2,755 research outputs found
Publishing an E-journal on a shoe string: Is it a sustainaible project?.
The aim of this article is to report on an experiment in publishing an open access journal and learn from it about the larger field of open access publishing. The experiment is the launch of the European Journal of Comparative Economics (EJCE), an on-line refereed and open access journal, founded in 2004 by the European Association for Comparative Economic Studies and LIUC University in Italy. They embarked upon this project in part to respond to the rising concentration in the market for scientific publishing and the resulting use of market power to raise subscription prices and restrict access to scientific output. We had hoped that open access journals could provide some countervailing power and increase competition in the field. Our experience running a poorly endowed journal has shown that entry to the field may be easy, yet that making it a sustainable enterprise is not straightforward.Open-access publishing, online journals, scientific publication
Probing Individual Star Forming Regions Within Strongly Lensed Galaxies at z > 1
Star formation occurs on physical scales corresponding to individual star
forming regions, typically of order ~100 parsecs in size, but current
observational facilities cannot resolve these scales within field galaxies
beyond the local universe. However, the magnification from strong gravitational
lensing allows us to measure the properties of these discrete star forming
regions within galaxies in the distant universe. New results from
multi-wavelength spectroscopic studies of a sample of extremely bright, highly
magnified lensed galaxies are revealing the complexity of star formation on
sub-galaxy scales during the era of peak star formation in the universe. We
find a wide range of properties in the rest-frame UV spectra of individual
galaxies, as well as in spectra that originate from different star forming
regions within the same galaxy. Large variations in the strengths and velocity
structure of Lyman-alpha and strong P Cygni lines such as C IV, and MgII
provide new insights into the astrophysical relationships between extremely
massive stars, the elemental abundances and physical properties of the nebular
gas those stars ionize, and the galactic-scale outflows they power.Comment: 4 pages, 3 figures. To be published in the Proceedings of IAU
Symposium 309. For more details and closely related work see also
arXiv:1310.6695 and arXiv:1406.335
Stellar Populations of Highly Magnified Lensed Galaxies: Young Starbursts at z~2
We present a comprehensive analysis of the rest-frame UV to near-IR spectral
energy distributions and rest-frame optical spectra of four of the brightest
gravitationally lensed galaxies in the literature: RCSGA 032727-132609 at
z=1.70, MS1512-cB58 at z=2.73, SGAS J152745.1+065219 at z=2.76 and SGAS
J122651.3+215220 at z=2.92. This includes new Spitzer imaging for RCSGA0327 as
well as new spectra, near-IR imaging and Spitzer imaging for SGAS1527 and
SGAS1226. Lensing magnifications of 3-4 magnitudes allow a detailed study of
the stellar populations and physical conditions. We compare star formation
rates as measured from the SED fit, the H-alpha and [OII] emission lines, and
the UV+IR bolometric luminosity where 24 micron photometry is available. The
SFR estimate from the SED fit is consistently higher than the other indicators,
which suggests that the Calzetti dust extinction law used in the SED fitting is
too flat for young star-forming galaxies at z~2. Our analysis finds similar
stellar population parameters for all four lensed galaxies: stellar masses
3-7*10^9 M_sun, young ages ~ 100 Myr, little dust content E(B-V)=0.10-0.25, and
star formation rates around 20-100 M_sun/yr. Compared to typical values for the
galaxy population at z~2, this suggests we are looking at newly formed,
starbursting systems that have only recently started the build-up of stellar
mass. These results constitute the first detailed, uniform analysis of a sample
of the growing number of strongly lensed galaxies known at z~2.Comment: 13 pages, 8 figures, Accepted to Ap
Searching for Cooling Signatures in Strong Lensing Galaxy Clusters: Evidence Against Baryons Shaping the Matter Distribution in Cluster Cores
The process by which the mass density profile of certain galaxy clusters
becomes centrally concentrated enough to produce high strong lensing (SL)
cross-sections is not well understood. It has been suggested that the baryonic
condensation of the intra-cluster medium (ICM) due to cooling may drag dark
matter to the cores and thus steepen the profile. In this work, we search for
evidence of ongoing ICM cooling in the first large, well-defined sample of
strong lensing selected galaxy clusters in the range 0.1 < z < 0.6. Based on
known correlations between the ICM cooling rate and both optical emission line
luminosity and star formation, we measure, for a sample of 89 strong lensing
clusters, the fraction of clusters that have [OII]3727 emission in their
brightest cluster galaxy (BCG). We find that the fraction of line-emitting BCGs
is constant as a function of redshift for z > 0.2 and shows no statistically
significant deviation from the total cluster population. Specific star
formation rates, as traced by the strength of the 4000 angstrom break, D_4000,
are also consistent with the general cluster population. Finally, we use
optical imaging of the SL clusters to measure the angular separation, R_arc,
between the arc and the center of mass of each lensing cluster in our sample
and test for evidence of changing [OII] emission and D_4000 as a function of
R_arc, a proxy observable for SL cross-sections. D_4000 is constant with all
values of R_arc, and the [OII] emission fractions show no dependence on R_arc
for R_arc > 10" and only very marginal evidence of increased weak [OII]
emission for systems with R_arc < 10". These results argue against the ability
of baryonic cooling associated with cool core activity in the cores of galaxy
clusters to strongly modify the underlying dark matter potential, leading to an
increase in strong lensing cross-sections.Comment: 9 Pages, 5 Figures, 1 Tabl
Spatially Resolved Galactic Wind in Lensed Galaxy RCSGA 032727-132609
We probe the spatial distribution of outflowing gas along four lines of sight
separated by up to 6 kpc in a gravitationally-lensed star-forming galaxy at
z=1.70. Using MgII and FeII emission and absorption as tracers, we find that
the clumps of star formation are driving galactic outflows with velocities of
-170 to -250 km/sec. The velocities of MgII emission are redshifted with
respect to the systemic velocities of the galaxy, consistent with being
back-scattered. By contrast, the FeII fluorescent emission lines are either
slightly blueshifted or at the systemic velocity of the galaxy. Taken together,
the velocity structure of the MgII and FeII emission is consistent with arising
through scattering in galactic winds. Assuming a thin shell geometry for the
out owing gas, the estimated masses carried out by these outfows are large (>
30 - 50 ), with mass loading factors several times the
star-formation rate. Almost 20% to 50% of the blueshifted absorption probably
escapes the gravitational potential of the galaxy. In this galaxy, the outflow
is "locally sourced", that is, the properties of the outflow in each line of
sight are dominated by the properties of the nearest clump of star formation;
the wind is not global to the galaxy. The mass outflow rates and the momentum
flux carried out by outflows in individual star forming knots of this object
are comparable to that of starburst galaxies in the local Universe.Comment: 19 pages, 10 figure, accepted for publication in MNRA
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Equality Opportunity: Marriage Litigation and Iowaâs Equal Protection Law
Discrimination claims against longstanding rules invite the public and the courts to rethink the status quo and address overarching legal and social commitments to equality together with questions specific to the case at hand. Lawsuits seeking marriage rights for same-sex couples quintessentially illustrate this multilayered nature of law reform litigation, as the debates they provoke focus not only on the rights of same-sex couples but also on the meaning of marriage and the meaning of equality more generally. While few other than lawyers, judges, and perhaps some reporters actually read the equal protection and due process arguments that the presiding court will consider, many community members where marriage litigation is taking place become fully engaged in debating the equality and fundamental rights questions implicated by the legal claims.
This degree of popular attention certainly exists in Iowa, where talk of gay couples marrying took center stage even before a lawsuit was filed in the Iowa district court in 2005. The suit, which was brought by six lesbian and gay couples and eventually joined by some of the couplesâ children, is one of many marriage equality suits to be filed in recent years and is the first to be filed in the Midwest.
Yet while the public debate may be wide-ranging, it typically misses the ways in which the lawsuit may have long-term consequences for a stateâs equality jurisprudence that extend well beyond marriage. In Iowa, specifically, while Varnum v. Brien focuses directly on marriage equality, the case also engages an ongoing conversation among the stateâs courts about how Iowaâs equality guarantees should be enforced.
This essay introduces an amicus brief filed with the Iowa Supreme Court on behalf of three Iowa constitutional law scholars that addresses
these broad questions about the future of Iowa equal protection law. In publishing the brief with the University of Iowa College of Lawâs Journal of Gender, Race & Justice, we aim to show why, both in Iowa and around the country, courts would be better off embracing a single standard of equal protection review rather than the ossified and often ineffective federal tiered approach. By highlighting the briefâs implications for issues beyond marriage, we also aim to illustrate the point that law reform litigation, especially regarding contested social issues, often implicates not only the specific claim before the court but also other far-reaching questions about the jurisprudential status quo
Common Loons Respond Adaptively to a Black Fly that Reduces Nesting Success
Nesting birds must often cope with harassment from biting insects, but it is difficult to ascertain what effect such pests might have on breeding success and population dynamics. We tested the hypothesis that a black fly (Simulium annulus) that feeds on the blood of nesting Common Loons (Gavia immer) causes nest abandonment in this charismatic diving bird. In addition, we measured effects of fly-induced abandonment on a loon population, and examined potential predictors of fly abundance and nest abandonment. We also tested a second hypothesis, which holds that loon pairs that abandon a nest owing to flies should often remain at the site for their subsequent nesting attempt, since fly outbreaks last only 1â2 weeks. All predictions of the fly-induced abandonment hypothesis were supported, including strong correlations between fly counts and rate of abandonment, reduced incubation during severe fly years, and increased abandonment during cool springs, which promote longevity of the flies. The correlation between nest abandonment and population breeding success suggests that S. annulus reduced the chick fledging rate by as much as 23% in a year of severe infestation. Fly numbers on loons and their nests were highest when temperatures were high and winds were light. Surprisingly, however, exposure to the prevailing wind increased, not decreased, nest abandonment, perhaps because of wave action. Lake size was inversely and female age directly correlated with abandonment rate, possibly due to food limitation in small lakes and senescence of females, respectively. Finally, pairs that abandoned a first nest renested at the same site with much greater frequency than did pairs that lost eggs to a predator, indicating that loons are capable of responding adaptively to a cause of nest failure that is time- but not space-dependent
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