Theories of weak interactions and astrophysical evidence
SummaryIt has been proposed in an earlier paper that photons can interact weakly with neutrinos. Assuming this photon-neutrino coupling, the effect of energy loss due to the pair-annihilation process and the photoneutrino process on the evolutionary time scales of a 15.6M⊙ star has been discussed. In the typical model of Hayashi, Hoshi and Sugimoto (HHS), the lifetimes for carbon burning and later phases have been calculated assuming the photon-neutrino coupling, and is compared with the results obtained by HHS according to the (eν)(eν) coupling. In case of the
$$\gamma \nu \bar \nu $$
 coupling, the ratio of the number of blue supergiants (He-burning stars) to red supergiants (stars in C-burning and later stages) is found to be ≲ 10 with the initial concentration of carbonXc=0.5, whereas according to the (eν)(eν) coupling, the corresponding ratio is found to be nearly 33. According to astrophysical observations, this ratio is found to be nearly unity within a factor 1.5. It is noted that the result according to the
$$\gamma \nu \bar \nu $$
 coupling becomes significantly better in comparison with the (eν)(eν) coupling. Also, in view of the uncertatinties regarding the total luminosity in the red-supergiant phase as well as the rate of C+C relation, we can consider the result obtained according to the
$$\gamma \nu \bar \nu $$
 coupling to be in reasonable proximity to the «observed» value. From this, we argue that stars seem to «favour» the photon-neutrino coupling theory rather than the current-current coupling theory of weak interactions.RiassuntoSi è proposta, precedentemente, la possibilità di un’interazione debole dei fotoni con i neutrini. Supponendo valido l’accoppiamento fotone-neutrino, si è discusso l’effetto della perdita di energia sulle scale di tempo evolutivo di una stella di 15.6M⊙. Col modello tipico di Hayashi, Hoshi e Sugimoto (HHS), si sono calcolate le vite medie della combustione del carbonio e delle fasi successive, nell’ipotesi di accoppiamento fotoneneutrino. Si è confrontato il risultato così ottenuto con quello ricavato da HHS secondo l’accoppiamento (eν)(eν). Nel caso di accoppiamento
$$\gamma \nu \bar \nu $$
, si trova che il rapporto fra le stelle supergiganti blu (stelle a combustione di He) e quelle rosse (stelle a combustione di C ed in fasi successive) è ≲ 10, posto che la concentrazione iniziale di carbonio,Xc, sia 0.5, mentre, nel caso di accoppiamento (eν)(eν), il suddetto rapporto risulta essere circa 33. Basandosi su osservazioni astrofisiche il rapporto è invece circa unitario entro un fattore di 1.5. Si constata che il valore ottenuto con l’accoppiamento
$$\gamma \nu \bar \nu $$
 è migliore, e in modo significativo, del valore ottenuto con l’altro tipo di accoppiamento. Se si considera poi l’attuale incertezza, sia per quanto concerne la luminosità totale nella fase di super giganti rosse sia per quanto concerne il rapporto della relazione C+C, si può ritenere il risultato ottenuto con l’accoppiamento
$$\gamma \nu \bar \nu $$
 come quello che più approssima il valore «osservato». Da tutto ciò segue che l’osservazione delle stelle sembra «favorire» la teoria dell’accoppiamento fotone-neutrino per le interazioni deboli, piuttosto che quella dell’accoppiamento corrente-corrente.РеэюмеВ предыдушей работе было предположено, что фотоны могут слабо вэаимодействовать с нейтрино. Предполагая зту фотон-нейтринную свяэь, было рассмотрено влияние потери знергии, обусловленной процессом аннигиляции пар и фото-нейтринным процессом, на зволюционные масщтабы времени для эвеэды 15.6M⊙. В типичной модели Хайащи, Хопщ и Сугимото были вычислены времена жиэни для горения углерода и более поэдние фаэы, предполагая фотон-нейтринную свяэь. Полученные реэультаты сравниваются с реэультатами, полученными Хайащи, Хощи и Сугимото в соответствии с (eν)(eν) свяэью. В случае
$$\gamma \nu \bar \nu $$
 свяэи получено, что отнощение числа голубых супергигантов (эвеэды с горением Не) к числу красных супергигантов (эвеэды в стадии горения С и более поэдних стадиях) составляет ≲10 с начальной концентрацией углеродаXc=0.5, в то время как в соответствии с (eν)(eν) свяэью, соответствуюшее отнощение приблиэительно равно 33. Найдено, что согласно астрофиэическим наблюдениям зто отнощение составляет приблиэительно единицу, в пределах множителя 1.5. Отмечается, что реэультат в соответствии с
$$\gamma \nu \bar \nu $$
 свяэью становится эначительно лучще по сравнению с (eν)(eν) свяэью. Также, в виду неопределенностей относительно полной светимости в фаэе красного супергиганта, а также скорости C + C реакции, мы можем считать, что реэультат, полученный в соответствии с
$$\gamma \nu \bar \nu $$
 свяэью, находится в раэумной области блиэости с « наблюдаемой » величиной. Иэ зтого мы утверждаем, что эвеэды, по-видимому, « отдают предпочтение » теории фотон-нейтринной свяэи по сравнению с теорией ток-токовой свяэи слабых вэqaимодействий.

title: Stochastic field theory at finite temperature, supersymmetry, and witten index
abstract: Finite temperature supersymmetry is studied here from the point of view of stochastic field theory and the formalism of thermofield dynamics. It is shown that the Witten index can take only the values 1 and ½ in this formalism. It is pointed out that when at a critical temperature T c , below which supersymmetry is spontaneously broken, the zero energy mode is given by a thermal doublet of opposite statistics when the index is 1. However, when the index is ½, the zero energy mode is given by a thermal doublet of the same fermionic statistics.

title: EQUIVALENCE OF STOCHASTIC, KLAUDER AND GEOMETRIC QUANTIZATION
abstract: The relativistic generalization of stochastic quantization helps us to introduce a stochastic-phase-space formulation when a relativistic quantum particle appears as a stochastically extended one. The nonrelativistic quantum mechanics is obtained in the sharp point limit. This also helps us to introduce a gauge-theoretical extension of a relativistic quantum particle when for a fermion the group structure of the gauge field is SU(2). The sharp point limit is obtained when we have a minimal contribution of the residual gauge field retained in the limiting procedure. This is shown to be equivalent to the geometrical approach to the phase-space quantization introduced by Klauder if it is interpreted in terms of a universal magnetic field acting on a free particle moving in a higher-dimensional configuration space when quantization corresponds to freezing the particle to its first Landau level. The geometric quantization then appears as a natural consequence of these two formalisms, since the Hermitian line bundle introduced there finds a physical meaning in terms of the inherent gauge field in stochastic-phase-space formulation or in the interaction with the magnetic field in Klauder quantization.

title: Random fields, ising model and bosson-fermion phase transition
abstract: SummaryIt is here shown that when the stochastic quantization procedure is introduced to a massive Thirring fermion where the latter is described as a bound state of massless oscillators interacting through a gradient term in a linear chain, we find that a boson-fermion phase transition occurs at a critical temperatureT =Tc, and atT >Tc supersymmetry is restored. In this scheme supersymmetry is broken by the generation of mass which arises due to the presence of the gradient term.

title: EXTENDED CONFORMAL GROUP, SUPERSYMMETRY, AND GEOMETRICAL PROPERTIES OF HADRONS
abstract: We have studied the interrelation among conformal symmetry, internal symmetry and super-symmetry and have shown that extended conformal group which includes, apart from conformal transformation, space, time and conformal reflection can give rise to internal symmetry algebra as well as supersymmetry algebra. To achieve this result, we have dealt with conformal spinors which are taken to be the constituents of the hadrons and these split into two Cartan semispinors or Dirac spinors in the Minkowski space, giving rise to the particle and antiparticle configurations. Supersymmetry is broken here just by the mass term and as such no massless hadron can exist in nature. The internal symmetry arises from the discrete symmetry of reflection. The most significant feature of this formalism is that the symmetry structure helps us to explain the meson-baryon mass difference in an elegant way and the role of fictitious superpartners is completely avoided. Again, any baryon number nonconserving process like proton decay is found to be forbidden by the Lorentz invariance. Finally, it is noted that though the discrete symmetry of reflection is taken to be the origin of the internal symmetry, topological nontrivial structures like strings do not appear here and this also avoids the possibility of the nonconservation of global charge.

title: QUANTUM HALL SKYRMIONS IN THE FRAMEWORK OF O(4) NONLINEAR SIGMA MODEL
abstract: A new framework for quantum Hall skyrmions in O(4) nonlinear sigma model is studied here. The size and energy of the skyrmions are determined incorporating the quartic stability term in the Lagrangian. Moreover, the introduction of a θ-term determines the spin and statistics of these skyrmions.

title: Search for Higgs bosons of the universal extra dimensions at the large Hadron collider
abstract: The Higgs sector of the Universal Extra Dimensions (UED) has a rather involved setup. With one extra space dimension, the main ingredients to the construct are the higher Kaluza-Klein (KK) excitations of the Standard Model Higgs boson and the fifth components of the gauge fields which on compactification appear as scalar degrees of freedom and can mix with the former thus leading to physical KK-Higgs states of the scenario. In this work, we explore in detail the phenomenology of such a Higgs sector of the UED with the Large Hadron Collider (LHC) in focus. We work out relevant decay branching fractions involving the KK-Higgs excitations. Possible production modes of the KK-Higgs bosons are then discussed with an emphasis on their associated production with the third generation KK-quarks and that under the cascade decays of strongly interacting UED excitations which turn out to be the only phenomenologically significant modes. It is pointed out that the collider searches of such Higgs bosons face generic hardship due to soft end-products which result from severe degeneracies in the masses of the involved excitations in the minimal version of the UED (MUED). Generic implications of either observing some or all of the KK-Higgs bosons at the LHC are discussed.

title: Probing Higgs bosons via the type III seesaw mechanism at the LHC
abstract: We show that the type III seesaw mechanism opens up a promising possibility of searching the Higgs boson in the $b \bar b$ channel through the Higgs production associated with a charged lepton coming from the decay of the triplet seesaw particle. In particular we look for the $2b$ signals with trileptons or same-sign dileptons to construct the Higgs and the triplet fermion mass and calculate the reach with the integrated luminosity of 10 fb$^{-1}$ at the 14 TeV LHC.

title: Unusual Higgs boson signal in R-parity violating nonminimal supersymmetric models at the LHC
abstract: We predict an unconventional background free signal of the Higgs boson in $R$-parity violating nonminimal supersymmetric models at the Large Hadron Collider (LHC). The signal comprises dilepton plus four hadronic jets and two large displaced vertices. The displaced leptons and jets are coming from the decay of the lightest supersymmetric particle (LSP), which is predominantly a gauge-singlet neutrino. A pair of such LSPs can couple to a Higgs boson, created via gluon fusion. We have analyzed two cases - one corresponding to the tree-level Higgs boson mass and another with the one-loop corrected mass of the Higgs boson. A reliable Higgs mass reconstruction using this signal can lead to discovery at the LHC with center-of-mass energy $\sqrt{s}=14~\rm{TeV}$ and 5 fb$^{-1}$ of integrated luminosity $(\mathcal{L})$. Even at $\sqrt{s}=7~\rm{TeV}$ and $\mathcal{L}$ = 5 fb$^{-1}$, a reasonable number of events are expected. Besides, mass reconstruction of a gauge-singlet LSP can provide an estimate of the seesaw scale.

title: Probing non-universal gaugino masses via Higgs boson production under SUSY cascades at the LHC: a detailed study
abstract: Cascade decays of Supersymmetric (SUSY) particles are likely to be prolific sources of Higgs bosons at the Large Hadron Collider (LHC). In this work, we explore, with the help of detailed simulation, the role of non-universal gaugino masses in the production of the Higgs bosons under SUSY cascades. The analysis is carried out by choosing an appropriate set of benchmark points with non-universal gaugino masses in the relevant SUSY parameter space and then contrasting the resulting observations with the corresponding cases having universal relationship among the same. It is shown that even of data at an early phase of the LHC-run with 10 fb−1 one would be able to see, under favourable situations, the imprint of non-universal gaugino masses by reconstructing various Higgs boson resonances and comparing their rates. With increased accumulated luminosities, the indications would naturally become distinct over a larger region of the parameter space.

title: Evidence of multifractality and constant specific heat in hadronic collisions at high energies