J/MNRAS/361/211 JHK photometry of brown dwarfs in Orion (Lucas+, 2005) ================================================================================ A deep survey of brown dwarfs in Orion with Gemini. Lucas P.W., Roche P.F., Tamura M. =2005MNRAS.361..211L ================================================================================ ADC_Keywords: Surveys ; Clusters, open ; Stars, pre-main sequence ; Stars, dwarfs ; Photometry, infrared Keywords: surveys - circumstellar matter - stars: formation - stars: low-mass, brown dwarfs Abstract: We report the results of a deep near-infrared (JHK) survey of the outer parts of the Trapezium Cluster with Gemini South/Flamingos. 396 sources were detected in a 26-arcmin^2^ area, including 138 brown dwarf candidates, defined as M<0.075M_{sun}_ for an assumed age of 1Myr. Only 33 of the brown dwarf candidates are planetary mass candidates with estimated masses in the range 0.003150AU) binary companions. Description: Near-infrared imaging in the J (1.25um), H (1.65um) and K (2.2um) bands was carried out at two epochs with the Flamingos I camera on the Gemini South telescope at Cerro Pachon, Chile. All observations were made in queue mode by observatory staff. The first data set was taken on the nights of 2001 October 7, 10, 12, 15-17. One field was observed, the camera pixel scale of 0.076arcsec yielding a field of view of 156arcsec. The second data set, comprising two Flamingos fields, was taken in 2002 with a science grade array of the same type on the nights of October 29-31, and November 1, 2, 4 and 12. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table2.dat 67 395 Source catalogue -------------------------------------------------------------------------------- See also: J/A+A/429/1007 : RIJHK phot. of VLM objects near eps Ori (Scholz+, 2005) J/AJ/127/2856 : Brown dwarfs in the 2MASS Survey (Burgasser+, 2004) J/MNRAS/356/89 : sigma Ori low-mass stars (Kenyon+, 2005) J/AN/325/705 : RIJHKs of low-mass stars in sigma Ori (Bejar+, 2004) Byte-by-byte Description of file: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 --- [LRT2005] Sequential number 5- 12 A8 --- Name Coordinate based ID (SSs-MSS or MSSs-MSS)) 13 A1 --- n_Name [e] Note on Name (1) 15- 16 I2 h RAh Right ascension (J2000.0) (2) 18- 19 I2 min RAm Right ascension (J2000.0) 21- 26 F6.3 s RAs Right ascension (J2000.0) 28 A1 --- DE- Declination sign (J2000.0) 29- 30 I2 deg DEd Declination (J2000.0) 32- 33 I2 arcmin DEm Declination (J2000.0) 35- 39 F5.2 arcsec DEs Declination (J2000.0) 41- 45 F5.2 mag Kmag K (2.2um) magnitude (3) 47- 51 F5.2 mag Hmag H (1.65um) magnitude (3) 53- 57 F5.2 mag Jmag J (1.25um) magnitude (3) 59- 61 A3 --- Flag [JHK] Flag about flux incertainty (4) 63 I1 --- r_Kmag Reference for K flux (5) 65 I1 --- r_Hmag Reference for H flux (5) 67 I1 --- r_Jmag Reference for J flux (5) -------------------------------------------------------------------------------- Note (1): 395 sources are listed but Source 265 is a binary listed as a single source because both components were saturated and barely resolved. Note (2): Estimated precision in the world coordinate system is 0.5 arcseconds. Note (3): Sources not detected in a passband have the dummy values: 0.000 = undetected sources -1.000 = sources off the edge of the data mosaic -2.000 = saturated sources not seen in other surveys -3.000 = binaries unresolved in some passbands Note (4): Highly uncertain fluxes (>0.2 mag) are indicated by letters in this column denoting the passband(s) with uncertain flux. Note (5): Sources in general have fluxes drawn from one or more datasets, indicated separately for the K, H and J fluxes in that order. The source is indicated by the following key: 0 = this survey 1 = Lucas et al., 2001MNRAS.326..695L 2 = the 2MASS All Sky Survey, Cat. 3 = the 2MASS 2nd Incremental Data Release (Cat. II/241) 4 = Hillenbrand & Carpenter, 2000, Cat. 5 = Muench et al., 2002, Cat. -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Patricia Vannier [CDS] 10-Apr-2006