Baglin, A.; Paz-Chinchón, F.; Janot-Pacheco, E. +8 more
Context. For six years the Convection, Rotation, and planetary Transits (CoRoT) space mission has been acquiring photometric data from more than 100 000 point sources towards and directly opposite the inner and outer regions of the Galaxy. The high temporal resolution of the CoRoT data, combined with the wide time span of the observations, enabled…
Subaru and Swift observations of V652 Herculis: resolving the photospheric pulsation
Starling, R. L. C.; Jeffery, C. S.; McCormac, J. +4 more
High-resolution spectroscopy with the Subaru High Dispersion Spectrograph, and Swift ultraviolet photometry are presented for the pulsating extreme helium star V652 Her. Swift provides the best relative ultraviolet photometry obtained to date, but shows no direct evidence for a shock at ultraviolet or X-ray wavelengths. Subaru has provided high sp…
Direct observation of the energy release site in a solar flare by SDO/AIA, Hinode/EIS, and RHESSI
Fletcher, L.; Simões, P. J. A.; Graham, D. R.
Aims: We present direct evidence of the detection of the main energy release site in a non-eruptive solar flare, SOL2013-11-09T06:38 UT. This GOES class C2.6 event was characterised by two flaring ribbons and a compact, bright coronal source located between them, which is the focus of our study.
Methods: We use imaging from SDO/AIA, and …
Disentangling the outflow and protostars in HH 900 in the Carina Nebula
Anderson, Jay; Smith, Nathan; Bally, John +2 more
HH 900 is a peculiar protostellar outflow emerging from a small, tadpole-shaped globule in the Carina Nebula. Previous Hα imaging with Hubble Space Telescope (HST)/Advanced Camera for Surveys showed an ionized outflow with a wide opening angle that is distinct from the highly collimated structures typically seen in protostellar jets. We present ne…
Witness of gas infall and outflow in the young starburst dwarf galaxy NGC 5253
Hirota, Akihiko; Nakanishi, Kouichiro; Espada, Daniel +2 more
We present 12CO(2-1) observations towards the dwarf galaxy NGC 5253 using the Submillimeter Array. The data shows that a large amount of molecular gas is located in the central ∼ 200 pc starburst region, physically associated with two young super stellar clusters (SSCs). The molecular gas traced by 12CO(2-1) is elongated alon…