The Seyfert 1 galaxy Arp 151 was monitored as part of three reverberation mapping campaigns spanning 2008-2015. We present modeling of these velocity-resolved reverberation mapping data sets using a ...geometric and dynamical model for the broad-line region (BLR). By modeling each of the three data sets independently, we infer the evolution of the BLR structure in Arp 151 over a total of 7 yr and constrain the systematic uncertainties in nonvarying parameters such as the black hole mass. We find that the BLR geometry of a thick disk viewed close to face-on is stable over this time, although the size of the BLR grows by a factor of ∼2. The dynamics of the BLR are dominated by inflow, and the inferred black hole mass is consistent for the three data sets, despite the increase in BLR size. Combining the inference for the three data sets yields a black hole mass and statistical uncertainty of log10( / ) = with a standard deviation in individual measurements of 0.13 dex.
As part of the Deep Convective Cloud and Chemistry (DC3) experiment, the National Science Foundation/National Center for Atmospheric Research (NCAR) Gulfstream‐V (GV) and NASA DC‐8 research aircraft ...probed the chemical composition of the inflow and outflow of two convective storms (north storm, NS, south storm, SS) originating in the Colorado region on 22 June 2012, a time when the High Park wildfire was active in the area. A wide range of trace species were measured on board both aircraft including biomass burning (BB) tracers hydrogen cyanide (HCN) and acetonitrile (ACN). Acrolein, a much shorter lived tracer for BB, was also quantified on the GV. The data demonstrated that the NS had ingested fresh smoke from the High Park fire and as a consequence had a higher VOC OH reactivity than the SS. The SS lofted aged fire tracers along with other boundary layer ozone precursors and was more impacted by lightning NOx (LNOx) than the NS. The NCAR master mechanism box model was initialized with measurements made in the outflow of the two storms. The NS and SS were predicted to produce 11 and 14 ppbv of O3, respectively, downwind of the storm over 2 days. Sensitivity tests revealed that the ozone production potential of the SS was highly dependent on LNOx. Normalized excess mixing ratios, ΔX/ΔCO, for HCN and ACN were determined in both the fire plume and the storm outflow and found to be 7.0 ± 0.5 and 2.3 ± 0.5 pptv ppbv−1, respectively, and 1.4 ± 0.3 pptv ppbv−1 for acrolein in the outflow only.
Key Points
Lightning NOx is a key driver of ozone production in storm outflows
Storms can transport biomass burning emissions to the upper troposphere
Acrolein is shown to be a good tracer for fresh biomass burning emissions
ABSTRACT
We present a deep XMM−Newton observation of the extremely massive, rapidly rotating, relativistic-jet-launching spiral galaxy 2MASX J23453268−0449256. Diffuse X-ray emission from the hot ...gaseous halo around the galaxy is robustly detected out to a radius of 160 kpc, corresponding roughly to 35 per cent of the virial radius (≈450 kpc). We fit the X-ray emission with the standard isothermal β model, and it is found that the enclosed gas mass within 160 kpc is $1.15_{-0.24}^{+0.22} \times 10^{11} \, \rm {M}_{\odot }$. Extrapolating the gas mass profile out to the virial radius, the estimated gas mass is $8.25_{-1.77}^{+1.62} \times 10^{11} \, \rm {M}_{\odot }$, which makes up roughly 65 per cent of the total baryon mass content of the galaxy. When the stellar mass is considered and accounting for the statistical and systematic uncertainties, the baryon mass fraction within the virial radius is $0.121_{-0.043}^{+0.043}$, in agreement with the universal baryon fraction. The baryon mass fraction is consistent with all baryons falling within r200, or with only half of the baryons falling within r200. Similar to the massive spiral galaxies NGC 1961 and NGC 6753, we find a low value for the metal abundance of ≈ 0.1 Z⊙, which appears uniform with radius. We also detect diffuse X-ray emission associated with the northern and southern lobes, possibly attributed to inverse Compton scattering of cosmic microwave background photons. The estimated energy densities of the electrons and magnetic field in these radio lobes suggest that they are electron-dominated by a factor of 10−200, depending on the choice of the lower cut-off energy of the electron spectrum.
We show that ocean fronts set recruitment patterns among both community-building invertebrates and commercially important fishes in nearshore intertidal and rocky reef habitats. Chlorophyll ...concentration and recruitment of several species of intertidal invertebrates (Balanus spp., Chthamalus spp., Mytilus spp.) and rockfishes (Sebastes spp.) are positively correlated with front probability along the coast of the California Current Large Marine Ecosystem. Abundances of recent settlers and adults for nearshore rockfish species are also positively correlated with front probability. The interaction of coastal topography and bathymetry sets spatial scales of fronts and consequently recruitment at approximately 50 km during active upwelling, compared to 200 km or greater during non-upwelling periods. Such relationships between fronts and recruitment are likely to be consistent across other marine ecosystems—from coastal waters to the open ocean—and provide a critical link between adults and widely dispersing young. Ocean fronts, already known as features with high biodiversity and resilience in pelagic habitats, also set recruitment and connectivity patterns across multiple taxa for intertidal and rocky reef communities, thus linking biodiversity and resilience in coastal and benthic habitats as well.
At present most knowledge on the impact of iron on
18O / 16O ratios (i.e. δ18O) of dissolved oxygen
(DO) under circum-neutral conditions stems from experiments carried out
under controlled laboratory ...conditions. These showed that iron oxidation
leads to an increase in δ18ODO values. Here we present the
first study on effects of elevated Fe(II) concentrations on the δ18ODO in a natural, iron-rich, circum-neutral watercourse. Our
results show that iron oxidation was the major factor for rising dissolved oxygen
isotope compositions in the first 85 m of the system in the cold season
(February) and for the first 15 m during the warm season (May). Further
along the course of the stream, the δ18ODO decreased
towards values known for atmospheric equilibration around +24.6 ‰ during both seasons. Possible drivers for these changes may be reduced iron oxidation, increased atmospheric exchange and
DO production by oxygenic phototrophic algae mats. In the cold season, the
δ18ODO values stabilized around atmospheric equilibrium,
whereas in the warm season stronger influences by oxygenic photosynthesis caused values down to +21.8 ‰. In the warm season
from 145 m downstream of the spring, the δ18ODO
increased again until it reached atmospheric equilibrium. This trend can be
explained by respiratory consumption of DO combined with a relative
decrease in photosynthetic activity and increasing atmospheric influences.
Our study shows that dissolved Fe(II) can exert strong effects on the
δ18ODO of a natural circum-neutral spring system even
under constant supply of atmospheric O2. However, in the presence of
active photosynthesis, with supply of O2 to the system, direct
effects of Fe oxidation on the δ18ODO value become
masked. Nonetheless, critical Fe(II) concentrations may indirectly control
DO budgets by enhancing photosynthesis, particularly if cyanobacteria are
involved.
For climate models that use paleo-environment data to predict future climate change, tree-ring isotope variations are one important archive for the reconstruction of paleo-hydrological conditions. ...Due to the rather complicated pathway of water, starting from precipitation until its uptake by trees and the final incorporation of its components into tree-ring cellulose, a closer inspection of seasonal variations of tree water uptake is important. In this study, branch and needle samples of two pine species (Pinus pinaster and Pinus nigra subsp. laricio) and several water compartments (precipitation, creek, soil) were sampled over a two-year period and analyzed for the temporal variations of their oxygen and hydrogen stable isotope ratios (δ18O and δ2H) at five sites over an elevation gradient from sea level to around 1600 m a.s.l. on the Mediterranean island of Corsica (France). A new model was established to disentangle temporal relationships of source water uptake of trees. It uses a calculation method that incorporates the two processes mostly expected to affect source water composition: mixing of waters and evaporation. The model results showed that the temporal offset from precipitation to water uptake is not constant and varies with elevation and season. Overall, seasonal source water origin was shown to be dominated by precipitation from autumn and spring. While autumn precipitation was a more important water source for trees growing at mid- (~800–1000 m a.s.l) and high-elevation (~1600 m a.s.l.) sites, trees at coastal sites mostly took up water from late winter and spring. These findings show that predicted decreases in precipitation amounts during the wet season in the Mediterranean can have strong impacts on water availability for pine trees, especially at higher elevations.
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•Problem: Trees access soil water with different ages of filtration•Mixing of successive precipitation samples was used to model source water for trees.•Temporal offset between precipitation and tree water uptake is not constant.•Trees mostly use precipitation from autumn at higher and spring at lower elevations.
Early mortality in multiple myeloma (MM) is usually attributed to combined effects of active disease and comorbid factors. We have studied early deaths in a series of large multicenter trials to ...assess direct causes of death, their predictability, and whether current management strategies have reduced their frequency.
A total of 3,107 newly diagnosed patients entered onto United Kingdom Medical Research Council MM trials from 1980 to 2002 were studied. Trial files, final clinical summaries, and postmortem reports were analyzed.
Death within 60 days of trial entry occurred in 299 patients (10%). Logistic regression modeling identified beta 2-microglobulin, performance status, and age as the most important predictors of early death, but only with 61% sensitivity and 73% specificity. Forty-five percent of deaths were attributable to infection, which was often associated with bone pain (particularly thoracic pain) and delay in presenting to medical care. Neutropenia was present at diagnosis in only 11 of the 135 deaths from infection. Renal failure was present in 28% of early deaths and was linked to light-chain MM, hypercalcemia, dehydration, and nonsteroidal anti-inflammatory drugs. There was no time related reduction in the percentage or nature of early deaths in 1,550 patients older than 65 years receiving similar therapy between 1982 and 2002.
A tenth of patients die within 60 days of diagnosis of MM. Infection and renal failure are the main direct causes of early mortality, which cannot be accurately predicted by presenting prognostic features. All patients should be considered at high risk of death during induction therapy.
The granitic Uhlirska headwater catchment with a size of 1.78km2 is located in the Jizera Mountains in the northern Czech Republic and received among the highest inputs of anthropogenic acid ...depositions in Europe. An analysis of sulphate (SO42–) distribution in deposition, soil water, stream water and groundwater compartments allowed to establish a SO42– mass-balance (deposition input minus surface water export) and helped to evaluate which changes occurred since the last evaluation of the catchment in 1997. The determined SO42– concentrations decreased in the following order: wetland groundwater>groundwater from 20m below ground level (bgl)>groundwater from 30m bgl>stream water>groundwater from10m bgl>hillslope soil water>wetland soil water>bulk deposition with median values of 0.24, 0.21, 0.17, 0.15, 0.11, 0.07, 0.03 and 0.01mmolL−1, respectively. Our results show that average deposition reductions of 62% did not result in equal changes of the sulphate mass-balance, which changed by only 47%. This difference occurs because sulphate originates from internal sources such as the groundwater and soil water. The Uhlirska catchment is subject to delayed recovery from anthropogenic acid depositions and remains a net source of stored sulphur even after three decades of declining inputs. The wetland groundwater and soil water provide environmental memories of legacy pollutant sulphate. Elevated stream water sulphate concentrations after the unusually dry summer 2015 imply importance of weather and climate patterns for future recovery from acidification.
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•The granitic Uhlirska catchment (Czech Republic) in the Black Triangle area was severely impacted by acid rain in the 1980s.•229 samples of soil water, groundwater and stream water were collected.•30years after peak depositions sulphate mass-balance (deposition input minus surface export) was found to be still governed by sulphate from acid rain input.•Wetlands and related groundwater compartments exhibited the largest water sulphate reservoirs for intermediate storage.
A
bstract
We present results of the Relic Axion Dark-Matter Exploratory Setup (RADES), a detector which is part of the CERN Axion Solar Telescope (CAST), searching for axion dark matter in the 34.67
...μ
eV mass range. A radio frequency cavity consisting of 5 sub-cavities coupled by inductive irises took physics data inside the CAST dipole magnet for the first time using this filter-like haloscope geometry. An exclusion limit with a 95% credibility level on the axion-photon coupling constant of g
aγ
≳ 4 × 10
−
13
GeV
−
1
over a mass range of 34
.
6738
μ
eV
< m
a
<
34
.
6771
μ
eV is set. This constitutes a significant improvement over the current strongest limit set by CAST at this mass and is at the same time one of the most sensitive direct searches for an axion dark matter candidate above the mass of 25
μ
eV. The results also demonstrate the feasibility of exploring a wider mass range around the value probed by CAST-RADES in this work using similar coherent resonant cavities.
Hypothetical low-mass particles, such as axions, provide a compelling explanation for the dark matter in the universe. Such particles are expected to emerge abundantly from the hot interior of stars. ...To test this prediction, the CERN Axion Solar Telescope (CAST) uses a 9 T refurbished Large Hadron Collider test magnet directed towards the Sun. In the strong magnetic field, solar axions can be converted to X-ray photons which can be recorded by X-ray detectors. In the 2013-2015 run, thanks to low-background detectors and a new X-ray telescope, the signal-to-noise ratio was increased by about a factor of three. Here, we report the best limit on the axion-photon coupling strength (0.66 × 10-10 GeV-1 at 95% confidence level) set by CAST, which now reaches similar levels to the most restrictive astrophysical bounds.
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