Probing physics beyond the standard model in diatomic molecules

De nos jours, l'incomplétude du modèle standard des particules est largement reconnue. L'une de ses failles les plus évidentes est le manque d'explication de l'énorme excédent de matière par rapport à l'antimatière dans l'univers, que l'on appelle l'asymétrie baryonique de l'univers. De nouvelles violations de CP (conjugaison de charge et parité spatiale) absentes dans le modèle standard sont supposées être responsables de cette asymétrie. Une telle violation pourrait être observée dans la matière ordinaire à travers un ensemble d'interactions violant les symétries de parité et de renversement du temps (impaires pour P,T) dont les prépondérantes sont les interactions du moment dipolaire électrique de l'électron (eEDM), électron-nucléon scalaire-pseudoscalaire (enSPS) et du moment quadripolaire magnétique nucléaire (nMQM). Ainsi, une preuve expérimentale d'une constante d'interaction impaire pour P,T serait une preuve de cette nouvelle physique au-delà du modèle standard. Le calcul des paramètres moléculaires correspondants est réalisé en utilisant une approche d'interaction de configurations relativiste à quatre composantes dans des molécules diatomiques polaires contenant un actinide, qui sont des systèmes particulièrement appropriés pour les expèriences eEDM, tels que ThO qui a permis d'assigner à l'eEDM la borne supérieure la plus contraignante et ThF+ qui sera utilisé dans une expérience à venir. Ces résultats sont d'une importance cruciale dans l'interprétation des mesures puisque les constantes fondamentales ne peuvent être évaluées que si l'on associe les mesures de décalages énergétiques et les paramètres moléculaires théoriques.Nowadays, the incompleteness of the Standard Model of particles is largely acknowledged. One of its most obvious shortcomings is the lack of explanation for the huge surplus of matter over antimatter in the universe, the so-called Baryon Asymmetry of the Universe. New CP (Charge conjugation and spatial Parity) violations absent in the SM are assumed to be responsible for this asymmetry. Such a violation could be observed in ordinary matter through a set of interactions violating both parity and time-reversal symmetries (P,T-odd), among which the preponderant ones are the electron Electric Dipole Moment (eEDM), the electron-nucleon scalar-pseudoscalar (enSPS) and the nuclear magnetic quadrupole moment (nMQM) interactions. Hence, an experimental evidence of a non-zero P,T-odd interaction constant would be a probe of this New Physics beyond the Standard Model. The calculation of the corresponding molecular parameters is performed by making use of an elaborate four-component relativistic configuration interaction approach in polar diatomic molecules containing an actinide, that are particularly adequate systems for eEDM experiments, such as ThO that allowed for assigning the most constraining upper bound on the eEDM and ThF+ that will be used in a forthcoming experiment. Those results will be of crucial importance in the interpretation of the measurements since the fundamental constants can only be evaluated if one combines both experimental energy shift measurements and theoretical molecular parameters

The association between carotid intima media thickness and genetic risk score (GRS) among two different study populations of the Bogalusa Heart Study.

<p>The GRS was calculated as a weighted sum of coronary artery disease risk alleles from 24 known variants.</p><p>Adjustments: Model 1 –unadjusted; Model 2 – age, sex and Body Mass Index; Model 3a (European ancestry) – age, sex, body mass index, total cholesterol, low density lipoprotein -cholesterol, triglycerides and systolic blood pressure; Model 3b (African ancestry) – age, sex, body mass index, and systolic blood pressure. Abbreviations: GRS, Genetic Risk Score, S.E., Standard Error.</p><p>*Change of CIMT in millimetres corresponding to a change of one standard deviation in the risk score.</p

General characteristics of the three study populations with available ultrasound and genotype data.

<p>All units are expressed as mean (SD) except for dichotomous variables.</p><p>Abbreviations: CIMT, Carotid artery Intima Media Thickness; CAE Carotid Artery Elasticity; HDL, High Density Lipoprotein; LDL, Low Density Lipoprotein; BP, Blood Pressure; BMI, body mass index.</p

The association between sub-clinical atherosclerosis measured from the carotid artery and the genetic risk score formed from 24 risk variants previously associated with coronary artery disease.

<p>Adjustments: Model 1 – unadjusted; Model 2 – age, sex and Body Mass Index; Model 3a – age, sex, body mass index, apoliprotein A, apolipoprotein B, systolic blood pressure and waist circumference; Model 3b – age, sex, body mass index, blood glucose, waist circumference and diastolic blood pressure.</p><p>*Beta for a change of one standard deviation in the risk score.</p><p>**For an increase of one risk allele in the GRS_24SNP/CAD.</p><p>***The 6-year incidence of carotid atherosclerosis is defined as the occurrence of substantial CIMT (age-, sex- and BMI- adjusted CIMT- value over 90% percentile) or plaque in 2007 in subjects who did not have substantial CIMT or plaque in 2001.</p><p>Abbreviations: S.E., Standard Error; OR, Odds Ratio; CI, Confidence interval.</p