Adiabatic Motion of a Quantum Particle in a Two-Dimensional Magnetic Field

The adiabatic motion of a charged, spinning, quantum particle in a two - dimensional magnetic field is studied. A suitable set of operators generalizing the cinematical momenta and the guiding center operators of a particle moving in a homogeneous magnetic field is constructed. This allows us to separate the two degrees of freedom of the system into a {\sl fast} and a {\sl slow} one, in the classical limit, the rapid rotation of the particle around the guiding center and the slow guiding center drift. In terms of these operators the Hamiltonian of the system rewrites as a power series in the magnetic length \lb=\sqrt{\hbar c\over eB} and the fast and slow dynamics separates. The effective guiding center Hamiltonian is obtained to the second order in the adiabatic parameter \lb and reproduces correctly the classical limit.Comment: 17 pages, LaTe

Quantum Charged Spinning Particles in a Strong Magnetic Field (a Quantal Guiding Center Theory)

A quantal guiding center theory allowing to systematically study the separation of the different time scale behaviours of a quantum charged spinning particle moving in an external inhomogeneous magnetic filed is presented. A suitable set of operators adapting to the canonical structure of the problem and generalizing the kinematical momenta and guiding center operators of a particle coupled to a homogenous magnetic filed is constructed. The Pauli Hamiltonian rewrites in this way as a power series in the magnetic length $l_B= \sqrt{\hbar c/eB}$ making the problem amenable to a perturbative analysis. The first two terms of the series are explicitly constructed. The effective adiabatic dynamics turns to be in coupling with a gauge filed and a scalar potential. The mechanism producing such magnetic-induced geometric-magnetism is investigated in some detail.Comment: LaTeX (epsfig macros), 27 pages, 2 figures include

Ray helicity: a geometric invariant for multi-dimensional resonant wave conversion

For a multicomponent wave field propagating into a multidimensional conversion region, the rays are shown to be helical, in general. For a ray-based quantity to have a fundamental physical meaning it must be invariant under two groups of transformations: congruence transformations (which shuffle components of the multi-component wave field) and canonical transformations (which act on the ray phase space). It is shown that for conversion between two waves there is a new invariant not previously discussed: the intrinsic helicity of the ray

Reactor Fuel Fraction Information on the Antineutrino Anomaly

We analyzed the evolution data of the Daya Bay reactor neutrino experiment in terms of short-baseline active-sterile neutrino oscillations taking into account the theoretical uncertainties of the reactor antineutrino fluxes. We found that oscillations are disfavored at $2.6\sigma$ with respect to a suppression of the $^{235}\text{U}$ reactor antineutrino flux and at $2.5\sigma$ with respect to variations of the $^{235}\text{U}$ and $^{239}\text{Pu}$ fluxes. On the other hand, the analysis of the rates of the short-baseline reactor neutrino experiments favor active-sterile neutrino oscillations and disfavor the suppression of the $^{235}\text{U}$ flux at $3.1\sigma$ and variations of the $^{235}\text{U}$ and $^{239}\text{Pu}$ fluxes at $2.8\sigma$. We also found that both the Daya Bay evolution data and the global rate data are well-fitted with composite hypotheses including variations of the $^{235}\text{U}$ or $^{239}\text{Pu}$ fluxes in addition to active-sterile neutrino oscillations. A combined analysis of the Daya Bay evolution data and the global rate data shows a slight preference for oscillations with respect to variations of the $^{235}\text{U}$ and $^{239}\text{Pu}$ fluxes. However, the best fits of the combined data are given by the composite models, with a preference for the model with an enhancement of the $^{239}\text{Pu}$ flux and relatively large oscillations.Comment: 9 page

Diagonalization of multicomponent wave equations with a Born-Oppenheimer example

A general method to decouple multicomponent linear wave equations is presented. First, the Weyl calculus is used to transform operator relations into relations between c-number valued matrices. Then it is shown that the symbol representing the wave operator can be diagonalized systematically up to arbitrary order in an appropriate expansion parameter. After transforming the symbols back to operators, the original problem is reduced to solving a set of linear uncoupled scalar wave equations. The procedure is exemplified for a particle with a Born-Oppenheimer-type Hamiltonian valid through second order in h. The resulting effective scalar Hamiltonians are seen to contain an additional velocity-dependent potential. This contribution has not been reported in recent studies investigating the adiabatic motion of a neutral particle moving in an inhomogeneous magnetic field. Finally, the relation of the general method to standard quantum-mechanical perturbation theory is discussed

Glycolytic potential and ultimate muscle pH values in red deer (Cervus elaphus) and fallow deer (Dama dama)

The ultimate pH value of meat (measured at approx. 24 hours post slaughter) gives information about the technological quality, i.e. shelf life, colour, water-holding properties and tenderness and is a direct consequence of muscle glycogen (energy) levels at slaughter. It may therefore also indicate whether or not the animal has been exposed to stressful energy depleting events prior to slaughter. In the present study, 141 animals (130 red deer (Cervus elaphus) and 11 fallow deer (Dama dama) were included to investigate the relationship between ultimate pH and residual glycogen concentration in red deer and fallow deer M. longissimus. In addition, the muscle glycogen content and ultimate pH values in three red deer muscles (Mm. triceps brachii, longissimus and biceps femoris) were studied. M. triceps brachii had higher ultimate pH and lower glycogen content compared with the other two studied muscles. The frequency of intermediate DFD (5.8≤ pH<6.2) was 5.4% in red deer M. longissimus, compared with 9.1% in fallow deer, while the frequency of DFD (pH≥ 6.2) was much lower in red deer (3.8%) than in fallow deer (54.5%). A curvilinear relationship between ultimate pH and total glucose concentration (glycogen and glucose) 30 min post slaughter in red deer and fallow deer M. longissimus was found. The relationship between muscle pH and lactic acid concentration however, was indicated to be linear. A significant variation in total glucose concentration at ultimate pH below 5.80 was observed, including values in the range from 18 to 123 mmol/kg wet tissue. It was concluded that further studies are needed to further explore the relationship between muscle glycogen content and technological and sensory quality attributes of meat from different deer species.Abstract in Swedish / Sammanfattning:Köttets pH-värde (mätt ca 24 timmar efter slakt) har stor betydelse för den teknologiska kvaliteten som t. ex. hållbarhet, färg, vattenhållande förmåga och mörhet. Glykogenförrådet (energinivån) i djurens muskulatur vid slakt är helt avgörande för köttets slutliga pH-värde. Därför kan pH-värdet också indikera om hanteringen av slaktdjur varit skonsam eller om stora mängder muskelenergi har förbrukats vid stress. I vår undersökning ingick 141 hjortar (130 kronhjortar (Cervus elaphus) och 11 dovhjortar (Dama dama) för att studera sambandet mellan köttets pH-värde och glykogeninnehållet i M. longissimus. Glykogeninnehåll och pH-värden i 3 muskler från kronhjort (Mm. triceps brachii, longissimus och biceps femoris) undersöktes också. M. triceps brachii hade högre pH-värde och lägre glykogeninnehåll jämfört med de två andra musklerna. Det var inte så stor skillnad i frekvensen av intermediär DFD (pH-värden mellan 5,8 og 6,2) mellan de två hjortarterna (5,4% för kronhjort och 9,1% för dovhjort), däremot var frekvensen av DFD (pH-värden över 6,2) mycket låg hos kronhjort (3,8%) jämfört med dovhjort (54,5%). Det fanns ett kurvlinjärt samband mellan slutligt pH-värde i köttet och total glukoskoncentration (glykogen + glukos) mätt i M. longissimus 30 min efter slakt för både kron- och dovhjort. Ett linjärt samband mellan pH-värde och koncentration av mjölksyra i M. longissimus kunde också visas. Vi fann en mycket stor varitation i glukoskoncentration (18−123 mmol/kg våtvikt) när köttets pH-värdet var 5,8 eller lägre. Det behövs fler undersökningar för att vidare klargöra sambanden mellan glykogeninnehåll i muskulaturen och teknologisk och sensorisk kvalitet i olika typer av hjortkött