Results 41 to 50 of about 87,580 (344)

Weather on Other Worlds. II. Survey Results: Spots Are Ubiquitous on L and T Dwarfs

, 2014
We present results from the "Weather on Other Worlds" Spitzer Exploration Science program to investigate photometric variability in L and T dwarfs, usually attributed to patchy clouds.
Apai, Dániel, Artigau, Étienne, Burgasser, Adam, Flateau, Davin, Goldman, Bertrand, Heinze, Aren, Marley, Mark S., Metchev, Stanimir, Plavchan, Peter, Radigan, Jacqueline   +9 more
core   +1 more source

Towards Spectral Classification of L and T Dwarfs: Infrared and Optical Spectroscopy and Analysis [PDF]

, 2001
We present 0.6-2.5um, R~400 spectra of twenty-seven cool, low luminosity stars and substellar objects. Based on these and previously published spectra we develop a preliminary spectral classification system for L and T dwarfs.
Anderson, S, Brinkmann, J, Csabai, I, Fan, X, Geballe, T R, Golimowski, D A, Gunn, J E, Hawley, S L, Hennessy, G, Henry, T J, Hill, G J, Hindsley, R B, Ivezic, Z, Knapp, G R, Leggett, S K, Lupton, R H, Mcdaniel, A, Munn, J A, Narayanan, V K, Peng, E, Pier, J R, Rockosi, C M, Schneider, D P, Smith, J A, Strauss, M A, Tsvetanov, Z I, Uomoto, A, York, D G, Zheng, W   +28 more
core   +2 more sources

Searching for benchmark systems containing ultra-cool dwarfs and white dwarfs

EPJ Web of Conferences, 2013
We have used the 2MASS all-sky survey and WISE to look for ultracool dwarfs that are part of multiple systems containing main sequence stars. We cross-matched L dwarf candidates from the surveys with Hipparcos and Gliese stars, finding two new systems ...
Pinfield D.J., Gomes J.I.
doaj   +1 more source

The Brown Dwarf Kinematics Project (BDKP) I. Proper Motions and Tangential Velocities for a Large Sample of Late-type M, L and T Dwarfs

, 2008
We report proper motion measurements for 427 late-type M, L and T dwarfs, 332 of which have been measured for the first time. Combining these new proper motions with previously published measurements yields a sample of 841 M7-T8 dwarfs.
Ackerman, Adam J. Burgasser, Allen, Allen, Allers, Artigau, Bartlett, Berriman, Biller, Bochanski, Borysow, Bouy, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burgasser, Burrows, Burrows, Caballero, Chiba, Chiu, Christopher R. Gelino, Close, Costa, Costa, Covey, Covey, Cruz, Cruz, Cruz, Cushing, Dahn, Delfosse, Ellis, Epchtein, Fan, Frederick M. Walter, Geballe, Gilmore, Gizis, Gizis, Gizis, Gizis, Gizis, Gizis, Goldman, Golimowski, Hall, Hambly, Hawkins, Hawley, Henry, Henry, Irwin, Jacqueline K. Faherty, Jameson, Kelle L. Cruz, Kharchenko, Kirkpatrick, Kirkpatrick, Kirkpatrick, Kirkpatrick, Knapp, Leggett, Liebert, Liu, Liu, Looper, Looper, Luhman, Luhman, Luyten, Luyten, Luyten, Lépine, Lépine, Martín, McElwain, McGovern, McLean, Metchev, Metchev, Michael M. Shara, Mohanty, Mohanty, Mugrauer, Oort, Osorio, Perryman, Phan-Bao, Potter, Reid, Reid, Reid, Reid, Reid, Reid, Reid, Ruiz, Ruiz, Salim, Saumon, Schmidt, Schneider, Scholz, Schwarzschild, Siegler, Siegler, Skrutskie, Stern, Strauss, Teegarden, Teixeira, Tinney, Tinney, Tinney, Tinney, Tsvetanov, van Altena, Vrba, West, West, Wielen, Wilson, Wilson, Wilson, York, Zapatero Osorio   +141 more
core   +1 more source

Hawaii quasar and T dwarf survey. I. Method and discovery of faint field ultracool dwarfs [PDF]

, 2010
The Hawaii Quasar and T dwarf survey (HQT Survey) is a wide-field, red optical survey carried out with the Suprime-Cam mosaic CCD camera on the 8.2 m Subaru telescope. The HQT survey is designed to search for low-luminosity (M_(AB1450) 5.7) as well as
Capak, Peter L., Hu, Esther M., Kakazu, Yuko, Liu, Michael C., Wainscoat, Richard J., Wang, Wei-Hao   +5 more
core   +2 more sources

Disk or Companion: Characterizing Excess Infrared Flux in Seven White Dwarf Systems with Near-infrared Spectroscopy

The Astronomical Journal, 2023
Excess infrared flux from white dwarf stars is likely to arise from a dusty debris disk or a cool companion. In this work, we present near-infrared spectroscopic observations with Keck/MOSFIRE, Gemini/GNIRS, and Gemini/Flamingos-2 of seven white dwarfs ...
Dylan Owens, Siyi Xu, Elena Manjavacas, S. K. Leggett, S. L. Casewell, Erik Dennihy, Patrick Dufour, Beth L. Klein, Sherry Yeh, B. Zuckerman   +9 more
doaj   +1 more source

L Dwarf Variability:I‐Band Observations

The Astrophysical Journal, 2002
42 pages, 14 figures, minor corrections for typos and Figure 12, to appear in ApJ, v577, September 20 ...
Gelino, Christopher R., Marley, Mark S., Holtzman, Jon A., Ackerman, Andrew S., Lodders, Katharina   +4 more
openaire   +2 more sources

Strength through diversity: how cancers thrive when clones cooperate

Molecular Oncology, EarlyView.
Intratumor heterogeneity can offer direct benefits to the tumor through cooperation between different clones. In this review, Kuiken et al. discuss existing evidence for clonal cooperativity to identify overarching principles, and highlight how novel technological developments could address remaining open questions.
Marije C. Kuiken, Maartje Witsen, Emile E. Voest, Krijn K. Dijkstra   +3 more
wiley   +1 more source

A Sample of Very Young Field L Dwarfs and Implications for the Brown Dwarf "Lithium Test" at Early Ages

, 2008
Using a large sample of optical spectra of late-type dwarfs, we identify a subset of late-M through L field dwarfs that, because of the presence of low-gravity features in their spectra, are believed to be unusually young.
Adam J. Burgasser, Bannister N. P., Baraffe I., Borysow A., C. G. Tinney, Christopher R. Gelino, Dagny L. Looper, Delfosse X., Irwin M., J. Davy Kirkpatrick, James Liebert, John M. Carpenter, John R. Stauffer, Kelle L. Cruz, Lynne A. Hillenbrand, Mazzei P., Mermilliod J. C., Meynet G., Patrick J. Lowrance, Perryman M. A. C., Pozio F., Savage A., Steele I. A., Travis S. Barman, Ventura P.   +24 more
core   +1 more source

Parallaxes of L and T dwarfs [PDF]

Proceedings of the International Astronomical Union, 2004
We discuss a new program to measure the parallaxes of a number of L and T dwarfs, objects that bridge the gap between M dwarfs and planets. This pilot project tests the feasibility of using large telescopes with infrared detectors to determine parallaxes at the level of milli-arcseconds (mas). First results show that we are able to achieve the required
R. L. Smart, C. A. L. Bailer-Jones, H. R. A. Jones   +2 more
openaire   +1 more source