76 T dwarfs from the UKIDSS LAS: benchmarks, kinematics and an updated space density

被引：92

作者：

Burningham, Ben ^{[1
,2
]}

Cardoso, C. V. ^{[1
,3
]}

Smith, L. ^{[1
]}

Leggett, S. K. ^{[4
]}

Smart, R. L. ^{[3
]}

Mann, A. W. ^{[5
]}

Dhital, S. ^{[6
]}

Lucas, P. W. ^{[1
]}

Tinney, C. G. ^{[7
,8
]}

Pinfield, D. J. ^{[1
]}

Zhang, Z. ^{[1
]}

Morley, C. ^{[9
]}

Saumon, D. ^{[10
]}

Aller, K. ^{[5
]}

Littlefair, S. P. ^{[11
]}

Homeier, D. ^{[12
,13
]}

Lodieu, N. ^{[14
,15
]}

Deacon, N. ^{[16
]}

Marley, M. S. ^{[17
]}

van Spaandonk, L. ^{[1
]}

Baker, D. ^{[1
]}

Allard, F.

Andrei, A. H. ^{[2
,3
,18
,19
]}

Canty, J. ^{[1
]}

Clarke, J. ^{[1
]}

Day-Jones, A. C. ^{[1
,20
]}

Dupuy, T. ^{[21
]}

Fortney, J. J. ^{[9
]}

Gomes, J. ^{[1
]}

Ishii, M. ^{[22
]}

Jones, H. R. A. ^{[1
]}

Liu, M. ^{[5
]}

Magazzu, A. ^{[23
]}

Marocco, F. ^{[1
]}

Murray, D. N.

Rojas-Ayala, B. ^{[24
]}

Tamura, M. ^{[25
]}

机构：

[1] Univ Hertfordshire, Sci & Technol Res Inst, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England

[2] Observ Nacl, BR-20921400 Rio De Janeiro, Brazil

[3] Osserv Astron Torino, Ist Nazl Astrofis, I-10025 Pino Torinese, Italy

[4] Gemini Observ, Hilo, HI 96720 USA

[5] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA

[6] Boston Univ, Dept Astron, Boston, MA 02215 USA

[7] Univ New S Wales, Australian Ctr Astrobiol, Sydney, NSW 2052, Australia

[8] Univ New S Wales, Sch Phys, Sydney, NSW 2052, Australia

[9] Univ Calif Santa Cruz, Dept Astron & Astrophys, Santa Cruz, CA 95064 USA

[10] Los Alamos Natl Lab, Los Alamos, NM 87545 USA

[11] Univ Sheffield, Dept Phys & Astron, Sheffield S3 7RH, S Yorkshire, England

[12] Univ Gottingen, Inst Astrophys, D-37077 Gottingen, Germany

[13] Ecole Normale Super Lyon, CRAL, CNRS, UMR 5574, F-69364 Lyon, France

[14] Inst Astrofis Canarias, E-38200 San Cristobal la Laguna, Spain

[15] Inst Astrofis Canarias, E-38200 San Cristobal la Laguna, Spain

[16] Max Planck Inst Astron, D-69117 Heidelberg, Germany

[17] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA

[18] Shanghai Astron Observatory, CAS, Shanghai 200030, Peoples R China

[19] Univ Fed Rio de Janeiro, Observat Valongo, BR-20080090 Rio de Janeiro, Brazil

[20] Univ Chile, Camino Observ, Santiago, Chile

[21] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA

[22] Subaru Telescope, Hilo, HI 96720 USA

[23] INAF, Fundac Galileo Galilei, E-38700 Santa Cruz De La Palma, Spain

[24] Amer Museum Nat Hist, Dept Astrophys, New York, NY 10024 USA

[25] Natl Astron Observ, Mitaka, Tokyo 1818588, Japan

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2013年 / 433卷 / 01期

基金：

美国国家科学基金会;

关键词：

surveys; brown dwarfs; stars: low-mass; INITIAL MASS FUNCTION; DIGITAL SKY SURVEY; GALACTIC CLUSTERS SURVEY; INFRARED-SURVEY-EXPLORER; INTEGRAL-FIELD SPECTROGRAPH; COOLEST BROWN DWARFS; EARLY DATA RELEASE; LARGE-AREA SURVEY; SOLAR NEIGHBORHOOD; L/T TRANSITION;

D O I：

10.1093/mnras/stt740

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report the discovery of 76 new T dwarfs from the UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS). Near-infrared broad- and narrow-band photometry and spectroscopy are presented for the new objects, along with Wide-field Infrared Survey Explorer (WISE) and warm-Spitzer photometry. Proper motions for 128 UKIDSS T dwarfs are presented from a new two epoch LAS proper motion catalogue. We use these motions to identify two new benchmark systems: LHS 6176AB, a T8p+M4 pair and HD 118865AB, a T5.5+F8 pair. Using age constraints from the primaries and evolutionary models to constrain the radii, we have estimated their physical properties from their bolometric luminosity. We compare the colours and properties of known benchmark T dwarfs to the latest model atmospheres and draw two principal conclusions. First, it appears that the H - [4.5] and J - W2 colours are more sensitive to metallicity than has previously been recognized, such that differences in metallicity may dominate over differences in T-eff when considering relative properties of cool objects using these colours. Secondly, the previously noted apparent dominance of young objects in the late-T dwarf sample is no longer apparent when using the new model grids and the expanded sample of late-T dwarfs and benchmarks. This is supported by the apparently similar distribution of late-T dwarfs and earlier type T dwarfs on reduced proper motion diagrams that we present. Finally, we present updated space densities for the late-T dwarfs, and compare our values to simulation predictions and those from WISE.

引用

页码：457 / 497

页数：41

共 124 条

[11] Evolutionary models for cool brown dwarfs and extrasolar giant planets. The case of HD 209458 [J].

Baraffe, I ;

Chabrier, G ;

Barman, TS ;

Allard, F ;

Hauschildt, PH .

ASTRONOMY & ASTROPHYSICS, 2003, 402 (02) :701-712

[12]

Barrado, 2002, ASTRON ASTROPHYS, V395, P813

[13] A Universal Stellar Initial Mass Function? A Critical Look at Variations [J].

Bastian, Nate ;

Covey, Kevin R. ;

Meyer, Michael R. .

ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS, VOL 48, 2010, 48 :339-389

[14] THE COLDEST BROWN DWARF (OR FREE-FLOATING PLANET)?: THE Y DWARF WISE 1828+2650 [J].

Beichman, C. ;

Gelino, Christopher R. ;

Kirkpatrick, J. Davy ;

Barman, Travis S. ;

Marsh, Kenneth A. ;

Cushing, Michael C. ;

Wright, E. L. .

ASTROPHYSICAL JOURNAL, 2013, 764 (01)

[15] SExtractor: Software for source extraction [J].

Bertin, E ;

Arnouts, S .

ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES, 1996, 117 (02) :393-404

[16] Low-mass dwarf template spectra from the Sloan Digital Sky Survey [J].

Bochanski, John J. ;

West, Andrew A. ;

Hawley, Suzanne L. ;

Covey, Kevin R. .

ASTRONOMICAL JOURNAL, 2007, 133 (02) :531-544

[17] FIRE SPECTROSCOPY OF THE ULTRA-COOL BROWN DWARF, UGPS J072227.51-054031.2: KINEMATICS, ROTATION AND ATMOSPHERIC PARAMETERS [J].

Bochanski, John J. ;

Burgasser, Adam J. ;

Simcoe, Robert A. ;

West, Andrew A. .

ASTRONOMICAL JOURNAL, 2011, 142 (05)

[18] THE LUMINOSITY AND MASS FUNCTIONS OF LOW-MASS STARS IN THE GALACTIC DISK. II. THE FIELD [J].

Bochanski, John J. ;

Hawley, Suzanne L. ;

Covey, Kevin R. ;

West, Andrew A. ;

Reid, I. Neill ;

Golimowski, David A. ;

Ivezic, Zeljko .

ASTRONOMICAL JOURNAL, 2010, 139 (06) :2679-2699

[19] MASE: A New Data-Reduction Pipeline for the Magellan Echellette Spectrograph [J].

Bochanski, John J. ;

Hennawi, Joseph F. ;

Simcoe, Robert A. ;

Prochaska, J. Xavier ;

West, Andrew A. ;

Burgasser, Adam J. ;

Burles, Scott M. ;

Bernstein, Rebecca A. ;

Williams, Christopher L. ;

Murphy, Michael T. .

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 2009, 121 (886) :1409-1418

[20] Astrometric and photometric initial mass functions from the UKIDSS Galactic Clusters Survey - III. Praesepe [J].

Boudreault, S. ;

Lodieu, N. ;

Deacon, N. R. ;

Hambly, N. C. .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2012, 426 (04) :3419-3434

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