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J/ApJS/141/469     Linear polarization catalog toward HD 62542  (Pereyra+, 2002)
Polarimetry toward the IRAS Vela shell. I. The catalog.
    Pereyra A., Magalhaes A.M.
   <Astrophys. J. Suppl. Ser. 141, 469 (2002)>
   =2002ApJS..141..469P
ADC_Keywords: Polarization ; Magnetic fields ; Interstellar medium

Keywords: catalogs - ISM: clouds - ISM: individual (Gum Nebula, Vela Shell) -
          ISM: magnetic fields - polarization - stars: individual (HD 62542)

Abstract:
    We have obtained linear polarization measurements of stars along the
    western side of the IRAS Vela Shell toward HD 62542. From 16 CCD
    fields distributed along the ionization front (I-front) we have built
    a catalog of 856 objects with polarization signal-to-noise ratio
    larger than 10. We detect very significant levels of polarization and
    hence an appreciable magnetic field throughout the region. Composite
    polarization maps around the I-front are shown. In some regions the
    polarization vectors are parallel to the I-front, but a perpendicular
    trend is also evident along parts of the front. In addition, the
    polarization pattern seems to be affected by gas streaming inside the
    cloud.

    The observations were made using a CCD imaging polarimeter attached to
    the 1.5m Telescope of Cerro Tololo Inter-American Observatory (CTIO),
    Chile. The data were collected in 1991 December and 1992 December.

Table 1: CCD Field Positions
--------------------------------------------------
 Field    RA    (J2000)  DE         Obs. Date
--------------------------------------------------
  01    7 42 37.08   -42 13 44.66   Dec. 1991
  02    7 42 01.22   -42 07 02.30   Dec. 1991
  03    7 41 25.31   -42 02 02.93   Dec. 1991
  04    7 43 12.93   -42 20 25.03   Dec. 1991
  05    7 38 59.84   -41 36 55.29   Dec. 1992
  06    7 39 32.15   -41 28 59.42   Dec. 1992
  07    7 40 03.96   -41 36 59.53   Dec. 1992
  08    7 40 03.70   -41 44 59.52   Dec. 1992
  09    7 40 35.51   -41 53 01.63   Dec. 1992
  10    7 42 11.43   -42 01 06.96   Dec. 1992
  11    7 42 10.92   -42 17 07.95   Dec. 1992
  12    7 42 42.72   -42 25 11.05   Dec. 1992
  13    7 42 10.66   -42 25 07.94   Dec. 1992
  14    7 41 06.41   -42 29 03.71   Dec. 1992
  15    7 40 09.39   -42 56 59.98   Dec. 1992
  16    7 39 36.94   -43 08 58.84   Dec. 1992

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table2.dat        75      875   Field data


Byte-by-byte Description of file: table2.dat

   Bytes Format Units   Label     Explanations

   1-  5  A5    ---     ---       [Field]
   7- 12  A6    ---     [PM2002]  Name (FF NNN) (1)
  14- 18  A5    ---     ---       [Field]
  20- 25  A6    ---    [PM2002]2  Second designation in an other field
  27- 28  I2    h       RAh       Hour of Right Ascension (J2000)
  30- 31  I2    min     RAm       Minute of Right Ascension (J2000)
  33- 37  F5.2  s       RAs       Second of Right Ascension (J2000)
      39  A1    ---     DE-       Sign of the Declination (J2000)
  40- 41  I2    deg     DEd       Degree of Declination (J2000)
  43- 44  I2    arcmin  DEm       Arcminute of Declination (J2000)
  46- 50  F5.2  arcsec  DEs       Arcsecond of Declination (J2000)
  52- 56  F5.3  %       PolV      Percent linear polarization in the V band
  58- 62  F5.3  %       e_PolV    Measured error in PolV (2)
  64- 68  F5.1  deg     PA        Polarization angle (3)
  70- 74  F5.2  mag     Vmag      The V band magnitude

Note (1): Designation:
     [PM2002] FF NNN, where
      FF is the number of the field and
     NNN the number of the object in the field
Note (2): The latter are obtained from the residuals of the observations
    at each waveplate position angle (ψi) with respect to the
    expected cos4ψi curve; they are consistent with the photon noise
    errors (Magalhaes, Benedetti & Roland, 1984PASP...96..383M).
Note (3): Measured from North to East.



History:
    From electronic version of the journal
(End)                    Greg Schwarz [AAS], Patricia Bauer [CDS]    17-Sep-2002