scholarly journals Modular invariant models of leptons at level 7

2020 ◽  
Vol 2020 (8) ◽  
Author(s):  
Gui-Jun Ding ◽  
Stephen F. King ◽  
Cai-Chang Li ◽  
Ye-Ling Zhou
Keyword(s):  
Modular Forms ◽  
Galois Field ◽  
Special Linear Group ◽  
Type I ◽  
Time Level ◽  
Projective Special Linear Group ◽  
Modular Invariant ◽  
Seesaw Mechanism ◽  
Linearly Independent ◽  
First Time

Abstract We consider for the first time level 7 modular invariant flavour models where the lepton mixing originates from the breaking of modular symmetry and couplings responsible for lepton masses are modular forms. The latter are decomposed into irreducible multiplets of the finite modular group Γ7, which is isomorphic to PSL(2, Z7), the projective special linear group of two dimensional matrices over the finite Galois field of seven elements, containing 168 elements, sometimes written as PSL2(7) or Σ(168). At weight 2, there are 26 linearly independent modular forms, organised into a triplet, a septet and two octets of Γ7. A full list of modular forms up to weight 8 are provided. Assuming the absence of flavons, the simplest modular-invariant models based on Γ7 are constructed, in which neutrinos gain masses via either the Weinberg operator or the type-I seesaw mechanism, and their predictions compared to experiment.

scholarly journals Flavour effects in gravitational leptogenesis

2020 ◽  
Vol 2020 (12) ◽  
Author(s):  
Rome Samanta ◽  
Satyabrata Datta
Keyword(s):  
Mass Spectrum ◽  
Chemical Potential ◽  
Mass Scale ◽  
Lepton Number ◽  
Type I ◽  
Lepton Asymmetry ◽  
Seesaw Mechanism ◽  
Set Up ◽  
The Right ◽  
Lepton Number Violating

Abstract Within the Type-I seesaw mechanism, quantum effects of the right-handed (RH) neutrinos in the gravitational background lead to an asymmetric propagation of lepton and anti-leptons which induces a Ricci scalar and neutrino Dirac-Yukawa coupling dependent chemical potential and therefore a lepton asymmetry in equilibrium. At high temperature, lepton number violating scattering processes try to maintain a dynamically generated lepton asymmetry in equilibrium. However, when the temperature drops down, the interactions become weaker, and the asymmetry freezes out. The frozen out asymmetry can act as a pre-existing asymmetry prior to the standard Fukugita-Yanagida leptogenesis phase (Ti ∼ Mi, where Mi is the mass of ith RH neutrino). It is then natural to consider the viability of gravitational leptogenesis for a given RH mass spectrum which is not consistent with successful leptogenesis from decays. Primary threat to this gravity-induced lepton asymmetry to be able to successfully reproduce the observed baryon-to-photon ratio is the lepton number violating washout processes at Ti ∼ Mi. In a minimal seesaw set up with two RH neutrinos, these washout processes are strong enough to erase a pre-existing asymmetry of significant magnitude. We show that when effects of flavour on the washout processes are taken into account, the mechanism opens up the possibility of successful leptogenesis (gravitational) for a mass spectrum M2 » 109GeV » M1 with M1 ≳ 6.3 × 106 GeV. We then briefly discuss how, in general, the mechanism leaves its imprints on the low energy CP phases and absolute light neutrino mass scale.

Comparative Analysis of the Proteomic Profile of Cattle Hides that Produce Loose and Tight Leather using In-Gel Tryptic Digestion followed by LC-MS/MS

2020 ◽  
Vol 115 (11) ◽  
pp. 399-408
Author(s):  
Catherine Maidment ◽  
Meekyung Ahn ◽  
Rafea Naffa ◽  
Trevor Loo ◽  
Gillian Norris
Keyword(s):  
Type I Collagen ◽  
Raw Material ◽  
Type I ◽  
Collagen Structure ◽  
Proteomic Profile ◽  
Collagen Network ◽  
Collagen Concentration ◽  
Different Types ◽  
Molecular Components ◽  
First Time

Looseness is a defect found in leather that reduces its quality by causing a wrinkly appearance in the finished product, resulting in a reduction in its value. Earlier studies on loose leather using microscopy and Raman spectroscopy reported a change in the collagen structure of loose leather. In this study, proteomics was used to investigate the possible molecular causes of looseness in the raw material, the first time such a study has been carried out. Proteins extracted from two regions of raw hide using two different methods were analysed; those taken from the distal axilla, an area prone to looseness, and those taken from the backbone which is less prone to looseness. Analyses using 1DE-LC-MS/MS showed that although the overall collagen concentration was similar in both areas of the hide, the distribution of the different types of collagen differed.  Specifically, concentrations of type I collagen, and the collagen-associated proteoglycan decorin were lower in samples taken from the distal axilla, symptomatic of a collagen network with excess space seen for these samples using confocal microscopy. This study suggests a possible link between the molecular components of raw cattle hide and looseness and more importantly between the molecular components of skin and skin defects. There is therefore potential to develop biomarkers for looseness which will enable early preventative action.

scholarly journals Radiative Corrections toMhfrom Three Generations of Majorana Neutrinos and Sneutrinos

2015 ◽  
Vol 2015 ◽  
pp. 1-26 ◽  
Author(s):  
S. Heinemeyer ◽  
J. Hernandez-Garcia ◽  
M. J. Herrero ◽  
X. Marcano ◽  
A. M. Rodriguez-Sanchez
Keyword(s):  
Higgs Boson ◽  
Higgs Mass ◽  
Critical Discussion ◽  
Full Detail ◽  
Neutrino Masses ◽  
Type I ◽  
Radiative Corrections ◽  
Seesaw Mechanism ◽  
Three Generations ◽  
Majorana Neutrinos

We study the radiative corrections to the mass of the lightest Higgs boson of the MSSM from three generations of Majorana neutrinos and sneutrinos. The spectrum of the MSSM is augmented by three right handed neutrinos and their supersymmetric partners. A seesaw mechanism of type I is used to generate the physical neutrino masses and oscillations that we require to be in agreement with present neutrino data. We present a full one-loop computation of these Higgs mass corrections and analyze in full detail their numerical size in terms of both the MSSM and the new (s)neutrino parameters. A critical discussion on the different possible renormalization schemes and their implications, in particular concerning decoupling, is included.

scholarly journals A Rare Case of Congenital Methemoglobinemia with secondary polycythemia- Case Report and Literature Review

2019 ◽  
Vol 3 (01) ◽  
pp. 20-23
Author(s):  
Tasneem Ara ◽  
Qazi Smita Haque ◽  
Salma Afrose
Keyword(s):  
Skin Color ◽  
Rare Case ◽  
Heart Diseases ◽  
Final Diagnosis ◽  
Enzyme Deficiency ◽  
Type I ◽  
Methemoglobin Level ◽  
Hands And Feet ◽  
First Time

Congenital heart diseases are common cause of congenital cyanosis with polycythaemia. Congenital methemoglobinemia is a rare cause of lifelong cyanosis with polycythemia. Congenital methemoglobinemia is caused either by enzyme deficiency or by an abnormal Hb (Hb M). Asymptomatic despite presence of severe cyanosis indicates this rare disorder. We are reporting a rare case of polycythemia with cyanosis due to congenital methemoglobinemia. The patient was referred to our centre and attended Hematology OPD (out-patient department) when his routine CBC revealed erythrocytosis. At that time, we found him severely cyanosed especially apparent on lips, tongue, hands and feet. He was diagnosed as a case of congenital methemoglobinemia with 38% blood methemoglobin level (normal value-0.00-2.00%). On view of life long persistent cyanosis, without any cardiopulmonary and neurological abnormality, consanguinity of parent’s marriage, dark colored blood with high methemoglobin level, a final diagnosis of Type I enzyme deficiency congenital methemoglobinemia was made. He was treated with oral ascorbic acid 250 mg twice daily. At follow up after 6 months his skin color improved and RBC count returned to normal. We are reporting this case of congenital methemoglobinemia for the first time in Bangladesh to emphasize the importance of this rare entity in the differential diagnosis of asymptomatic cyanosis with polycythemia.

scholarly journals Weak scale right-handed neutrino as pseudo-Goldstone fermion of spontaneously broken $$ \mathrm{U}{(1)}_{L_{\mu }-{L}_{\tau }} $$

2021 ◽  
Vol 2021 (9) ◽  
Author(s):  
Anjan S. Joshipura ◽  
Ketan M. Patel
Keyword(s):  
Prototype Model ◽  
Neutrino Masses ◽  
Type I ◽  
Decay Vertex ◽  
Electroweak Scale ◽  
Seesaw Mechanism ◽  
Cosmological Constraints ◽  
Flavour Violation ◽  
Soft Supersymmetry Breaking ◽  
Parity Breaking

Abstract Possibility of a Right-Handed (RH) neutrino being a Goldstone fermion of a spontaneously broken global U(1) symmetry in a supersymmetric theory is considered. This fermion obtains mass from the supergravity effects leading to a RH neutrino at the electroweak scale with a mass similar to the gravitino mass. A prototype model realizing this scenario contains just three gauge singlet superfields needed for the type I seesaw mechanism. Masses of the other two neutrinos are determined by the U(1) breaking scale which too can be around the electroweak scale. Light neutrinos obtain their masses in this scenario through (a) mixing with the RH neutrinos (type I seesaw), (b) mixing with neutralinos (R-parity breaking), (c) indirectly through mixing of the RH neutrinos with neutralinos, and (d) radiative corrections. All these contributions are described by the same set of a small number of underlying parameters and provide a very constrained and predictive framework for the neutrino masses which is investigated in detail for various choices of U(1) symmetries. It is found that flavour independent U(1) symmetries cannot describe neutrino masses if the soft supersymmetry breaking terms are flavour universal and one needs to consider flavour dependent symmetries. Considering a particular example of Lμ− Lτ symmetry, it is shown that viable neutrino masses and mixing can be obtained without introducing any flavour violation in the soft sector. The leptonic couplings of Majoron are worked out in the model and shown to be consistent with various laboratory, astrophysical and cosmological constraints. The neutrino data allows sizeable couplings between the RH neutrinos and Higgsinos which can be used to probe the pseudo-Goldstone fermion at colliders through its displaced decay vertex.

scholarly journals Investigating two heavy neutral leptons neutrino seesaw mechanism at SHiP

2019 ◽  
Vol 34 (08) ◽  
pp. 1950047
Author(s):  
Marco Chianese ◽  
Damiano F. G. Fiorillo ◽  
Gennaro Miele ◽  
Stefano Morisi
Keyword(s):  
Neutrino Mass ◽  
Double Beta Decay ◽  
Type I ◽  
Mass Generation ◽  
Seesaw Mechanism ◽  
Mixing Angle ◽  
Mechanism Model ◽  
Neutrino Mass Generation ◽  
Generation Mechanisms ◽  
The Masses

One of the main purposes of SHiP experiment is to shed light on neutrino mass generation mechanisms like the so-called seesaw. We consider a minimal type-I seesaw neutrino mass mechanism model with two heavy neutral leptons (right-handed or sterile neutrinos) with arbitrary masses. Extremely high active-sterile mixing angle requires a correlation between the phases of the Dirac neutrino couplings. Actual experimental limits on the half-life of neutrinoless double beta decay [Formula: see text]-rate on the active-sterile mixing angle are not significative in constraining the masses or the mixing measurable by SHiP.

Custom Contrast Testing: Current Trends and a New Approach

2018 ◽  
Vol 93 (5) ◽  
pp. 223-244 ◽  
Author(s):  
Ryan D. Guggenmos ◽  
M. David Piercey ◽  
Christopher P. Agoglia
Keyword(s):  
Type I Error ◽  
Type I ◽  
Visual Evaluation ◽  
New Approach ◽  
Accounting Research ◽  
Elevated Type ◽  
Current Trends ◽  
Comprehensive Picture ◽  
Contrast Analysis ◽  
First Time

ABSTRACT Contrast analysis has become prevalent in experimental accounting research since Buckless and Ravenscroft (1990) introduced it to the accounting literature over 25 years ago. Since its initial introduction, the scope of contrast testing has expanded, yet guidance as to the most appropriate methods of specifying, conducting, interpreting, and exhibiting these tests has not. We survey the use of contrast analysis in the recent literature and propose a three-part testing approach that provides a more comprehensive picture of contrast results. Our approach considers three pieces of complementary evidence: the visual evaluation of fit, traditional significance testing, and quantitative evaluation of the contrast variance residual. Our measure of the contrast variance residual, q2, is proposed for the first time in this work. After proposing our approach, we walk through six common contrast testing scenarios where current practices may fall short and our approach may guide researchers. We extend Buckless and Ravenscroft (1990) and contribute to the accounting research methods literature by documenting current contrast analysis practices that result in elevated Type I error and by proposing a potential solution to mitigate these concerns.

Transport Properties of Type II Sodium-Silicon Clathrates

2005 ◽  
Vol 886 ◽  
Author(s):  
Matt Beekman ◽  
Jan Grkyo ◽  
George S. Nolas
Keyword(s):  
Thermal Conductivity ◽  
Sodium Content ◽  
Type I ◽  
Type Ii ◽  
Conductivity Measurements ◽  
Scanning Calorimetry ◽  
Resistivity Measurements ◽  
Silicon Clathrates ◽  
Covalently Bonded ◽  
First Time

ABSTRACTWe have synthesized the type II silicon clathrates Na1Si136 and Na8Si136, and report on the electrical and thermal transport in these materials. The crystal structure consists of a covalently bonded silicon framework in which sodium guest atoms are encapsulated inside the silicon host framework. Differential scanning calorimetry measurements show the compounds decompose above 600°C to diamond-structure silicon. Temperature dependant electrical resistivity measurements show the specimens to have an insulating character, with magnitudes that decrease with increasing sodium content. For the first time, thermal conductivity measurements on type II sodium-silicon clathrates are presented. The thermal conductivity is very low for both specimens, and for Na8Si136 exhibits a clear dip in the range from 50 to 70 K. These data suggest that the “rattling” behavior observed in type I clathrates may also be present in type II clathrates.

scholarly journals Conformal GUT inflation, proton lifetime and non-thermal leptogenesis

2019 ◽  
Vol 79 (11) ◽  
Author(s):  
K. Sravan Kumar ◽  
Paulo Vargas Moniz
Keyword(s):  
Conformal Symmetry ◽  
Lepton Number ◽  
Baryon Asymmetry ◽  
Neutrino Masses ◽  
Type I ◽  
Gauge Bosons ◽  
Seesaw Mechanism ◽  
Grand Unified Theories ◽  
Unified Theories ◽  
Proton Lifetime

AbstractIn this paper, we generalize Coleman–Weinberg (CW) inflation in grand unified theories (GUTs) such as $$\text {SU}(5)$$SU(5) and $$\text {SO}(10)$$SO(10) by means of considering two complex singlet fields with conformal invariance. In this framework, inflation emerges from a spontaneously broken conformal symmetry. The GUT symmetry implies a potential with a CW form, as a consequence of radiative corrections. The conformal symmetry flattens the above VEV branch of the CW potential to a Starobinsky plateau. As a result, we obtain $$n_{s}\sim 1-\frac{2}{N}$$ns∼1-2N and $$r\sim \frac{12}{N^2}$$r∼12N2 for $$N\sim $$N∼ 50–60 e-foldings. Furthermore, this framework allow us to estimate the proton lifetime as $$\tau _{p}\lesssim 10^{40}$$τp≲1040 years, whose decay is mediated by the superheavy gauge bosons. Moreover, we implement a type I seesaw mechanism by weakly coupling the complex singlet, which carries two units of lepton number, to the three generations of singlet right handed neutrinos (RHNs). The spontaneous symmetry breaking of global lepton number amounts to the generation of neutrino masses. We also consider non-thermal leptogenesis in which the inflaton dominantly decays into heavy RHNs that sources the observed baryon asymmetry. We constrain the couplings of the inflaton field to the RHNs, which gives the reheating temperature as $$10^{6}\text { GeV}\lesssim T_{R}<10^{9}$$106GeV≲TR<109 GeV.

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