scholarly journals Reliably estimating the statistical significance of a new physics signal by exploiting GPUs

2021 ◽  
Author(s):  
Alexis Pompili ◽  
Adriano Di Florio
Keyword(s):  
Statistical Significance ◽  
New Physics ◽  
Physics Signal

scholarly journals PHYSICS WITH COSMIC NEUTRINOS, PEV TO ZEV

2003 ◽  
Vol 18 (22) ◽  
pp. 4065-4083 ◽  
Author(s):  
THOMAS J. WEILER
Keyword(s):  
Cross Section ◽  
Particle Physics ◽  
Statistical Significance ◽  
Cosmic Ray ◽  
New Physics ◽  
Microwave Background ◽  
Radiation Fields ◽  
Cosmic Neutrino ◽  
Long Lifetime ◽  
The Impact

Neutrinos offer a particularly promising eye on the extreme Universe. Neutrinos are not attenuated by intervening radiation fields such as the Cosmic Microwave Background, and so they are messengers from the very distant and very young phase of the universe. Also, neutrinos are not deflected by cosmic magnetic fields, and so they should point to their sources. In addition, there are particle physics aspects of neutrinos which can be tested only with cosmic neutrino beams. After a brief overview of highest-energy cosmic ray data, and the present and proposed experiments which will perform neutrino astronomy, we discuss two particle physics aspects of neutrinos. They are possible long-lifetime decay of the neutrino, and a measurement of the neutrino-nucleon cross-section at a CMS energy orders of magnitude beyond what can be achieved with terrestrial accelerators. Measurement of an anomalously large neutrino cross-section would indicate new physics (e.g. low string-scale, extra dimensions, precocious unification), while a smaller than expected cross-section would reveal an aspect of QCD evolution. We then discuss aspects of neutrino-primary models for the extreme-energy (EE) cosmic ray data. Primary neutrinos in extant data are motivated by the directional clustering at EE reported by the AGASA experiment. We discuss the impact of the strongly-interacting neutrino hypothesis on lower-energy physics via dispersion relations, the statistical significance of AGASA directional clustering, and the possible relevance of the Z-burst mechanism for existing EE cosmic ray data.

scholarly journals Mass Unspecific Supervised Tagging (MUST) for boosted jets

2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
J. A. Aguilar-Saavedra ◽  
F. R. Joaquim ◽  
J. F. Seabra
Keyword(s):  
Neural Networks ◽  
Transverse Momentum ◽  
Optimal Solution ◽  
New Physics ◽  
Jet Substructure ◽  
Correlation Problem ◽  
Degree Of Confidence ◽  
Input Variables ◽  
High Degree ◽  
Physics Signal

Abstract Jet identification tools are crucial for new physics searches at the LHC and at future colliders. We introduce the concept of Mass Unspecific Supervised Tagging (MUST) which relies on considering both jet mass and transverse momentum varying over wide ranges as input variables — together with jet substructure observables — of a multivariate tool. This approach not only provides a single efficient tagger for arbitrary ranges of jet mass and transverse momentum, but also an optimal solution for the mass correlation problem inherent to current taggers. By training neural networks, we build MUST-inspired generic and multi-pronged jet taggers which, when tested with various new physics signals, clearly outperform the variables commonly used by experiments to discriminate signal from background. These taggers are also efficient to spot signals for which they have not been trained. Taggers can also be built to determine, with a high degree of confidence, the prongness of a jet, which would be of utmost importance in case a new physics signal is discovered.

scholarly journals Anomalies in the Cosmic Microwave Background and Their Non-Gaussian Origin in Loop Quantum Cosmology

2021 ◽  
Vol 8 ◽  
Author(s):  
Ivan Agullo ◽  
Dimitrios Kranas ◽  
V. Sreenath
Keyword(s):  
Cosmic Microwave Background ◽  
Quantum Cosmology ◽  
Statistical Significance ◽  
New Physics ◽  
Common Origin ◽  
Loop Quantum Cosmology ◽  
Microwave Background ◽  
Λcdm Model ◽  
Non Gaussian ◽  
Dipolar Modulation

Anomalies in the cosmic microwave background (CMB) refer to features that have been observed, mostly at large angular scales, and which show some tension with the statistical predictions of the standard ΛCDM model. In this work, we focus our attention on power suppression, dipolar modulation, a preference for odd parity, and the tension in the lensing parameter AL. Though the statistical significance of each individual anomaly is inconclusive, collectively they are significant, and could indicate new physics beyond the ΛCDM model. In this article, we present a brief, but pedagogical introduction to CMB anomalies and propose a common origin in the context of loop quantum cosmology.

scholarly journals Comparing weak- and unsupervised methods for resonant anomaly detection

2021 ◽  
Vol 81 (7) ◽  
Author(s):  
Jack H. Collins ◽  
Pablo Martín-Ramiro ◽  
Benjamin Nachman ◽  
David Shih
Keyword(s):  
Large Hadron Collider ◽  
Anomaly Detection ◽  
Cross Sections ◽  
Hadron Collider ◽  
New Physics ◽  
Classification Performance ◽  
Detection Techniques ◽  
Resonance Search ◽  
Weakly Supervised ◽  
Physics Signal

AbstractAnomaly detection techniques are growing in importance at the Large Hadron Collider (LHC), motivated by the increasing need to search for new physics in a model-agnostic way. In this work, we provide a detailed comparative study between a well-studied unsupervised method called the autoencoder (AE) and a weakly-supervised approach based on the Classification Without Labels (CWoLa) technique. We examine the ability of the two methods to identify a new physics signal at different cross sections in a fully hadronic resonance search. By construction, the AE classification performance is independent of the amount of injected signal. In contrast, the CWoLa performance improves with increasing signal abundance. When integrating these approaches with a complete background estimate, we find that the two methods have complementary sensitivity. In particular, CWoLa is effective at finding diverse and moderately rare signals while the AE can provide sensitivity to very rare signals, but only with certain topologies. We therefore demonstrate that both techniques are complementary and can be used together for anomaly detection at the LHC.

Imaging molecules adsorbed onto electrodes under potential control by scanning probe microscopy

1991 ◽  
Vol 49 ◽  
pp. 376-377 ◽  
Author(s):  
N.J. Tao ◽  
J.A. DeRose ◽  
P.I. Oden ◽  
S.M. Lindsay
Keyword(s):  
Surface Charge ◽  
Environmental Effects ◽  
Scanning Probe Microscopy ◽  
Statistical Significance ◽  
Electrochemical Methods ◽  
Surface Structures ◽  
Scanning Probe ◽  
Potential Control ◽  
Afm Imaging ◽  
Special Circumstances

Clemmer and Beebe have pointed out that surface structures on graphite substrates can be misinterpreted as biopolymer images in STM experiments. We have been using electrochemical methods to react DNA fragments onto gold electrodes for STM and AFM imaging. The adsorbates produced in this way are only homogeneous in special circumstances. Searching an inhomogeneous substrate for ‘desired’ images limits the value of the data. Here, we report on a reversible method for imaging adsorbates. The molecules can be lifted onto and off the substrate during imaging. This leaves no doubt about the validity or statistical significance of the images. Furthermore, environmental effects (such as changes in electrolyte or surface charge) can be investigated easily.

Influence of Maternal Education on Food Consumption and Energy and Nutrient Intake in a Group of Pre-School Children from Madrid

2003 ◽  
Vol 73 (6) ◽  
pp. 439-445 ◽  
Author(s):  
Navia ◽  
Ortega ◽  
Requejo ◽  
Perea ◽  
López-Sobaler ◽  
...  
Keyword(s):  
Food Consumption ◽  
School Children ◽  
Food Habits ◽  
Nutrient Intake ◽  
Maternal Education ◽  
Statistical Significance ◽  
Dietary Adequacy ◽  
Consumption Energy ◽  
Maternal Educational Level ◽  
Energy And Nutrient Intake

A study was conducted on the influence of maternal education level on food consumption, energy and nutrient intake, and dietary adequacy in 110 pre-school children from Madrid, Spain. With increasing maternal education, children consumed more sugar (p < 0.05), fruit (p < 0.05), and fish (p < 0.05). Snacking was more frequent with decreasing maternal education (p < 0.05). Though statistical significance was not reached, the consumption of pre-cooked foods was greater among children of mothers educated to a higher level, a phenomenon probably related to the work situation of these women. With respect to dietary composition, no significant differences were found between groups for macronutrient, fiber and energy intakes, except for energy supplied by polyunsaturated fatty acids (PUFA), which was greater in the children of less educated women (p < 0.01). This is probably due to their greater consumption of sunflower seed oil. The diets of children belonging to well-educated mothers came closer to meeting the recommended intakes for folate, vitamin C, and iodine. It would seem that maternal educational level influences the food habits of children. Mothers with less education may require special advice in this area.

Use of vascular closure devices for endovascular interventions requiring a direct puncture of PETE grafts

VASA ◽  
2018 ◽  
Vol 47 (2) ◽  
pp. 119-124 ◽  
Author(s):  
Artur I. Milnerowicz ◽  
Aleksandra A. Milnerowicz ◽  
Marcin Protasiewicz ◽  
Wiktor Kuliczkowski
Keyword(s):  
Statistical Significance ◽  
Vascular Complications ◽  
Vascular Complication ◽  
Inguinal Region ◽  
Closure Device ◽  
Manual Compression ◽  
Direct Puncture ◽  
Endovascular Interventions ◽  
Vascular Closure Devices ◽  
Closure Group

Abstract. Background: Effectiveness of vascular closure devices during endovascular procedures requiring a direct puncture of a vascular prosthesis placed in the inguinal region is unknown. Patients and methods: The retrospective analysis included 134 patients with a history of polyethylene terephthalate (PETE) graft implantation in the inguinal region. In 20 (15 %) patients, haemostasis was achieved with manual compression, in 21 (16 %) with the StarClose™, and in 93 (69 %) with the AngioSeal™ device. Results: The incidence of vascular complications in the manual compression group was higher (at a threshold of statistical significance) than in the device closure group (45.0 vs. 24.5 %, p = 0.059). The difference was considered statistically significant when manual compression was compared with the AngioSeal™ closure group (45.0 vs. 13.9 %, p < 0.01). The vascular complication rate in the StarClose™ group was significantly higher than in the AngioSeal™ group (71.4 vs. 13.9 %, p < 0.000001). While haematomas were the only vascular complications observed after application of AngioSeal™, both haematomas and pseudoaneurysms were found in the StarClose™ group. Conclusions: The AngioSeal™ vascular closure device provides better local haemostasis than the StarClose™ device or manual compression during endovascular interventions requiring a direct puncture of PETE grafts

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