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The Porcupine Survey: A Distributed Survey and WISE Followup
Spitzer post-cryogen observations to perform a moderate depth survey distributed around the sky are proposed. Field centers are chosen to be WISE brown dwarf candidates, which will typically be 160 µJy at 4.7 µm and randomly distributed around the sky. The Spitzer observations will give much higher sensitivity, higher angular resolution, and a time baseline to measure both proper motions and possibly parallaxes. The distance and velocity data obtained on the WISE brown dwarf candidates will greatly improve our knowledge of the mass and age distribution of brown dwarfs. The outer parts of the Spitzer fields surrounding the WISE positions will provide a deep survey in many narrow fields of view distributed around the sky, and the volume of this survey will contain many more distant brown dwarfs, and many extragalactic objects
Multiple case-study analysis of quality management practices within UK Six Sigma and non-Six Sigma manufacturing small- and medium-sized enterprises
This paper examines multiple case-study analysis of quality management practices within UK Six Sigma and non-Six Sigma manufacturing small- and medium-sized enterprises
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So you call that research? : mending methodological biases in strategy and organization departments of top business schools
We believe that all strategy and organization (SO) scholars should be able to decide for themselves whether to specialize in certain parts of the knowledge cycle or adopt a broader, multi-method view on the scientific process. In a situation of ―methodological pluralism‖, individuals might choose to contribute to the construction of new administrative theories by means of qualitative works like case studies, ethnographies, biographies, or grounded theory studies (e.g., see Denzin and Lincoln, 2000). Others could then specialize in testing these theories by means of experiments, surveys, or longitudinal econometric studies (e.g., see Lewis-Beck, 1987-2004). Again others could combine both approaches in Herculean attempts to conduct high-impact, integrative research with the potential to change the way we understand the field as a whole
Resist, comply or workaround? An examination of different facets of user engagement with information systems
This paper provides a summary of studies of user resistance to Information Technology (IT) and identifies workaround activity as an understudied and distinct, but related, phenomenon. Previous categorizations of resistance have largely failed to address the relationships between the motivations for divergences from procedure and the associated workaround activity. This paper develops a composite model of resistance/workaround derived from two case study sites. We find four key antecedent conditions derived from both positive and negative resistance rationales and identify associations and links to various resultant workaround behaviours and provide supporting Chains of Evidence from two case studies
The First Ultra-cool Brown Dwarf Discovered by the Wide-field Infrared Survey Explorer
We report the discovery of the first new ultra-cool brown dwarf (BDs) found with the Wide-field Infrared Survey
Explorer (WISE). The object’s preliminary designation is WISEPC J045853.90+643451.9. Follow-up spectroscopy
with the LUCIFER instrument on the Large Binocular Telescope indicates that it is a very late-type T dwarf with a
spectral type approximately equal to T9. Fits to an IRTF/SpeX 0.8–2.5 μm spectrum to the model atmospheres of
Marley and Saumon indicate an effective temperature of approximately 600 K as well as the presence of vertical
mixing in its atmosphere. The new BD is easily detected by WISE, with a signal-to-noise ratio of ~36 at 4.6 μm.
Current estimates place it at a distance of 6–10 pc. This object represents the first in what will likely be hundreds of
nearby BDs found by WISE that will be suitable for follow-up observations, including those with the James Webb
Space Telescope. One of the two primary scientific goals of the WISE mission is to find the coolest, closest stars to
our Sun; the discovery of this new BD proves that WISE is capable of fulfilling this objective
Deep mid-infrared observations of Lyman-break galaxies
As part of the In-Orbit Checkout activities for the Spitzer Space Telescope,
the IRAC team carried out a deep observation (average integration time ~8
hours) of a field surrounding the bright QSO HS 1700+6416. This field contains
several hundred z~3 Lyman-break galaxy candidates, and we report here on their
mid-infrared properties, including the IRAC detection rate, flux densities and
colors, and the results of fitting population synthesis models to the optical,
near-infrared, and IRAC magnitudes. The results of the model-fitting show that
previous optical/near-infrared studies of LBGs were not missing large, hidden
old stellar populations. The LBG candidates' properties are consistent with
those of massive, star-forming galaxies at z~3. Other IRAC sources in the same
field have similar properties, so IRAC selection may prove a promising method
of finding additional high-redshift galaxies.Comment: ApJS in press (Spitzer special issue); 13 pages, 3 figure
HST Morphologies of z~2 Dust Obscured Galaxies I: Power-law Sources
We present high spatial resolution optical and near-infrared imaging obtained
using the ACS, WFPC2 and NICMOS cameras aboard the Hubble Space Telescope of 31
24um--bright z~2 Dust Obscured Galaxies (DOGs) identified in the Bootes Field
of the NOAO Deep Wide-Field Survey. Although this subset of DOGs have mid-IR
spectral energy distributions dominated by a power-law component suggestive of
an AGN, all but one of the galaxies are spatially extended and not dominated by
an unresolved component at rest-frame UV or optical wavelengths. The observed
V-H and I-H colors of the extended components are 0.2-3 magnitudes redder than
normal star-forming galaxies. All but 1 have axial ratios >0.3, making it
unlikely that DOGs are composed of an edge-on star-forming disk. We model the
spatially extended component of the surface brightness distributions of the
DOGs with a Sersic profile and find effective radii of 1-6 kpc. This sample of
DOGs is smaller than most sub-millimeter galaxies (SMGs), but larger than
quiescent high-redshift galaxies. Non-parametric measures (Gini and M20) of DOG
morphologies suggest that these galaxies are more dynamically relaxed than
local ULIRGs. We estimate lower limits to the stellar masses of DOGs based on
the rest-frame optical photometry and find that these range from ~10^(9-11)
M_sun. If major mergers are the progenitors of DOGs, then these observations
suggest that DOGs may represent a post-merger evolutionary stage.Comment: 23 pages, 9 figures, 6 tables, accepted to ApJ; lower limits on
stellar mass revised upwards by factor of (1+z
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