scholarly journals VERTICAL ATMOSPHERIC STRUCTURE IN A VARIABLE BROWN DWARF: PRESSURE-DEPENDENT PHASE SHIFTS IN SIMULTANEOUS HUBBLE SPACE TELESCOPE - SPITZER LIGHT CURVES

2012 ◽  
Vol 760 (2) ◽  
pp. L31 ◽  
Author(s):  
Esther Buenzli ◽  
Dániel Apai ◽  
Caroline V. Morley ◽  
Davin Flateau ◽  
Adam P. Showman ◽  
...  
Keyword(s):  
Hubble Space Telescope ◽  
Phase Shifts ◽  
Light Curves ◽  
Brown Dwarf ◽  
Space Telescope ◽  
Atmospheric Structure

scholarly journals Surveying the Solar Neighborhood for Brown Dwarf Companions with the ECLIPSE Discovery Mission

2003 ◽  
Vol 211 ◽  
pp. 523-524
Author(s):  
Karl Stapelfeldt
Keyword(s):  
Luminosity Function ◽  
Hubble Space Telescope ◽  
Scattered Light ◽  
Solar Neighborhood ◽  
Brown Dwarf ◽  
Space Telescope ◽  
Effective Temperatures

The proposed Eclipse Discovery mission is an optical space telescope designed to provide a thousandfold reduction in scattered light near bright stars in comparison to any Hubble Space Telescope instrument. A survey of 500 single stars within 15 pc can detect companions with absolute z magnitude of 22 at separations > 10 AU in most of the targets. Spectrophotometry of CH4 and H2O bands between 0.8-1.0 μm can be used to derive the effective temperatures of the objects. The ECLIPSE brown dwarf survey would directly measure the luminosity function of brown dwarf companions down to ~20 Jupiter masses, providing a crucial comparison with field objects.

scholarly journals The Y dwarf population with HST: unlocking the secrets of our coolest neighbours – I. Overview and first astrometric results

2020 ◽  
Vol 501 (1) ◽  
pp. 911-915
Author(s):  
C Fontanive ◽  
L R Bedin ◽  
D C Bardalez Gagliuffi
Keyword(s):  
Proper Motion ◽  
Hubble Space Telescope ◽  
Proper Motions ◽  
Brown Dwarf ◽  
Space Telescope ◽  
First Results

ABSTRACT In this paper, we present our project that aims at determining accurate distances and proper motions for the Y brown dwarf population using the Hubble Space Telescope. We validate the program with our first results, using a single new epoch of observations of the Y0pec dwarf WISE J163940.83−684738.6. These new data allowed us to refine its proper motion and improve the accuracy of its parallax by a factor of three compared to previous determinations, now constrained to ϖ = 211.11 ± 0.56 mas. This newly derived absolute parallax corresponds to a distance of 4.737 ± 0.013 pc, an exquisite and unprecedented precision for faint ultracool Y dwarfs.

scholarly journals Hubble Space Telescope NICMOS Observations of T Dwarfs: Brown Dwarf Multiplicity and New Probes of the L/T Transition

2006 ◽  
Vol 166 (2) ◽  
pp. 585-612 ◽  
Author(s):  
Adam J. Burgasser ◽  
J. Davy Kirkpatrick ◽  
Kelle L. Cruz ◽  
I. Neill Reid ◽  
Sandy K. Leggett ◽  
...  
Keyword(s):  
Hubble Space Telescope ◽  
Brown Dwarf ◽  
Space Telescope

scholarly journals The mid-infrared Leavitt law for classical Cepheids in the Magellanic Clouds

2020 ◽  
Vol 500 (1) ◽  
pp. 817-837
Author(s):  
Abigail H Chown ◽  
Victoria Scowcroft ◽  
Stijn Wuyts
Keyword(s):  
Hubble Space Telescope ◽  
Zero Point ◽  
Large Magellanic Cloud ◽  
Magellanic Clouds ◽  
Light Curves ◽  
Log P ◽  
Mid Infrared ◽  
Space Telescope ◽  
Classical Cepheids ◽  
Combining Data

ABSTRACT The Cepheid Leavitt Law (LL), also known as the Period–Luminosity relation, is a crucial tool for assembling the cosmic distance ladder. By combining data from the OGLE-IV catalogue with mid-infrared photometry from the Spitzer Space Telescope, we have determined the 3.6 and 4.5 $\mu$m LLs for the Magellanic Clouds using ∼5000 fundamental-mode classical Cepheids. Mean magnitudes were determined using a Monte Carlo Markov Chain (MCMC) template fitting procedure, with template light curves constructed from a subsample of these Cepheids with fully phased, well-sampled light curves. The dependence of the Large Magellanic Cloud LL coefficients on various period cuts was tested, in addition to the linearity of the relationship. The zero-point of the LL was calibrated using the parallaxes of Milky Way Cepheids from the Hubble Space Telescope and Gaia Data Release 2. Our final calibrated relations are M[3.6] = −3.246(±0.008)(log (P) − 1.0) − 5.784(±0.030) and M[4.5] = −3.162(±0.008)(log (P) − 1.0) − 5.751(±0.030).

scholarly journals Hubble Space Telescope astrometry of the closest brown dwarf binary system – I. Overview and improved orbit★

2017 ◽  
Vol 470 (1) ◽  
pp. 1140-1155 ◽  
Author(s):  
L. R. Bedin ◽  
D. Pourbaix ◽  
D. Apai ◽  
A. J. Burgasser ◽  
E. Buenzli ◽  
...  
Keyword(s):  
Binary System ◽  
Hubble Space Telescope ◽  
Brown Dwarf ◽  
Space Telescope

scholarly journals THE COLLAPSE OF THE WIEN TAIL IN THE COLDEST BROWN DWARF? HUBBLE SPACE TELESCOPE NEAR-INFRARED PHOTOMETRY OF WISE J085510.83–071442.5

2016 ◽  
Vol 823 (2) ◽  
pp. L35 ◽  
Author(s):  
Adam C. Schneider ◽  
Michael C. Cushing ◽  
J. Davy Kirkpatrick ◽  
Christopher R. Gelino
Keyword(s):  
Near Infrared ◽  
Hubble Space Telescope ◽  
Infrared Photometry ◽  
Brown Dwarf ◽  
Space Telescope

scholarly journals The hydrogen exosphere of exoplanet HD 209458b detected with HST/ACS

2008 ◽  
Vol 4 (S253) ◽  
pp. 528-531
Author(s):  
D. Ehrenreich ◽  
A. Lecavelier des Etangs ◽  
G. Hébrard ◽  
J.-M. Désert ◽  
A. Vidal-Madjar ◽  
...  
Keyword(s):  
Atomic Hydrogen ◽  
Hubble Space Telescope ◽  
Light Curves ◽  
Extrasolar Planet ◽  
Space Telescope ◽  
Advanced Camera For Surveys ◽  
In Transit ◽  
Observational Signature ◽  
Good Agreement

AbstractExospheric atomic hydrogen escaping from the planet HD 209458b provides the largest observational signature ever detected for an extrasolar planet atmosphere. We present observations of this transiting planet's extended exosphere with the Advanced Camera for Surveys on board the Hubble Space Telescope. From the two transit light curves obtained at Lyman α, we find an in-transit absorption of (8.0±5.7)%, in good agreement with previous studies. These new constraints on the size of the exosphere strengthens the evaporation scenario. Full details are provided in Ehrenreich et al. (2008).

Hubble Space Telescope/Faint Object Spectrograph Imaging of Wolf 424 AB: Is This Binary a Double Brown Dwarf System?

1998 ◽  
Vol 110 (743) ◽  
pp. 31-38 ◽  
Author(s):  
A. B. Schultz ◽  
H. M. Hart ◽  
J. L. Hershey ◽  
F. C. Hamilton ◽  
M. Kochte ◽  
...  
Keyword(s):  
Hubble Space Telescope ◽  
Brown Dwarf ◽  
Space Telescope ◽  
Faint Object ◽  
Faint Object Spectrograph

scholarly journals Unseen companions of V Hya inferred from periodic ejections

2019 ◽  
Vol 487 (3) ◽  
pp. 3029-3036 ◽  
Author(s):  
Jesus M Salas ◽  
Smadar Naoz ◽  
Mark R Morris ◽  
Alexander P Stephan
Keyword(s):  
Orbital Period ◽  
Triple System ◽  
High Speed ◽  
Hubble Space Telescope ◽  
Eccentric Orbit ◽  
Brown Dwarf ◽  
High Eccentricity ◽  
Distant Object ◽  
Space Telescope ◽  
Ejection Mechanism

ABSTRACT A recent study using Hubble Space Telescope observations found periodic, high-speed, collimated ejections (or ‘bullets’) from the star V Hya. The authors of that study proposed a model associating these bullets with the periastron passage of an unseen, substellar companion in an eccentric orbit and with an orbital period of ∼8 yr. Here we propose that V Hya is part of a triple system, with a substellar companion having an orbital period of ∼8 yr, and a tertiary object on a much wider orbit. In this model, the more distant object causes high-eccentricity excitations on the substellar companion’s orbit via the Eccentric Kozai–Lidov mechanism. These eccentricities can reach such high values that they lead to Roche-lobe crossing, producing the observed bullet ejections via a strongly enhanced accretion episode. For example, we find that a ballistic bullet ejection mechanism can be produced by a brown-dwarf-mass companion, while magnetically driven outflows are consistent with a Jovian-mass companion. Finally, we suggest that the distant companion may reside at few a hundred astronomical units on an eccentric orbit.

scholarly journals Extending Gaia  DR2 with HST  narrow-field astrometry – II. Refining the method on WISE J163940.83−684738.6★

2020 ◽  
Vol 494 (2) ◽  
pp. 2068-2075
Author(s):  
L R Bedin ◽  
C Fontanive
Keyword(s):  
High Precision ◽  
Reference System ◽  
Hubble Space Telescope ◽  
High Accuracy ◽  
Test Case ◽  
Wide Field ◽  
Brown Dwarf ◽  
Space Telescope ◽  
Infra Red ◽  
Gaia Dr2

ABSTRACT In the second paper of this series, we perfected our method of linking high-precision Hubble Space Telescope astrometry to the high-accuracy Gaia DR2 absolute reference system to overcome the limitations of relative astrometry with narrow-field cameras. Our test case here is the Y brown dwarf WISE  J163940.83−684738.6, observed at different epochs spread over a 6-yr time baseline with the Infra-Red channel of the Wide Field Camera 3. We derived significantly improved astrometric parameters compared to previous determinations, finding (μαcos δ, μδ, ϖ) = (577.21 ± 0.24 mas yr−1, −3108.39 ± 0.27 mas yr−1, 210.4 ± 1.8 mas). In particular, our derived absolute parallax (ϖ ) corresponds to a distance of 4.75 ± 0.05 pc for the faint ultracool dwarf.

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