109 research outputs found
Some Like it Hot, Some Like it Cold, Most Like it Here: Forecasting Retirement in the Chicago Region
Over the next 20 years, an explosion of senior citizens who will opt to retire in the region rather than move away will change the face of the Chicago metropolitan region dramatically. This study, forecasting retirement trends in the 6-county Chicago metropolitan region through the year 2020, projects an overall 40 percent increase in the regions population of seniors who are age 60 or older. The increase outpaces the regions expected 16 percent growth in overall population over the next 20 years.The number of seniors not living in designated senior housing will increase by 18 percent in the City of Chicago, 22 percent in suburban Cook County, and by 58 percent in the collar counties. An additional 28,000 seniors are expected to be in the market for designated senior housing by 2020 and this demand is likely to outpace current supply.The study found the regions seniors who are retired or considering retirement are most concerned with (by ranking of importance):-- Availability of quality medical care-- Cost of living-- Availability of assistance and social services-- Public transportation-- Affordable housing-- Opportunities for culture and recreations-- Availability of high-quality housing with full services program
Magnetizing Neighborhoods Through Amateur Arts Performance
Outlines the Arts and Cultural Indicators in Community Building Project's findings on how amateur, informal arts activity improves a community's desirability, social integration, and quality of life as measured by population, test scores, and crime rates
Income Diversity and the Context of Community Development
The report "Income Diversity and the Context of Community Development" presents the MCIC Income Diversity Index: a three-decade retrospective analysis that seeks to establish a framework to describe patterns of neighborhood economic change in the City of Chicago. This analysis of household income data from the U.S. Census (1970-2000) shows that, while some wealthy Chicago neighborhoods have gotten richer and some poor neighborhoods have gotten poorer, many Chicago neighborhoods are remarkably stable.After researching and developing an innovative, new measure of income diversity, MCIC has identified four distinct patterns of neighborhood economic change in the City of Chicago, since 1970:1) Emerging high net worth2) Emerging low net worth3) Emerging bipolarity4) Stable diversityMCIC identified patterns for each of the 77 Chicago Community Areas to provide an important context for community development strategies.For example, in an Emerging High Income neighborhood (21 in all), the high-income population is increasing and the low-income population is decreasing. Development strategies in these areas should focus on protecting low- to moderate- income households from radical displacement and encourage the use of upgraded public and commercial services.An Emerging Low Income neighborhood, on the other hand, tracks a decline in the high-income population and an increase in the low-income population. In these communities, development efforts should focus on developing infrastructure, investing in buildings and retaining moderate- to high-income households.Additionally, the MCIC study identifies a disturbing "Desertification" trend among half of Chicago's 22 Emerging Low Income communities. In these neighborhoods, disinvestment and neglect have driven away middle- and high- income households.The City's 15 "Bipolar" neighborhoods have seen increases in both high- and low-income residents, and the remaining 19 communities maintain stable, economically diverse populations.Based on household income data from the U.S. Census, the MCIC analysis does not track change in income diversity since the year 2000. However, it does illustrate income trends that provide useful context and baseline data for community development strategists
More than a Pastime: Informal Arts Improve Communities and Increase Participation Formal Arts Participation
Street festivals, art fairs, and a wide variety of other cultural activities that take place in libraries, church basements and city parks may be found in just about every Chicago neighborhood. These are called "informal" arts activities to differentiate them from more formally established public and private cultural organizations and institutions, like The Art Institute of Chicago, the Chicago Architecture Foundation or the Chicago Theater, that are also key components of Chicago's vibrant cultural community. Because many more people participate in informal arts activities than "formal" ones, they are an important indicator of neighborhood quality of life and patterns of economic development in the City of Chicago. MCIC recently partnered with The Urban Institute in Washington DC to evaluate local datasets and measure community participation in arts and cultural activities in the City of Chicago. The research goal was to integrate arts and culture-related measures into neighborhood quality of life indicator models
Spectroscopic Identification of Massive Galaxies at z~2.3 with Strongly Suppressed Star Formation
We present first results of a spectroscopic survey targeting K-selected
galaxies at z=2.0-2.7 using the GNIRS instrument on Gemini-South. We obtained
near-infrared spectra with a wavelength coverage of 1.0-2.5 micron for 26
K-bright galaxies (K<19.7) selected from the MUSYC survey using photometric
redshifts. We successfully derived spectroscopic redshifts for all 26 galaxies
using rest-frame optical emission lines or the redshifted Balmer/4000 Angstrom
break. Twenty galaxies have spectroscopic redshifts in the range 2.0<z<2.7, for
which bright emission lines like Halpha and [OIII] fall in atmospheric windows.
Surprisingly, we detected no emission lines for nine of these 20 galaxies. The
median 2 sigma upper limit on the rest-frame equivalent width of Halpha for
these nine galaxies is ~10 Angstrom. The stellar continuum emission of these
same nine galaxies is best fitted by evolved stellar population models. The
best-fit star formation rate (SFR) is zero for five out of nine galaxies, and
consistent with zero within 1 sigma for the remaining four. Thus, both the
Halpha measurements and the independent stellar continuum modeling imply that
45% of our K-selected galaxies are not forming stars intensely. This high
fraction of galaxies without detected line emission and low SFRs may imply that
the suppression of star formation in massive galaxies occurs at higher redshift
than is predicted by current CDM galaxy formation models. However, obscured
star formation may have been missed, and deep mid-infrared imaging is needed to
clarify this situation.Comment: Accepted for publication in ApJ Letter
The Origin of Line Emission in Massive z~2.3 Galaxies: Evidence for Cosmic Downsizing of AGN Host Galaxies
Using the Gemini Near-InfraRed Spectrograph (GNIRS), we have assembled a
complete sample of 20 K-selected galaxies at 2.0<z<2.7 with high quality
near-infrared spectra. As described in a previous paper, 9 of these 20 galaxies
have strongly suppressed star formation and no detected emission lines. The
present paper concerns the 11 galaxies with detected Halpha emission, and
studies the origin of the line emission using the GNIRS spectra and follow-up
observations with SINFONI on the VLT. Based on their [NII]/Halpha ratios, the
spatial extent of the line emission and several other diagnostics, we infer
that four of the eleven emission-line galaxies host narrow line active galactic
nuclei (AGNs). The AGN host galaxies have stellar populations ranging from
evolved to star-forming. Combining our sample with a UV-selected galaxy sample
at the same redshift that spans a broader range in stellar mass, we find that
black-hole accretion is more effective at the high-mass end of the galaxy
distribution (~2.9x10^11 Msun) at z~2.3. Furthermore, by comparing our results
with SDSS data, we show that the AGN activity in massive galaxies has decreased
significantly between z~2.3 and z~0. AGNs with similar normalized accretion
rates as those detected in our K-selected galaxies reside in less massive
galaxies (~4.0x10^10 Msun) at low redshift. This is direct evidence for
downsizing of AGN host galaxies. Finally, we speculate that the typical stellar
mass-scale of the actively accreting AGN host galaxies, both at low and at high
redshift, might be similar to the mass-scale at which star-forming galaxies
seem to transform into red, passive systems.Comment: Accepted for publication in the Astrophysical Journa
The stellar mass structure of massive galaxies from z=0 to z=2.5; surface density profiles and half-mass radii
We present stellar mass surface density profiles of a mass-selected sample of
177 galaxies at 0.5 < z < 2.5, obtained using very deep HST optical and
near-infrared data over the GOODS-South field, including recent CANDELS data.
Accurate stellar mass surface density profiles have been measured for the first
time for a complete sample of high-redshift galaxies more massive than 10^10.7
M_sun. The key advantage of this study compared to previous work is that the
surface brightness profiles are deconvolved for PSF smoothing, allowing
accurate measurements of the structure of the galaxies. The surface brightness
profiles account for contributions from complex galaxy structures such as rings
and faint outer disks. Mass profiles are derived using radial rest-frame u-g
color profiles and a well-established empirical relation between these colors
and the stellar mass-to-light ratio. We derive stellar half-mass radii from the
mass profiles, and find that these are on average ~25% smaller than rest-frame
g band half-light radii. This average size difference of 25% is the same at all
redshifts, and does not correlate with stellar mass, specific star formation
rate, effective surface density, Sersic index, or galaxy size. Although on
average the difference between half-mass size and half-light size is modest,
for approximately 10% of massive galaxies this difference is more than a factor
two. These extreme galaxies are mostly extended, disk-like systems with large
central bulges. These results are robust, but could be impacted if the central
dust extinction becomes high. ALMA observations can be used to explore this
possibility. These results provide added support for galaxy growth scenarios
wherein massive galaxies at these epochs grow by accretion onto their outer
regions.Comment: 11 pages, 8 figures, 3 tables, accepted for publication in Ap
The Star Formation Rate-Density Relation at 0.6<z<0.9 and the Role of Star Forming Galaxies
We study the star formation rates (SFRs) of galaxies as a function of local
galaxy density at 0.6<z<0.9. We used a low-dispersion prism in IMACS on the
6.5-m Baade (Magellan I) telescope to obtain spectra and measured redshifts to
a precision of sigma_z/(1+z)=1% for galaxies with z<23.3 AB mag. We utilized a
stellar mass-limited sample of 977 galaxies above M>1.8x10^{10} Msun to conduct
our main analysis. With three different SFR indicators, (1) Spitzer MIPS
24-micron imaging, (2) SED fitting, and (3) [OII]3727 emission, we find the
median specific SFR (SSFR) and SFR to decline from the low-density field to the
cores of groups and a rich cluster. For the SED and [OII] based SFRs, the
decline in SSFR is roughly an order of magnitude while for the MIPS based SFRs,
the decline is a factor of ~4. We find approximately the same magnitude of
decline in SSFR even after removing the sample of galaxies near the cluster.
Galaxies in groups and a cluster at these redshifts therefore have lower star
formation (SF) activity than galaxies in the field, as is the case at z~0. We
investigated whether the decline in SFR with increasing density is caused by a
change in the proportion of quiescent and star forming galaxies (SFGs) or by a
decline in the SFRs of SFGs. Using the rest-frame U-V and V-J colors to
distinguish quiescent galaxies from SFGs we find the fraction of quiescent
galaxies increases from ~32% to 79% from low to high density. In addition, we
find the SSFRs of SFGs, selected based on U-V and V-J colors, to decline with
increasing density by factors of ~5-6 for the SED and [OII] based SFRs. The
MIPS based SSFRs for SFGs decline with a shallower slope. The order of
magnitude decline in the SSFR-density relation at 0.6<z<0.9 is therefore driven
by both a combination of declining SFRs of SFGs as well as a changing mix of
SFGs and quiescent galaxies [ABRIDGED].Comment: 21 pages, 15 figures, 2 tables, resubmitted to ApJ after addressing
referee comment
The Growth of Massive Galaxies Since z=2
We study the growth of massive galaxies from z=2 to the present using data
from the NEWFIRM Medium Band Survey. The sample is selected at a constant
number density of n=2x10^-4 Mpc^-3, so that galaxies at different epochs can be
compared in a meaningful way. We show that the stellar mass of galaxies at this
number density has increased by a factor of ~2 since z=2, following the
relation log(M)=11.45-0.15z. In order to determine at what physical radii this
mass growth occurred we construct very deep stacked rest-frame R-band images at
redshifts z=0.6, 1.1, 1.6, and 2.0. These image stacks of typically 70-80
galaxies enable us to characterize the stellar distribution to surface
brightness limits of ~28.5 mag/arcsec^2. We find that massive galaxies
gradually built up their outer regions over the past 10 Gyr. The mass within a
radius of r=5 kpc is nearly constant with redshift whereas the mass at 5-75 kpc
has increased by a factor of ~4 since z=2. Parameterizing the surface
brightness profiles we find that the effective radius and Sersic n parameter
evolve as r_e~(1+z)^-1.3 and n~(1+z)^-1.0 respectively. The data demonstrate
that massive galaxies have grown mostly inside-out, assembling their extended
stellar halos around compact, dense cores with possibly exponential radial
density distributions. Comparing the observed mass evolution to the average
star formation rates of the galaxies we find that the growth is likely
dominated by mergers, as in-situ star formation can only account for ~20% of
the mass build-up from z=2 to z=0. The main uncertainties in this study are
possible redshift-dependent systematic errors in the total stellar masses and
the conversion from light-weighted to mass-weighted radial profiles.Comment: Accepted for publication in the Astrophysical Journal. 26 pages, 13
figures in main tex
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