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Recently, a new excited baryon state, $Ω(2012)$, was observed in the invariant mass spectra of $K^-Ξ^0$ and $K^0_S Ξ^-$ by the Belle Collaboration. This state has a narrow width ($\sim 6$ MeV) compared to other baryon states with a similar mass. In this paper, we provide a mini-review on the $Ω(2012)$ state from the molecular perspective, where it appears to be a dynamically generated state with spin-parity $3/2^-$ from the coupled-channels interactions of the $\bar{K} Ξ(1530)$ and $ηΩ$ in $s$-wave and $\bar{K} Ξ$ in $d$-wave. Additionally, alternative explanations for the $Ω(2012)$ resonance are also discussed.
Asteroid 2012 TC4 is a small ($\sim$10 m) near-Earth object that was observed during its Earth close approaches in 2012 and 2017. Earlier analyses of light curves revealed its excited rotation state. We collected all available photometric data from the two apparitions to reconstruct its rotation state and convex shape model. We show that light curves from 2012 and 2017 cannot be fitted with a single set of model parameters -- the rotation and precession periods are significantly different for these two data sets and they must have changed between or during the two apparitions. Nevertheless, we could fit all light curves with a dynamically self-consistent model assuming that the spin states of 2012 TC4 in 2012 and 2017 were different. To interpret our results, we developed a numerical model of its spin evolution in which we included two potentially relevant perturbations: (i) gravitational torque due to the Sun and Earth, and (ii) radiation torque known as the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. Despite our model simplicity, we found that the role of gravitational torques is negligible. Instead, we argue that the observed change of its spin state may be plausibly ex
We perform the flavour $SU(3)$ analysis of the recently discovered $Ω(2012)$ hyperon. We find that well known (four star) $Δ(1700)$ resonance with quantum numbers of $J^P=3/2^-$ is a good candidate for the decuplet partner of $Ω(2012)$ if the branching for the three-body decays of the latter is not too large $\le 70$\%. That implies that the quantum numbers of $Ω(2012)$ are $I(J^P)=0(3/2^-)$. The predictions for the properties of still missing $Σ$ and $Ξ$ decuplet members are made. We also discuss the implications of the ${ \overline{ K} Ξ(1530)}$ molecular picture of $Ω(2012)$. Crucial experimental tests to distinguish various pictures of $Ω(2012)$ are suggested.
In this work we characterize the recently discovered active main belt object P/2012 F5 (Gibbs), which was discovered with a dust trail > 7' in length in the outer main belt, 7 months prior to aphelion. We use optical imaging obtained on UT 2012 March 27 to analyze the central condensation and the long trail. We find nuclear B-band and R-band apparent magnitudes of 20.96 and 19.93 mag, respectively, which give an upper limit on the radius of the nucleus of 2.1 km. The geometric cross-section of material in the trail was ~ 4 x 10^8 m^2, corresponding to a dust mass of ~ 5 x 10^7 kg. Analysis of infrared images taken by the Wide-Field Infrared Survey Explorer in September 2010 reveals that the object was below the detection limit, suggesting that it was less active than it was during 2012, or possibly inactive, just 6 months after it passed through perihelion. We set a 1-sigma upper limit on its radius during this time of 2.9 km. P/2012 F5 (Gibbs) is dynamically stable in the outer main belt on timescales of ~ 1 Gyr, pointing towards an asteroidal origin. We find that the morphology of the ejected dust is consistent with it being produced by a single event that occurred on UT 2011
We present results of a forecast initiated following assimilation of observations for week Week 50 (i.e. the forecast begins December 16, 2012) of the 2012-2013 influenza season for municipalities in the United States. The forecast was made on December 21, 2012. Results from forecasts initiated the three previous weeks (Weeks 47-49) are also presented. Also results from forecasts generated with an SIRS model without absolute humidity forcing (no AH) are shown.
Compilation of CTA contributions to the proceedings of the 2012 Heidelberg Symposium on High Energy Gamma-Ray Astronomy (Gamma 2012), which took place in July 9-13, 2012, in Heidelberg, Germany
This document is part of a series of near real-time weekly influenza forecasts made during the 2012-2013 influenza season. Here we present results of a forecast initiated following assimilation of observations for Week 51 (i.e. the forecast begins December 23, 2012) for municipalities in the United States. The forecast was made on December 28, 2012. Results from forecasts initiated the four previous weeks (Weeks 47-50) are also presented. Predictions generated with an alternate SIRS model, run without absolute humidity forcing (no AH), are also presented.
We present results of a forecast initiated Week 49 (beginning December 9, 2012) of the 2012-2013 influenza season for municipalities in the United States. The forecast was made on December 14, 2012. Results from forecasts initiated the two previous weeks (Weeks 47 and 48) are also presented. Also results from the forecast generated with the SIRS model without AH forcing (no AH) are shown
Recent droughts in the midwestern United States threaten to cause global catastrophe driven by a speculator amplified food price bubble. Here we show the effect of speculators on food prices using a validated quantitative model that accurately describes historical food prices. During the last six years, high and fluctuating food prices have lead to widespread hunger and social unrest. While a relative dip in food prices occurred during the spring of 2012, a massive drought in the American Midwest in June and July threatens to trigger another crisis. In a previous paper, we constructed a model that quantitatively agreed with food prices and demonstrated that, while the behavior could not be explained by supply and demand economics, it could be parsimoniously and accurately described by a model which included both the conversion of corn into ethanol and speculator trend following. An update to the original paper in February 2012 demonstrated that the model previously published was predictive of the ongoing price dynamics, and anticipated a new food crisis by the end of 2012 if adequate policy actions were not implemented. Here we provide a second update, evaluating the effects of the
This paper summarizes the discussions, presentations, and activity of the Future Light Sources Workshop 2012 (FLS 2012) working group dedicated to Electron Sources. The focus of the working group was to discuss concepts and technologies that might enable much higher peak and average brightness from electron beam sources. Furthermore the working group was asked to consider methods to greatly improve the robustness of operation and lower the costs of providing electrons.
We have observed at high resolution spectroscopic changes in Hydrogen Chloride (HCl) and Hydrogen Fluoride (HF) atmospheric trace gases from the 1970s through 2012. HCl rose in strength through 1998 and then decreased to 2012. HF has shown a continual increase to date. Both results are in general agreement with observations from the Jungfraujoch in the Swiss alps.
In March 2010 the Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope discovered for the first time >100 MeV gamma-ray emission from a nova within our galaxy, V407 Cyg. The high-energy spectrum and light curve was explained as a consequence of shock acceleration in the nova shell as it interacts with the local ambient medium. It was suspected that the necessary conditions for high-energy emission from novae would be rare. In June 2012 the LAT detected a new flaring source, Fermi J1750-3243, that is spatially coincident and contemporaneous with a new nova, Nova Sco 2012. We report on the exciting discovery of this new 'gamma-ray' nova and present a detailed analysis of its high-energy properties.
The AgreementMaker system was the leading system in the anatomy task of the Ontology Alignment Evaluation Initiative (OAEI) competition in 2011. While AgreementMaker did not compete in OAEI 2012, here we report on its performance in the 2012 anatomy task, using the same configurations of AgreementMaker submitted to OAEI 2011. Additionally, we also test AgreementMaker using an updated version of the UBERON ontology as a mediating ontology, and otherwise identical configurations. AgreementMaker achieved an F-measure of 91.8% with the 2011 configurations, and an F-measure of 92.2% with the updated UBERON ontology. Thus, AgreementMaker would have been the second best system had it competed in the anatomy task of OAEI 2012, and only 0.1% below the F-measure of the best system.
In over forty presentations on experiments at the 2012 conference on Flavor Physics and CP Violation (FPCP 2012), there was an abundance of beautiful and significant results. This summary of these experiment presentations begins with a reminder of the context in which the measurements have been made and the motivations for making the specific measurements reported at the symposium. Given the number and breadth of physics topics covered at the meeting, this review covers only a limited set of highlights, sort of a traveler's set of souvenir postcards of favorite slides. The selected slides are grouped into eight overlapping categories as an aid to flipping through the postcards and being reminded of the high points of the conference. Finally, there are some summarizing comments about how the experiment results presented here compare to expectations and what we may hope for the future.
After the 2007/2008 financial crisis, the UK government decided that a change in regulation was required to amend the poor control of financial markets. The Financial Services Act 2012 was developed as a result in order to give more control and authority to the regulators of financial markets. Thus, the Financial Conduct Authority (FCA) succeeded the Financial Services Authority (FSA). An area requiring an improvement in regulation was insider trading. Our study examines the effectiveness of the FCA in its duty of regulating insider trading through utilising the event study methodology to assess abnormal returns in the run-up to the first announcement of mergers. Samples of abnormal returns are examined on periods, under regulation either by the FSA or by the FCA. Practically, stock price data on the London Stock Exchange from 2008-2012 and 2015-2019 is investigated. The results from this study determine that abnormal returns are reduced after the implementation of the Financial Services Act 2012; prices are also found to be noisier in the period before the 2012 Act. Insignificant abnormal returns are found in the run-up to the first announcement of mergers in the 2015-2019 period.
These proceedings include papers presented at the Workshop on "The experience of and advances in developing dependable systems in Event-B" held on November 13, 2012 as part of the ICFEM 2012 (Kyoto, Japan).
The contribution contains the preface to the Proceedings to the 15 th Workshop What Comes Beyond the Standard Models, Bled, July 9 - 19, 2012, published in Bled workshops in physics, Vol.13, No. 2, DMFA-Zaloznistvo, Ljubljana, Dec. 2012, and links to the published contributions.
Increases in global food prices have led to widespread hunger and social unrest---and an imperative to understand their causes. In a previous paper published in September 2011, we constructed for the first time a dynamic model that quantitatively agreed with food prices. Specifically, the model fit the FAO Food Price Index time series from January 2004 to March 2011, inclusive. The results showed that the dominant causes of price increases during this period were investor speculation and ethanol conversion. The model included investor trend following as well as shifting between commodities, equities and bonds to take advantage of increased expected returns. Here, we extend the food prices model to January 2012, without modifying the model but simply continuing its dynamics. The agreement is still precise, validating both the descriptive and predictive abilities of the analysis. Policy actions are needed to avoid a third speculative bubble that would cause prices to rise above recent peaks by the end of 2012.
Data mining is one of the most important steps of the knowledge discovery in databases process and is considered as significant subfield in knowledge management. Research in data mining continues growing in business and in learning organization over coming decades. This review paper explores the applications of data mining techniques which have been developed to support knowledge management process. The journal articles indexed in ScienceDirect Database from 2007 to 2012 are analyzed and classified. The discussion on the findings is divided into 4 topics: (i) knowledge resource; (ii) knowledge types and/or knowledge datasets; (iii) data mining tasks; and (iv) data mining techniques and applications used in knowledge management. The article first briefly describes the definition of data mining and data mining functionality. Then the knowledge management rationale and major knowledge management tools integrated in knowledge management cycle are described. Finally, the applications of data mining techniques in the process of knowledge management are summarized and discussed.
This is a status report of the WHIZARD Monte Carlo multi-purpose event generator given at the LCFORUM 2012 at DESY. I review here the development of the WHIZARD generator version 2 with a special emphasis on linear collider physics. In case you use the program, please do cite the official reference(s).