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In a lattice QCD calculation with two light dynamical Chirally Improved (CI) quarks we determine ground state and some excited state masses in all four Lambda baryon channels 1/2^\pm and 3/2^\pm. We perform an infinite volume extrapolation and confirm the widely discussed Lambda(1405). We also analyze the amount of octet-singlet mixing, which is helpful in comparing states with the quark model.

We present a study of baryon ground states and low lying excitations of non-strange and strange baryons. The results are based on seven gauge field ensembles with two dynamical light Chirally Improved (CI) quarks corresponding to pion masses between 255 and 596 MeV and a strange valence quark with mass fixed by the Omega baryon. The lattice spacing varies between 0.1324 and 0.1398 fm. Given in lattice units, the bulk of our results are for size 16^3\times 32, for two ensembles with light pion masses (255 and 330 MeV) we also use 24^3\times 48 lattices and perform an infinite volume extrapolation. We derive energy levels for the spin 1/2 and 3/2 channels for both parities. In general, our results in the infinite volume limit compare well with experiment. We analyze the flavor symmetry content by identifying the singlet/octet/decuplet contributions of the resulting eigenstates. The ground states compositions agree with quark model expectations. In some cases the excited states, however, disagree and we discuss possible reasons., Comment: 22 pages, 27 figures

We simulate $K\ensuremath{\pi}$ scattering in $s$ wave and $p$ wave for both isospins $I=1/2$, $3/2$ using quark-antiquark and meson-meson interpolating fields. We extract the elastic phase shifts $\ensuremath{\delta}$ at several values of the $K\ensuremath{\pi}$ relative momenta. The resulting phases exhibit qualitative agreement with the experimental phases in all four channels. We express the $s$-wave phase shifts near threshold in terms of the scattering length and the effective range. Our $K\ensuremath{\pi}$ system has zero total momentum and is simulated on a single ensemble with two dynamical quarks, so results apply for ${m}_{\ensuremath{\pi}}\ensuremath{\simeq}266\text{ }\text{ }\mathrm{MeV}$ and ${m}_{K}\ensuremath{\simeq}552\text{ }\text{ }\mathrm{MeV}$ in our simulation. The backtracking contractions in both $I=1/2$ channels are handled by the use of Laplacian-Heavyside smeared quarks within the distillation method. Elastic phases are extracted from the energy levels using L\"uscher's relations. In all four channels, we observe the expected $K(n)\ensuremath{\pi}(\ensuremath{-}n)$ scattering states, which are shifted due to the interaction. In both attractive $I=1/2$ channels, we observe additional states which are related to resonances; we attribute them to ${K}_{0}^{*}(1430)$ in $s$ wave and ${K}^{*}(892)$, ${K}^{*}(1410)$ and ${K}^{*}(1680)$ in $p$ wave.

We systematically compare filtering methods used to extract topological excitations from lattice gauge configurations. We show that there is a strong correlation of the topological charge densities obtained by APE and Stout smearing. Furthermore, a first quantitative analysis of quenched and dynamical configurations reveals a crucial difference of their topological structure: the topological charge density is more fragmented, when dynamical quarks are present. This fact also implies that smearing has to be handled with great care, not to destroy these characteristic structures., Comment: 5 pages; talk given by F. Gruber at Confinement8, Mainz, Germany, September 1 - 6, 2008

The lowest eigenmodes of the Dirac operator are related to the dynamical breaking of the chiral symmetry in Quantum Chromodynamics (QCD). In our work we construct quark propagators which exclude a varying number of the lowest Dirac eigenmodes and study the influence thereof on meson correlators and the meson spectrum. That procedure partially restores the chiral symmetry (in the valence sector) and we observe degeneracies in the spectrum while confinement seems not to be affected.

We study hadron correlators upon artificial restoration of the spontaneously broken chiral symmetry. In a dynamical lattice simulation we remove the lowest lying eigenmodes of the Dirac operator from the valence quark propagators and study evolution of the hadron masses obtained. All mesons and baryons in our study, except for a pion, survive unbreaking the chiral symmetry and their exponential decay signals become essentially better. From the analysis of the observed spectroscopic patterns we conclude that confinement still persists while the chiral symmetry is restored. All hadrons fall into different chiral multiplets. The broken U(1)_A symmetry does not get restored upon unbreaking the chiral symmetry. We also observe signals of some higher symmetry that includes chiral symmetry as a subgroup. Finally, from comparison of the \Delta - N splitting before and after unbreaking of the chiral symmetry we conclude that both the color-magnetic and the flavor-spin quark-quark interactions are of equal importance., Comment: 12 pages, 14 figures; final version

In Quantum Chromodynamics (QCD) the eigenmodes of the Dirac operator with small absolute eigenvalues have a close relationship to the dynamical breaking of the chiral symmetry. In a simulation with two dynamical quarks, we study the behavior of meson propagators when removing increasingly more of those modes in the valence sector, thus partially removing effects of chiral symmetry breaking. We find that some of the symmetry aspects are restored (e.g., the masses of $\rho$ and $a_1$ approach each other) while confining properties persist., Comment: 5 pages, 5 figures (figure added, references updated)

It is possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark Fock component of a meson in the infrared, where mass is generated. Using the variational method and a set of interpolators that span a complete chiral basis we extract in a lattice QCD Monte Carlo simulation with two dynamical light quarks the orbital angular momentum and spin content of the rho-meson. We obtain in the infrared a simple 3S1 component as a leading component of the rho-meson with a small admixture of the 3D1 partial wave, in agreement with the SU(6) flavor-spin symmetry., 23 pages, 4 figures, 2 tables

We employ a variational basis with a number of $\bar{q}q$ and $\pi\pi$ lattice interpolating fields with quantum numbers of the $\rho$ resonance to extract the discrete energy spectrum in a finite volume. In the elastic region, this spectrum is related to the phase shift of the continuum scattering amplitude by L\"uscher's formula and the relation allows the extraction of resonance parameters from the spectrum calculation. The simulations are performed at three different total momenta of the coupled $\bar q q-\pi\pi$ system, which allows us to extract the p-wave scattering phase at five values of pion relative momenta near the resonance region. The effective range formula describes the phase-shift dependence nicely and we extract the resonance mass $m_\rho=792(7)(8)$ MeV and the coupling $g_{\rho\pi\pi}=5.13(20)$ at our $m_\pi\simeq 266 $MeV. The coupling $g_{\rho\pi\pi}$ is directly related to the width of the $\rho$ meson and our value is close to the value derived from the experimental width. The simulations are performed using dynamical gauge configurations with two mass-degenerate flavors of tree-level improved clover-Wilson fermions. Correlation functions are calculated using the recently proposed distillation method with Laplacian Heaviside (LapH) smearing of quarks, which enables flexible calculations, in many cases with unprecedented accuracy., Comment: 17 pages, 9 figures. This version contains an erratum at the end. The preferred choice of dispersion relation is affected. The main text is identical to arXiv:1105.5636v2

The excited isovector meson spectrum is explored using two chirally improved dynamical quarks. Seven ensembles, with pion masses down to \approx 250 MeV are discussed and used for extrapolations to the physical point. Strange mesons are investigated using partially quenched s-quarks. Using the variational method, we extract excited states in several channels and most of the results are in good agreement with experiment., Comment: 7 pages, 11 figures, talk given at the XXIX International Symposium on Lattice Field Theory - Lattice 2011, July 10-16 2011, Squaw Valley, Lake Tahoe, California

We study the one-component ${\ensuremath{\Phi}}^{4}$ model for four different lattice actions in the Gaussian limit and for the Ising model in the broken phase with a Monte Carlo simulation. Emphasis is put on the Euclidean invariance properties of the boson propagator. A measure of the violation of rotational symmetry is used to compare the regularization dependence of the triviality bound.

We study a simple 2-d model representing two fields with different mass and a 3-point coupling term. The phase shift in the resonating 2-particle channel is determined from the energy spectrum obtained in Monte Carlo simulations on finite lattices. Masses and wave function renormalization constants of the fields as well as mass and width of the resonance are determined and discussed. The representation of scattering states in terms of the considered operators is analysed., 24 p + 8 PS-figures, UNIGRAZ-UTP-04-05-92

We investigate whether the lightest scalar mesons {sigma} and {kappa} have a large tetraquark component qqqq, as is strongly supported by many phenomenological studies. A search for possible light tetraquark states with J{sup PC}=0{sup ++} and I=0,2,1/2,3/2 on the lattice is presented. We perform the two-flavor dynamical simulation with chirally improved quarks and the quenched simulation with overlap quarks, finding qualitative agreement between both results. The spectrum is determined using the generalized eigenvalue method with a number of tetraquark interpolators at the source and the sink, and we omit the disconnected contractions. The time dependence of the eigenvalues at the finite temporal extent of the lattice is explored also analytically. In all the channels, we unavoidably find the lowest scattering states {pi}(k){pi}(-k) or K(k){pi}(-k) with back-to-back momentum k=0,2{pi}/L,.... However, we find an additional light state in the I=0 and I=1/2 channels, which may be interpreted as the observed resonances {sigma} and {kappa} with a sizable tetraquark component. In the exotic repulsive channels I=2 and I=3/2, where no resonance is observed, we find no light state in addition to the scattering states.

Results of hadron spectroscopy with two dynamical mass-degenerate chirally improved quarks are presented. Three ensembles with pion masses of 322(5), 470(4) and 525(7) MeV, lattices of size 16^3 \times 32, and lattice spacings close to 0.15 fm are investigated. We discuss the possible appearance of scattering states, considering masses and eigenvectors. Partially quenched results in the scalar channel suggest the presence of a 2-particle state, however, in most channels we cannot identify them. Where available, we compare to results from quenched simulations using the same action., 7 pages, 9 figures, 1 table, talk given at the XXVIII International Symposium on Lattice Field Theory (Lattice 2010), June 14-19,2010, Villasimius, Sardinia, Italy

We present results of meson and baryon spectroscopy using the Chirally Improved Dirac operator on lattices of size 16**3 x 32 with two mass-degenerate light sea quarks. Three ensembles with pion masses of 322(5), 470(4) and 525(7) MeV and lattice spacings close to 0.15 fm are investigated. Results on ground and excited states for several channels are given, including spin two mesons and hadrons with strange valence quarks. The analysis of the states is done with the variational method, including two kinds of Gaussian sources and derivative sources. We obtain several ground states fairly precisely and find radial excitations in various channels. Excited baryon results seem to suffer from finite size effects, in particular at small pion masses. We discuss the possible appearance of scattering states in various channels, considering masses and eigenvectors. Partially quenched results in the scalar channel suggest the presence of a 2-particle state, however, in most channels we cannot identify them. Where available, we compare our results to results of quenched simulations using the same action., Comment: 27 pages, 29 figures, 11 tables

We address the question whether the lightest scalar mesons sigma and kappa are tetraquarks, as is strongly supported by many phenomenological studies. We present a search for possible light tetraquark states with J^PC=0^++ and I=0, 1/2, 3/2, 2 on the lattice. The spectrum is determined using the generalized eigenvalue method with a number of tetraquark interpolators at the source and the sink. In all the channels, we unavoidably find lowest scattering states pi(k)pi(-k) or K(k)pi(-k) with back-to-back momentum k=0,2*pi/L,.. . However, we find an additional light state in the I=0 and I=1/2 channels, which may be related to the observed resonances sigma and kappa with a strong tetraquark component. In the exotic repulsive channels I=2 and I=3/2, where no resonance is observed, we find no light state in addition to the scattering states., Comment: 7 pages, 4 figures, talk presented at The XXVII International Symposium on Lattice Field Theory, July 26-31, 2009, Peking University, Beijing, China

Inst. f. Theoret. Physik, Univ. Regensburg, Regensburg, GernmayE-mail:georg.engel@uni-graz.at, christof.gattringer@uni-graz.at,christian.lang@uni-graz.at, markus.limmer@uni-graz.at,daniel.mohler@uni-graz.at, andreas.schaefer@physik.uni-regensburg.deThe chirally improved (CI) fermion action allows us to obtain results for pion masses down to320 MeV on (in lattice units) comparatively small lattices with physical extent of 2.4 fm. We usedifferently smeared quarks sources to build sets of several interpolators. The variational methodthenleads to excellentgroundstate masses formost mesons andbaryons. Theexcitedstate signalsweaken in quality towards smaller quark masses. In particular the excited baryons come out toohigh.The XXVII International Symposium on Lattice Field Theory -LAT2009July 26-31 2009Peking University, Beijing, China

Lattice Quantum Chromodynamics (LQCD) is the most versatile and powerful method to investigate non-perturbative effects in strong interaction physics. In view of the much improved statistical accuracy the control of systematic uncertainties became the most important issue in recent years. The most severe problem is the implementation of chiral symmetry. The BGR collaboration works with two different Dirac operators, both having good chiral properties but are suited best for the analysis of different aspects of QCD: Chirally Improved (CI) fermions are especially well suited for the investigation of excited hadrons while Fixed-Point (FP) fermions are ideal for studies in the so-called e- and δ-regime.

It is tempting and seems to have become common to identify critical values of the hopping parameter κ with the radius of convergence of the expansion in κ. We argue that these two values differ in the strongly coupled lattice Schwinger model with Wilson fermions. We also determine the chiral condensate for all values of κ.

We couple two Ising fields with a three-point term in order to study resonance scattering in a two-dimensional field theory. We determine mass and width of the resonance from the energy spectrum obtained in Monte Carlo simulations on finite lattices; our results confirm recent predictions.

We study the eigenvalue spectrum of different lattice Dirac operators (staggered, fixed point, overlap) and discuss their dependence on the topological sectors. Although the model is 2D (the Schwinger model with massless fermions) our observations indicate possible problems in 4D applications. In particular misidentification of the smallest eigenvalues due to non-identification of the topological sector may hinder successful comparison with Random Matrix Theory (RMT)., Comment: LATTICE99(topology and confinement), Latex2e using espcrc2.sty, 3 pages, 3 figures

We present first results from dynamical Chirally Improved (CI) fermion simulations for the axial charge $G_A$ of various hadrons. We work with 16^3x32 lattices of spatial extent 2.4 fm and use the variational method with a suitable basis of Jacobi-smeared interpolators to suppress contaminations from excited states., 7 pages, talk given at the XXVII International Symposium on Lattice Field Theory, July 26-31 2009, Peking University, Beijing, China

In the last chapter we started the construction of QCD on the lattice. We discussed a particularly important feature of QCD, namely the self-interaction of gluons. This self-interaction makes pure gluodynamics, i.e., QCD without quarks, an interesting, highly nontrivial theory. Pure gluodynamics shows color confinement, an important property of full QCD. Since gluodynamics is much easier to handle than QCD with quarks, it is an important subject for studies of confinement and its underlying mechanisms.

Chiral symmetry and its spontaneous breaking are central properties of QCD with important phenomenological implications. They explain why pions have unexpectedly small masses and why we do not see degenerate masses for parity partners in the baryon sector. This important role of chiral symmetry and the mechanism of its breaking require that a reasonable lattice version of QCD has to implement chiral symmetry properly.

In our first look at QCD on the lattice in Chap.2 we have already announced that our formulation of lattice fermions has not reached its final form. In particular we still need to take into account the correct statistics. In the first section of this chapter we will show that the required Fermi statistics can be implemented by using anti-commuting numbers for the quark fields, so-called Grassmann numbers. We will discuss the rules for calculating with Grassmann numbers, and we will derive a few key formulas for Gaussian integrals with Grassmann numbers.

A basic simulation of pure SU(3) gauge theory is something that by now can be done already on a modern PC and certainly is a pedagogically valuable exercise. This section provides the techniques necessary for such a calculation. It also serves as an introduction to Monte Carlo simulations, although for the sake of having an easy-to-follow presentation, we concentrate on the simplest algorithms.

In Chap. 1 we derived the lattice path integral for a scalar field theory using the canonical approach for the quantization of the system. Subsequently, we changed our point of view and adopted the lattice path integral itself as a method of quantization. The steps involved are a lattice discretization of the classical Euclidean action and the construction of the measure for the integration over “all configurations” of the classical fields. In this chapter we begin with the implementation of these two steps for quantum chromodynamics.

The implementation of chiral symmetry on the lattice discussed in Chap. 7 was an unsolved puzzle for many years. The problem has continuously inspired the lattice community and led to a variety of formulations for fermions on the lattice. So far we have focused on two kinds of fermions in our presentation, Wilson-type and overlap fermions. Wilson fermions provide a simple robust and easy-to-use discretization, while overlap fermions implement chiral symmetry in the most transparent way.

When introducing the QCD action on the lattice we had to discretize the derivative terms that show up in the continuum action. It was pointed out then that any discretization, e.g., symmetric differences for the first derivative in the fermion action, gives rise to discretization effects. Typically the discretization effects are of (a) for fermions and of (a 2) for the gauge fields. These disappear only in the continuum limit when the lattice spacing it a is sent to zero. Performing the continuum limit is, however, a nontrivial task. As one decreases a, the number of lattice points has to increase, such that the physical volume remains constant (ideally one would first send the number of lattice points to infinity before sending a to zero). Thus in a numerical simulation one always works with finite a and the discretization errors have to be dealt with, e.g., by including them in the extrapolation to vanishing a.

Since the big bang the universe has cooled down substantially. Still, understanding QCD at high temperature and at high matter density is important for various reasons. One of them is obviously a better understanding of quarkand gluon matter shortly after the big bang and of the condensation of hadrons in the cooling process. Many objects in the universe like neutron stars supposedly have high enough density or temperature to expect that hadronic matter behaves differently compared to usual atoms. On earth very energetic collisions of heavy ions provide also possibilities to study matter under extreme conditions. Thus studying QCD at high temperature and density from first principles is a challenging task for the lattice approach.

The basic tool for quantizing fields on the lattice is the Euclidean path integral. Our first chapter is dedicated to the introduction of the path integral formalism and to its interpretation. In order to develop the idea without getting lost in technicalities we introduce the path integral for the simplest case, a scalar field theory. We derive and discuss the two key equations of lattice field theory.

We present recent results of our dynamical simulations with Chirally Improved fermions and report on new developments in the determination of excited light-quark meson states using interpolators constructed by applying covariant derivatives on Jacobi-smeared quark sources within the framework of the variational method., 7 pages, 5 figures; talk presented at the XXVI International Symposium on Lattice Field Theory, 14-19 July 2008, Williamsburg, VA, USA

The variational method allows one to study the mixing of interpolators with different chiral transformation properties in the non-perturbatively determined physical state. It is then possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark component of a meson in the infrared, where mass is generated. Using a unitary transformation from the chiral basis to the LSJ basis one may extract a partial wave content of a meson. We present results for the ground state of the rho-meson using quenched simulations as well as simulations with two dynamical quarks, all for lattice spacings close to 0.15 fm. We point out that these results indicate a simple 3S1-wave composition of the rho-meson in the infrared, like in the SU(6) flavor-spin quark model., 4 pages, 2 figures, 1 table; final version, in print at Phys. Rev. Lett

We study finite-size scaling of the temperature zeroes of the partition function for Ф 4 theory in four dimensions. The theory is simulated by Monte Carlo cluster methods and histograms are used to determine the partition function. The positions of the zeroes are obtained for lattices ranging from 8 4 to 24 4 . The scaling laws include logarithmic corrections for the bulk quantities and we succeed to identify them clearly, in agreement with our analytical prediction.

We determine the value of the chiral condensate for compact QED at β =0. The finite size analysis is based on large volume expansion of chiral perturbation theory. It is therefore possible to determine the infinite volume, m =0 result on lattices much smaller than the Goldstone correlation length.

We study the eigenvalues of Dirac operators in QCD with two mass degenerate dynamical fermions. The gauge configurations have been obtained with HMC and the so-called Chirally Improved fermionic action. We compare eigenvalues obtained for the overlap Dirac operator on these configurations with those for the Chirally Improved (CI) operator (studied earlier). Results of Random Matrix Theory allow us to determine the chiral condensate.

We simulate two dynamical, mass degenerate light quarks on 16^3x32 lattices with a spatial extent of 2.4 fm using the Chirally Improved Dirac operator. The simulation method, the implementation of the action and signals of equilibration are discussed in detail. Based on the eigenvalues of the Dirac operator we discuss some qualitative features of our approach. Results for ground state masses of pseudoscalar and vector mesons as well as for the nucleon and delta baryons are presented., Comment: 26 pages, 17 figures, 10 tables

In this work we study the predominantly orbital and radial excitations of hadrons containing a single heavy quark. We present meson and baryon mass splittings and ratios of meson decay constants (e.g., $f_{B_s}/f_B$ and $f_{B_s'}/f_{B_s}$) resulting from quenched and dynamical two-flavor configurations. Light quarks are simulated using the chirally improved (CI) lattice Dirac operator at valence masses as light as $M_\pi \approx 350$ MeV. The heavy quark is approximated by a static propagator, appropriate for the $b$ quark on our lattices ($1/a \sim 1-2$ GeV). We also include some preliminary calculations of the $O(1/m_Q^{})$ kinetic corrections to the states, showing, in the process, a viable way of applying the variational method to three-point functions involving excited states. We compare our results with recent experimental findings., Comment: 23 pages, 18 figures, 17 tables; slight title change (Ed. killjoy); reference added; version to appear in Phys Rev D

Determining the hadron spectrum and hadron properties beyond the ground states is a challenge in lattice QCD. Most of these results have been in the quenched approximation but now we are entering the dynamical era. I review some of the ideas and methods of the lattice approach, concentrating on a few examples and on results obtained for Chirally Improved (CI) fermions., 18 pages, 12 figures, 1 table; Notes based on a lecture at the Int. School of Nuclear Physics, 29th Course, 16-24. Sept. 2007, Erice/Sicily, "Quarks in Hadrons and Nuclei"; minor modifications

It is commonly agreed that accounts receivable (AR) can be a source of financial difficulty for firms when they are not efficiently managed and are underperforming. Experience across multiple industries shows that effective management of AR and overall financial performance of firms are positively correlated. In this paper we address the problem of reducing outstanding receivables through improvements in the collections strategy. Specifically, we demonstrate how supervised learning can be used to build models for predicting the payment outcomes of newly-created invoices, thus enabling customized collection actions tailored for each invoice or customer. Our models can predict with high accuracy if an invoice will be paid on time or not and can provide estimates of the magnitude of the delay. We illustrate our techniques in the context of transaction data from multiple firms.

Database workloads seldom remain static. A system tuned by an expert for the current environment, might not always remain optimal. To deal with this situation, database systems have been incorporating self tuning features. An important component is self tuning memory or bufferpools. These often work on a feedback loop and take some time to converge to an optimal state. T)\c transition to the optimal state could be accelerated if future access patterns could be taken into account when making decisions on the bufferpool size. In this paper, we describe a caching algorithm for scans on bufferpools. which keeps track of ongoing scans and the state of each scan. T)\e proposed algorithm results in a better hit ratio and. more importantly, provides a way to predict future access patterns. This property is beneficial for providing feedback to a self-tuning memory controller to make better allocation decisions.

We present results for masses of light mesons obtained with the variational method using an enhanced basis of interpolating field operators with different quark smearings. The interpolators are constructed from Jacobi-smeared quarks of a Gaussian type as well as from derivative quark sources obtained by a covariant derivative acting on the Gaussian sources. For our analysis we use quenched gauge configurations with Chirally Improved quarks and the Luescher-Weisz gauge action on a 16^3 x 32 lattice with a = 0.148 fm. We discuss the influence of derivative sources on the overlap with excited states., Comment: 7 pages, Presented at the XXV International Symposium on Lattice Field Theory, July 30 - August 4 2007, Regensburg, Germany

XML documents are often represented as DOM structures or trees. In some instances, due to the complexity of queries, XPath queries are better evaluated by traversing these structures rather than using summarization indexes. A requirement for the optimization of document navigation, is to efficiently decrease the number of traversed nodes. The optimization task is more difficult when the query framework allows a syntax that enlarges the search space, such as wildcards and descendant queries. To reduce the overhead of query processing, many database systems supporting XML rely on indexes. Such indexes are typically not able to adapt to memory restrictions or workload changes. A secondary data structure that uses little storage space and tunes itself to address hot spots in processing, can therefore be beneficial. In this paper, we propose a first method for creating, using, and maintaining selective signatures called hints to aid in the navigation of XML documents. Hints form a flexible data structure for pruning the search space, that can be used on its own or it can complement existing indexes. The amount of hints used is variable, and it depends on the storage limitation set a priori, and on the efficiency of the hints. Our experiments show that hints can improve the efficiency of navigational XML query processing by a large margin while using only little extra memory.

Results for Monte Carlo calculations of the electromagnetic vector and scalar form factors of the pion in a quenched simulation are presented. We work with two different lattice volumes up to a spatial size of 2.4 fm at a lattice spacing of 0.148 fm. The pion form factors in the space-like region are determined for pion masses down to 340 MeV., REVTeX 4, 8 pages, 9 figures, 4 tables; final version

We present results for masses of excited baryons from a quenched calculation with Chirally Improved quarks at pion masses down to 350 MeV. Our analysis of the correlators is based on the variational method. In order to provide a large basis set for spanning the physical states, we use interpolators with different Dirac structures and Jacobi smeared quark sources of different width. Our spectroscopy results for a wide range of ground state and excited baryons are discussed., 11 pages, 8 figures

We compare the eigenvalue spectra of the Dirac operator from a simulation with two mass degenerate dynamical chirally improved fermions with Random Matrix Theory. Comparisons with distribution of k-th eigenvalues (k=1,2) in fixed topological sectors (nu=0,1) are carried out using the Kolmogorov-Smirnov test. The eigenvalue distributions are well described by the RMT predictions. The match allows us to read off the quark condensate in the chiral limit directly. Correcting for finite size and renormalization we obtain a mean value of -(276 (11)(16) MeV)**3 in the MS-bar scheme., Comment: 8 pages, 2 figures, Final version. To be published