Results 31 to 40 of about 238,136 (265)

Occurrence Rate of Hot Jupiters Around Early-type M Dwarfs Based on Transiting Exoplanet Survey Satellite Data

The Astronomical Journal, 2022
We present an estimate of the occurrence rate of hot Jupiters (7 R _⊕ ≤ R _p ≤ 2 R _J , 0.8 ≤ P _b ≤ 10 days) around early-type M dwarfs based on stars observed by the Transiting Exoplanet Survey Satellite (TESS) during its primary mission.
Tianjun Gan, Sharon X. Wang, Songhu Wang, Shude Mao, Chelsea X. Huang, Karen A. Collins, Keivan G. Stassun, Avi Shporer, Wei Zhu, George R. Ricker, Roland Vanderspek, David W. Latham, Sara Seager, Joshua N. Winn, Jon M. Jenkins, Khalid Barkaoui, Alexander A. Belinski, David R. Ciardi, Phil Evans, Eric Girardin, Nataliia A. Maslennikova, Tsevi Mazeh, Aviad Panahi, Francisco J. Pozuelos, Don J. Radford, Richard P. Schwarz, Joseph D. Twicken, Anaël Wünsche, Shay Zucker   +28 more
doaj   +1 more source

The ultracool-field dwarf luminosity-function and space density from the Canada-France Brown Dwarf Survey [PDF]

, 2010
Context. Thanks to recent and ongoing large scale surveys, hundreds of brown dwarfs have been discovered in the last decade. The Canada-France Brown Dwarf Survey is a wide-field survey for cool brown dwarfs conducted with the MegaCam camera on the Canada-France-Hawaii Telescope telescope. Aims.
arxiv   +1 more source

A Cross-Match of 2MASS and SDSS. II. Peculiar L Dwarfs, Unresolved Binaries, and the Space Density of T Dwarf Secondaries [PDF]

, 2011
We present the completion of a program to cross-correlate the SDSS Data Release 1 and 2MASS Point Source Catalog in search for extremely red L and T dwarfs. The program was initiated by Metchev and collaborators, who presented the findings on all newly identified T dwarfs in SDSS DR1, and estimated the space density of isolated T0--T8 dwarfs in the ...
arxiv   +1 more source

Seventy-One New L and T Dwarfs from the Sloan Digital Sky Survey [PDF]

Astron.J.131:2722-2736,2006, 2006
We present near-infrared observations of 71 newly discovered L and T dwarfs, selected from imaging data of the Sloan Digital Sky Survey (SDSS) using the i-dropout technique. Sixty-five of these dwarfs have been classified spectroscopically according to the near-infrared L dwarf classification scheme of Geballe et al.
arxiv   +1 more source

An Examination of Aerosol Jet‐Printed Surface Roughness and its Impact on the Performance of High‐Frequency Electronics

Advanced Engineering Materials, EarlyView.
This study explores aerosol jet‐printed (AJP) surface roughness, its effects on the performance of microwave electronics, and its process contributors. First, an electromagnetic model is vetted for AJP's unique roughness signature. Simulations are built which show process‐induced roughness is as significant as conductor resistivity in driving microwave
Christopher Areias, Alkim Akyurtlu
wiley   +1 more source

Finding ultracool brown dwarfs with MegaCam on CFHT: method and first results [PDF]

, 2008
We present the first results of a wide field survey for cool brown dwarfs with the MegaCam camera on the CFHT telescope, the Canada-France Brown Dwarf Survey, hereafter CFBDS. Our objectives are to find ultracool brown dwarfs and to constrain the field-brown dwarf mass function thanks to a larger sample of L and T dwarfs. We identify candidates in CFHT/
arxiv   +1 more source

Inter‐Layer Diffusion of Excitations in 2D Perovskites Revealed by Photoluminescence Reabsorption

Advanced Functional Materials, EarlyView.
Inter‐layer diffusion of photoexcitations is monitored in thin films of the 2D perovskite (PEA)2PbI4 by tracking time‐dependent changes in photoluminescence spectra induced by photon reabsorption effects. A low out‐of‐plane excitation diffusion coefficient of 0.26 × 10−4 cm2 s−1 is determined through 1D diffusion modeling.
Jiaxing Du, Marcello Righetto, Manuel Kober‐Czerny, Siyu Yan, Karim A. Elmestekawy, Henry J. Snaith, Michael B. Johnston, Laura M. Herz   +7 more
wiley   +1 more source

Exciton Dynamics in Layered Halide Perovskite Light‐Emitting Diodes

Advanced Materials, EarlyView.
This review discusses the exciton dynamics in layered halide perovskitelight‐emitting diodes (PeLEDs). It opens with a summary of the structural and photophysical aspects, followed by an exploration of controlling dimensionality and cascade exciton transfer in quasi‐2D PeLEDs.
Sung‐Doo Baek, Seok Joo Yang, Hanjun Yang, Wenhao Shao, Yu‐Ting Yang, Letian Dou   +5 more
wiley   +1 more source

Physical Parameters and Properties of 20 Cold Brown Dwarfs in JWST

The Astrophysical Journal
We present a comprehensive analysis of 20 T and Y dwarfs using spectroscopy from the Near-Infrared Spectrograph (NIRSpec) CLEAR/PRISM and Mid-Infrared Instrument (MIRI) low-resolution spectrometer instruments on the James Webb Space Telescope.
Zhijun Tu, Shu Wang, Jifeng Liu
doaj   +1 more source

Sustainable Sensors Prepared by Environmentally Benign Means for Improving the Environmental Footprint of Wearable Electronics

Advanced Materials Technologies, EarlyView.
A stretchable and bendable resistance sensor made predominantly from sustainable and biodegradable components is conductive courtesy a water soluble self‐doped conjugated polymer. The wearable sensor measures micromovements by changes in its resistance and it can track both human movement and phonation. Abstract Sustainable electronic devices offer the
Cephas Amoah, Usmaan Mahmood, W. G. Skene   +2 more
wiley   +1 more source