845 research outputs found
The A2667 Giant Arc at z=1.03: Evidence for Large-scale Shocks at High Redshift
We present the spatially resolved emission line ratio properties of a ~10^10
M_sun star-forming galaxy at redshift z=1.03. This galaxy is gravitationally
lensed as a triple-image giant arc behind the massive lensing cluster Abell
2667. The main image of the galaxy has magnification factors of 14+/-2.1 in
flux and ~ 2 by 7 in area, yielding an intrinsic spatial resolution of 115-405
pc after AO correction with OSIRIS at KECK II. The HST morphology shows a
clumpy structure and the H\alpha\ kinematics indicates a large velocity
dispersion with V_{max} sin(i)/\sigma ~ 0.73, consistent with high redshift
disk galaxies of similar masses. From the [NII]/H\alpha\ line ratios, we find
that the central 350 parsec of the galaxy is dominated by star formation. The
[NII]/H\alpha\ line ratios are higher in the outer-disk than in the central
regions. Most noticeably, we find a blue-shifted region of strong
[NII]/H\alpha\ emission in the outer disk. Applying our recent HII region and
slow-shock models, we propose that this elevated [NII]/H\alpha\ ratio region is
contaminated by a significant fraction of shock excitation due to galactic
outflows. Our analysis suggests that shocked regions may mimic flat or inverted
metallicity gradients at high redshift.Comment: 11 pages, 9 figures, ApJ accepte
EC55-102 Fall-Sown Small Grain Varieties for Nebraska, 1955
Extension Circular 55-102: This contains information about different small grain varieties for fall planting
CC116 Suggestions for Handling Summer Fallowed Land which will not be Planted to Winter Wheat
Extension Circular CC116 This circular contains suggestions for handling summer fallowed land which will not be planted to winter wheat
CC180 Revised 1961 Castorbean Production in Nebraska
Campaign Circulation 180R is about Castorbean production in Nebraska 1961
CC180 Revised 1961 Castorbean Production in Nebraska
Campaign Circulation 180R is about Castorbean production in Nebraska 1961
Producing Sugar Beets : Extension Circular 1-61-2
Manual for producing sugar beets from start to finish
Producing Sugar Beets : Extension Circular 1-61-2
Manual for producing sugar beets from start to finish
EC58-123 Questions and Answers about Stubble Mulching
Extension Circular 58-123 provides questions and answers about Stubble Mulch farming
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