49 research outputs found
Short Cuts
A bit of Iowa clay (not any clay, but one that has just the right something in it) and a bit of lard tossed into the vats of sorghum sirup mills on Iowa farms have modified an old process in the making of sorghum that is resulting in clear golden sirup which is fully the equal of the product of the best commercial factories
LBT/ARGOS adaptive optics observations of z lensed galaxies
Gravitationally lensed systems allow a detailed view of galaxies at high
redshift. High spatial- and spectral-resolution measurements of arc-like
structures can offer unique constraints on the physical and dynamical
properties of high-z systems. We present near-infrared spectra centred on the
gravitational arcs of six known z ~ 2 lensed star-forming galaxies of stellar
masses of 10^9-10^11 Msun and star formation rate (SFR) in the range between 10
and 400 Msun/yr. Ground layer adaptive optics (AO)-assisted observations are
obtained at the Large Binocular Telescope (LBT) with the LUCI spectrographs
during the commissioning of the ARGOS facility. We used MOS masks with curved
slits to follow the extended arched structures and study the diagnostic
emission lines. Combining spatially resolved kinematic properties across the
arc-like morphologies, emission line diagnostics and archival information, we
distinguish between merging and rotationally supported systems, and reveal the
possible presence of ejected gas. For galaxies that have evidence for outflows,
we derive outflow energetics and mass-loading factors compatible with those
observed for stellar winds in local and high-z galaxies. We also use flux ratio
diagnostics to derive gas-phase metallicities. The low signal-to-noise ratio in
the faint H and nitrogen lines allows us to derive an upper limit of ~
0.15 dex for the spatial variations in metallicity along the slit for the
lensed galaxy J1038. Analysed near-infrared spectra presented here represent
the first scientific demonstration of performing AO-assisted multi-object
spectroscopy with narrow curved-shape slits. The increased angular and spectral
resolution, combined with the binocular operation mode with the 8.4-m-wide eyes
of LBT, will allow the characterisation of kinematic and chemical properties of
a large sample of galaxies at high-z in the near future.Comment: 18 pages, 13 figures, accepted for publication in A&
ANDES, the high resolution spectrograph for the ELT: project management and system engineering approaches for mastering its preliminary design phase
ANDES, the high resolution spectrograph for the ELT: science case, baseline design and path to construction
4MOST: Project overview and information for the First Call for Proposals
We introduce the 4-metre Multi-Object Spectroscopic Telescope (4MOST), a new high-multiplex, wide-field spectroscopic survey facility under development for the four-metre-class Visible and Infrared Survey Telescope for Astronomy (VISTA) at Paranal. Its key specifications are: a large field of view (FoV) of 4.2 square degrees and a high multiplex capability, with 1624 fibres feeding two low-resolution spectrographs (), and 812 fibres transferring light to the high-resolution spectrograph (). After a description of the instrument and its expected performance, a short overview is given of its operational scheme and planned 4MOST Consortium science; these aspects are covered in more detail in other articles in this edition of The Messenger. Finally, the processes, schedules, and policies concerning the selection of ESO Community Surveys are presented, commencing with a singular opportunity to submit Letters of Intent for Public Surveys during the first five years of 4MOST operations
The Returns to Physical Capital in Knowledge Production: Evidence from Lab Disasters
We establish the importance of physical capital in knowledge production. To this end, we exploit adverse events (explosions, fires, floods, etc.) at research institutions as exogenous physical capital shocks. Scientists experience a substantial and persistent reduction in research output if they lose specialized physical capital, that is, equipment and material they created over time for a particular research purpose. In contrast, they quickly recover if they only lose generic physical capital. Affected scientists in older laboratories, which presumably lose more obsolete physical capital, are more likely to change their direction of research and recover in scientific productivity. These findings suggest that a scientist's investments into their own physical capital yield lasting returns but also create path dependence in relation to research direction