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J/ApJ/671/2040      Polarisation of candidates Be stars      (Wisniewski+, 2007)

The role of evolutionary age and metallicity in the formation of classical Be circumstellar disks. II. Assessing the evolutionary nature of candidate disk systems. Wisniewski J.P., Bjorkman K.S., Magalhaes A.M., Bjorkman J.E., Meade M.R., Pereyra A. <Astrophys. J., 671, 2040-2058 (2007)> =2007ApJ...671.2040W
ADC_Keywords: Magellanic Clouds ; Stars, Be ; Polarization Keywords: circumstellar matter - galaxies: clusters: individual (Bruck 60, NGC 330, NGC 346, NGC 371, NGC 456, NGC 458, LH 72, NGC 1818, NGC 1858, NGC 1948, NGC 2004, NGC 2100) - Magellanic Clouds - stars: emission-line, Be - techniques: polarimetric - stars: individual (pi Aquarii, BD +61 154, MWC 349A) Abstract: We present the first detailed imaging polarization observations of six SMC and six LMC clusters, known to have large populations of B-type stars that exhibit excess Hα emission from 2-CD photometric studies, to constrain the evolutionary status of these stars and hence better establish links between the onset of disk formation in classical Be stars and cluster age and/or metallicity. We parameterize and remove the interstellar polarization (ISP) associated with each line of sight, thereby isolating the presence of any intrinsic polarization. We use the wavelength dependence of this intrinsic polarization to discriminate pure gas disk systems, i.e., classical Be stars, from composite gas-plus-dust disk systems, i.e., Herbig Ae/Be or B[e] stars. Description: The imaging polarimetry data presented in this study were obtained with the Cerro Tololo Inter-American Observatory (CTIO)7 1.5m telescope. between 2001 Oct 17 and 2001 Nov 27. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 00 51 41.7 -73 13 47 Bruck 60 = DEM S 60 05 32 12. -66 27 LH 72 = LH 72 00 56 18.7 -72 27 50 NGC 330 = Cl Kron 35 00 59 18. -72 10 48 NGC 346 = Cl Kron 39 01 03 25. -72 04 24 NGC 371 = Cl Kron 48 01 13 50. -73 18 00 NGC 456 = Cl Kron 65 01 14 53.4 -71 32 59 NGC 458 = Cl Kron 69 05 04 13.8 -66 26 02 NGC 1818 = KMHK 491 05 09 56.1 -68 54 06 NGC 1858 = LH 31 05 24 20.0 -66 24 12 NGC 1948 = DEM L 175a 05 30 40.2 -67 17 14 NGC 2004 = KMHK 991 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table6.dat 53 1792 Total polarization of candidate Be stars table7.dat 53 1792 Intrinsic polarization of candidate Be stars table8.dat 67 369 Classifying the intrinsic polarization of individual candidate Be stars table13.dat 56 120 IR colors of candidate Be stars
See also: J/A+AS/119/271 : Be stars uvbyβ photometry (Fabregat+, 1996) J/A+AS/125/75 : UBV photometry of Be stars (Pavlovski+ 1997) J/A+AS/129/289 : Long-term spectrophotometry of Be stars (Moujtahid+ 1998) J/A+AS/134/489 : Be stars in MC young clusters (Keller+ 1999) J/A+A/317/448 : BVRHalpha photometry of NGC 1818 (Grebel 1997) J/A+A/376/144 : BV(RI)CHα photometry of NGC 663 (Pigulski+, 2001) J/other/NewA/9.509 : IRAS observations of Be stars (Zhang+, 2004) J/other/NewA/10.325 : 2MASS observations of Be stars (Zhang+, 2005) J/MNRAS/361/1055 : BVI photometry of LMC Be stars (Sabogal+, 2005) J/ApJ/622/1052 : byHα photometry of NGC 3766 (McSwain+, 2005) J/A+A/462/683 : Velocities in SMC field of NGC 330 (Martayan+, 2007) J/A+A/472/577 : NGC 330 Be stars and binaries (Martayan+, 2007) J/A+A/478/659 : OGLE Be stars in Galactic Bulge (Sabogal+, 2008) J/ApJ/652/458 : Candidates Be stars BVRHa photometry (Wisniewski+, 2006) Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 19 A19 --- ID Candidate Be star identification 21 A1 --- Filt [ubvri] Filter used in the observation 23- 27 F5.2 % Polt ? Total polarization (1) 29- 34 F6.2 deg polPAt ? Position angle of total polarization 36- 41 F6.3 % Qt ? Stokes Q polarization 43- 47 F5.2 % Ut ? Stokes U polarization 49- 53 F5.2 % e_Polt ? Polarization error
Note (1): Interstellar plus intrinsic components.
Byte-by-byte Description of file: table7.dat
Bytes Format Units Label Explanations
1- 19 A19 --- ID Candidate Be star identification 21 A1 --- Filt [ubvri] Filter used in the observation 23- 27 F5.2 % Poli ? Intrinsic polarization 29- 34 F6.2 deg polPAi ? Position angle of intrinsic polarization 35- 40 F6.2 % Qi ? Stokes Q polarization 42- 46 F5.2 % Ui ? Stokes U polarization 49- 53 F5.2 % e_Poli ? Polarization error
Byte-by-byte Description of file: table8.dat
Bytes Format Units Label Explanations
1- 19 A19 --- ID Candidate Be star identification 21- 22 A2 --- Jump Polarization Balmer jump present? 24- 27 A4 --- PAdes Polarization position angle description (1) 29- 31 F3.1 --- Class Be star classification (2) 33- 67 A35 --- Comm Additional comments
Note (1): Position angle was flat (F), linearly sloped (S), or randomly variable (V) while the numbers indicate the σ level of such characterizations. Note (2): The likelihood each object is a bona-fide classical Be star based on the 4 point classification scheme described in the text.
Byte-by-byte Description of file: table13.dat
Bytes Format Units Label Explanations
1- 19 A19 --- ID Candidate Be star identification (1) 21- 34 A14 --- Class Polarimetric designation (2) 36- 40 F5.2 mag J-H 2MASS (J-H) color index 42- 46 F5.2 mag H-K 2MASS (H-K) color index 48- 51 F4.2 mag e_J-H Error in J-H (3) 53- 56 F4.2 mag e_H-K Error in H-K (3)
Note (1): Near-IR colors are tabulated for all candidate Be stars in clusters investigated in this paper which were detected in all three 2MASS photometric bands. Note (2): Polarimetric designation as follows: Type-1:Bal-J = Type-1 sources which we assert are most likely to be classical Be stars Type-2:ES = Type-2 sources which exhibit electron scattering intrinsic polarimetric signatures and are thus likely classical Be stars Type-2-4,other = All other sources, regardless of whether they were detected via our polarimetric survey or not Note (3): Obtained by adding individual filter errors in quadrature.
History: From electronic version of the journal References: Wisniewski & Bjorkman, Paper II, 2006ApJ...652..458W (Cat. J/ApJ/652/458)
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 10-Nov-2009
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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