J/MNRAS/470/4838  Redshift catalog of HE 0435-1223 field-of-view (Sluse+, 2017)
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H0LiCOW. II. Spectroscopic survey and galaxy-group identification of the strong
gravitational lens system HE 0435-1223.
    Sluse D., Sonnenfeld A., Rumbaugh N., Rusu C.E., Fassnacht C.D., Treu T.,
    Suyu S.H., Wong K.C., Auger M.W., Bonvin V., Collett T., Courbin F.,
    Hilbert S., Koopmans L.V.E., Marshall P.J., Meylan G., Spiniello C.,
    Tewes M.
   <Mon. Not. R. Astron. Soc., 470, 4838-4857 (2017)>
   =2017MNRAS.470.4838S    (SIMBAD/NED BibCode)
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ADC_Keywords: Gravitational lensing ; QSOs ; Redshifts
Keywords: gravitational lensing: strong - galaxies: groups: general -
          quasars: individual: HE 0435-1223

Abstract:
    Galaxies located in the environment or along the line of sight towards
    gravitational lenses can significantly affect lensing observables, and
    can lead to systematic errors on the measurement of H_0_ from the
    time-delay technique. We present the results of a systematic
    spectroscopic identification of the galaxies in the field of view of
    the lensed quasar HE 0435-1223 using the W.M. Keck, Gemini and
    ESO-Very Large telescopes. Our new catalogue triples the number of
    known galaxy redshifts in the direct vicinity of the lens, expanding
    to 102 the number of measured redshifts for galaxies separated by less
    than 3 arcmin from the lens. We complement our catalogue with
    literature data to gather redshifts up to 15 arcmin from the lens, and
    search for galaxy groups or clusters projected towards HE 0435-1223.
    We confirm that the lens is a member of a small group that includes at
    least 12 galaxies, and find 8 other group candidates near the line of
    sight of the lens. The flexion shift, namely the shift of lensed
    images produced by high-order perturbation of the lens potential, is
    calculated for each galaxy/group and used to identify which objects
    produce the largest perturbation of the lens potential. This analysis
    demonstrates that (i) at most three of the five brightest galaxies
    projected within 12 arcsec of the lens need to be explicitly used in
    the lens models, and (ii) the groups can be treated in the lens model
    as an external tidal field (shear) contribution.

Description:
    Our data set combines multi-object spectroscopy obtained at
    Gemini-South, Keck, and ESO-Paranal observatories.

    The catalogue contains 534 unique objects, including 368 redshifts
    exclusively reported by MOM15 (Momcheva et al., 2015, Cat.
    J/ApJS/219/29). Our new measurement expands to 169 the number of
    targeted objects separated by less than 3 arcmin from the lens.

File Summary:
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 FileName      Lrecl  Records   Explanations
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ReadMe            80        .   This file
table1.dat        83      534   Spectroscopic redshift catalogue
table4.dat        74        9   Properties of the groups identified in the field
                                 of view of HE 0435-1223
tableb1.dat       74        7   Properties of the groups identified in the field
                                 of view of HE 0435-1223,
                                 but using Rvir to select the groups
tablec1.dat       23        9   Virial mass, associated uncertainty and radius
                                 of the groups identified in table4.dat
list.dat         141      174   List of fits spectra
fits/*             .      174   Individual fits spectra
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See also:
 J/MNRAS/467/4220 : Galaxies inside 120 arcsec of HE 0435-1223 (Rusu+, 2017)
 J/MNRAS/465/4914 : R-band light curves of HE 0435-1223 (Bonvin+, 2017)
 J/ApJS/219/29    : Spectroscopic redshifts in strong lens fields
                                                        (Momcheva+, 2015)

Byte-by-byte Description of file: table1.dat
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   Bytes Format Units   Label     Explanations
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   1- 24  A24   ---     Name      Name (1)
  26- 30  I5    ---     ID        Identification number
  32- 40  F9.6  deg     RAdeg     Right ascension (J2000)
  42- 51  F10.6 deg     DEdeg     Declination (J2000)
  53- 61  F9.6  ---     z         ?=99 Redshift
  63- 71  F9.6  ---   e_z         ?=99 Redshift error
      73  I1    ---   q_z         [0/6]? Redshift quality flag (2)
  75- 83  A9    ---     Type      Type (3)
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Note (1): Format: Instrument_date_objID, where instrument is FORS, Gemini or
  Keck if the redshift is derived from our survey, and Momcheva if the redshift
  comes from MOM15 (Momcheva et al., 2015, Cat. J/ApJS/219/29).
  The "date" in format yyyymmdd is the date of observation, or 201508 for
  objects from MOM15 (Momcheva et al., 2015, Cat. J/ApJS/219/29).
Note (2): Redshift quality flag as follows:
  0 = secure redshift, from this program
  1 = tentative redshift, from this program
  2 = unreliable/unknown redshift, from this program
  3 = data obtained with LDSS-3, for objects from MOM15
       (Momcheva et al., 2015, Cat. J/ApJS/219/29)
  4 = data obtained with IMACS, for objects from MOM15
       (Momcheva et al., 2015, Cat. J/ApJS/219/29)
  5 = data obtained with Hectospec, for objects from MOM15
       (Momcheva et al., 2015, Cat. J/ApJS/219/29)
  6 = NED objects, for objects from MOM15
       (Momcheva et al., 2015, Cat. J/ApJS/219/29)
Note (3): Type as follows:
  ETG-Sx    = CaK-H and/or G band are detected
  M-dwarf   = M-dwarf star
  Star      = other stellar-types
  Starburst = clear emission lines are observed
  Unknown   = no identification could be done or if the spectrum is from
               an external catalogue
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Byte-by-byte Description of file: table4.dat tableb1.dat
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   Bytes Format Units     Label    Explanations
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   1-  7  F7.5  ---       zgroup   Group mean redshift
       8  A1    ---     n_zgroup   [ab] Notes (1)
  10- 11  I2    ---       N        Number of spectroscopically identified
                                    galaxies in the group
  13- 16  I4    km/s      sigma    Group intrinsic velocity dispersion
                                    (rounded to 10km/s maximum precision)
  18- 20  I3    km/s    e_sigma    1{sigma} standard deviation of sigma
                                    from bootstrap
  22- 30  F9.6  deg       RAcent   Group centroid right ascension
  32- 41  F10.6 deg       DEcent   Group centroid declination
  43- 46  F4.2  arcmin  e_RAcent   Bootstrap error on the centroid RA
  48- 51  F4.2  arcmin  e_DEcent   Bootstrap error on the centroid DE
  53- 57  F5.1  arcsec    Dtheta   Projected distance of the centroid
                                    to the lens
  59- 63  F5.2 [arcsec]   logA3X   Median flexion shift log({DELTA}_3_x)
  65- 68  F4.2 [arcsec] e_logA3X   1{sigma} standard deviation on logA3X
                                    from bootstrapping (Section 5).
  70- 74  A5    arcmin    FOV      Indicates for which field of view the group
                                    is detected (the properties we display
                                    correspond to the field of view in first)
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Note (1): Notes as follows:
    a = Galaxy members drop to 8 if a radius of 15 arcmin is considered.
         The centroid location does not change but the velocity dispersion
         drops to sigma=233+/-63km/s.
    b = Possibly bimodal groups constituted of two (or more) subgroups.
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Byte-by-byte Description of file: tablec1.dat
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   Bytes Format Units    Label     Explanations
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   1-  6  F6.4  ---      <zgroup>  Group redshift
   8- 12  F5.2  [Msun]   logMvir   Virial mass
  14- 17  F4.2  [Msun] e_logMvir   rms uncertainty on logMvir
  19- 23  F5.3  Mpc      Rvir      Virial radius
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Byte-by-byte Description of file: list.dat
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   Bytes Format Units   Label     Explanations
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   1-  9  F9.6  deg     RAdeg     Right Ascension of center (J2000)
  11- 20  F10.6 deg     DEdeg     Declination of center (J2000)
  22- 25  I4    ---     Nx        Number of pixels along X-axis
  27- 49  A23  "datime" Obs.date  Observation date
  51- 57  F7.2  0.1nm   bWave     Lower value of wavelength interval
  59- 66  F8.2  0.1nm   BWave     Upper value of wavelength interval
  68- 74  F7.5  0.1nm   Wave      Wavelenght resolution
  76- 77  I2    Kibyte  size      Size of FITS file
  79-109  A31   ---     FileName  Name of FITS file, in subdirectory fits
 111-141  A31   ---     Title     Title of the FITS file
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History:
    From electronic version of the journal

References:
    Suyu et al.,      Paper  I     2017MNRAS.468.2590S
    Rusu et al.,      Paper III    2017MNRAS.467.4220R, Cat. J/MNRAS/467/4220
    Wong et al.,      Paper IV     2017MNRAS.465.4895W
    Bonvin et al.,    Paper V      2017MNRAS.465.4914B, Cat. J/MNRAS/465/4914
    Ding et al.,      Paper VI     2017MNRAS.465.4634D
    Ding et al.,      Paper VII    2017MNRAS.472...90D
    Tihhonova et al., Paper VIII   2018MNRAS.477.5657T
    Birrer et al.,    Paper IX     2019MNRAS.484.4726B
    Sluse et al.,     Paper X      2019MNRAS.490..613S

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(End)                                      Patricia Vannier [CDS]    24-Apr-2020
