A time dependent relation between EUV solar flare light-curves from lines with differing formation temperatures

Extreme ultraviolet (EUV) solar flare emissions evolve in time as the emitting plasma heats and then cools. Although accurately modeling this evolution has been historically difficult, especially for empirical relationships, it is important for understanding processes at the Sun, as well as for their influence on planetary atmospheres. With a goal to improve empirical flare models, a new simple empirical expression is derived to predict how cool emissions will evolve based on the evolution of a hotter emission. This technique is initially developed by studying 12 flares in detail observed by the EUV Variability Experiment (EVE) onboard the Solar Dynamics Observatory (SDO). Then, over 1100 flares observed by EVE are analyzed to validate these relationships. The Cargill and Enthalpy Based Thermal Evolution of Loops (EBTEL) flare cooling models are used to show that this empirical relationship implies the energy radiated by a population of hotter formed ions is approximately proportional to the energy exciting a population of cooler formed ions emitting when the peak formation temperatures of the two lines are up to 72% of each other and above 2 MK. These results have practical implications for improving flare irradiance empirical modeling and for identifying key emission lines for future monitoring of flares for space weather operations; and also provide insight into the cooling processes of flare plasma.Comment: Final version accepted for publication by the Journal of Space Weather and Space Climate on 23 November 201

Upper limits on the luminosity of the progenitor of type Ia supernova SN2014J

We analysed archival data of Chandra pre-explosion observations of the position of SN2014J in M82. No X-ray source at this position was detected in the data, and we calculated upper limits on the luminosities of the progenitor. These upper limits allow us to firmly rule out an unobscured supersoft X-ray source progenitor with a photospheric radius comparable to the radius of white dwarf near the Chandrasekhar mass (~1.38 M_sun) and mass accretion rate in the interval where stable nuclear burning can occur. However, due to a relatively large hydrogen column density implied by optical observations of the supernova, we cannot exclude a supersoft source with lower temperatures, kT < 80 eV. We find that the supernova is located in the centre of a large structure of soft diffuse emission, about 200 pc across. The mass, ~3x10^4 M_sun and short cooling time of the gas, tau_cool ~ 8 Myrs, suggest that it is a supernova-inflated super-bubble, associated with the region of recent star formation. If SN2014J is indeed located inside the bubble, it likely belongs to the prompt population of type Ia supernovae, with a delay time as short as ~ 50 Myrs. Finally, we analysed the one existing post-supernova Chandra observation and placed upper limit of ~ (1-2) 10^37 erg/s on the X-ray luminosity of the supernova itself.Comment: 8 pages, 6 figure

Determining surface-wave magnitudes from regional Nevada Test Site data

We re-examine the use of surface-wave magnitudes to determine the yield of underground nuclear explosions and the associated magnitude-yield scaling relationship. We have calculated surface-wave magnitudes for 190 Nevada Test Site (NTS) shots using regional long-period seismograms from a combined super-network of 55 North American stations. Great effort went towards making the data set comprehensive and diverse in terms of yield, source location and shot medium in order to determine the portability of surface-wave magnitude scales. In particular, we examine Pahute Mesa, Rainier Mesa and Yucca Flat explosions detonated above and below the water table, and which range over three orders of magnitude in yield. By observation we find a low-yield measure threshold of approximately one kiloton (kt) for (assumedly) moderately well-coupled explosions recorded at near-regional (<500 km) stations, which have little microseismic noise. In order to utilize regional surface waves (Δ < 15°) for quantifying sources and for discrimination purposes, we have developed related methods for determining time-domain surface-wave magnitudes and scalar moments from regional Rayleigh waves. Employing regional surface-wave data lowers the effective magnitude threshold. One technique employs synthetic seismograms to establish a relationship between the amplitude of the regional Airy phase, or Rayleigh pulse of the Rayleigh wavetrain and an associated surface-wave magnitude, based on conventional M_S determinations, calculated from synthetic seismograms propagated to 40°. The other method uses synthetic seismograms in a similar fashion, but the relationship used is a more straightforward one between scalar moment and peak Rayleigh wave amplitude. Path corrections are readily implemented to both methods. The inclusion of path corrections decreases the M_S variance by a factor of two and affects the absolute scaling relationship by up to a factor of 0.1 magnitude units. This latter effect is attributed to the particular station network used and the Green's functions used to obtain the 40° M_S values. Using a generic structure for the distance travelled past the actual source-receiver path minimizes the difference between magnitudes determined with and without path corrections. The method gives stable M_S values that correlate well with other magnitude scale values over a range of three orders of magnitude in source yield. Our M_S values scale very similarly to more standard teleseismic M_S values from other studies, although the absolute MS values vary by ±M0.5 magnitude units about ours. Such differences are due in part to the choice of MS formula used. For purposes of future user comparisons, we give conversion values to the previous studies. Our most refined M_S values give the relationship M_S = 1.00 x log_10 (yield) +B, where B is dependent upon source region and shot medium. This yield exponent of unity holds for events of all sizes and is in line with M_S-yield scaling relations found by other studies. When events are grouped with respect to source region, significantly better fits to these individual-site linear-regression curves are obtained compared to the fits obtained using a single, all-inclusive- model. This observation implies that shot-site parameters and source structure can significantly affect surface-wave-magnitude measurements. We present these M_S values primarily to augment the extensive historical analysis of explosion data based on surface-wave magnitudes by using regional data to increase the number of events with surface-wave magnitudes. These magnitudes are consistant with the teleseismically determined magnitudes of larger events. We present our preferred surface-wave moment values in a sequel paper

Effects of the triaxial deformation and pairing correlation on the proton emitter 145Tm

The ground-state properties of the recent reported proton emitter 145Tm have been studied within the axially or triaxially deformed relativistic mean field (RMF) approaches, in which the pairing correlation is taken into account by the BCS-method with a constant pairing gap. It is found that triaxiality and pairing correlations play important roles in reproducing the experimental one proton separation energy. The single-particle level, the proton emission orbit, the deformation parameters beta = 0.22 and gamma = 28.98 and the corresponding spectroscopic factor for 145Tm in the triaxial RMF calculation are given as well.Comment: 17 pages, 7 figures and 1 table. accepted by Physical Review

Clinical effectiveness and cost effectiveness of individual mental health workers colocated within primary care practices: a systematic literature review

Objectives Mental health disorders contribute significantly to the global burden of disease and lead to extensive strain on health systems. The integration of mental health workers into primary care has been proposed as one possible solution, but evidence of clinical and cost effectiveness of this approach is unclear. We reviewed the clinical and cost effectiveness of mental health workers colocated within primary care practices. Design Systematic literature review. Data sources We searched the Medline, Embase, PsycINFO, Healthcare Management Information Consortium (HMIC) and Global Health databases. Eligibility criteria All quantitative studies published before July 2019 were eligible for the review; participants of any age and gender were included. Studies did not need to report a certain outcome measure or comparator in order to be eligible. Data extraction and synthesis Data were extracted using a standardised table; however, pooled analysis proved unfeasible. Studies were assessed for risk of bias using the Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) tool and the Cochrane collaboration’s tool for assessing risk of bias in randomised trials. Results Fifteen studies from four countries were included. Mental health worker integration was associated with mental health benefits to varied populations, including minority groups and those with comorbid chronic diseases. Furthermore, the interventions were correlated with high patient satisfaction and increases in specialist mental health referrals among minority populations. However, there was insufficient evidence to suggest clinical outcomes were significantly different from usual general practitioner care. Conclusions While there appear to be some benefits associated with mental health worker integration in primary care practices, we found insufficient evidence to conclude that an onsite primary care mental health worker is significantly more clinically or cost effective when compared with usual general practitioner care. There should therefore be an increased emphasis on generating new evidence from clinical trials to better understand the benefits and effectiveness of mental health workers colocated within primary care practices

Analyses of the OSU-MASLWR Experimental Test Facility

Today, considering the sustainability of the nuclear technology in the energy mix policy of developing and developed countries, the international community starts the development of new advanced reactor designs. In this framework, Oregon State University (OSU) has constructed, a system level test facility to examine natural circulation phenomena of importance to multi-application small light water reactor (MASLWR) design, a small modular pressurized water reactor (PWR), relying on natural circulation during both steady-state and transient operation. The target of this paper is to give a review of the main characteristics of the experimental facility, to analyse the main phenomena characterizing the tests already performed, the potential transients that could be investigated in the facility, and to describe the current IAEA International Collaborative Standard Problem that is being hosted at OSU and the experimental data will be collected at the OSU-MASLWR test facility. A summary of the best estimate thermal hydraulic system code analyses, already performed, to analyze the codes capability in predicting the phenomena typical of the MASLWR prototype, thermal hydraulically characterized in the OSU-MASLWR facility, is presented as well

Ten year change in forest succession and composition measured by remote sensing

Vegetation dynamics and changes in ecological patterns were measured by remote sensing over a 10 year period (1973 to 1983) for 148,406 landscape elements, covering more than 500 sq km in a protected forested wilderness. Quantitative measurements were made possible by methods to detect ecologically meaningful landscape units; these allowed measurement of ecological transition frequencies and calculation of expected recurrence times. Measured ecological transition frequencies reveal boreal forest wilderness as spatially heterogeneous and highly dynamic, with one-sixth of the area in clearings and early successional stages, consistent with recent postulates about the spatial and temporal patterns of natural ecosystems. Differences between managed forest areas and a protected wilderness allow assessment of different management regimes

Gravitational radiation from collapsing magnetized dust

In this article we study the influence of magnetic fields on the axial gravitational waves emitted during the collapse of a homogeneous dust sphere. We found that while the energy emitted depends weakly on the initial matter perturbations it has strong dependence on the strength and the distribution of the magnetic field perturbations. The gravitational wave output of such a collapse can be up to an order of magnitude larger or smaller calling for detailed numerical 3D studies of collapsing magnetized configurations