1,304 research outputs found
Toward a Practical Estate-Tax Exclusion for Family-Run Businesses: Analysis of Section 2033A and Proposal for Reform
In a previous work appearing in this Journal, the authors proposed an approach to estate and gift taxation that encourages productive behavior by the recipients of wealth. In this Article, the authors analyze, in the context of their earlier work, the new estate-tax exclusion for closely held businesses (section 2033A) created by the Taxpayer Relief Act of 1997. The authors describe the features of a practical family-run business exclusion and conclude that section 2033A, in its present form, fails as a practical exclusion. The authors catalogue those elements of section 2033A that should be retained and propose reforms of those elements that should be eliminated or changed
The Proper Role of the Estate and Gift Taxation of Closely Held Businesses
The authors argue that the goals of estate and gift taxation are not served by taxing closely held businesses when the recipient of the business actively participates in its operation. Further, the authors suggest that taxing closely held businesses tends to harm capital production. The authors propose an approach to estate and gift taxation that encourages productive behavior by the recipients of wealth
Probing CDM cosmology with the Evolutionary Map of the Universe survey
The Evolutionary Map of the Universe (EMU) is an all-sky survey in
radio-continuum which uses the Australian SKA Pathfinder (ASKAP). Using galaxy
angular power spectrum and the integrated Sachs-Wolfe effect, we study the
potential of EMU to constrain models beyond CDM (i.e., local
primordial non-Gaussianity, dynamical dark energy, spatial curvature and
deviations from general relativity), for different design sensitivities. We
also include a multi-tracer analysis, distinguishing between star-forming
galaxies and galaxies with an active galactic nucleus, to further improve EMU's
potential. We find that EMU could measure the dark energy equation of state
parameters around 35\% more precisely than existing constraints, and that the
constraints on and modified gravity parameters will improve up to
a factor with respect to Planck and redshift space distortions
measurements. With this work we demonstrate the promising potential of EMU to
contribute to our understanding of the Universe.Comment: 15 pages (29 with references and appendices), 6 figures and 10
tables. Matches the published version. Minimal changes from previous versio
Possible Detection of OVI from the LMC Superbubble N70
We present FUSE observations toward four stars in the LMC superbubble N70 and
compare these spectra to those of four comparison targets located in nearby
field and diffuse regions. The N70 sight lines show OVI 1032 absorption that is
consistently stronger than the comparison sight lines by ~60%. We attribute the
excess column density (logN_OVI=14.03 cm^-2) to hot gas within N70, potentially
the first detection of OVI associated with a superbubble. In a survey of 12 LMC
sight lines, Howk et al. (2002a) concluded that there was no correlation
between ISM morphology and N_OVI. We present a reanalysis of their measurements
combined with our own and find a clear difference between the superbubble and
field samples. The five superbubbles probed to date with FUSE show a
consistently higher mean N_OVI than the 12 non-superbubble sight lines, though
both samples show equivalent scatter from halo variability. Possible ionization
mechanisms for N70 are discussed, and we conclude that the observed OVI could
be the product of thermal conduction at the interface between the hot, X-ray
emitting gas inside the superbubble and the cooler, photoionized material
making up the shell seen prominently in Halpha. We calculate the total hydrogen
density n_H implied by our OVI measurements and find a value consistent with
expectations. Finally, we discuss emission-line observations of OVI from N70.Comment: 9 pages in emulateapj style. Accepted to Ap
The Santa Fe Light Cone Simulation Project: II. The Prospects for Direct Detection of the WHIM with SZE Surveys
Detection of the Warm-Hot Intergalactic Medium (WHIM) using Sunyaev-Zeldovich
effect (SZE) surveys is an intriguing possibility, and one that may allow
observers to quantify the amount of "missing baryons" in the WHIM phase. We
estimate the necessary sensitivity for detecting low density WHIM gas with the
South Pole Telescope (SPT) and Planck Surveyor for a synthetic 100 square
degree sky survey. This survey is generated from a very large, high dynamic
range adaptive mesh refinement cosmological simulation performed with the Enzo
code. We find that for a modest increase in the SPT survey sensitivity (a
factor of 2-4), the WHIM gas makes a detectable contribution to the integrated
sky signal. For a Planck-like satellite, similar detections are possible with a
more significant increase in sensitivity (a factor of 8-10). We point out that
for the WHIM gas, the kinematic SZE signal can sometimes dominate the thermal
SZE where the thermal SZE decrement is maximal (150 GHz), and that using the
combination of the two increases the chance of WHIM detection using SZE
surveys. However, we find no evidence of unique features in the thermal SZE
angular power spectrum that may aid in its detection. Interestingly, there are
differences in the power spectrum of the kinematic SZE, which may not allow us
to detect the WHIM directly, but could be an important contaminant in
cosmological analyses of the kSZE-derived velocity field. Corrections derived
from numerical simulations may be necessary to account for this contamination.Comment: 9 pages, submitted to Astrophysical Journa
Cosmic Origins Spectrograph and FUSE Observations of T ~ 10^5 K Gas In A Nearby Galaxy Filament
We present a detection of a broad Ly-alpha absorber (BLA) with a matching O
VI line in the nearby universe. The BLA is detected at z = 0.01028 in the high
S/N spectrum of Mrk 290 obtained using the Cosmic Origins Spectrograph. The
Ly-alpha absorption has two components, with b(HI) = 55 +/- 1 km/s and b(HI) =
33 +/- 1 km/s, separated in velocity by v ~ 115 km/s. The O VI, detected by
FUSE at z = 0.01027, has a b(OVI) = 29 +/- 3 km/s and is kinematically well
aligned with the broader HI component. The different line widths of the BLA and
OVI suggest a temperature of T = 1.4 x 10^5 K in the absorber. The observed
line strength ratios and line widths favor an ionization scenario in which both
ion-electron collisions and UV photons contribute to the ionization in the gas.
Such a model requires a low-metallicity of -1.7 dex, ionization parameter of
log U ~ -1.4, a large total hydrogen column density of N(H) ~ 4 x 10^19 cm^-2,
and a path length of 400 kpc. The line of sight to Mrk 290 intercepts at the
redshift of the absorber, a megaparsec scale filamentary structure extending
over 20 deg in the sky, with several luminous galaxies distributed within 1.5
Mpc projected distance from the absorber. The collisionally ionized gas in this
absorber is likely tracing a shock-heated gaseous structure, consistent with a
few different scenarios for the origin, including an over-dense region of the
WHIM in the galaxy filament or highly ionized gas in the extended halo of one
of the galaxies in the filament. In general, BLAs with metals provide an
efficient means to study T ~ 10^5 - 10^6 K gas in galaxy halos and in the
intergalactic medium. A substantial fraction of the baryons "missing" from the
present universe is predicted to be in such environments in the form of highly
ionized plasma.Comment: Astrophysical Journal Accepte
The Ultraviolet Detection of Diffuse Gas in Galaxy Groups
A small survey of the UV-absorbing gas in 12 low- galaxy groups has been
conducted using the Cosmic Origins Spectrograph (COS) on-board the Hubble Space
Telescope (HST). Targets were selected from a large, homogeneously-selected
sample of groups found in the Sloan Digital Sky Survey (SDSS). A critical
selection criterion excluded sight lines that pass close ( virial radii)
to a group galaxy, to ensure absorber association with the group as a whole.
Deeper galaxy redshift observations are used both to search for closer galaxies
and also to characterize these to groups, the
most massive of which are highly-virialized with numerous early-type galaxies
(ETGs). This sample also includes two spiral-rich groups, not yet
fully-virialized. At group-centric impact parameters of 0.3-2 Mpc, these
-30 spectra detected HI absorption in 7 of 12 groups; high
(OVI) and low (SiIII) ion metal lines are present in 2/3 of the absorption
components. None of the three most highly-virialized, ETG-dominated groups are
detected in absorption. Covering fractions % are seen at all impact
parameters probed, but do not require large filling factors despite an enormous
extent. Unlike halo clouds in individual galaxies, group absorbers have radial
velocities which are too low to escape the group potential well without doubt.
This suggests that these groups are "closed boxes" for galactic evolution in
the current epoch. Evidence is presented that the cool and warm group absorbers
are not a pervasive intra-group medium (IGrM), requiring a hotter (
to K) IGrM to be present to close the baryon accounting.Comment: Resubmitted to ApJS after first review; 82 pages (27 for main text,
rest are Appendices and supplemental figures and tables), 47 figures, 21
table
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