WOULD PEOPLE RATHER PAY TAXES OR TRADE TAXES TO PAY FOR ENVIRONMENTAL GOODS? A GROUND WATER QUALITY CASE

The potential sensitivity of environmental resource valuation to payment vehicles is of interest to researchers and decision-makers involved in estimating and applying these numbers. A conceptual model is developed which provides insight into how the different payment vehicles of a special tax and a tax reallocation affects the willingness to pay (WTP) for environmental goods. Hypothesis testing using contingent valuation data suggests WTP with a tax reallocation is higher than WTP with a special tax for ground water quality protection in Georgia and Maine.Environmental Economics and Policy, Public Economics,

The Subaru FMOS Galaxy Redshift Survey (FastSound). II. The Emission Line Catalog and Properties of Emission Line Galaxies

We present basic properties of $\sim$3,300 emission line galaxies detected by the FastSound survey, which are mostly H$\alpha$ emitters at $z \sim$ 1.2-1.5 in the total area of about 20 deg$^2$, with the H$\alpha$ flux sensitivity limit of $\sim 1.6 \times 10^{-16} \rm erg \ cm^{-2} s^{-1}$ at 4.5 sigma. This paper presents the catalogs of the FastSound emission lines and galaxies, which will be open to the public in the near future. We also present basic properties of typical FastSound H$\alpha$ emitters, which have H$\alpha$ luminosities of $10^{41.8}$-$10^{43.3}$ erg/s, SFRs of 20--500 $M_\odot$/yr, and stellar masses of $10^{10.0}$--$10^{11.3}$ $M_\odot$. The 3D distribution maps for the four fields of CFHTLS W1--4 are presented, clearly showing large scale clustering of galaxies at the scale of $\sim$ 100--600 comoving Mpc. Based on 1,105 galaxies with detections of multiple emission lines, we estimate that contamination of non-H$\alpha$ lines is about 4% in the single-line emission galaxies, which are mostly [OIII]$\lambda$5007. This contamination fraction is also confirmed by the stacked spectrum of all the FastSound spectra, in which H$\alpha$, [NII]$\lambda \lambda$6548,6583, [SII]$\lambda \lambda$6717, 6731, and [OI]$\lambda \lambda$6300,6364 are seen.Comment: 17 pages, 15 figures, accepted for publication in PAS

Numerical simulations of expanding supershells in dwarf irregular galaxies. I. Application to Holmberg I

Numerical hydrodynamical modelling of supernova-driven shell formation is performed with a purpose to reproduce a giant HI ring (diameter 1.7 kpc) in the dwarf irregular galaxy Holmberg I (Ho I). We find that the contrast in HI surface density between the central HI depression and the ring is sensitive to the shape of the gravitational potential. This circumstance can be used to constrain the total mass (including the dark matter halo) of nearly face-on dwarf irregulars. We consider two models of Ho I, which differ by an assumed mass of the dark matter halo M_h. The contrast in HI surface density between the central HI depression and the ring, as well as the lack of gas expansion in the central hole, are better reproduced by the model with a massive halo of M_h=6.0*10^9 M_sun than by that with a small halo of M_h=4.0*10^8 M_sun, implying that Ho I is halo-dominated. Assuming the halo mass of 6.0*10^9 M_sum, we determine the mechanical energy required to form the observed ring equal to (3.0 +- 0.5)*10^53 ergs, equivalent 300+-50 Type II supernovae. The inclination of Ho I is constrained to 15-20 degrees by comparing the modelled HI spectrum and channel maps with those observed.Comment: 11 pages, 11 figures, accepted for publication in Astronomy and Astrophysic

Very compact millimeter sizes for composite star-forming/AGN submillimeter galaxies

We report the study of far-IR sizes of submillimeter galaxies (SMGs) in relation to their dust-obscured star formation rate (SFR) and active galactic nuclei (AGN) presence, determined using mid-IR photometry. We determined the millimeter-wave ($\lambda_{\rm obs}=1100 \mu$m) sizes of 69 ALMA-identified SMGs, selected with $\geq10$$\sigma$ confidence on ALMA images ($F_{\rm 1100 \mu m}=1.7$--7.4 mJy). We found that all the SMGs are located above an avoidance region in the millimeter size-flux plane, as expected by the Eddington limit for star formation. In order to understand what drives the different millimeter-wave sizes in SMGs, we investigated the relation between millimeter-wave size and AGN fraction for 25 of our SMGs at $z=1$--3. We found that the SMGs for which the mid-IR emission is dominated by star formation or AGN have extended millimeter-sizes, with respective median $R_{\rm c,e} = 1.6^{+0.34}_{-0.21}$ and 1.5$^{+0.93}_{-0.24}$ kpc. Instead, the SMGs for which the mid-IR emission corresponds to star-forming/AGN composites have more compact millimeter-wave sizes, with median $R_{\rm c,e}=1.0^{+0.20}_{-0.20}$ kpc. The relation between millimeter-wave size and AGN fraction suggests that this size may be related to the evolutionary stage of the SMG. The very compact sizes for composite star-forming/AGN systems could be explained by supermassive black holes growing rapidly during the SMG coalescing, star-formation phase.Comment: 9 pages, 4 figures, 1 table. Accepted for publication in ApJ Lette

SXDF-UDS-CANDELS-ALMA 1.5 arcmin2^2 deep survey

We have conducted 1.1 mm ALMA observations of a contiguous $105'' \times 50''$ or 1.5 arcmin$^2$ window in the SXDF-UDS-CANDELS. We achieved a 5$\sigma$ sensitivity of 0.28 mJy, providing a flat sensus of dusty star-forming galaxies with $L_{\rm IR} \sim6\times10^{11}$ $L_\odot$ (for $T_{\rm dust}$ =40K) up to $z\sim10$ thanks to the negative K-correction at this wavelength. We detected 5 brightest sources (S/N$>$6) and 18 low-significance sources (5$>$S/N$>$4; these may contain spurious detections, though). One of the 5 brightest ALMA sources ($S_{\rm 1.1mm} = 0.84 \pm 0.09$ mJy) is extremely faint in the WFC3 and VLT/HAWK-I images, demonstrating that a contiguous ALMA imaging survey is able to uncover a faint dust-obscured population that is invisible in deep optical/near-infrared surveys. We found a possible [CII]-line emitter at $z=5.955$ or a low-$z$ CO emitting galaxy within the field, which may allow us to constrain the [CII] and/or the CO luminosity functions across the history of the universe.Comment: 4 pages, 2 figures, 1 table, to appear in the proceedings of IAU Symposium 319 "Galaxies at High Redshift and Their Evolution over Cosmic Time", eds. S. Kaviraj & H. Ferguso

SXDF-ALMA 2 Arcmin^2 Deep Survey: Resolving and Characterizing the Infrared Extragalactic Background Light Down to 0.5 mJy

We present a multi-wavelength analysis of five submillimeter sources (S_1.1mm = 0.54-2.02 mJy) that were detected during our 1.1-mm-deep continuum survey in the SXDF-UDS-CANDELS field (2 arcmin^2, 1sigma = 0.055 mJy beam^-1) using the Atacama Large Millimeter/submillimeter Array (ALMA). The two brightest sources correspond to a known single-dish (AzTEC) selected bright submillimeter galaxy (SMG), whereas the remaining three are faint SMGs newly uncovered by ALMA. If we exclude the two brightest sources, the contribution of the ALMA-detected faint SMGs to the infrared extragalactic background light is estimated to be ~ 4.1^{+5.4}_{-3.0} Jy deg^{-2}, which corresponds to ~ 16^{+22}_{-12}% of the infrared extragalactic background light. This suggests that their contribution to the infrared extragalactic background light is as large as that of bright SMGs. We identified multi-wavelength counterparts of the five ALMA sources. One of the sources (SXDF-ALMA3) is extremely faint in the optical to near-infrared region despite its infrared luminosity (L_IR ~ 1e12 L_sun or SFR ~ 100 M_sun yr^{-1}). By fitting the spectral energy distributions (SEDs) at the optical-to-near-infrared wavelengths of the remaining four ALMA sources, we obtained the photometric redshifts (z_photo) and stellar masses (M_*): z_photo ~ 1.3-2.5, M_* ~ (3.5-9.5)e10 M_sun. We also derived their star formation rates (SFRs) and specific SFRs (sSFRs) as ~ 30-200 M_sun yr^{-1} and ~ 0.8-2 Gyr^{-1}, respectively. These values imply that they are main-sequence star-forming galaxies.Comment: PASJ accepted, 15 pages, 6 figures, 2 table