7,118 research outputs found
DEVELOPING COUNTRY PERSPECTIVE: SOUTHERN AGRICULTURE AND THE WORLD ECONOMY: THE MULTILATERAL TRADE NEGOTIATIONS
International Relations/Trade,
Are There Lessons from the Polish Agricultural Reform that Are Applicable to the Soviet Union?
International Development, International Relations/Trade,
The Adoption of Medications in Substance Abuse Treatment: Associations With Organizational Characteristics
Highlights findings from a study of the use of phamacotherapies to treat substance abuse and the factors that affect their adoption by treatment organizations. Analyzes patterns by type of medication, type of organization, and accreditation
Extending the redshift distribution of submm galaxies: Identification of a z~4 submm galaxy
We present the identification of a bright submillimeter galaxy (SMG) in the
field of Abell 2218. The galaxy has a spectroscopic redshift of ~4, and is
currently the highest redshift SMG known. It is detected at all wavelengths
from optical to submm, including the Spitzer IRAC bands. We discuss the
properties of this galaxy, which is undergoing intense star formation at a
rate~600 Msun/yr. We also compare the properties to those of radio-preselected
submm-bright galaxies. The z~4 result extends the redshift distribution of
SMGs.Comment: 4 pages, 4 figures, uses asp2004.sty. To appear in the proceedings of
the conference "Infrared Diagnostics of Galaxy Evolution", Pasadena, CA,
14-16 November 2005, ed. R. Char
A Submillimeter Selected Quasar in the Field of Abell 478
We report the discovery of a z=2.83 quasar in the field of the cooling flow
galaxy cluster Abell 478. This quasar was first detected in a submm survey of
star forming galaxies at high redshifts, as the brightest source. We discuss
the optical spectrum and far-IR spectral energy distribution (SED) of this
object.Comment: 4 pages, 3 figures, in "Deep Millimeter Surveys: Implications for
Galaxy Formation and Evolution", ed. J. Lowenthal and D. Hughes, World
Scientific Publisher
Gravitationally lensed radio emission associated with SMM J16359+6612, a multiply imaged submillimeter galaxy behind A2218
We report the detection of discrete, lensed radio emission from the multiply
imaged, z=2.516 submillimetre selected galaxy, SMM J16359+6612. All three
images are detected in deep WSRT 1.4 GHz and VLA 8.2 GHz observations, and the
radio positions are coincident with previous sub-mm SCUBA observations of this
system. This is the widest separation lens system to be detected in the radio
so far, and the first time that multiply imaged lensed radio emission has been
detected from a star forming galaxy -- all previous multiply-lensed radio
systems being associated with radio-loud AGN. Taking into account the total
magnification of ~45, the WSRT 1.4 GHz observations suggest a star formation
rate of 500 Solar mass/yr. The source has a steep radio spectrum (alpha -0.7)
and an intrinsic flux density of just 3 microJy at 8.2 GHz. Three other SCUBA
sources in the field are also detected by the WSRT, including SMMJ16359+66118,
a singly imaged (and magnified) arclet at z=1.034. Higher resolution radio
observations of SMMJ16359+6612 (and other highly magnified star forming
galaxies) provide a unique opportunity to study the general properties and
radio morphology of intrinsically faint, distant and obscured star forming
galaxies. They can also help to constrain the technical specification of next
generation radio telescopes, such as the Square Kilometre Array.Comment: 5 pages, 2 figures, to appear in A&A letter
Physical properties and morphology of a newly identified compact z=4.04 lensed submillimeter galaxy in Abell 2218
We present the identification of a bright submm source, SMMJ163555.5+661300,
detected in the lensing cluster Abell2218, for which we have accurately
determined the position using observations from the Submillimeter Array (SMA).
The identified optical counterpart has a spectroscopic redshift of
z=4.044+-0.001 if we attribute the single emission line detected at
lambda=6140AA to Lyman-alpha. This redshift identification is in good agreement
with the optical/near-infrared photometric redshift as well as the submm flux
ratio S_450/S_850~1.6, the radio-submm flux ratio S_1.4/S_850 < 0.004, and the
24um to 850um flux ratio S_24/S_850 < 0.005. Correcting for the gravitational
lensing amplification of ~5.5, we find that the source has a far-infrared
luminosity of 1.3x10^12 Lsun, which implies a star formation rate of 230
Msun/yr. This makes it the lowest-luminosity SMG known at z>4 to date. Previous
CO(4-3) emission line obserations yielded a non-detection, for which we derived
an upper limit of the CO line luminosity of L'_CO = 0.3x10^10 K km/s/pc^2,
which is not inconsistent with the L'_CO - L_FIR relation for starburst
galaxies. The best fit model to the optical and near-infrared photometry give a
stellar population with an age of 1.4 Gyr and a stellar mass of 1.6x10^10 Msun.
The optical morphology is compact and in the source plane the galaxy has an
extent of ~6kpc x 3kpc with individual star forming knots of <500 pc in size.
J163556 is not resolved in the SMA data and we place a strict upper limit on
the size of the starburst region of 8kpc x 3kpc, which implies a lower limit on
the star formation rate surface density of 12 Msun/yr/kpc^2. The redshift of
J163556 extends the redshift distribution of faint, lensed SMGs, and we find no
evidence that these have a different redshift distribution than bright SMGs.Comment: Accepted for publication in ApJ. 11 pages, 7 figure
The SCUBA-2 850 follow-up of WISE-selected, luminous dust-obscured quasars
Hot dust-obscured galaxies (Hot DOGs) are a new population recently
discovered in the \wise All-Sky survey. Multiwavelength follow-up observations
suggest that they are luminous, dust-obscured quasars at high redshift. Here we
present the JCMT SCUBA-2 850 follow-up observations of 10 Hot DOGs.
Four out of ten Hot DOGs have been detected at level. Based on the
IR SED decomposition approach, we derive the IR luminosities of AGN torus and
cold dust components. Hot DOGs in our sample are extremely luminous with most
of them having . The torus emissions
dominate the total IR energy output. However, the cold dust contribution is
still non-negligible, with the fraction of the cold dust contribution to the
total IR luminosity being dependent on the choice of torus
model. The derived cold dust temperatures in Hot DOGs are comparable to those
in UV bright quasars with similar IR luminosity, but much higher than those in
SMGs. Higher dust temperatures in Hot DOGs may be due to the more intense
radiation field caused by intense starburst and obscured AGN activities.
Fourteen and five submillimeter serendipitous sources in the 10 SCUBA-2 fields
around Hot DOGs have been detected at and levels,
respectively. By estimating their cumulative number counts, we confirm the
previous argument that Hot DOGs lie in dense environments. Our results support
the scenario in which Hot DOGs are luminous, dust-obscured quasars lying in
dense environments, and being in the transition phase between extreme starburst
and UV-bright quasars.Comment: 26 pages, 7 figures, PASP accepte
Did the Revolution Start Without Us? An Examination of Inclusive School Psychology Practice in Iowa and Nebraska
An investigation of inclusion practices was conducted through a mailed survey to 475 school psychologists working in Iowa and Nebraska. After an initial mailing and three follow up mailings, a usable return rate of 71% was obtained
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