130 citations · 649 across the 28 of their papers we have counts for
21 papers · 1 filter
First L-type substellar object discovered in the vicinity of the embedded cluster NGC 2023
Styliani Tsilia, Carlos Dominguez-Tagle, Maruša Žerjal +8
We present the first substellar object in a star-forming region spectroscopically confirmed with Euclid, namely J054158.70-021031.4. This young and faint source is located close to…
JWST Observations of the Metal-poor T Dwarf WISEA J155349.96+693355.2: The First Brown Dwarf Associated with the Gaia-Enceladus Milky Way Substructure
Aaron M. Meisner, Adam J. Burgasser, Chih-Chun Hsu +15
We present JWST NIRSpec and MIRI observations of the metal-poor T dwarf WISEA J155349.96+693355.2. The combined NIRSpec/prism plus MIRI/LRS spectrum (R ~ 100) provides 0.6-12 m…
Metal-poor Brown Dwarf Kinematics from JWST NIRSpec Spectroscopy
Chih-Chun Hsu, Christopher A. Theissen, Adam J. Burgasser +14
Galactic archaeology relies on stellar kinematics and chemical abundances to identify various stellar populations and associations. With JWST, Galactic archaeology of ancient metal…
Halo stars harbour few wide ultracool companions
Jerry Jun-Yan Zhang, Nicolas Lodieu, Eduardo L. Martín
We conducted the first search for wide ultracool companions to metal-poor halo stars. A sample of nearby halo stars with spectroscopically determined metallicities and high proper…
Observation of undepleted phosphine in the atmosphere of a low-temperature brown dwarf
Adam J. Burgasser, Eileen C. Gonzales, Samuel A. Beiler +16
The atmospheres of low-temperature brown dwarfs and gas giant planets are expected to contain the phosphine molecule, PH However, previous observations have shown much lower ab…
-band photometry of the Extreme T Subdwarf CWISE J221706.28145437.6
Jerry Jun-Yan Zhang, Nicolas Lodieu, Eduardo L. Martín
We present deep -band imaging of the extreme T subdwarf CWISE J221706.28145437.6. Using the new photometry, we construct its spectral energy distribution and find this obje…
Euclid Quick Data Release (Q1) Ultracool dwarfs in the Euclid Deep Field North
A. Mohandasan, R. L. Smart, C. Reylé +176
Ultracool dwarfs (UCDs) encompass the lowest mass stars and brown dwarfs, defining the stellar substellar boundary. They have significant potential for advancing the understanding…
Detection of Methane in the Closest Extreme Metal-poor T Dwarf WISEA J181006.18-101000.5
Jerry Jun-Yan Zhang, Nicolas Lodieu, Eduardo L. Martín +7
WISEA J181006.18-101000.5 (WISE1810) is the nearest metal-poor ultracool dwarf to the Sun. It has a low effective temperature and has been classified as extreme early-T subdwarf. H…
Euclid: Quick Data Release (Q1) -- A photometric search for ultracool dwarfs in the Euclid Deep Fields
M. Žerjal, C. Dominguez-Tagle, N. Vitas +178
We present a catalogue of 5306 new ultracool dwarf (UCD) candidates in the three Euclid Deep Fields in the Q1 data release. They range from late M to late T dwarfs, and include 120…
Euclid Quick Data Release (Q1) -- Spectroscopic search, classification and analysis of ultracool dwarfs in the Deep Fields
C. Dominguez-Tagle, M. Žerjal, N. Sedighi +14
The Near-Infrared Spectrometer and Photometer onboard the Euclid space mission has obtained near-infrared (NIR) slitless spectra of millions of objects, including hundreds of ultra…
Optical constraints on the coldest metal-poor population
Jerry Jun-Yan Zhang, Nicolas Lodieu, Eduardo L. Martín +10
The coldest metal-poor population made of T and Y dwarfs are archaeological tracers of our Galaxy because they are very old and have kept the pristine material. The optical propert…
Reconnaissance ultracool spectra in the Euclid Deep Fields
Jerry Jun-Yan Zhang, Nicolas Lodieu, Eduardo Martín
Context. Euclid will carry out a deep survey benefiting the discovery and characterisation of ultracool dwarfs (UCDs), especially in the Euclid Deep Fields (EDFs), which the telesc…
CARMENES input catalog of M dwarfs: VII. New rotation periods for the survey stars and their correlations with stellar activity
Yutong Shan, Daniel Revilla, Sebastian L. Skrzypinski +40
Abridged: We measured photometric and spectroscopic for a large sample of nearby bright M dwarfs with spectral types from M0 to M9, as part of our continual effort to…
Stellar Astrophysics and Exoplanet Science with the Maunakea Spectroscopic Explorer (MSE)
Maria Bergemann, Daniel Huber, Vardan Adibekyan +70
The Maunakea Spectroscopic Explorer (MSE) is a planned 11.25-m aperture facility with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. A…
Metal-Depleted Brown Dwarfs
Nicolas Lodieu
This chapter reviews our current knowledge of metal-poor ultracool dwarfs with spectral types later than M7. The current census of M, L, and T subdwarfs is explored. The main colou…
Flare activity and photospheric analysis of Proxima Centauri
Ya. V. Pavlenko, A. Suarez Mascareno, R. Rebolo +3
We present the analysis of emission lines in high-resolution optical spectra of the planet-host star Proxima Centauri (Proxima) classified as a M5.5V\@. We carry out the detailed a…
Discovery of wide low and very low-mass binary systems using Virtual Observatory tools
M. C. Galvez-Ortiz, E. Solano, N. Lodieu +1
The frequency of multiple systems and their properties are key constraints of stellar formation and evolution. Formation mechanisms of very low-mass (VLM) objects are still under c…
An eclipsing double-line spectroscopic binary at the stellar/substellar boundary in the Upper Scorpius OB association
N. Lodieu, R. Alonso, J. I. Gonzalez Hernandez +12
We aim at constraining evolutionary models at low mass and young ages by identifying interesting transiting system members of the nearest OB association to the Sun, Upper Scorpius,…
New ultracool subdwarfs identified in large-scale surveys using Virtual Observatory tools: Part I: UKIDSS LAS DR5 vs SDSS DR7
N. Lodieu, M. Espinoza Contreras, M. R. Zapatero Osorio +3
The aim of the project is to improve our knowledge on the low-mass and low-metallicity population to investigate the influence of metallicity of the stellar (and substellar) mass f…
Low Mass Stars and Brown Dwarfs in Praesepe
D. E. A. Baker, R. F. Jameson, S. L. Casewell +3
Presented are the results of a large and deep optical-near-infrared multi-epoch survey of the Praesepe open star cluster using data from the UKIDSS Galactic Clusters Survey. Multip…
Epsilon Indi Ba, Bb: a detailed study of the nearest known brown dwarfs
Robert R. King, Mark J. McCaughrean, Derek Homeier +3
The discovery of epsilon Indi Ba, Bb, a binary brown dwarf system very close to the Sun, makes possible a concerted campaign to characterise the physical parameters of two T dwarfs…