English
Related papers

Related papers: Radio Constraints on Activity in Young Brown Dwarf…

200 papers

We report on the first dedicated monitoring campaign of spectroscopic variability in young brown dwarfs. High-resolution optical spectra of six targets in nearby star-forming regions were obtained over 11 nights between 2005 January-March…

Astrophysics · Physics 2009-11-13 Alexander Scholz , Ray Jayawardhana

Aims. With the aim to reveal the effects of the magnetic field to the multi-band activity of dwarf stars, we search for associated radio emission for an extensive list of 14 915 brown dwarfs and 15 124 flaring stars. Methods. We utilised…

Solar and Stellar Astrophysics · Physics 2025-06-30 K. Perger , B. Seli , K. Vida

*Abbreviated abstract* Context: Brown dwarfs in the spectral range L9-T3.5, within the so called L/T transition, have been shown to be variable at higher amplitudes and with greater frequency than other field dwarfs. [...] Now, more…

Earth and Planetary Astrophysics · Physics 2019-11-04 Simon C. Eriksson , Markus Janson , Per Calissendorff

We have used the VLA to conduct a deep search for 3.6 cm radio emission from nearby very low mass stars and brown dwarfs. The Gudel-Benz relation is used to predict radio luminosities for some very low mass stars and candidate brown dwarfs…

Astrophysics · Physics 2009-10-31 Anita Krishnamurthi , Giuseppe Leto , Jeffrey L. Linsky

We report the detection of H{$\alpha$} emission in the T dwarf (methane brown dwarf) 2MASSW J1237392+652615 over three days using the Keck Low Resolution Imaging Spectrograph. The measured line flux, log(L$_{H{\alpha}}$/L$_{bol}$) = $-$4.3,…

We have identified four brown dwarfs in the Taurus star-forming region. They were first selected from $R$ and $I$ CCD photometry of 2.29 square degrees obtained at the Canada-France-Hawaii Telescope. Subsequently, they were recovered in the…

Astrophysics · Physics 2011-02-11 E. L. Martin , C. Dougados , E. Magnier , F. Menard , A. Magazzu , J. -C. Cuillandre , X. Delfosse

We observed with the JVLA at 3.6 and 1.3 cm a sample of 11 proto-brown dwarf candidates in Taurus in a search for thermal radio jets driven by the most embedded brown dwarfs. We detected for the first time four thermal radio jets in…

We present the results of a HST/NICMOS coronagraphic survey for the direct detection of substellar companions within the young TW Hydrae and Tucana Associations. At the distance of these associations, the lower mass limit of detection,…

The census of young moving groups in the solar neighborhood is significantly incomplete in the low-mass regime. We have developed a new selection process to find these missing members based on the GALEX All-Sky Imaging Survey. For stars…

Solar and Stellar Astrophysics · Physics 2015-05-20 Evgenya L. Shkolnik , Michael C. Liu , Iain Neill Reid , Trent Dupuy , Alycia Weinberger

We report the discovery of the youngest brown dwarf with a disk at 102 pc from the Sun, WISEA~J120037.79-784508.3 (W1200-7845), via the Disk Detective citizen science project. We establish that W1200-7845 is located in the…

We present new radial velocity (RV) measurements for 11 candidate young very-low-mass stars and brown dwarfs, with spectral types from M7 to L7. Candidate young objects were identified by features indicative of low surface gravity in their…

The paper presents the results of multi-wave radio observations of sixteen red dwarfs with Earth-like planets in the habitable zones on RATAN-600. In the passage mode, radiometers of four frequency ranges of 22, 11, 4.7 and 2.3 GHz (1.38,…

Solar and Stellar Astrophysics · Physics 2025-05-21 Grigory M. Beskin , Vladimir N. Chernenkov , Nikolai N. Bursov , Alexey A. Shlyapnikov , Alexander D. Panov

We have measured a trigonometric parallax to the young brown dwarf 2MASSW J1207334-393254. The distance [54.0 (+3.2,-2.8) pc] and space motion confirm membership in the TW Hydrae Association. The primary is a ~25 M_jup brown dwarf. We…

Astrophysics · Physics 2009-11-13 John E. Gizis , Wei-Chun Jao , John P. Subasavage , Todd J. Henry

We present low-resolution Keck I/LRIS spectra spanning from 3200-9000 A of nine young brown dwarfs and three low-mass stars in the TW Hya Association and in Upper Sco. The optical spectral types of the brown dwarfs range from M5.5-M8.75,…

Solar and Stellar Astrophysics · Physics 2009-11-13 Gregory J. Herczeg , Kelle L. Cruz , Lynne A. Hillenbrand

We present the detection of the binary system 2MASS J02132062+3648506 AB using the Karl G. Jansky Very Large Array (VLA) archive data observed at 4-8 GHz. The system is a triple consisting of a tight binary ($\sim0.2"$) of two M dwarfs of…

We report on a sequence of Chandra X-ray Observatory observations of the TW Hydrae brown dwarf (BD) 2MASSW J1139511-315921 (2M1139). In the combined 31 ks ACIS-S exposure, 2M1139 is detected at the 3-sigma confidence level. We find an X-ray…

Solar and Stellar Astrophysics · Physics 2015-05-28 Philip J. Castro , John E. Gizis , Marc Gagné

Mapping out the populations of thick disk and halo brown dwarfs is important for understanding the metallicity dependence of low-temperature atmospheres and the substellar mass function. Recently, a new population of cold and metal-poor…

Solar and Stellar Astrophysics · Physics 2023-07-19 A. M. Meisner , S. K. Leggett , S. E. Logsdon , A. C. Schneider , P. Tremblin , M. Phillips

We conducted a search for brown dwarf candidates in a James Webb Space Telescope deep field around A2744 to investigate the space density of these objects at kiloparsec distances. Our methodology employed an initial selection based on…

Solar and Stellar Astrophysics · Physics 2026-02-17 D. H. Li , Z. H. Zhang , H. H. Peng , M. C. Galvez-Ortiz , S. Y. Zhou , H. R. A. Jones

Brown dwarfs display Jupiter-like auroral phenomena, such as rotationally modulated electron cyclotron maser radio emission. Radio observations of cyclotron maser emission can be used to measure their magnetic field strength, topology, and…

Solar and Stellar Astrophysics · Physics 2025-10-30 Timothy W. H. Yiu , Harish K. Vedantham , Joseph R. Callingham , Timothy W. Shimwell

From a series of 5 GHz VLBA radio observations taken over 1-yr span, we present the detection of compact highly-polarized radio emission from the T6 brown dwarf WISE J112254.72+255022.2 compatible with electron cyclotron maser emission.…

Solar and Stellar Astrophysics · Physics 2025-05-08 J. C. Guirado , J. B. Climent , J. D. Bergasa , M. A. Pérez-Torres , J. M. Marcaide , L. Peña-Moñino