2427640
Non-Abelian Vortex and Confinement
We discuss general properties and possible types of magnetic vortices in non-Abelian gauge theories (we consider here G = SU(N), SO(N), USp(2N)) in the Higgs phase. The sources of such vortices carry "fractional" quantum numbers such as Zn charge (for SU(N)), but also full non-Abelian charges of the dual gauge group. If such a model emerges as an effective dual magnetic theory of the fundamental (electric) theory, the non-Abelian vortices can provide for the mechanism of quark confinement in the latter.
119485873
A simple algorithm for QCD jets
Abstract A proposal is made, giving multiparticle (parton) spectra inside quark and gluon jets in terms of the tree diagrams of an effective field theory. The resulting “jet calculus” satisfies many consistency checks. A first sample of applications is given.
16105331
Nonabelian superconductors: vortices and confinement in N=2 SQCD
We study nonabelian vortices (flux tubes) in SU(N) gauge theories, which are 
responsible for the confinement of (nonabelian) magnetic monopoles. In 
particular a detailed analysis is given of ${\cal N}=2$ SQCD with gauge group 
SU(3) deformed by a small adjoint chiral multiplet mass. Tuning the bare quark 
masses (which we take to be large) to a common value $m$, we consider a 
particular vacuum of this theory in which an SU(2) subgroup of the gauge group 
remains unbroken. We consider $5 \ge N_f \ge 4$ flavors so that the SU(2) 
sub-sector remains non asymptotically free: the vortices carrying nonabelian 
fluxes may be reliably studied in a semi-classical regime. We show that the 
vortices indeed acquire exact zero modes which generate global rotations of the 
flux in an $SU(2)_{C+F}$ group. We study an effective world-sheet theory of 
these orientational zero modes which reduces to an ${\cal N}=2$ O(3) sigma 
model in (1+1) dimensions. Mirror symmetry then teaches us that the dual SU(2) 
group is not dynamically broken.
123003167
Generation of mass hierarchies and gravitational instanton-induced supersymmetry breaking
Consequences of supersymmetry breaking by gravitational instantons are studied in the context of N = 1 supergravity models. In particular, models containing an additional term, proportional to the Euler characteristics density of the spacetime manifold, are shown to lead to a large hierarchy of masses, with the supersymmetry breaking mass scale much smaller than the Planck mass. Possible mechanisms of mass generation for gauge fermions, matter scalars and matter fermions are discussed. Models of this type can arise as a low-energy approximation to superstring models. Our analysis suggests the existence and importance of those nonperturbative effects in the underlying string theories that correspond to the Yang-Mills and gravitational instantons of low-energy effective field theories.
1333458
Non-Abelian confinement near nontrivial conformal vacua
Abstract We discuss some aspects of confinement and dynamical symmetry breaking in the so-called non-Abelian Argyres–Douglas vacua, which occur very generally in supersymmetric theories. These systems are characterized by strongly-coupled non-Abelian monopoles and dyons; confinement and dynamical symmetry breaking are caused by the condensation of monopole composites, rather than by condensation of single weakly-coupled monopoles. In general, there are strong constraints on which kind of monopoles can appear as the infrared degrees of freedom, related to the proper realization of the global symmetry of the theory. Drawing analogies to some of the phenomena found here, we make a speculation on the ground state of the standard QCD.
121970658
A Simple Algorithm for QCD Jets-An Introduction to Jet Calculus
A new, simple algorithm, recently proposed for QCD jets, is discussed. It allows to compute multiparton distributions inside QCD (q- or g-) jets, within the leading logarithmic approximation. Some of its applications are given.
119248886
Subaru Spectroscopy of SDSS-II Supernovae
The Sloan Digital Sky Survey II (SDSS-II) Supernova Survey discovered Type Ia supernovae (SNe Ia) in an almost unexplored intermediate redshift range of $0.05 < z < 0.4$ and provided densely sampled multi-color light curves for SN candidates. Followup spectroscopy of this survey was carried out with the Subaru telescope and spectra of 71 SN Ia candidates were obtained. One spectrum was observed per candidate except for a peculiar variable. This paper presents the method for processing these spectra. The observed wavelength ranges of our spectra are 4000 to 9000 {\AA} for Year 2005 and 3600 to 9000 {\AA} for Year 2006. Most SN Ia spectra have signal to noise ratios (S/N) between 4 and 10 per 2 {\AA} averaged over the entire wavelength region. We developed a new code to extract the SN spectral component from spectra contaminated by the host galaxy. Of 71 SN Ia candidates, 59 are identified as normal SNe Ia and 3 are peculiar SNe Ia. The range of spectral phases varies from -7 days to +30 days from maximum brightness. There are also 7 SNe II, 1 possible hypernova and 1 AGN.
118546402
Line Profiles of Intermediate Redshift Type Ia Supernovae
We present the temporal evolution of line profiles ranging from near ultraviolet to optical wavelengths by analyzing 59 Subaru telescope spectra of normal Type Ia Supernovae (SNe Ia) in the intermediate redshift range (0.05 < z < 0.4) discovered by the Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. We derive line velocities, peak wavelengths and pseudo-equivalent widths (pEWs) of these lines. Additionally, we compare the line profiles around the date of maximum brightness with those from their nearby counterparts. We find that line profiles represented by their velocities and pEWs for intermediate redshift SNe Ia are consistent with their nearby counterparts within 2 $\sigma$. These findings support the picture that SNe Ia are a "standard" candle for the intermediate redshift range as has been shown between SNe Ia at nearby and high redshifts. There is a hint that the "MgII \lambda 4300" pEW distribution for intermediate redshift SNe Ia is larger than for the nearby sample, which could be interpreted as a difference in the progenitor abundance.
118626595
A MISMATCH IN THE ULTRAVIOLET SPECTRA BETWEEN LOW-REDSHIFT AND INTERMEDIATE-REDSHIFT TYPE Ia SUPERNOVAE AS A POSSIBLE SYSTEMATIC UNCERTAINTY FOR SUPERNOVA COSMOLOGY
We present Keck high-quality rest-frame ultraviolet (UV) through optical spectra of 21 Type Ia supernovae (SNe?Ia) in the redshift range 0.11 ? z ? 0.37 and a mean redshift of 0.22 that were discovered during the Sloan Digital Sky Survey-II (SDSS-II) SN Survey. Using the broadband photometry of the SDSS survey, we are able to reconstruct the SN host-galaxy spectral energy distributions (SEDs), allowing for a correction for the host-galaxy contamination in the SN Ia spectra. Comparison of composite spectra constructed from a subsample of 17 high-quality spectra to those created from a low-redshift sample with otherwise similar properties shows that the Keck/SDSS SNe?Ia have, on average, extremely similar rest-frame optical spectra but show a UV flux excess. This observation is confirmed by comparing synthesized broadband colors of the individual spectra, showing a difference in mean colors at the 2.4?-4.4? level for various UV colors. We further see a slight difference in the UV spectral shape between SNe with low-mass and high-mass host galaxies. Additionally, we detect a relationship between the flux ratio at 2770 and 2900 ? and peak luminosity that differs from that observed at low redshift. We find that changing the UV SED of an SN Ia within the observed dispersion can change the inferred distance moduli by ~0.1?mag. This effect only occurs when the data probe the rest-frame UV. We suggest that this discrepancy could be due to differences in the host-galaxy population of the two SN samples or to small-sample statistics.
17597272
The Sloan Digital Sky Survey-II Photometry and Supernova IA Light Curves from the 2005 Data
We present ugriz light curves for 146 spectroscopically-confirmed or spectroscopically-probable Type Ia supernovae (SNe) from the 2005 season of the Sloan Digital Sky Survey-II Supernova (SN) survey. The light curves have been constructed using a photometric technique that we call scene modeling, which is described in detail here; the major feature is that SN brightnesses are extracted from a stack of images without spatial resampling or convolution of the image data. This procedure produces accurate photometry along with accurate estimates of the statistical uncertainty, and can be used to derive photometry taken with multiple telescopes. We discuss various tests of this technique that demonstrate its capabilities. We also describe the methodology used for the calibration of the photometry, and present calibrated magnitudes and fluxes for all of the spectroscopic SNe Ia from the 2005 season.
119204401
First-year Sloan Digital Sky Survey-II supernova results: consistency and constraints with other intermediate-redshift data sets
ABSTRACT We present an analysis of the luminosity distances of Type Ia Supernovae (SNe) from the Sloan Digital Sky Survey-II (SDSS-II) SN Survey in conjunction with other intermediate-redshift (z 97 per cent level from this single data set. We find good agreement between the SN and BAO distance measurements, both consistent with a Λ-dominated cold dark matter cosmology, as demonstrated through an analysis of the distance duality relationship between the luminosity (dL) and angular diameter (dA) distance measures. We then use these data to estimate w within this restricted redshift range (z < 0.4). Our most stringent result comes from the combination of all our intermediate-redshift data (SDSS-II SNe, BAO, ISW and redshift-space distortions), giving w = -0.81+0.16-0.18 (stat) +/- 0.15 (sys) and ΩM = 0.22+0.09-0.08 assuming a flat universe. This value of w and associated errors only change slightly if curvature is allowed to vary, consistent with constraints from the cosmic microwave background. We also consider more limited combinations of the geometrical (SN, BAO) and dynamical (ISW, redshift-space distortions) probes.