Isolating the chiral magnetic effect from backgrounds by pair invariant mass

Topological gluon configurations in quantum chromodynamics induce quark chirality imbalance in local domains, which can result in the chiral magnetic effect (CME)--an electric charge separation along a strong magnetic field. Experimental searches for the CME in relativistic heavy ion collisions via the charge-dependent azimuthal correlator ($\Delta\gamma$) suffer from large backgrounds arising from particle correlations (e.g. due to resonance decays) coupled with the elliptic anisotropy. We propose differential measurements of the $\Delta\gamma$ as a function of the pair invariant mass ($m_{\rm inv}$), by restricting to high $m_{\rm inv}$ thus relatively background free, and by studying the $m_{\rm inv}$ dependence to separate the possible CME signal from backgrounds. We demonstrate by model studies the feasibility and effectiveness of such measurements for the CME search.Comment: 16 preprint pages 5 figures. v2: added a test with a broad "instanton/sphaleron" peak, and added clarifying texts; v3: added event-shape engineering (and two new figures) and expanded discussions on the low invariant mass region; v4: repeated cautionary discussions in introduction and conclusion sections, published versio

Mining Site Reclamation Planning Based on Land Suitability Analysis and Ecosystem Services Evaluation: A Case Study in Liaoning Province, China

Restoration of the degraded ecosystem is a global priority for achieving sustainable development. Although increasing ecosystem service is an important goal of ecological restoration, it is rarely used to inform mine reclamation. This study proposed a reclamation strategy that incorporated land suitability analysis and ecosystem service evaluation for a mining site in Liaoning Province, China. We assessed the land suitability for three reclamation alternatives and identified suitable land uses for each location by comparing their suitability levels. For areas that were suitable for multiple land uses with the same suitability level, the future land uses cannot be identified by land suitability analysis alone, and we employed ecosystem services evaluation to determine the optimal reclamation strategy. The results showed that forest could be restored throughout the entire mining site, agricultural land were most suitable in the western and southern parts, and developed land were in northern parts that were closer to roads and city centers. Our study showed that a large mining site can be reclaimed to different land uses and provided a practical framework for integrating ecosystem services into mine reclamation

SSP-REGULARIZER: A STAR SHAPE PRIOR BASED REGULARIZER FOR VESSEL LUMEN SEGMENTATION IN OCT IMAGES

Optical coherence tomography (OCT) is widely used in high resolution imaging of biological tissues, which can help diagnose coronary heart disease by segmenting the vessellumen at the pixel-level. However, the lumen shape geometry is not well used in the state-of-the-art techniques for OCT image segmentation, especially the data-driven methods, leaving much room for performance improvement if some geometric features could be exploited to provide prior information. Thanks to the star shape geometry of vessel lumen, in this paper, a new Star Shape Prior based Regularizer (SSP-Regularizer) is proposed to improve segmentation performance. To validate its effectiveness, the proposed SSPRegularizer is applied to improve the optimization scheme used in Mask-RCNN for vessel lumen segmentation. Experimental results show that superior performance is achievedwith SSP-Regularizer, indicating its potentials in OCT imagery and optimization schemes