Extended Objects Research Articles

Body Marks of the Past in Toni Morrison’s A Mercy and Home

Toni Morrison’s project of reimagining individual memories of the African American past has been immortalized by the image of the chokecherry tree of scar tissue on Sethe’s back in Beloved. Invisible and dumb for Sethe, the scars have to be faced and interpreted with the help of others in order to process traumatic memories of the slave past. The image questions a presumed opposition between objects of memory as separate from subjects of memory, as the wound, the supposed object is located in the body of the subject, Sethe. Body marks of the past also appear in Morrison’s novels after 2001, which are generally considered sparse compared to her previous texts. Relying on Marianne Hirsch’s method of reading how body marks create a “sense memory” of traumatic experience, the paper explores the webs of meaning invoked by bodily wounds and other extended objects of memory in Morrison’s late novels. The paper claims that although these novels continue to rely on the representation and processing of sense memories, they represent a truncated version compared to earlier novels, in which wounds figure not so much as metaphoric nodes of interaction, but rather as themes.

Scanning Fabry–Perot Interferometer of the 6-m SAO RAS Telescope

The scanning Fabry-Perot interferometer (FPI) - is the oldest method of optical 3D spectroscopy. It is still in use because of the high spectral resolution it provides over a large field of view. The history of the application of this method for the study of extended ob jects (nebulae and galaxies) and the technique of data reduction and analysis are discussed. The paper focuses on the performing observations with the scanning FPI on the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS). The instrument is currently used as a part of the SCORPIO-2 multimode focal reducer. The results of studies of various galactic and extragalactic objects with the scanning FPI on the 6-m telescope - star-forming regions and young stellar objects, spiral, ring, dwarf and interacting galaxies, ionization cones of active galactic nuclei, galactic winds, etc. are briefly discussed. Further prospects for research with the scanning FPI of the SAO RAS are discussed.

D^{±}D^{*∓} Hadronic Atom as a Key to Revealing the X(3872) Mystery.

The X(3872), whose mass coincides with the D^{0}D[over ¯]^{*0} threshold, is the most extended hadron object. Since its discovery in 2003, debates have never stopped regarding its internal structure. We propose a new object, the X atom, which is the D^{±}D^{*∓} composite system with positive charge parity and a mass of (3879.89±0.07) MeV, formed mainly due to the Coulomb force. We show that a null signal of the X atom can be used to put a lower limit on the binding energy of the X(3872). From the current knowledge of the X(3872) properties, the production rate for the X atom relative to the X(3872) in B decays and at hadron colliders should be at least 1×10^{-3}. New insights into the X(3872) will be obtained through studying the X atom.

ALMA discovery of a dual dense probably rotating outflow from a massive young stellar object G18.88MME

ABSTRACT We report the discovery of a very dense jet-like fast molecular outflow surrounded by a wide-angle wind in a massive young stellar object (MYSO) G18.88MME (stellar mass ∼8 M⊙) powering an extended green object G18.89−0.47. Four cores MM1–4 are identified in the Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm continuum map (resolution ${\sim} 0.8\, \mathrm { arcsec}$) towards G18.88MME, and are seen at the centre of the emission structure (extent ∼0.3 pc × 0.2 pc) detected in the ALMA map. G18.88MME is embedded in the core MM1 (mass ∼13–18 M⊙), where no radio continuum emission is detected. The molecular outflow centred at MM1 is investigated in the SiO(5–4), HC3N(24–23) and 13CO(2–1) lines. The detection of HC3N in the outflow is rare in MYSOs and indicates its very high density. The position–velocity diagrams display a fast narrow outflow (extent ∼28 000 AU) and a slower wide-angle more extended outflow towards MM1, and both of these components show a transverse velocity gradient indicative of a possible rotation. All these observed features together make G18.88MME as a unique object for studying the unification of the jet-driven and wind-driven scenarios of molecular outflows in MYSOs.

Phase-contrast imaging of multiply-scattering extended objects at atomic resolution by reconstruction of the scattering matrix

Three-dimensional phase contrast imaging of multiply-scattering samples in X-ray and electron microscopy is extremely challenging, due to small numerical apertures, the unavailability of wavefront shaping optics, and the highly nonlinear inversion required from intensity-only measurements. In this work, we present a new algorithm using the scattering matrix formalism to solve the scattering from a non-crystalline medium from scanning diffraction measurements, and recover the illumination aberrations. Our method will enable 3D imaging and materials characterization at high resolution for a wide range of materials.

Unified model beyond grand unification

Strong, electromagnetic, and weak forces were unified in the Standard Model (SM) with spontaneous gauge symmetry breaking. These forces were further conjectured to be unified in a simple Lie group gauge interaction in the Grand Unification (GUT). In this work, we propose a theory beyond the SM and GUT by adding new gapped Topological Phase Sectors consistent with the nonperturbative global anomaly cancellation and cobordism constraints (especially from the baryon minus lepton number ${\bf B}-{\bf L}$, the electroweak hypercharge $Y$, and the mixed gauge-gravitational anomaly). Gapped Topological Phase Sectors are constructed via symmetry extension, whose low energy contains unitary Lorentz invariant topological quantum field theories (TQFTs): either 3+1d non-invertible TQFT, or 4+1d invertible or non-invertible TQFT (short-range or long-range entangled gapped phase). Alternatively, there could also be right-handed "sterile" neutrinos, gapless unparticle physics, more general interacting conformal field theories, or gravity with topological cobordism constraints, or their combinations to altogether cancel the mixed gauge-gravitational anomaly. We propose that a new high-energy physics frontier beyond the conventional 0d particle physics relies on the new Topological Force and Topological Matter including gapped extended objects (gapped 1d line and 2d surface operators or defects, etc., whose open ends carry deconfined fractionalized particle or anyonic string excitations) or gapless conformal matter. Physical characterizations of these gapped extended objects require the mathematical theories of cohomology, cobordism, or category. Although weaker than the weak force, Topological Force is infinite-range or long-range which does not decay in the distance, and mediates between the linked worldvolume trajectories via fractional or categorical statistical interactions.

Geometric Justification of the Fundamental Interaction Fields for the Classical Long-Range Forces

Based on the principle of reparametrization invariance, the general structure of physically relevant classical matter systems is illuminated within the Lagrangian framework. In a straightforward way, the matter Lagrangian contains background interaction fields, such as a 1-form field analogous to the electromagnetic vector potential and symmetric tensor for gravity. The geometric justification of the interaction field Lagrangians for the electromagnetic and gravitational interactions are emphasized. The generalization to E-dimensional extended objects (p-branes) embedded in a bulk space M is also discussed within the light of some familiar examples. The concept of fictitious accelerations due to un-proper time parametrization is introduced, and its implications are discussed. The framework naturally suggests new classical interaction fields beyond electromagnetism and gravity. The simplest model with such fields is analyzed and its relevance to dark matter and dark energy phenomena on large/cosmological scales is inferred. Unusual pathological behavior in the Newtonian limit is suggested to be a precursor of quantum effects and of inflation-like processes at microscopic scales.

Track-before-detect for complex extended targets based sequential monte carlo Mb-sub-random matrices filter

Tracking for multiple extended objects with a complex extension is a challenging radar technology; especially for small back-scattering objects such as extended stealth targets (ESTs). This work provides a new approach for ESTs tracking under the non-linear dynamic system based on track-before-detect (TBD) approach. The sequential Monte Carlo multi-Bernoulli (SMC-MB) filter provides a good framework to cope with TBD approach. Recently, the SMC-MB filter with a random matrix model (RMM) has been applied for tracking extended targets by additional state variables. However, SMC-MB-RMM filter is implemented with known detection probability, which is unsuitable for ESTs-TBD scenario. Therefore, we introduce a new SMC-MB-RMM filter hybrid with TBD algorithm, which is effective method to track ESTs. In ESTs-RMM-TBD scenarios, although the extension ellipsoid is effective, it may not be accurate enough due to lacking the useful parameters, such as shape, size and orientation. Therefore, we propose a ESTs-Sub-RMM-TBD composed of sub-ellipses; each one is applied by RMM. Based on such models, a SMC-Sub-RMM-MB-TBD algorithm is applied to estimate extensions and kinematic states for each sub-objects. The simulation results show that the presented filter has a small OSPA errors and more accurate cardinality calculation than the other algorithms.

Optical follow-up observation for GW event S190510g using Subaru/Hyper Suprime-Cam

Abstract A gravitational wave event, S190510g, which was classified as a binary-neutron-star coalescence at the time of preliminary alert, was detected by LIGO/Virgo collaboration on 2019 May 10. At 1.7 hours after the issue of its preliminary alert, we started a target-of-opportunity imaging observation in the Y band to search for its optical counterpart using the Hyper Suprime-Cam (HSC) on the Subaru Telescope. The observation covers a 118.8 deg2 sky area corresponding to $11.6\%$ confidence in the localization skymap released in the preliminary alert and $1.2\%$ in the updated skymap. We divided the observed area into two fields based on the availability of HSC reference images. For the fields with the HSC reference images, we applied an image subtraction technique; for the fields without the HSC reference images, we sought individual HSC images by matching a catalog of observed objects with the PS1 catalog. The search depth is 22.28 mag in the former method and the limit of search depth is 21.3 mag in the latter method. Subsequently, we performed visual inspection and obtained 83 candidates using the former method and 50 candidates using the latter method. Since we only have the one-day photometric data, we evaluated the probability of candidates being located inside the 3D skymap by estimating their distances with photometry of associated extended objects. We found three candidates are likely located inside the 3D skymap and concluded they could be a counterpart of S190510g, while most of the 133 candidates were likely to be supernovae because the number density of candidates was consistent with the expected number of supernova detections. By comparing our observational depth with a light-curve model of such a kilonova reproducing AT2017gfo, we show that early deep observations with the Subaru/HSC can capture the rising phase of the blue component of a kilonova at the estimated distance of S190510g (∼230 Mpc).

The VVV near-IR galaxy catalogue beyond the Galactic disc

ABSTRACT Knowledge about the large-scale distribution of galaxies is far from complete in the Zone of Avoidance (ZoA), which is mostly due to high interstellar extinction and to source confusion at lower Galactic latitudes. Past near-infrared (NIR) surveys, such as the Two Micron All Sky Survey (2MASS), have shown the power of probing large-scale structure at these latitudes. Our aim is to map the galaxy distribution across the Southern Galactic plane using the VISTA Variables in the Vía Láctea Survey (VVV), which reach 2–4 mag deeper than 2MASS. We used SExtractor+PSFEx to identify extended objects and to measure their sizes, the light concentration index, magnitudes, and colours. Morphological and colour constraints and visual inspection were used to confirm galaxies. We present the resulting VVV NIR Galaxy Catalogue (VVV NIRGC) of 5563 visually confirmed galaxies, of which only 45 were previously known. This is the largest catalogue of galaxies towards the Galactic plane, with 99 per cent of these galaxies being new discoveries. We found that the galaxy density distribution closely resembled the distribution of low interstellar extinction of the existing NIR maps. We also present a description of the 185 2MASS extended sources observed in the region, of which 16 per cent of these objects had no previous description, which we have now classified. We conclude that interstellar extinction and stellar density are the main limitations for the detection of background galaxies in the ZoA. The VVV NIRGC is a new data set providing information for extragalactic studies in the Galactic plane.

Scalable Detection and Tracking of Geometric Extended Objects

Multiobject tracking provides situational awareness that enables new applications for modern convenience, public safety, and homeland security. This paper presents a factor graph formulation and a particle-based sum-product algorithm (SPA) for scalable detection and tracking of extended objects. The proposed method dynamically introduces states of newly detected objects, efficiently performs probabilistic multiple-measurement to object association, and jointly infers the geometric shapes of objects. Scalable extended object tracking (EOT) is enabled by modeling association uncertainty by measurement-oriented association variables and newly detected objects by a Poisson birth process. Contrary to conventional EOT methods, a fully particle-based approach makes it possible to describe different geometric object shapes. The proposed method can reliably detect, localize, and track a large number of closely-spaced extended objects without gating and clustering of measurements. We demonstrate significant performance advantages of our approach compared to the recently introduced Poisson multi-Bernoulli mixture filter. In particular, we consider a simulated scenarios with up to twenty closely-spaced objects and a real autonomous driving application where measurements are captured by a lidar sensor.

Variational Measurement Update for Extended Object Tracking Using Gaussian Processes

We present an alternative inference framework for the Gaussian process-based extended object tracking (GPEOT) models. The method provides an approximate solution to the Bayesian filtering problem in GPEOT by relying on a new measurement update, which we derive using variational Bayes techniques. The resulting algorithm effectively computes approximate posterior densities of the kinematic and the extent states. We conduct various experiments on simulated and real data and examine the performance compared with a reference method, which employs an extended Kalman filter for inference. The proposed algorithm significantly improves the accuracy of both the kinematic and the extent estimates and proves robust against model uncertainties.

Genetic gain in grain yield and oil content of Noug (Guizotia abyssinica) in Ethiopia

The primary and extended objective of plant breeding is to advance productivity to match the lengthening food requirements of people. Estimation of genetic advance from a breeding program and periodic evaluation of improvement in the genetic gain of a crop through released varieties is therefore needed to perceive changes and success generated by breeding activities. Periodic valuation of genetic progress of crop varieties is required to perceive the effectiveness of past breeding activities in genetic yield potential and prompt future selection criteria to aid further improvement. A total of 5 varieties have been released in Ethiopia, from 1988 to 2010. However, the level of genetic progress was not quantified. This study aimed to assess the genetic gain in seed yield potential and oil content of Noug (Guizotia abyssinica) and estimate changes made to yield related traits by genetic improvement of the crop. The experiment was conducted using 5 noug improved varieties and one local variety arranged in RCBD with four replications in 2016/17 main cropping season under rainfed condition. Results indicated that seed yield increased significantly during these 22 years. The estimated annual yield gain was 10.36 kg ha-1 year–1(1.58% per year), reflecting the important efforts of the past breeding programs. Number of head per plant, number of seed per head, Seed yield per plant, biomass yield, harvest and oil content were also increased significantly by 1.72%, 1.71%, 1.85%, 0.33%, 1.03% and 0.34% per year, respectively. The endeavor should be encouraged and extended to accomplish more advances in these and other relevant traits. Noug breeding has not ascertained plateau in Ethiopia. Thus, development of higher yielding varieties of noug should persist to lengthen Noug grain yields if past tendency intends the prospective. To see the impact of the accomplishment in the genetic advance of noug research, it is compulsory to covenant huge scale popularization of the released varieties.

Acoustical and Perceptual Analysis of Noise Reduction Strategies in Individuals With Auditory Neuropathy Spectrum Disorders.

Purpose The conventional amplification devices render minimal or no benefit at abating the speech perception problems of individuals with auditory neuropathy spectrum disorder (ANSD). This study was undertaken to evaluate the effect of noise reduction strategies (multiband spectral subtraction, Wiener-as, Karhunen-Loeve transform [Subspace], and ideal binary mask [IdBM] algorithm) on speech using speech perception measures and acoustic measure among individuals with ANSD. Method Two groups of participants (age: 17-43 years) were recruited in the study. Group I comprised 12 individuals with a confirmed diagnosis of ANSD and not exceeding moderate degree of hearing loss and Group II of 10 individuals with normal hearing in both ears. The signal-to-noise required for 50% speech recognition (SNR-50) was measured for the participants in five conditions, that is, unprocessed speech and speech processed with four noise reduction strategies. Additionally, an acoustic objective measure Extended Short-Time Objective Intelligibility algorithm was employed to estimate the intelligibility index across the conditions. Results Significant difference was found across conditions in both the groups. Pairwise comparison revealed significantly better speech perception on SNR-50 measure with IdBM strategy, for both the groups. No significant difference in SNR-50 was observed with other noise reduction strategies. IdBM condition also gave the highest intelligibility index (d) values using Extended Short-Time Objective Intelligibility algorithm. This finding needs to be verified on a larger group of individuals with ANSD. Conclusions IdBM noise reduction strategy rendered significantly lower SNR-50 compared to other noise reduction strategies for individuals with ANSD in this study. This provides clinical evidence for the same and also recommends trying on a larger group of participants before its implementation in hearing devices. Apart from this, the current strategies used in hearing aids provide no improvement in speech identification in noise for this population. Hence, though the present hearing aids may show benefit in quiet condition, chances of its rejection are high in noisy backgrounds.

Extended Object Tracking Using Spatially Resolved Micro-Doppler Signatures

Recent progress in radar development enable high-resolution radar sensors to resolve multiple detections for an extended object. One of the main challenges in radar-based object detection and tracking is the handling of an uncertain measurement model problem dealing with wandering dominant scatter points on the extended object surface depending on the relative orientation and motion. This phenomenon needs to be considered for near extended object tracking in critical driving situations, e.g., for safety applications, which require fast and accurate target state estimation in high dynamic scenarios. This paper presents a method to detect rotating wheels of approaching targets. Using the position and velocity of detected wheels as input for a tracking procedure, instead of target detections, relaxes the uncertain measurement model problem. A generic radar signal processing method to detect the position and bulk velocities of rotating wheels for approaching target vehicles is presented. The method evaluates the micro-Doppler signals, generated by rotating wheels, of close targets. These wheel hypotheses serve as input for a subsequent sequential Monte Carlo tracking framework. The presented methods are evaluated on real experimental data where a target vehicle is used to reconstruct safety-critical dynamic evading maneuvers.

Continuous spontaneous localization reduction rate for rigid bodies

The authors present a detailed assessment of continuous spontaneous localization (one of the best-known models for spontaneous wave-function collapse) collapse and diffusion rates for the center-of-mass motion of rigid extended objects of simple geometry, and discuss in particular corrections arising from the lattice structure of crystalline solids. Among other things, they find that the collapse rate depends on the difference of the mass distributions of the two states onto which the rate is evaluated, i.e., the states onto which the superposition state can collapse.

Reasoning about Cardinal Directions between 3-Dimensional Extended Objects using Answer Set Programming

AbstractWe propose a novel formal framework (called 3D-NCDC-ASP) to represent and reason about cardinal directions between extended objects in 3-dimensional (3D) space, using Answer Set Programming (ASP). 3D-NCDC-ASP extends Cardinal Directional Calculus (CDC) with a new type of default constraints, andNCDC-ASP to 3D. 3D-NCDC-ASP provides a flexible platform offering different types of reasoning: Nonmonotonic reasoning with defaults, checking consistency of a set of constraints on 3D cardinal directions between objects, explaining inconsistencies, and inferring missing CDC relations. We prove the soundness of 3D-NCDC-ASP, and illustrate its usefulness with applications.

Predicate model of process knowledge when detecting and recognizing extended objects such as clouds, angel-echoes in surveillance radars

A predicate model of the process knowledge of inter-period processing of radar signals in the detection and recognition of extended objects and a decision-making method based on precedents have been developed. The main features and structural elements of the process knowledge model are presented. It is shown that the advantages of this model are related to the configuration and hierarchical representation of the process for studying the possible structures of single or groups of impulse signals within the same radar field of view based on the intelligent analysis of signals using the algebra of finite predicates. It is shown how this approach can be used to automate the process of detecting and recognizing extended objects such as clouds, atmospheric inhomogeneities of the angel-echo type. A method for processing process knowledge has been developed as a tool for creating universal algorithms for inter-period processing of signal information to ensure effective detection and recognition of various extended objects, including atmospheric inhomogeneities of the angel-echo type, by accumulating both signal (energy) and logical information in the analyzed cell and in its vicinity. The developed technology includes procedures for formalizing and analyzing the symbolic model of observed objects for making decisions based on precedents. Depending on the types of connections used in the model, classifying and functional networks are distinguished, where some elements of logical and network models are used. The idea of inference rules or decision rules is borrowed from logical models, and the description of knowledge in the form of a semantic neural network is borrowed from network models. In this combined model, procedural information is clearly highlighted. Instead of a logical conclusion, a conclusion or a decisive rule on knowledge appears. As a result of solving the system of predicate equations of process knowledge, we find the place, geometric dimensions and type of the symbolic model of an extended object.

Joint detection, tracking and classification of multiple extended objects based on the JDTC-GIW-MeMBer filter

In this paper, the problem of joint detection, tracking and classification (JDTC) of multiple extended objects (EOs) is addressed using the random finite set (RFS) theory. In the proposed method, the shape of an EO is restricted to an ellipse that can be easily modelled by a random matrix. The classification of an EO is estimated on the basis of size information with respect to its extended part. Furthermore, the extended object RFS is proposed to be modelled as a multi-Bernoulli (MeMBer) process, then the MeMBer filter is naturally adopted to propagate the EO posteriors. In this paper, in order to achieve the closed-form solution, we model the spatial probability density function (SPDF) of each Bernoulli component as the mixture Gaussian inverse Wishart (GIW) process for the JDTC problem. Compared to the existing JDTC strategies, the proposed algorithm, named as JDTC-GIW-MeMBer filter, is demonstrated via simulations to achieve better performance to the existing algorithms on detection and tracking of the EO centers, the estimation accuracy of the extended states, and EO classifications.

Multiwavelength investigation of extended green object G19.88-0.53: revealing a protocluster

ABSTRACT A multiwavelength analysis of star formation associated with the extended green object, G19.88-0.53 is presented in this paper. With multiple detected radio and millimetre components, G19.88-0.53 unveils as harbouring a protocluster rather than a single massive young stellar object. We detect an ionized thermal jet using the upgraded Giant Meterwave Radio Telescope, India, which is found to be associated with a massive, dense and hot ALMA 2.7 mm core driving a bipolar CO outflow. Near-infrared spectroscopy with UKIRT–UIST shows the presence of multiple shock-excited H2 lines concurrent with the nature of this region. Detailed investigation of the gas kinematics using ALMA data reveals G19.88-0.53 as an active protocluster with high-mass star-forming components spanning a wide evolutionary spectrum from hot cores in accretion phase to cores driving multiple outflows to possible UCH ii regions.