scholarly journals New physics from oscillations at the DUNE near detector, and the role of systematic uncertainties

2021 ◽  
Vol 2021 (8) ◽  
Author(s):  
Pilar Coloma ◽  
Jacobo López-Pavón ◽  
Salvador Rosauro-Alcaraz ◽  
Salvador Urrea
Keyword(s):  
Cross Sections ◽  
New Physics ◽  
Short Baseline ◽  
Near Detector ◽  
Beam Focusing ◽  
Neutrino Production ◽  
Systematic Uncertainties ◽  
Mixing Matrix ◽  
The Impact

Abstract We study the capabilities of the DUNE near detector to probe deviations from unitarity of the leptonic mixing matrix, the 3+1 sterile formalism and Non-Standard Interactions affecting neutrino production and detection. We clarify the relation and possible mappings among the three formalisms at short-baseline experiments, and we add to current analyses in the literature the study of the νμ→ ντ appearance channel. We study in detail the impact of spectral uncertainties on the sensitivity to new physics using the DUNE near detector, which has been widely overlooked in the literature. Our analysis shows that this plays an important role on the results and, in particular, that it can lead to a strong reduction in the sensitivity to sterile neutrinos from νμ→ νe transitions, by more than two orders of magnitude. This stresses the importance of a joint experimental and theoretical effort to improve our understanding of neutrino nucleus cross sections, as well as hadron production uncertainties and beam focusing effects. Nevertheless, even with our conservative and more realistic implementation of systematic uncertainties, we find that an improvement over current bounds in the new physics frameworks considered is generally expected if spectral uncertainties are below the 5% level.

The Basque-Cantabrian Basin: a natural laboratory to study the reactivation of a hyperextended system

2020 ◽  
Author(s):  
Jordi Miro Padrisa ◽  
Patricia Cadenas ◽  
Rodolphe Lescoutre ◽  
Josep Anton Muñoz ◽  
Gianreto Manatschal
Keyword(s):  
Cross Sections ◽  
Late Triassic ◽  
Entire Area ◽  
Early Stages ◽  
3D Geometry ◽  
Present Part ◽  
The Impact ◽  
Basque Cantabrian Basin ◽  
Natural Laboratory

<p>The Basque – Cantabrian Basin (BCB) corresponds to a Mesozoic hyperextended rift basin that was subsequently reactivated from Late Cretaceous to Cenozoic and is at present part of the Pyrenean orogen. Numerous studies have addressed the role of rift inheritance on the formation of orogens, but little consideration has been given to the rift segmentation and the along strike variability. In the BCB, most studies focused on a section at the central part of the basin, despite the amount of geological and geophysical data available on the entire area, which make it a perfect natural laboratory to study the reactivation of a hyperextended basin.</p><p>The aim of this study is threefold: (I) reveal the 3D geometry and the along strike variability of the BCB by doing three N-S transversal cross sections from east to west; (II) define the rift domains and their limits; and (III) study the impact of rift inheritance during the compressional reactivation mainly focusing on the former distal rift domains.</p><p>Our preliminary results show that the BCB is affected by a multistage and polyphase rift evolution including a first, widespread Permo – Triassic rift phase including Late Triassic salt, a Late Jurassic to Barremian extensional phase and a more prominent Aptian to Middle Cenomanian hyperextension phase.  This complex rift template had a major impact on the subsequent reactivation and can explain some of the along strike variabilities observed within the three regional cross sections. To the east, the BCB was completely reactivated and transported to the south over the Late Triassic salt, which acted as a decoupling level. On the contrary, the westernmost section preserves the rift-related structures only weakly reactivated, providing direct insights on the early stages of reactivation. Our observations show that underthrusting/subduction initiates within the exhumed mantle domain, while during initial collision, the necking domains acted as a buttress. Decollement levels during early stages are located in the former rift distal domains and use serpentinized mantle rocks, while during collision they migrate to more external parts and use intra-basement decoupling levels such as the ductile middle crust and/or salt horizons.</p><p>Key words: Rift inheritance, Pyrenees, Basque – Cantabrian Basin, hyperextension.</p>

scholarly journals Tau-neutrino as a probe of nonstandard interactions via charged Higgs and W′ contribution

2014 ◽  
Vol 29 (07) ◽  
pp. 1450040
Author(s):  
Ahmed Rashed
Keyword(s):  
Standard Model ◽  
Cross Sections ◽  
New Physics ◽  
Mixing Angles ◽  
Tau Neutrino ◽  
Standard Model Cross Section ◽  
The Standard Model ◽  
Charged Higgs ◽  
Reactor Mixing ◽  
The Impact

We discuss the impact of the presence of a charged Higgs boson and a W′ gauge boson on the tau-neutrino nucleon scattering ντ+N→τ-+X and [Formula: see text]. We show the effect of the new physics on the quasielastic, Δ-resonance and deep inelastic scattering. The measurements for the atmospheric and reactor mixing angles θ23 and θ13 in the appearance analyses νμ →ντ and [Formula: see text] are based on the Standard Model cross-section of the above processes. The measured mixing angles are changed when considering the new physics contributions to those reactions, assuming the Standard Model cross-sections. We include form factor effects in the new physics calculations and find the deviations of the mixing angles can be significant and can depend on the energy of the neutrino.

scholarly journals Role of Polar vs Non-polar Configurations in the Decay of 268Sg* Compound Nucleus Within the Skyrme Energy Density Formalism

2021 ◽  
Vol 9 (1) ◽  
pp. 61-66
Author(s):  
Rajni Mittal ◽  
Kirandeep Sandhu ◽  
M. K. Sharma
Keyword(s):  
Experimental Data ◽  
Energy Density ◽  
Cross Section ◽  
Compound Nucleus ◽  
Cross Sections ◽  
Fission Cross Section ◽  
Cluster Decay ◽  
The Impact ◽  
Adequate Agreement

The effect of polar and non-polar configurations is investigated in the decay of 268Sg* compound nucleus formed via spherical projectile (30Si) and prolate deformed target (238U) using the dynamical cluster decay model. The SSK and GSkI skyrme forces are used to investigate the impact of polar and nonpolar (equatorial) configurations on the preformation probability P0 and consequently on the fission cross-sections of 268Sg* nucleus. For non-polar configuration some secondary peaks corresponding to magic shells Z=28 and N=50 are observed, whose magnitude is significantly suppressed for the polar counterpart. The effect of polar and non-polar configurations is further analyzed in reference to barrier lowering parameter ΔVB. The calculated fission cross-section find adequate agreement with experimental data for chosen set of skyrme forces.

scholarly journals Adjusting neutrino interaction models and evaluating uncertainties using NOvA near detector data

2020 ◽  
Vol 80 (12) ◽  
Author(s):  
M. A. Acero ◽  
P. Adamson ◽  
G. Agam ◽  
L. Aliaga ◽  
T. Alion ◽  
...  
Keyword(s):  
Cross Sections ◽  
Neutrino Interaction ◽  
Neutrino Beam ◽  
Order Effects ◽  
Interaction Models ◽  
Near Detector ◽  
Neutrino Oscillation Experiment ◽  
Systematic Uncertainties ◽  
Interaction Cross Sections ◽  
Detector Design

AbstractThe two-detector design of the NOvA neutrino oscillation experiment, in which two functionally identical detectors are exposed to an intense neutrino beam, aids in canceling leading order effects of cross-section uncertainties. However, limited knowledge of neutrino interaction cross sections still gives rise to some of the largest systematic uncertainties in current oscillation measurements. We show contemporary models of neutrino interactions to be discrepant with data from NOvA, consistent with discrepancies seen in other experiments. Adjustments to neutrino interaction models in GENIE are presented, creating an effective model that improves agreement with our data. We also describe systematic uncertainties on these models, including uncertainties on multi-nucleon interactions from a newly developed procedure using NOvA near detector data.

scholarly journals Exploring Light Sterile Neutrinos at Long Baseline Experiments: A Review

Universe ◽  
2020 ◽  
Vol 6 (3) ◽  
pp. 41
Author(s):  
Antonio Palazzo
Keyword(s):  
Cp Violation ◽  
Sterile Neutrino ◽  
Mass Hierarchy ◽  
Short Baseline ◽  
Neutrino Mass Hierarchy ◽  
Long Baseline ◽  
Discovery Potential ◽  
Neutrino Experiments ◽  
The Impact

Several anomalies observed in short-baseline neutrino experiments suggest the existence of new light sterile neutrino species. In this review, we describe the potential role of long-baseline experiments in the searches of sterile neutrino properties and, in particular, the new CP-violation phases that appear in the enlarged 3 + 1 scheme. We also assess the impact of light sterile states on the discovery potential of long-baseline experiments of important targets such as the standard 3-flavor CP violation, the neutrino mass hierarchy, and the octant of θ 23 .

scholarly journals Observational constraints on the origin of the elements

2019 ◽  
Vol 631 ◽  
pp. A80 ◽  
Author(s):  
Maria Bergemann ◽  
Andrew J. Gallagher ◽  
Philipp Eitner ◽  
Manuel Bautista ◽  
Remo Collet ◽  
...  
Keyword(s):  
Cross Sections ◽  
Stellar Population ◽  
Local Thermodynamic Equilibrium ◽  
Element Abundance ◽  
One Dimensional ◽  
Systematic Biases ◽  
Non Local ◽  
Hydrodynamical Simulations ◽  
The Impact

Manganese (Mn) is a key Fe-group element, commonly employed in stellar population and nucleosynthesis studies to explore the role of SN Ia. We have developed a new non-local thermodynamic equilibrium (NLTE) model of Mn, including new photo-ionisation cross-sections and new transition rates caused by collisions with H and H− atoms. We applied the model in combination with one-dimensional (1D) LTE model atmospheres and 3D hydrodynamical simulations of stellar convection to quantify the impact of NLTE and convection on the line formation. We show that the effects of NLTE are present in Mn I and, to a lesser degree, in Mn II lines, and these increase with metallicity and with the effective temperature of a model. Employing 3D NLTE radiative transfer, we derive a new abundance of Mn in the Sun, A(Mn) = 5.52 ± 0.03 dex, consistent with the element abundance in C I meteorites. We also applied our methods to the analysis of three metal-poor benchmark stars. We find that 3D NLTE abundances are significantly higher than 1D LTE. For dwarfs, the differences between 1D NLTE and 3D NLTE abundances are typically within 0.15 dex, however, the effects are much larger in the atmospheres of giants owing to their more vigorous convection. We show that 3D NLTE successfully solves the ionisation and excitation balance for the RGB star HD 122563 that cannot be achieved by 1D LTE or 1D NLTE modelling. For HD 84937 and HD 140283, the ionisation balance is satisfied, however, the resonance Mn I triplet lines still show somewhat lower abundances compared to the high-excitation lines. Our results for the benchmark stars confirm that 1D LTE modelling leads to significant systematic biases in Mn abundances across the full wavelength range from the blue to the IR. We also produce a list of Mn lines that are not significantly biased by 3D and can be reliably, within the 0.1 dex uncertainty, modelled in 1D NLTE.

scholarly journals Вероятность процесса захвата двух электронов быстрым ионом Не-=SUP=-2+-=/SUP=- у атома Хе при различных параметрах удара

2021 ◽  
Vol 47 (20) ◽  
pp. 31
Author(s):  
А.А. Басалаев ◽  
М.Н. Панов ◽  
О.В. Смирнов
Keyword(s):  
Impact Parameter ◽  
Cross Sections ◽  
Differential Cross ◽  
Differential Cross Sections ◽  
Helium Atoms ◽  
The Impact ◽  
Electron Shells

Differential cross sections for scattering of helium atoms formed at collisions of He2+ ions with kinetic energies of 1.97, 3.00, and 7.17 keV/a.m.u with Xe atoms in processes with the formation of slow xenon ions with charges 2 - 4 have been measured. The projectiles deflection function is calculated. The probability of all these processes occurring at various values of the impact parameter of colliding particles is determined. The role of the electron shells of the Xe atom 5 (s, p) and 4 (s, p, d) for the capture of two electrons is determined depending on the speed of approach of the colliding particles, the impact parameter and the charge of the formed xenon ions.

scholarly journals Parton distributions in the SMEFT from high-energy Drell-Yan tails

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Admir Greljo ◽  
Shayan Iranipour ◽  
Zahari Kassabov ◽  
Maeve Madigan ◽  
James Moore ◽  
...  
Keyword(s):  
Cross Sections ◽  
Neutral Current ◽  
Light Quark ◽  
High Energy ◽  
New Physics ◽  
Effective Field ◽  
Distribution Functions ◽  
High Mass ◽  
Parton Distribution Functions ◽  
The Impact

Abstract The high-energy tails of charged- and neutral-current Drell-Yan processes provide important constraints on the light quark and anti-quark parton distribution functions (PDFs) in the large-x region. At the same time, short-distance new physics effects such as those encoded by the Standard Model Effective Field Theory (SMEFT) would induce smooth distortions to the same high-energy Drell-Yan tails. In this work, we assess for the first time the interplay between PDFs and EFT effects for high-mass Drell-Yan processes at the LHC and quantify the impact that the consistent joint determination of PDFs and Wilson coefficients has on the bounds derived for the latter. We consider two well-motivated new physics scenarios: 1) electroweak oblique corrections ($$ \hat{W},\hat{Y} $$ W ̂ , Y ̂ ) and 2) four-fermion interactions potentially related to the LHCb anomalies in R(K(*)). We account for available Drell-Yan data, both from unfolded cross sections and from searches, and carry out dedicated projections for the High-Luminosity LHC. Our main finding is that, while the interplay between PDFs and EFT effects remains moderate for the current dataset, it will become a significant challenge for EFT analyses at the HL-LHC.

Oxygen K near edge structures studied with multiple scattering calculations

1988 ◽  
Vol 46 ◽  
pp. 504-505
Author(s):  
Xudong Weng ◽  
Peter Rez
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Partial Cross Section ◽  
Energy Window ◽  
Edge Structure ◽  
Fine Structures ◽  
Hydrogenic Model ◽  
Electron Energy Loss ◽  
Quantitative Chemical

In electron energy loss spectroscopy, quantitative chemical microanalysis is performed by comparison of the intensity under a specific inner shell edge with the corresponding partial cross section. There are two commonly used models for calculations of atomic partial cross sections, the hydrogenic model and the Hartree-Slater model. Partial cross sections could also be measured from standards of known compositions. These partial cross sections are complicated by variations in the edge shapes, such as the near edge structure (ELNES) and extended fine structures (ELEXFS). The role of these solid state effects in the partial cross sections, and the transferability of the partial cross sections from material to material, has yet to be fully explored. In this work, we consider the oxygen K edge in several oxides as oxygen is present in many materials. Since the energy window of interest is in the range of 20-100 eV, we limit ourselves to the near edge structures.

Intergroup Threat and Outgroup Attitudes

2013 ◽  
Vol 44 (5) ◽  
pp. 311-319 ◽  
Author(s):  
Marco Brambilla ◽  
David A. Butz
Keyword(s):  
Gay Men ◽  
Social Group ◽  
Welfare Recipients ◽  
Intergroup Attitudes ◽  
Social Policies ◽  
Intergroup Threat ◽  
Economic Threat ◽  
The Impact ◽  
General Climate

Two studies examined the impact of macrolevel symbolic threat on intergroup attitudes. In Study 1 (N = 71), participants exposed to a macrosymbolic threat (vs. nonsymbolic threat and neutral topic) reported less support toward social policies concerning gay men, an outgroup whose stereotypes implies a threat to values, but not toward welfare recipients, a social group whose stereotypes do not imply a threat to values. Study 2 (N = 78) showed that, whereas macrolevel symbolic threat led to less favorable attitudes toward gay men, macroeconomic threat led to less favorable attitudes toward Asians, an outgroup whose stereotypes imply an economic threat. These findings are discussed in terms of their implications for understanding the role of a general climate of threat in shaping intergroup attitudes.

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