Access to Astronomical Catalogues

J/ApJ/731/4          Galactic halo as seen by the CFHTLS          (Sesar+, 2011)
The shape and profile of the Milky Way halo as seen by the Canada-France-Hawaii
Telescope Legacy Survey.
    Sesar B., Juric M., Ivezic Z.
   <Astrophys. J., 731, 4 (2011)>
   =2011ApJ...731....4S
ADC_Keywords: Photometry, SDSS ; Stars, halo ; Surveys

Keywords: Galaxy: halo - Galaxy: stellar content - Galaxy: structure -
          stars: statistics

Abstract:
    We use Canada-France-Hawaii Telescope Legacy Survey data for
    170deg2, recalibrated and transformed to the Sloan Digital Sky
    Survey ugri photometric system, to study the distribution of
    near-turnoff main-sequence stars in the Galactic halo along four lines
    of sight to heliocentric distances of ∼35kpc. We find that the halo
    stellar number density profile becomes steeper at Galactocentric
    distances greater than Rgal∼28kpc, with the power-law index changing
    from ninner=-2.62±0.04 to nouter=-3.8±0.1. In particular, we
    test a series of single power-law models and find them to be strongly
    disfavored by the data. The parameters for the best-fit Einasto
    profile are n=2.2±0.2 and Re=22.2±0.4kpc. We measure the
    oblateness of the halo to be q=c/a=0.70±0.01 and detect no evidence
    of it changing across the range of probed distances. The Sagittarius
    stream is detected in the l=173° and b=-62° direction as an
    overdensity of [Fe/H]~-1.5dex stars at Rgal∼32kpc, providing a new
    constraint for the Sagittarius stream and dark matter halo models. We
    also detect the Monoceros stream as an overdensity of [Fe/H]>-1.5dex
    stars in the l=232° and b=26° direction at Rgal≲25kpc. In
    the two sight lines where we do not detect significant substructure,
    the median metallicity is found to be independent of distance within
    systematic uncertainties ([Fe/H]~-1.5±0.1dex).

Description:
    The astrometry in these catalogs is accurate to within 0.2" relative
    to external reference frames (Gwyn 2008PASP..120..212G). The catalogs
    are available for each pointing (a pointing is ∼1deg2 part of a
    CFHTLS field) through the Canadian Astronomy Data Centre (CADC) Web
    site.

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table3.dat        34      171   Δtotalj,f values for the CFHTLS fields


See also:
   II/317 : The CFHTLS Survey (T0007 release) (Hudelot+ 2012)
   J/A+A/509/A81 : Candidate clusters detected in six CFHTLS fields (Adami+,
                   2010)
   J/A+A/494/845 : Galaxy clusters in the CFHTLS (Grove+, 2009)
   J/ApJ/633/630 : Low-mass stars found in CFHTLS (Willott+, 2005)
   http://www1.cadc-ccda.hia-iha.nrc-cnrc.gc.ca/community/CFHTLS-SG/docs/
        cfhtlswide.html : CFHTLS Wide Field stacked images and catalogues


Byte-by-byte Description of file: table3.dat

   Bytes Format Units   Label     Explanations

   1-  6  A6    ---     Point     Pointing identification (1)
       7  A1    ---     f_i'      [*] i'_2_ band used (2)
   9- 13  F5.3  mag     u*        The u* band Δ^total^_j,f_ value (3)
  15- 20  F6.3  mag     g'        The g' band Δ^total^_j,f_ value (3)
  22- 27  F6.3  mag     r'        The r' band Δ^total^_j,f_ value (3)
  29- 34  F6.3  mag     i'        The i' band Δ^total^_j,f_ value (3)

Note (1): Where the first two bytes give the CFHTLS field as given in table 1:
   ------------------------------------------------------------------------
   CFHTLS Field  RA (J2000)  DEC (deg)  GLON (deg) GLAT (deg)  Sky Coverage
   ------------------------------------------------------------------------
     W1           34.5       -7.0       173.12     -61.59      72
     W2          134.5       -3.3       231.78      26.04      25
     W3          214.4       54.5        98.70      58.47      49
     W4          333.3        1.3        63.32     -41.84      25
   ------------------------------------------------------------------------
Note (2):
    * = used the i'2 band instead of i' (The i'2 filter is the new CFHT
        filter that was installed after the i' filter broke in 2007 October).
Note (3): Where Δtotj,f is the total correction for the jth
          pointing in the f field. See section 2.3.3.


History:
    From electronic version of the journal
(End)                 Greg Schwarz [AAS], Emmanuelle Perret [CDS]    12-Oct-2012