3,024 research outputs found
Article Addendum: Ecocultural basis of cognition: Farmers and fishermen are more holistic than herders
It has been hypothesized that interdependent (versus independent) social orientations breed more holistic (versus analytic) cognitions. If so, farming and small-scale fishing, which require more cooperation (and represent a more interdependent mode of being) than does herding, may encourage a more holistic mode of cognition. To test this hypothesis we compared responses to tasks measuring categorization, reasoning, and attention by members of herding, fishing, and farming communities in the eastern Black Sea Region of Turkey. The samples did not differ from each other in important demographic variables such as nationality, ethnicity, language, and religion, as well as age and education. As hypothesized, in all three tasks, results indicated a greater degree of holistic mode of cognition exhibited by the members of fishing and farming communities than members of herding communities. The findings support the notion that level of special interdependence fostered by ecocultural settings is likely to shape the ways in which individuals perceive and attend to their surrounding world
Systematic Errors in the Hubble Constant Measurement from the Sunyaev-Zel'dovich effect
The Hubble constant estimated from the combined analysis of the
Sunyaev-Zel'dovich effect and X-ray observations of galaxy clusters is
systematically lower than those from other methods by 10-15 percent. We examine
the origin of the systematic underestimate using an analytic model of the
intracluster medium (ICM), and compare the prediction with idealistic triaxial
models and with clusters extracted from cosmological hydrodynamical
simulations. We identify three important sources for the systematic errors;
density and temperature inhomogeneities in the ICM, departures from
isothermality, and asphericity. In particular, the combination of the first two
leads to the systematic underestimate of the ICM spectroscopic temperature
relative to its emission-weighed one. We find that these three systematics well
reproduce both the observed bias and the intrinsic dispersions of the Hubble
constant estimated from the Sunyaev-Zel'dovich effect.Comment: 26 pages, 7 figures, accepted for publication in ApJ, Minor change
Investigating the hard X-ray emission from the hottest Abell cluster A2163 with Suzaku
We present the results from Suzaku observations of the hottest Abell galaxy
cluster A2163 at . To study the physics of gas heating in cluster
mergers, we investigated hard X-ray emission from the merging cluster A2163,
which hosts the brightest synchrotron radio halo. We analyzed hard X-ray
spectra accumulated from two-pointed Suzaku observations. Non-thermal hard
X-ray emission should result from the inverse Compton (IC) scattering of
relativistic electrons by the CMB photons. To measure this emission, the
dominant thermal emission in the hard X-ray band must be modeled in detail. To
this end, we analyzed the combined broad-band X-ray data of A2163 collected by
Suzaku and XMM-Newton, assuming single- and multi-temperature models for
thermal emission and the power-law model for non-thermal emission. From the
Suzaku data, we detected significant hard X-ray emission from A2163 in the
12-60 keV band at the level (or at the level if a
systematic error is considered). The Suzaku HXD spectrum alone is consistent
with the single-T thermal model of gas temperature keV. From the XMM
data, we constructed a multi-T model including a very hot ( keV)
component in the NE region. Incorporating the multi-T and the power-law models
into a two-component model with a radio-band photon index, the 12-60 keV energy
flux of non-thermal emission is constrained within . The 90% upper limit of detected IC
emission is marginal ( in the
12-60 keV). The estimated magnetic field in A2163 is .
While the present results represent a three-fold increase in the accuracy of
the broad band spectral model of A2163, more sensitive hard X-ray observations
are needed to decisively test for the presence of hard X-ray emission due to IC
emission.Comment: 7 pages, 7 figures, A&A accepted. Minor correctio
Imaging Simulations of the Sunyaev-Zel'dovich Effect for ALMA
We present imaging simulations of the Sunyaev-Zel'dovich effect of galaxy
clusters for the Atacama Large Millimeter/submillimeter Array (ALMA) including
the Atacama Compact Array (ACA). In its most compact configuration at 90GHz,
ALMA will resolve the intracluster medium with an effective angular resolution
of 5 arcsec. It will provide a unique probe of shock fronts and relativistic
electrons produced during cluster mergers at high redshifts, that are hard to
spatially resolve by current and near-future X-ray detectors. Quality of image
reconstruction is poor with the 12m array alone but improved significantly by
adding ACA; expected sensitivity of the 12m array based on the thermal noise is
not valid for the Sunyaev-Zel'dovich effect mapping unless accompanied by an
ACA observation of at least equal duration. The observations above 100 GHz will
become excessively time-consuming owing to the narrower beam size and the
higher system temperature. On the other hand, significant improvement of the
observing efficiency is expected once Band 1 is implemented in the future.Comment: 16 pages, 12 figures. Accepted for publication in PASJ. Note added in
proof is include
START: Smoothed particle hydrodynamics with tree-based accelerated radiative transfer
We present a novel radiation hydrodynamics code, START, which is a smoothed
particle hydrodynamics (SPH) scheme coupled with accelerated radiative
transfer. The basic idea for the acceleration of radiative transfer is parallel
to the tree algorithm that is hitherto used to speed up the gravitational force
calculation in an N-body system. It is demonstrated that the radiative transfer
calculations can be dramatically accelerated, where the computational time is
scaled as Np log Ns for Np SPH particles and Ns radiation sources. Such
acceleration allows us to readily include not only numerous sources but also
scattering photons, even if the total number of radiation sources is comparable
to that of SPH particles. Here, a test simulation is presented for a multiple
source problem, where the results with START are compared to those with a
radiation SPH code without tree-based acceleration. We find that the results
agree well with each other if we set the tolerance parameter as < 1.0, and then
it demonstrates that START can solve radiative transfer faster without reducing
the accuracy. One of important applications with START is to solve the transfer
of diffuse ionizing photons, where each SPH particle is regarded as an emitter.
To illustrate the competence of START, we simulate the shadowing effect by
dense clumps around an ionizing source. As a result, it is found that the
erosion of shadows by diffuse recombination photons can be solved. Such an
effect is of great significance to reveal the cosmic reionization process.Comment: 14 pages, 23 figures, accepted for publication in MNRA
Quasi-hydrostatic intracluster gas under radiative cooling
Quasi-hydrostatic cooling of the intracluster gas is studied. In the
quasi-hydrostatic model, work done by gravity on the inflow gas with dP \neq 0,
where P is the gas pressure, is taken into account in the thermal balance. The
gas flows in from the outer part so as to compensate the pressure loss of the
gas undergoing radiative cooling, but the mass flow is so moderate and smooth
that the gas is considered to be quasi-hydrostatic. The temperature of the
cooling gas decreases toward the cluster center, but, unlike cooling flows with
dP = 0, approaches a constant temperature of \sim 1/3 the temperature of the
non-cooling ambient gas. This does not mean that gravitational work cancels out
radiative cooling, but means that the temperature of the cooling gas appears to
approach a constant value toward the cluster center if the gas maintains the
quasi-hydrostatic balance. We discuss the mass flow in quasi-hydrostatic
cooling, and compare it with the standard isobaric cooling flow model. We also
discuss the implication of \dot{M} for the standard cooling flow model.Comment: 5 pages, 1 figure, accepted for publication in A&
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The Use of Effectiveness Monitoring and Reporting for Fish and Wildlife Habitat Restoration Within the Collaborative Forest Landscape Restoration Program 2010-2018
The Collaborative Forest Landscape Restoration Program (CFLRP) is a collection of large-scale restoration projects across the United States that are striving to improve many economic, social, and ecological sustainability issues, including the condition of fish and wildlife habitat. Effectiveness monitoring is a specific type of monitoring that is critically important in restoration because it is how managers and stakeholders discover the extent to which the outcomes of a project meet the intended goals, which forms the basis for adaptive management. The purpose of this case study is to create a baseline status assessment on the use of effectiveness monitoring and reporting for fish and wildlife habitat restoration in the CFLRP in order to help begin a discussion about how these processes might be improved. The objective of this case study is to synthesize the projects’ responses from the 2014 Ecological Indicator Report and the 2018 Annual Report to answer the following three questions: (1) Do the projects believe they have made good progress towards their fish and wildlife habitat restoration goals, and what information have they used to make this determination? (2) What are the projects’ specific habitat restoration goals and focal animal species? (3) How many of the projects have used effectiveness monitoring? Approximately half of the projects believe they are making good progress towards their fish and wildlife habitat restoration goals, and most of the rest believe they are making fair progress. The projects have used a variety of information to make these determinations, but they’ve depended most heavily on FACTS and WIT, two Forest Service databases that track forest and watershed improvement activities. Across the program, the projects have declared a variety of different habitat restoration goals and focal animal species, with the most common emphasis placed on open forest habitat, special status species, and birds. According to the information in the reports, 65% of projects are accomplishing or on their way to accomplishing effectiveness monitoring for wildlife habitat and 22% of projects are accomplishing or on their way to accomplishing effectiveness monitoring for fish habitat. However, it is unclear from these reports whether 13% of the projects are doing effectiveness monitoring for wildlife habitat and whether 22% of the projects are doing effectiveness monitoring for fish habitat. This uncertainty points to a weakness at the interface between monitoring and reporting. In 2018, I worked with the Forest Service to develop a more detailed and standardized reporting template to gather accurate information on the use of effectiveness monitoring for fish and wildlife habitat in the CFLRP. I provide a copy of this revised reporting template, describe the process of how it was developed, and describe how it will help improve restoration outcomes in the CFLRP. I recommend that this new template be completed by all the projects in 2019, and that response data be subsequently analyzed and shared with the public
The Sunyaev-Zel'dovich Effect at Five Arc-seconds: RXJ1347.5-1145 Imaged by ALMA
We present the first image of the thermal Sunyaev-Zel'dovich effect (SZE)
obtained by the Atacama Large Millimeter/submillimeter Array (ALMA). Combining
7-m and 12-m arrays in Band 3, we create an SZE map toward a galaxy cluster
RXJ1347.5-1145 with 5 arc-second resolution (corresponding to the physical size
of 20 kpc/h), the highest angular and physical spatial resolutions achieved to
date for imaging the SZE, while retaining extended signals out to 40
arc-seconds. The 1-sigma statistical sensitivity of the image is 0.017 mJy/beam
or 0.12 mK_CMB at the 5 arc-second full width at half maximum. The SZE image
shows a good agreement with an electron pressure map reconstructed
independently from the X-ray data and offers a new probe of the small-scale
structure of the intracluster medium. Our results demonstrate that ALMA is a
powerful instrument for imaging the SZE in compact galaxy clusters with
unprecedented angular resolution and sensitivity. As the first report on the
detection of the SZE by ALMA, we present detailed analysis procedures including
corrections for the missing flux, to provide guiding methods for analyzing and
interpreting future SZE images by ALMA.Comment: 20 pages, 13 figures. Accepted for publication in PAS
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