scholarly journals MODEL INDEPENDENT CONSTRAINTS ON NON-ELECTRONIC FLAVORS IN THE SOLAR BORON NEUTRINO FLUX

2006 ◽  
Vol 21 (22) ◽  
pp. 1761-1768 ◽  
Author(s):  
S. DEV ◽  
SANJEEV KUMAR ◽  
SURENDER VERMA

We perform the most general model-independent analysis of the latest 391-Day Salt Phase SNO Data Set incorporating the super-Kamiokande ES flux measurement and obtain bounds on the antineutrino and sterile neutrino flux in the solar 8 B neutrino flux reaching the detectors on the earth. The muon/tauon antineutrino flux is found to be disallowed at 1.4σ C.L. The sterile flux is found to be nonzero at about 1.26 standard deviations.

2005 ◽  
Vol 20 (27) ◽  
pp. 2083-2093 ◽  
Author(s):  
S. DEV ◽  
SANJEEV KUMAR

The rise-up in boron neutrino spectrum at low energies has been studied within the framework of "pure LMA" scenario. Indirect bounds on the spectral "upturn" have been obtained from the available solar neutrino data. These bounds have been used to demonstrate the efficacy of the precision measurements of the "upturn" for further constraining the neutrino parameter space allowed by SNO salt phase data. The sterile neutrino flux has been constrained in the light of the recent 766.3 Ty KamLAND spectral data.


2016 ◽  
Vol 25 (14) ◽  
pp. 1630028 ◽  
Author(s):  
Francis Halzen

By transforming a cubic kilometer of natural Antarctic ice into a neutrino detector, the IceCube project created the opportunity to observe cosmic neutrinos. We describe the experiment and the complementary methods presently used to study the flux of the recently discovered cosmic neutrinos. In one method, events are selected in which neutrinos interacted inside the instrumented volume of the detector, yielding a sample of events dominated by neutrinos of electron and tau flavor. Alternatively, another method detects secondary muons produced by neutrinos selected for having traveled through the Earth to reach the detector, providing a pure sample of muon neutrinos. We will summarize the results obtained with the enlarged data set collected since the initial discovery and appraise the current status of high-energy neutrino astronomy. The large extragalactic neutrino flux observed points to a nonthermal universe with comparable energy in neutrinos, gamma rays and cosmic rays. Continued observations may be closing in on the source candidates. In this context, we highlight the potential of multimessenger analyses as well as the compelling case for constructing a next-generation detector larger in volume by one order of magnitude.


2005 ◽  
Vol 20 (38) ◽  
pp. 2957-2967 ◽  
Author(s):  
S. DEV ◽  
SANJEEV KUMAR

The possibility of flavor transitions into sterile neutrinos (accompanying the dominant LMA transitions) in the solar boron neutrino flux has been examined in a scenario proposed by Hollanda and Smirnov to overcome some generic problems of the pure LMA scenario. It is found that the most recent SNO salt phase solar neutrino data and the KamLAND 766.3 Ty spectral data, allow for a significant sterile presence in the solar boron neutrino flux reaching the earth.


2020 ◽  
pp. 1-14
Author(s):  
Esraa Hassan ◽  
Noha A. Hikal ◽  
Samir Elmuogy

Nowadays, Coronavirus (COVID-19) considered one of the most critical pandemics in the earth. This is due its ability to spread rapidly between humans as well as animals. COVID_19 expected to outbreak around the world, around 70 % of the earth population might infected with COVID-19 in the incoming years. Therefore, an accurate and efficient diagnostic tool is highly required, which the main objective of our study. Manual classification was mainly used to detect different diseases, but it took too much time in addition to the probability of human errors. Automatic image classification reduces doctors diagnostic time, which could save human’s life. We propose an automatic classification architecture based on deep neural network called Worried Deep Neural Network (WDNN) model with transfer learning. Comparative analysis reveals that the proposed WDNN model outperforms by using three pre-training models: InceptionV3, ResNet50, and VGG19 in terms of various performance metrics. Due to the shortage of COVID-19 data set, data augmentation was used to increase the number of images in the positive class, then normalization used to make all images have the same size. Experimentation is done on COVID-19 dataset collected from different cases with total 2623 where (1573 training,524 validation,524 test). Our proposed model achieved 99,046, 98,684, 99,119, 98,90 In terms of Accuracy, precision, Recall, F-score, respectively. The results are compared with both the traditional machine learning methods and those using Convolutional Neural Networks (CNNs). The results demonstrate the ability of our classification model to use as an alternative of the current diagnostic tool.


Geophysics ◽  
2019 ◽  
Vol 84 (1) ◽  
pp. R1-R10 ◽  
Author(s):  
Zhendong Zhang ◽  
Tariq Alkhalifah ◽  
Zedong Wu ◽  
Yike Liu ◽  
Bin He ◽  
...  

Full-waveform inversion (FWI) is an attractive technique due to its ability to build high-resolution velocity models. Conventional amplitude-matching FWI approaches remain challenging because the simplified computational physics used does not fully represent all wave phenomena in the earth. Because the earth is attenuating, a sample-by-sample fitting of the amplitude may not be feasible in practice. We have developed a normalized nonzero-lag crosscorrelataion-based elastic FWI algorithm to maximize the similarity of the calculated and observed data. We use the first-order elastic-wave equation to simulate the propagation of seismic waves in the earth. Our proposed objective function emphasizes the matching of the phases of the events in the calculated and observed data, and thus, it is more immune to inaccuracies in the initial model and the difference between the true and modeled physics. The normalization term can compensate the energy loss in the far offsets because of geometric spreading and avoid a bias in estimation toward extreme values in the observed data. We develop a polynomial-type weighting function and evaluate an approach to determine the optimal time lag. We use a synthetic elastic Marmousi model and the BigSky field data set to verify the effectiveness of the proposed method. To suppress the short-wavelength artifacts in the estimated S-wave velocity and noise in the field data, we apply a Laplacian regularization and a total variation constraint on the synthetic and field data examples, respectively.


10.3133/tm7c6 ◽  
2012 ◽  
Author(s):  
Christopher T. Muffels ◽  
Willem A. Schreuder ◽  
John E. Doherty ◽  
Marinko Karanovic ◽  
Matthew J. Tonkin ◽  
...  

Metaphysics ◽  
2020 ◽  
pp. 67-71
Author(s):  
O. B Khavroshkin ◽  
V. V Tsyplakov

The detected anomalous neutrino radioisotope (ANRI) absorption or effect allows one to study the variety of interactions of neutrino fluxes with radioactive matter and its consequences. Thus, results were obtained on solar neutrinos v , seismicity and heat flow of the Earth. The study of the features of the mechanical manifestation of the neutrino flux as a mechanical effect of the solar flux v in space on the Pioneer-type spacecraft is promising for many reasons.


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