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J/A+A/598/A92        New ultracool subdwarfs                     (Lodieu+, 2017)

New ultracool subdwarfs identified in large-scale surveys using VO tools. II. SDSS DR7 vs. UKIDSS LAS DR6, SDSS DR7 vs. UKIDSS LAS DR8, SDSS DR9 vs. UKIDSS LAS DR10, and SDSS DR7 vs. 2MASS. Lodieu N., Espinoza Contreras M., Zapatero Osorio M.R., Solano E., Aberasturi M., Martin E.L. <Astron. Astrophys. 598, A92 (2017)> =2017A&A...598A..92L (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Stars, late-type ; Photometry, SDSS ; Photometry, infrared ; Proper motions ; Spectroscopy Keywords: Galaxy: halo - subdwarfs - techniques: photometric - techniques: spectroscopic - virtual observatory tools Abstract: We developed an efficient method to search for late-type subdwarfs. We carried out a search cross-matching SDSS, 2MASS, and UKIDSS with VO tools. We considered different photometric and proper motion criteria for our selection. We identified 100 late-type subdwarf candidates. We obtained our own low-resolution optical spectra for 71 of our candidates and retrieved Sloan spectra for 30 of them (9 in common to the 71). We classified 92 candidates based on optical spectra. Our new discoveries include 49 subdwarfs, 25 extreme subdwarfs, six ultrasubdwarfs, one subdwarf/extreme subdwarf, and two dwarfs/subdwarfs. In addition, we discovered three early-L subdwarfs. We double the numbers of cool subdwarfs and derived a surface density of late-type subdwarfs. Description: Optical spectra of 92 late-type dwarfs from GTC/OSIRIS, VLT/FORS2, NOT/ALFOSC, and SDSS. Each file contains wavelength (in Angstroms) and the flux (in ergs/cm2/sec/Angstrom) in the first and second column, respectively. Fluxes are normalised at 1.0 at 7500 Angstroms. Names of files are composed of ID number followed by HHMMsDDMM of the coordinates of the object (where 's' is the sign) Tables 1, 2, and 4 of the paper are available through CDS. The data presented in this paper and CDS are also gathered in a VO-compliant archive at http://svo2.cab.inta-csic.es/vocats/ltsa/ and include even more options for visualisation. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 157 100 ID, coordinates, photometry, and proper motions table2.dat 82 87 ID, proper motion, and reduced proper motions table4.dat 114 101 ID,TiO5,CaH1,CaH2,CaH3,SpT,d,Vh,U,V,W sp/* 44 101 Individual spectra
See also: J/A+A/493/L27 : Parallaxes of 10 ultracool subdwarfs (Schilbach+, 2009) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 3 I03 --- ID ID number 5- 6 I2 h RAh Right ascension (J2000.0) 8- 9 I2 min RAm Right ascension (J2000.0) 11- 15 F5.2 s RAs Right ascension (J2000.0) 17 A1 --- DE- Declination sign (J2000.0) 18- 19 I2 deg DEd Declination (J2000.0) 21- 22 I2 arcmin DEm Declination (J2000.0) 24- 27 F4.1 arcsec DEs Declination (J2000.0) 29- 34 F6.3 mag umag SDSS u magnitude 36- 40 F5.3 mag e_umag Error on the SDSS u magnitude 42- 47 F6.3 mag gmag SDSS g magnitude 49- 53 F5.3 mag e_gmag Error on the SDSS g magnitude 55- 60 F6.3 mag rmag SDSS r magnitude 62- 66 F5.3 mag e_rmag Error on the SDSS r magnitude 68- 73 F6.3 mag imag SDSS i magnitude 75- 79 F5.3 mag e_imag Error on the SDSS i magnitude 81- 86 F6.3 mag zmag SDSS z magnitude 88- 92 F5.3 mag e_zmag Error on the SDSS z magnitude 94- 99 F6.3 mag Ymag ?=99.999 UKIDSS Y magnitude 101-105 F5.3 mag e_Ymag ?=9.999 Error on the UKIDSS Y magnitude 107-112 F6.3 mag Jmag 2MASS or UKIDSS J magnitude 114-118 F5.3 mag e_Jmag Error on the 2MASS or UKIDSS J magnitude 120-125 F6.3 mag Hmag ?=99.999 2MASS or UKIDSS H magnitude 127-131 F5.3 mag e_Hmag ?=9.999 Error on the 2MASS or UKIDSS H magnitude 133-138 F6.3 mag Kmag 2MASS or UKIDSS K magnitude 140-144 F5.3 mag e_Kmag Error on the 2MASS or UKIDSS K magnitude 146-150 F5.3 arcsec/yr pm Total proper motion 152-157 F6.3 mag Hr Reduced proper motion
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 3 I03 --- ID ID number 5- 9 F5.3 arcsec/yr pmVO Proper motion from the VO 11- 16 F6.3 mag HrVO Reduced proper motion from the VO 18- 23 F6.3 arcsec/yr pmRA Proper motion in RA from images 25- 29 F5.3 arcsec/yr e_pmRA Error on proper motion in RA from images 31- 37 F7.4 arcsec/yr pmDE Proper motion in dec from images 39- 43 F5.3 arcsec/yr e_pmDE Error on proper motion in DE from images 45- 49 F5.3 arcsec/yr pm Revised total proper motion 51- 55 F5.3 arcsec/yr e_pm Error on revised total proper motion 57- 62 F6.3 deg Hr Revised reduced proper motion 64- 68 F5.3 deg e_Hr Error on revised Hr 70- 75 F6.3 deg b_Hr Minimum value of Hr 77- 82 F6.3 deg B_Hr Maximum value on Hr
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 3 I03 --- ID ID number 5- 9 F5.3 --- TiO5 TiO5 index 11- 15 F5.3 --- CaH1 CaH1 index 17- 21 F5.3 --- CaH2 CaH2 index 23- 27 F5.3 --- CaH3 CaH3 index 29- 36 A8 --- SpTypeL Spectral type based on Lepine's scheme 38- 51 A14 --- SpType Adopted spectral type 53- 56 A4 --- Tel Telescope 58- 62 F5.1 pc Dist ?=999.9 Distance 64- 68 F5.1 pc e_Dist ?=99.9 Error on the distance 70- 73 I4 km/s HV ?=999 Heliocentric velocity 75- 77 I3 km/s e_HV ?=99 Error on the heliocentric velocity 79- 84 F6.1 km/s Uvel ?=999.9 Space motion: U component 86- 89 F4.1 km/s e_Uvel ?=99.9 Space motion: error on U component 91- 96 F6.1 km/s Vvel ?=999.9 Space motion: V component 98-102 F5.1 km/s e_Vvel ?=99.9 Space motion: error on V component 104-109 F6.1 km/s Wvel ?=999.9 Space motion: W component 111-114 F4.1 km/s e_Wvel ?=99.9 Space motion: error on W component
Byte-by-byte Description of file: sp/*
Bytes Format Units Label Explanations
1- 19 F19.13 0.1nm Lambda Wavelength (in Angstroms) 21- 44 E24.18 10mW/m2/nm Flux Flux (in ergs/cm2/s/Å)
Acknowledgements: Nicolas Lodieu, nlodieu(at)iac.es References: Lodieu et al., Paper I 2012A&A...542A.105L
(End) Nicolas Lodieu [IAC, Tenerife, Spain], Patricia Vannier [CDS] 17-Oct-2016
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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