Data Set Overview
  =================
    Observations of 11 Iannini asteroid family members were obtained
    between November 2004 and March 2007 with the goal of obtaining a
    representative sample of Iannini family members over the visual
    wavelength region.  Observations were made using the 10 m Keck II
    telescope, located on Mauna Kea, Hawaii.  The ESI spectrograph (Sheinis et
    al. 2002) [SHENISETAL2002], equipped with a Lincoln Labs 2K x 4K CCD, was
    used in low dispersion mode with a prism to cover a wavelength range of
    approximately 0.39 to 1.0 microns. The resolution of ESI with a 6 arc
    second slit increases with wavelength from approximately 1150 at 0.39
    microns to 2900 at 1.0 microns.  Effects resulting from the asteroid's
    rotational lightcurve can be neglected when imaging the entire spectral
    range simultaneously.
 
    While the typical seeing at Keck gives images with a FWHM of less than or
    equal to 0.8 arcsec, a 1.0 arcsec wide slit was used through 2005, was
    increased to 1.25 arcsec for 2006, and finally increased to 6.0 arcsec for
    all subsequent nights. The slit width was increased because it allowed
    easier centering and alignment of the target onto the slit, and resulted
    in greater consistency amongst reduced spectra. The slit was aligned with
    the parallactic angle at the midpoint of each observation. Observations
    were conducted at the rate of motion of the targets and at airmass below
    1.3.
 
    A total of 11 asteroids were successfully observed.  The data have
    been published in Willman, et al. (2008Icar...195...663W)
    [WILLMANETAL2008].
 
    The spectra show a familial similarity and are believed to be
    representative of young S class surfaces aged by space weathering over a
    few million years, the dynamically estimated collisional age of the
    family.
 
    During the data reduction process, spectra of solar analogs were divided
    into the raw asteroid spectra to produce values of relative reflectance.
    The standard procedure was to combine all analogs from the night into a
    master analog. This single hybrid analog was then used to calibrate each
    asteroid spectrum. The following is a list of the analogs that were used
    for each of the nights:
    2004-11-10: BS448, BS582, BS660, BS720, BS2643, BS8041, BS9107
    2006-01-04: BS4030, Hya64, SA98-978, SA102-1081
    2006-01-05: BS4030, BS9107, Hya64, SA98-978
    2007-03-10: SA98-978, SA102-1081, SA107-684
    2006-10-01: SA110-361, SA113-276, SA93-101

Confidence Level Overview
  =========================
    The user is referred to the paper in which these data were published:
    Willman, et al. (2008Icar...195...663W) [WILLMANETAL2008] for information
    about the confidence level of the data.
 
    The time intervals for each object in Table 1 of Willman, et al.
    (2008Icar...195...663W) [WILLMANETAL2008] correspond to the midpoints of
    the first and last observations. The START_TIME and STOP_TIME for the data
    presented here correspond to the start of the first exposure and the end
    of the last exposure respectively.
 
    The date of observation for asteroids (81550) 2000 HU23 and (150781)  2001
    QO282 is incorrectly listed as 2007 March 09 in Table 1 of Willman, et al.
    (2008Icar...195...663W) [WILLMANETAL2008]. The correct date should read
    2007 March 10. This correction has been made for the data presented here.