63 research outputs found
Circumstances Under Which a Court Will Dismiss a Chapter 11 Filing Made in Bad Faith
(Excerpt)
Under section 1112(b) of title 11 of the United States Code (the “Bankruptcy Code”), a bankruptcy court may dismiss a Chapter 11 filing “for cause.” It is a generally accepted principle that “for cause” dismissal includes dismissal of filings made in bad faith, and this concept originates in a need for bankruptcy courts to uphold the jurisdictional integrity of the Chapter 11 process from those who would seek to abuse it. Courts deciding whether dismissal for bad faith is warranted typically employ a two-step analysis: first to determine whether a bad faith filing is “cause” for dismissal under section 1112(b) and second whether dismissal is “in the best interests of creditors and the estate.”
This memorandum explores the considerations made by bankruptcy courts when deciding whether to dismiss a bad faith Chapter 11 filing. Part I explains the origin and purpose of the good faith requirement. Part II analyzes how courts determine whether such dismissal is warranted and examines case law that exemplifies how various bankruptcy courts have approached the issue
Biogenic Sulfur Gases as Biosignatures on Temperate Sub-Neptune Waterworlds
Theoretical predictions and observational data indicate a class of sub-Neptune exoplanets may have water-rich interiors covered by hydrogen-dominated atmospheres. Provided suitable climate conditions, such planets could host surface liquid oceans. Motivated by recent JWST observations of K2-18 b, we self-consistently model the photochemistry and potential detectability of biogenic sulfur gases in the atmospheres of temperate sub-Neptune waterworlds for the first time. On Earth today, organic sulfur compounds produced by marine biota are rapidly destroyed by photochemical processes before they can accumulate to significant levels. Domagal-Goldman et al. suggest that detectable biogenic sulfur signatures could emerge in Archean-like atmospheres with higher biological production or low UV flux. In this study, we explore biogenic sulfur across a wide range of biological fluxes and stellar UV environments. Critically, the main photochemical sinks are absent on the nightside of tidally locked planets. To address this, we further perform experiments with a 3D general circulation model and a 2D photochemical model (VULCAN 2D) to simulate the global distribution of biogenic gases to investigate their terminator concentrations as seen via transmission spectroscopy. Our models indicate that biogenic sulfur gases can rise to potentially detectable levels on hydrogen-rich water worlds, but only for enhanced global biosulfur flux (≳20 times modern Earth's flux). We find that it is challenging to identify DMS at 3.4 μm where it strongly overlaps with CH4, whereas it is more plausible to detect DMS and companion byproducts, ethylene (C2H4) and ethane (C2H6), in the mid-infrared between 9 and 13 μm
Biogenic Sulfur Gases as Biosignatures on Temperate Sub-Neptune Waterworlds
Theoretical predictions and observational data indicate a class of sub-Neptune exoplanets may have water-rich interiors covered by hydrogen-dominated atmospheres. Provided suitable climate conditions, such planets could host surface liquid oceans. Motivated by recent JWST observations of K2-18 b, we self-consistently model the photochemistry and potential detectability of biogenic sulfur gases in the atmospheres of temperate sub-Neptune waterworlds for the first time. On Earth today, organic sulfur compounds produced by marine biota are rapidly destroyed by photochemical processes before they can accumulate to significant levels. Domagal-Goldman et al. suggest that detectable biogenic sulfur signatures could emerge in Archean-like atmospheres with higher biological production or low UV flux. In this study, we explore biogenic sulfur across a wide range of biological fluxes and stellar UV environments. Critically, the main photochemical sinks are absent on the nightside of tidally locked planets. To address this, we further perform experiments with a 3D general circulation model and a 2D photochemical model (VULCAN 2D) to simulate the global distribution of biogenic gases to investigate their terminator concentrations as seen via transmission spectroscopy. Our models indicate that biogenic sulfur gases can rise to potentially detectable levels on hydrogen-rich water worlds, but only for enhanced global biosulfur flux (≳20 times modern Earth’s flux). We find that it is challenging to identify DMS at 3.4 μm where it strongly overlaps with CH4, whereas it is more plausible to detect DMS and companion byproducts, ethylene (C2H4) and ethane (C2H6), in the mid-infrared between 9 and 13 μm
The Case and Context for Atmospheric Methane as an Exoplanet Biosignature
Methane has been proposed as an exoplanet biosignature. Imminent observations
with the James Webb Space Telescope may enable methane detections on
potentially habitable exoplanets, so it is essential to assess in what
planetary contexts methane is a compelling biosignature. Methane's short
photochemical lifetime in terrestrial planet atmospheres implies that abundant
methane requires large replenishment fluxes. While methane can be produced by a
variety of abiotic mechanisms such as outgassing, serpentinizing reactions, and
impacts, we argue that, in contrast to an Earth-like biosphere, known abiotic
processes cannot easily generate atmospheres rich in CH and CO with
limited CO due to the strong redox disequilibrium between CH and CO.
Methane is thus more likely to be biogenic for planets with 1) a terrestrial
bulk density, high mean-molecular-weight and anoxic atmosphere, and an old host
star; 2) an abundance of CH that implies surface fluxes exceeding what
could be supplied by abiotic processes; and 3) atmospheric CO with
comparatively little CO.Comment: 10 pages, 5 figures, 15 pages Supplementary Information, 3
Supplementary Figure
JWST observations of K2-18b can be explained by a gas-rich mini-Neptune with no habitable surface
JWST recently measured the transmission spectrum of K2-18b, a habitable-zone
sub-Neptune exoplanet, detecting CH and CO in its atmosphere. The
discovery paper argued the data are best explained by a habitable "Hycean"
world, consisting of a relatively thin H-dominated atmosphere overlying a
liquid water ocean. Here, we use photochemical and climate models to simulate
K2-18b as both a Hycean planet and a gas-rich mini-Neptune with no defined
surface. We find that a lifeless Hycean world is hard to reconcile with the
JWST observations because photochemistry only supports part-per-million
CH in such an atmosphere while the data suggest about of the gas
is present. Sustaining %-level CH on a Hycean K2-18b may require the
presence of a methane-producing biosphere, similar to microbial life on Earth
billion years ago. On the other hand, we predict that a gas-rich
mini-Neptune with solar metallicity should have 4% CH and
nearly 0.1% CO, which are compatible with the JWST data. The CH and
CO are produced thermochemically in the deep atmosphere and mixed upward to
the low pressures sensitive to transmission spectroscopy. The model predicts
HO, NH and CO abundances broadly consistent with the non-detections.
Given the additional obstacles to maintaining a stable temperate climate on
Hycean worlds due to H escape and potential supercriticality at depth, we
favor the mini-Neptune interpretation because of its relative simplicity and
because it does not need a biosphere or other unknown source of methane to
explain the data.Comment: Accepted for publication at ApJ
A 2-D Magnetotelluric Investigation of the Cascadia Subduction Zone
39 pages. A thesis presented to the Department of Physics and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016.I have produced four 2-D magnetotelluric conductivity inversions of MOCHA
data roughly between the latitudes of 43N and 46N that indicate fluid variation along
strike in the Cascadia subduction zone. I directly compare these results to Wannamaker
et al. 2014 EMSLAB inversion and find the models to be very similar despite the use of
different data sets and inversion methods. Conductivity structure along the plate
interface supports the hypothesis that there is "partial creeping" occurring in the locked
zone in central Cascadia, as well as the possible presence of a secondary, inboard
locked zone at 44.5N in the ETS region. The variability of conductivity along strike also
suggests a more permeable crust in the northern region of Cascadia directly overhead
the ETS zone, and more fluid accumulation in this same region. This study indicates
that a more permeable overlying crust, combined with larger amounts of fluid present
may be critical components of rapid ETS occurrence
Circumstances Under Which a Court Will Dismiss a Chapter 11 Filing Made in Bad Faith
(Excerpt)
Under section 1112(b) of title 11 of the United States Code (the “Bankruptcy Code”), a bankruptcy court may dismiss a Chapter 11 filing “for cause.” It is a generally accepted principle that “for cause” dismissal includes dismissal of filings made in bad faith, and this concept originates in a need for bankruptcy courts to uphold the jurisdictional integrity of the Chapter 11 process from those who would seek to abuse it. Courts deciding whether dismissal for bad faith is warranted typically employ a two-step analysis: first to determine whether a bad faith filing is “cause” for dismissal under section 1112(b) and second whether dismissal is “in the best interests of creditors and the estate.”
This memorandum explores the considerations made by bankruptcy courts when deciding whether to dismiss a bad faith Chapter 11 filing. Part I explains the origin and purpose of the good faith requirement. Part II analyzes how courts determine whether such dismissal is warranted and examines case law that exemplifies how various bankruptcy courts have approached the issue
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