Modern Physics Letters A

The Array for Microwave Background Anisotropy is a 7-element interferometer sited on Mauna Loa, Hawaii. The seven 60cm telescopes are mounted on a 6-meter platform, and operates at 3mm wavelength. In October 2006, the telescope was officially dedicated and renamed as the Y. T. Lee AMiBA. During 2007, scientific operations have begun, after a long process of calibration and testing. At the time of this meeting, six clusters of galaxies have been detected and mapped via the inverse Compton scattering of the Cosmic Microwave Background radiation, also known as the Sunyaev-Zel'dovich Effect.

Models where the accelerated expansion of our Universe is caused by a quintessence scalar field are reviewed. In the framework of high energy physics, the physical nature of this field is discussed and its interaction with ordinary matter is studied and explicitly calculated. It is shown that this coupling is generically too strong to be compatible with local tests of gravity. A possible way out, the chameleon effect, is also briefly investigated.

Searches for parity violation in hadronic systems started soon after the evidence for parity violation in β-decay of ⁶⁰Co was presented by Madame Chien-Shiung Wu and in π and μ decay by Leon Lederman in 1957. The early searches for parity violation in hadronic systems did not reach the sensitivity required and only after technological advances in later years was parity violation unambiguously established. Within the meson-exchange description of the strong interaction, theory and experiment meet in a set of seven weak meson-nucleon coupling constants. Even today, after almost five decades, the determination of the seven weak meson-nucleon couplings is incomplete. Parity violation in nuclear systems is rather complex due to the intricacies of QCD. More straight forward in terms of interpretation are measurements of the proton-proton parity-violating analyzing power (normalized differences in scattering yields for positive and negative helicity incident beams), for which there exist three precision experiments (at 13.6, at 45, and 221 MeV). To-date, there are better possibilities for theoretical interpretation using effective field theory approaches.

The situation with regard to the measurement of the parity-violating analyzing power or asymmetry in polarized electron scattering is quite different. Although the original measurements were intended to determine the electro-weak mixing angle, with the current knowledge of the electro-weak interaction and the great precision with which electro-weak radiative corrections can be calculated, the emphasis has been to study the structure of the nucleon, and in particular the strangeness content of the nucleon. A whole series of experiments (the SAMPLE experiment at MIT-Bates, the G0 experiment and HAPPEX experiments at Jefferson Laboratory (JLab), and the PVA4 experiment at MAMI) have indicated that the strange quark contributions to the charge and magnetization distributions of the nucleon are tiny. These measurements if extrapolated to zero degrees and zero momentum transfer have also provided a factor five improvement in the knowledge of the neutral weak couplings to the quarks.

Choosing appropriate kinematics in parity-violating electron-proton scattering permits nucleon structure effects on the measured analyzing power to be precisely controlled. Consequently, a precise measurement of the ‘running’ of sin²θ_w or the electro-weak mixing angle has become within reach. The experiment at Jefferson Laboratory is to measure this quantity to a precision of about 4%. This will either establish conformity with the Standard Model of quarks and leptons or point to New Physics as the Standard Model must be encompassed in a more general theory required, for instance, by a convergence of the three couplings (strong, electromagnetic, and weak) to a common value at the GUT scale.

The upgrade of CEBAF at Jefferson Laboratory to 12 GeV, will allow a new measurement of sin²θ_W in parity-violating electron-electron scattering with an improved precision to the current better measurement (the SLAC E158 experiment) of the ‘running’ of sin²θ_W away from the Z⁰ pole. Preliminary design studies of such an experiment show that a precision comparable to the most precise individual measurements at the Z⁰ pole (to about ±0.00025) can be reached. The result of this experiment will be rather complementary to the experiment in terms of sensitivity to New Physics.

The cosmological QCD transition is studied using lattice simulations. The order of the transition is determined via a finite volume analysis. It is found to be an analytic crossover. The transition temperature is determined in physical units using three different definitions. All results are obtained using four different lattice spacings (a ≈ 0.3, 0.2, 0.15 and 0.12 fm) and a continuum extrapolation.

Results from the High Resolution Fly's Eye (HiRes) experiment and the Pierre Auger Observatory (PAO) on the observation of the Greissen-Zatsepin-Kuzmin cutoff in the cosmic ray spectrum are presented. Both experiments observe a cutoff consistent with the GZK predictions with a five and six sigma significance respectively. The nature of the cosmic ray composition near the GZK cutoff is discussed as well as the recent claim of a correlation of the highest energy cosmic rays with AGNs in the Southern sky.

In the highest energy range on the cosmic ray observation, previous-generation experiments were terminated in these years. The ongoing experiments have introduced a hybrid technique of a widely spread surface array and atmospheric fluorescence detectors. This hybrid technique with a large aperture is expected to calibrate those two methods, only one of which was used in the previous-generation experiments. The Telescope Array (TA) experiment is one of those hybrid-type experiments located in Utah, USA. The TA construction was completed in 2007 and our observation phase is now in progress. This report presents the current status and the first preliminary data.

It is shown how high energy neutrino beams from very distant sources can be utilized to learn about many properties of neutrinos such as lifetimes, mass hierarchy, mixing, minuscule pseudo-Dirac mass splittings and other exotic properties; in addition, the production mechanism of neutrinos in astrophysical sources can also be elucidated.

We critically review the cosmological EW and QCD phase transitions. The EW and QCD phase transitions would have proceeded dynamically since the expansion of the universe determines the quench rate and critical behaviors at the onset of phase transition slow down the phase transition. We introduce a real-time quench model for dynamical phase transitions and describe the evolution using a canonical real-time formalism. We find the correlation function, the correlation length and time and then discuss the cosmological implications of dynamical phase transitions on EW and QCD phase transitions in the early universe.

I give a brief and idiosyncratic overview of the cosmological constant paradox.

I describe and critically evaluate a variety of methods, from simple parametrizations to non-parametric methods, to model the background expansion history in the presence of dark energy. Motivated by these approaches, I review the prospects of determining the properties of dark energy with future experiments, in particular the Dark Energy Survey (DES) and SuperNova/Acceleration Probe (SNAP). Finally, I outline the importance of being able to constrain whole classes of dark energy models, and present recent work that comprehensively studied the observational signature of general scalar field models.

In this review article, we go over some of the consequences that the interactions between dark energy and dark matter may have for the dynamics of the Universe and its observational signatures.

We investigate the cosmological evolution of the new-agegraphic dark energy model which was recently proposed to explain the dark energy-dominated universe. For this purpose, we derived differential equations for density parameters and solved them numerically. We found that there exist a critical value for undetermined parameter of new-agegraphic density to obtain a stable and accessible evolution in the far past. Furthermore, this parameter seems to be fixed as the critical value for consistence.

The simple fact that the present closure contributions in dark matter and dark energy are nearly equal begs the question as to whether they could be different aspects of the same physical phenomenon. Here, we review constraints several postulates as to how this coincidence could be achieved. These include: 1) The possibility that the dark matter decays producing a bulk viscosity in the cosmic fluid; 2) cosmic acceleration produced by the inflow of dark matter from a bulk dimension in brane-world cosmology; and 3) The possibility of relativistic corrections to the Friedmann equation from the presence of local inhomogeneities. Constraints and observational tests of each of these cosmologies are proposed.

How the field excitations play the role of dark energy is explored. There has been the suggestion by Sahni and Wang (1999) that quintessence with rapidly oscillating modes can provide repulsive gravity and drive the cosmic acceleration. A specific model of oscillating quintessence in this scenario with less fine tuning is presented by Gu in arXiv:0711.3606. This natural model not only provides a working example, but also largely increases the feasibility of the oscillating quintessence scenario.

We investigate the modified gravity theories in terms of the effective dark energy models. We compare the cosmic expansion history and the linear growth in different models. We also study the evolution of linear cosmological perturbations in modified theories of gravity assuming the Palatini formalism. We find the stability of the superhorizon metric evolution depends on models. We also study the matter density fluctuation in the general gauge and show the differential equations in super and sub-horizon scales.

The neutron electric dipole moment (EDM) provides unique information on CP violation and physics beyond the Standard Model. We first review the history of experimental searches for neutron electric dipole moment. The status of future neutron EDM experiments, including experiments using ultra-cold neutrons produced in superfluid helium, will then be presented.

Neutrinos play the critical roles in nucleosyntheses of light-to-heavy mass elements in core-collapse supernovae (SNe). The light element synthesis is affected strongly by neutrino oscillations (MSW effect) through the ν-process in outer layers of supernova explosions. Specifically the ⁷Li and ¹¹B yields increase by factors of 1.9 and 1.3 respectively in the case of large mixing angle solution, normal mass hierarchy, and sin² 2θ₁₃ = 2 × 10⁻³ compared to those without the oscillations. In the case of inverted mass hierarchy or nonadiabatic 13-mixing resonance, the increment of their yields is much smaller. We thus propose that precise constraint on mass hierarchy and sin² 2θ₁₃ is given by future observations of Li/B ratio or Li abundance in stars and presolar grains which are made from supernova ejecta. Gamma ray burst (GRB) nucleosynthesis in contrast is not affected strongly by thermal neutrinos from the central core which culminates in black hole (BH), although the effect of neutrinos from proto-neutron star prior to black hole formation is still unknown. We calculate GRB nucleosynthesis by turning off the thermal neutrinos and find that the abundance pattern is totally different from ordinary SN nucleosynthesis which satisfies the universality to the solar abundance pattern.

The ANITA (ANtarctic Impulsive Transient Antenna) experiment is a balloon-borne neutrino telescope which consists of an array of 32 broad-band horn antennas. It successfully completed a 35 day flight over Antarctica during the 2006-2007 austral summer. The primary goal of ANITA is to search for astrophysical neutrinos with energies E > 10¹⁹eV by detecting radio Cherenkov signals from neutrino induced showers in the Antarctic ice. We present preliminary results from ongoing analyses of ANITA data.

The status and plans of a research program on the development of ultra-low-energy germanium detectors with sub-keV sensitivities are reported. We survey the scientific goals which include the observation of neutrino-nucleus coherent scattering, the studies of neutrino magnetic moments, as well as the searches of WIMP dark matter. In particular, a threshold of 100-200 eV and a sub-keV background comparable to underground experiments were achieved with prototype detectors. New limits were set for WIMPs with mass between 3–6 GeV. The prospects of the realization of full-scale experiments are discussed.

The muon charge ratio of ultrahigh energy cosmic rays may provide information to detect the composition of the primary cosmic rays. We propose to extract the charge information of high energy muons in very inclined extensive air showers by analyzing their relative lateral positions in the shower transverse plane.

We discuss the observational effects of the direct coupling of neutrino magnetic moment with electromagnetic field through Pauli interaction in extreme conditions. We calculate the neutrino pair creation rate from the instability of the strong magnetic field possibly in the vicinity of astrophysical compact objects and the enhancement of neutrino production rates in the high energy collider experiments as well as in the high energy cosmic ray experiments.

Judging from the fact that the planet Jupiter is bigger in size than the Earth by 10³ while is smaller than the Sun by 10³, the solar neutrinos, when encounter the Jupiter, may have some visible effects. We estimate how much energy/power carried by solar neutrinos get transferred by this unique process. Solar neutrinos, despite of their feeble neutral weak current interactions, might deposit enough energy in the Jupiter.

I discuss the possibility of generating the observed baryon number in the universe through the lepton-number violating processes in a class of SO(10) grand unification theories. The key ingredient is the CP violating decay of the heavy right-handed neutrinos out of thermal equilibrium.

While the importance of phase space constraints for gravitational clustering of neutrinos (which are fermions) is well recognized, the explicit use of such constraints to limit neutrino emission from ultra energetic sources has not been stressed. Special and general relativistic phase space constraints are shown to limit neutrino luminosities in compact sources in various situations.

The primordial curvature fluctuation spectrum is reconstructed in terms of the cosmic inversion method using the Wilkinson Microwave Anisotropy Probe data of the cosmic microwave background temperature anisotropy. Applying the covariance matrix analysis, the reconstructed spectrum is decomposed into statistically independent band powers. It is found that while statistically significant deviation from a simple power-law spectrum is found for first-year data, no such deviation is found for the three-year data except possibly at one point near the border of the wavenumber domain where accurate reconstruction is possible. This result, however, does not necessarily rule out theories predicting modulations in the power spectrum.

Low quadrupole power in the cosmic microwave background (CMB) temperature anisotropies has been a puzzle since WMAP data release. In this talk I will demonstrate that the minimum variance optimization (MVO), a methodology used by many authors including the WMAP science team to separate the CMB from foreground contamination, serves not only to extract the CMB, but to subtract the “cosmic covariance”, an intrinsic correlation between the CMB and the foregrounds. Such subtraction induces low variance in the signal via MVO, which in turn propagates into the multipoles, causing a quadrupole deficit with more than 90% CL. As we do not know the CMB and the foregrounds a priori, and their correlation is subtracted by the MVO in any case, there is therefore an unknown error in the quadrupole power even before the cosmic variance interpretation. We combine the MVO and Monte Carlo simulations, assuming CMB is a Gaussian random field, and the estimated quadrupole power falls in [308.13, 401.97] μK² (at 1 − σ level).

There is some observational evidence for earlier evolution of clusters of galaxies than predicted in the standard ΛCDM model with a Gaussian primordial density fluctuation field, and a low value for the mass variance parameter (σ₈). Particularly difficult in this model is the interpretation of possible excess CMB anisotropy on cluster scales as due to the Sunyaev-Zeldovich (S-Z) effect. We have calculated S-Z power spectra in the standard model, and in two alternative models which predict higher cluster abundance - a model with non-Gaussian PDF, and an early dark energy model. As anticipated, the levels of S-Z power in the latter two models are significantly higher than in the standard model, and in good agreement with current measurements of CMB anisotropy at high multipole values. Our results provide a sufficient basis for testing the viability of the three models by future high quality measurements of cluster abundance and the anisotropy induced by the S-Z effect.

We present a method for measuring higher-order weak lensing distortions of faint background galaxies, namely the weak gravitational flexion, by fully extending the Kaiser, Squires & Broadhurst method to include higher-order lensing image characteristics (HOLICs) introduced by Okura, Umetsu, & Futamase. Our HOLICs formalism allows accurate measurements of flexion from practical observational data in the presence of non-circular, anisotropic point spread function. We have applied our method to ground-based Subaru observations of the massive galaxy cluster A1689 at a redshift of z = 0.183. From the high-precision measurements of spin-1 first flexion, we obtain a high-resolution mass map in the central region of A1689. The reconstructed mass map shows a bimodal feature in the central 4′ × 4′ region of the cluster. The major, pronounced mass peak is associated with the brightest cluster galaxy and central cluster members, while the secondary peak is associated with a local concentration of bright galaxies. In Fourier space we separate the reconstructed mass distribution into cluster and subhalo components, from which we obtain projected subhalo masses associated with the primary and the secondary peaks to be M₁ = (2.2 ± 0.4) × 10¹³M_⊙/h, and M₂ = (1.1 ± 0.3) × 10¹³M_⊙/h, respectively.

We studied the dependence of morphology and luminosity of the SDSS galaxies on the environmental factors. The environmental factors considered include the local density due to the nearest neighbor galaxy ρ_n, morphology of the nearest neighbor, and the large-scale background density. We found the local environment set up by the nearest neighbor galaxy gives strong effects on the galaxy morphology. The probability for a galaxy to have an early morphological type critically depends on whether or not ρ_n is above the virialization density. We conclude that the well-known morphology-density relation is basically due to the interactions between galaxy pairs. Dependence of galaxy morphology on the large-scale density is found only because there is a statistical correlation between the average pair separation and the large-scale background density. We also found that galaxy luminosity depends on ρ_n, and that, when the large-scale density is fixed, more isolated galaxies are more likely to be recent merger products. We propose a scenario that a series of morphology and luminosity transformation occur through a series of distant/close interactions and mergers, which results in the morphology-luminosity-local density relation.

Weak-lensing induced by clusters of galaxies can probe the total mass distribution out to the virial radius of the cluster, regardless of the nature of the mass or its dynamical state. To make a robust analysis, the cluster and background galaxy populations need to be separated. The E/S0 sequence of a cluster defines a boundary redward of which a reliable weak-lensing signal can be obtained from background galaxies, uncontaminated by the cluster. Below this limit, the signal is diluted by the proportion of unlensed cluster members. Employing deep Subaru and HST/ACS images of the massive cluster A1689, we use this dilution effect to carefully separate between the cluster members and the background, and thus derive the cluster light profile and luminosity functions to large radius. The light profile of A1689 is found to decline steadily to the limit of the data, r < 2 h⁻¹Mpc, with a constant slope, d log(L)/d log(r) = −1.12 ± 0.06. We derive a cluster luminosity function with a flat faint-end slope of α = −1.05 ± 0.07, nearly independent of radius and with no faint upturn to M_i′ < −12. The major advantage of this new approach is that no subtraction of far-field background counts is required.

We discuss how various mechanisms, including type-2 Randall-Sundrum and Dvali-Shifman, may be combined to create possibly realistic domain-wall-brane models with one extra infinite dimension.

Even though the chaotic inflation is one of the most popular inflation models for its simple dynamics and compelling resolutions to the initial condition problems, its realization in supergravity has been considered a challenging task. We discuss how the chaotic inflation dominated by the D-term can be induced in supergravity, which would give a new perspective on the inflation model building in supergravity.

We construct a dual description of technicolor theory based on the D4/D8 brane configuration. From the gauge/gravity correspondence, we explore the oblique correction (STU) parameters. The fermion fields are introduced at the intersections of D-branes and their masses are generated via massive gauge bosons from open strings stretching between D-branes. This talk is based on our paper Ref. 1.

Motivated by the possibility of formulating a strings/black hole correspondence in AdS space, we extract the Hagedorn behavior of thermal AdS₃ bosonic string from 1-loop partition function of SL(2,R) WZW model. We find that the Hagedorn temperature is monotonically increasing as the AdS radius shrinks, reaches a maximum of order of string scale set by the unitarity bound of the CFT for internal space. The resulting density of states near the Hagedorn temperature resembles the form as for strings in flat space and is dominated by the space-like long string configurations. We also examine strings on BTZ background obtained through SL(2, Z) transformation. We find a tachyonic divergence for a BTZ black hole of string scale size.

Closed string field theory is constructed by stochastically quantizing a matrix model for Polyakov loops that describes phases of a large N gauge theory at finite temperature. Coherent states in this string field theory describes winding string condensation which has been expected to cause topology change from thermal AdS geometry to AdS-Schwarzschild black hole geometry. D-branes in this closed string field theory is also discussed. Based on a talk given at CosPA 2007, Taipei.

We investigate the physical implications of the noncommutative geometry in inflationary scenario. Firstly we study the noncommutative inflation with a time-dependent noncommutativity between space and time and find that the scalar perturbation power spectrum depends sensitively on the time varying of the spacetime noncommutativity. Secondly, we discuss the spatially noncommutative effect on the non-Gaussianities of primordial cosmological perturbation. In the lowest order of noncommutativity and slow-roll parameter, we find that in the models with small speed of sound the noncommutative modifications could be observable if assuming a relatively low string scale. It turns out that the corrections are sensitive to the speed of sound and the choice of string length scale, and the shapes of the corrected non-Gaussianities are distinct from that of ordinary ones.

In this note, we refine the racetrack inflation model constructed in Ref. 3 by including the open string modulus. This modulus encodes the embedding of our braneworld inside some Calabi-Yau throat. We argue that in generic this open string modulus dynamically runs with the inflaton field thanks to its nonlinear coupling. A full analysis becomes difficult because the scalar potential changes progressively during the inflation epoch. Nevertheless, by explicit construction we are still able to build a realistic model through appropriate choices of the initial conditions.

Non-commutativity of spacetime at the Planck scale may deform the usual dispersion relations. And these deformed dispersion relations could lead to the accelerating phase without a scalar field. In this paper, we have calculated the spectral index and the running of spectral index in a non-commutative inflation model. Non-commutative inflation with thermal radiation gives a scale invariant spectrum in the limit w → −1 and negative running spectral index which are consistent with the WMAP 3-year results.

Recently we have shown that to the second-order perturbations, the density and velocity perturbation equations of general relativistic zero-pressure, irrotational, single-component fluid in a spatially flat background coincide exactly with the ones known in Newton's theory without using the gravitational potential. Here, we present results relaxing all the assumptions made in the previous works and present the general relativistic correction terms arising due to pressure, multi-component, background spatial curvature, and rotation. We show that even in the multi-component no general relativistic correction terms appear in the zero-pressure, irrotational fluids in a flat background. Thus, the relativistic/Newtonian correspondence of the density and velocity perturbations equations continues even in the multi-component situation. However, the pressure, background curvature, rotation lead to pure general relativistic correction terms to the second order. For the fluid including the pressure, the relativistic corrections appear even in the level of background and linear perturbation equations. In the small-scale limit, to the second order, relativistic equations of density and velocity perturbations including the rotation coincide with the ones in Newton's gravity. We include the cosmological constant in the background world model which is consistent with the currently favored cosmology.

It is shown that, in the context of split supersymmetry, a simple model with a single complex scalar field can produce chaotic inflation and generate the observed amount of baryon asymmetry via the Affleck-Dine mechanism. Combining with constraints from WMAP data, all parameters in the model can be determined to within a narrow range. Possible effects due to non-equilibrium dynamics in the Affleck-Dine mechanism of baryogenesis are also examined.

We show how thermal leptogenesis induced by the CP-violating decay of a right-handed neutrino (RHN) can be compatible to the assumption of quintessential kination, i.e., to a cosmological background model where the energy density of the early Universe is assumed to be dominated by the kinetic term of a quintessence field during some epoch of its evolution. The phenomenology depends on the temperature T_r above which kination dominates over radiation. We show that for some choice of T_r not far from the RHN mass M, M/100 < T_r < M, the efficiency for leptogenesis can be even larger than in the standard scenario of radiation domination. On the other hand, when T_r ≪ M a super-weak wash-out regime is attained, with a strong suppression of the efficiency. In this case successful leptogenesis depends sensitively on ΔL = 1 scattering processes and requires a resonant CP violation effect of order unity. Moreover, the condition T_r > 5 MeV (M/TeV) (0.05 eV/m) must be verified, with m the effective neutrino mass scale.

Quark matter both in terrestrial experiment and in astrophysics is briefly reviewed. Astrophysical quark matter could appear in the early Universe, in compact stars, and as cosmic rays. Emphasis is put on quark star as the nature of pulsars. Possible astrophysical implications of experiment-discovered sQGP are also concisely discussed.

We examine dark matter annihilation in the Universe today. We first discuss the suggestion that the Galactic positron flux, which is difficult to account for with astrophysical sources, is produced by the annihilation of dark matter in the Galactic halo. We show that the positrons produced would necessarily be accompanied by a flux of gamma rays which exceed observational constraints, unless the dark matter mass is very low. We shall also derive a very general bond on the dark matter annihilation cross section. By considering annihilation into all Standard Model particles, we show that the least detectable final states, namely neutrinos, define an upper bound on the total annihilation cross section. Calculating the cosmic diffuse neutrino signal, and comparing it to the measured terrestrial atmospheric neutrino background, we derive a robust limit that is much stronger than the unitarity bound in the most interesting mass range. We conclude that dark matter self-annihilation rates cannot be large enough to have a significant effect on the density profiles of dark matter halos.

The idea of light dark matter provides a plausible explanation for the observed 511 keV line emission from the galactic bulge. But the processes involved also emit the continuous spectrum of γ-rays. We present a detailed calculation of continuous spectrum for the decay model of light dark matter. Confrontation with the observed spectrum is challenging. We get the conservative mass bound m_LDM ≲ 20 MeV for the decay model, and find that better understanding is needed for the diffuse γ-rays from the galactic bulge in the energy range 20 keV – 20 MeV.

We report the study¹ on the thermal properties of unparticle, a scale invariant sector with a non-trivial infrared fixed point. Unparticle with scaling dimension has peculiar thermal properties due to its unique phase space structure. We find that the equation of state parameter , the ratio of pressure to energy density, is given by providing a new form of energy in our universe. In an expanding universe, the unparticle energy density evolves dramatically differently from that for photons, which makes it possible to have a large unparticle relic density today.

Spectroscopic observations of metal poor halo stars give an indication of a possible primordial plateau of ⁶Li abundance as a function of metallicity similar to that for ⁷Li. The inferred abundance of ⁶Li is ~1000 times larger than that predicted by standard big bang nucleosynthesis (BBN) for the baryon-to-photon ratio inferred from the WMAP data, and that of ⁷Li is about 3 times smaller than the prediction. We study a possible solution to both the problems of underproduction of ⁶Li and overproduction of ⁷Li in BBN. This solution involves a hypothetical massive, negatively-charged particle that would bind to the light nuclei produced in BBN. The particle gets bound to the existing nuclei after the usual BBN, and a second epoch of nucleosynthesis can occur among nuclei bound to the particles. We numerically carry out a fully dynamical BBN calculation, simultaneously solving the recombination and ionization processes of negatively-charged particles by normal and particle-bound nuclei as well as many possible nuclear reactions among them. It is confirmed that BBN in the presence of these hypothetical particles can solve the two Li abundance problems simultaneously.

We discuss the observation, analysis, and results of the first-year science operation of AMiBA, an interferometric experiment designed to study cosmology via the measurement of Cosmic Microwave Background (CMB). In 2007, we successfully observed 6 galaxy clusters (z < 0.33) through the Sunyaev-Zel'dovich effect. AMiBA is the first CMB interferometer operating at 86–102 GHz, currently with 7 close-packed antennas of 60 cm in diameter giving a synthesized resolution of around 6 arcminutes. An observing strategy with on-off-source modulation is used to remove the effects from electronic offset and ground pickup. Formalism of the analysis is given and preliminary science results are summarized. Tests for systematic effects are also addressed. We also discuss the expansion plan.

I first give an update on our study of the energy asymmetry given the proto-neutron star during the time when the neutrino sphere is near the surface of the proto-neutron star, at a time 10-20s, using the modified URCA process. With the magnetic field strong enough for a large fraction of the electrons produced with the anti-neutrinos to be in the lowest Landau level, we predict a pulsar velocity of 1.03 × 10⁻⁴(T/10¹⁰K)⁷km/s, which reaches 1000 km/s if T ≃ 9.96 × 10¹⁰K. Also, using the recent results of the MiniBoone study, with two sterile neutrinos, I give results for pulsar kicks during the first 10s.

The existence of a primordial magnetic field (PMF) would affect both the temperature and polarization anisotropies of the cosmic microwave background (CMB) and the formation of the large scale structure(LSS). It also provides a plausible explanation for the disparity between observations and theoretical fits to the CMB power spectrum and the LSS. Here we report on calculations of not only the numerical power spectrum of the PMF, but also the correlations between the PMF power spectrum and the primary curvature perturbations.

It is well-known that the universe was in a plasma state both before decoupling and after reionization. However, the conventional wisdom has been that the plasma effects are largely Debye-shielded and can thus be safely ignored when considering large scale evolutions. Recently we showed that large scale structure formation in the universe may actually be suppressed by the plasma collective effect. Indeed, observational data indicate that the conventional theoretical formula tends to overestimate the matter power spectrum at scales k > 1hMpc⁻¹. In this paper, we further develop our theory through a more thorough and general derivation of the Maxwell-Einstein-Boltzmann equation. In addition to baryon density perturbation post reionization, we apply this general formulation to investigate the possible plasma effect on CMB anisotropy. As expected, while the plasma effect does render an observable effect to the former, its impact on the latter is totally negligible.