Inici     Començant     Sobreviure a l'Univers    
Inhabited Sky
    News@Sky     Astro Fotografia     La Col·lecció     Fòrum     Blog New!     FAQ     Premsa     Login  

TYC 1375-641-1


Contingut

Imatges

Carregar la teva Imatge

DSS Images   Other Images


Articles Relacionats

The Spectra of T Dwarfs. II. Red Optical Data
We present 6300-10100 Å spectra for a sample of 13 T dwarfsobserved using LRIS mountedtpdel 99 on the Keck I 10 m Telescope. Avariety of features are identified and analyzed, includingpressure-broadened K I and Na I doublets; narrow Cs I and Rb I lines;weak CaH, CrH, and FeH bands; strong H2O absorption; and apossible weak CH4 band. Hα emission is detected inthree of the T dwarfs, strong in the previously reported active T dwarf2MASS 1237+6526 and weak in SDSS 1254-0122 and 2MASS 1047+2124. None ofthe T dwarfs exhibit Li I absorption. Guided by the evolution of opticalspectral features with near-infrared spectral type, we derive a paralleloptical classification scheme, focusing on spectral types T5 to T8,anchored to select spectral standards. We find general agreement betweenoptical and near-infrared types for nearly all the T dwarfs so farobserved, including two earlier type T dwarfs, within our classificationuncertainties (~1 subtype). These results suggest that competing gravityand temperature effects compensate for each other over the 0.6-2.5 μmspectral region. We identify one possible means of disentangling theseeffects by comparing the strength of the K I red wing to the 9250Å H2O band. One of our objects, 2MASS 0937+2931,exhibits a peculiar spectrum with a substantial red slope and relativelystrong FeH absorption, both consequences of a metal-deficientatmosphere. On the basis of its near-infrared properties and substantialspace motion, this object may be a thick disk or halo brown dwarf.

Enviar un nou article


Enllaços Relacionats

  • - No s'ha trobat enllaços -
Enviar un nou enllaç


Membre dels grups següents:


Dades d'Observació i Astrometria

Constel·lació:Gemini
Ascensió Recta:07h57m17.55s
Declinació:+21°42'32.9"
Magnitud Aparent:9.273
Moviment propi RA:-18.4
Moviment propi Dec:-54.5
B-T magnitude:9.968
V-T magnitude:9.331

Catàlegs i designacions:
Noms Propis   (Edit)
TYCHO-2 2000TYC 1375-641-1
USNO-A2.0USNO-A2 1050-05494154
HIPHIP 38871

→ Sol·licitar més catàlegs i designacions de VizieR