In an increasingly globalized and interconnected world, where social and environmental change occur ever more rapidly, careful futures-oriented thinking becomes crucial for effective decision making. ...Foresight activities, including scenario development, quantitative modeling, and scenario-guided design of policies and programs, play a key role in exploring options to address socioeconomic and environmental challenges across many sectors and decision-making levels. We take stock of recent methodological developments in scenario and foresight exercises, seek to provide greater clarity on the many diverse approaches employed, and examine their use by decision makers in different fields and at different geographic, administrative, and temporal scales. Experience shows the importance of clearly formulated questions, structured dialog, carefully designed scenarios, sophisticated biophysical and socioeconomic analysis, and iteration as needed to more effectively link the growing scenarios and foresight community with today's decision makers and to better address the social, economic, and environmental challenges of tomorrow.
The Great Observatories All-sky LIRG Survey (GOALS) consists of a complete sample of 202 luminous infrared galaxies (LIRGs) selected from the IRAS Revised Bright Galaxy Sample (RBGS). The galaxies ...span the full range of interaction stages, from isolated galaxies to interacting pairs to late stage mergers. We present a comparison of the UV and infrared properties of 135 galaxies in GOALS observed by GALEX and Spitzer. For interacting galaxies with separations greater than the resolution of GALEX and Spitzer (~2''-6''), we assess the UV and IR properties of each galaxy individually. The contribution of the FUV to the measured star formation rate (SFR) ranges from 0.2% to 17.9%, with a median of 2.8% and a mean of 4.0% ± 0.4%. The specific star formation rate (SSFR) of the GOALS sample is extremely high, with a median value (3.9 × 10-10 yr-1) that is comparable to the highest SSFRs seen in the Spitzer Infrared Nearby Galaxies Survey sample. We examine the position of each galaxy on the IR excess-UV slope (IRX-beta) diagram as a function of galaxy properties, including IR luminosity and interaction stage. The LIRGs on average have greater IR excesses than would be expected based on their UV colors if they obeyed the same relations as starbursts with L IR < 1011 L sun or normal late-type galaxies. The ratio of L IR to the value one would estimate from the IRX-beta relation published for lower luminosity starburst galaxies ranges from 0.2 to 68, with a median value of 2.7. A minimum of 19% of the total IR luminosity in the RBGS is produced in LIRGs and ultraluminous infrared galaxies with red UV colors (beta>0). Among resolved interacting systems, 32% contain one galaxy which dominates the IR emission while the companion dominates the UV emission. Only 21% of the resolved systems contain a single galaxy which dominates both wavelengths.
Abstract
We describe a
Herschel Space Observatory
194–671
μ
m spectroscopic survey of a sample of 121 local luminous infrared galaxies and report the fluxes of the CO
J
to
J
–1 rotational transitions ...for
, the N
ii
205
μ
m line, the C
i
lines at 609 and 370
μ
m, as well as additional and usually fainter lines. The CO spectral line energy distributions (SLEDs) presented here are consistent with our earlier work, which was based on a smaller sample, that calls for two distinct molecular gas components in general: (i) a cold component, which emits CO lines primarily at
J
≲ 4 and likely represents the same gas phase traced by CO (1−0), and (ii) a warm component, which dominates over the mid-
J
regime (4 <
J
≲ 10) and is intimately related to current star formation. We present evidence that the CO line emission associated with an active galactic nucleus is significant only at
J
> 10. The flux ratios of the two C
i
lines imply modest excitation temperatures of 15–30 K; the C
i
370
μ
m line scales more linearly in flux with CO (4−3) than with CO (7−6). These findings suggest that the C
i
emission is predominantly associated with the gas component defined in (i) above. Our analysis of the stacked spectra in different far-infrared (FIR) color bins reveals an evolution of the SLED of the rotational transitions of
vapor as a function of the FIR color in a direction consistent with infrared photon pumping.
A sensitive broadband molecular line survey of the Sagittarius B2(N) star-forming region has been obtained with the Heterodyne Instrument for the Far-Infrared (HIFI) instrument on the Herschel Space ...Observatory, offering the first high spectral resolution look at this well-studied source in a wavelength region largely inaccessible from the ground (625-157 mu m). We present a local thermodynamic equilibrium (LTE) model to the spectral signatures of each molecule, constraining the source sizes for hot core species with complementary Submillimeter Array interferometric observations and assuming that molecules with related functional group composition are cospatial. Notably, we find significantly higher abundances of amine- and amide-bearing molecules (CH sub(3)NH sub(2), CH sub(2)NH, and NH sub(2)CHO) toward Sgr B2(N) than Orion KL and lower abundances of some complex oxygen-bearing molecules (CH sub(3)OCHO in particular). The reduced HIFI spectral scan and LTE model are made available to the public as a resource for future investigations of star-forming regions in the submillimeter and far-infrared.
In this paper, we present the measurements of the Nii 205 mu m line for a flux-limited sample of 122 (ultra-)luminous infrared galaxies (U)LIRGs and 20 additional normal galaxies, obtained with the ...Herschel Space Observatory (Herschel). We also investigate the relation between LNii205 mu m and star formation rate (SFR), and show that LNii205 mu m has a nearly linear correlation with SFR, albeit the intercept of such a relation varies somewhat with ${f}_{60}/{f}_{100}$, consistent with our previous conclusion that Nii 205 mu m emission can serve as an SFR indicator with an accuracy of ~0.4 dex, or ~0.2 dex if ${f}_{60}/{f}_{100}$ is known independently. Finally, we determine the electron densities (ne) of the ionized medium for a subsample of 12 (U)LIRGs with both Nii 205 mu m and Nii 122 mu m data, and find that ne is in the range of ~1-100 cm-3, with a median value of 22 cm-3.
normal, i.e. satisfies a monotone convergence theorem, for the von Neumann subalgebra. Flat tori, noncommutative tori, and a link with the QUE property of manifolds are given as examples.
The integral in noncommutative geometry (NCG) involves a non-standard trace called a Dixmier trace. The geometric origins of this integral are well known. From a measure-theoretic view, however, the ...formulation contains several difficulties. We review results concerning the technical features of the integral in NCG and some outstanding problems in this area. The review is aimed for the general user of NCG.
Since 9/11, many western nations have re-framed their national security decisions in terms of strategic risk management. All have undertaken risk assessments, but valid translation into capability ...priorities has been abdicated largely by transferring priorities directly from risk magnitudes. Treatment priorities should be determined from risk reduction benefits in relation to costs, but a method for assessing risk reduction effects has been broadly elusive. This article shows, in a pragmatic way, how treatment options are generated, and how the capabilities that contribute most to risk reduction can be identified. These should be priority targets for the investment of limited resources.
We investigate the properties of the singular values of the quantised derivatives of essentially bounded functions on Rd with d>1. The commutator isgn(D),1⊗Mf of an essentially bounded function f on ...Rd acting by pointwise multiplication on L2(Rd) and the sign of the Dirac operator D acting on C2⌊d/2⌋⊗L2(Rd) is called the quantised derivative of f. We prove the condition that the function x↦‖(∇f)(x)‖2d:=((∂1f)(x)2+…+(∂df)(x)2)d/2, x∈Rd, being integrable is necessary and sufficient for the quantised derivative of f to belong to the weak Schatten d-class. This problem has been previously studied by Rochberg and Semmes, and is also explored in a paper of Connes, Sullivan and Telemann. Here we give new and complete proofs using the methods of double operator integrals. Furthermore, we prove a formula for the Dixmier trace of the d-th power of the absolute value of the quantised derivative. For real valued f, when x↦‖(∇f)(x)‖2d is integrable, there exists a constant cd>0 such that for every continuous normalised trace φ on the weak trace class L1,∞ we have φ(|sgn(D),1⊗Mf|d)=cd∫Rd‖(∇f)(x)‖2ddx.
We present a study of the nearby Seyfert galaxy NGC 1068 using mid- and far-infrared data acquired with the IRAC, IRS, and MIPS instruments aboard the Spitzer Space Telescope. The images show ...extensive 8 and 24 mm emission coinciding with star formation in the inner spiral approximately 15'' (1 kpc) from the nucleus and a bright complex of star formation ~47'' (3 kpc) southwest of the nucleus. The brightest 8 mm polycyclic aromatic hydrocarbon (PAH) emission regions coincide remarkably well with knots observed in an Ha image. Strong PAH features at 6.2, 7.7, 8.6, and 11.3 mm are detected in IRS spectra measured at numerous locations inside, within, and outside the inner spiral. The IRAC colors and IRS spectra of these regions rule out dust heated by the active galactic nucleus (AGN) as the primary emission source; the spectral energy distributions are dominated by starlight and PAH emission. The equivalent widths and flux ratios of the PAH features in the inner spiral are generally consistent with conditions in a typical spiral galaxy interstellar medium (ISM). Interior to the inner spiral, the influence of the AGN on the ISM is evident via PAH flux ratios indicative of a higher ionization parameter and a significantly smaller mean equivalent width than observed in the inner spiral. The brightest 8 and 24 mm emission peaks in the disk of the galaxy, even at distances beyond the inner spiral, are located within the ionization cones traced by O III/Hb, and they are also remarkably well aligned with the axis of the radio jets. Although it is possible that radiation from the AGN may directly enhance PAH excitation or trigger the formation of OB stars that subsequently excite PAH emission at these locations in the inner spiral, the orientation of collimated radiation from the AGN and star formation knots in the inner spiral could be coincidental. The brightest PAH- and 24 mm-emitting regions are also located precisely where two spiral arms of molecular gas emerge from the ends of the inner stellar bar; this is consistent with kinematic models that predict maxima in the accumulation and compression of the ISM, where gas gets trapped within the inner Lindblad resonance of a large stellar bar that contains a smaller, weaker bar.
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![THE [N ii] 205 μm EMISSION ...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/0004-637X_1538-4357/small "THE [N ii] 205 μm EMISSION IN LOCAL LUMINOUS INFRARED GALAXIES")
