WorldWideScience

Sample records for baryon mass spectra

  1. Excited mass spectra of Σ+c baryon

    International Nuclear Information System (INIS)

    Baryons are strongly interacting fermions made up of three quarks. Recently, many of single charm baryons are discovered by different colliders like CLEO, Belle, BABAR, etc. Among different phenomenological Quark models, we practise on Hypercentral Constituent Quark Model (hCQM) with coulomb plus power potential. The methodology of single charmed Baryon Σ+c is derived in the paper. Our predictions for charmed baryon masses are matched with other theoretical prediction as well as known experimental data. The obtained results are used for constructing the heavy baryon Regge trajectories in the (nr, M2)

  2. Mass spectra of doubly heavy baryons in the relativistic quark model

    OpenAIRE

    Ebert, D; Faustov, R. N.; Galkin, V. O.; Martynenko, A. P.

    2002-01-01

    Mass spectra of baryons consisting of two heavy (b or c) and one light quarks are calculated in the framework of the relativistic quark model. The light quark-heavy diquark structure of the baryon is assumed. Under this assumption the ground and excited states of both the diquark and quark-diquark bound system are considered. The quark-diquark potential is constructed. The light quark is treated completely relativistically, while the expansion in the inverse heavy quark mass is used revealing...

  3. Excited State Mass spectra of doubly heavy baryons $\\Omega_{cc}$, $\\Omega_{bb}$ and $\\Omega_{bc}$

    CERN Document Server

    Shah, Zalak; Rai, Ajay Kumar

    2016-01-01

    We discuss the mass spectrum of $\\Omega$ baryon with two heavy quarks and one light quark (\\textit{ccs, bbs and bcs}). The main goal of the paper is to calculate the ground state masses and after that, the positive and negative parity excited states masses are also obtained within a Hypercentral Constituent quark model, using coulomb plus linear potential framework. We also added first order correction to the potential. The mass spectra upto 5S for radial excited states and 1P-5P, 1D-4D and 1F-2F states for orbital excited states are computed for $\\Omega_{cc}$, $\\Omega_{bb}$ and $\\Omega_{bc}$ baryons. Our obtained results are compared with other theoretical predictions which could be a useful complementary tool for the interpretation of experimentaly unknown heavy baryon spectra. The Regge trajectory is constructed in both ($n_r$, $M^{2}$) and ($J$, $M^{2}$) planes for $\\Omega_{cc}$,$\\Omega_{bb}$ and $\\Omega_{bc}$ baryons and their slopes and intercepts are also determined. Magnetic moments of doubly heavy $\\...

  4. Rotational Spectra of the Baryons and Mesons

    CERN Document Server

    Akers, D

    2003-01-01

    An investigation of the rotational spectra of baryons and mesons is conducted. Diakonov, Petrov and Polyakov claimed that all light baryons are rotational excitations. A study of the history of particle physics indicates that the ideas of rotational spectra can be originally attributed to a constituent-quark (CQ) model as proposed by Mac Gregor. Later research advanced spin-orbit splitting in a deformed model as suggested by Bhaduri and others. In the present work, we show from current data that the rotational spectra of baryons and mesons are in agreement with the original claims of Mac Gregor: namely, the values for the rotational energies Erot of particles merge with those of nuclear rotational bands in light nuclei. It is also shown that particles of different isotopic spins are separated in mass by a 70 MeV quantum, which is related to the SU(3) decuplet mass spacing as originally proposed by Gell-Mann.

  5. R-baryon masses

    Energy Technology Data Exchange (ETDEWEB)

    Buccella, F.; Farrar, G.R.; Rutgers - the State Univ., New Brunswick, NJ; Pugliese, A.

    1985-04-04

    The MIT bag model is used to calculate masses of (R-)baryons, composed of three quarks and a gluino. If the gluino mass is small, the lightest of these, a flavor singlet, could be long-lived or even absolutely stable. The next lighest, the R-nucleons, probably have only weak decays, while all others are likely to decay strongly. This physical picture is not ruled out experimentally. (orig.).

  6. R-baryon masses

    Energy Technology Data Exchange (ETDEWEB)

    Buccella, F.; Farrar, G.R.; Pugliese, A.

    1985-04-04

    The MIT bag model is used to calculate masses of (R-)baryons, composed of three quarks and a gluino. If the gluino mass is small, the lightest of these, a flavor singlet, could be long-lived or even absolutely stable. The next lighest, the R-nucleons, probably have only weak decays, while all others are likely to decay strongly. This physical picture is not ruled out experimentally.

  7. R-baryon masses

    International Nuclear Information System (INIS)

    The MIT bag model is used to calculate masses of (R-)baryons, composed of three quarks and a gluino. If the gluino mass is small, the lightest of these, a flavor singlet, could be long-lived or even absolutely stable. The next lighest, the R-nucleons, probably have only weak decays, while all others are likely to decay strongly. This physical picture is not ruled out experimentally. (orig.)

  8. Decay and spectra of baryons especially beauty baryons

    Science.gov (United States)

    Kalman, C. S.

    1996-06-01

    Masses and decays of the baryons are considered. The entire spectroscopy of baryons containing u,d,s,c and b quarks is calculated using the five quark masses and only four additional parameters describing the potential between the baryons. This potential is taken to be a short-range Coulomb potential together with a long-range linear potential modified by a harmonic-oscillator potential. Decays are studied using the quark pair creation model of Le Yaouanc et. al. The pair strength γ is replaced by kγ . This and the meson radius are the only parameters used in the calculation of the decays. Overall, we have a useful model, employing a small number of parameters, yet capable of yielding a description of the baryons in good accord with experimental data.

  9. Understanding the baryon and meson spectra

    Energy Technology Data Exchange (ETDEWEB)

    Pennington, Michael R. [JLAB

    2013-10-01

    A brief overview is given of what we know of the baryon and meson spectra, with a focus on what are the key internal degrees of freedom and how these relate to strong coupling QCD. The challenges, experimental, theoretical and phenomenological, for the future are outlined, with particular reference to a program at Jefferson Lab to extract hadronic states in which glue unambiguously contributes to their quantum numbers.

  10. Baryonic masses based on the NJL model

    International Nuclear Information System (INIS)

    We employ the Nambu-Jona-Lasinio model to determine the vacuum pressure on the quarks in a baryon and hence their density inside. Then we estimate the baryonic masses by implementing the local density approximation for the mean-field quark energies obtained in a uniform and isotropic system. We obtain a fair agreement with the experimental masses. (orig.)

  11. Decuplet baryon masses in covariant baryon chiral perturbation theory

    OpenAIRE

    Ren, Xiu-Lei; Geng, Li-Sheng; Meng, Jie

    2013-01-01

    We present an analysis of the lowest-lying decuplet baryon masses in the covariant baryon chiral perturbation theory with the extended-on-mass-shell scheme up to next-to-next-to-next-to-leading order. In order to determine the $14$ low-energy constants, we perform a simultaneous fit of the $n_f=2+1$ lattice QCD data from the PACS-CS, QCDSF-UKQCD, and HSC Collaborations, taking finite-volume corrections into account self-consistently. We show that up to next-to-next-to-next-to-leading order on...

  12. Baryon masses with dynamical twisted mass fermions

    CERN Document Server

    Alexandrou, C; Koutsou, G; Baron, R; Guichon, P; Brinet, M; Carbonell, J; Drach, V; Liu, Z; Pène, O; Urbach, C

    2007-01-01

    We present results on the mass of the nucleon and the $\\Delta$ using two dynamical degenerate twisted mass quarks. The evaluation is performed at four quark masses corresponding to a pion mass in the range of 690-300 MeV on lattices of size 2.1 fm and 2.7 fm. We check for cutoff effects by evaluating these baryon masses on lattices of spatial size 2.1 fm with lattice spacings $a(\\beta=3.9)=0.0855(6)$ fm and $a(\\beta=4.05)=0.0666(6)$ fm, determined from the pion sector and find them to be within our statistical errors. Lattice results are extrapolated to the physical limit using continuum chiral perturbation theory. The nucleon mass at the physical point provides a determination of the lattice spacing. Using heavy baryon chiral perturbation theory at ${\\cal O}(p^3)$ we find $a(\\beta=3.9)=0.0879(12)$ fm, with a systematic error due to the chiral extrapolation estimated to be about the same as the statistical error. This value of the lattice spacing is in good agreement with the value determined from the pion se...

  13. Octet-baryon masses in finite space

    OpenAIRE

    Ren, Xiu-Lei; Geng, Lisheng; Meng, Jie

    2012-01-01

    We report on a recent study of finite-volume effects on the lowest-lying octet baryon masses using the covariant baryon chiral perturbation theory up to next-to-leading order by analysing the latest $n_f = 2 + 1$ lattice QCD results from the NPLQCD Collaboration.

  14. Baryon Mass in medium with Holographic QCD

    CERN Document Server

    Seo, Yunseok

    2008-01-01

    We study the baryon vertex (BV) in the presence of medium using DBI action and the force balance condition between BV and the probe branes. We note that a stable BV configuration exists only in some of the confining backgrounds. For the system of finite density, the issue is whether there is a canonical definition for the baryon mass in the medium. In this work, we define it as the energy of the deformed BV satisfying the force balance condition (FBC) with the probe brane. With FBC, lengths of the strings attached to the BV tend to be zero while the compact branes are enlongated to mimic the string. We attribute the deformation energy of the probe brane to the baryon-baryon interaction. We show that for a system with heavy quarks the baryon mass drops monotonically as a function of density while it has minimum in case of light quark system.

  15. Calculation of baryon masses in quantum chromodynamics

    International Nuclear Information System (INIS)

    The polarization operator of quark currents with the baryon quantum numbers is considered in quantum chromodynamics. The non-zero mean vacuum of the field operator products are taken into account. The sum rules are obtained assuming that in the virtuality region approximately 1 GeV, among the mean vacuum values violating the chiral invariance, the most important is . Saturating these sum rules by the lowest baryonic states one is able to calculate the masses of the isobar Δ and nucleon N, Msub(Δ) 1.4 GeV, Msub(N) = 1 GeV, up to 15 % through the known value . The mass splitting in the baryonic decuplet Msub(Σ*) - Msub(Δ) = 125 MeV is calculated in the first order in the current strange quark mass msub(s) = 150 MeV. Certain results for that baryonic resonances have been obtained

  16. Effect of negative energy component on baryon spectra

    International Nuclear Information System (INIS)

    Employing instantaneous Bethe-Salpeter equation and taking into account the confection of negative energy component of Dirac spinor to one-gluon exchange interaction, the calculation of the Δ, N baryon spectra is carried out. We find that the effect changes the potential parameters significantly, but leaves the global structures of spectrum almost untouched. (author)

  17. Fingerprint of a QCD string in baryon spectra

    Energy Technology Data Exchange (ETDEWEB)

    Kirchbach, M. [Escuela de Fisica, Universidad Autonoma de Zacatecas, A.P. C-600, 98062 Zacatecas (Mexico)

    2001-07-01

    Multi-spin valued states of the Rarita-Schwinger type (k/2, k/2) x encircled [(1/2, O) + encircled (0,1/2)] with k = 1, 3, and 5 are found to be realized in the excitation spectra of the light-quark baryons. We conjecture that the above multi-resonance clusters may take their origin from a QCD string described by means of a linear action. (Author)

  18. Isospin breaking in octet baryon mass splittings

    Energy Technology Data Exchange (ETDEWEB)

    Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Najjar, J. [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe, Hyogo (Japan); Pleiter, D. [Forschungszentrum Juelich (Germany). Juelich Supercomputer Centre; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics

    2012-06-15

    Using an SU(3) flavour symmetry breaking expansion in the quark mass, we determine the QCD component of the nucleon, Sigma and Xi mass splittings of the baryon octet due to up-down (and strange) quark mass differences in terms of the kaon mass splitting. Provided the average quark mass is kept constant, the expansion coefficients in our procedure can be determined from computationally cheaper simulations with mass degenerate sea quarks and partially quenched valence quarks. Both the linear and quadratic terms in the SU(3) flavour symmetry breaking expansion are considered; it is found that the quadratic terms only change the result by a few percent, indicating that the expansion is highly convergent.

  19. Isospin breaking in octet baryon mass splittings

    International Nuclear Information System (INIS)

    Using an SU(3) flavour symmetry breaking expansion in the quark mass, we determine the QCD component of the nucleon, Sigma and Xi mass splittings of the baryon octet due to up-down (and strange) quark mass differences in terms of the kaon mass splitting. Provided the average quark mass is kept constant, the expansion coefficients in our procedure can be determined from computationally cheaper simulations with mass degenerate sea quarks and partially quenched valence quarks. Both the linear and quadratic terms in the SU(3) flavour symmetry breaking expansion are considered; it is found that the quadratic terms only change the result by a few percent, indicating that the expansion is highly convergent.

  20. Virtual decuplet effects on octet baryon masses in covariant baryon chiral perturbation theory

    OpenAIRE

    Ren, Xiu-Lei; Geng, Lisheng; Meng, Jie; Toki, Hiroshi

    2013-01-01

    We extend a previous analysis of the lowest-lying octet baryon masses in covariant baryon chiral perturbation theory (ChPT) by explicitly taking into account the contribution of the virtual decuplet baryons. Up to next-to-next-to-next-to-leading order (N$^3$LO), the effects of these heavier degrees of freedom are systematically studied. Their effects on the light-quark mass dependence of the octet baryon masses are shown to be relatively small and can be absorbed by the available low-energy c...

  1. Dynamical twisted mass fermions and baryon spectroscopy

    International Nuclear Information System (INIS)

    The aim of this work is an ab initio computation of the baryon masses starting from quantum chromodynamics (QCD). This theory describes the interaction between quarks and gluons and has been established at high energy thanks to one of its fundamental properties: the asymptotic freedom. This property predicts that the running coupling constant tends to zero at high energy and thus that perturbative expansions in the coupling constant are justified in this regime. On the contrary the low energy dynamics can only be understood in terms of a non perturbative approach. To date, the only known method that allows the computation of observables in this regime together with a control of its systematic effects is called lattice QCD. It consists in formulating the theory on an Euclidean space-time and to evaluating numerically suitable functional integrals. First chapter is an introduction to the QCD in the continuum and on a discrete space time. The chapter 2 describes the formalism of maximally twisted fermions used in the European Twisted Mass (ETM) collaboration. The chapter 3 deals with the techniques needed to build hadronic correlator starting from gauge configuration. We then discuss how we determine hadron masses and their statistical errors. The numerical estimation of functional integral is explained in chapter 4. It is stressed that it requires sophisticated algorithm and massive parallel computing on Blue-Gene type architecture. Gauge configuration production is an important part of the work realized during my Ph.D. Chapter 5 is a critical review on chiral perturbation theory in the baryon sector. The two last chapter are devoted to the analysis in the light and strange baryon sector. Systematics and chiral extrapolation are extensively discussed. (author)

  2. Baryon Production at LHC and Very High Energy Cosmic Ray Spectra

    CERN Document Server

    Piskounova, Olga I

    2015-01-01

    The spectra of baryons at LHC can explain the features of the proton spectra in cosmic rays (CR). It seems important to study all baryon data that are available from collider experiments in wide range of energies. Transverse momentum spectra of baryons from RHIC ($\\sqrt(s)$=62 and 200 GeV) and from LHC ($\\sqrt(s)$=0.9 and 7 TeV) have been considered. It is seen that the slope of distributions at low $p_T$'s is changing with energy. The QGSM fit of these spectra gives the average transverse momenta which behave as $s^{0.06}$ that is similar to the previously observed behavior of $\\Lambda^0$ hyperon spectra. The change in average transverse momenta that are slowly growing in VHE hadron interactions at CR detectors cannot cause the "knee" in measured cosmic ray proton spectra. In addition, the available data on heavy quark hadron production from LHC-b at $\\sqrt{s}$=7 TeV were also studied. The preliminary dependence of hadron average transverse momenta on their masses at LHC energy is presented. The possible sou...

  3. A direct measurement of the baryonic mass function of galaxies & implications for the galactic baryon fraction

    CERN Document Server

    Papastergis, Emmanouil; Huang, Shan; Giovanelli, Riccardo; Haynes, Martha P

    2012-01-01

    We use both an HI-selected and an optically-selected galaxy sample to directly measure the abundance of galaxies as a function of their "baryonic" mass (stars + atomic gas). Stellar masses are calculated based on optical data from the Sloan Digital Sky Survey (SDSS) and atomic gas masses are calculated using atomic hydrogen (HI) emission line data from the Arecibo Legacy Fast ALFA (ALFALFA) survey. By using the technique of abundance matching, we combine the measured baryonic function (BMF) of galaxies with the dark matter halo mass function in a LCDM universe, in order to determine the galactic baryon fraction as a function of host halo mass. We find that the baryon fraction of low-mass halos is much smaller than the cosmic value, even when atomic gas is taken into account. We find that the galactic baryon deficit increases monotonically with decreasing halo mass, in contrast with previous studies which suggested an approximately constant baryon fraction at the low-mass end. We argue that the observed baryon...

  4. Finite-volume effects on octet-baryon masses in covariant baryon chiral perturbation theory

    OpenAIRE

    Geng, Li-Sheng; Ren, Xiu-Lei; Martin-Camalich, J.; Weise, W.

    2011-01-01

    We study finite-volume effects on the masses of the ground-state octet baryons using covariant baryon chiral perturbation theory (ChPT) up to next-to-leading order by analyzing the latest $n_f=2+1$ lattice Quantum ChromoDynamics (LQCD) results from the NPLQCD collaboration. Contributions of virtual decuplet baryons are taken into account using the "consistent" coupling scheme. We compare our results with those obtained from heavy baryon ChPT and show that, although both approaches can describ...

  5. Octet baryon masses and sigma terms in covariant baryon chiral perturbation theory

    OpenAIRE

    Ren, Xiu-Lei; Geng, Li-Sheng; Meng, Jie

    2015-01-01

    We report on a recent study of the ground-state octet baryon masses and sigma terms in covariant baryon chiral perturbation theory with the extended-on-mass-shell scheme up to next-to-next-to-next-to-leading order. To take into account lattice QCD artifacts, the finite-volume corrections and finite lattice spacing discretization effects are carefully examined. We performed a simultaneous fit of all the $n_f = 2+1$ lattice octet baryon masses and found that the various lattice simulations are ...

  6. Lowest-lying octet baryon masses in covariant baryon chiral perturbation theory

    OpenAIRE

    Ren, Xiu-Lei; Geng, Lisheng; Meng, Jie; Toki, Hiroshi

    2013-01-01

    We report on a systematic study of the ground-state octet baryon masses in the covariant baryon chiral perturbation theory with the extended-on-mass-shell renormalization scheme up to next-to-next-to-next-to-leading order, taking into account the contributions of the virtual decuplet baryons. A reasonable description of the lattice results is achieved by fitting simultaneously all the publicly available $n_f = 2+1$ lattice QCD data. It confirms that the various lattice simulations are consist...

  7. On the quark-mass dependence of baryon ground-state masses

    Energy Technology Data Exchange (ETDEWEB)

    Semke, Alexander

    2010-02-17

    Baryon masses of the flavour SU(3) octet and decuplet baryons are calculated in the framework of the Chiral Perturbations Theory - the effective field theory of the strong interaction. The chiral extrapolation to the higher meson (quark) masses is carried out. The comparison with the recent results on the baryon masses from lattice calculations are presented. (orig.)

  8. On the quark-mass dependence of baryon ground-state masses

    International Nuclear Information System (INIS)

    Baryon masses of the flavour SU(3) octet and decuplet baryons are calculated in the framework of the Chiral Perturbations Theory - the effective field theory of the strong interaction. The chiral extrapolation to the higher meson (quark) masses is carried out. The comparison with the recent results on the baryon masses from lattice calculations are presented. (orig.)

  9. Light baryon masses with dynamical twisted mass fermions

    CERN Document Server

    Alexandrou, C; Blossier, B; Brinet, M; Carbonell, J; Dimopoulos, P; Drach, V; Farchioni, F; Frezzotti, R; Guichon, P; Herdoiza, G; Jansen, K; Korzec, T; Koutsou, G; Liu, Z; Michael, C; Pène, O; Shindler, A; Urbach, C; Wenger, U

    2008-01-01

    We present results on the mass of the nucleon and the Delta using two dynamical degenerate twisted mass quarks. The evaluation is performed at four quark masses corresponding to a pion mass in the range of about 300-600 MeV on lattices of 2.1-2.7 fm. We check for cut-off effects by evaluating these baryon masses on lattices of spatial size 2.1 fm at beta=3.9 and beta=4.05 and on a lattice of 2.4 fm at beta=3.8. The values we find are compatible within our statistical errors. Lattice results are extrapolated to the physical limit using continuum chiral perturbation theory. Performing a combined fit to our lattice data at beta=3.9 and beta=4.05 we find a nucleon mass of 964\\pm 28 (stat.) \\pm 8 (syst.) MeV. The nucleon mass at the physical point provides an independent determination of the lattice spacing. Using heavy baryon chiral perturbation theory at O(p^3) we find a_{\\beta=3.9}=0.0890\\pm 0.0039(stat.) \\pm 0.0014(syst.) fm, and a_{\\beta=4.05}= 0.0691\\pm 0.0034(stat.) \\pm 0.0010(syst.) fm, in good agreement w...

  10. Light baryon masses with dynamical twisted mass fermions

    International Nuclear Information System (INIS)

    We present results on the mass of the nucleon and the Δ using two dynamical degenerate twisted mass quarks. The evaluation is performed at four quark masses corresponding to a pion mass in the range of about 300-600 MeV on lattices of 2.1-2.7 fm. We check for cut-off effects by evaluating these baryon masses on lattices of spatial size 2.1 fm at β=3.9 and β=4.05 and on a lattice of 2.4 fm at β=3.8. The values we find are compatible within our statistical errors. Lattice results are extrapolated to the physical limit using continuum chiral perturbation theory. Performing a combined fit to our lattice data at β=3.9 and β=4.05 we find a nucleon mass of 964±28(stat.)±8(syst.) MeV where we used the lattice spacings determined from the pion decay constant to convert to physical units. The systematic error due to the chiral extrapolation is estimated by comparing results obtained at O(p3) and O(p4) heavy baryon chiral perturbation theory. The nucleon mass at the physical point provides an independent determination of the lattice spacing. Using heavy baryon chiral perturbation theory at O(p3) we find aβ=3.9=0.0890±0.0039(stat.)±0.0014(syst.) fm, and aβ=4.05=0.0691±0.0034(stat.)±0.0010(syst.) fm, in good agreement with the values determined from the pion decay constant. Using results from our two smaller lattices spacings at constant r0m we estimate the continuum limit and check consistency with results from the coarser lattice. Results at the continuum limit are chirally extrapolated to the physical point. Isospin violating lattice artifacts in the Δ-system are found to be compatible with zero for the values of the lattice spacings used in this work. Performing a combined fit to our lattice data at β=3.9 and β=4.05 we find for the masses of the Δ++,- and Δ+,0 1316±60(stat.) MeV and 1330±74(stat.) MeV respectively. We confirm that in the continuum limit they are also degenerate. (orig.)

  11. Ground states and excitation spectra of baryons in a non-relativistic model with the anharmonic potential

    International Nuclear Information System (INIS)

    In this work the mass spectra for some of the baryon resonances of the particle data group with three and four star status are obtained, and a unified description of the ground states and excitation spectra of baryons are provided in the framework of a non-relativistic potential model. For this goal we have analytically solved the radial Schroedinger equation for three identical interacting particles with the anharmonic potential by using the Ansatz method and then we have calculated the baryon resonances spectrum by using the Goursey Radicati mass formula (GR) and with generalized Goursey Radicati mass formula (GGR). The results of our model show that the calculated masses of baryon resonances by using the generalized Goursey Radicati mass formula are found to be in good agreement with the tabulations of the Particle Data Group. The overall good description of the spectrum which we obtain shows that our model can also be used to give a fair description of the energies of the excited multiples up to 3 GeV mass and negative-parity resonance. Moreover, we have shown that our model reproduces the position of the Roper resonance of the nucleon. (authors)

  12. The quark-diquark rovibron and baryon spectra

    International Nuclear Information System (INIS)

    The observed phenomenon of clustering of resonances of different spins and parities to narrow mass bands in each of the nucleon and Δ spectra is explained within the framework of rotational-vibrational (rovibron) modes of a quark-diquark system. (author)

  13. Interrelations between baryon trajectories and new mass formulas for baryon octet

    International Nuclear Information System (INIS)

    In the framework of the dual analytic model the interrelations between Regge slopes and intercepts for baryon octet are obtained. The relations agree well with experiment and lead to new mass formulas for octets 1/2sup(+), 1/2sup(-) and their angular excitations

  14. Evaluation of the spectra of baryons containing two heavy quarks in a bag model

    International Nuclear Information System (INIS)

    In this work, we evaluate the mass spectra of baryons which consist of two heavy quarks and one light quark in the MIT bag model. The two heavy quarks constitute a heavy scalar or axial-vector diquark. Concretely, we calculate the spectra of vertical bar q(QQ')>1/2 and vertical bar q(QQ')>3/2 where Q and Q' stand for b and/or c quarks. Especially, for vertical bar q(bc)>1/2 there can be a mixing between vertical bar q(bc)0>1/2 and vertical bar q(bc)1>1/2 where the subscripts 0 and 1 refer to the spin state of the diquark (bc), the mixing is not calculable in the framework of quantum mechanics as the potential model is employed, but can be evaluated by the quantum field theory. Our numerical results indicate that the mixing is sizable

  15. Heavy baryons

    International Nuclear Information System (INIS)

    We review the experimental and theoretical status of baryons containing one heavy quark. The charm and bottom baryon states are classified and their mass spectra are listed. The appropriate theoretical framework for the description of heavy baryons is the Heavy Quark Effective Theory, whose general ideas and methods are introduced and illustrated in specific examples. We present simple covariant expressions for the spin wave functions of heavy baryons including p-wave baryons. The covariant spin wave functions are used to determine the Heavy Quark Symmetry structure of flavour-changing current-induced transitions between heavy baryons as well as one-pion and one-photon transitions between heavy baryons of the same flavour. We discuss 1/mQ corrections to the current-induced transitions as well as the structure of heavy to light baryon transitions. Whenever possible we attempt to present numbers to compare with experiment by making use of further model-dependent assumptions as e.g. the constituent picture for light quarks. We highlight recent advances in the theoretical understanding of the inclusive decays of hadrons containing one heavy quark including polarization. For exclusive semileptonic decays we discuss rates, angular decay distributions and polarization effects. We provide an update of the experimental and theoretical status of lifetimes of heavy baryons and of exclusive nonleptonic two body decays of charm baryons. (orig.)

  16. Octet baryon masses and sigma terms in covariant baryon chiral perturbation theory

    CERN Document Server

    Ren, Xiu-Lei; Meng, Jie

    2015-01-01

    We report on a recent study of the ground-state octet baryon masses and sigma terms in covariant baryon chiral perturbation theory with the extended-on-mass-shell scheme up to next-to-next-to-next-to-leading order. To take into account lattice QCD artifacts, the finite-volume corrections and finite lattice spacing discretization effects are carefully examined. We performed a simultaneous fit of all the $n_f = 2+1$ lattice octet baryon masses and found that the various lattice simulations are consistent with each other. Although the finite lattice spacing discretization effects up to $\\mathcal{O}(a^2)$ can be safely ignored, but the finite volume corrections cannot even for configurations with $M_\\phi L>4$. As an application, we predicted the octet baryon sigma terms using the Feynman-Hellmann theorem. In particular, the pion- and strangeness-nucleon sigma terms are found to be $\\sigma_{\\pi N} = 55(1)(4)$ MeV and $\\sigma_{sN} = 27(27)(4)$ MeV, respectively.

  17. Universal Neutrino Mass Hierarchy and Cosmological Baryon Number Asymmetry

    OpenAIRE

    Xing, Zhi-zhong

    2004-01-01

    We conjecture that three light Majorana neutrinos and their right-handed counterparts may have a universal geometric mass hierarchy. Incorporating this phenomenological conjecture with the Fritzsch texture of lepton mass matrices in a simple seesaw mechanism, we show that it is possible to simultaneously account for current neutrino oscillation data and the cosmological baryon number asymmetry via leptogenesis.

  18. Quantization State of Baryonic Mass in Clusters of Galaxies

    Directory of Open Access Journals (Sweden)

    Potter F.

    2007-01-01

    Full Text Available The rotational velocity curves for clusters of galaxies cannot be explained by Newtonian gravitation using the baryonic mass nor does MOND succeed in reducing this discrepancy to acceptable differences. The dark matter hypothesis appears to offer a solution; however, non-baryonic dark matter has never been detected. As an alternative approach, quantum celestial mechanics (QCM predicts that galactic clusters are in quantization states determined solely by the total baryonic mass of the cluster and its total angular momentum. We find excellent agreement with QCM for ten galactic clusters, demonstrating that dark matter is not needed to explain the rotation velocities and providing further support to the hypothesis that all gravitationally bound systems have QCM quantization states.

  19. Charge specific baryon mass formulas with deformed SU_q(3) flavor symmetry

    CERN Document Server

    Gresnigt, Niels G

    2016-01-01

    The quantum group $SU_q(3)=U_q(su(3))$ is taken as a baryon flavor symmetry to derive mass sum rules for octet and decuplet baryons. Accounting for electromagnetic contributions to baryons masses to zeroth order, the new charge specific $q$-deformed octet and decuplet baryon mass formulas are accurate to 0.02% and 0.08% respectively. A new relation between the octet and decuplet baryon masses that is accurate to 1.0% is derived. An explicit formula for the Cabibbo angle, taken to be $\\frac{\\pi}{14}$, in terms of the deformation parameter $q$ and $J^P$ of the baryons is obtained.

  20. Baryon masses with improved staggered quarks

    CERN Document Server

    Bernard, C; DeTar, C; Gottlieb, S; Heller, U M; Hetrick, J E; Levkova, L; Osborn, J; Renner, D B; Sugar, R; Toussaint, D

    2007-01-01

    The MILC collaboration's simulations with improved staggered quarks are being extended with runs at a lattice spacing of 0.06 fm with quark masses down to one tenth the strange quark mass. We give a brief introduction to these new simulations and the determination of the lattice spacing. Then we combine these new runs with older results to study the masses of the nucleon and the Omega minus in the continuum and chiral limits.

  1. Search for Low Mass Exotic Baryons in One Pion Electroproduction Data Measured at JLAB

    Energy Technology Data Exchange (ETDEWEB)

    B. Tatischeff; E. Tomasi-Gustafsson

    2007-02-05

    This paper aims to give further evidence for the existence of low mass exotic baryons. Narrow structures in baryonic missing mass or baryonic invariant mass were previously observed during the last ten years. Since their existence is sometimes questionable, the structure functions of one pion electroproduction cross sections, measured at JLAB, are studied to add informations on the possible existence of these narrow exotic baryonic resonances.

  2. Chiral perturbation theory analysis of baryon temperature mass shifts

    CERN Document Server

    Bedaque, P F

    1995-01-01

    We compute the finite temperature pole mass shifts of the octet and decuplet baryons using heavy baryon chiral perturbation theory and the 1/N_c expansion, where N_c is the number of QCD colors. We consider the temperatures of the order of the pion mass m_\\pi, and expand truncate the chiral and 1/N_c expansions assuming that m_\\pi \\sim 1/N_c. There are three scales in the problem: the temperature T, the pion mass m_\\pi, and the octet--decuplet mass difference. Therefore, the result is not simply a power series in T. We find that the nucleon and \\Delta temperature mass shifts are opposite in sign, and that their mass difference changes by 20% in the temperature range 90 MeV < T < 130 MeV, that is the range where the freeze out in relativistic heavy ion collisions is expected to occur. We argue that our results are insensitive to the neglect of 1/N_c- supressed effects; the main purpose of the 1/N_c expansion in this work is to justify our treatment of the decuplet states.

  3. Observation and Mass Measurement of the Baryon $\\Xi^-_b$

    CERN Document Server

    Aaltonen, T; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P H; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bölla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, Yu; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carrillo, S; Carlsmith, D; Carosi, R; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Cilijak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca-Almenar, C; Cuevas-Maestro, J; Culbertson, R; Cully, J C; Da Ronco, S; Datta, M; D'Auria, S; Davies, T; Dagenhart, D; De Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; De Lorenzo, G; Dell'Orso, Mauro; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Dorr, C; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernández, J P; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; García, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Golossanov, A; Gómez, G; Gómez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimarães da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Höcker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraan, A C; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lu, R S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Mäki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis, A; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Martinez-Ballarin, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtälä, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moon, C S; Moore, R; Morello, M; Movilla-Fernández, P A; Mülmenstädt, J; Mukherjee, A; Müller, T; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Österberg, K; Pagliarone, C; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, Aldo L; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Reisert, B; Rekovic, V; Renton, P B; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Safonov, A; Sakumoto, W K; Salamanna, G; Salto, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyrla, A; Shalhout, S Z; Shapiro, M D; Shears, T G; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakian, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Söderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; Saint-Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuno, S; Tu, Y; Turini, N; Ukegawa, F; Uozumi, S; Vallecorsa, S; Van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Veramendi, G; Veszpremi, V; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Vollrath, I; Volobuev, I P; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, J; Wagner, W; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhou, J; Zucchelli, S

    2007-01-01

    We report the observation and measurement of the mass of the bottom, strange baryon $\\Xi^-_b$ through the decay chain $\\Xi^-_b \\to J/\\psi \\Xi^-$, where $J/\\psi \\to \\mu^+ \\mu^-$, $\\Xi^- \\to \\Lambda \\pi^-$, and $\\Lambda \\to p \\pi^-$. Evidence for observation is based on a signal whose probability of arising from the estimated background is $6.6 \\times 10^{-15}$, or 7.7 Gaussian standard deviations. The $\\Xi^-_b$ mass is measured to be $5792.9\\pm 2.5$ (stat.) $\\pm 1.7$ (syst.) MeV/$c^2$.

  4. Simple-minded estimate of the masses of baryons containing single heavy quarks

    OpenAIRE

    Zalewska, Agnieszka; Zalewski, Kacper

    1996-01-01

    The masses of the yet undiscovered baryons containing single $c$ or $b$ quarks are estimated from the known masses using the following rules: equal distances in mass between the isomultiplets forming sextets, equal mass differences between the corresponding spin one-half baryons containing $c$ and $b$ quarks, hyperfine splittings inversely proportional to the masses of the heavy quarks.

  5. Strange and charm baryon masses with two flavors of dynamical twisted mass fermions

    International Nuclear Information System (INIS)

    The masses of the low-lying strange and charm baryons are evaluated using two degenerate flavors of twisted mass sea quarks for pion masses in the range of about 260 MeV to 450 MeV. The strange and charm valence quark masses are tuned to reproduce the mass of the kaon and D-meson at the physical point. The tree-level Symanzik improved gauge action is employed. We use three values of the lattice spacing, corresponding to β=3.9, β=4.05 and β=4.2 with r0/a=5.22(2), r0/a=6.61(3) and r0/a=8.31(5) respectively. We examine the dependence of the strange and charm baryons on the lattice spacing and strange and charm quark masses. The pion mass dependence is studied and physical results are obtained using heavy baryon chiral perturbation theory to extrapolate to the physical point.

  6. On the quark-mass dependence of the baryon ground-state masses

    CERN Document Server

    Semke, A

    2011-01-01

    We perform a chiral extrapolation of the baryon octet and decuplet masses in a relativistic formulation of chiral perturbation theory. A partial summation is assumed as implied by the use of physical baryon and meson masses in the one-loop diagrams. Upon a chiral expansion our results are consistent with strict chiral perturbation theory at the next-to-next-to-next-to-leading order. All counter terms are correlated by a large-$N_c$ operator analysis. Our results are confronted with recent results of unquenched three flavor lattice simulations. We adjust the parameter set to the pion-mass dependence of the nucleon and omega masses as computed by the BMW group and predict the pion-mass dependence of the remaining baryon octet and decuplet states. The current lattice simulations can be described accurately and smoothly up to pion masses of about 600 MeV. In particular we recover the recent results of HSC without any further adjustments.

  7. The different baryonic Tully-Fisher relations at low masses

    CERN Document Server

    Brook, C B; Stinson, G

    2016-01-01

    We compare the Baryonic Tully-Fisher relation (BTFR) of simulations and observations of galaxies ranging from dwarfs to spirals, using various measures of rotational velocity Vrot. We explore the BTFR when measuring Vrot at the flat part of the rotation curve, Vflat, at the extent of HI gas, Vlast, and using 20% (W20) and 50% (W50) of the width of HI line profiles. We also compare with the maximum circular velocity of the parent halo, Vmax, within dark matter only simulations. The different BTFRs increasingly diverge as galaxy mass decreases. Using Vlast one obtains a power law over four orders of magnitude in baryonic mass, with slope similar to the observed BTFR. Measuring Vflat gives similar results as Vlast when galaxies with rising rotation curves are excluded. However, higher rotation velocities would be found for low mass galaxies if the cold gas extended far enough for Vrot to reach a maximum. W20 gives a similar slope as Vlast but with slightly lower values of Vrot for low mass galaxies, although thi...

  8. Automatic identification of mass spectra

    International Nuclear Information System (INIS)

    Several approaches to preprocessing and comparison of low resolution mass spectra have been evaluated by various test methods related to library search. It is shown that there is a clear correlation between the nature of any contamination of a spectrum, the basic principle of the transformation or distance measure, and the performance of the identification system. The identification of functionality from low resolution spectra has also been evaluated using several classification methods. It is shown that there is an upper limit to the success of this approach, but also that this can be improved significantly by using a very limited amount of additional information. 10 refs

  9. Measurement of the mass of the $\\Lambda_{b}$ baryon

    CERN Document Server

    Buskulic, Damir; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Casado, M P; Chmeissani, M; Crespo, J M; Delfino, M C; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Alemany, R; Bazarko, A O; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Moneta, L; Oest, T; Palla, Fabrizio; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wagner, A; Wildish, T; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Gay, P; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Wäänänen, A; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Abbaneo, D; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Konstantinidis, N P; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Verdini, P G; Walsh, J; Blair, G A; Bryant, L M; Cerutti, F; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Köksal, A; Letho, M; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Büscher, V; Cowan, G D; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Greening, T C; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1996-01-01

    In a data sample of four million hadronic \\Z\\ decays collected with the ALEPH detector at LEP, four $\\Lambda_b$ baryon candidates are exclusively reconstructed in the $\\Lambda_b \\rightarrow \\Lambda_c^+ \\pi^-$ channel, with the $\\Lambda_c^+$ decaying into $pK^-\\pi^+$, $p\\bar{K^0}$, or $\\Lambda\\pi^+\\pi^+\\pi^-$. The probability of the observed signal to be due to a background fluctuation is estimated to be $4.2 \\times 10^{-4}$. The mass of the $\\Lambda_b$ is measured to be $5614 \\pm 21 \\, (stat.) \\pm 4 \\, (syst.)~\\mevcc$. %$5614\\pm 21\\,(stat.) \\pm 4\\,(syst.) \\mevcc$.

  10. Calculation of baryon sum rules and SU(4) mass formulae for mesons and baryons

    International Nuclear Information System (INIS)

    Light cone coordinates and field-field anticommutators for the free quark model on the light cone are introduced and light cone charges and light cone currents for the free quark model as well as sum rules for the meson and quark states are derived. The derivation of sum rules for the baryons is attempted. It is seen that it is possible formally to derive the same sum rules for the baryons and for the quarks. The baryon sums were derived through the symmetry properties of the baryon fields. Explicit assumptions about the spatial distribution of the three quarks in the baryons were not utilized. The meson-baryon Σ-terms, Zweig's rules in the SU (4) and a number of properties of the M-matrix are discussed. (BJ)

  11. Octet baryon mass splittings from up-down quark mass differences

    CERN Document Server

    Horsley, R; Nakamura, Y; Pleiter, D; Rakow, P E L; Schierholz, G; Zanotti, J M

    2012-01-01

    Using an SU(3) flavour symmetry breaking expansion in the quark mass, we determine the QCD component of the neutron-proton, Sigma and Xi mass splittings of the baryon octet due to up-down (and strange) quark mass differences. Provided the average quark mass is kept constant, the expansion coefficients in our procedure can be determined from computationally cheaper simulations with mass degenerate sea quarks and partially quenched valence quarks. Full details and numerical results are given in ref 1.

  12. Observed supersymmetry in baryon and meson spectra with IBFM, the interacting boson fermion model

    International Nuclear Information System (INIS)

    Supersymetry is already observed in (i) nuclear physics where the same empirical formula based on a graded Lie group describles even-even and odd-even nuclear spectra and (ii) in Nambu-BCS theory where there is a simple relationship between the energy gap of the basic fermion and the bosonic collective modes. Similar relationships between large number of mesonic and baryonic excitations based on the SU(3) substructure in the U(15/30) graded Lie group, are proposed. (author)

  13. Effective Kaon Mass in Baryonic Matter and Kaon Condensation

    CERN Document Server

    Yabu, H; Myhrer, F; Kubodera, K; Yabu, Hiroyuki; Nakamura, Shinji

    1993-01-01

    The effective kaon mass in dense baryonic matter is calculated based on PCAC, current algebra and the Weinberg smoothness hypothesis. The off-shell behavior of the K-N scattering amplitudes is treated consistently with PCAC, and the effects of the subthreshold K-N resonances are also included. The effective kaon mass is found to depend crucially on the K-N sigma term. Since the current estimates of K-N Sigma term are very uncertain, we discuss various scenarios treating K-N Sigma term as an input parameter; for certain values of K-N Sigma a collective mode of a hyperon-particle-nucleon-hole state appears at high densities, possibly leading to kaon condensation.

  14. Relativistic calculation of ground-state baryon masses

    International Nuclear Information System (INIS)

    The masses of the ground-state baryons are calculated in a relativistic quark model by using the saddle-point variational method to solve the three-body Breit equation. The saddle-point variational method maximizes the energy with respect to small component parameters, while minimizing with respect to size parameters. This removes the problems usually caused by negative-energy states, without the need for positive-energy projection operators. The variational method, applied to an asymmetric trial wave function with naturally broken SU(3) and SU(6) symmetry, permits solution of the Breit equation for realistic QCD-inspired potentials without using perturbation theory. The calculated masses are in good agreement with experiment, and the asymmetric wave function gives reasonable values for the proton and neutron charge radii. ((orig.))

  15. Light Baryons Mass in a Non-Relativistic Quark Model within an Hypercentral Power Low Potential

    CERN Document Server

    Salehi, Nasrin

    2016-01-01

    In this work, we calculated the baryon mass within a non-relativistically quark model using an approach based on the G\\"ursey Radicati mass formula (GR). The average energy value of each SU(6) multiplet is described using the SU(6) invariant interaction given by a hypercentral potential. In our series studies we investigate different interactions and situations to gain the best possible model. This goal can be obtained by checking and studying various potentials in different situations. In this paper we present the solution of the Schr\\"odinger equation with an hypercentral power low potential. The results of our model (the combination of our proposed hypercentral Potential and generalized GR mass formula to description of the spectrum) show that the strange and non-strange baryons spectra are in general fairly well reproduced. The overall good description of the mass which we obtain shows that our model can also be used to give a fair description of the energies of the excited multiplets up to three GeV and ...

  16. Partially quenched study of strange baryon with N{sub f}=2 twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Drach, Vincent; Brinet, Mariane; Carbonell, Jaume [UJF, CNRS/IN2P3, INPG, Grenoble (FR). Lab. de Physique Subatomique et de Cosmologie] (and others)

    2009-06-15

    We present results on the mass of the baryon octet and decuplet using two flavors of light dynamical twisted mass fermions. The strange quark mass is fixed to its physical value from the kaon sector in a partially quenched set up. Calculations are performed for light quark masses corresponding to a pion mass in the range 270-500 MeV and lattice sizes of 2.1 fm and 2.7 fm. We check for cut-off effects and isospin breaking by evaluating the baryon masses at two different lattice spacings. We carry out a chiral extrapolation for the octet baryons and discuss results for the {omega}. (orig.)

  17. Partially quenched study of strange baryon with Nf = 2 twisted mass fermions

    CERN Document Server

    Drach, V; Carbonell, J; Alexandrou, Z L C; Korzec, T; Koutsou, G; Baron, R; Guichon, P; Pène, O; Pallante, E; Reker, S; Urbach, C; Jansen, K

    2008-01-01

    We present results on the mass of the baryon octet and decuplet using two flavors of light dynamical twisted mass fermions. The strange quark mass is fixed to its physical value from the kaon sector in a partially quenched set up. Calculations are performed for light quark masses corresponding to a pion mass in the range 270-500 MeV and lattice sizes of 2.1 fm and 2.7 fm. We check for cut-off effects and isospin breaking by evaluating the baryon masses at two different lattice spacings. We carry out a chiral extrapolation for the octet baryons and discuss results for the Omega.

  18. Evidence for non-analytic light quark mass dependence in the baryon spectrum

    CERN Document Server

    Walker-Loud, Andre

    2011-01-01

    Using precise lattice QCD computations of the baryon spectrum, we present the first direct evidence for the presence of contributions to the baryon masses which are non-analytic in the light quark masses; contributions which are often denoted "chiral logarithms". We isolate the poor convergence of SU(3) baryon chiral perturbation theory to the flavor-singlet mass combination. The flavor-octet baryon mass splittings, which are corrected by chiral logarithms at next to leading order in SU(3) chiral perturbation theory, yield baryon-pion axial coupling constants D, F, C and H consistent with QCD values; the first evidence of chiral logarithms in the baryon spectrum. The Gell-Mann--Okubo relation, a flavor-27 baryon mass splitting, which is dominated by chiral corrections from light quark masses, provides further evidence for the presence of non-analytic light quark mass dependence in the baryon spectrum; we simultaneously find the GMO relation to be inconsistent with the first few terms in a taylor expansion in ...

  19. The baryonic mass-velocity relation; clues to feedback processes during structure formation and the cosmic baryon inventory

    CERN Document Server

    Mayer, L; Mayer, Lucio; Moore, Ben

    2003-01-01

    We show that a global relation between baryonic mass and virial velocity can be constructed from the scale of dwarf galaxies up to that of rich galaxy clusters. The slope of this relation is close to that expected if dark matter halos form in the standard hierarchical cosmogony and capture a universal baryon fraction, once the details of halo structure and the adiabatic contraction of halos due to cooling gas are taken into account. The scatter and deficiency of baryons within low mass halos ($V_{vir} < 50$ km/s) is consistent with the expected suppression of gas accretion by photo-evaporation due to the cosmic UV background at high redshift. The data are not consistent with significant gas removal from strong supernovae winds unless the velocities of galaxies measured from their gas kinematics are significantly lower than the true halo velocities for objects with $V_{vir} < 100$ km/s. Thus models such as $\\Lambda$CDM with a steep mass function of halos may find it difficult to reproduce both the baryon...

  20. Strange and charm baryon masses with two flavors of dynamical twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrou, C. [Univ. of Cyprus, Nicosia (Cyprus). Dept. of Physics; Cyprus Institute, Nicosia (Cyprus). Computation-Based Science and Technology Research Center; Carbonell, J. [CEA-Saclay, Gif-sur-Yvette (France). IRFU/Service de Physique Nucleaire; Christaras, D.; Gravina, M. [Univ. of Cyprus, Nicosia (Cyprus). Dept. of Physics; Drach, V. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Papinutto, M. [UFJ/CNRS/IN2P3, Grenoble (France). Laboratoire de Physique Subatomique et Cosmologie; Universidad Autonoma de Madrid (Spain). Dept. de Fisica Teorica; Universidad Autonoma de Madrid UAM/CSIC (Spain). Inst. de Fisica Teorica

    2012-10-15

    The masses of the low-lying strange and charm baryons are evaluated using two degenerate flavors of twisted mass sea quarks for pion masses in the range of about 260 MeV to 450 MeV. The strange and charm valence quark masses are tuned to reproduce the mass of the kaon and D-meson at the physical point. The tree-level Symanzik improved gauge action is employed. We use three values of the lattice spacing, corresponding to {beta}=3.9, {beta}=4.05 and {beta}=4.2 with r{sub 0}/a=5.22(2), r{sub 0}/a=6.61(3) and r{sub 0}/a=8.31(5) respectively. We examine the dependence of the strange and charm baryons on the lattice spacing and strange and charm quark masses. The pion mass dependence is studied and physical results are obtained using heavy baryon chiral perturbation theory to extrapolate to the physical point.

  1. Baryon spectroscopy in lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Derek B. Leinweber; Wolodymyr Melnitchouk; David Richards; Anthony G. Williams; James Zanotti

    2004-04-01

    We review recent developments in the study of excited baryon spectroscopy in lattice QCD. After introducing the basic methods used to extract masses from correlation functions, we discuss various interpolating fields and lattice actions commonly used in the literature. We present a survey of results of recent calculations of excited baryons in quenched QCD, and outline possible future directions in the study of baryon spectra.

  2. RESOLVE and ECO: The Halo Mass-Dependent Shape of Galaxy Stellar and Baryonic Mass Functions

    CERN Document Server

    Eckert, Kathleen D; Stark, David V; Moffett, Amanda J; Berlind, Andreas A; Norris, Mark A

    2016-01-01

    In this work, we present galaxy stellar and baryonic (stars plus cold gas) mass functions (SMF and BMF) and their halo mass dependence for two volume-limited data sets. The first, RESOLVE-B, coincides with the Stripe 82 footprint and is extremely complete down to baryonic mass Mbary ~ 10^9.1 Msun, probing the gas-rich dwarf regime below Mbary ~ 10^10 Msun. The second, ECO, covers a ~40 times larger volume (containing RESOLVE-A) and is complete to Mbary ~ 10^9.4 Msun. To construct the SMF and BMF we implement a new "cross-bin sampling" technique with Monte Carlo sampling from the full likelihood distributions of stellar or baryonic mass. Our SMFs exhibit the "plateau" feature starting below Mstar ~ 10^10 Msun that has been described in prior work. However, the BMF fills in this feature and rises as a straight power law below ~10^10 Msun, as gas-dominated galaxies become the majority of the population. Nonetheless, the low-mass slope of the BMF is not as steep as that of the theoretical dark matter halo MF. Mor...

  3. Constraining amplitude and slope of the mass fluctuation spectrum using cluster baryon mass function

    CERN Document Server

    Voevodkin, A

    2004-01-01

    We derive the baryon mass function for a complete sample of low-redshift clusters and argue that it is an excellent proxy for the total mass function if the ratio f_b=M_b/M_tot in all clusters is close to its universal value, Omega_b/Omega_M. Under this assumption, the baryon mass function can be used to constrain the amplitude and slope of the density fluctuations power spectrum on cluster scales. This method does not use observational determinations of the total mass and thus bypasses major uncertainties in the traditional analyses based on the X-ray temperature function. However, it is sensitive to possible systematic variations of the baryon fraction as a function of cluster mass. Adapting a weak dependence f_b(M) suggested by observations and numerical simulations by Bialek et al., we derive sigma_8=0.72+-0.04 and the shape parameter Omega_M*h=0.13+-0.07, in good agreement with a number of independent methods. We discuss the sensitivity of these values to other cosmological parameters and to different as...

  4. Constraining Amplitude and Slope of the Mass Fluctuation Spectrum Using a Cluster Baryon Mass Function

    Science.gov (United States)

    Voevodkin, A.; Vikhlinin, A.

    2004-02-01

    We derive the baryon mass function for a complete sample of low-redshift clusters and argue that it is an excellent proxy for the total mass function if the ratio fb=Mb/Mtot in all clusters is close to its universal value, Ωb/ΩM. Under this assumption, the baryon mass function can be used to constrain the amplitude and slope of the density fluctuation power spectrum on cluster scales. This method does not use observational determinations of the total mass and thus bypasses major uncertainties in the traditional analyses based on the X-ray temperature function. However, it is sensitive to possible systematic variations of the baryon fraction as a function of cluster mass. Adapting a weak dependence fb(M), suggested by observations and numerical simulations by Bialek et al., we derive σ8=0.72+/-0.04 and the shape parameter ΩMh=0.13+/-0.07, in good agreement with a number of independent methods. We discuss the sensitivity of these values to other cosmological parameters and to different assumptions about variations in fb.

  5. The baryon mass calculation in the chiral soliton model at finite temperature and density

    International Nuclear Information System (INIS)

    In the mean-field approximation, we have studied the soliton which is embedded in a thermal medium within the chiral soliton model. The energy of the soliton or the baryon mass in the thermal medium has been carefully evaluated, in which we emphasize that the thermal effective potential in the soliton energy should be properly treated in order to derive a finite and well-defined baryon mass out of the thermal background. The result of the baryon mass at finite temperatures and densities in chiral soliton model are clearly presented. (author)

  6. RESOLVE and ECO: The Halo Mass-dependent Shape of Galaxy Stellar and Baryonic Mass Functions

    Science.gov (United States)

    Eckert, Kathleen D.; Kannappan, Sheila J.; Stark, David V.; Moffett, Amanda J.; Berlind, Andreas A.; Norris, Mark A.

    2016-06-01

    In this work, we present galaxy stellar and baryonic (stars plus cold gas) mass functions (SMF and BMF) and their halo mass dependence for two volume-limited data sets. The first, RESOLVE-B, coincides with the Stripe 82 footprint and is extremely complete down to baryonic mass M bary ∼ 109.1 M ⊙, probing the gas-rich dwarf regime below M bary ∼ 1010 M ⊙. The second, ECO, covers a ∼40× larger volume (containing RESOLVE-A) and is complete to M bary ∼ 109.4 M ⊙. To construct the SMF and BMF we implement a new “cross-bin sampling” technique with Monte Carlo sampling from the full likelihood distributions of stellar or baryonic mass. Our SMFs exhibit the “plateau” feature starting below M star ∼ 1010 M ⊙ that has been described in prior work. However, the BMF fills in this feature and rises as a straight power law below ∼1010 M ⊙, as gas-dominated galaxies become the majority of the population. Nonetheless, the low-mass slope of the BMF is not as steep as that of the theoretical dark matter halo MF. Moreover, we assign group halo masses by abundance matching, finding that the SMF and BMF, separated into four physically motivated halo mass regimes, reveal complex structure underlying the simple shape of the overall MFs. In particular, the satellite MFs are depressed below the central galaxy MF “humps” in groups with mass <1013.5 M ⊙ yet rise steeply in clusters. Our results suggest that satellite destruction and stripping are active from the point of nascent group formation. We show that the key role of groups in shaping MFs enables reconstruction of a given survey’s SMF or BMF based on its group halo mass distribution.

  7. Baryon number asymmetry and dark matter in the neutrino mass model with an inert doublet

    OpenAIRE

    Kashiwase, Shoichi; Suematsu, Daijiro

    2012-01-01

    The radiative neutrino mass model with an inert doublet scalar has been considered as a promising candidate which can explain neutrino masses, dark matter abundance and baryon number asymmetry if dark matter is identified with the lightest neutral component of the inert doublet. We reexamine these properties by imposing all the data of the neutrino oscillation, which are recently suggested by the reactor experiments. We find that the sufficient baryon number asymmetry seems not to be easily g...

  8. The Stripe 82 Massive Galaxy Project - II. Stellar mass completeness of spectroscopic galaxy samples from the Baryon Oscillation Spectroscopic Survey

    Science.gov (United States)

    Leauthaud, Alexie; Bundy, Kevin; Saito, Shun; Tinker, Jeremy; Maraston, Claudia; Tojeiro, Rita; Huang, Song; Brownstein, Joel R.; Schneider, Donald P.; Thomas, Daniel

    2016-04-01

    The Baryon Oscillation Spectroscopic Survey (BOSS) has collected spectra for over one million galaxies at 0.15 11.6 only in the narrow redshift range z = [0.51, 0.61]. The low-redshift LOWZ sample is 80 per cent complete at log 10(M*/M⊙) > 11.6 for z = [0.15, 0.43]. To construct mass complete samples at lower masses, spectroscopic samples need to be significantly supplemented by photometric redshifts. This work will enable future studies to better utilize the BOSS samples for galaxy-formation science.

  9. The baryonic mass assembly of low-mass halos in a Lambda-CDM Universe

    CERN Document Server

    De Rossi, Maria E; Tissera, Patricia B; Gonzalez-Samaniego, Alejandro; Pedrosa, Susana

    2014-01-01

    We analyse the dark, gas, and stellar mass assembly histories of low-mass halos (Mvir ~ 10^10.3 - 10^12.3 M_sun) identified at redshift z = 0 in cosmological numerical simulations. Our results indicate that for halos in a given present-day mass bin, the gas-to-baryon fraction inside the virial radius does not evolve significantly with time, ranging from ~0.8 for smaller halos to ~0.5 for the largest ones. Most of the baryons are located actually not in the galaxies but in the intrahalo gas; for the more massive halos, the intrahalo gas-to-galaxy mass ratio is approximately the same at all redshifts, z, but for the least massive halos, it strongly increases with z. The intrahalo gas in the former halos gets hotter with time, being dominant at z = 0, while in the latter halos, it is mostly cold at all epochs. The multiphase ISM and thermal feedback models in our simulations work in the direction of delaying the stellar mass growth of low-mass galaxies.

  10. Strange and charmed baryons using N{sub f}=2 twisted mass QCD

    Energy Technology Data Exchange (ETDEWEB)

    Papinutto, Mauro; Carbonell, Jaume [UJF, CNRS/IN2P, INPG (France). Lab. de Physique Subatomique et de Cosmologie; Drach, Vincent [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Alexandrou, Constantia [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics

    2010-12-15

    We compute the mass spectrum for strange/charmed baryons in the partially quenched approach using N{sub f}=2 twisted mass QCD configurations. We investigate two main issues: the size of lattice artefacts using three values of the lattice spacing (the smallest of which is approximately 0.05 fm) and the dependence of baryon masses on meson (or quark) masses. We thus perform a global fit in order to extrapolate simultaneously to the continuum limit and to the physical point. We estimate the masses of {omega}{sub sss}, {xi}{sub dss}, {lambda}{sub uds}, {omega}{sub ccc}, {xi}{sub dcc}, {lambda}{sub udc}. (orig.)

  11. Hadron Spectra and Quark Mass Dependence in Holographic QCD

    Science.gov (United States)

    Hashimoto, K.

    Hadron masses and their quark-mass dependence are imporatant observablesin strongly coupled QCD. We apply holography, a string theory technique, to this problem, and find a qualitative coincidence with observed data of baryon spectra. This talk, presented on 9th Feruary 2010 in ``NFQCD'' workshop at YITP, is based on three papers written with my collaborators [K.~Hashimoto, T.~Hirayama, F.~L.~Lin and H.~U.~Yee, J. High Energy Phys. 07 (2008), 089, arXiv:0803.4192. K.~Hashimoto, T.~Hirayama and D.~K.~Hong, Phys. Rev. D 81 (2010), 045016, arXiv:0906.0402. K.~Hashimoto, N.~Iizuka, T.~Ishii and D.~Kadoh, Phys. Lett. B 691 (2010), 65, arXiv:0910.1179.

  12. An interacting quark-diquark model. Strange and nonstrange baryon spectroscopy and other observables

    CERN Document Server

    De Sanctis, M; Vsevolodovna, R Magaña; Saracco, P; Santopinto, E

    2016-01-01

    We describe the relativistic interacting quark-diquark model formalism and its application to the calculation of strange and nonstrange baryon spectra. The results are compared to the existing experimental data. We also discuss the application of the model to the calculation of other baryon observables, like baryon magnetic moments, open-flavor strong decays and baryon masses with self-energy corrections.

  13. Center-of-mass motion effects in static properties of baryons

    International Nuclear Information System (INIS)

    The center-of-mass motion effects in the statc properties of baryons (the Gsub(A)/Gsub(V) value, the proton magnetic moment and rms radius, and Asup((1)) and Ssup((2)) constants of the nonleptonic decays of baryons) are considered for some kinds of the potentials in the mean-field approximation. It is pointed out the potential form is rather essential for the values of the rms radius and Asup((1)) and Asup((2)) constants

  14. An accurate halo model for fitting non-linear cosmological power spectra and baryonic feedback models

    CERN Document Server

    Mead, Alexander; Heymans, Catherine; Joudaki, Shahab; Heavens, Alan

    2015-01-01

    We present an optimised variant of the halo model, designed to produce accurate matter power spectra well into the non-linear regime for a wide range of cosmological models. To do this, we introduce physically-motivated free parameters into the halo-model formalism and fit these to data from high-resolution N-body simulations. For a variety of $\\Lambda$CDM and $w$CDM models the halo-model power is accurate to $\\simeq 5$ per cent for $k\\leq 10h\\,\\mathrm{Mpc}^{-1}$ and $z\\leq 2$. We compare our results with recent revisions of the popular HALOFIT model and show that our predictions are more accurate. An advantage of our new halo model is that it can be adapted to account for the effects of baryonic feedback on the power spectrum. We demonstrate this by fitting the halo model to power spectra from the OWLS hydrodynamical simulation suite via parameters that govern halo internal structure. We are able to fit all feedback models investigated at the 5 per cent level using only two free parameters, and we place limi...

  15. Mass and magnetic dipole moment of negative parity heavy baryons with spin--3/2

    CERN Document Server

    Azizi, K

    2015-01-01

    We calculate the mass and residue of the heavy spin--3/2 negative parity baryons with single heavy bottom or charm quark by the help of a two-point correlation function. We use the obtained results to investigate the diagonal radiative transitions among the baryons under consideration. In particular, we compute corresponding transition form factors via light cone QCD sum rules which are then used to obtain the magnetic dipole moments of the heavy spin--3/2 negative parity baryons. We remove the pollutions coming from the positive parity spin--3/2 and positive/negative parity spin--1/2 baryons by constructing sum rules for different Lorentz structures. We compare the results obtained with the existing theoretical predictions.

  16. Low-lying baryon spectrum with two dynamical twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrou, C. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Computation-based Science and Technology Research Center, Cyprus Institute, Nicosia (Cyprus); Baron, R.; Guichon, P. [CEA-Saclay, IRFU/Service de Physique Nucleaire, Gif-sur-Yvette (France); Carbonell, J.; Drach, V. [UJF/CNRS/IN2P3, Grenoble (France). Lab. de Physique Subatomique et Cosmologie; Jansen, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Korzec, T. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Pene, O. [Paris-11 Univ., 91 - Orsay (France). Lab. de Physique Theorique

    2009-10-15

    The masses of the low lying baryons are evaluated using two degenerate flavors of twisted mass sea quarks corresponding to pseudo scalar masses in the range of about 270 MeV to 500 MeV. The strange valence quark mass is tuned to reproduce the mass of the kaon in the physical limit. The tree-level Symanzik improved gauge action is employed. We use lattices of spatial size 2.1 fm and 2.7 fm at two values of the lattice spacing with r{sub 0}/a=5.22(2) and r{sub 0}/a=6.61(3). We check for both finite volume and cut-off effects on the baryon masses. We performed a detailed study of the chiral extrapolation of the octet and decuplet masses using SU(2) {chi}PT. The lattice spacings determined using the nucleon mass at the physical point are consistent with the values extracted using the pion decay constant. We examine the issue of isospin symmetry breaking for the octet and decuplet baryons and its dependence on the lattice spacing. We show that in the continuum limit isospin breaking is consistent with zero, as expected. The baryon masses that we find after taking the continuum limit and extrapolating to the physical limit are in good agreement with experiment. (orig.)

  17. Low-lying baryon spectrum with two dynamical twisted mass fermions

    International Nuclear Information System (INIS)

    The masses of the low lying baryons are evaluated using two degenerate flavors of twisted mass sea quarks corresponding to pseudo scalar masses in the range of about 270 MeV to 500 MeV. The strange valence quark mass is tuned to reproduce the mass of the kaon in the physical limit. The tree-level Symanzik improved gauge action is employed. We use lattices of spatial size 2.1 fm and 2.7 fm at two values of the lattice spacing with r0/a=5.22(2) and r0/a=6.61(3). We check for both finite volume and cut-off effects on the baryon masses. We performed a detailed study of the chiral extrapolation of the octet and decuplet masses using SU(2) χPT. The lattice spacings determined using the nucleon mass at the physical point are consistent with the values extracted using the pion decay constant. We examine the issue of isospin symmetry breaking for the octet and decuplet baryons and its dependence on the lattice spacing. We show that in the continuum limit isospin breaking is consistent with zero, as expected. The baryon masses that we find after taking the continuum limit and extrapolating to the physical limit are in good agreement with experiment. (orig.)

  18. An accurate halo model for fitting non-linear cosmological power spectra and baryonic feedback models

    Science.gov (United States)

    Mead, A. J.; Peacock, J. A.; Heymans, C.; Joudaki, S.; Heavens, A. F.

    2015-12-01

    We present an optimized variant of the halo model, designed to produce accurate matter power spectra well into the non-linear regime for a wide range of cosmological models. To do this, we introduce physically motivated free parameters into the halo-model formalism and fit these to data from high-resolution N-body simulations. For a variety of Λ cold dark matter (ΛCDM) and wCDM models, the halo-model power is accurate to ≃ 5 per cent for k ≤ 10h Mpc-1 and z ≤ 2. An advantage of our new halo model is that it can be adapted to account for the effects of baryonic feedback on the power spectrum. We demonstrate this by fitting the halo model to power spectra from the OWLS (OverWhelmingly Large Simulations) hydrodynamical simulation suite via parameters that govern halo internal structure. We are able to fit all feedback models investigated at the 5 per cent level using only two free parameters, and we place limits on the range of these halo parameters for feedback models investigated by the OWLS simulations. Accurate predictions to high k are vital for weak-lensing surveys, and these halo parameters could be considered nuisance parameters to marginalize over in future analyses to mitigate uncertainty regarding the details of feedback. Finally, we investigate how lensing observables predicted by our model compare to those from simulations and from HALOFIT for a range of k-cuts and feedback models and quantify the angular scales at which these effects become important. Code to calculate power spectra from the model presented in this paper can be found at https://github.com/alexander-mead/hmcode.

  19. On finite volume effects in the chiral extrapolation of baryon masses

    CERN Document Server

    Lutz, M F M; Kobdaj, C; Schwarz, K

    2014-01-01

    We perform an analysis of the QCD lattice data on the baryon octet and decuplet masses based on the relativistic chiral Lagrangian. The baryon self energies are computed in a finite volume at next-to-next-to-next-to leading order (N^3LO), where the dependence on the physical meson and baryon masses is kept. The number of free parameters is reduced significantly down to 12 by relying on large-N_c sum rules. Altogether we describe accurately more than 220 data points from six different lattice groups, BMW, PACS-CS, HSC, LHPC, QCDSF-UKQCD and NPLQCD. Precise values for all counter terms relevant at N^3LO are predicted. In particular we extract a pion-nucleon sigma term of (39 +- 1) MeV and a strangeness sigma term of the nucleon of sigma_{sN} simeq (4 +- 1) MeV. The flavour SU(3) chiral limit of the baryon octet and decuplet masses is determined with ( 802 +- 4 ) MeV and (1103 +- 6) MeV. Detailed predictions for the baryon masses as currently evaluated by the ETM lattice QCD group are made.

  20. Analysis of the [53, l=2] Baryon Masses in the 1/N{sub c} Expansion

    Energy Technology Data Exchange (ETDEWEB)

    J.L. Goity; C.L. Schat; N.N. Scoccola

    2003-03-01

    The mass spectrum of the [56,{ell}=2] baryons is studied in the 1/N{sub c} expansion up to and including {Omicron}(1/N{sub c}) effects with SU(3) symmetry breaking implemented to first order. A total of eighteen mass relations result, several of which are tested with the available data.

  1. Charm baryons

    International Nuclear Information System (INIS)

    This paper contains a discussion of the spectrum of the lowest-lying charm baryons and review the experimental status of the masses of charm baryons and briefly comment on theoretical attempts to understand their spectroscopy. Lifetime measurements and lifetime hierarchies suggested by the interplay of various theoretical mechanisms contributing to the decay and semileptonic decays of charm baryons are discussed. It also treats exclusive nonleptonic charm baryon decays, where there are more data to be compared to theoretical modeling, and contains a summary and an outlook on future charm baryon experiments

  2. Masses and magnetic moments of triple heavy flavour baryons in hypercentral model

    Indian Academy of Sciences (India)

    Bhavin Patel; Ajay Majethiya; P C Vinodkumar

    2009-04-01

    Triple heavy flavour baryons are studied using the hypercentral description of the three-body system. The confinement potential is assumed as hypercentral Coulomb plus power potential with power index . The ground state ($J^{P} = \\dfrac{1}{2}^{+}$ and $\\dfrac{3}{2}^{+}$) masses of heavy flavour baryons are computed for different power index, starting from 0.5 to 2.0. The predicted masses are found to attain a saturated value with respect to variation in p beyond the power index > 1.0. Using the spin-flavour structure of the constituting quarks and by defining effective mass of the confined quarks within the baryons, the magnetic moments are computed with no additional free parameters.

  3. On the consistency of recent QCD lattice data of the baryon ground-state masses

    CERN Document Server

    Lutz, M F M

    2012-01-01

    In our recent analysis of lattice data of the BMW, LHPC and PACS-CS groups we determined a parameter set of the chiral Lagrangian that allows a simultaneous description of the baryon octet and decuplet masses as measured by those lattice groups. The results on the baryon spectrum of the HSC group were recovered accurately without their inclusion into our 6 parameter fit. We show that the same parameter set provides an accurate reproduction of the recent results of the QCDSF-UKQCD group probing the baryon masses at quite different quark masses. This shows a remarkable consistency amongst the different lattice simulations. With even more accurate lattice data in the near future it will become feasible to determine all low-energy parameters relevant at N$^3$LO.

  4. The Nc dependencies of baryon masses: Analysis with Lattice QCD and Effective Theory

    Energy Technology Data Exchange (ETDEWEB)

    Calle Cordon, Alvaro C. [JLAB; DeGrand, Thomas A. [University of Colorado; Goity, Jose L. [JLAB

    2014-07-01

    Baryon masses at varying values of Nc and light quark masses are studied with Lattice QCD and the results are analyzed in a low energy effective theory based on a combined framework of the 1/Nc and Heavy Baryon Chiral Perturbation Theory expansions. Lattice QCD results for Nc=3, 5 and 7 obtained in quenched calculations, as well as results for unquenched calculations for Nc=3, are used for the analysis. The results are consistent with a previous analysis of Nc=3 LQCD results, and in addition permit the determination of sub-leading in 1/Nc effects in the spin-flavor singlet component of the baryon masses as well as in the hyperfine splittings.

  5. Masses of charm and beauty baryons in the constituent quark model

    International Nuclear Information System (INIS)

    The masses of the ground state heavy baryons are studied using the hypercentral approach. The considered potential is a combination of Coulombic, linear confining and harmonic oscillator terms. An improved form of the hyperfine interaction and isospin dependent quark potential is introduced. By solving the Schroedinger equation for three particles system, we calculate the ground state masses of the baryons containing one, two and three heavy quarks. The obtained results are very close to the ones obtained in experiments or in the other works. (author)

  6. Narrow C IV absorption doublets on quasar spectra of the Baryon Oscillation Spectroscopic Survey

    CERN Document Server

    Zhi-fu, Chen; Luwenjia, Zhou; Yanmei, Chen

    2016-01-01

    In this paper, we extend our works of Papers I and II, which are assigned to systematically survey \\CIVab\\ narrow absorption lines (NALs) with \\zabs$\\ll$\\zem\\ on quasar spectra of the Baryon Oscillation Spectroscopic Survey (BOSS), to collect \\CIV\\ NALs with \\zabs$\\approx$\\zem\\ from blue to red wings of \\CIVwave\\ emission lines. Together with Papers I and II, we have collected a total number of 41,479 \\CIV\\ NALs with $1.4544\\le$\\zabs$\\le4.9224$ in surveyed spectral region redward of \\lya\\ until red wing of \\CIVwave\\ emission line. We find that the stronger \\CIV\\ NALs tend to be the more saturated absorptions, and associated systems (\\zabs$\\approx$\\zem) seem to have larger absorption strengths when compared to intervening ones (\\zabs$\\ll$\\zem). The redshift density evolution behavior of absorbers (the number of absorbers per redshift path) is similar to the history of the cosmic star formation. When compared to the quasar-frame velocity ($\\beta$) distribution of \\MgII\\ absorbers, the $\\beta$ distribution of \\C...

  7. Halo mass function: baryon impact, fitting formulae, and implications for cluster cosmology

    Science.gov (United States)

    Bocquet, Sebastian; Saro, Alex; Dolag, Klaus; Mohr, Joseph J.

    2016-03-01

    We use a set of hydrodynamical and dark matter-only (DMonly) simulations to calibrate the halo mass function (HMF). We explore the impact of baryons, propose an improved parametrization for spherical overdensity masses, and identify differences between our DMonly HMF and previously published HMFs. We use the Magneticum simulations, which are well suited because of their accurate treatment of baryons, high resolution, and large cosmological volumes of up to (3818 Mpc)3. Baryonic effects globally decrease the masses of galaxy clusters, which, at a given mass, results in a decrease of their number density. This effect vanishes at high redshift z ˜ 2 and for high masses M200 m ≳ 1014 M⊙. We perform cosmological analyses of three idealized approximations to the cluster surveys by the South Pole Telescope (SPT), Planck, and eROSITA. We pursue two main questions. (1) What is the impact of baryons? - for the SPT-like and the Planck-like samples, the impact of baryons on cosmological results is negligible. In the eROSITA-like case, however, neglecting the baryonic impact leads to an underestimate of Ωm by about 0.01, which is comparable to the expected uncertainty from eROSITA. (2) How does our DMonly HMF compare with previous work? - for the Planck-like sample, results obtained using our DMonly HMF are shifted by Δ(σ8) ≃ Δ(σ8(Ωm/0.27)0.3) ≃ 0.02 with respect to results obtained using the Tinker et al. fit. This suggests that using our HMF would shift results from Planck clusters towards better agreement with cosmic-microwave-background anisotropy measurements. Finally, we discuss biases that can be introduced through inadequate HMF parametrizations that introduce false cosmological sensitivity.

  8. Mass Spectra of Tetraselenafulvalenes, Diselenadithiafulvalenes and Tetrathiafulvalenes

    DEFF Research Database (Denmark)

    Andersen, Jan Rud; Egsgaard, Helge; Larsen, Elfinn;

    1978-01-01

    The mass spectra of 13 heterofulvalenes are reported. The spectra show great similarities within the selenium and within the sulphur series. The main difference between the selenium and the sulphur compounds results from the more facile loss of selenium compared with sulphur, and from the first...... fragmentation of the molecular ion, as the selenium fulvalenes lose an alkyne molecule, whereas the sulphur fulvalenes first lose an (SĊR) radical. An important feature of the spectra of the simple heterofulvalenes is the formation of a rearrangement ion by migration of a heteroatom. The mechanism was...

  9. Interpreting peptide mass spectra by VEMS

    DEFF Research Database (Denmark)

    Mathiesen, Rune; Lundsgaard, M.; Welinder, Karen G.;

    2003-01-01

    Most existing Mass Spectra (MS) analysis programs are automatic and provide limited opportunity for editing during the interpretation. Furthermore, they rely entirely on publicly available databases for interpretation. VEMS (Virtual Expert Mass Spectrometrist) is a program for interactive analysis...... of peptide MS/MS spectra imported in text file format. Peaks are annotated, the monoisotopic peaks retained, and the b-and y-ion series identified in an interactive manner. The called peptide sequence is searched against a local protein database for sequence identity and peptide mass. The report...... compares the calculated and the experimental mass spectrum of the called peptide. The program package includes four accessory programs. VEMStrans creates protein databases in FASTA format from EST or cDNA sequence files. VEMSdata creates a virtual peptide database from FASTA files. VEMSdist displays the...

  10. Masses and magnetic moments of heavy flavour baryons in hyper central model

    Science.gov (United States)

    Patel, Bhavin; Raiyz, Ajay Kumar; Vinodkumar, P. C.

    2008-05-01

    We employ the hyper central approach to study the masses and magnetic moments of the baryons constituting single charm and beauty quark. The confinement potential is assumed in the hyper central co-ordinates of the coulomb plus power potential form.

  11. Masses and magnetic moments of heavy flavour baryons in hyper central model

    CERN Document Server

    Patel, Bhavin; Vinodkumar, P C

    2008-01-01

    We employ the hyper central approach to study the masses and magnetic moments of the baryons constituting single charm and beauty quark. The confinement potential is assumed in the hyper central co-ordinates of the coulomb plus power potential form.

  12. Isospin splittings of meson and baryon masses from three-flavor lattice QCD+QED

    International Nuclear Information System (INIS)

    Lattice QCD simulations are now reaching a precision where isospin breaking effects become important. Previously, we have developed a program to systematically investigate the pattern of flavor symmetry beaking within QCD and successfully applied it to meson and baryon masses involving up, down and strange quarks. In this Letter we extend the calculations to QCD+QED and present our first results on isospin splittings in the pseudoscalar meson and baryon octets. In particular, we obtain Mπ+ - Mπ0=4.60(20) MeV and Mn-Mp=1.35(18) MeV.

  13. The low-lying baryon spectrum with two dynamical twisted mass fermions

    CERN Document Server

    Alexandrou, C; Carbonell, J; Drach, V; Guichon, P; Jansen, K; Korzec, T; Pène, O

    2009-01-01

    The masses of the low lying baryons are evaluated using two degenerate flavors of twisted mass sea quarks corresponding to pseudo scalar masses in the range of about 270-500 MeV. The strange valence quark mass is tuned to reproduce the mass of the kaon in the physical limit. The tree-level Symanzik improved gauge action is employed. We use lattices of spatial size 2.1 fm and 2.7 fm at two values of the lattice spacing with $r_0/a=5.22(2)$ and $r_0/a=6.61(3)$. We check for both finite volume and cut-off effects on the baryon masses. We performed a detailed study of the chiral extrapolation of the octet and decuplet masses using SU(2) $\\chi$PT. The lattice spacings determined using the nucleon mass at the physical point are consistent with the values extracted using the pion decay constant. We examine the issue of isospin symmetry breaking for the octet and decuplet baryons and its dependence on the lattice spacing. We show that in the continuum limit isospin breaking is consistent with zero, as expected. The b...

  14. High Mass Accuracy Phosphopeptide Identification Using Tandem Mass Spectra

    OpenAIRE

    Sadygov, Rovshan G.

    2012-01-01

    Phosphoproteomics is a powerful analytical platform for identification and quantification of phosphorylated peptides and assignment of phosphorylation sites. Bioinformatics tools to identify phosphorylated peptides from their tandem mass spectra and protein sequence databases are important part of phosphoproteomics. In this work, we discuss general informatics aspects of mass-spectrometry-based phosphoproteomics. Some of the specifics of phosphopeptide identifications stem from the labile nat...

  15. MOND Fit of Iocco, Pato, and Bertone (2015) Mean Baryonic Mass Distribution to Rotation Curve Data

    CERN Document Server

    Engelke, Philip D

    2015-01-01

    In a new release, Iocco, Pato, and Bertone in arXiv:1505.05181 analyze the consistency of Modified Newtonian Dynamics (MOND) with their compiled Milky Way data and baryonic mass distribution models. We contribute to the discussion by feeding the mean of the seven baryonic mass distribution models that they considered in their original paper into the MOND formula assuming the so-called simple interpolation function, and directly plotting these results on top of the compiled observational rotation curve data from their original paper. Although there is no reason to assume that the mean of the seven baryonic mass distribution models is more correct than any of the individual models, it is a reasonable choice to feed into the equations and one that is less subject to bias inherent in choosing an arbitrary individual model for the MOND analysis to compare to the data. We find that the mean baryonic model using MOND with the simple interpolation function provides a striking fit to the rotation curve observational d...

  16. The impact of baryons on massive galaxy clusters: halo structure and cluster mass estimates

    CERN Document Server

    Henson, Monique A; Kay, Scott T; McCarthy, Ian G; Schaye, Joop

    2016-01-01

    We use the BAHAMAS and MACSIS hydrodynamic simulations to quantify the impact of baryons on the mass distribution and dynamics of massive galaxy clusters, as well as the bias in X-ray and weak lensing mass estimates. These simulations use the sub-grid physics models calibrated in the BAHAMAS project, which include feedback from both supernovae and active galactic nuclei. They form a cluster population covering almost two orders of magnitude in mass, with more than 250 clusters with masses greater than $10^{15}\\,\\mathrm{M}_\\odot$ at $z=0$. We start by characterising the clusters in terms of their spin, shape and density profile, before considering the bias in both weak lensing and hydrostatic mass estimates. Whilst including baryonic effects leads to more spherical, centrally concentrated clusters, the median weak lensing mass bias is unaffected by the presence of baryons. In both the dark matter only and hydrodynamic simulations, the weak lensing measurements underestimate cluster masses by ${\\approx}10\\%$ fo...

  17. New lessons from the nucleon mass, lattice QCD and heavy baryon chiral perturbation theory

    OpenAIRE

    Walker-Loud, Andre

    2008-01-01

    I will review heavy baryon chiral perturbation theory for the nucleon delta degrees of freedom and then examine the recent dynamical lattice calculations of the nucleon mass from the BMW, ETM, JLQCD, LHP, MILC, NPLQCD, PACS-CS, QCDSF/UKQCD and RBC/UKQCD Collaborations. Performing the chiral extrapolations of these results, one finds remarkable agreement with the physical nucleon mass, from each lattice data set. However, a careful examination of the lattice data and the resulting extrapolatio...

  18. A TeV-scale model for neutrino mass, DM and baryon asymmetry

    OpenAIRE

    Aoki, Mayumi; Kanemura, Shinya; Seto, Osamu

    2009-01-01

    We discuss a model which would explain neutrino oscillation, dark matter, and baryon asymmetry of the Universe simultaneously by the physics at TeV scales. Tiny neutrino masses are generated at the three loop level due to the exact $Z_2$ symmetry, by which the stability of the dark matter candidate is also guaranteed. The extra Higgs doublet is required not only for the tiny neutrino masses but also for successful electroweak baryogenesis. The model provides various discriminative predictions...

  19. Octet-decuplet baryon mass splittings from self-consistent one-loop perturbation theory

    International Nuclear Information System (INIS)

    The bag model of confined relativistic quarks in chiral-invariant interaction with scalar, pseudoscalar, vector, and pseudovector mesons, as well as gluons, is used to calculate the masses and wave functions of the spin-1/2 baryon octet and spin-3/2 decuplet, using self-consistent Brillouin-Wigner bound state perturbation theory. Chiral symmetry breaking is invoked with the sigma model. SU (6) and SU (3) symmetries are broken by the experimental meson spectrum, and a strange quark mass. Mass corrections are calculated to one loop order, limited to the baryons of the octet and decuplet and the lowest lying mesons. Encouraging results are obtained, especially for the Δ - N and the Σ - Λ splittings. Convergence and stability have not been demonstrated, but are evidently improved by the self-consistency requirement. An initial parameter tuning gives a fit to all the octet and decuplet masses within ≤0.02 GeV, at the price of choosing the bag radius, the non-strange baryon input bag mass, and the strange quark mass. Even these small discrepancies can be dramatically reduced by fine-tuning the vector meson coupling and including an instanton contribution peculiar to the Λ. (orig.)

  20. Baryon masses from QCD current correlators at $T\

    OpenAIRE

    Eletsky, V. L.

    1994-01-01

    Correlation functions of QCD currents with quantum numbers of nucleon and $\\Delta$-isobar are considered at finite temperatures. Corrections of order $T^4$ to the correlators are calculated and interpreted in terms of thermal mass shifts using a QCD sum rules type of argument. In both cases the masses decrease with $T$.

  1. High Mass Accuracy Phosphopeptide Identification Using Tandem Mass Spectra

    Directory of Open Access Journals (Sweden)

    Rovshan G. Sadygov

    2012-01-01

    Full Text Available Phosphoproteomics is a powerful analytical platform for identification and quantification of phosphorylated peptides and assignment of phosphorylation sites. Bioinformatics tools to identify phosphorylated peptides from their tandem mass spectra and protein sequence databases are important part of phosphoproteomics. In this work, we discuss general informatics aspects of mass-spectrometry-based phosphoproteomics. Some of the specifics of phosphopeptide identifications stem from the labile nature of phosphor groups and expanded peptide search space. Allowing for modifications of Ser, Thr, and Tyr residues exponentially increases effective database size. High mass resolution and accuracy measurements of precursor mass-to-charge ratios help to restrict the search space of candidate peptide sequences. The higher-order fragmentations of neutral loss ions enhance the fragment ion mass spectra of phosphorylated peptides. We show an example of a phosphopeptide identification where accounting for fragmentation from neutral loss species improves the identification scores in a database search algorithm by 50%.

  2. The impact of baryonic physics on the subhalo mass function and implications for gravitational lensing

    CERN Document Server

    Despali, Giulia

    2016-01-01

    We investigate the impact of baryonic physics on the subhalo population by analyzing the results of two recent hydrodynamical simulations (EAGLE and Illustris), which have very similar configuration, but a different model of baryonic physics. We concentrate on haloes with a mass between $10^{12.5}$ and $10^{14}M_{\\odot}h^{-1}$ and redshift between 0.2 and 0.5, comparing with observational results and subhalo detections in early-type galaxy lenses. We compare the number and the spatial distribution of subhaloes in the fully hydro runs and in their dark matter only counterparts, focusing on the differences between the two simulations. We find that the presence of baryons reduces the number of subhaloes, especially at the low mass end ($\\leq 10^{10}M_{\\odot}h^{-1}$), by different amounts depending on the model. The variations in the subhalo mass function are strongly dependent on those in the halo mass function, which is shifted by the effect of stellar and AGN feedback: a lower number of low mass haloes availab...

  3. Baryon chiral perturbation theory withWilson fermions up to O(a2) and discretization effects of latest nf = 2 + 1 LQCD octet baryon masses

    International Nuclear Information System (INIS)

    We construct the chiral Lagrangians relevant in studies of the ground-state octet baryon masses up to O(a2) by taking into account discretization effects. We calculate the masses up to O(p4) in the extended-on-mass-shell scheme. As an application, we study the latest nf = 2+1 LQCD data on the ground-state octet baryon masses from the PACS-CS, QCDSF-UKQCD, HSC, and NPLQCD Collaborations. It is shown that the discretization effects for the studied LQCD simulations are at the order of 1-2 % for lattice spacings up to 0.15 fm and the pion mass up to 500 MeV. (orig.)

  4. SU(3)-flavour breaking in octet baryon masses and axial couplings

    OpenAIRE

    Carrillo-Serrano, Manuel E.; Cloët, Ian C.; Thomas, Anthony W.(CSSM and ARC Centre of Excellence for Particle Physics at the Tera-scale, School of Chemistry and Physics, University of Adelaide, Adelaide, SA 5005, Australia 1 1 http://www.physics.adelaide.edu.au/cssm .)

    2014-01-01

    The lightest baryon octet is studied within a covariant and confining Nambu--Jona-Lasinio model. By solving the relativistic Faddeev equations including scalar and axialvector diquarks, we determine the masses and axial charges for \\Delta S = 0 transitions. For the latter the degree of violation of SU(3) symmetry arising because of the strange spectator quark(s) is found to be up to 10%.

  5. In-Medium Effective Pion Mass from Heavy-Baryon Chiral Perturbation Theory

    CERN Document Server

    Park, T S; Min, D P; Park, Tae-Sun; Jung, Hong; Min, Dong-Pil

    2002-01-01

    Using heavy-baryon chiral perturbation theory, we have calculated all the diagrams up to two-loop order which contribute to the S-wave pion self-energy in symmetric nuclear matter. Some subtleties related to the definition of pion fields are discussed. The in-medium pion mass is turned out to be increased by only (6 - 7) per cents in normal nuclear matter density, without any off-shell ambiguity.

  6. Experimental evidence for narrow baryons in the mass range 1.0$\\le$ M $\\le$1.46 GeV

    CERN Document Server

    Tatischeff, B; Comets, M P; Courtat, P; Gacougnolle, R; Le Bornec, Y; Loireleux, E; Reide, F; Willis, N

    2003-01-01

    The reaction p p $\\to$ p ${\\pi^+}X$ was studied at different incident energies around T$_{p}$=2 GeV. Narrow baryonic structures were observed in the missing mass M$_{X}$ and in the invariant mass M$_{p\\pi^{+}}$. The masses of these structures are: 1004, 1044, 1094, 1136, 1173, 1249, 1277, and 1384 MeV (and possibly 1339 MeV). Some of them were also observed at the same masses in the missing mass spectra of the d p $\\to$ p p X reaction although with a weaker signature. Many checks were performed to make sure that these structures were not produced by experimental artifacts. Several narrow small amplitude peaks, were also extracted using already published photo-nucleon cross sections. The small widths of all these results, and the stability of the observed structures, regardless of the experiment, were used to conclude that they are genuine baryons which and not merely the consequence of dynamical rescatterings. These baryons cannot be associated with classical $q^{3}$ quark configurations. We associate them wi...

  7. A Study in Blue: The Baryon Content of Isolated Low Mass Galaxies

    CERN Document Server

    Bradford, Jeremy D; Blanton, Michael R

    2015-01-01

    We study the baryon content of low mass galaxies selected from the Sloan Digital Sky Survey (SDSS DR8), focusing on galaxies in isolated environments where the complicating physics of galaxy-galaxy interactions are minimized. We measure neutral hydrogen (HI) gas masses and line-widths for 148 isolated galaxies with stellar mass between $10^7$ and $10^{9.5} M_{\\odot}$. We compare isolated low mass galaxies to more massive galaxies and galaxies in denser environments by remeasuring HI emission lines from the Arecibo Legacy Fast ALFA (ALFALFA) survey 40% data release. All isolated low mass galaxies either have large atomic gas fractions or large atomic gas fractions cannot be ruled out via their upper limits. We measure a median atomic gas fraction of $f_{\\rm gas} = 0.82 \\pm 0.13$ for our isolated low mass sample with no systems below 0.30. At all stellar masses, the correlations between galaxy radius, baryonic mass and velocity width are not significantly affected by environment. Finally, we estimate a median b...

  8. Faddeev study of heavy baryon spectroscopy

    CERN Document Server

    Garcilazo, H; Vijande, J

    2007-01-01

    We investigate the structure of heavy baryons containing a charm or a bottom quark. We employ a constituent quark model successful in the description of the baryon-baryon interaction which is consistent with the light baryon spectra. We solve exactly the three-quark problem by means of the Faddeev method in momentum space. Heavy baryon spectrum shows a manifest compromise between perturbative and nonperturbative contributions. The flavor dependence of the one-gluon exchange is analyzed. We assign quantum numbers to some already observed resonances and we predict the first radial and orbital excitations of all states with $J=1/2$ or 3/2. We combine our results with heavy quark symmetry and lowest-order SU(3) symmetry breaking to predict the masses and quantum numbers of six still non-measured ground-state beauty baryons.

  9. Neutrino masses, dark matter and baryon asymmetry of the Universe

    CERN Document Server

    Ahriche, Amine

    2014-01-01

    In this work, we try to explain the neutrino mass and mixing data radiatively at three-loop by extending the standard model (SM) with two charged singlet scalars and three right handed (RH) neutrinos. Here, the lightest RH neutrino is a dark matter candidate that gives a relic density in agreement with the recent Planck data, the model can be consistent with the neutrino oscillation data, lepton flavor violating processes, the electroweak phase transition can be strongly first order; and the charged scalars may enhance the branching ratio $h\\rightarrow\\gamma\\gamma$, where as $h\\rightarrow\\gamma Z$ get can get few percent suppression. We also discuss the phenomenological implications of the RH neutrinos at the collider.

  10. Electrospray Ionization Mass Spectra of Dipeptide Derivatives

    Institute of Scientific and Technical Information of China (English)

    LUO, Zaigang; ZENG, Chengchu; YANG, Daoshan; HUANG, Yali; WANG, Fang; DU, Hongguang; HU, Liming

    2009-01-01

    Based on the structure of the HIV integrase core domain, dipeptide derivatives, as a type of HIV integrase in- hibitor, were synthesized, and their fragmentation pathways were investigated by electrospray ionization mass spec- trometry (ESI-MSN) in conjunction with tandem mass spectrometry (MS/MS). In order to better understand the fragmentation pathways, the MS2 and MS3 spectra of the title compound were obtained. The main fragmentation pathways occur by the cleavage of the C-CO bonds between N-(benzothiazol-2-yl)aminocarbonyl and methylene, NH-CO bonds between the NH groups and carbonyl groups. Electrospray ionization was proven to be a good method for the structural characterization and identification of this kind of compound.

  11. Baryon stopping and hadronic spectra in Pb-Pb collisions at 158 GeV/nucleon

    International Nuclear Information System (INIS)

    Baryon stopping and particle production in Pb+Pb collisions at 158 GeV/nucleon are studied as a function of the collision centrality using new proton, antiproton, charged kaon and charged pion production data measured with the NA49 experiment at the CERN Super Proton Synchrotron (SPS). Stopping, which is measured by the shift in rapidity of net protons or baryons from the initial beam rapidity, increases in more central collisions. This is expected from a geometrical picture of the collisions. The stopping data are quantitatively compared to models incorporating various mechanisms for stopping. In general, microscopic transport calculations which incorporate current theoretical models of baryon stopping or use phenomenological extrapolations from simpler systems overestimate the dependence of stopping on centrality. Approximately, the yield of produced pions scales with the number of nucleons participating in the collision. A small increase in yield beyond this scaling, accompanied by a small suppression in the yield of the fastest pions, reflects the variation in stopping with centrality. Consistent with the observations from central collisions of light and heavy nuclei at the SPS, the transverse momentum distributions of all particles are observed to become harder with increasing centrality. This effect is most pronounced for the heaviest particles. This hardening is discussed in terms of multiple scattering of the incident nucleons of one colliding nucleus as they traverse the other nucleus and in terms of rescattering within the system of produced particles

  12. Precision measurement of the mass and lifetime of the $\\Xi_b^0$ baryon

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Balagura, Vladislav; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; van den Brand, Johannes; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Busetto, Giovanni; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carranza-Mejia, Hector; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gavrilov, Gennadii; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Giani', Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gordon, Hamish; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; Hartmann, Thomas; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kaballo, Michael; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanciotti, Elisa; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Liu, Guoming; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lu, Haiting; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Manca, Giulia; Mancinelli, Giampiero; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Muresan, Raluca; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pazos Alvarez, Antonio; Pearce, Alex; Pellegrino, Antonio; Pepe Altarelli, Monica; Perazzini, Stefano; Perez Trigo, Eliseo; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Roa Romero, Diego; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruffini, Fabrizio; Ruiz, Hugo; Ruiz Valls, Pablo; Sabatino, Giovanni; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sapunov, Matvey; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrie, Mauro; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Seco, Marcos; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spradlin, Patrick; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szilard, Daniela; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; Voss, Helge; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wu, Suzhi; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander

    2014-01-01

    Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 $\\Xi_b^0\\to\\Xi_c^+\\pi^-$, $\\Xi_c^+\\to pK^-\\pi^+$ signal decays are reconstructed. From this sample, the first measurement of the $\\Xi_b^0$ baryon lifetime is made, relative to that of the $\\Lambda_b^0$ baryon. The mass differences $M(\\Xi_b^0)-M(\\Lambda_b^0)$ and $M(\\Xi_c^+)-M(\\Lambda_c^+)$ are also measured with precision more than four times better than the current world averages. The resulting values are $\\frac{\\tau_{\\Xi_b^0}}{\\tau_{\\Lambda_b^0}} = 1.006\\pm0.018\\pm0.010$, $M(\\Xi_b^0) - M(\\Lambda_b^0) = 172.44\\pm0.39\\pm0.17 MeV/c^2$, $M(\\Xi_c^+) - M(\\Lambda_c^+) = 181.51\\pm0.14\\pm0.10 MeV/c^2$, where the first uncertainty is statistical and the second is systematic. The relative rate of $\\Xi_b^0$ to $\\Lambda_b^0$ baryon production is measured to be $\\frac{f_{\\Xi_b^0}}{f_{\\Lambda_b^0}}\\frac{{\\cal{B}}(\\Xi_b^0\\to\\Xi_c^+\\pi^-)}{{\\cal{B}}(\\Lam...

  13. Separation of mass spectra of mixtures by factor analysis

    International Nuclear Information System (INIS)

    A method for the separation of mass spectra of mixtures is developed utilizing a factor analysis approach. It is shown to be possible, under certain conditions, to separate the data from mass spectra of mixtures into the mass spectra of the pure components and to give their respective concentrations. The technique is evaluated on an artifical data set and on data from mass spectra of mixtures previously reported in the literature. 6 tables

  14. Odor Impression Prediction from Mass Spectra

    Science.gov (United States)

    Nakamoto, Takamichi

    2016-01-01

    The sense of smell arises from the perception of odors from chemicals. However, the relationship between the impression of odor and the numerous physicochemical parameters has yet to be understood owing to its complexity. As such, there is no established general method for predicting the impression of odor of a chemical only from its physicochemical properties. In this study, we designed a novel predictive model based on an artificial neural network with a deep structure for predicting odor impression utilizing the mass spectra of chemicals, and we conducted a series of computational analyses to evaluate its performance. Feature vectors extracted from the original high-dimensional space using two autoencoders equipped with both input and output layers in the model are used to build a mapping function from the feature space of mass spectra to the feature space of sensory data. The results of predictions obtained by the proposed new method have notable accuracy (R≅0.76) in comparison with a conventional method (R≅0.61). PMID:27326765

  15. Quantum corrections to the masses of the octet and decuplet baryons in the SU(3) chiral quark soliton model

    CERN Document Server

    Akiyama, S; Akiyama, Satoru; Futami, Yasuhiko

    2006-01-01

    Mesonic fluctuations around the chiral solitons are investigated in the SU(3) chiral quark soliton model. Since the soliton takes the non-hedgehog shape for the hyperons and the hedgehog one for the non-hedgehog baryons in our approach, the fluctuations also change according to the baryonic state. The quantum corrections to the masses (the Casimir energies) are estimated for the octet and decuplet baryons. The lack of the confinement in this model demands the cutoff on the energy of the fluctuations. Under the assumption that the value of the cutoff energy is $2\\times$(the lightest constituent quark mass), these calculation reproduces the masses of the baryons within 15 % error.

  16. An extended Higgs sector for neutrino mass, dark matter and baryon asymmetry

    OpenAIRE

    Aoki, Mayumi; Kanemura, Shinya; Seto, Osamu

    2009-01-01

    In this talk, we discuss a TeV scale model which would explain neutrino oscillation, dark matter, and baryon asymmetry of the Universe simultaneously by the dynamics of the extended Higgs sector and TeV-scale right-handed neutrinos. By the imposed exact $Z_2$ symmetry, tiny neutrino masses are generated at the three loop level, and the stability of the dark matter candidate, an additional singlet scalar field, is guaranteed. The extra Higgs doublet is introduced not only for neutrino masses b...

  17. Stellar and total baryon mass fractions in groups and clusters since redshift 1

    CERN Document Server

    Giodini, S; Finoguenov, A; Pratt, G W; Böhringer, H; Leauthaud, A; Guzzo, L; Aussel, H; Bolzonella, M; Capak, P; Elvis, M; Hasinger, G; Ilbert, O; Kartaltepe, J S; Koekemoer, A M; Lilly, S J; McCracken, H J; Salvato, M; Sanders, D B; Scoville, N Z; Sasaki, S; Smolcic, V; Taniguchi, Y; Thompson, D

    2009-01-01

    We investigate if the discrepancy between estimates of the total baryon mass fraction obtained from observations of the cosmic microwave background (CMB) and of galaxy groups/clusters persists when a large sample of groups is considered. To this purpose, 91 candidate X-ray groups/poor clusters at redshift 0.1=5x10^{13} Msun to = 7 x 10^14 Msun. After consideration of a plausible contribution due to intra--cluster light (16% of the total stellar mass), and gas depletion through the hierarchical assembly process (10% of the gas mass), the estimated values of the total baryon mass fraction are still lower than the latest CMB measure of the same quantity (WMAP5), at a significance level of 3.7 sigma for groups of =5x10^13 Msun. The discrepancy decreases towards higher total masses, such that it is 1sigma at = 7x10^{14} Msun. We discuss this result in terms of non-gravitational processes such as feedback and filamentary heating.

  18. New lessons from the nucleon mass, lattice QCD and heavy baryon chiral perturbation theory

    CERN Document Server

    Walker-Loud, A

    2008-01-01

    I will review heavy baryon chiral perturbation theory for the nucleon delta degrees of freedom and then examine the recent dynamical lattice calculations of the nucleon mass from the BMW, ETM, JLQCD, LHP, MILC, NPLQCD, PACS-CS, QCDSF/UKQCD and RBC/UKQCD Collaborations. Performing the chiral extrapolations of these results, one finds remarkable agreement with the physical nucleon mass, from each lattice data set. However, a careful examination of the lattice data and the resulting extrapolation functions reveals some unexpected results, serving to highlight the significant challenges in performing chiral extrapolations of baryon quantities. All the N_f=2+1 dynamical results can be quantitatively described by theoretically unmotivated fit function linear in the pion mass with m_pi ~ 750 -190 MeV. When extrapolated to the physical point, the results are in striking agreement with the physical nucleon mass. I will argue that knowledge of each lattice datum of the nucleon mass is required at the 1-2% level, includ...

  19. Axial charges of hyperons and charmed baryons using Nf=2 +1 +1 twisted mass fermions

    Science.gov (United States)

    Alexandrou, C.; Hadjiyiannakou, K.; Kallidonis, C.

    2016-08-01

    The axial couplings of the low lying baryons are evaluated using a total of five ensembles of dynamical twisted mass fermion gauge configurations. The simulations are performed using the Iwasaki gauge action and two degenerate flavors of light quarks, and a strange and a charm quark fixed to approximately their physical values at two values of the coupling constant. The lattice spacings, determined using the nucleon mass, are a =0.082 fm and a =0.065 fm , and the simulations cover a pion mass in the range of about 210 MeV to 430 MeV. We study the dependence of the axial couplings on the pion mass in the range of about 210 MeV to 430 MeV as well as the SU(3) breaking effects as we decrease the light quark mass toward its physical value.

  20. Baryon masses at second order in large-N chiral perturbation theory

    International Nuclear Information System (INIS)

    We consider flavor breaking in the octet and decuplet baryon masses at second order in large-N chiral perturbation theory, where N is the number of QCD colors. We assume that 1/N∼1/NF∼ms/Λ>mu,d/Λ,αEM, where NF is the number of light quark flavors, and mu,d,s/Λ are the parameters controlling SU(NF) flavor breaking in chiral perturbation theory. We consistently include nonanalytic contributions to the baryon masses at orders mq3/2, m2qlnmq, and (mqlnmq)/N. The mq3/2 corrections are small for the relations that follow from SU(NF) symmetry alone, but the corrections to the large-N relations are large and have the wrong sign. Chiral power counting and large-N consistency allow a two-loop contribution at order m2qlnmq, and a nontrivial explicit calculation is required to show that this contribution vanishes. At second order in the expansion, there are eight relations that are nontrivial consequences of the 1/N expansion, all of which are well satisfied within the experimental errors. The average deviation at this order is 7 MeV for the ΔI=0 mass differences and 0.35 MeV for the ΔI≠0 mass differences, consistent with the expectation that the error is of order 1/N2∼10%. copyright 1996 The American Physical Society

  1. Gauge origin of baryon number conservation and suppressed neutrino masses from five dimensions

    International Nuclear Information System (INIS)

    We consider a 5D SUSY SU(3)cxSU(2)LxU(1)YxU(1) model compactified on an S(1)/Z2 orbifold. To cancel anomalies arising from the presence of U(1), we employ a Chern-Simons term and also chiral fields which could reside on the brane or in the bulk depending on the model. The presence of U(1) symmetry leads to baryon number conservation, gives rise to matter parity, and permits satisfactory neutrino masses and mixings even for a low fundamental scale. The brane Fayet-Iliopoulos D terms naturally break U(1), leaving N=1 SUSY unbroken in 4 dimensions

  2. A TeV scale model for neutrino mass, dark matter and baryon asymmetry

    OpenAIRE

    Aoki, Mayumi; Kanemura, Shinya; Seto, Osamu

    2009-01-01

    We discuss a TeV scale model which would explain neutrino oscillation, dark matter, and baryon asymmetry of the Universe simultaneously by the dynamics of the extended Higgs sector and TeV-scale right-handed neutrinos with imposed an exact $Z_2$ symmetry. Tiny neutrino masses are generated at the three loop level, a singlet scalar field is a candidate of dark matter, and a strong first order phase transition is realized for successful electroweak baryogenesis. The model provides various discr...

  3. Precision measurement of the mass and lifetime of the Ξ(b)(0) baryon.

    Science.gov (United States)

    Aaij, R; Adeva, B; Adinolfi, M; Affolder, A; Ajaltouni, Z; Akar, S; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; An, L; Anderlini, L; Anderson, J; Andreassen, R; Andreotti, M; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Badalov, A; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Batozskaya, V; Battista, V; Bay, A; Beaucourt, L; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Borsato, M; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brodzicka, J; Brook, N H; Brown, H; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Calabrese, R; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Cassina, L; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cenci, R; Charles, M; Charpentier, Ph; Chen, S; Cheung, S-F; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Corvo, M; Counts, I; Couturier, B; Cowan, G A; Craik, D C; Cruz Torres, M; Cunliffe, S; Currie, R; D'Ambrosio, C; Dalseno, J; David, P; David, P N Y; Davis, A; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Dijkstra, H; Donleavy, S; Dordei, F; Dorigo, M; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dreimanis, K; Dujany, G; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Ely, S; Esen, S; Evans, H-M; Evans, T; Falabella, A; Färber, C; Farinelli, C; Farley, N; Farry, S; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fiorini, M; Firlej, M; Fitzpatrick, C; Fiutowski, T; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Fu, J; Furfaro, E; Gallas Torreira, A; Galli, D; Gallorini, S; Gambetta, S; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gavardi, L; Gavrilov, G; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianelle, A; Giani', S; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Gotti, C; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grillo, L; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Han, X; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Henry, L; Hernando Morata, J A; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hoballah, M; Hombach, C; Hulsbergen, W; Hunt, P; Hussain, N; Hutchcroft, D; Hynds, D; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jalocha, J; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kaballo, M; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Karodia, S; Kelsey, M; Kenyon, I R; Ketel, T; Khanji, B; Khurewathanakul, C; Klaver, S; Kochebina, O; Kolpin, M; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucewicz, W; Kucharczyk, M; Kudryavtsev, V; Kurek, K; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Langhans, B; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Liles, M; Lindner, R; Linn, C; Lionetto, F; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lowdon, P; Lu, H; Lucchesi, D; Luo, H; Lupato, A; Luppi, E; Lupton, O; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Maratas, J; Marchand, J F; Marconi, U; Marin Benito, C; Marino, P; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martinez Vidal, F; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Mazurov, A; McCann, M; McCarthy, J; McNab, A; McNulty, R; McSkelly, B; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M-N; Moggi, N; Molina Rodriguez, J; Monteil, S; Morandin, M; Morawski, P; Mordà, A; Morello, M J; Moron, J; Morris, A-B; Mountain, R; Muheim, F; Müller, K; Muresan, R; Mussini, M; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neri, N; Neubert, S; Neufeld, N; Neuner, M; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Novoselov, A; O'Hanlon, D P; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Onderwater, G; Orlandea, M; Otalora Goicochea, J M; Owen, P; Oyanguren, A; Pal, B K; Palano, A; Palombo, F; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrignani, C; Pazos Alvarez, A; Pearce, A; Pellegrino, A; Pepe Altarelli, M; Perazzini, S; Perez Trigo, E; Perret, P; Perrin-Terrin, M; Pescatore, L; Pesen, E; Petridis, K; Petrolini, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Pistone, A; Playfer, S; Plo Casasus, M; Polci, F; Poluektov, A; Polycarpo, E; Popov, A; Popov, D; Popovici, B; Potterat, C; Price, E; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Rachwal, B; Rademacker, J H; Rakotomiaramanana, B; Rama, M; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Reichert, S; Reid, M M; Dos Reis, A C; Ricciardi, S; Richards, S; Rihl, M; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Rodrigues, A B; Rodrigues, E; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Rotondo, M; Rouvinet, J; Ruf, T; Ruffini, F; Ruiz, H; Ruiz Valls, P; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salustino Guimaraes, V; Sanchez Mayordomo, C; Sanmartin Sedes, B; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Saunders, D M; Savrie, M; Savrina, D; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Sepp, I; Serra, N; Serrano, J; Sestini, L; Seyfert, P; Shapkin, M; Shapoval, I; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, V; Shires, A; Silva Coutinho, R; Simi, G; Sirendi, M; Skidmore, N; Skwarnicki, T; Smith, N A; Smith, E; Smith, E; Smith, J; Smith, M; Snoek, H; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, M; Stahl, S; Steinkamp, O; Stenyakin, O; Stevenson, S; Stoica, S; Stone, S; Storaci, B; Stracka, S; Straticiuc, M; Straumann, U; Stroili, R; Subbiah, V K; Sun, L; Sutcliffe, W; Swientek, K; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szilard, D; Szumlak, T; T'Jampens, S; Teklishyn, M; Tellarini, G; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tomassetti, L; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Ustyuzhanin, A; Uwer, U; Vagnoni, V; Valenti, G; Vallier, A; Vazquez Gomez, R; Vazquez Regueiro, P; Vázquez Sierra, C; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vieites Diaz, M; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; de Vries, J A; Waldi, R; Wallace, C; Wallace, R; Walsh, J; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Websdale, D; Whitehead, M; Wicht, J; Wiedner, D; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wimberley, J; Wishahi, J; Wislicki, W; Witek, M; Wormser, G; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, Z; Xu, Z; Yang, Z; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L; Zvyagin, A

    2014-07-18

    Using a proton-proton collision data sample corresponding to an integrated luminosity of 3 fb(-1) collected by LHCb at center-of-mass energies of 7 and 8 TeV, about 3800 Ξ(b)(0) → Ξ(c)(+)π(-), Ξ(c)(+)) → pK(-)π(+) signal decays are reconstructed. From this sample, the first measurement of the Ξ(b)(0) baryon lifetime is made, relative to that of the Λ(b)(0) baryon. The mass differences M(Ξ(b)(0))-M(Λ(b)(0)) and M(Ξ(c)(+))-M(Λ(c)(+)) are also measured with precision more than 4 times better than the current world averages. The resulting values are τ(Ξ(b)(0))/τ(Λ)(b)(0)) = 1.006 ± 0.018 ± 0.010,M(Ξ(b)(0))-M(Λ(b)(0)) = 172.44 ± 0.39 ± 0.17 MeV/c(2),M(Ξ(c)(+))-M(Λ(c)(+)) = 181.51 ± 0.14 ± 0.10 MeV/c(2),where the first uncertainty is statistical and the second is systematic. The relative rate of Ξ(b)(0) to Λ(b)(0) baryon production is measured to be f(Ξ)(b)(0))/f(Λ)(b)(0))B(Ξ(b)(0) → Ξ(c)(+)π(-))/B(Λ(b)(0) → Λ(c)(+)π(-))B(Ξ(c)(+) → pK(-)π(+))/B(Λ(c)(+) → pK(-)}π(+)) = (1.88 ± 0.04 ± 0.03) × 10(-2),where the first factor is the ratio of fragmentation fractions, b → Ξ(b)(0) relative to b → Λ(b)(0). Relative production rates as functions of transverse momentum and pseudorapidity are also presented. PMID:25083633

  4. A holographic model for the baryon octet

    CERN Document Server

    Fang, Zhen

    2016-01-01

    By adopting the nonlinear realization of chiral symmetry, a holographic model for the baryon octet is proposed. The mass spectra of the baryon octet and their low-lying excited states are calculated, which show good consistency with experiments. The couplings of pion to nucleons are derived in two gauges and are shown to be equivalent with each other. It also shows that only derivative couplings of pion to nucleons appear in this holographic model. The coupling constant is then calculated.

  5. Neutron to proton mass difference, parton distribution functions and baryon resonances from dynamics on the Lie group u(3)

    DEFF Research Database (Denmark)

    Trinhammer, Ole

    We develop a hamiltonian framework on the Lie group u(3), which we call allospace and which is supposed to carry all the colour dynamics needed to describe the baryon spectrum. The energy eigenstates of our particular Schrödinger equation tends to predict realistically all certain baryon resonances...... in pPiMinus invariant mass in B decays. We give a controversial prediction of the relative neutron to proton mass difference 0.138 % as originating in period doublings of certain parametric states. The group space dynamics communicates with real space via the exterior derivative which projects out...

  6. Systematic errors in the measurement of neutrino masses due to baryonic feedback processes: Prospects for stage IV lensing surveys

    CERN Document Server

    Natarajan, Aravind; Battaglia, Nicholas; Trac, Hy

    2014-01-01

    We examine the importance of baryonic feedback effects on the matter power spectrum on small scales, and the implications for the precise measurement of neutrino masses through gravitational weak lensing. Planned large galaxy surveys such as the Large Synoptic Sky Telescope (LSST) and Euclid are expected to measure the sum of neutrino masses to extremely high precision, sufficient to detect non-zero neutrino masses even in the minimal mass normal hierarchy. We show that weak lensing of galaxies while being a very good probe of neutrino masses, is extremely sensitive to baryonic feedback processes. We use publicly available results from the Overwhelmingly Large Simulations (OWLS) project to investigate the effects of active galactic nuclei feedback, the nature of the stellar initial mass function, and gas cooling rates, on the measured weak lensing shear power spectrum. Using the Fisher matrix formalism and priors from CMB+BAO data, we show that when one does not account for feedback, the measured neutrino mas...

  7. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: weighing the neutrino mass using the galaxy power spectrum of the CMASS sample

    OpenAIRE

    Zhao, G. -B.; Saito, S.; Percival, W J; Ross, A. J.; Montesano, F.; M. Viel(INAF-Osservatorio Astronomico di Trieste, Italy); Schneider, D. P.; Manera, M; Miralda-Escude, J.; Palanque-Delabrouille, N.; Ross, N. P.; Samushia, L.; Sanchez, A. G.; Swanson, M. E. C.; D. Thomas

    2013-01-01

    We measure the sum of the neutrino particle masses using the three-dimensional galaxy power spectrum of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 9 (DR9) CMASS galaxy sample. Combined with the cosmic microwave background (CMB), supernova (SN) and additional baryonic acoustic oscillation (BAO) data, we find upper 95 percent confidence limits of the neutrino mass $\\Sigma m_{\

  8. How to probe the infrared quark mass with parity quartets in the high baryon spectrum

    CERN Document Server

    Bicudo, P; Van Cauteren, T; Llanes-Estrada, Felipe J

    2009-01-01

    By current theoretical understanding, spontaneous chiral symmetry breaking enhances the quark masses in the infrared, and thus generates most of the visible mass in our universe, i. e. the mass of the nucleons, while simultaneously removing chiral symmetry from the lowest states of the light hadron spectrum. We first show that three-quark states naturally group into quartets (with two states of each parity), split into two parity doublets, all splittings decreasing high in the spectrum. We then present a first theoretical computation of the spectrum of high-J excited baryons with a chiral invariant quark model. We propose that a measurement of masses of high-partial wave Delta resonances with an accuracy of 50 MeV should be sufficient to unambiguously establish the approximate degeneracy, and learn how to probe the running quark mass in the mid-infrared power-law regime, thanks to an ultrarelativistic expansion of the quark spinors. Such precision, if challenging, can be reached thanks to experimental progres...

  9. $\\omega$-Nucleon Interaction and Nucleon Mass in Dense Baryonic Matter

    CERN Document Server

    Paeng, Won-Gi; Rho, Mannque; Sasaki, Chihiro

    2013-01-01

    The dilaton-limit fixed point and the scaling properties of hadrons in the close vicinity of the fixed point in dense baryonic matter uncovered in hidden local symmetry implemented with spontaneously broken scale symmetry are shown to reveal a surprisingly intricate interplay, hitherto unsuspected, between the origin of the bulk of proton mass and the renormalization-group flow of the $\\omega$-nuclear interactions. This rends a theoretical support to the previous (phenomenologically) observed correlation between the dropping nucleon mass and the behavior of the $\\omega$-nuclear interactions in dense matter described in terms of half skyrmions that appear at a density denoted $n_{1/2}$ in skyrmion crystals. The role of the $\\omega$-meson degree of freedom in the source for nucleon mass observed in this paper is highly reminiscent of its important role in the skyrmion description of nucleon mass in hidden local symmetric theory. One of the most notable novel results found in this paper is that the nucleon mass ...

  10. The Spectrum of the Baryon Masses in a Self-consistent SU(3) Quantum Skyrme Model

    CERN Document Server

    Jurciukonis, Darius; Regelskis, Vidas

    2012-01-01

    The semiclassical SU(3) Skyrme model is traditionally considered as describing a rigid quantum rotator with the profile function being fixed by the classical solution of the corresponding SU(2) Skyrme model. In contrast, we go beyond the classical profile function by quantizing the SU(3) Skyrme model canonically. The quantization of the model is performed in terms of the collective coordinate formalism and leads to the establishment of purely quantum corrections of the model. These new corrections are of fundamental importance. They are crucial in obtaining stable quantum solitons of the quantum SU(3) Skyrme model, thus making the model self-consistent and not dependent on the classical solution of the SU(2) case. We show that such a treatment of the model leads to a family of stable quantum solitons that describe the baryon octet and decuplet and reproduce the experimental values of their masses.

  11. Spherical bootstrap calculation of qqq-baryon and multiquark-hadron masses

    International Nuclear Information System (INIS)

    Recently a way of implementing the dual-topological unitarization program has been found, in which baryons and other multiquark hadrons are put on the sphere and appear at the same topological-complexity level as ordinary anti-qq mesons. This permits one to have a lowest-order 'spherical bootstrap', within which unitarity, duality and crossing can be consistently satisfied. In the present paper, this framework to calculate hadron masses has been used by imposing duality on an infinite sum of ladder graphs generated from spherical unitarity. By making a certain simple dynamical approximation, an explicit generic Regge-trajectory formula is derived for any given process. If one then makes certain reasonable dynamical assumptions and requires simultaneous consistency for entire sets of processes, it is possible to calculate the masses of all the lowest states and the Regge trajectories associated with each of them. The only arbitrary parameter is the mass of the rho which merely serves to set the mass scale

  12. Interpretation of Tandem Mass Spectrometry (MSMS) Spectra for Peptide Analysis

    DEFF Research Database (Denmark)

    Hjernø, Karin; Højrup, Peter

    2015-01-01

    The aim of this chapter is to give a short introduction to peptide analysis by mass spectrometry (MS) and interpretation of fragment mass spectra. Through examples and guidelines we demonstrate how to understand and validate search results and how to perform de novo sequencing based on the often...... very complex fragmentation pattern obtained by tandem mass spectrometry (also referred to as MSMS). The focus is on simple rules for interpretation of MSMS spectra of tryptic as well as non-tryptic peptides....

  13. Constraint of baryon asymmetry on grand unified theories and X-X/sup c/ mass splitting scenario for baryon number generation

    International Nuclear Information System (INIS)

    An important constraint on Grand Unified Theories (GUTs) is the correct estimate of Baryon Asymmetry of the Universe (BAU), in the standard scenario and with a conventional energy-temperature behavior. This is proportional to the intrinsic maximal CP-violation at superhigh energies, which as the lore goes barely accounts for the observed baryon-to-entropy ratio. This is further controlled by some global features: a global symmetry, if broken inadequately, can unduely suppress the estimate and the problem is how to overwhelm the suppression. Illustrated variously, this possibility of the group-theoretical constraint is also contrasted with that of a dynamical constraint. Attention is focused on a specific constraint, that arising from the broken group-C invariance (C = Charge-conjugation), note its implications on neutrino mass and examine, in particular, how to overwhelm the resulting suppression by splitting the mass of the decaying scalar X from its charge conjugate X/sup c/ in an SO(10) theory with Written's mechanism for neutrino mass. This possibility of X-X/sup c/ mass-splitting was envisaged in the previous general study (with Haber and Segre) whose important conclusions are reviewed: some general observations on spontaneously unbroken C-invariance and a solution to the problem of BAU, in spontaneously broken C-invariant theories, by allowing no overlap between the contributions form the free-decays of X-anti X and S/sup c/-anti X/sup c/ pairs through nu-N/sup c/ mass splitting greater than or equal to m (X). Only the following details are now added

  14. Precision measurement of the mass and lifetime of the $\\Xi_b^-$ baryon

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; 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Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; 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    2014-01-01

    We report on measurements of the mass and lifetime of the $\\Xi_b^-$ baryon using about 1800 $\\Xi_b^-$ decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0 fb$^{-1}$ collected by the LHCb experiment. The decays are reconstructed in the $\\Xi_b^-\\to\\Xi_c^0\\pi^-$, $\\Xi_c^0\\to pK^-K^-\\pi^+$ channel and the mass and lifetime are measured using the $\\Lambda_b^0\\to\\Lambda_c^+\\pi^-$ mode as a reference. We measure \\begin{equation} \\ M(\\Xi_b^-)-M(\\Lambda_b^0)=178.36\\pm0.46\\pm0.16~MeV/c^2, \\end{equation} \\begin{equation} \\frac{^\\tau\\Xi_b^-} {^\\tau\\Lambda_b^0}=1.089\\pm0.026\\pm0.011, \\end{equation} where the uncertainties are statistical and systematic, respectively. These results lead to a factor of two better precision on the $\\Xi_b^-$ mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations.

  15. Precision measurement of the mass and lifetime of the Ξb⁻ baryon.

    Science.gov (United States)

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Pietrzyk, B; Pilař, T; Pinci, D; Pistone, A; Playfer, S; Plo Casasus, M; Polci, F; Poluektov, A; Polycarpo, E; Popov, A; Popov, D; Popovici, B; Potterat, C; Price, E; Price, J D; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Rachwal, B; Rademacker, J H; Rakotomiaramanana, B; Rama, M; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redi, F; Reichert, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, S; Rihl, M; Rinnert, K; Rives Molina, V; Robbe, P; Rodrigues, A B; Rodrigues, E; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Rotondo, M; Rouvinet, J; Ruf, T; Ruiz, H; Ruiz Valls, P; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salustino Guimaraes, V; Sanchez Mayordomo, C; Sanmartin Sedes, B; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sarti, A; Satriano, C; Satta, A; Saunders, D M; Savrina, D; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schubiger, M; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Semennikov, A; Sepp, I; Serra, N; Serrano, J; Sestini, L; Seyfert, P; Shapkin, M; Shapoval, I; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, V; Shires, A; Silva Coutinho, R; Simi, G; Sirendi, M; Skidmore, N; Skillicorn, I; Skwarnicki, T; Smith, N A; Smith, E; Smith, E; Smith, J; Smith, M; Snoek, H; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Spradlin, P; Sridharan, S; Stagni, F; Stahl, M; Stahl, S; Steinkamp, O; Stenyakin, O; Stevenson, S; Stoica, S; Stone, S; Storaci, B; Stracka, S; Straticiuc, M; Straumann, U; Stroili, R; Subbiah, V K; Sun, L; Sutcliffe, W; Swientek, K; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Tellarini, G; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Todd, J; Tolk, S; Tomassetti, L; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Trisovic, A; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Ustyuzhanin, A; Uwer, U; Vacca, C; Vagnoni, V; Valenti, G; Vallier, A; Vazquez Gomez, R; Vazquez Regueiro, P; Vázquez Sierra, C; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vieites Diaz, M; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; de Vries, J A; Waldi, R; Wallace, C; Wallace, R; Walsh, J; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Websdale, D; Whitehead, M; Wicht, J; Wiedner, D; Wilkinson, G; Williams, M P; Williams, M; Wilschut, H W; Wilson, F F; Wimberley, J; Wishahi, J; Wislicki, W; Witek, M; Wormser, G; Wotton, S A; Wright, S; Wyllie, K; Xie, Y; Xing, Z; Xu, Z; Yang, Z; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L

    2014-12-12

    We report on measurements of the mass and lifetime of the Ξ(b)⁻ baryon using about 1800 Ξ(b)⁻ decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0  fb⁻¹ collected by the LHCb experiment. The decays are reconstructed in the Ξ(b)⁻→Ξ(c)⁰π⁻, Ξ(c)⁰→pK⁻K⁻π⁺ channel and the mass and lifetime are measured using the Λ(b)⁰→Λ(c)⁺π⁻ mode as a reference. We measure M(Ξ(b)⁻)-M(Λ(b)⁰)=178.36±0.46±0.16  MeV/c², (τ(Ξ(b)⁻)/τ(Λ(b)⁰)=1.089±0.026±0.011, where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the Ξ(b)⁻ mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations. PMID:25541768

  16. Baryon chiral perturbation theory with Wilson fermions up to $\\mathcal{O}(a^2)$ and discretization effects of latest $n_f=2+1$ LQCD octet baryon masses

    OpenAIRE

    Ren, Xiu-Lei; Geng, Li-Sheng; Meng, Jie

    2013-01-01

    We construct the chiral Lagrangians relevant in studies of the ground-state octet baryon masses up to O(a2) by taking into account discretization effects. We calculate the masses up to O(p4) in the extended-on-mass-shell scheme. As an application, we study the latest nf=2+1 LQCD data on the ground-state octet baryon masses from the PACS-CS, QCDSF-UKQCD, HSC, and NPLQCD Collaborations. It is shown that the discretization effects for the studied LQCD simulations are at the order of 1–2 % for la...

  17. Measurement of the mass and lifetime of the $\\Omega_b^-$ baryon

    CERN Document Server

    Aaij, Roel; Adeva, Bernardo; Adinolfi, Marco; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baker, Sophie; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borgheresi, Alessio; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Boubdir, Meriem; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chatzikonstantinidis, Georgios; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chobanova, Veronika; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Aguiar Francisco, Oscar; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Demmer, Moritz; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dungs, Kevin; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farley, Nathanael; Farry, Stephen; Fay, Robert; Fazzini, Davide; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fohl, Klaus; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Garsed, Philip John; Gascon, David; Gaspar, Clara; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc

    2016-01-01

    A proton-proton collision data sample, corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by LHCb at $\\sqrt{s}=7$ and 8 TeV, is used to reconstruct $63\\pm9$ $\\Omega_b^-\\to\\Omega_c^0\\pi^-$, $\\Omega_c^0\\to pK^-K^-\\pi^+$ decays. Using the $\\Xi_b^-\\to\\Xi_c^0\\pi^-$, $\\Xi_c^0\\to pK^-K^-\\pi^+$ decay mode for calibration, the lifetime ratio and absolute lifetime of the $\\Omega_b^-$ baryon are measured to be \\begin{align*} \\frac{\\tau_{\\Omega_b^-}}{\\tau_{\\Xi_b^-}} &= 1.11\\pm0.16\\pm0.03, \\\\ \\tau_{\\Omega_b^-} &= 1.78\\pm0.26\\pm0.04\\pm0.05~{\\rm ps}, \\end{align*} where the uncertainties are statistical, systematic and from the calibration mode (for $\\tau_{\\Omega_b^-}$ only). A measurement is also made of the mass difference, $m_{\\Omega_b^-}-m_{\\Xi_b^-}$, and the corresponding $\\Omega_b^-$ mass, which yields \\begin{align*} m_{\\Omega_b^-}-m_{\\Xi_b^-} &= 247.4\\pm3.2\\pm0.5~{\\rm MeV}/c^2, \\\\ m_{\\Omega_b^-} &= 6045.1\\pm3.2\\pm 0.5\\pm0.6~{\\rm MeV}/c^2. \\end{align*} These results are consistent with p...

  18. Proton Mass, Topology Change and Tensor Forces in Compressed Baryonic Matter

    CERN Document Server

    Rho, Mannque

    2013-01-01

    This is a summary of the talks I gave at Korean Physical Society meeting (April 26, 2012, Daejeon, Korea) and the 4th Asian Triangle Heavy Ion Conference (ATHIC) (November 14, 2012, Pusan, Korea). They are based on the series of work done at Hanyang University in the World Class University III Program under the theme of "From Dense Matter to Compact Stars." The program was conceived and executed to understand highly compressed baryonic matter in anticipation of the forthcoming RIB machine "RAON" which is in construction in the Institute for Basic Science (IBS) in Korea. The problems treated ranged from the origin of the proton mass, topological structure of barynic matter, chiral symmetry and conformal symmetry to the EoS of nuclear matter and dense neutron-rich matter and to the maximum mass of neutron stars. The results obtained are new and intriguing and could have an impact on the novel structure of dense matter to be probed in the accelerators "RAON," FAIR etc. and in compact stars.

  19. Cosmological constraints from the evolution of the cluster baryon mass function at z similar to 0.5

    DEFF Research Database (Denmark)

    Vikhlinin, A.; Voevodkin, A.; Mullis, C.R.; VanSpeybroeck, L.; Quintana, H.; McNamara, B.R.; Gioia, I.; Hornstrup, Allan; Henry, J.P.; Forman, W.R.; Jones, C.

    2003-01-01

    We present a new method for deriving cosmological constraints based on the evolution of the baryon mass function of galaxy clusters and implement it using 17 distant clusters from our 160 deg(2) ROSAT survey. The method uses the cluster baryon mass as a proxy for the total mass, thereby avoiding...... the large uncertainties of the M-tot-T or M-tot-L-X relations used in all previous studies. Instead, we rely on a well-founded assumption that the M-b/M-tot ratio is a universal quantity, which should result in a much smaller systematic uncertainty. Taking advantage of direct and accurate Chandra...... measurements of the gas masses for distant clusters, we find strong evolution of the baryon mass function between z > 0.4 and the present. The observed evolution defines a narrow band in the Omega(m)-Lambda plane, Omega(m) + 0.23Lambda = 0.41 +/- 0.10 at 68% confidence, which intersects with constraints from...

  20. Peptide de novo sequencing of mixture tandem mass spectra

    DEFF Research Database (Denmark)

    Gorshkov, Vladimir; Hotta, Stéphanie Yuki Kolbeck; Braga, Thiago Verano;

    2016-01-01

    complementary b-, y-ions to each precursor peptide mass, which allowed the creation of virtual spectra containing sequence specific fragment ions of each co-isolated peptide. Deconvolution processing resulted in equally efficient identification rates but increased the absolute number of correctly sequenced...... peptides. The improvement was in the range of 20–35% additional peptide identifications for a HeLa lysate sample. Some correct sequences were identified only using unprocessed spectra; however, the number of these was lower than those where improvement was obtained by mass spectral deconvolution. Tight......The impact of mixture spectra deconvolution on the performance of four popular de novo sequencing programs was tested using artificially constructed mixture spectra as well as experimental proteomics data. Mixture fragmentation spectra are recognized as a limitation in proteomics because they...

  1. A new matching algorithm for high resolution mass spectra

    DEFF Research Database (Denmark)

    Hansen, Michael Edberg; Smedsgaard, Jørn

    2004-01-01

    We present a new matching algorithm designed to compare high-resolution spectra. Whereas existing methods are bound to compare fixed intervals of ion masses, the accurate mass spectrum (AMS) distance method presented here is independent of any alignment. Based on the Jeffreys-Matusitas (JM...... accurate mass spectra from an analysis of extracts of 80 isolates representing the nine closely related species in the Penicillium series Viridicata. Using this algorithm we can obtain a retrieval performance of approximate to97-98% that is comparable with the best of the existing methods (e.g., the dot......) distance, a difference between observed peaks across pairs of spectra can be calculated, and used to find a unique correspondence between the peaks. The method takes into account that there may be differences in resolution of the spectra. The algorithm is used for indexing in a database containing 80...

  2. Strange baryon production in Pb-Pb interactions at CERN SPS

    CERN Document Server

    Sándor, L; Bacon, P A; Badalà, A; Barbera, R; Belogianni, A; Bhasin, A; Bloodworth, I J; Bombara, M; Bruno, G E; Bull, S A; Caliandro, R; Campbell, M; Carena, W; Carrer, N; Clarke, R F; Dainese, A; De Haash, A P; De Rijke, P; Di Bari, D; Di Liberto, S; Divià, R; Elia, D; Evans, D; Fanebust, K; Fayazzadeh, F; Feofilov, G A; Fini, R A; Ganoti, P; Ghidini, B; Grella, G; Helstrup, H; Henriquez, M; Holme, A K; Jacholkowski, A; Jones, G T; Jovanovic, P; Jusko, A; Kamermans, R; Kinson, J B; Knudson, K; Kolojvari, A A; Kondratiev, V; Králik, I; Kravcakova, A; Kuijer, P; Lenti, V; Lietava, R; Løvhøiden, G; Manzari, V; Martinská, G; Mazzoni, M A; Meddi, F; Michalon, A; Morando, M; Nappi, E; Navach, F; Norman, P I; Palmeri, A; Pappalardo, G S; Pastircák, B; Pisút, J; Pisútová, N; Posa, F; Quercigh, Emanuele; Riggi, F; Röhrich, D; Romano, G; Safarík, K; Schillings, E; Segato, G F; Sené, M; Sené, R; Snoeys, W; Soramel, F; Spyropoulou-Stassinaki, M; Staroba, P; Toulina, T A; Turrisi, R; Tveter, T S; Urbán, J; Valiev, F F; Van den Brink, A; Van de Ven, P; Vyvre, P V; van Eijndhoven, N; Van Hunen, J; Vascotto, A; Vik, T; Villalobos Baillie, O; Vinogradov, L; Virgili, T; Votruba, M F; Vrláková, J; Závada, P

    2004-01-01

    Recent results on strange baryon and antibaryon production in Pb-Pb collisions at 160 GeV per nucleon from the NA57 experiment are reported. Strangeness enhancements and the transverse mass spectra properties are described.

  3. First results of baryon interactions from lattice QCD with physical masses (1) -- General overview and two-nucleon forces --

    CERN Document Server

    Doi, Takumi; Gongyo, Shinya; Hatsuda, Tetsuo; Ikeda, Yoichi; Inoue, Takashi; Iritani, Takumi; Ishii, Noriyoshi; Miyamoto, Takaya; Murano, Keiko; Nemura, Hidekatsu; Sasaki, Kenji

    2015-01-01

    We present the lattice QCD studies for baryon-baryon interactions for the first time with (almost) physical quark masses. $N_f = 2+1$ gauge configurations are generated with the Iwasaki gauge action and nonperturbatively $O(a)$-improved Wilson quark action with stout smearing on the lattice of $(96 a)^4 \\simeq (8.2 {\\rm fm})^4$ with $a \\simeq 0.085$ fm, where $m_\\pi \\simeq 146$ MeV and $m_K \\simeq 525$ MeV. Baryon forces are calculated from Nambu-Bethe-Salpeter (NBS) correlation functions using the time-dependent HAL QCD method. In this report, we first give the general overview of the theoretical frameworks essential to the physical point calculation of baryon forces. We then present the numerical results for the two-nucleon central and tensor forces in $^3S_1$-$^3D_1$ coupled channel and the central force in $^1S_0$ channel. In particular, a clear signal is obtained for the tensor force.

  4. Evolution of the Blue Luminosity-to-Baryon Mass Ratio of Clusters of Galaxies

    CERN Document Server

    Shimasaku, K

    2000-01-01

    We derive the ratio of total blue luminosity to total baryon mass, LB/Mb, for massive (Mgas at the Abell radius is \\ge 1 \\times 10^{13} h^{-2.5} \\Msolar) clusters of galaxies up to z \\simeq 1 from the literature. Twenty-two clusters in our sample are at z > 0.1. Assuming that the relative mix of hot gas and galaxies in clusters does not change during cluster evolution, we use LB/Mb to probe the star formation history of the galaxy population as a whole in clusters. We find that LB/Mb of clusters increases with redshift from LB/Mb=0.024 (solar units) at z = 0 to \\simeq 0.06 at z=1, indicating a factor of 2-3 brightening (we assume H0=70 km/s/Mpc). This amount of brightening is almost identical to the brightening of the M/LB ratio of early-type galaxies in clusters at 0.02 \\le z \\le 0.83 reported by van Dokkum et al. (1998). We compare the observed brightening of LB/Mb with luminosity evolution models for the galaxy population as a whole, changing the e-folding time of star formation brightening, while models w...

  5. Negative Parity 70-plet Baryon Masses in the 1/N{sub c} Expansion

    Energy Technology Data Exchange (ETDEWEB)

    Jose Goity; Carlos L. Schat; Norberto N. Scoccola

    2002-08-01

    The masses of the negative parity SU(6) 70-plet baryons are analyzed in the 1/N{sub c} expansion to order 1/N{sub c} and to first order in SU(3) breaking. At this level of precision there are twenty predictions. Among them there are the well known Gell-Mann Okubo and equal spacing relations, and four new relations involving SU(3) breaking splittings in different SU(3) multiplets. Although the breaking of SU(6) symmetry occurs at zeroth order in 1/N{sub c}, it turns out to be small. The dominant source of the breaking is the hyperfine interaction which is of order 1/N{sub c}. The spin-orbit interaction, of zeroth order in 1/N{sub c}, is entirely fixed by the splitting between the singlet states A(1405) and A(1520), and the spin-orbit puzzle is resolved by the presence of other zeroth order operators involving flavor exchange.

  6. Automated data processing of high-resolution mass spectra

    DEFF Research Database (Denmark)

    Hansen, Michael Adsetts Edberg; Smedsgaard, Jørn

    infusion of crude extracts into the source taking advantage of the high sensitivity, high mass resolution and accuracy and the limited fragmentation. Unfortunately, there has not been a comparable development in the data processing techniques to fully exploit gain in high resolution and accuracy of the...... massive amounts of data. We present an automated data processing method to quantitatively compare large numbers of spectra from the analysis of complex mixtures, exploiting the full quality of high-resolution mass spectra. By projecting all detected ions - within defined intervals on both the time and...... mass axis on to a fixed one-dimensional array, we obtain a vector that can be used directly as input in multivariate statistics or library search methods. We demonstrate that both cluster- and discriminant analysis as well as PCA (and related methods) can be applied directly on mass spectra from direct...

  7. Hyperon and charmed baryon masses and nucleon excited states from lattice QCD

    CERN Document Server

    Alexandrou, Constantia

    2014-01-01

    We discuss the status of current dynamical lattice QCD simulations in connection to the emerging results on the strange and charmed baryon spectrum, excited states of the nucleon and the investigation of the structure of scalar mesons.

  8. A further study of the Frampton-Glashow-Yanagida model for neutrino masses, flavor mixing and baryon number asymmetry

    OpenAIRE

    Zhang, Jue; Zhou, Shun

    2015-01-01

    In light of the latest neutrino oscillation data, we revisit the minimal scenario of type-I seesaw model, in which only two heavy right-handed Majorana neutrinos are introduced to account for both tiny neutrino masses and the baryon number asymmetry in our Universe. In this framework, we carry out a systematic study of the Frampton-Glashow-Yanagida ansatz by taking into account the renormalization-group running of neutrino mixing parameters and the flavor effects in leptogenesis. We demonstra...

  9. Spectroscopy of beautiful baryons

    Energy Technology Data Exchange (ETDEWEB)

    Caloi, R.; Gentile, S.; Mignani, R. (Rome Univ. (Italy). Ist. di Fisica)

    1980-09-20

    By assuming a non-relativistic quark model, an estimate of the masses of the low-lying (non-strange and non-charmed) beautiful baryons is given. Electromagnetic mass splittings of the same baryons are also discussed in some detail.

  10. Neutrino mass, dark matter, and Baryon asymmetry via TeV-scale physics without fine-tuning.

    Science.gov (United States)

    Aoki, Mayumi; Kanemura, Shinya; Seto, Osamu

    2009-02-01

    We propose an extended version of the standard model, in which neutrino oscillation, dark matter, and the baryon asymmetry of the Universe can be simultaneously explained by the TeV-scale physics without assuming a large hierarchy among the mass scales. Tiny neutrino masses are generated at the three-loop level due to the exact Z2 symmetry, by which the stability of the dark matter candidate is guaranteed. The extra Higgs doublet is required not only for the tiny neutrino masses but also for successful electroweak baryogenesis. The model provides discriminative predictions especially in Higgs phenomenology, so that it is testable at current and future collider experiments. PMID:19257506

  11. Neutrino mass, Dark Matter and Baryon Asymmetry via TeV-Scale Physics without Fine-Tuning

    OpenAIRE

    Aoki, Mayumi; Kanemura, Shinya; Seto, Osamu

    2008-01-01

    We propose an extended version of the standard model, in which neutrino oscillation, dark matter, and baryon asymmetry of the Universe can be simultaneously explained by the TeV-scale physics without assuming unnatural hierarchy among the mass scales. Tiny neutrino masses are generated at the three loop level due to the exact $Z_2$ symmetry, by which stability of the dark matter candidate is guaranteed. The extra Higgs doublet is required not only for the tiny neutrino masses but also for suc...

  12. The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: Signs of neutrino mass in current cosmological datasets

    OpenAIRE

    Beutler, Florian; Saito, Shun; Brownstein, Joel R.; Chuang, Chia-Hsun; Cuesta, Antonio J.; Percival, Will J.; Ross, Ashley J.; Ross, Nicholas P.; Schneider, Donald P.; Samushia, Lado; Sanchez, Ariel G.; Seo, Hee-Jong; Tinker, Jeremy L.; Wagner, Christian; Weaver, Benjamin A.

    2014-01-01

    We investigate the cosmological implications of the latest growth of structure measurement from the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS Data Release 11 with particular focus on the sum of the neutrino masses, $\\sum m_{\

  13. QCD's Partner needed for Mass Spectra and Parton Structure Functions

    OpenAIRE

    Kim, Y. S.

    2009-01-01

    As in the case of the hydrogen atom, bound-state wave functions are needed to generate hadronic spectra. For this purpose, in 1971, Feynman and his students wrote down a Lorentz-invariant harmonic oscillator equation. This differential equation has one set of solutions satisfying the Lorentz-covariant boundary condition. This covariant set generates Lorentz-invariant mass spectra with their degeneracies. Furthermore, the Lorentz-covariant wave functions allow us to calculate the valence parto...

  14. Spectroscopy of charmed baryons from lattice QCD

    CERN Document Server

    Padmanath, M; Mathur, Nilmani; Peardon, Michael

    2014-01-01

    We present the ground and excited state spectra of singly, doubly and triply charmed baryons by using dynamical lattice QCD. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) $\\otimes$ O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses.

  15. Spectroscopy of charmed baryons from lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Padmanath, M. [Univ. of Graz (Austria). Inst. of Physics; Edwards, Robert G. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mathur, Nilmani [Tata Institute of Fundamental Research, Bombay (India); Peardon, Michael [Trinity College, Dublin (Ireland)

    2015-01-01

    We present the ground and excited state spectra of singly, doubly and triply charmed baryons by using dynamical lattice QCD. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) x O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses.

  16. Spectroscopy of charmed baryons from lattice QCD

    International Nuclear Information System (INIS)

    We present the ground and excited state spectra of singly, doubly and triply charmed baryons by using dynamical lattice QCD. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) x O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses.

  17. Mass Spectra and Ion Collision Cross Sections of Hemoglobin

    Science.gov (United States)

    Kang, Yang; Terrier, Peran; Douglas, D. J.

    2011-02-01

    Mass spectra of commercially obtained hemoglobin (Hb) show higher levels of monomer and dimer ions, heme-deficient dimer ions, and apo-monomer ions than hemoglobin freshly prepared from blood. This has previously been attributed to oxidation of commercial Hb. Further, it has been reported that that dimer ions from commercial bovine Hb have lower collision cross sections than low charge state monomer ions. To investigate these effects further, we have recorded mass spectra of fresh human Hb, commercial human and bovine Hb, fresh human Hb oxidized with H2O2, lyophilized fresh human Hb, fresh human Hb both lyophilized and chemically oxidized, and commercial human Hb oxidized with H2O2. Masses of α-monomer ions of all hemoglobins agree with the masses expected from the sequences within 3 Da or better. Mass spectra of the β chains of commercial Hb and oxidized fresh human Hb show a peak or shoulder on the high mass side, consistent with oxidation of the protein. Both commercial proteins and oxidized fresh human Hb produce heme-deficient dimers with masses 32 Da greater than expected and higher levels of monomer and dimer ions than fresh Hb. Lyophilization or oxidation of Hb both produce higher levels of monomer and dimer ions in mass spectra. Fresh human Hb, commercial human Hb, commercial bovine Hb, and oxidized commercial human Hb all give dimer ions with cross sections greater than monomer ions. Thus, neither oxidation of Hb or the difference in sequence between human and bovine Hb make substantial differences to cross sections of ions.

  18. CHARACTERIZATION OF FULLERENE DERIVATIVES BY MALDI FRAGMENT MASS SPECTRA

    OpenAIRE

    Milman, B. L.; Piotrovsky, L. B.; Nikolaev, D. N.; Dumpis, M. A.; LITASOVA E.V.; LUGOVKINA N.V.

    2014-01-01

    MALDI and MALDI LIFT-TOF/TOF mass spectra of fullerene C60 and five its derivatives,  methano[60]fullerene carboxylic acid, its ethyl ester, diethyl methano[60]fullerene dicarboxylate, and two isomeric tetraethyl bis-methano[60]fullerene tetracarboxylates (compounds I-VI, respectively) as model analytes were recorded and discussed. The technique of MALDI LIFT used in mass spectrometry of fullerenes for the first time is proposed for their characterization, structure elucidation, and non-targe...

  19. Axial charges of hyperons and charmed baryons using $N_f=2+1+1$ twisted mass fermions

    CERN Document Server

    Alexandrou, C; Kallidonis, Ch

    2016-01-01

    The axial couplings of the low lying baryons are evaluated using a total of five ensembles of dynamical twisted mass fermion gauge configurations. The simulations are performed using the Iwasaki gauge action and two degenerate flavors of light quarks, and a strange and a charm quark fixed to approximately their physical values at two values of the coupling constant. The lattice spacings, determined using the nucleon mass, are $a=0.082$ fm and $a=0.065$ fm and the simulations cover a pion mass in the range of about 210 MeV to 430 MeV. We study the dependence of the axial couplings on the pion mass in the range of about 210 MeV to 430 MeV as well as the $SU(3)$ breaking effects as we decrease the light quark mass towards its physical value.

  20. Heavy meson mass-spectra by general relativistic methods (*)

    International Nuclear Information System (INIS)

    By applying the classical methods of general relativity to elementary particles, one can get-in a natural way-the observed confinement of their constituents, avoiding any recourse to phenomenological models such as the bag model and allowing the deduction of the heavy meson [i.e., charmonium (J/psi) and bottomonium (γ)] mass-spectra

  1. Diquark correlations in baryon spectroscopy and holographic QCD

    International Nuclear Information System (INIS)

    We improve upon recent holographic predictions for the nucleon and delta resonance spectra and show how they emerge from a straightforward extension of the ''metric soft wall'' AdS/QCD dual. The resulting mass formula depends on a single adjustable parameter, characterizing confinement-induced IR deformations of the anti-de Sitter metric, and on the fraction of ''good'' (i.e. maximally attractive) diquarks in the baryon's quark model wave function. Despite their remarkable simplicity, the predicted spectra describe the masses of all 48 observed light-quark baryon states and the underlying, linear trajectory structure with unprecedented accuracy

  2. Baryon chiral perturbation theory withWilson fermions up to O(a{sup 2}) and discretization effects of latest n{sub f} = 2 + 1 LQCD octet baryon masses

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Xiu-Lei [Beihang University, School of Physics and Nuclear Energy Engineering, Beijing (China); Beihang University, International Research Center for Nuclei and Particles in the Cosmos, Beijing (China); Geng, Li-Sheng [Beihang University, School of Physics and Nuclear Energy Engineering, Beijing (China); Beihang University, International Research Center for Nuclei and Particles in the Cosmos, Beijing (China); Technische Universitaet Muenchen, Physik Department, Garching (Germany); Meng, Jie [Beihang University, School of Physics and Nuclear Energy Engineering, Beijing (China); Beihang University, International Research Center for Nuclei and Particles in the Cosmos, Beijing (China); Peking University, State Key Laboratory of Nuclear Physics and Technology, School of Physics, Beijing (China); University of Stellenbosch, Department of Physics, Stellenbosch (South Africa)

    2014-02-15

    We construct the chiral Lagrangians relevant in studies of the ground-state octet baryon masses up to O(a{sup 2}) by taking into account discretization effects. We calculate the masses up to O(p{sup 4}) in the extended-on-mass-shell scheme. As an application, we study the latest n{sub f} = 2+1 LQCD data on the ground-state octet baryon masses from the PACS-CS, QCDSF-UKQCD, HSC, and NPLQCD Collaborations. It is shown that the discretization effects for the studied LQCD simulations are at the order of 1-2 % for lattice spacings up to 0.15 fm and the pion mass up to 500 MeV. (orig.)

  3. Mass spectra of 0+-, 1-+, and 2+- exotic glueballs

    Science.gov (United States)

    Tang, Liang; Qiao, Cong-Feng

    2016-03-01

    With appropriate interpolating currents the mass spectra of 0+-, 1-+, and 2+- oddballs are studied in the framework of QCD sum rules (QCDSR). We find there exits one stable 0+- oddball with mass of 4.57 ± 0.13GeV, and one stable 2+- oddball with mass of 6.06 ± 0.13GeV, whereas, no stable 1-+ oddball shows up. The possible production and decay modes of these glueballs with unconventional quantum numbers are analyzed, which are hopefully measurable in either BELLEII, PANDA, Super-B or LHCb experiments.

  4. aryon chiral perturbation theory with Wilson fermions up to (a2) and discretization effects of latest nf=2+1 LQCD octet baryon masses

    OpenAIRE

    Ren, Xiu-LeiSchool of Physics and Nuclear Energy Engineering, Beihang University, 100191, Beijing, China; Geng, Li-Sheng; Meng, Jie

    2014-01-01

    We construct the chiral Lagrangians relevant in studies of the ground-state octet baryon masses up to (a2) by taking into account discretization effects. We calculate the masses up to (p4) in the extended-on-mass-shell scheme. As an application, we study the latest nf=2+1 LQCD data on the ground-state octet baryon masses from the PACS-CS, QCDSF-UKQCD, HSC, and NPLQCD Collaborations. It is shown that the discretization effects for the studied LQCD simulations are at the order of 1–2 % for la...

  5. Jet mass spectra in Higgs+one jet at NNLL

    Energy Technology Data Exchange (ETDEWEB)

    Jouttenus, Teppo T.; Stewart, Iain W. [Massachusetts Institute of Technology, Cambridge, MA (United States). Center for Theoretical Physics; Tackmann, Frank J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Waalewijn, Wouter J. [California Univ., San Diego, La Jolla, CA (United States). Dept. of Physics

    2013-02-15

    The invariant mass of a jet is a benchmark variable describing the structure of jets at the LHC. We calculate the jet mass spectrum for Higgs plus one jet at the LHC at next-to-next-to-leading logarithmic (NNLL) order using a factorization formula. At this order, the cross section becomes sensitive to perturbation theory at the soft m{sup 2}{sub jet}/p{sup jet}{sub T} scale. Our calculation is exclusive and uses the 1-jettiness global event shape to implement a veto on additional jets. The dominant dependence on the jet veto is removed by normalizing the spectrum, leaving residual dependence from non-global logarithms depending on the ratio of the jet mass and jet veto variables. For our exclusive jet cross section these non-global logarithms are parametrically smaller than in the inclusive case, allowing us to obtain a complete NNLL result. Results for the dependence of the jet mass spectrum on the kinematics, jet algorithm, and jet size R are given. Using individual partonic channels we illustrate the difference between the jet mass spectra for quark and gluon jets. We also study the effect of hadronization and underlying event on the jet mass in Pythia. To highlight the similarity of inclusive and exclusive jet mass spectra, a comparison to LHC data is presented.

  6. ILC phenomenology in a TeV scale radiative seesaw model for neutrino mass, dark matter and baryon asymmetry

    OpenAIRE

    Aoki, Mayumi; Kanemura, Shinya; Seto, Osamu

    2010-01-01

    We discuss phenomenology in a new TeV scale model which would explain neutrino oscillation, dark matter, and baryon asymmetry of the Universe simultaneously by the dynamics of the extended Higgs sector and TeV-scale right-handed neutrinos. Tiny neutrino masses are generated at the three-loop level due to the exact $Z_2$ symmetry, by which the stability of the dark matter candidate is guaranteed. The model provides various discriminative predictions in Higgs phenomenology, which can be tested ...

  7. Higher-order mass defect analysis for mass spectra of complex organic mixtures.

    Science.gov (United States)

    Roach, Patrick J; Laskin, Julia; Laskin, Alexander

    2011-06-15

    Higher-order mass defect analysis is introduced as a unique formula assignment and visualization method for the analysis of complex mass spectra. This approach is an extension of the concepts of Kendrick mass transformation widely used for identification of homologous compounds differing only by a number of base units (e.g., CH(2), H(2), O, CH(2)O, etc.) in complex mixtures. We present an iterative renormalization routine for defining higher-order homologous series and multidimensional clustering of mass spectral features. This approach greatly simplifies visualization of complex mass spectra and increases the number of chemical formulas that can be confidently assigned for given mass accuracy. The potential for using higher-order mass defects for data reduction and visualization is shown. Higher-order mass defect analysis is described and demonstrated through third-order analysis of a deisotoped high-resolution mass spectrum of crude oil containing nearly 13,000 peaks. PMID:21526851

  8. Neutrino masses and mixings in the baryon triality constrained minimal supersymmetric standard model

    OpenAIRE

    Dreiner, Herbi K.; Hanussek, Marja; Kim, Jong-Soo; Kom, C. H.

    2011-01-01

    We discuss how the experimental neutrino oscillation data can be realized in the framework of the baryon triality ($B_3$) constrained supersymmetric Standard Model (cSSM). We show how to obtain phenomenologically viable solutions, which are compatible with the recent WMAP observations. We present results for the hierarchical, inverted and degenerate cases which illustrate the possible size and structure of the lepton number violating couplings. We work with a new, as yet unpublished version o...

  9. Quantitative Comparison of Tandem Mass Spectra Obtained on Various Instruments

    Science.gov (United States)

    Bazsó, Fanni Laura; Ozohanics, Oliver; Schlosser, Gitta; Ludányi, Krisztina; Vékey, Károly; Drahos, László

    2016-08-01

    The similarity between two tandem mass spectra, which were measured on different instruments, was compared quantitatively using the similarity index (SI), defined as the dot product of the square root of peak intensities in the respective spectra. This function was found to be useful for comparing energy-dependent tandem mass spectra obtained on various instruments. Spectral comparisons show the similarity index in a 2D "heat map", indicating which collision energy combinations result in similar spectra, and how good this agreement is. The results and methodology can be used in the pharma industry to design experiments and equipment well suited for good reproducibility. We suggest that to get good long-term reproducibility, it is best to adjust the collision energy to yield a spectrum very similar to a reference spectrum. It is likely to yield better results than using the same tuning file, which, for example, does not take into account that contamination of the ion source due to extended use may influence instrument tuning. The methodology may be used to characterize energy dependence on various instrument types, to optimize instrumentation, and to study the influence or correlation between various experimental parameters.

  10. CASE via MS: Ranking Structure Candidates by Mass Spectra

    OpenAIRE

    Kerber, Adalbert; Meringer, Markus; Rücker, Christoph

    2006-01-01

    Two important tasks in computer-aided structure elucidation (CASE) are the generation of candidate structures from a given molecular formula, and the ranking of structure candidates according to compatibility with an experimental spectrum. Candidate ranking with respect to electron impact mass spectra is based on virtual fragmentation of a candidate structure and comparison of the fragments’ isotope distributions against the spectrum of the unknown compound, whence a structure–spectrum compat...

  11. Automatic Validation of Phosphopeptide Identifications from Tandem Mass Spectra

    OpenAIRE

    Lu, Bingwen; Ruse, Cristian; Xu, Tao; Park, Sung Kyu; Yates, John

    2007-01-01

    We developed and compared two approaches for automated validation of phosphopeptides tandem mass spectra identified using database searching algorithms. Phosphopeptide identifications were obtained through SEQUEST searches of a protein database appended with its decoy (reversed sequences). Statistical evaluation and iterative searches were employed to create a high quality dataset of phosphopeptides. Automation of post-search validation was approached by two different strategies. By using sta...

  12. The relation between velocity dispersion and mass in simulated clusters of galaxies: dependence on the tracer and the baryonic physics

    CERN Document Server

    Munari, Emiliano; Borgani, Stefano; Murante, Giuseppe; Fabjan, Dunja

    2013-01-01

    [Abridged] We present an analysis of the relation between the masses of cluster- and group-sized halos, extracted from $\\Lambda$CDM cosmological N-body and hydrodynamic simulations, and their velocity dispersions, at different redshifts from $z=2$ to $z=0$. The main aim of this analysis is to understand how the implementation of baryonic physics in simulations affects such relation, i.e. to what extent the use of the velocity dispersion as a proxy for cluster mass determination is hampered by the imperfect knowledge of the baryonic physics. In our analysis we use several sets of simulations with different physics implemented. Velocity dispersions are determined using three different tracers, DM particles, subhalos, and galaxies. We confirm that DM particles trace a relation that is fully consistent with the theoretical expectations based on the virial theorem and with previous results presented in the literature. On the other hand, subhalos and galaxies trace steeper relations, and with larger values of the n...

  13. Cosmological constraints from the evolution of the cluster baryon mass function at z similar to 0.5

    DEFF Research Database (Denmark)

    Vikhlinin, A.; Voevodkin, A.; Mullis, C.R.;

    2003-01-01

    the large uncertainties of the M-tot-T or M-tot-L-X relations used in all previous studies. Instead, we rely on a well-founded assumption that the M-b/M-tot ratio is a universal quantity, which should result in a much smaller systematic uncertainty. Taking advantage of direct and accurate Chandra...... measurements of the gas masses for distant clusters, we find strong evolution of the baryon mass function between z > 0.4 and the present. The observed evolution defines a narrow band in the Omega(m)-Lambda plane, Omega(m) + 0.23Lambda = 0.41 +/- 0.10 at 68% confidence, which intersects with constraints from...

  14. Baryon production in e+e- annihilation

    International Nuclear Information System (INIS)

    The phenomenology of baryon production in high energy e+e-annihilation is described. Much can be understood in terms of mass effects. Comparisons with the rates for different flavours and spins, with momentum and transverse momentum spectra and with particle correlations are used to confront models. Diquark models give good descriptions, except for the on/off Υ(1s) rates. Areas for experimental and theoretical development are indicated. (author)

  15. Mass Spectra of $0^{+-}$, $1^{-+}$, and $2^{+-}$ Exotic Glueballs

    CERN Document Server

    Qiao, Cong-Feng

    2015-01-01

    With appropriate interpolating currents the mass spectra of $0^{+-}$, $1^{-+}$, and $2^{+-}$ oddballs are studied in the framework of QCD sum rules (QCDSR). We find there exits a stable $0^{+-}$ oddball with mass of $4.57 \\pm 0.13 \\, \\text{GeV}$, and three stable $2^{+-}$ oddballs with masses of $2.77 \\pm 0.11$, $4.41 \\pm 0.13$, and $4.99 \\pm 0.14 \\, \\text{GeV}$, whereas, no stable $1^{-+}$ oddball shows up. The possible production and decay modes of these glueballs with unconventional quantum numbers are analyzed, which are hopefully measurable in either BESIII, BELLEII, PANDA, Super-B or LHCb experiments.

  16. Mass spectra of alkaloids from cissampelos pareira L Mass spectra of alkaloids from cissampelos pareira L.

    Directory of Open Access Journals (Sweden)

    Aguirre Gálviz Luis Enrique

    1988-06-01

    -bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:EN-US;} .MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;} @page WordSection1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.WordSection1 {page:WordSection1;} -->

    The mass spectra of the tertiary bis-benzyl-isoquinoline alkaloids, warifteine and methyl-warifteine, extracted from the ethnobotanically important species, Cissampelos pareira L.. are discussed. Infonnation about the reltive positions of two hydroxyl and two methoxyl groups in warifteine and the presence of a p-xylyl moiety in both compounds in provided.

    Se presenta una discusión de los espectros de masas de warifteina y metilwarifteina, dos alcaloides

  17. QCD's Partner Needed for Mass Spectra and Parton Structure Functions

    International Nuclear Information System (INIS)

    as in the case of the hydrogen atom, bound-state wave functions are needed to generate hadronic spectra. For this purpose, in 1971, Feynman and his students wrote down a Lorentz-invariant harmonic oscillator equation. This differential equation has one set of solutions satisfying the Lorentz-covariant boundary condition. This covariant set generates Lorentz-invariant mass spectra with their degeneracies. Furthermore, the Lorentz-covariant wave functions allow us to calculate the valence parton distribution by Lorentz-boosting the quark-model wave function from the hadronic rest frame. However, this boosted wave function does not give an accurate parton distribution. The wave function needs QCD corrections to make a contact with the real world. Likewise, QCD needs the wave function as a starting point for calculating the parton structure function. (author)

  18. Evidence for a narrow |S|=1 baryon state at a mass of 1528 MeV in quasi-real photoproduction

    CERN Document Server

    Airapetian, A; Akopov, Z; Amarian, M; Ammosov, V V; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Balin, D; Baturin, V; Beckmann, M; Belostotskii, S; Bernreuther, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Borysenko, A; Bouwhuis, M; Brack, J; Brüll, A; Bryzgalov, V V; Capitani, G P; Chen, T; Chen, X; Chiang, H C; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; Deconinck, W; De Leo, R; De Nardo, L; De Sanctis, E; Devitsin, E G; Di Nezza, P; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G M; Ellinghaus, F; Elschenbroich, U; Ely, J; Fabbri, R; Fantoni, A; Feshchenko, A; Felawka, L; Fox, B; Frullani, S; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Garutti, E; Gaskell, D; Gavrilov, G E; Karibian, V; Graw, G; Grebenyuk, O; Greeniaus, L G; Gregor, I M; Hafidi, K; Hartig, M; Hasch, D; Heesbeen, D; Henoch, M; Hertenberger, R; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Kinney, E; Kiselev, A; Kopytin, M; Korotkov, V; Kozlov, V; Krauss, B; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Laziev, A; Lenisa, P; Liebing, P; Linden-Levy, L A; Lipka, K; Lorenzon, W; Lü, H; Lü, J; Lu, S; Lü, X; Ma, B Q; Maiheu, B; Makins, N C R; Mao, Y; Marianski, B; Marukyan, H O; Masoli, F; Mexner, V; Meyners, N; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Nass, A; Negodaev, M A; Nowak, Wolf-Dieter; Oganessyan, K; Ohsuga, H; Pickert, N; Potashov, S Yu; Potterveld, D H; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubacek, L; Rubin, J; Ryckbosch, D; Salomatin, Yu I; Sanjiev, I; Savin, I; Schäfer, A; Schill, C; Schnell, G; Schüler, K P; Seele, J; Seidl, R; Seitz, B; Shanidze, R G; Shearer, C; Shibata, T A; Shutov, V B; Simani, M C; Sinram, K; Stancari, M D; Statera, M; Steffens, E; Steijger, J J M; Stenzel, H; Stewart, J; Stinzing, F; Stösslein, U; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Tkabladze, A V; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Vetterli, Martin C; Vikhrov, V; Vincter, M G; Vogel, C; Vogt, M; Volmer, J; Weiskopf, C; Wendland, J; Wilbert, J; Ybeles-Smit, G V; Ye, Y; Ye, Z; Yen, S; Yu, W; Zihlmann, B; Zohrabyan, H G; Zupranski, P

    2003-01-01

    Evidence for a narrow baryon state is found in quasi-real photoproduction on a deuterium target through the decay channel p K^0_S --> p pi^+ pi^-. A peak is observed in the p K^0_S invariant mass spectrum at 1528 +/- 2.6 (stat) +/-2.1 (syst) MeV. Depending on the background model,the naive statistical significance of the peak is 4--6 standard deviations and its width may be somewhat larger than the experimental resolution of sigma=4.3 -- 6.2 MeV. This state may be interpreted as the predicted S=+1 exotic Theta^{+}(uuddbar(s)) pentaquark baryon. No signal for an hypothetical Theta^{++} baryon was observed in the pK^+ invariant mass distribution. The absence of such a signal indicates that an isotensor Theta is excluded and an isovector Theta is unlikely.

  19. Mass and lifetime measurements of bottom and charm baryons in $p\\bar p$ collisions at $\\sqrt{s}= 1.96 TeV

    CERN Document Server

    Aaltonen, Timo Antero; Amidei, Dante E; Anastassov, Anton Iankov; Annovi, Alberto; Antos, Jaroslav; Apollinari, Giorgio; Appel, Jeffrey A; Arisawa, Tetsuo; Artikov, Akram Muzafarovich; Asaadi, Jonathan A; Ashmanskas, William Joseph; Auerbach, Benjamin; Aurisano, Adam J; Azfar, Farrukh A; Badgett, William Farris; Bae, Taegil; Barbaro-Galtieri, Angela; Barnes, Virgil E; Barnett, Bruce Arnold; Barria, Patrizia; Bartos, Pavol; Bauce, Matteo; Bedeschi, Franco; Behari, Satyajit; Bellettini, Giorgio; Bellinger, James Nugent; Benjamin, Douglas P; Beretvas, Andrew F; Bhatti, Anwar Ahmad; Bland, Karen Renee; Blumenfeld, Barry J; Bocci, Andrea; Bodek, Arie; Bortoletto, Daniela; Boudreau, Joseph Francis; Boveia, Antonio; Brigliadori, Luca; Bromberg, Carl Michael; Brucken, Erik; Budagov, Ioulian A; Budd, Howard Scott; Burkett, Kevin Alan; Busetto, Giovanni; Bussey, Peter John; Butti, Pierfrancesco; Buzatu, Adrian; Calamba, Aristotle; Camarda, Stefano; Campanelli, Mario; Canelli, Florencia; Carls, Benjamin; Carlsmith, Duncan L; Carosi, Roberto; Carrillo Moreno, Salvador; Casal Larana, Bruno; Casarsa, Massimo; Castro, Andrea; Catastini, Pierluigi; Cauz, Diego; Cavaliere, Viviana; Cavalli-Sforza, Matteo; Cerri, Alessandro; Cerrito, Lucio; Chen, Yen-Chu; Chertok, Maxwell Benjamin; Chiarelli, Giorgio; Chlachidze, Gouram; Cho, Kihyeon; Chokheli, Davit; Clark, Allan Geoffrey; Clarke, Christopher Joseph; Convery, Mary Elizabeth; Conway, John Stephen; Corbo, Matteo; Cordelli, Marco; Cox, Charles Alexander; Cox, David Jeremy; Cremonesi, Matteo; Cruz Alonso, Daniel; Cuevas Maestro, Javier; Culbertson, Raymond Lloyd; D'Ascenzo, Nicola; Datta, Mousumi; de Barbaro, Pawel; Demortier, Luc M; Deninno, Maria Maddalena; D'Errico, Maria; Devoto, Francesco; Di Canto, Angelo; Di Ruzza, Benedetto; Dittmann, Jay Richard; Donati, Simone; D'Onofrio, Monica; Dorigo, Mirco; Driutti, Anna; Ebina, Koji; Edgar, Ryan Christopher; Elagin, Andrey L; Erbacher, Robin D; Errede, Steven Michael; Esham, Benjamin; Farrington, Sinead Marie; Fernández Ramos, Juan Pablo; Field, Richard D; Flanagan, Gene U; Forrest, Robert David; Franklin, Melissa EB; Freeman, John Christian; Frisch, Henry J; Funakoshi, Yujiro; Galloni, Camilla; Garfinkel, Arthur F; Garosi, Paola; Gerberich, Heather Kay; Gerchtein, Elena A; Giagu, Stefano; Giakoumopoulou, Viktoria Athina; Gibson, Karen Ruth; Ginsburg, Camille Marie; Giokaris, Nikos D; Giromini, Paolo; Giurgiu, Gavril A; Glagolev, Vladimir; Glenzinski, Douglas Andrew; Gold, Michael S; Goldin, Daniel; Golossanov, Alexander; Gomez, Gervasio; Gomez-Ceballos, Guillelmo; Goncharov, Maxim T; González López, Oscar; Gorelov, Igor V; Goshaw, Alfred T; Goulianos, Konstantin A; Gramellini, Elena; Grinstein, Sebastian; Grosso-Pilcher, Carla; Group, Robert Craig; Guimaraes da Costa, Joao; Hahn, Stephen R; Han, Ji-Yeon; Happacher, Fabio; Hara, Kazuhiko; Hare, Matthew Frederick; Harr, Robert Francis; Harrington-Taber, Timothy; Hatakeyama, Kenichi; Hays, Christopher Paul; Heinrich, Joel G; Herndon, Matthew Fairbanks; Hocker, James Andrew; Hong, Ziqing; Hopkins, Walter Howard; Hou, Suen Ray; Hughes, Richard Edward; Husemann, Ulrich; Hussein, Mohammad; Huston, Joey Walter; Introzzi, Gianluca; Iori, Maurizio; Ivanov, Andrew Gennadievich; James, Eric B; Jang, Dongwook; Jayatilaka, Bodhitha Anjalike; Jeon, Eun-Ju; Jindariani, Sergo Robert; Jones, Matthew T; Joo, Kyung Kwang; Jun, Soon Yung; Junk, Thomas R; Kambeitz, Manuel; Kamon, Teruki; Karchin, Paul Edmund; Kasmi, Azeddine; Kato, Yukihiro; Ketchum, Wesley Robert; Keung, Justin Kien; Kilminster, Benjamin John; Kim, DongHee; Kim, Hyunsoo; Kim, Jieun; Kim, Min Jeong; Kim, Shin-Hong; Kim, Soo Bong; Kim, Young-Jin; Kim, Young-Kee; Kimura, Naoki; Kirby, Michael H; Knoepfel, Kyle James; Kondo, Kunitaka; Kong, Dae Jung; Konigsberg, Jacobo; Kotwal, Ashutosh Vijay; Kreps, Michal; Kroll, IJoseph; Kruse, Mark Charles; Kuhr, Thomas; Kurata, Masakazu; Laasanen, Alvin Toivo; Lammel, Stephan; Lancaster, Mark; Lannon, Kevin Patrick; Latino, Giuseppe; Lee, Hyun Su; Lee, Jaison; Leo, Sabato; Leone, Sandra; Lewis, Jonathan D; Limosani, Antonio; Lipeles, Elliot David; Lister, Alison; Liu, Hao; Liu, Qiuguang; Liu, Tiehui Ted; Lockwitz, Sarah E; Loginov, Andrey Borisovich; Lucchesi, Donatella; Lucà, Alessandra; Lueck, Jan; Lujan, Paul Joseph; Lukens, Patrick Thomas; Lungu, Gheorghe; Lys, Jeremy E; Lysak, Roman; Madrak, Robyn Leigh; Maestro, Paolo; Malik, Sarah Alam; Manca, Giulia; Manousakis-Katsikakis, Arkadios; Marchese, Luigi Marchese; Margaroli, Fabrizio

    2014-01-01

    We report on mass and lifetime measurements of several ground state charmed and bottom baryons, using a data sample corresponding to 9.6 $\\textrm{fb}^{-1}$ from $p\\bar p$ collisions at $\\sqrt{s}=1.96$ TeV, and recorded with the Collider Detector at Fermilab. Baryon candidates are reconstructed from data collected with an online event selection designed for the collection of long-lifetime heavy-flavor decay products and a second event selection designed to collect $J/\\psi \\rightarrow \\mu^+ \\, \\mu^-$ candidates. First evidence for the process $\\Omega_b^- \\rightarrow \\Omega_c^0 \\, \\pi^-$ is presented with a significance of $3.3\\sigma$. We measure the following baryon masses: \\begin{eqnarray} M(\\Xi_c^{0}) = 2470.85\\pm0.24(stat)\\pm0.55(syst) \\, MeV/c^2, \

  20. decays to baryons

    Indian Academy of Sciences (India)

    Torsten Leddig

    2012-11-01

    From inclusive measurements, it is known that about 7% of all mesons decay into final states with baryons. In these decays, some striking features become visible compared to mesonic decays. The largest branching fractions come with quite moderate multiplicities of 3–4 hadrons. We note that two-body decays to baryons are suppressed relative to three- and four-body decays. In most of these analyses, the invariant baryon–antibaryon mass shows an enhancement near the threshold. We propose a phenomenological interpretation of this quite common feature of hadronization to baryons.

  1. Mass spectra of heavy quarkonia using Cornell plus harmonic potential

    International Nuclear Information System (INIS)

    The solution of the non-relativistic radial Schrödinger equation (SE) with spherical symmetrical potentials plays an important role in atomic and hadronic spectroscopy. The non-relativistic quark model is commonly employed for knowing the behavior of heavy hadron. The non-relativistic approximation is good for obtaining the mass spectra of heavy mesons consisting of heavy quark and antiquark (Υ(bb-bar), (ψcc-bar)). This approximation provides a good description of static properties of heavy mesons such as mass spectra, radios etc. while for dynamical properties such as decay, the relativistic corrections are considered. The interaction potential for these system is of Cornell type i.e. Coulomb plus linear terms. The Coulomb term is to be liable for the interaction at small distances and linear term leads to the confinement. This type of interaction potential is accompanied by lattice quantum chromodynamics calculations. The quark-antiquark interaction has also been studied using Coulomb plus power potential

  2. Interpretation of tandem mass spectra obtained from cyclic nonribosomal peptides.

    Science.gov (United States)

    Liu, Wei-Ting; Ng, Julio; Meluzzi, Dario; Bandeira, Nuno; Gutierrez, Marcelino; Simmons, Thomas L; Schultz, Andrew W; Linington, Roger G; Moore, Bradley S; Gerwick, William H; Pevzner, Pavel A; Dorrestein, Pieter C

    2009-06-01

    Natural and non-natural cyclic peptides are a crucial component in drug discovery programs because of their considerable pharmaceutical properties. Cyclosporin, microcystins, and nodularins are all notable pharmacologically important cyclic peptides. Because these biologically active peptides are often biosynthesized nonribosomally, they often contain nonstandard amino acids, thus increasing the complexity of the resulting tandem mass spectrometry data. In addition, because of the cyclic nature, the fragmentation patterns of many of these peptides showed much higher complexity when compared to related counterparts. Therefore, at the present time it is still difficult to annotate cyclic peptides MS/MS spectra. In this current work, an annotation program was developed for the annotation and characterization of tandem mass spectra obtained from cyclic peptides. This program, which we call MS-CPA is available as a web tool (http://lol.ucsd.edu/ms-cpa_v1/Input.py). Using this program, we have successfully annotated the sequence of representative cyclic peptides, such as seglitide, tyrothricin, desmethoxymajusculamide C, dudawalamide A, and cyclomarins, in a rapid manner and also were able to provide the first-pass structure evidence of a newly discovered natural product based on predicted sequence. This compound is not available in sufficient quantities for structural elucidation by other means such as NMR. In addition to the development of this cyclic annotation program, it was observed that some cyclic peptides fragmented in unexpected ways resulting in the scrambling of sequences. In summary, MS-CPA not only provides a platform for rapid confirmation and annotation of tandem mass spectrometry data obtained with cyclic peptides but also enables quantitative analysis of the ion intensities. This program facilitates cyclic peptide analysis, sequencing, and also acts as a useful tool to investigate the uncommon fragmentation phenomena of cyclic peptides and aids the

  3. Mass spectra in softly broken ${\\cal N}=2$ SQCD

    CERN Document Server

    Chernyak, Victor L

    2016-01-01

    Considered is ${\\cal N}=2\\,\\, SU(N_c)$ or $U(N_c)$ SQCD with $N_c+1mass term $m{\\rm Tr} ({\\bar Q} Q)$ in the superpotential. It is softly broken down to ${\\cal N}=1$ by the mass term $\\mu_{\\rm x}{\\rm Tr} (X^2)$ of colored adjoint scalar partners of gluons, $\\mu_{\\rm x}\\ll\\Lambda_2$ ( $\\Lambda_2$ is the scale factor of the $SU(N_c)$ gauge coupling). There is a large number of different types of vacua in this theory with both unbroken and spontaneously broken global flavor symmetry $U(N_F)\\rightarrow U({\\rm n}_1)\\times U({\\rm n}_2)$. We consider in this paper the large subset of these vacua with the unbroken nontrivial $Z_{2N_c-N_F\\geq 2}$ discrete symmetry, at different hierarchies between the Lagrangian parameters $m\\gtrless\\Lambda_2,\\, \\mu_{\\rm x}\\gtrless m$. The forms of low energy Lagrangians, quantum numbers of light particles and mass spectra are described for all these vacua. Our results differ from corresponding results in recent papers arXiv:1304.0822; 1403.60...

  4. Interpretation of tandem mass spectra of posttranslationally modified peptides

    DEFF Research Database (Denmark)

    Bunkenborg, J.; Matthiesen, R.

    2013-01-01

    spectra and protein database search engines have been developed to match the experimental data to peptide candidates. In most studies there is a schism between discarding perfectly valid data and including nonsensical peptide identifications-this is currently a major bottleneck in data-analysis and it...... calls for an understanding of tandem mass spectrometry data. Manual evaluation of the data and perhaps experimental cross-checking of the MS data can save many months of experimental work trying to do biological follow-ups based on erroneous identifications. Especially for posttranslationally modified...... peptides there is a need for manual validation of the data because search algorithms seldom have been optimized for the identification of modified peptides and because there are many pitfalls for the unwary. This chapter describes some of the issues that should be considered when interpreting and...

  5. Spectroscopy of doubly-charmed baryons from lattice QCD

    CERN Document Server

    Padmanath, M; Mathur, Nilmani; Peardon, Michael

    2015-01-01

    We present the ground and excited state spectra of doubly charmed baryons from lattice QCD with dynamical quark fields. Calculations are performed on anisotropic lattices of size 16^3 X 128, with inverse spacing in temporal direction 1/a_t = 5.67(4) GeV and with a pion mass of about 390 MeV. A large set of baryonic operators that respect the symmetries of the lattice yet which retain a memory of their continuum analogues are used. These operators transform as irreducible representations of SU(3) symmetry for flavor, SU(4) symmetry for Dirac spins of quarks and O(3) for spatial symmetry. The distillation method is utilized to generate baryon correlation functions which are analysed using the variational fitting method to extract excited states. The lattice spectra obtained have baryonic states with well-defined total spins up to 7/2 and the pattern of low lying states does not support the diquark picture for doubly charmed baryons. On the contrary the calculated spectra are remarkably similar to the expectatio...

  6. Spectroscopy of doubly charmed baryons from lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Padmanath, M. [Univ. of Graz, Graz (Austria); Edwards, Robert G. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mathur, Nilmani [Tata Inst. of Fundamental Research, Mumbai (India); Peardon, Michael [Trinity College, Dublin (Ireland)

    2015-05-06

    This study presents the ground and excited state spectra of doubly charmed baryons from lattice QCD with dynamical quark fields. Calculations are performed on anisotropic lattices of size 16³ × 128, with inverse spacing in temporal direction at⁻¹=5.67(4) GeV and with a pion mass of about 390 MeV. A large set of baryonic operators that respect the symmetries of the lattice yet which retain a memory of their continuum analogues are used. These operators transform as irreducible representations of SU(3)F symmetry for flavor, SU(4) symmetry for Dirac spins of quarks and O(3) for spatial symmetry. The distillation method is utilized to generate baryon correlation functions which are analyzed using the variational fitting method to extract excited states. The lattice spectra obtained have baryonic states with well-defined total spins up to 7/2 and the pattern of low-lying states does not support the diquark picture for doubly charmed baryons. On the contrary the calculated spectra are remarkably similar to the expectations from models with an SU(6)×O(3) symmetry. Various spin-dependent energy splittings between the extracted states are also evaluated.

  7. Why baryons are Yang-Mills magnetic monopoles, validated by nuclear binding energies and proton and neutron masses

    Science.gov (United States)

    Yablon, Jay R.

    2013-10-01

    Evidence is summarized from four recent papers that baryons including protons and neutrons are magnetic monopoles of non-commuting Yang-Mills gauge theories: 1) Protons and neutrons are ``resonant cavities'' with binding energies determined strictly by the masses of the quarks they contain. This is proven true at parts-per million accuracy for each of the 2H, 3H,3He, 4He binding energies and the neutron minus proton mass difference. 2) Respectively, each free proton and neutron contains 7.64 MeV and 9.81 MeV of mass/energy used to confine its quarks. When these nucleons bind, some, never all, of this energy is released and the mass deficit goes into binding. The balance continues to confine quarks. 56Fe releases 99.8429% of this energy for binding, more than any other nuclide. 3) Once we consider the Fermi vev one also finds an entirely theoretical explanation of proton and neutron masses, which also connects within experimental errors to the CKM quark mixing angles. 4) A related GUT explains fermion generation replication based on generator loss during symmetry breaking, and answers Rabi's question ``who ordered this?'' 5) Nuclear physics is governed by combining Maxwell's two classical equations into one equation using non-commuting gauge fields in view of Dirac theory and Fermi-Dirac-Pauli Exclusion. 6) Atoms themselves are core magnetic charges (nucleons) paired with orbital electric charges (electrons and elusive neutrinos), with the periodic table itself revealing an electric/magnetic symmetry of Maxwell's equations often pondered but heretofore unrecognized for a century and a half.

  8. Occam's Razor in Lepton Mass Matrices - The Sign of Universe's Baryon Asymmetry -

    CERN Document Server

    Kaneta, Yuya; Tanimoto, Morimitsu; Yanagida, Tsutomu T

    2016-01-01

    We discuss the neutrino mass matrix based on the Occam's Razor approach in the framework of the seesaw mechanism. We impose four zeros in the Dirac neutrino mass matrix, which give the minimum number of parameters needed for the observed neutrino masses and lepton mixing angles, while the charged lepton mass matrix and the right-handed Majorana neutrino mass matrix are taken to be real diagonal ones. The low-energy neutrino mass matrix has only seven physical parameters. We show successful predictions for the mixing angle $\\theta_{13}$ and the CP violating phase $\\delta_{CP}$ with the normal mass hierarchy of neutrinos by using the experimental data on the neutrino mass differences, the mixing angles $\\theta_{12}$ and $\\theta_{23}$. The most favored region of $\\sin\\theta_{13}$ is around $0.13\\sim 0.15$, which is completely consistent with the observed value. The CP violating phase $\\delta_{CP}$ is favored to be close to $\\pm \\pi/2$. We also discuss the Majorana phases as well as the effective neutrino mass fo...

  9. The Local Ly-alpha Forest IV: STIS G140M Spectra and Results on the Distribution and Baryon Content of HI Absorbers

    CERN Document Server

    Penton, S V; Shull, J M; Penton, Steven V.; Stocke, John T.

    2004-01-01

    We present HST STIS/G140M spectra of 15 extragalactic targets, which we combine with GHRS/G160M data to examine the statistical properties of the low-z Ly-alpha forest. We evaluate the physical properties of these Ly-alpha absorbers and compare them to their high-z counterparts. We determine that the warm, photoionized IGM contains 29+/-4% of the total baryon inventory at z = 0. We derive the distribution in column density, N_HI^(1.65+/-0.07) for 12.5 14.5. The slowing of the number density evolution of high-W Ly-alpha clouds is not as great as previously measured, and the break to slower evolution may occur later than previously suggested (z~1.0 rather than 1.6). We find a 7.2sigma excess in the two-point correlation function (TPCF) of Ly-alpha absorbers for velocity separations less than 260 km/s, which is exclusively due to the higher column density clouds. From our previous result that higher column density Ly-alpha clouds cluster more strongly with galaxies, this TPCF suggests a physical difference betw...

  10. Study of Baryon and Antibaryon Spectra in Lead Lead Interactions at 160 GeV/c per Nucleon

    CERN Multimedia

    2002-01-01

    % WA97 \\\\ \\\\ Hyperons are expected to be a useful probe for the dynamics of hadronic matter under extreme conditions. In particular the onset of a Quark-Gluon Plasma phase in a heavy ion collision is expected to enhance the hyperon yield with respect to normal hadronic interactions. \\\\ \\\\WA97 aims to measure the spectra of strange particles and in particular of hyperons and antihyperons produced in ultrarelativistic lead-lead interactions and to compare them with those from proton initiated reactions. The experiment covers central rapidity down to transverse momenta of a few hundred MeV/c. The experimental setup consists of: an array of multiplicity counters, a silicon based decay detector made of pixels, located in the CERN-OMEGA Spectrometer, an array of pad cathode MWPCs used as lever arm detectors and a zero degree hadron calorimeter. \\\\ \\\\

  11. The MOSDEF Survey: Dynamical and Baryonic Masses and Kinematic Structures of Star-forming Galaxies at 1.4 ≤ z ≤ 2.6

    Science.gov (United States)

    Price, Sedona H.; Kriek, Mariska; Shapley, Alice E.; Reddy, Naveen A.; Freeman, William R.; Coil, Alison L.; de Groot, Laura; Shivaei, Irene; Siana, Brian; Azadi, Mojegan; Barro, Guillermo; Mobasher, Bahram; Sanders, Ryan L.; Zick, Tom

    2016-03-01

    We present {{H}}α gas kinematics for 178 star-forming galaxies at z˜ 2 from the MOSFIRE Deep Evolution Field survey. We have developed models to interpret the kinematic measurements from fixed-angle multi-object spectroscopy, using structural parameters derived from Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey Hubble Space Telescope/F160W imaging. For 35 galaxies, we measure resolved rotation with a median of {(V/{σ }V,0)}{RE} = 2.1. We derive dynamical masses from the kinematics and sizes and compare them to baryonic masses, with gas masses estimated from dust-corrected {{H}}α star formation rates (SFRs) and the Kennicutt-Schmidt relation. When assuming that galaxies with and without observed rotation have the same median {(V/{σ }V,0)}{RE}, we find good agreement between the dynamical and baryonic masses, with a scatter of {σ }{rms} = 0.34 {dex} and a median offset of {{Δ }}{{log}}10 M = 0.04 {dex}. This comparison implies a low dark matter fraction (8% within an effective radius) for a Chabrier initial mass function (IMF), and disfavors a Salpeter IMF. Moreover, the requirement that {M}{dyn}/{M}{baryon} should be independent of inclination yields a median value of {(V/{σ }V,0)}{RE} = 2.1 for galaxies without observed rotation. If, instead, we treat the galaxies without detected rotation as early-type galaxies, the masses are also in reasonable agreement ({{Δ }}{{log}}10 M = -0.07 {dex}, {σ }{rms} = 0.37 {dex}). The inclusion of gas masses is critical in this comparison; if gas masses are excluded, there is an increasing trend of {M}{dyn}/{M}* with higher specific SFR (SSFR). Furthermore, we find indications that V/σ decreases with increasing {{H}}α SSFR for our full sample, which may reflect disk settling. We also study the Tully-Fisher relation and find that at fixed stellar mass {S}0.5 = {(0.5{V}2.22+{σ }V,02)}1/2 was higher at earlier times. At fixed baryonic mass, we observe the opposite trend. Finally, the baryonic and

  12. Mass Spectra of Some Diterpenoids with the Novel Carbon Skeletons Verrucosane, Neoverrucosane and Homoverrucosane

    OpenAIRE

    Eguchi, Shizuko; Matsuo, Akihiko; Nakayama, Mitsuru; Takaoka, Daisuke; Hayashi, Shûichi; 松尾, 昭彦; マツオ, アキヒコ

    1982-01-01

    The mass spectra of fifteen diterpenoids belonging to the new carbon skeletons of verrucosane, neoverrucosane and homoverrucosane are examined. From their spectra the relationship between fragmentation patterns and substituted modes of these diterpenoids is discussed.

  13. Baryonic dark matter

    International Nuclear Information System (INIS)

    Dark matter, first definitely found in the large clusters of galaxies, is now known to be dominant mass in the outer parts of galaxies. All the mass definitely deduced could be made up of baryons, and this would fit well with the requirements of nucleosynthesis in a big bang of small ΩB. However, if inflation is the explanation of the expansion and large scale homogeneity of the universe and of baryon synthesis, and if the universe did not have an infinite extent at the big bang, then Ω should be minutely greater than unity. It is commonly hypothesized that most mass is composed of some unknown, non-baryonic form. This book first discusses the known forms, comets, planets, brown dwarfs, stars, gas, galaxies and Lyman α clouds in which baryons are known to exist. Limits on the amount of dark matter in baryonic form are discussed in the context of the big bang. Inhomogeneities of the right type alleviate the difficulties associated with ΩB = 1 cosmological nucleosynthesis

  14. Enhancement of strange and multi-strange baryons in central Pb-Pb interactions at 158 GeV/c per nucleon

    CERN Document Server

    Evans, D; Bakke, H; Beusch, Werner; Bloodworth, Ian J; Caliandro, R; Carrer, N; Di Bari, D; Di Liberto, S; Elia, D; Fanebust, K; Fini, R A; Ftácnik, J; Ghidini, B; Grella, G; Helstrup, H; Holme, A K; Huss, D; Jacholkowski, A; Jones, G T; Kinson, J B; Knudson, K P; Králik, I; Lenti, V; Lietava, R; Loconsole, R A; Løvhøiden, G; Manzari, V; Mazzoni, M A; Meddi, F; Michalon, A; Michalon-Mentzer, M E; Morando, M; Norman, P I; Pastircák, B; Quercigh, Emanuele; Romano, G; Safarík, K; Sándor, L; Segato, G F; Staroba, P; Thompson, M; Thorsteinsen, T F; Torrieri, G D; Tveter, T S; Urbán, J; Villalobos Baillie, O; Virgili, T; Votruba, M F; Závada, P

    2000-01-01

    Strange and multi-strange baryon production is expected to be enhanced in heavy ion interactions if a phase transition from hadronic matter to a quark-gluon plasma takes place. The production yields and transverse mass spectra of strange and multi-strange baryons and anti-baryons are presented for lead-lead interactions at 158 GeV/c per nucleon. Yields and transverse mass spectra from proton-lead and proton-beryllium interactions, where no phase transition is expected, are also presented and compared to those from lead-lead interactions. (5 refs).

  15. Enhancement of strange and multi-strange baryons in central Pb-Pb interactions at 158 GeV/c per nucleon

    International Nuclear Information System (INIS)

    Strange and multi-strange baryon production is expected to be enhanced in heavy ion interactions if a phase transition from hadronic matter to a Quark-Gluon Plasma takes place. The production yields and transverse mass spectra of strange and multi-strange baryons and anti-baryons are presented for lead-lead interactions at 158 GeV/c per nucleon. Yields and transverse mass spectra from proton-lead and proton-beryllium interactions, where no phase transition is expected, are also presented and compared to those from lead-lead interactions

  16. Interpretation of collision-induced fragmentation tandem mass spectra of posttranslationally modified peptides

    DEFF Research Database (Denmark)

    Bunkenborg, Jakob; Matthiesen, Rune

    2007-01-01

    Tandem collision-induced dissociation (CID) mass spectrometry (MS) provides a sensitive means of analyzing the amino acid sequence of peptides. Modern MS instrumentation is capable of rapidly generating many thousands of tandem mass spectra, and protein database search engines have been developed...... validating low-energy CID tandem mass spectra and gives some useful tables to aid this process....

  17. Negative-parity baryon masses using an Ο(α)-improved fermion action

    International Nuclear Information System (INIS)

    We present a calculation of the mass of the lowest-lying negative-parity J = 1/2- state in quenched QCD. Results are obtained using a non-perturbatively O(a)-improved clover fermion action, and a splitting is found between the masses of the nucleon, and its parity partner. The calculation is performed on two lattice volumes and at three lattice spacings, enabling a study of both finite-volume and finite lattice-spacing uncertainties. A comparison is made with results obtained using the unimproved Wilson fermion action. (orig.)

  18. Baryonic Popcorn

    OpenAIRE

    Kaplunovsky, Vadim; Melnikov, Dmitry; Sonnenschein, Jacob

    2012-01-01

    In the large N limit cold dense nuclear matter must be in a lattice phase. This applies also to holographic models of hadron physics. In a class of such models, like the generalized Sakai-Sugimoto model, baryons take the form of instantons of the effective flavor gauge theory that resides on probe flavor branes. In this paper we study the phase structure of baryonic crystals by analyzing discrete periodic configurations of such instantons. We find that instanton configurations exhibit a serie...

  19. Forged in FIRE: cusps, cores, and baryons in low-mass dwarf galaxies

    CERN Document Server

    Oñorbe, Jose; Bullock, James S; Hopkins, Philip F; Kerěs, Dušan; Faucher-Giguère, Claude-André; Quataert, Eliot; Murray, Norman

    2015-01-01

    We present ultra-high resolution cosmological hydrodynamic simulations of $M_*\\simeq10^{4-6}M_{\\odot}$ dwarf galaxies that form within $M_{v}=10^{9.5-10}M_{\\odot}$ dark matter halos. Our simulations rely on the FIRE implementation of star formation feedback and were run with high enough force and mass resolution to directly resolve stellar and dark matter structure on the ~200 pc scales of interest for classical and ultra-faint dwarfs in the Local Group. The resultant galaxies sit on the $M_*$ vs. $M_{v}$ relation required to match the Local Group stellar mass function. They have bursty star formation histories and also form with half-light radii and metallicities that broadly match those observed for local dwarfs at the same stellar mass. For the first time we demonstrate that it is possible to create a large (~1 kpc) dark matter core in a cosmological simulation of an $M_*\\simeq10^6M_{\\odot}$ dwarf galaxy that resides within an $M_{v}=10^{10}M_{\\odot}$ halo -- precisely the scale of interest for resolving t...

  20. The COS-Halos survey: physical conditions and baryonic mass in the low-redshift circumgalactic medium

    Energy Technology Data Exchange (ETDEWEB)

    Werk, Jessica K.; Prochaska, J. Xavier; Tejos, Nicolas [UCO/Lick Observatory, University of California, Santa Cruz, CA (United States); Tumlinson, Jason; Peeples, Molly S.; Fox, Andrew J.; Thom, Christopher; Bordoloi, Rongmon [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD (United States); Tripp, Todd M.; Katz, Neal [Department of Astronomy, University of Massachusetts, Amherst, MA (United States); Lehner, Nicolas [Department of Physics and Astronomy, University of Notre Dame, South Bend, IN (United States); O' Meara, John M. [Department of Chemistry and Physics, Saint Michael' s College, Colchester, VT (United States); Ford, Amanda Brady [Astronomy Department, University of Arizona, Tucson, AZ 85721 (United States); Oppenheimer, Benjamin D. [Leiden Observatory, Leiden University, NL-2300 RA Leiden (Netherlands); Davé, Romeel [University of the Western Cape, Bellville, Cape Town 7535 (South Africa); Weinberg, David H., E-mail: jwerk@ucolick.org [Department of Astronomy, The Ohio State University, Columbus, OH (United States)

    2014-09-01

    We analyze the physical conditions of the cool, photoionized (T ∼10{sup 4} K) circumgalactic medium (CGM) using the COS-Halos suite of gas column density measurements for 44 gaseous halos within 160 kpc of L ∼ L* galaxies at z ∼ 0.2. These data are well described by simple photoionization models, with the gas highly ionized (n {sub H} {sub II}/n {sub H} ≳ 99%) by the extragalactic ultraviolet background. Scaling by estimates for the virial radius, R {sub vir}, we show that the ionization state (tracked by the dimensionless ionization parameter, U) increases with distance from the host galaxy. The ionization parameters imply a decreasing volume density profile n {sub H} = (10{sup –4.2±0.25})(R/R {sub vir}){sup –0.8±0.3}. Our derived gas volume densities are several orders of magnitude lower than predictions from standard two-phase models with a cool medium in pressure equilibrium with a hot, coronal medium expected in virialized halos at this mass scale. Applying the ionization corrections to the H I column densities, we estimate a lower limit to the cool gas mass M{sub CGM}{sup cool}>6.5×10{sup 10} M {sub ☉} for the volume within R < R {sub vir}. Allowing for an additional warm-hot, O VI-traced phase, the CGM accounts for at least half of the baryons purported to be missing from dark matter halos at the 10{sup 12} M {sub ☉} scale.

  1. Forged in FIRE: cusps, cores and baryons in low-mass dwarf galaxies

    Science.gov (United States)

    Oñorbe, Jose; Boylan-Kolchin, Michael; Bullock, James S.; Hopkins, Philip F.; Kereš, Dušan; Faucher-Giguère, Claude-André; Quataert, Eliot; Murray, Norman

    2015-12-01

    We present multiple ultrahigh resolution cosmological hydrodynamic simulations of M⋆ ≃ 104-6.3 M⊙ dwarf galaxies that form within two Mvir = 109.5-10 M⊙ dark matter halo initial conditions. Our simulations rely on the Feedback in Realistic Environments (FIRE) implementation of star formation feedback and were run with high enough force and mass resolution to directly resolve structure on the ˜200 pc scales. The resultant galaxies sit on the M⋆ versus Mvir relation required to match the Local Group stellar mass function via abundance matching. They have bursty star formation histories and also form with half-light radii and metallicities that broadly match those observed for local dwarfs at the same stellar mass. We demonstrate that it is possible to create a large (˜1 kpc) constant-density dark matter core in a cosmological simulation of an M⋆ ≃ 106.3 M⊙ dwarf galaxy within a typical Mvir = 1010 M⊙ halo - precisely the scale of interest for resolving the `too big to fail' problem. However, these large cores are not ubiquitous and appear to correlate closely with the star formation histories of the dwarfs: dark matter cores are largest in systems that form their stars late (z ≲ 2), after the early epoch of cusp building mergers has ended. Our M⋆ ≃ 104 M⊙ dwarf retains a cuspy dark matter halo density profile that matches that of a dark-matter-only run of the same system. Though ancient, most of the stars in our ultrafaint form after reionization; the ultraviolet field acts mainly to suppress fresh gas accretion, not to boil away gas that is already present in the protodwarf.

  2. Intermediate Mass Dilepton Production in an Expanding Baryon-rich Quark-Gluon Matter

    Institute of Scientific and Technical Information of China (English)

    HE Ze-Jun; JIANG Wei-Zhou; ZHOU Wen-Jie

    2001-01-01

    The intermediate mass dileptons from the quark phase, secondary hadronic processes and background sources have been studied based on a relativistic hydrodynamic model. Due to the effect of the phase boundary on the evolution of the system the contribution from the quark phase is much more important than that from secondary processes and is even comparable with that from background sources. This leads to a spectrum without the obvious humps of the hadronic phase contribution and the yield increasing with the incident energy of colliding nuclei. It is shown that the enhancement of dileptons is a signature for the formation of the quark-gluon plasma.PACS: 25. 75. Dw, 12. 38. Mh, 24. 10. Nz

  3. Measurement of b-Baryons with the CDF II detector

    Energy Technology Data Exchange (ETDEWEB)

    Heuser, Joachim; /Karlsruhe U., EKP

    2007-10-01

    We report the observation of new bottom baryon states. The most recent result is the observation of the baryon {Xi}{sub b}{sup -} through the decay {Xi}{sub b}{sup -} {yields} J/{psi}{Xi}{sup -}. The significance of the signal corresponds to 7.7{sigma} and the {Xi}{sub b}{sup -} mass is measured to be 5792.9{+-}2.5(stat.){+-}1.7(syst.) MeV/c{sup 2}. In addition we observe four resonances in the {Lambda}{sub b}{sup 0}{pi}{sup {+-}} spectra, consistent with the bottom baryons {Sigma}{sub b}{sup (*){+-}}. All observations are in agreement with theoretical expectations.

  4. Study of Baryon Spectroscopy Using a New Potential Form

    Directory of Open Access Journals (Sweden)

    L. I. Abou-Salem

    2014-01-01

    Full Text Available In the present work, the nonrelativistic quark model is applied to study baryon systems, where the constituent quarks are bound by a suitable hyper central potential. We proposed a new phenomenological form of the interaction potential, digamma-type potential. Using the Jacobi coordinates, the three-body wave equation is solved numerically to calculate the resonance states of the N, Δ, Λ, and Σ baryon systems. The present model contains only two adjustable parameters in addition to the quark masses. Our theoretical calculations are compared to the available experimental data and Cornell potential results. The description of the spectrum shows that the ground states of the considered light and strange baryon spectra are in general well reproduced.

  5. The role of pattern recognition in the computer-aided classification of mass spectra

    International Nuclear Information System (INIS)

    The requirement for the use of pattern recognition techniques as an aid in the identification of chemical substances from their mass spectra are reviewed. Decision-tree pattern recognition is recommended as potentially satisfying these requirements. Examples of this approach using a large data base of mass spectra are provided. (Auth.)

  6. Representations of the U$_{q}$(u$_{4,1}$) and a q-polynomial that determines baryon mass sum rules

    CERN Document Server

    Gavrilik, A M; Tertychnyj, A V; Gavrilik, A M; Kachurik, I I; Tertychnyj, A V

    1995-01-01

    With quantum groups U_q(su_n) taken as classifying symmetries for hadrons of n flavors, we calculate within irreducible representation D^+_{12}(p-1,p-3,p-4;p,p-2) (p \\in {\\bf Z}) of 'dynamical' quantum group U_q(u_{4,1}) the masses of baryons {1\\over 2}^+ that belong to {\\it 20}-plet of U_q(su_4). The obtained q-analog of mass relation (MR) for U_q(su_3)-octet contains unexpected mass-dependent term multiplied by the factor {A_q\\over B_q} where A_q, B_q are certain polynomials (resp. of 7-th and 6-th order) in the variable q+q^{-1}\\equiv [2]_q. Both values q=1 and q=e^{i\\pi \\over 6} turn the polynomial A_q into zero. But, while q=1 results in well-known Gell-Mann--Okubo (GMO) baryon MR, the second root of A_q reduces the q-MR to some novel mass sum rule which has irrational coefficients and which holds, for empirical masses, even with better accuracy than GMO mass sum rule.

  7. Galaxy Cluster Baryon Fractions Revisited

    CERN Document Server

    Gonzalez, Anthony H; Zabludoff, Ann I; Zaritsky, Dennis

    2013-01-01

    We measure the baryons contained in both the stellar and hot gas components for twelve galaxy clusters and groups at z~0.1 with M=1-5e14 Msun. This paper improves upon our previous work through the addition of XMM data, enabling measurements of the total mass and masses of each major baryonic component --- ICM, intracluster stars, and stars in galaxies --- for each system. We recover a relation for the stellar mass versus halo mass consistent with our previous result. We confirm that the partitioning of baryons between the stellar and hot gas components is a strong function of M500; the fractions of total mass in stars and X-ray gas within r500 scale as M500^-0.45 and M500^0.26, respectively. We also confirm that the combination of the BCG and intracluster stars is an increasingly important contributor to the stellar baryon budget in lower halo masses. We find a weak, but statistically significant, dependence of the total baryon fraction upon halo mass, scaling as M500^0.16. For M500>2e14, the total baryon fr...

  8. One-baryon spectrum and analytical properties of one-baryon dispersion curves in 3 + 1 dimensional strongly coupled lattice QCD with three flavors

    Science.gov (United States)

    Faria da Veiga, Paulo A.; O'Carroll, Michael; Valencia Alvites, José C.

    2016-03-01

    Considering a 3 + 1 dimensional lattice quantum chromodynamics (QCD) model defined with the improved Wilson action, three flavors, and 4 × 4 Dirac spin matrices, in the strong coupling regime, we reanalyze the question of the existence of the eightfold way baryons and complete our previous work where the existence of isospin octet baryons was rigorously solved. Here, we show the existence of isospin decuplet baryons which are associated with isolated dispersion curves in the subspace of the underlying quantum mechanical Hilbert space with vectors constructed with an odd number of fermion and antifermion basic quark and antiquark fields. Moreover, smoothness properties for these curves are obtained. The present work deals with a case for which the traditional method to solve the implicit equation for the dispersion curves, based on the use of the analytic implicit function theorem, cannot be applied. We do not have only one but two solutions for each one-baryon decuplet sector with fixed spin third component. Instead, we apply the Weierstrass preparation theorem, which also provides a general method for the general degenerate case. This work is completed by analyzing a spectral representation for the two-baryon correlations and providing the leading behaviors of the field strength normalization and the mass of the spectral contributions with more than one-particle. These are needed results for a rigorous analysis of the two-baryon and meson-baryon particle spectra.

  9. Baryon structure

    International Nuclear Information System (INIS)

    A brief review on the theoretical and experimental situation of baryon spectroscopy is first given. Then, the radial structure of baryons, related to the ground state form factors and the baryonic compressibility, is discussed. An experiment has been performed at Saturne laboratory (France) in which for the first time a compression of the nucleon is observed, exciting the P11 (1440 MeV) resonance (Roper resonance) by α-particles. The analysis of the data indicates that this excitation covers a large fraction of the available monopole strength in the nucleon. The derived compressibility is discussed as well as the consequence for other fields, as nuclear medium effects on baryon properties, high density phenomena in nuclear collisions as well as colour transparency. In the last point the spin-flip structure of the P11 (1440 MeV) resonance is discussed. The possibility to determine isoscalar spin-flip strength by polarized deuteron scattering is contrasted with first preliminary results from photon-induced reactions studied at Mainz which indicate a non-negligible M1 excitation of the Roper resonance. (author) 10 figs., 31 refs

  10. Alternative large Nc baryons and holography

    International Nuclear Information System (INIS)

    In gauge theories in the limit of a large number Nc of colors baryons are usually described as heavy solitonic objects with mass of order Nc. We discuss an alternative large Nc description both directly in the field theory as well as using holography. In this alternative large Nc limit at least some of the baryons behave like mesons, that is they stay light even at large Nc and their interactions vanish in that limit. For Nc=3 these alternative large Nc baryons are equivalent to the standard baryons. In the holographic description it is manifest that the Regge slopes of mesons and alternative baryons are degenerate.

  11. Alternative large Nc baryons and holography

    CERN Document Server

    Hoyos-Badajoz, Carlos

    2009-01-01

    In gauge theories in the limit of a large number Nc of colors, baryons are usually described as heavy solitonic objects with mass of order Nc. We discuss an alternative large Nc description both directly in the field theory as well as using holography. In this alternative large Nc limit at least some of the baryons behave like mesons, that is they stay light even at large Nc and their interactions vanish in that limit. For Nc=3 these alternative large Nc baryons are equivalent to the standard baryons. In the holographic description it is manifest that the Regge slopes of mesons and alternative baryons are degenerate.

  12. Local thermal equilibrium of dense baryonic matter at CBM experiment

    International Nuclear Information System (INIS)

    The Compressed Baryonic Matter (CBM) experiment at FAIR/GSI laboratory is being designed to perform heavy-ion collisions in fixed target mode at beam energies of 5-45 GeV per nucleon. The major scientific issues addressed in the experiment are the properties of quantum chromodynamics (QCD) at high baryon density and moderate temperature and the order of quark-hadron phase transition at large baryo-chemical potential. However an important question arises whether the dense baryonic matter created in such collisions may achieve a local thermal equilibrium or not. We have investigated the conditions of local thermal equilibrium of baryons and mesons in a small element of volume within the rapidity range |y| <1.0 for central Au+Au collisions at Elab = 10, 20, 30, 40 GeV per nucleon. For this purpose we used the microscopic transport model UrQMD-3.3 in default cascade mode. We calculated the longitudinal-to-transverse pressure anisotropy (PL/PT) and the inverse slope parameter of energy spectra of baryons and mesons inside the cell at different times (t)= 1-15 fm/c measured in center of mass frame. The quantities are averaged over 60 K events at every time step

  13. Baryon asymmetry in inflationary universe

    International Nuclear Information System (INIS)

    The problem of the baryon asymmetry in inflationary universe is discussed. It is shown that the baryon asymmetry in inflationary universe under certain constrainsts on masses of superheavy bosons can be larger than that in the standard scenario. An important property of the model considered is that the final baryon asymmetry does not depend on initial conditions in the early universe in contrast to what occUrs in the standard scenario based on (B-L) conserving grand unified theories. The new scenario is realized in the framework of the SU(5) Coleman-Weinberg theory with the symmetry breaking

  14. Relativistic three-body quark model of light baryons based on hypercentral approach

    International Nuclear Information System (INIS)

    In this paper, we have treated the light baryons as a relativistic three-body bound system. Inspired by lattice QCD calculations, we treated baryons as a spin-independent three-quark system within a relativistic three-quark model based on the three-particle Klein–Gordon equation. We presented the analytical solution of three-body Klein–Gordon equation with employing the constituent quark model based on a hypercentral approach through which two- and three-body forces are taken into account. Herewith the average energy values of the up, down and strange quarks containing multiplets are reproduced. To describe the hyperfine structure of the baryon, the splittings within the SU(6)-multiplets are produced by the generalized Gursey Radicati mass formula. The considered SU(6)-invariant potential is popular “Coulomb-plus-linear” potential and the strange and non-strange baryons spectra are in general well reproduced. (author)

  15. Search for an exotic S=-2, Q=-2 baryon resonance at a mass near 1862 MeV in quasi-real photoproduction

    CERN Document Server

    Airapetian, A; Akopov, Z; Amarian, M; Ammosov, V V; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Baturin, V; Baumgarten, C; Beckmann, M; Belostotskii, S; Bernreuther, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Bouwhuis, M; Brack, J; Brüll, A; Bryzgalov, V V; Capitani, G P; Chiang, H C; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; De Leo, R; De Nardo, L; De Sanctis, E; Devitsin, E G; Di Nezza, P; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G M; Ellinghaus, F; Elschenbroich, U; Ely, J; Fabbri, R; Fantoni, A; Feshchenko, A; Felawka, L; Fox, B; Franz, J; Frullani, S; Gärber, Y; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Garutti, E; Gaskell, D; Gavrilov, G E; Karibian, V; Graw, G; Grebenyuk, O; Greeniaus, L G; Hafidi, K; Hartig, M; Hasch, D; Heesbeen, D; Henoch, M; Hertenberger, R; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Kinney, E; Kiselev, A; Königsmann, K C; Kopytin, M; Korotkov, V A; Kozlov, V; Krauss, B; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Laziev, A; Lenisa, P; Liebing, P; Lindemann, T; Lipka, K; Lorenzon, W; Lü, J; Maiheu, B; Makins, N C R; Marianski, B; Marukyan, H O; Masoli, F; Mexner, V; Meyners, N; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Nass, A; Negodaev, M A; Nowak, Wolf-Dieter; Oganessyan, K; Ohsuga, H; Orlandi, G; Pickert, N; Potashov, S Yu; Potterveld, D H; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubacek, L; Ryckbosch, D; Salomatin, Yu I; Sanjiev, I; Savin, I; Scarlett, C; Schäfer, A; Schill, C; Schnell, G; Schüler, K P; Schwind, A; Seele, J; Seidl, R; Seitz, B; Shanidze, R G; Shearer, C; Shibata, T A; Shutov, V B; Simani, M C; Sinram, K; Stancari, M D; Statera, M; Steffens, E; Steijger, J J M; Stewart, J; Stösslein, U; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Tkabladze, A V; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Vetterli, Martin C; Vikhrov, V; Vincter, M G; Visser, J; Vogel, C; Vogt, M; Volmer, J; Weiskopf, C; Wendland, J; Wilbert, J; Ybeles-Smit, G V; Yen, S; Zihlmann, B; Zohrabyan, H G; Zupranski, P

    2004-01-01

    A search for an exotic baryon resonance with $S=-2, Q=-2$ has been performed in quasi-real photoproduction on a deuterium target through the decay channel $\\Xi^- \\pi^- \\to \\Lambda \\pi^- \\pi^- \\to p \\pi^- \\pi^- \\pi^-$. No evidence for a previously reported $\\Xi^{--}(1860)$ resonance is found in the $\\Xi^- \\pi^-$invariant mass spectrum. An upper limit for the photoproduction cross section of 2.1 nb is found at the 90% confidence level. The photoproduction cross section for the $\\Xi^{0}(1530)$ is found to be between 9 and 24 nb.

  16. Differentiating samples and experimental protocols by direct comparison of tandem mass spectra

    DEFF Research Database (Denmark)

    van der Plas-Duivesteijn, Suzanne J.; Wulff, Tune; Klychnikov, Oleg;

    2016-01-01

    Peptide tandem mass spectra can be analyzed by a number of means. They can be compared against predicted spectra of peptides derived from genome sequences, compared against previously acquired and identified spectra, or - sometimes - sequenced de novo. We recently introduced another method which...... compares spectra between liquid chromatography/tandem mass spectrometry (LC/MS/MS) datasets to determine the shared spectral content, and demonstrated how this can be applied in a molecular phylogenetic study using sera from human and non-human primates. We will here explore if such a method have other...... aiming for quality control of two traceable protein reference standards (troponin) used in clinical chemistry assays, by analysing the effect of storage conditions. The results illustrate a broad applicability of the metric based on shared tandem mass spectra between LC/MS/MS datasets for analysing...

  17. Galaxy cluster baryon fractions revisited

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Anthony H. [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States); Sivanandam, Suresh; Zabludoff, Ann I.; Zaritsky, Dennis [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

    2013-11-20

    We measure the baryons contained in both the stellar and hot-gas components for 12 galaxy clusters and groups at z ∼ 0.1 with M = 1-5 × 10{sup 14} M {sub ☉}. This paper improves upon our previous work through the addition of XMM-Newton X-ray data, enabling measurements of the total mass and masses of each major baryonic component—intracluster medium, intracluster stars, and stars in galaxies—for each system. We recover a mean relation for the stellar mass versus halo mass, M{sub ⋆}∝M{sub 500}{sup −0.52±0.04}, that is 1σ shallower than in our previous result. We confirm that the partitioning of baryons between the stellar and hot-gas components is a strong function of M {sub 500}; the fractions of total mass in stars and X-ray gas within a sphere of radius r {sub 500} scale as f{sub ⋆}∝M{sub 500}{sup −0.45±0.04} and f{sub gas}∝M{sub 500}{sup 0.26±0.03}, respectively. We also confirm that the combination of the brightest cluster galaxy and intracluster stars is an increasingly important contributor to the stellar baryon budget in lower halo masses. Studies that fail to fully account for intracluster stars typically underestimate the normalization of the stellar baryon fraction versus M {sub 500} relation by ∼25%. Our derived stellar baryon fractions are also higher, and the trend with halo mass weaker, than those derived from recent halo occupation distribution and abundance matching analyses. One difference from our previous work is the weak, but statistically significant, dependence here of the total baryon fraction upon halo mass: f{sub bary}∝M{sub 500}{sup 0.16±0.04}. For M {sub 500} ≳ 2 × 10{sup 14}, the total baryon fractions within r {sub 500} are on average 18% below the universal value from the seven year Wilkinson Microwave Anisotropy Probe (WMAP) analysis, or 7% below for the cosmological parameters from the Planck analysis. In the latter case, the difference between the universal value and cluster baryon fractions is

  18. De Novo Correction of Mass Measurement Error in Low Resolution Tandem MS Spectra for Shotgun Proteomics

    Science.gov (United States)

    Egertson, Jarrett D.; Eng, Jimmy K.; Bereman, Michael S.; Hsieh, Edward J.; Merrihew, Gennifer E.; MacCoss, Michael J.

    2012-12-01

    We report an algorithm designed for the calibration of low resolution peptide mass spectra. Our algorithm is implemented in a program called FineTune, which corrects systematic mass measurement error in 1 min, with no input required besides the mass spectra themselves. The mass measurement accuracy for a set of spectra collected on an LTQ-Velos improved 20-fold from -0.1776 ± 0.0010 m/z to 0.0078 ± 0.0006 m/z after calibration (avg ± 95 % confidence interval). The precision in mass measurement was improved due to the correction of non-linear variation in mass measurement accuracy across the m/z range.

  19. The Klein paradox and the mass spectra of the neutral vector mesons

    International Nuclear Information System (INIS)

    We use Dirac's equation with a long range harmonic potential to obtain the mass spectra of the neutral vector mesons rho0, ω, PHI, Ksup(0*) and psi. Our predictions are in fairly good agreement with the experimental results. (author)

  20. Excited baryons

    International Nuclear Information System (INIS)

    The status of the theory of the low-energy approach to hadron structure is reviewed briefly by surveying a few relevant models. A few examples of tests needed to sort out the predictions of different models pertaining to the quark-gluon structure of hadrons are discussed, and given the resulting physics objectives, a few experimental options for excited baryon research at CFBAF are suggested

  1. Excitations of strange bottom baryons

    CERN Document Server

    Woloshyn, R M

    2016-01-01

    The ground state and first excited state masses of Omega(b) and Omega(bb) baryons are calculated in lattice QCD using dynamical 2+1 flavour gauge fields. A set of baryon operators employing different combinations of smeared quark fields was used in the framework of the variational method. Results for radial excitation energies were confirmed by carrying out a supplementary multiexponential fitting analysis. Comparison is made with quark model calculations.

  2. Anomalous Dimensions of Conformal Baryons

    CERN Document Server

    Pica, Claudio

    2016-01-01

    We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small for a wide range of number of flavours. We also find that this is always smaller than the anomalous dimension of the fermion mass operator. These findings challenge the partial compositeness paradigm.

  3. Strangeness in the baryon ground states

    CERN Document Server

    Semke, A

    2012-01-01

    We compute the strangeness content of the baryon ground states based on an analysis of recent lattice simulations of the BMW, PACS, LHPC and HSC groups for the pion-mass dependence of the baryon masses. Our results rely on the relativistic chiral Lagrangian and large-$N_c$ sum rule estimates of the counter terms relevant for the baryon masses at N$^3$LO. A partial summation is implied by the use of physical baryon and meson masses in the one-loop contributions to the baryon self energies. A simultaneous description of the lattice results of the BMW, LHPC, PACS and HSC groups is achieved. We predict the pion- and strangeness sigma terms and the pion-mass dependence of the octet and decuplet ground states at different strange quark masses.

  4. Optimum Metallic-Bond Scheme: A Quantitative Analysis of Mass Spectra of Sodium Clusters

    Institute of Scientific and Technical Information of China (English)

    苏长荣; 李家明

    2001-01-01

    Based on the results of the optimum metallic-bond scheme for sodium clusters, we present a quantitative analysis of the detailed features of the mass spectra of sodium clusters. We find that, in the generation of sodium clusters with various abundances, the quasi-steady processes through adding or losing a sodium atom dominate. The quasi-steady processes through adding or losing a sodium dimer are also important to understand the detailed features of mass spectra for small clusters.

  5. Search and decoy: the automatic identification of mass spectra.

    Science.gov (United States)

    Eisenacher, Martin; Kohl, Michael; Turewicz, Michael; Koch, Markus-Hermann; Uszkoreit, Julian; Stephan, Christian

    2012-01-01

    In recent years, the generation and interpretation of MS/MS spectra for the identification of peptides and proteins has matured to a frequently used automatic workflow in Proteomics. Several software solutions for the automated analysis of MS/MS spectra allow for high-throughput/high-performance analyses of complex samples. Related to MS/MS searches, target-decoy approaches have gained more and more popularity: in a "decoy" part of the search database nonexistent sequences mimic real sequences (the "target" sequences). With their help, the number of falsely identified peptides/proteins can be estimated after a search and the resulting protein list can be cut at a specified false discovery rate (FDR). This is an essential prerequisite for all quantitative approaches, as they rely on correct identifications. Especially the label-free approach "spectral counting"-gaining more and more popularity due to low costs and simplicity-depends directly on the correctness of peptide-spectrum matches (PSMs). This work's aim is to describe five popular search engines-especially their general properties regarding protein identification, but also their quantification abilities, if those go beyond spectral counting. By doing so, Proteomics researchers are enabled to compare their features and to choose an appropriate solution for their specific question. Furthermore, the search engines are applied to a spectrum data set generated from a complex sample with a Thermo LTQ Velos OrbiTrap (Thermo Fisher Scientific, Waltham, MA, USA). The results of the search engines are compared, e.g., regarding time requirements, peptides and proteins found, and the search engines' behavior using the decoy approach. PMID:22665317

  6. Heavy baryons in the relativistic quark model

    International Nuclear Information System (INIS)

    In the framework of the relativistic quasipotential quark model the mass spectrum of baryons with two heavy quarks is calculated. The quasipotentials for interactions of two quarks and of a quark with a scalar and axial vector diquark are evaluated. The bound state masses of baryons with JP=1/2+, 3/2+ are computed. (orig.)

  7. Shadows of Relic Neutrino Masses and Spectra on Highest Energy GZK Cosmic Rays

    CERN Document Server

    Fargion, D; De Sanctis-Lucentini, P G; Troia, C D; Konoplich, R V

    2001-01-01

    The Ultra High Energy (UHE) neutrino scattering onto relic cosmic neutrinos in galactic and local halos offers an unique way to overcome GZK cut-off. The UHE nu secondary of UHE photo-pion decays may escape the GZK cut-off and travel on cosmic distances hitting local light relic neutrinos clustered in dark halos. The Z resonant production and the competitive W^+W^-, ZZ pair production define a characteristic imprint on hadronic consequent UHECR spectra. This imprint keeps memory both of the primary UHE nu spectra as well as of the possible relic neutrino masses values, energy spectra and relic densities. Such an hadronic showering imprint should reflect into spectra morphology of cosmic rays near and above GZK 10^{19}-10^{21}eV cut-off energies. A possible neutrino degenerate masses at eVs or a more complex and significant neutrino mass split below or near Super-Kamiokande \\triangle m_{\

  8. Unified Explanation of Quark-Lepton Mass Spectra in q-Deformed Quantum Mechanics

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-Zu

    2000-01-01

    The quark-lepton mass spectra in q-deformed quantum mechanics are investigated. The theoretical formula of the spectrum includes two new quantum numbers: the q-exciting number n describing generations and the scaling indexes Mi describing families. This formula shows two exponential increases in the mass distribution as generation n increases, the intervals of masses in a given family exponentially increase, and the mass splittings among different members in a generation also exponentially increase. The theoretical values of masses o[ quarks and leptons reasonably agree with the experimental data except for the electron mass which is one order larger.

  9. Strange and non-strange baryon and antibaryon production in sulphur-tungsten and sulphur-sulphur interactions at 200 A Gev/c

    International Nuclear Information System (INIS)

    The author has studied production of strange and multistrange baryons and antibaryons in central sulphur-tungsten, sulphur-sulphur, and lead-lead interactions at relativistic energies. The spectra of strange baryons and antibaryons provide information about the dynamics of hadronic matter under the extreme conditions realised in these collisions. The particle ratios allow the degree and the nature of the flavour equilibrium to be studied, while the transverse mass distributions provide independent information of the temperatures achieved. 143 refs

  10. Interpretation of temperature-dependent photoionization mass spectra of n-hexane, cyclohexane, and diethyl ether

    International Nuclear Information System (INIS)

    The mass spectra of vapor-phase n-hexane, cyclohexane, and diethyl ether are measured as a function of temperature by photoionization mass spectrometry. Three fixed wavelengths are used, the Kr I, Ar I, and Ne I resonance lines. The results are interpreted on the basis of a simplified version of the quasi-equilibrium theory. In this model it is assumed that the density of states of a transition state can be described by the density of states of the neutral molecule multiplied by a phase space scaling factor. The phase space scaling factors are fitted for an optimum reconstruction of the photon and temperature-dependent mass spectra. The knowledge obtained about the fragmentation reaction rates of n-hexane is applied to field ionization mass spectra, which results in an estimate of the average energy deposition in the molecular ion of 0.77 ± 0.1 eV

  11. Large-Scale Distribution of Total Mass versus Luminous Matter from Baryon Acoustic Oscillations: First Search in the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey Data Release 10

    Science.gov (United States)

    Soumagnac, M. T.; Barkana, R.; Sabiu, C. G.; Loeb, A.; Ross, A. J.; Abdalla, F. B.; Balan, S. T.; Lahav, O.

    2016-05-01

    Baryon acoustic oscillations in the early Universe are predicted to leave an as yet undetected signature on the relative clustering of total mass versus luminous matter. A detection of this effect would provide an important confirmation of the standard cosmological paradigm and constrain alternatives to dark matter as well as nonstandard fluctuations such as compensated isocurvature perturbations (CIPs). We conduct the first observational search for this effect, by comparing the number-weighted and luminosity-weighted correlation functions, using the SDSS-III BOSS Data Release 10 CMASS sample. When including CIPs in our model, we formally obtain evidence at 3.2 σ of the relative clustering signature and a limit that matches the existing upper limits on the amplitude of CIPs. However, various tests suggest that these results are not yet robust, perhaps due to systematic biases in the data. The method developed in this Letter used with more accurate future data such as that from DESI, is likely to confirm or disprove our preliminary evidence.

  12. Photoproduction of charmed baryons

    International Nuclear Information System (INIS)

    The results of a search for the photoproduction of charmed baryons in the broad-band neutral beam at Fermi National Accelerator Laboratory are reported. The lowest lying charmed baryon (Λ/sub c/+) is observed through its decay to p-anti K0. The cross section times branching ratio of γ + C → Λ/sub c/+ + X, γ + C → p + anti K0 is measured to be sigma B = 3 nanobarns/nucleon. The total error on this measurement is estimated to be -20% to +40%. The mass of the Λ/sub c/+ is found to be 2.284 +- 0.001 GeV/c2, in good agreement with the Mark II result from SPEAR. Upper limits (90% confidence level) are set on sigma B for the modes Λ0π, Λ0πππ, pKπ

  13. Baryonic Popcorn

    CERN Document Server

    Kaplunovsky, Vadim; Sonnenschein, Jacob

    2012-01-01

    In the large N limit cold dense nuclear matter must be in a lattice phase. This applies also to holographic models of hadron physics. In a class of such models, like the generalized Sakai-Sugimoto model, baryons take the form of instantons of the effective flavor gauge theory that resides on probe flavor branes. In this paper we study the phase structure of baryonic crystals by analyzing discrete periodic configurations of such instantons. We find that instanton configurations exhibit a series of "popcorn" transitions upon increasing the density. Through these transitions normal (3D) lattices expand into the transverse dimension, eventually becoming a higher dimensional (4D) multi-layer lattice at large densities. We consider 3D lattices of zero size instantons as well as 1D periodic chains of finite size instantons, which serve as toy models of the full holographic systems. In particular, for the finite-size case we determine solutions of the corresponding ADHM equations for both a straight chain and for a 2...

  14. Mass spectra of proteins and other biomolecules recorded using a handheld instrument

    Science.gov (United States)

    Janfelt, Christian; Talaty, Nari; Mulligan, Christopher C.; Keil, Adam; Ouyang, Zheng; Cooks, R. Graham

    2008-12-01

    Proteins (myoglobin and cytochrome C), peptides (bradykinin and melittin), alkaloids in complex plant materials, and mixtures of phospholipids from a bacterial extract all give characteristic electrospray mass spectra using a handheld tandem mass spectrometer, Mini 10. The mass/charge range of the 10 kg Mini 10 was extended to m/z 2000 using resonant ion ejection at low frequency allowing analysis of proteins with molecular weights up to 17,000 Da. Fragmentation of peptides and proteins was observed.

  15. On light baryons and their excitations

    CERN Document Server

    Eichmann, Gernot; Sanchis-Alepuz, Helios

    2016-01-01

    We study ground states and excitations of light octet and decuplet baryons within the framework of Dyson-Schwinger and Faddeev equations. We improve upon similar approaches by explicitly taking into account the momentum-dependent dynamics of the quark-gluon interaction that leads to dynamical chiral symmetry breaking. We perform calculations in both the three-body Faddeev framework and the quark-diquark approximation in order to assess the impact of the latter on the spectrum. Our results indicate that both approaches agree well with each other. The resulting spectra furthermore agree one-to-one with experiment, provided well-known deficiencies of the rainbow-ladder approximation are compensated for. We also discuss the mass evolution of the Roper and the excited Delta with varying pion mass and analyse the internal structure in terms of their partial wave decompositions.

  16. Baryons in AdS/QCD

    CERN Document Server

    Hong, D K; Yee, H U; Hong, Deog Ki; Inami, Takeo; Yee, Ho-Ung

    2007-01-01

    We construct a holographic model for baryons in the context of AdS/QCD and study the spin-1/2 nucleon spectra and its couplings to mesons, taking fully account of the effects from the chiral symmetry breaking. A pair of 5D spinors is introduced to represent both left and right chiralities. Our model contains two adjustable parameters, the infrared cutoff and the Yukawa coupling of bulk spinors to bulk scalars, corresponding to the order parameter of chiral symmetry. Taking the lowest-lying nucleon mass as an input, we calculate the mass spectrum of excited nucleons and the nucleon couplings to pions. The excited nucleons show a parity-doubling pattern with smaller pion-nucleon couplings.

  17. Determination in gas chromatography-mass spectrometry data of mass spectra free of background and neighboring substance contributions

    International Nuclear Information System (INIS)

    The determination in a g.c.-m.s. data matrix by singular value analysis and least squares of the mass spectra of the substances present and of their corresponding resolved g.c. peak profiles has been supplemented by the determination of a background for each mass, assumed to be constant over 10-12 contiguous scans. The norm for the g.c. peaks has been changed to a maximum of one so that the mass spectral intensities are proportional to the true ion currents at the respective g.c. peak maxima. Complete resolved spectra are computed by using all measured masses. Examples are given of close resolutions (less than one scan separation) and multiple overlap resolution (8 overlapping substances). The method is compared with other published clean-up methods. (Auth.)

  18. Improved Peak Detection and Deconvolution of Native Electrospray Mass Spectra from Large Protein Complexes

    Science.gov (United States)

    Lu, Jonathan; Trnka, Michael J.; Roh, Soung-Hun; Robinson, Philip J. J.; Shiau, Carrie; Fujimori, Danica Galonic; Chiu, Wah; Burlingame, Alma L.; Guan, Shenheng

    2015-12-01

    Native electrospray-ionization mass spectrometry (native MS) measures biomolecules under conditions that preserve most aspects of protein tertiary and quaternary structure, enabling direct characterization of large intact protein assemblies. However, native spectra derived from these assemblies are often partially obscured by low signal-to-noise as well as broad peak shapes because of residual solvation and adduction after the electrospray process. The wide peak widths together with the fact that sequential charge state series from highly charged ions are closely spaced means that native spectra containing multiple species often suffer from high degrees of peak overlap or else contain highly interleaved charge envelopes. This situation presents a challenge for peak detection, correct charge state and charge envelope assignment, and ultimately extraction of the relevant underlying mass values of the noncovalent assemblages being investigated. In this report, we describe a comprehensive algorithm developed for addressing peak detection, peak overlap, and charge state assignment in native mass spectra, called PeakSeeker. Overlapped peaks are detected by examination of the second derivative of the raw mass spectrum. Charge state distributions of the molecular species are determined by fitting linear combinations of charge envelopes to the overall experimental mass spectrum. This software is capable of deconvoluting heterogeneous, complex, and noisy native mass spectra of large protein assemblies as demonstrated by analysis of (1) synthetic mononucleosomes containing severely overlapping peaks, (2) an RNA polymerase II/α-amanitin complex with many closely interleaved ion signals, and (3) human TriC complex containing high levels of background noise.

  19. Re-hardening of hadron transverse mass spectra in relativistic heavy-ion collisions

    Indian Academy of Sciences (India)

    P K Sahu; N Otuka; M Isse; Y Nara; A Ohnishi

    2006-05-01

    We analyze the spectra of pions and protons in heavy-ion collisions at relativistic energies from 2 A GeV to 65+65 A GeV by using a jet-implemented hadron-string cascade model. In this energy region, hadron transverse mass spectra first show softening until SPS energies, and re-hardening may emerge at RHIC energies. Since hadronic matter is expected to show only softening at higher energy densities, this re-hardening of spectra can be interpreted as a good signature of the quark-gluon plasma formation.

  20. A computational framework for heparan sulfate sequencing using high-resolution tandem mass spectra

    DEFF Research Database (Denmark)

    Hu, Han; Huang, Yu; Mao, Yang;

    2014-01-01

    activities. Its biological activities depend on the fine structures of its protein-binding domains, the determination of which remains a daunting task. Methods have advanced to the point that mass spectra with information-rich product ions may be produced on purified HS saccharides. However, the...... interpretation of these complex product ion patterns has emerged as the bottleneck to the dissemination of these HS sequencing methods. To solve this problem, we designed HS-SEQ, the first comprehensive algorithm for HS de novo sequencing using high-resolution tandem mass spectra. We tested HS-SEQ using negative...... electron transfer dissociation (NETD) tandem mass spectra generated from a set of pure synthetic saccharide standards with diverse sulfation patterns. The results showed that HS-SEQ rapidly and accurately determined the correct HS structures from large candidate pools....

  1. Decuplet baryons in hot medium

    CERN Document Server

    Azizi, K

    2016-01-01

    The thermal properties of the light decuplet baryons are investigated in the framework of the thermal QCD sum rules. In particular, the behavior of the mass and residue of the $\\Delta$, $\\Sigma^{*}$, $\\Xi^{*}$ and $\\Omega$ baryons with respect to temperature are analyzed taking into account the additional operators coming up in the Wilson expansion at finite temperature. It is found that the mass and residue of these particles remain overall unaffected up to $T\\simeq150~MeV$ but, after this point, they start to diminish, considerably.

  2. Baryonic popcorn

    Science.gov (United States)

    Kaplunovsky, Vadim; Melnikov, Dmitry; Sonnenschein, Jacob

    2012-11-01

    In the large N c limit cold dense nuclear matter must be in a lattice phase. This applies also to holographic models of hadron physics. In a class of such models, like the generalized Sakai-Sugimoto model, baryons take the form of instantons of the effective flavor gauge theory that resides on probe flavor branes. In this paper we study the phase structure of baryonic crystals by analyzing discrete periodic configurations of such instantons. We find that instanton configurations exhibit a series of "popcorn" transitions upon increasing the density. Through these transitions normal (3D) lattices expand into the transverse dimension, eventually becoming a higher dimensional (4D) multi-layer lattice at large densities. We consider 3D lattices of zero size instantons as well as 1D periodic chains of finite size instantons, which serve as toy models of the full holographic systems. In particular, for the finite-size case we determine solutions of the corresponding ADHM equations for both a straight chain and for a 2D zigzag configuration where instantons pop up into the holographic dimension. At low density the system takes the form of an "abelian anti- ferromagnetic" straight periodic chain. Above a critical density there is a second order phase transition into a zigzag structure. An even higher density yields a rich phase space characterized by the formation of multi-layer zigzag structures. The finite size of the lattices in the transverse dimension is a signal of an emerging Fermi sea of quarks. We thus propose that the popcorn transitions indicate the onset of the "quarkyonic" phase of the cold dense nuclear matter.

  3. Improved method for estimating molecular weights of volatile organic compounds from low-resolution mass spectra

    Energy Technology Data Exchange (ETDEWEB)

    Scott, D.R.

    1991-01-01

    An improved method of estimating molecular weights of volatile organic compounds from their mass spectra has been developed and implemented with an expert system. The method is based on the strong correlation of MAXMASS, the highest mass with an intensity of 5% of the base peak in a mass spectrum, with the true molecular weight. Linear corrections to MAXMASS, which yield molecular weight estimates, were derived empirically using the expert system. The system is based on a sequential modular design with a primary classifier linked to molecular weight estimators for the resulting six classes. These are non-halobenzenes; chlorobenzenes; bromoalkenes/alkenes; mono- and dichloroalkanes/alkenes; tri-, tetra- and pentachloro-alkanes/alkenes; and others. Performance tests were made with the old and improved expert systems and the Self Training Interpretive and Retrieval System (STIRS) on NIST reference spectra of the 107 training compounds; on a set of 32 test NIST reference spectra of other compounds found in air samples; on a set of 100 randomly selected NIST reference spectra; and on 27 spectra taken from actual field gas chromatography/mass spectrometry samples.

  4. Pion mean fields and heavy baryons

    CERN Document Server

    Yang, Ghil-Seok; Polyakov, Maxim V; Praszałowicz, Michał

    2016-01-01

    We show that the masses of the lowest-lying heavy baryons can be very well described in a pion mean-field approach. We consider a heavy baryon as a system consisting of the $N_c-1$ light quarks that induce the pion mean field, and a heavy quark as a static color source under the influence of this mean field. In this approach we derive a number of \\textit{model-independent} relations and calculate the heavy baryon masses using those of the lowest-lying light baryons as input. The results are in remarkable agreement with the experimental data. In addition, the mass of the $\\Omega_b^*$ baryon is predicted.

  5. Improved mass resolution and mass accuracy in TOF-SIMS spectra and images using argon gas cluster ion beams.

    Science.gov (United States)

    Shon, Hyun Kyong; Yoon, Sohee; Moon, Jeong Hee; Lee, Tae Geol

    2016-06-01

    The popularity of argon gas cluster ion beams (Ar-GCIB) as primary ion beams in time-of-flight secondary ion mass spectrometry (TOF-SIMS) has increased because the molecular ions of large organic- and biomolecules can be detected with less damage to the sample surfaces. However, Ar-GCIB is limited by poor mass resolution as well as poor mass accuracy. The inferior quality of the mass resolution in a TOF-SIMS spectrum obtained by using Ar-GCIB compared to the one obtained by a bismuth liquid metal cluster ion beam and others makes it difficult to identify unknown peaks because of the mass interference from the neighboring peaks. However, in this study, the authors demonstrate improved mass resolution in TOF-SIMS using Ar-GCIB through the delayed extraction of secondary ions, a method typically used in TOF mass spectrometry to increase mass resolution. As for poor mass accuracy, although mass calibration using internal peaks with low mass such as hydrogen and carbon is a common approach in TOF-SIMS, it is unsuited to the present study because of the disappearance of the low-mass peaks in the delayed extraction mode. To resolve this issue, external mass calibration, another regularly used method in TOF-MS, was adapted to enhance mass accuracy in the spectrum and image generated by TOF-SIMS using Ar-GCIB in the delayed extraction mode. By producing spectra analyses of a peptide mixture and bovine serum albumin protein digested with trypsin, along with image analyses of rat brain samples, the authors demonstrate for the first time the enhancement of mass resolution and mass accuracy for the purpose of analyzing large biomolecules in TOF-SIMS using Ar-GCIB through the use of delayed extraction and external mass calibration. PMID:26861497

  6. Dirac mass spectra of Qanti q-like mesons in a power-law potential

    International Nuclear Information System (INIS)

    The mass spectra of Qanti q-like mesons are studied in the Dirac equation with an equally mixed 4-vector and scalar powerlaw potential of the form V(r)=Arsup(0.1) + V0. It is found that this flavor-independent potential can satisfactorily describe the mass levels of D, F and B mesons along with those of PSI and T families in a unified manner and that the quark masses in quarkonia and Qanti q-like mesons are very close to the current quark masses. (orig.)

  7. Multi-strange baryon production in pp collisions at √(s)=7 TeV with ALICE

    International Nuclear Information System (INIS)

    A measurement of the multi-strange Ξ- and Ω- baryons and their antiparticles by the ALICE experiment at the CERN Large Hadron Collider (LHC) is presented for inelastic proton-proton collisions at a centre-of-mass energy of 7 TeV. The transverse momentum (pT) distributions were studied at mid-rapidity (|y|T- and Ξ¯+ baryons, and in the range of 0.8T- and Ω¯+. Baryons and antibaryons were measured as separate particles and we find that the baryon to antibaryon ratio of both particle species is consistent with unity over the entire range of the measurement. The statistical precision of the current data has allowed us to measure a difference between the mean pT of Ξ- (Ξ¯+) and Ω- (Ω¯+). Particle yields, mean pT, and the spectra in the intermediate pT range are not well described by the PYTHIA Perugia 2011 tune Monte Carlo event generator, which has been tuned to reproduce the early LHC data. The discrepancy is largest for Ω-(Ω¯+). This PYTHIA tune approaches the pT spectra of Ξ- and Ξ¯+ baryons below pT- and Ξ¯+ spectra above pT>6.0 GeV/c. We also illustrate the difference between the experimental data and model by comparing the corresponding ratios of (Ω-+Ω¯+)/(Ξ-+Ξ¯+) as a function of transverse mass.

  8. Computational Prediction of Electron Ionization Mass Spectra to Assist in GC/MS Compound Identification.

    Science.gov (United States)

    Allen, Felicity; Pon, Allison; Greiner, Russ; Wishart, David

    2016-08-01

    We describe a tool, competitive fragmentation modeling for electron ionization (CFM-EI) that, given a chemical structure (e.g., in SMILES or InChI format), computationally predicts an electron ionization mass spectrum (EI-MS) (i.e., the type of mass spectrum commonly generated by gas chromatography mass spectrometry). The predicted spectra produced by this tool can be used for putative compound identification, complementing measured spectra in reference databases by expanding the range of compounds able to be considered when availability of measured spectra is limited. The tool extends CFM-ESI, a recently developed method for computational prediction of electrospray tandem mass spectra (ESI-MS/MS), but unlike CFM-ESI, CFM-EI can handle odd-electron ions and isotopes and incorporates an artificial neural network. Tests on EI-MS data from the NIST database demonstrate that CFM-EI is able to model fragmentation likelihoods in low-resolution EI-MS data, producing predicted spectra whose dot product scores are significantly better than full enumeration "bar-code" spectra. CFM-EI also outperformed previously reported results for MetFrag, MOLGEN-MS, and Mass Frontier on one compound identification task. It also outperformed MetFrag in a range of other compound identification tasks involving a much larger data set, containing both derivatized and nonderivatized compounds. While replicate EI-MS measurements of chemical standards are still a more accurate point of comparison, CFM-EI's predictions provide a much-needed alternative when no reference standard is available for measurement. CFM-EI is available at https://sourceforge.net/projects/cfm-id/ for download and http://cfmid.wishartlab.com as a web service. PMID:27381172

  9. Mass and Hot Baryons in Massive Galaxy Clusters from Subaru Weak-Lensing and AMiBA Sunyaev-Zel'Dovich Effect Observations

    Science.gov (United States)

    Umetsu, Keiichi; Birkinshaw, Mark; Liu, Guo-Chin; Wu, Jiun-Huei Proty; Medezinski, Elinor; Broadhurst, Tom; Lemze, Doron; Zitrin, Adi; Ho, Paul T. P.; Huang, Chih-Wei Locutus; Koch, Patrick M.; Liao, Yu-Wei; Lin, Kai-Yang; Molnar, Sandor M.; Nishioka, Hiroaki; Wang, Fu-Cheng; Altamirano, Pablo; Chang, Chia-Hao; Chang, Shu-Hao; Chang, Su-Wei; Chen, Ming-Tang; Han, Chih-Chiang; Huang, Yau-De; Hwang, Yuh-Jing; Jiang, Homin; Kesteven, Michael; Kubo, Derek Y.; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter; Raffin, Philippe; Wei, Tashun; Wilson, Warwick

    2009-04-01

    We present a multiwavelength analysis of a sample of four hot (TX > 8 keV) X-ray galaxy clusters (A1689, A2261, A2142, and A2390) using joint AMiBA Sunyaev-Zel'dovich effect (SZE) and Subaru weak-lensing observations, combined with published X-ray temperatures, to examine the distribution of mass and the intracluster medium (ICM) in massive cluster environments. Our observations show that A2261 is very similar to A1689 in terms of lensing properties. Many tangential arcs are visible around A2261, with an effective Einstein radius ~40'' (at z ~ 1.5), which when combined with our weak-lensing measurements implies a mass profile well fitted by a Navarro-Frenk-White model with a high concentration c vir ~ 10, similar to A1689 and to other massive clusters. The cluster A2142 shows complex mass substructure, and displays a shallower profile (c vir ~ 5), consistent with detailed X-ray observations which imply recent interaction. The AMiBA map of A2142 exhibits an SZE feature associated with mass substructure lying ahead of the sharp northwest edge of the X-ray core suggesting a pressure increase in the ICM. For A2390 we obtain highly elliptical mass and ICM distributions at all radii, consistent with other X-ray and strong-lensing work. Our cluster gas fraction measurements, free from the hydrostatic equilibrium assumption, are overall in good agreement with published X-ray and SZE observations, with the sample-averaged gas fraction of langf gas(baryon fraction fb = Ω b /Ω m constrained by the WMAP five-year data, this indicates langf gas,200rang/fb = 0.78 ± 0.16, i.e., (22 ± 16)% of the baryons are missing from the hot phase of clusters. Based in part on data collected at the Subaru Telescope, which is operated by the National Astronomical Society of Japan.

  10. Systematic Uncertainties in Black Hole Masses Determined from Single Epoch Spectra

    DEFF Research Database (Denmark)

    Denney, Kelly D.; Peterson, Bradley M.; Dietrich, Matthias;

    2008-01-01

    We explore the nature of systematic errors that can arise in measurement of black hole masses from single-epoch spectra of active galactic nuclei (AGNs) by utilizing the many epochs available for NGC 5548 and PG1229+204 from reverberation mapping databases. In particular, we examine systematics due...

  11. PATTERN RECOGNITION/EXPERT SYSTEM FOR IDENTIFICATION OF TOXIC COMPOUNDS FROM LOW RESOLUTION MASS SPECTRA

    Science.gov (United States)

    An empirical rule-based pattern recognition/expert system for classifying, estimating molecular weights and identifying low resolution mass spectra of toxic and other organic compounds has been developed and evaluated. he system was designed to accommodate low concentration spect...

  12. Charmed baryon decays observed in e+e- annihilation at SPEAR

    International Nuclear Information System (INIS)

    Various weak decays of the charmed baryon Λ/sub c/ are observed in the Mark II detector at the SLAC e+e- storage ring SPEAR. Hadronic decays Λ/sub c/+ → pK-π+ and Λ/sub c/+ → pK/sub s/0 and their conjugates are observed as peaks in invariant mass spectra at m(Λ/sub c/) = (2286 +- 6) MeV/c2. An estimate of the charmed baryon production cross section, sigma(Λ/sub c/) + sigma (anti Λ/sub c/) = (1.7 +- 0.4) nb, derived from Mark II measurements of the inclusive baryon cross sections R/sub p/ and R/sub Λ/ as functions of center-of-mass energy, is used to calculate branching ratios for these hadronic decays: BR (Λ/sub c/+ → p K- π+) = (2.0 +- 0.8)%; BR (Λ/sub c/+ → p k/sub s/0)/BR (Λ/sub c/+ → p K- π+) = (36 +- 16)%. An attempt is also made to observe higher mass charmed baryons by reconstructing cascade decays Σ/sub c/ → Λ/sub c/π. Evidence for the observation of semileptonic decays of the charmed baryon is presented. Direct electrons are observed in events containing antiprotons, lambdas and antilambdas. The number of electrons per baryon event, after background subtraction and efficiency correction, is used, together with an estimate of the charmed baryon content of proton and lambda events, to calculate inclusive and semi-inclusive semileptonic branching ratios of the Λ/sub c/

  13. Baryons and baryonic matter in four-fermion interaction models

    International Nuclear Information System (INIS)

    In this work we discuss baryons and baryonic matter in simple four-fermion interaction theories, the Gross-Neveu model and the Nambu-Jona-Lasinio model in 1+1 and 2+1 space-time dimensions. These models are designed as toy models for dynamical symmetry breaking in strong interaction physics. Pointlike interactions (''four-fermion'' interactions) between quarks replace the full gluon mediated interaction of quantum chromodynamics. We consider the limit of a large number of fermion flavors, where a mean field approach becomes exact. This method is formulated in the language of relativistic many particle theory and is equivalent to the Hartree-Fock approximation. In 1+1 dimensions, we generalize known results on the ground state to the case where chiral symmetry is broken explicitly by a bare mass term. For the Gross-Neveu model, we derive an exact self-consistent solution for the finite density ground state, consisting of a one-dimensional array of equally spaced potential wells, a baryon crystal. For the Nambu- Jona-Lasinio model we apply the derivative expansion technique to calculate the total energy in powers of derivatives of the mean field. In a picture akin to the Skyrme model of nuclear physics, the baryon emerges as a topological soliton. The solution for both the single baryon and dense baryonic matter is given in a systematic expansion in powers of the pion mass. The solution of the Hartree-Fock problem is more complicated in 2+1 dimensions. In the massless Gross-Neveu model we derive an exact self-consistent solution by extending the baryon crystal of the 1+1 dimensional model, maintaining translational invariance in one spatial direction. This one-dimensional configuration is energetically degenerate to the translationally invariant solution, a hint in favor of a possible translational symmetry breakdown by more general geometrical structures. In the Nambu-Jona-Lasinio model, topological soliton configurations induce a finite baryon number. In contrast

  14. Baryon superfluidity and neutrino emissivity of neutron stars

    OpenAIRE

    Takatsuka, T.; Tamagaki, R.

    2004-01-01

    For neutron stars with hyperon-mixed core, neutrino emissivity is studied under the equation of state, obtained by introducing repulsive three-body force universal for all baryons so as to assure the maximum mass compatible with the observation. By paying attention to the density-dependence of critical temperatures of baryon superfluids, which reflect the nature of baryon-baryon interaction and control neutron star cooling, we show what neutrino emission processes are efficient in the regions...

  15. The halo masses and galaxy environments of hyperluminous QSOs at z~2.7 in the Keck Baryonic Structure Survey

    CERN Document Server

    Trainor, Ryan F

    2012-01-01

    We present an analysis of the galaxy distribution surrounding 15 of the most luminous (>10^{14} L_sun; M_1450 ~ -30) QSOs in the sky with z~2.7. Our data are drawn from the Keck Baryonic Structure Survey (KBSS). In this work, we use the positions and spectroscopic redshifts of 1558 galaxies that lie within ~3', (4.2 h^{-1} comoving Mpc; cMpc) of the hyperluminous QSO (HLQSO) sightline in one of 15 independent survey fields, together with new measurements of the HLQSO systemic redshifts. We measure the galaxy-HLQSO cross-correlation function, the galaxy-galaxy autocorrelation function, and the characteristic scale of galaxy overdensities surrounding the sites of exceedingly rare, extremely rapid, black hole accretion. On average, the HLQSOs lie within significant galaxy overdensities, characterized by a velocity dispersion sigma_v ~ 200 km s^{-1} and a transverse angular scale of ~25", (~200 physical kpc). We argue that such scales are expected for small groups with log(M_h/M_sun)~13. The galaxy-HLQSO cross-co...

  16. Spectroscopy of doubly and triply-charmed baryons from lattice QCD

    CERN Document Server

    Padmanath, M; Mathur, Nilmani; Peardon, Michael

    2013-01-01

    We present the ground and excited state spectra of doubly and triply-charmed baryons by using lattice QCD with dynamical clover fermions. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) $\\otimes$ O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses. Using those splittings for doubly-charmed baryons, and taking input of experimental $B_c$ meson mass, we predict the mass splittings...

  17. Spectroscopy of doubly and triply-charmed baryons from lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Padmanath, M. [Tata Institute; Edwards, Robert G. [JLAB; Mathur, Nilmani [Tata Institute; Peardon, Michael [Trinity College, Dublin

    2013-11-01

    We present the ground and excited state spectra of doubly and triply-charmed baryons by using lattice QCD with dynamical clover fermions. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) Ⓧ O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses. Using those splittings for doubly-charmed baryons, and taking input of experimental Bc meson mass, we predict the mass splittings of B*c-Bc to be about 80 ± 8 MeV and mΩccb=8050±10 MeV.

  18. Some Like It Hot: Linking Diffuse X-ray Luminosity, Baryonic Mass, and Star Formation Rate in Compact Groups of Galaxies

    Science.gov (United States)

    Desjardins, Tyler D.; Gallagher, S.; Hornschemeier, A. E.; Mulchaey, J. S.; Walker, L.; Brandt, W. N.; Charlton, J. C.; Johnson, K. E.; Tzanavaris, P.

    2014-01-01

    Compact groups of galaxies (CGs) are ideal laboratories in which to study the effects of environmentally-driven galaxy evolution due to their high galaxy number densities and low velocity dispersions, which cause frequent and prolonged galaxy-galaxy interactions. In our study to better understand the origin and properties of hot gas in poor systems of galaxies, we present an analysis of the diffuse X-ray emission in a sample of 19 CGs observed with the Chandra X-Ray Observatory. Our analysis shows that the hottest, most X-ray luminous CGs agree well with the galaxy cluster X-ray scaling relations, even in CGs where the hot gas is clearly associated with the brightest galaxy. Using Spitzer photometry, we compute stellar masses and combine them with HI masses from the literature to find that high-baryonic-mass CGs are often X-ray luminous, while lower-mass CGs only sometimes exhibit faint X-ray emission attributed to star formation. We also use a new physically motivated definition of fossil groups (evolved galaxy groups where most of the mass is concentrated within a single galaxy) to investigate the hot gas properties of three compact fossil systems in our sample. In addition, we find that the most X-ray luminous CGs have the lowest star formation rates, likely because the cold gas has been exhausted in star formation, heated to X-ray temperatures, or removed from the galaxies by ram-pressure stripping. Finally, the optical colors that trace the recent star formation histories of the most massive group galaxies do not correlate with the X-ray luminosities of the CGs, indicating that perhaps the current state of the X-ray halos is not dependent on the recent assembly of stellar mass in the most massive galaxies. This work has been supported by the Natural Science and Engineering Research Council of Canada, the Ontario Early Researcher Award Program, and NASA.

  19. Compound classification by computer treatment of low resolution mass spectra - Application to geochemical and environmental problems.

    Science.gov (United States)

    Smith, D. H.; Eglinton, G.

    1972-01-01

    A description is given of a development of computer analysis of low-resolution chromatographic-mass spectrometric data, which provides a preliminary classification of an unknown spectrum as a listing of candidate classes of compounds. This procedure, referred to as COMSOC (Classification of Mass Spectra on Computers), operates by converting an incoming unknown mass spectrum into a simplified key word which is then compared with each of the key words held in its reference file. The advantages of COMSOC in characterizing complex mixtures are emphasized.

  20. String junction as a baryonic constituent

    CERN Document Server

    Kalashnikova, Yu S

    1995-01-01

    We extend the model for QCD string with quarks to consider the Mercedes Benz string configuration describing the three-quark baryon. Under the assumption of adiabatic separation of quark and string junction motion we formulate and solve the classical equation of motion for the junction.We dare to quantize the motion of the junction, and discuss the impact of these modes on the baryon spectra.

  1. Deforming baryons into confining strings

    CERN Document Server

    Hartnoll, S A; Hartnoll, Sean A.; Portugues, Ruben

    2004-01-01

    We find explicit probe D3-brane solutions in the infrared of the Maldacena-Nunez background. The solutions describe deformed baryon vertices: q external quarks are separated in spacetime from the remaining N-q. As the separation is taken to infinity we recover known solutions describing infinite confining strings in ${\\mathcal{N}}=1$ gauge theory. We present results for the mass of finite confining strings as a function of length. We also find probe D2-brane solutions in a confining type IIA geometry, the reduction of a G_2 holonomy M theory background. The interpretation of these solutions as deformed baryons/confining strings is not as straightforward.

  2. Heavy Baryons and Exotics Spectrum

    CERN Document Server

    Karliner, Marek; Tornqvist, Nils A

    2011-01-01

    We discuss several highly accurate theoretical predictions for masses of baryons containing the b quark which have been recently confirmed by experimental data. Several predictions are given for additional properties of heavy baryons. We also discuss the two charged exotic resonances Z_b with quantum numbers of a (b bbar u ddbar) tetraquark, very recently reported by Belle in the channel [Upsilon(nS) \\pi^+, n=1,2,3]. Among possible implications are deeply bound I=0 counterparts of the Z_b-s and existence of a Sigma_b^+ Sigma_b^- dibaryon, a "beauteron".

  3. Improved Peak Detection and Deconvolution of Native Electrospray Mass Spectra from Large Protein Complexes.

    Science.gov (United States)

    Lu, Jonathan; Trnka, Michael J; Roh, Soung-Hun; Robinson, Philip J J; Shiau, Carrie; Fujimori, Danica Galonic; Chiu, Wah; Burlingame, Alma L; Guan, Shenheng

    2015-12-01

    Native electrospray-ionization mass spectrometry (native MS) measures biomolecules under conditions that preserve most aspects of protein tertiary and quaternary structure, enabling direct characterization of large intact protein assemblies. However, native spectra derived from these assemblies are often partially obscured by low signal-to-noise as well as broad peak shapes because of residual solvation and adduction after the electrospray process. The wide peak widths together with the fact that sequential charge state series from highly charged ions are closely spaced means that native spectra containing multiple species often suffer from high degrees of peak overlap or else contain highly interleaved charge envelopes. This situation presents a challenge for peak detection, correct charge state and charge envelope assignment, and ultimately extraction of the relevant underlying mass values of the noncovalent assemblages being investigated. In this report, we describe a comprehensive algorithm developed for addressing peak detection, peak overlap, and charge state assignment in native mass spectra, called PeakSeeker. Overlapped peaks are detected by examination of the second derivative of the raw mass spectrum. Charge state distributions of the molecular species are determined by fitting linear combinations of charge envelopes to the overall experimental mass spectrum. This software is capable of deconvoluting heterogeneous, complex, and noisy native mass spectra of large protein assemblies as demonstrated by analysis of (1) synthetic mononucleosomes containing severely overlapping peaks, (2) an RNA polymerase II/α-amanitin complex with many closely interleaved ion signals, and (3) human TriC complex containing high levels of background noise. Graphical Abstract ᅟ. PMID:26323614

  4. Baryonic and Non-Baryonic Dark Matter

    OpenAIRE

    Carr, Bernard

    2000-01-01

    Cosmological nucleosynthesis calculations imply that there should be both non-baryonic and baryonic dark matter. Recent data suggest that some of the non-baryonic dark matter must be "hot" (i.e. massive neutrinos) and there may also be evidence for "cold" dark matter (i.e. WIMPs). If the baryonic dark matter resides in galactic halos, it is likely to be in the form of compact objects (i.e. MACHOs) and these would probably be the remnants of a first generation of pregalactic or protogalactic P...

  5. Some like it hot: Linking diffuse X-ray luminosity, baryonic mass, and star formation rate in compact groups of galaxies

    International Nuclear Information System (INIS)

    We present an analysis of the diffuse X-ray emission in 19 compact groups (CGs) of galaxies observed with Chandra. The hottest, most X-ray luminous CGs agree well with the galaxy cluster X-ray scaling relations in LX -T and LX -σ, even in CGs where the hot gas is associated with only the brightest galaxy. Using Spitzer photometry, we compute stellar masses and classify Hickson CGs 19, 22, 40, and 42, and RSCGs 32, 44, and 86 as fossil groups using a new definition for fossil systems that includes a broader range of masses. We find that CGs with total stellar and H I masses ≳ 1011.3 M☉ are often X-ray luminous, while lower-mass CGs only sometimes exhibit faint, localized X-ray emission. Additionally, we compare the diffuse X-ray luminosity against both the total UV and 24 μm star formation rates of each CG and optical colors of the most massive galaxy in each of the CGs. The most X-ray luminous CGs have the lowest star formation rates, likely because there is no cold gas available for star formation, either because the majority of the baryons in these CGs are in stars or the X-ray halo, or due to gas stripping from the galaxies in CGs with hot halos. Finally, the optical colors that trace recent star formation histories of the most massive group galaxies do not correlate with the X-ray luminosities of the CGs, indicating that perhaps the current state of the X-ray halos is independent of the recent history of stellar mass assembly in the most massive galaxies.

  6. Several Crucial Problems in Evaluating Spectra of Baryons with Two Heavy Quarks%带有两个重夸克的重子谱计算中几个困难问题的研究

    Institute of Scientific and Technical Information of China (English)

    童胜平; 丁亦兵; 郭新恒; 金宏英; 李学潜; 沈彭年; 张瑞

    2000-01-01

    The spectra of baryons which include two heavy quarks and one light quark can be treated as a two-body system,where two h eavy quarks constitute a bosonic diquark.We derive the effective potential betwe en the light quark and the heavy diquark.In this work we have discussed several serious problems:(1)the operator ordering,(2)the errors caused by the non-relati vistic expansion,(3)spin-spin coupling and (4)the mixing between baryon states w ith scalar-diquark and vector-diquark.%由两个重夸克和一个轻夸克组成的重子可以看作是一个两体系统.它的两个重夸克组成一个玻色型的双夸克团.利用B-S方程导出了它的轻夸克和重的双夸克之间的等效相互作用势.在利用这种势计算重子质量的过程中,发现有几个困难问题需要深入探讨.它们是:(1)算符排序,(2)由非相对论展开带来的误差,(3)自旋-自旋耦合,(4)在标量双夸克组成的重子态和矢量双夸克组成的重子态之间的混合.本文详细地讨论并适当地处理了这些问题.

  7. Dynamically generated baryon resonances

    CERN Document Server

    Lutz, M F M

    2005-01-01

    Identifying a zero-range exchange of vector mesons as the driving force for the s-wave scattering of pseudo-scalar mesons off the baryon ground states, a rich spectrum of molecules is formed. We argue that chiral symmetry and large-$N_c$ considerations determine that part of the interaction which generates the spectrum. We suggest the existence of strongly bound crypto-exotic baryons, which contain a charm-anti-charm pair. Such states are narrow since they can decay only via OZI-violating processes. A narrow nucleon resonance is found at mass 3.52 GeV. It is a coupled-channel bound state of the $(\\eta_c N), (\\bar D \\Sigma_c)$ system, which decays dominantly into the $(\\eta' N)$ channel. Furthermore two isospin singlet hyperon states at mass 3.23 GeV and 3.58 GeV are observed as a consequence of coupled-channel interactions of the $(\\bar D_s \\Lambda_c), (\\bar D \\Xi_c)$ and $(\\eta_c \\Lambda),(\\bar D \\Xi_c')$ states. Most striking is the small width of about 1 MeV of the lower state. The upper state may be signi...

  8. Relative mass defect filtering of mass spectra: a path to discovery of plant specialized metabolites.

    Science.gov (United States)

    Ekanayaka, E A Prabodha; Celiz, Mary Dawn; Jones, A Daniel

    2015-04-01

    The rapid identification of novel plant metabolites and assignments of newly discovered substances to natural product classes present the main bottlenecks to defining plant specialized phenotypes. Although mass spectrometry provides powerful support for metabolite discovery by measuring molecular masses, ambiguities in elemental formulas often fail to reveal the biosynthetic origins of specialized metabolites detected using liquid chromatography-mass spectrometry. A promising approach for mining liquid chromatography-mass spectrometry metabolite profiling data for specific metabolite classes is achieved by calculating relative mass defects (RMDs) from molecular and fragment ions. This strategy enabled the rapid recognition of an extensive range of terpenoid metabolites in complex plant tissue extracts and is independent of retention time, abundance, and elemental formula. Using RMD filtering and tandem mass spectrometry data analysis, 24 novel elemental formulas corresponding to glycosylated sesquiterpenoid metabolites were identified in extracts of the wild tomato Solanum habrochaites LA1777 trichomes. Extensive isomerism was revealed by ultra-high-performance liquid chromatography, leading to evidence of more than 200 distinct sesquiterpenoid metabolites. RMD filtering led to the recognition of the presence of glycosides of two unusual sesquiterpenoid cores that bear limited similarity to known sesquiterpenes in the genus Solanum. In addition, RMD filtering is readily applied to existing metabolomics databases and correctly classified the annotated terpenoid metabolites in the public metabolome database for Catharanthus roseus. PMID:25659383

  9. Baryonic matter and beyond

    CERN Document Server

    Fukushima, Kenji

    2014-01-01

    We summarize recent developments in identifying the ground state of dense baryonic matter and beyond. The topics include deconfinement from baryonic matter to quark matter, a diquark mixture, topological effect coupled with chirality and density, and inhomogeneous chiral condensates.

  10. OMA and OPA—Software-Supported Mass Spectra Analysis of Native and Modified Nucleic Acids

    Science.gov (United States)

    Nyakas, Adrien; Blum, Lorenz C.; Stucki, Silvan R.; Reymond, Jean-Louis; Schürch, Stefan

    2013-02-01

    The platform-independent software package consisting of the oligonucleotide mass assembler (OMA) and the oligonucleotide peak analyzer (OPA) was created to support the analysis of oligonucleotide mass spectra. It calculates all theoretically possible fragments of a given input sequence and annotates it to an experimental spectrum, thus, saving a large amount of manual processing time. The software performs analysis of precursor and product ion spectra of oligonucleotides and their analogues comprising user-defined modifications of the backbone, the nucleobases, or the sugar moiety, as well as adducts with metal ions or drugs. The ability to expand the library of building blocks and to implement individual structural variations makes it extremely useful for supporting the analysis of therapeutically active compounds. The functionality of the software tool is demonstrated on the examples of a platinated double-stranded oligonucleotide and a modified RNA sequence. Experiments also reveal the unique dissociation behavior of platinated higher-order DNA structures.

  11. What do Matrix-Assisted Laser Desorption/Ionization Mass Spectra Reveal about Ionization Mechanisms?

    Energy Technology Data Exchange (ETDEWEB)

    Papantonakis, Michael R.(VISITORS); Kim, Jun S.(ASSOC WESTERN UNIVERSITY); Hess, Wayne P.(BATTELLE (PACIFIC NW LAB)); Haglund, Richard F.(Vanderbilt University)

    2002-06-01

    We describe the results of experiments designed to test several of the most widely discussed mechanistic models for matrix-assisted laser desorption and ionization. By comparing ion mass spectra from the same matrix-analyte systems across various wavelengths from ultraviolet to mid-infrared and pulse durations from nanosecond to femtosecond, we have evaluated the plausibility of such ion-formation mechanisms as multiphoton ionization, excited state ionization, and photothermal ionization. We conclude that some of these models are not plausible for the matrix-analyte systems we studied. However, the fundamental principles of the laser-materials interaction also suggest that inspection of the mass spectra alone can only serve to exclude certain mechanisms, not to establish which of several competing mechanisms is actually occurring. This is particularly true with respect to variations in pulse duration and wavelength.

  12. The mass spectra, hierarchy and cosmology of B-L MSSM heterotic compactifications

    International Nuclear Information System (INIS)

    The matter spectrum of the MSSM, including three right-handed neutrino supermultiplets and one pair of Higgs-Higgs conjugate superfields, can be obtained by compactifying the E8 x E8 heterotic string and M-theory on Calabi-Yau manifolds with specific SU(4) vector bundles. These theories have the standard model gauge group augmented by an additional gauged U(1)B-L. Their minimal content requires that the B-L gauge symmetry be spontaneously broken by a vacuum expectation value of at least one right-handed neutrino. In previous papers, we presented the results of a quasi-analytic renormalization group analysis showing that B-L gauge symmetry is indeed radiatively broken with an appropriate B-L/electroweak hierarchy. In this paper, we extend these results by 1) enlarging the initial parameter space and 2) explicitly calculating all renormalization group equations numerically. The regions of the initial parameter space leading to realistic vacua are presented and the B-L/electroweak hierarchy computed over these regimes. At representative points, the mass spectrum for all particles and Higgs fields is calculated and shown to be consistent with present experimental bounds. Some fundamental phenomenological signatures of a non-zero right-handed neutrino expectation value are discussed, particularly the cosmology and proton lifetime arising from induced lepton and baryon number violating interactions

  13. A pattern recognition system for prostate mass spectra discrimination based on the CUDA parallel programming model

    International Nuclear Information System (INIS)

    The aim of the present study was to implement a pattern recognition system for the discrimination of healthy from malignant prostate tumors from proteomic Mass Spectroscopy (MS) samples and to identify m/z intervals of potential biomarkers associated with prostate cancer. One hundred and six MS-spectra were studied in total. Sixty three spectra corresponded to healthy cases (PSA < 1) and forty three spectra were cancerous (PSA > 10). The MS-spectra are publicly available from the NCI Clinical Proteomics Database. The pre-processing comprised the steps: denoising, normalization, peak extraction and peak alignment. Due to the enormous number of features that rose from MS-spectra as informative peaks, and in order to secure optimum system design, the classification task was performed by programming in parallel the multiprocessors of an nVIDIA GPU card, using the CUDA framework. The proposed system achieved 98.1% accuracy. The identified m/z intervals displayed significant statistical differences between the two classes and were found to possess adequate discriminatory power in characterizing prostate samples, when employed in the design of the classification system. Those intervals should be further investigated since they might lead to the identification of potential new biomarkers for prostate cancer

  14. Simulation of experimental spectra for medium-heavy nuclides in accelerator mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    WANG Hui-Juan; GUAN Yong-Jing; HE Ming; RUAN Xiang-Dong; DONG Ke-Jun; LI Guo-Qiang; Wu Shao-Yong; WU Wei-Ming; JIANG Shan

    2005-01-01

    Some interferences are often encountered in accelerator mass spectrometry (AMS) measurements, especially for medium-heavy nuclide measurement. It is difficult for online discrimination of the nuclide of interest from the interfering ones. In order to solve this problem, we developed a method to simulate the experimental spectra of medium-heavy nuclides in AMS measurements. The results obtained from this method are in good agreement with experimental values.

  15. De novo analysis of electron impact mass spectra using fragmentation trees

    Energy Technology Data Exchange (ETDEWEB)

    Hufsky, Franziska, E-mail: franziska.hufsky@uni-jena.de [Chair of Bioinformatics, Friedrich Schiller University, Ernst-Abbe-Platz 2, Jena (Germany); Max Planck Institute for Chemical Ecology, Beutenberg Campus, Jena (Germany); Rempt, Martin [Institute for Inorganic and Analytical Chemistry, Bioorganic Analytics, Friedrich Schiller University, Lessingstrasse 8, Jena (Germany); Rasche, Florian [Chair of Bioinformatics, Friedrich Schiller University, Ernst-Abbe-Platz 2, Jena (Germany); Pohnert, Georg [Institute for Inorganic and Analytical Chemistry, Bioorganic Analytics, Friedrich Schiller University, Lessingstrasse 8, Jena (Germany); Boecker, Sebastian, E-mail: sebastian.boecker@uni-jena.de [Chair of Bioinformatics, Friedrich Schiller University, Ernst-Abbe-Platz 2, Jena (Germany)

    2012-08-20

    Highlights: Black-Right-Pointing-Pointer We present a method for de novo analysis of accurate mass EI mass spectra of small molecules. Black-Right-Pointing-Pointer This method identifies the molecular ion and thus the molecular formula where the molecular ion is present in the spectrum. Black-Right-Pointing-Pointer Fragmentation trees are constructed by automated signal extraction and evaluation. Black-Right-Pointing-Pointer These trees explain relevant fragmentation reactions. Black-Right-Pointing-Pointer This method will be very helpful in the automated analysis of unknown metabolites. - Abstract: The automated fragmentation analysis of high resolution EI mass spectra based on a fragmentation tree algorithm is introduced. Fragmentation trees are constructed from EI spectra by automated signal extraction and evaluation. These trees explain relevant fragmentation reactions and assign molecular formulas to fragments. The method enables the identification of the molecular ion and the molecular formula of a metabolite if the molecular ion is present in the spectrum. These identifications are independent of existing library knowledge and, thus, support assignment and structural elucidation of unknown compounds. The method works even if the molecular ion is of very low abundance or hidden under contaminants with higher masses. We apply the algorithm to a selection of 50 derivatized and underivatized metabolites and demonstrate that in 78% of cases the molecular ion can be correctly assigned. The automatically constructed fragmentation trees correspond very well to published mechanisms and allow the assignment of specific relevant fragments and fragmentation pathways even in the most complex EI-spectra in our dataset. This method will be very helpful in the automated analysis of metabolites that are not included in common libraries and it thus has the potential to support the explorative character of metabolomics studies.

  16. Mercury clusters: Jellium-like mass spectra and threshold laws for electron impact ionisation

    International Nuclear Information System (INIS)

    Mercury clusters have been ionised by impact of electrons of variable kinetic energy. For cluster sizes n≤540 a linear threshold law is observed, which allows an accurate identification of the ionisation energies. The differences to photo ionisation are discussed. Jellium like intensity variations are observed in the mass spectra, in a size region where the bonding in Hg clusters has not yet become metallic. (orig.)

  17. De novo analysis of electron impact mass spectra using fragmentation trees

    International Nuclear Information System (INIS)

    Highlights: ► We present a method for de novo analysis of accurate mass EI mass spectra of small molecules. ► This method identifies the molecular ion and thus the molecular formula where the molecular ion is present in the spectrum. ► Fragmentation trees are constructed by automated signal extraction and evaluation. ► These trees explain relevant fragmentation reactions. ► This method will be very helpful in the automated analysis of unknown metabolites. - Abstract: The automated fragmentation analysis of high resolution EI mass spectra based on a fragmentation tree algorithm is introduced. Fragmentation trees are constructed from EI spectra by automated signal extraction and evaluation. These trees explain relevant fragmentation reactions and assign molecular formulas to fragments. The method enables the identification of the molecular ion and the molecular formula of a metabolite if the molecular ion is present in the spectrum. These identifications are independent of existing library knowledge and, thus, support assignment and structural elucidation of unknown compounds. The method works even if the molecular ion is of very low abundance or hidden under contaminants with higher masses. We apply the algorithm to a selection of 50 derivatized and underivatized metabolites and demonstrate that in 78% of cases the molecular ion can be correctly assigned. The automatically constructed fragmentation trees correspond very well to published mechanisms and allow the assignment of specific relevant fragments and fragmentation pathways even in the most complex EI-spectra in our dataset. This method will be very helpful in the automated analysis of metabolites that are not included in common libraries and it thus has the potential to support the explorative character of metabolomics studies.

  18. mMass as a Software Tool for the Annotation of Cyclic Peptide Tandem Mass Spectra

    Czech Academy of Sciences Publication Activity Database

    Niedermeyer, T. H. J.; Strohalm, Martin

    2012-01-01

    Roč. 7, č. 9 (2012), e44913. E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) ME10013 Institutional research plan: CEZ:AV0Z50200510 Keywords : cyclic peptides * nMass Subject RIV: CE - Biochemistry Impact factor: 3.730, year: 2012

  19. The Turn Over of the Odd-even Pattern in Mass Spectra of Carbon Cluster Anions

    Institute of Scientific and Technical Information of China (English)

    NI Guoquan; LIU Bingchen; ZHAI Huajin

    2000-01-01

    @@ Although investigations by many authorsd on the properties of carbon cluster anions by mass spectrometry and photoelectron spectroscopy last more than a decade[1~3], a general conclusion concerning the various features of the carbon clusters generated most commonly in laser vaporization/molecular beam sources has not yet been reached. In this Letter we report that the turn-over of the odd-even patter in relative abundance in the mass spectra of carbon clusters and the "manipulation" of the pattern can be realized in a controlled way by altering the vaporizing laser intensity, the backing pressure and the conductance of carries gas.

  20. The Higgs boson mass and SUSY spectra in 10D SYM theory with magnetized extra dimensions

    Directory of Open Access Journals (Sweden)

    Hiroyuki Abe

    2014-11-01

    Full Text Available We study the Higgs boson mass and the spectrum of supersymmetric (SUSY particles in the well-motivated particle physics model derived from a ten-dimensional supersymmetric Yang–Mills theory compactified on three factorizable tori with magnetic fluxes. This model was proposed in a previous work, where the flavor structures of the standard model including the realistic Yukawa hierarchies are obtained from non-hierarchical input parameters on the magnetized background. Assuming moduli- and anomaly-mediated contributions dominate the soft SUSY breaking terms, we study the precise SUSY spectra and analyze the Higgs boson mass in this mode, which are compared with the latest experimental data.

  1. Measuring nickel masses in Type Ia supernovae using cobalt emission in nebular phase spectra

    CERN Document Server

    Childress, Michael J; Seitenzahl, Ivo; Sullivan, Mark; Maguire, Kate; Taubenberger, Stefan; Scalzo, Richard; Ruiter, Ashley; Blagorodnova, Nadejda; Camacho, Yssavo; Castillo, Jayden; Elias-Rosa, Nancy; Fraser, Morgan; Gal-Yam, Avishay; Graham, Melissa; Howell, D Andrew; Inserra, Cosimo; Jha, Saurabh W; Kumar, Sahana; Mazzali, Paolo A; McCully, Curtis; Morales-Garoffolo, Antonia; Pandya, Viraj; Polshaw, Joe; Schmidt, Brian; Smartt, Stephen; Smith, Ken W; Sollerman, Jesper; Spyromilio, Jason; Tucker, Brad; Valenti, Stefano; Walton, Nicholas; Wolf, Christian; Yaron, Ofer; Young, D R; Yuan, Fang; Zhang, Bonnie

    2015-01-01

    The light curves of Type Ia supernovae (SNe Ia) are powered by the radioactive decay of $^{56}$Ni to $^{56}$Co at early times, and the decay of $^{56}$Co to $^{56}$Fe from ~60 days after explosion. We examine the evolution of the [Co III] 5892 A emission complex during the nebular phase for SNe Ia with multiple nebular spectra and show that the line flux follows the square of the mass of $^{56}$Co as a function of time. This result indicates both efficient local energy deposition from positrons produced in $^{56}$Co decay, and long-term stability of the ionization state of the nebula. We compile 77 nebular spectra of 25 SN Ia from the literature and present 17 new nebular spectra of 7 SNe Ia, including SN2014J. From these we measure the flux in the [Co III] 5892 A line and remove its well-behaved time dependence to infer the initial mass of $^{56}$Ni ($M_{Ni}$) produced in the explosion. We then examine $^{56}$Ni yields for different SN Ia ejected masses ($M_{ej}$ - calculated using the relation between light...

  2. Precombination Cloud Collapse and Baryonic Dark Matter

    Science.gov (United States)

    Hogan, Craig J.

    1993-01-01

    A simple spherical model of dense baryon clouds in the hot big bang 'strongly nonlinear primordial isocurvature baryon fluctuations' is reviewed and used to describe the dependence of cloud behavior on the model parameters, baryon mass, and initial over-density. Gravitational collapse of clouds before and during recombination is considered including radiation diffusion and trapping, remnant type and mass, and effects on linear large-scale fluctuation modes. Sufficiently dense clouds collapse early into black holes with a minimum mass of approx. 1 solar mass, which behave dynamically like collisionless cold dark matter. Clouds below a critical over-density, however, delay collapse until recombination, remaining until then dynamically coupled to the radiation like ordinary diffuse baryons, and possibly producing remnants of other kinds and lower mass. The mean density in either type of baryonic remnant is unconstrained by observed element abundances. However, mixed or unmixed spatial variations in abundance may survive in the diffuse baryon and produce observable departures from standard predictions.

  3. LHCb: Measurement of the $\\Lambda_b^0$, $\\Xi_b^-$ and $\\Omega_b^-$ baryon masses

    CERN Multimedia

    Märki, R

    2013-01-01

    Mass measurements of $\\Lambda_b^0$, $\\Xi_b^-$ and $\\Omega_b^-$ at LHCb using 1~fb$^{-1}$ of data collected in 2011, reconstructing $\\Lambda_b^0 \\rightarrow J/\\psi \\Lambda$, $\\Xi_b^- \\rightarrow J/\\psi \\Xi^-$ and $\\Omega_b^- \\rightarrow J/\\psi \\Omega^-$.

  4. Evolution of organic aerosol mass spectra upon heating: implications for OA phase and partitioning behavior

    Energy Technology Data Exchange (ETDEWEB)

    UC Davis; Cappa, Christopher D.; Wilson, Kevin R.

    2010-10-28

    Vacuum Ultraviolet (VUV) photoionization mass spectrometry has been used to measure the evolution of chemical composition for two distinct organic aerosol types as they are passed through a thermodenuder at different temperatures. The two organic aerosol types considered are primary lubricating oil (LO) aerosol and secondary aerosol from the alpha-pinene + O3 reaction (alphaP). The evolution of the VUV mass spectra for the two aerosol types with temperature are observed to differ dramatically. For LO particles, the spectra exhibit distinct changes with temperature in which the lower m/z peaks, corresponding to compounds with higher vapor pressures, disappear more rapidly than the high m/z peaks. In contrast, the alphaP aerosol spectrum is essentially unchanged by temperature even though the particles experience significant mass loss due to evaporation. The variations in the LO spectra are found to be quantitatively in agreement with expectations from absorptive partitioning theory whereas the alphaP spectra suggest that the evaporation of alphaP derived aerosol appears to not be governed by partitioning theory. We postulate that this difference arises from the alphaP particles existing as in a glassy state instead of having the expected liquid-like behavior. To reconcile these observations with decades of aerosol growth measurements, which indicate that OA formation is described by equilibrium partitioning, we present a conceptual model wherein the secondary OA is formed and then rapidly converted from an absorbing form to a non-absorbing form. The results suggest that although OA growth may be describable by equilibrium partitioning theory, the properties of organic aerosol once formed may differ significantly from the properties determined in the equilibrium framework.

  5. Evolution of organic aerosol mass spectra upon heating: implications for OA phase and partitioning behavior

    Science.gov (United States)

    Cappa, C. D.; Wilson, K. R.

    2011-03-01

    Vacuum Ultraviolet (VUV) photoionization mass spectrometry has been used to measure the evolution of chemical composition for two distinct organic aerosol types as they are passed through a thermodenuder at different temperatures. The two organic aerosol types considered are primary lubricating oil (LO) aerosol and secondary aerosol from the α-pinene + O3 reaction (αP). The evolution of the VUV mass spectra for the two aerosol types with temperature are observed to differ dramatically. For LO particles, the spectra exhibit distinct changes with temperature in which the lower m/z peaks, corresponding to compounds with higher vapor pressures, disappear more rapidly than the high m/z peaks. In contrast, the αP aerosol spectrum is essentially unchanged by temperature even though the particles experience significant mass loss due to evaporation. The variations in the LO spectra are found to be quantitatively in agreement with expectations from absorptive partitioning theory whereas the αP spectra suggest that the evaporation of αP derived aerosol appears to not be governed by partitioning theory. We postulate that this difference arises from diffusivity within the αP particles being sufficiently slow that they do not exhibit the expected liquid-like behavior and perhaps exist in a glassy state. To reconcile these observations with decades of aerosol growth measurements, which indicate that OA formation is described by equilibrium partitioning, we present a conceptual model wherein the secondary OA is formed and then rapidly converted from an absorbing form to a non-absorbing form. The results suggest that, although OA growth may be describable by equilibrium partitioning theory, the properties of organic aerosol once formed may differ significantly from the properties determined in the equilibrium framework.

  6. Clustering, Anisotropy, Spectra of Ultra High Energy Cosmic Ray: Finger-prints of Relic Neutrinos Masses in Dark Halos

    OpenAIRE

    Fargion, Daniele; Grossi, Marco; Lucentini, P. G. De Sanctis; Di Troia, C

    2001-01-01

    The Ultra High Energy Cosmic Ray UHECR, by UHE neutrino-relic neutrino Z showering in Hot Dark Halos HDM, should exhibits an energy spectra and an anisotropy reflecting (also) the relic neutrino masses and their hierarchical HDM halo clustering. A twin light neutrino mass splitting may reflect to twin Z resonance and into a complex UHECR spectra modulation, a twin bump, at the edge at highest GZK energy cut-off. Each possible neutrino mass associates a characteristic dark halo size (galactic,...

  7. Synthesis and Electrospray Ionization Mass Spectra of N-(1,3,2-Dioxaphosphorinan-2-ylmethyl)thiophosphoramidates

    Institute of Scientific and Technical Information of China (English)

    MIAO,Zhi-Wei; FU,Cui-Rong; WANG,Bin; CUI,Zhan-Wei; ZHANG,Jian-Feng; CHEN,Ru-Yu

    2007-01-01

    N-(1,3,2-Dioxaphosphorinan-2-ylmethyl) thiophosphoramidates were synthesized and determined by NMR spectra and positive ion electrospray ionization mass spectrometry (ESI-MS) in conjunction with tandem mass spectrometry (MS/MS). The fragmentation pathways were investigated. The results show that these characteristic ions in ESI mass spectra are useful in the structural determination of N-(1,3,2-dioxaphosphorinan-2-ylmethyl)thiophosphoramidates.

  8. Simultaneous Factor Analysis of Coupled Aerosol and VOC Mass Spectra in Regions of Biogenic Influence

    Science.gov (United States)

    Slowik, Jay; Chang, Rachel; Hayden, Katherine; Li, Shao-Meng; Liggio, John; Sjostedt, Steven; Vlasenko, Alexander; Leaitch, Richard; Abbatt, Jonathan

    2010-05-01

    Recent studies suggest that the traditional binary treatments of atmospheric organics as either gases or particles may be inadequate, highlighting the need for analytical techniques capable of simultaneously considering particle and gas-phase species. Organic mass spectra of particles and volatile organic compounds (VOCs) were collected using an Aerodyne time-of-flight aerosol mass spectrometer (C-ToF-AMS), and a proton transfer reaction-mass spectrometer (PTR-MS), respectively. The particle and VOC mass spectra were combined into a single dataset, which was analyzed using the positive matrix factorization (PMF) receptor modeling technique. The relative weights of the AMS and PTR-MS data were balanced in the PMF analysis according to the criteria that the scaled residuals within a solution be independent of the measuring instrument. Instrument relative weight is controlled by the application of a scaling factor to the PTR-MS uncertainties. The AMS and PTR-MS instruments were deployed from mid-May to mid-June at two sites in Canada: (1) Egbert, ON (2007), a semirural site ~70 km north of Toronto, and (2) Whistler, BC (2008), a remote site ~120 km north of Vancouver. The Egbert site is influenced by anthropogenic emissions from Toronto and populated regions to the south, biogenic emissions from boreal forests to the north, and biomass burning emissions. The Whistler site is strongly influenced by boreal forest terpene emissions, with lesser contributions from long-range transport and anthropogenic emissions.

  9. Beautiful Baryons from Lattice QCD

    OpenAIRE

    Alexandrou, C.; Borrelli, A; Güsken, S.; Jegerlehner, F.; K. Schilling; Siegert, G.; Sommer, R

    1994-01-01

    We perform a lattice study of heavy baryons, containing one ($\\Lambda_b$) or two $b$-quarks ($\\Xi_b$). Using the quenched approximation we obtain for the mass of $\\Lambda_b$ $$ M_{\\Lambda_b}= 5.728 \\pm 0.144 \\pm 0.018 {\\rm GeV}.$$ The mass splitting between the $\\Lambda_b$ and the B-meson is found to increase by about 20\\% if the light quark mass is varied from the chiral limit to the strange quark mass.

  10. Diquark model of the baryon spectrum

    International Nuclear Information System (INIS)

    The presence of a coherent diquark structure within baryons has been suggested, both as a computational tool for simplifying some types of baryon calculations, and as an explanation for scaling violations in deep inelastic scattering. In this paper we consider the implications of the diquark hypothesis for baryons spectroscopy. Treating the diquark as an s-wave bound state of two quarks reduces the problem of three-body quark excitations within baryons to that of a two-body quark-diquark interaction. The spin-dependent excitation levels of the quark-diquark system can then be calculated in perturbative QCD, using a non-relativistic one-gluon-exchange approximation. The spectrum generated by this model differs from the conventional symmetric quark model spectrum in several crucial respects. Firstly, spin-orbit mass splitting between baryons is easily accommodated in the diquark picture, unlike the conventional model, where it must be cancelled ad hoc in order to obtain a reasonable fit to the mass spectrum. Secondly, the QCD parameters needed to fit the baryon spectrum in the diquark model are essentially the same as those used in the meson spectrum. This allows us to give a unified description of spin-dependent forces in mesons and baryons, which has not been possible in the symmetric quark model. We conclude with a qualitative discussion of spin-independent (multiple gluon exchange) forces in the diquark model, using effective confining potentials of the form, V(r) approx. r/sup n/. 28 references

  11. Mass and Hot Baryons in Massive Galaxy Clusters from Subaru Weak Lensing and AMiBA SZE Observations

    CERN Document Server

    Umetsu, K; Liu, G -C; Wu, J -H P; Medezinski, E; Broadhurst, T; Lemze, D; Zitrin, A; Ho, P T P; Huang, C -W L; Koch, P M; Liao, Y -W; Lin, K -Y; Molnár, S M; Nishioka, H; Wang, F -C; Altamirano, P; Chang, C -H; Chang, S -H; Chang, S -W; Chen, M -T; Han, C -C; Huang, Y -D; Hwang, Y -J; Jiang, H; Kesteven, M; Kubo, D Y; Li, C -T; Martin-Cocher, P; Oshiro, P; Raffin, P; Wei, T; Wilson, W

    2008-01-01

    We present a multiwavelength analysis of a sample of four hot (T_X>8keV) X-ray galaxy clusters (A1689, A2261, A2142, and A2390) using joint AMiBA Sunyaev-Zel'dovich effect (SZE) and Subaru weak lensing observations, combined with published X-ray temperatures, to examine the distribution of mass and the intracluster medium (ICM) in massive cluster environments. Our observations establish that A2261 is very similar to A1689 in terms of both weak and strong lensing properties. Many tangential arcs are visible around A2261, with an effective Einstein radius \\sim 40 arcsec (at z \\sim 1.5), which when combined with our weak lensing measurements implies a mass profile well fitted by an NFW model with a high concentration c_{vir} \\sim 10, similar to A1689 and to other massive clusters. The cluster A2142 shows complex mass substructure, and displays a shallower profile (c_{vir} \\sim 5), being well traced by the SZE in the AMiBA map, and consistent with detailed X-ray observations which imply recent interaction. For A2...

  12. De novo sequencing of peptides from top-down tandem mass spectra

    Energy Technology Data Exchange (ETDEWEB)

    Vyatkina, Kira; Wu, Si; Dekker, Leendert J.; vanDuijn, Martijn M.; Liu, Xiaowen; Tolic, Nikola; Dvorkin, Mikhail; Alexandrova, Sonya; Luider, Theo N.; Pasa-Tolic, Ljiljana; Pevzner, Pavel A.

    2015-09-28

    De novo sequencing of proteins and peptides is one of the most important problems in mass spectrometry-driven proteomics. A variety of methods have been developed to accomplish this task from a set of bottom-up tandem (MS/MS) mass spectra. However, a more recently emerged top-down technology, now gaining more and more popularity, opens new perspectives for protein analysis and characterization, implying a need in efficient algorithms for processing this kind of MS/MS data. Here we describe a method that allows to retrieve from a set of top-down MS/MS spectra long and accurate sequence fragments of the proteins contained in a sample. To this end, we outline a strategy for generating high-quality sequence tags from top-down spectra, and introduce the concept of a T-Bruijn graph by adapting to the case of tags the notion of an A-Bruijn graph widely used in genomics. The output of the proposed approach represents the set of amino acid strings spelled out by optimal paths in the connected components of a T-Bruijn graph. We illustrate its performance on top-down datasets acquired from carbonic anhydrase 2 (CAH2) and the Fab region of alemtuzumab.

  13. Automated reduction and interpretation of multidimensional mass spectra for analysis of complex peptide mixtures

    Science.gov (United States)

    Gambin, Anna; Dutkowski, Janusz; Karczmarski, Jakub; Kluge, Boguslaw; Kowalczyk, Krzysztof; Ostrowski, Jerzy; Poznanski, Jaroslaw; Tiuryn, Jerzy; Bakun, Magda; Dadlez, Michal

    2007-01-01

    Here we develop a fully automated procedure for the analysis of liquid chromatography-mass spectrometry (LC-MS) datasets collected during the analysis of complex peptide mixtures. We present the underlying algorithm and outcomes of several experiments justifying its applicability. The novelty of our approach is to exploit the multidimensional character of the datasets. It is common knowledge that highly complex peptide mixtures can be analyzed by liquid chromatography coupled with mass spectrometry, but we are not aware of any existing automated MS spectra interpretation procedure designed to take into account the multidimensional character of the data. Our work fills this gap by providing an effective algorithm for this task, allowing for automated conversion of raw data to the list of masses of peptides.

  14. Automated methods for quantitative and qualitative analysis of PTR-TOF mass spectra

    International Nuclear Information System (INIS)

    Statistical analysis of measured signals from counting systems is a common method to increase the accuracy and precision of peak position and peak area. The most common approach to analyze data gained from counting systems is to fit the data peak by peak using an appropriate probability density function (PDF) like a Gaussian function. Since a counting system creates histograms, the counted data do not represent data points of the anticipated PDF. Therefore, one should not fit any PDF directly to the histogram data. Here we present a solution to this problem by fitting distributions instead of densities. A simple formula allows to correct for Poisson statistics and dead-time effects. The improved peak analysis method is applied to mass spectra obtained from a recently developed proton-transfer-reaction time-offlight mass spectrometer (PTR-TOF) enhancing the mass accuracy and peak quantification. (author)

  15. Correlated ion analysis and the interpretation of atom probe mass spectra

    International Nuclear Information System (INIS)

    Several techniques are presented for extracting information from atom probe mass spectra by investigating correlations within multiple-ion detector events. Analyses of this kind can provide insights into the origins of noise, the shape of mass peaks, or unexpected anomalies within the spectrum. Data can often be recovered from within the spectrum noise by considering the time-of-flight differences between ions within a multiple event. Correlated ion detection, particularly when associated with shifts in ion energies, may be used to probe the phenomenon of molecular ion dissociation, including the questions of data loss due to ion pile-up or the generation of neutrals in the dissociation process. -- Research Highlights: → Multiple-ion detection events may contain information not seen in the mass spectrum. → Analysis of multiple events can yield information on molecular ion dissociation. → Neutral species may be generated by dissociation subsequent to field evaporation.

  16. Mass and Hot Baryons in Massive Galaxy Clusters from Subaru Weak Lensing and AMiBA SZE Observations

    OpenAIRE

    Umetsu, Keiichi; Birkinshaw, Mark; Liu, Guo-Chin; Wu, Jiun-Huei Proty; Medezinski, Elinor; Broadhurst, Tom; Lemze, Doron; Zitrin, Adi; Ho, Paul T. P.; Huang, Chih-Wei Locutus; Koch, Patrick M.; Liao, Yu-Wei; Lin, Kai-Yang; Molnar, Sandor M.; Nishioka, Hiroaki

    2008-01-01

    We present a multiwavelength analysis of a sample of four hot (T_X>8keV) X-ray galaxy clusters (A1689, A2261, A2142, and A2390) using joint AMiBA Sunyaev-Zel'dovich effect (SZE) and Subaru weak lensing observations, combined with published X-ray temperatures, to examine the distribution of mass and the intracluster medium (ICM) in massive cluster environments. Our observations show that A2261 is very similar to A1689 in terms of lensing properties. Many tangential arcs are visible around A226...

  17. In silico fragmentation for computer assisted identification of metabolite mass spectra

    Directory of Open Access Journals (Sweden)

    Müller-Hannemann Matthias

    2010-03-01

    Full Text Available Abstract Background Mass spectrometry has become the analytical method of choice in metabolomics research. The identification of unknown compounds is the main bottleneck. In addition to the precursor mass, tandem MS spectra carry informative fragment peaks, but the coverage of spectral libraries of measured reference compounds are far from covering the complete chemical space. Compound libraries such as PubChem or KEGG describe a larger number of compounds, which can be used to compare their in silico fragmentation with spectra of unknown metabolites. Results We created the MetFrag suite to obtain a candidate list from compound libraries based on the precursor mass, subsequently ranked by the agreement between measured and in silico fragments. In the evaluation MetFrag was able to rank most of the correct compounds within the top 3 candidates returned by an exact mass query in KEGG. Compared to a previously published study, MetFrag obtained better results than the commercial MassFrontier software. Especially for large compound libraries, the candidates with a good score show a high structural similarity or just different stereochemistry, a subsequent clustering based on chemical distances reduces this redundancy. The in silico fragmentation requires less than a second to process a molecule, and MetFrag performs a search in KEGG or PubChem on average within 30 to 300 seconds, respectively, on an average desktop PC. Conclusions We presented a method that is able to identify small molecules from tandem MS measurements, even without spectral reference data or a large set of fragmentation rules. With today's massive general purpose compound libraries we obtain dozens of very similar candidates, which still allows a confident estimate of the correct compound class. Our tool MetFrag improves the identification of unknown substances from tandem MS spectra and delivers better results than comparable commercial software. MetFrag is available through a web

  18. Cosmic Ray Energy Spectra and Mass Composition at the Knee - Recent Results from KASCADE -

    CERN Document Server

    Kampert, K H; Apel, W D; Badea, F; Bekk, K; Bercuci, A; Blümer, H; Bozdog, H; Brancus, I M; Büttner, C; Chilingarian, A A; Daumiller, K; Doll, P; Engel, R; Engler, J; Fessler, F; Gils, H J; Glasstetter, R; Haungs, A; Heck, D; Hörandel, J R; Klages, H O; Maier, G; Mathes, H J; Mayer, H J; Milke, J; Müller, M; Obenland, R; Oehlschläger, J; Ostapchenko, S; Petcu, M; Plewnia, S; Rebel, H; Risse, A; Risse, M; Roth, M; Schatz, G; Schieler, H; Scholz, J; Stumpert, M; Thouw, T; Ulrich, H; Van Buren, J; Vardanyan, A; Weindl, A; Wochele, J; Zabierowski, J; Zagromski, S

    2004-01-01

    Recent results from the KASCADE experiment on measurements of cosmic rays in the energy range of the knee are presented. Emphasis is placed on energy spectra of individual mass groups as obtained from an two-dimensional unfolding applied to the reconstructed electron and truncated muon numbers of each individual EAS. The data show a knee-like structure in the energy spectra of light primaries (p, He, C) and an increasing dominance of heavy ones (A > 20) towards higher energies. This basic result is robust against uncertainties of the applied interaction models QGSJET and SIBYLL which are used in the shower simulations to analyse the data. Slight differences observed between experimental data and EAS simulations provide important clues for further improvements of the interaction models. The data are complemented by new limits on global anisotropies in the arrival directions of CRs and by upper limits on point sources. Astrophysical implications for discriminating models of maximum acceleration energy vs galact...

  19. Evolving mass spectra of the oxidized component of organic aerosol: results from aerosol mass spectrometer analyses of aged diesel emissions

    Directory of Open Access Journals (Sweden)

    A. M. Sage

    2007-07-01

    Full Text Available The species and chemistry responsible for secondary organic aerosol (SOA formation remain highly uncertain. Laboratory studies of the oxidation of individual, high-flux SOA precursors do not lead to particles with mass spectra (MS matching those of ambient aged organic material. And, the complexity of real organic particles challenges efforts to identify their chemical origins. We have previously hypothesized that SOA can form from the atmospheric oxidation of a large suite of precursors with varying vapor pressures. Here, we support this hypothesis by using an aerosol mass spectrometer to track the chemical evolution of diesel exhaust as it is photochemically oxidized in an environmental chamber. With explicit knowledge of the condensed-phase MS of the primary emissions from our engine, we are able to decompose each recorded MS into contributing primary and secondary spectra throughout the experiment. We find that the SOA MS becomes increasingly oxidized as a function of time, eventually reaching a final MS that closely resembles that of ambient aged organic particulate matter. This observation is consistent with the idea that lower vapor pressure, semi-volatile organic emissions can form condensable products with fewer generations of oxidation, and therefore, they form relatively less oxidized SOA very quickly.

  20. Effects of critical collapse on primordial black-hole mass spectra

    Energy Technology Data Exchange (ETDEWEB)

    Kuehnel, Florian [Stockholm University, AlbaNova, Department of Physics, The Oskar Klein Centre for Cosmoparticle Physics, Stockholm (Sweden); Rampf, Cornelius [University of Portsmouth, Institute of Cosmology and Gravitation, Portsmouth (United Kingdom); Sandstad, Marit [Stockholm University, Nordita, KTH Royal Institute of Technology, Stockholm (Sweden)

    2016-02-15

    Certain inflationary models as well as realisations of phase transitions in the early Universe predict the formation of primordial black holes. For most mass ranges, the fraction of matter in the form of primordial black holes is limited by many different observations on various scales. Primordial black holes are assumed to be formed when overdensities that cross the horizon have Schwarzschild radii larger than the horizon. Traditionally it was therefore assumed that primordial black-hole masses were equal to the horizon mass at their time of formation. However, detailed calculations of their collapse show that primordial black holes formed at each point in time should rather form a spectrum of different masses, obeying critical scaling. Though this has been known for more than 15 years, the effect of this scaling behaviour is largely ignored when considering predictions for primordial black-hole mass spectra. In this paper we consider the critical collapse scaling for a variety of models which produce primordial black holes, and find that it generally leads to a shift, broadening and an overall decrease of the mass contained in primordial black holes. This effect is model and parameter dependent and cannot be contained by a constant rescaling of the spectrum; it can become important and should be taken into account when comparing to observational constraints. (orig.)

  1. Effects of critical collapse on primordial black-hole mass spectra

    International Nuclear Information System (INIS)

    Certain inflationary models as well as realisations of phase transitions in the early Universe predict the formation of primordial black holes. For most mass ranges, the fraction of matter in the form of primordial black holes is limited by many different observations on various scales. Primordial black holes are assumed to be formed when overdensities that cross the horizon have Schwarzschild radii larger than the horizon. Traditionally it was therefore assumed that primordial black-hole masses were equal to the horizon mass at their time of formation. However, detailed calculations of their collapse show that primordial black holes formed at each point in time should rather form a spectrum of different masses, obeying critical scaling. Though this has been known for more than 15 years, the effect of this scaling behaviour is largely ignored when considering predictions for primordial black-hole mass spectra. In this paper we consider the critical collapse scaling for a variety of models which produce primordial black holes, and find that it generally leads to a shift, broadening and an overall decrease of the mass contained in primordial black holes. This effect is model and parameter dependent and cannot be contained by a constant rescaling of the spectrum; it can become important and should be taken into account when comparing to observational constraints. (orig.)

  2. Database-independent, database-dependent, and extended interpretation of peptide mass spectra in VEMS V2.0

    DEFF Research Database (Denmark)

    Matthiesen, Rune; Bunkenborg, Jakob; Stensballe, Allan;

    2004-01-01

    The Virtual Expert Mass Spectrometrist (VEMS) program package was developed for flexible, automated, and manual de novo tandem mass spectrometry (MS/MS) protein sequencing, and includes accessory programs for matrix-assisted laser desorption/ionization-mass spectrometry (MS) interpretation, and...... analysis of the fragmentation spectra obtained by liquid chromatrography-MS/MS analysis of peptides from an anionic peroxidase enriched protein fraction from potato root tissue. The extended analysis mode resulted in the additional assignment of spectra for nine modified tryptic peptides and nine...... miscleaved peptides, in addition to the 45 spectra from regular tryptic peptides. Of the nine modified peptides, three were glycosylated....

  3. Study of multi-photon ionization mass spectra of triethylamine at the laser of 266 nm

    International Nuclear Information System (INIS)

    Using the four-harmonic YAG laser as excitation source, studying on the process of resonance-enhanced two-photon ionization of triethylamine, the time-of-flight mass spectra of triethylamine is obtained. Parent ion and fragment ion reach as much as 29 kinds. Analyzing the abnormal variation of (C2H5)2N+ CH2(86+) show that when the signal ions' intensity are very strong, the 25-times instantaneous deceleration effort of 25 kinds of ions before 86+ are stronger than 3-times deceleration effort of 3 kinds of ions after 86+. (authors)

  4. Authentication of Fish Products by Large-Scale Comparison of Tandem Mass Spectra

    DEFF Research Database (Denmark)

    Wulff, Tune; Nielsen, Michael Engelbrecht; Deelder, André M.;

    2013-01-01

    workflow including protein extraction, digestion, and data analysis. First, a set of reference spectral libraries was generated using unprocessed muscle tissue from 22 different fish species. Query tandem mass spectrometry data sets from “unknown” fresh muscle tissue samples were then searched against...... the reference libraries. The number of matching spectra could unambiguously identify the origin of all fresh samples. A number of processed samples were also analyzed to further test the robustness and applicability of the method. The results clearly show that the method is also able to correctly identify...

  5. Baryons and Mesons with Beauty

    OpenAIRE

    Goldstein, Gary R.; Wali, Kameshwar C.

    2007-01-01

    Recent experimental findings of several mesons and baryons with "beauty" and "charm" as flavors remind us of the days when strangeness was discovered, and how its inclusion led to SU(3)-flavor symmetry with enormous success in the classification of the "proliferated" states into SU(3) multiplets. One of the key elements was the successful application of the first order perturbation in symmetry breaking, albeit what then appeared to be huge mass differences, and the prediction of new states th...

  6. Spectroscopy of singly, doubly, and triply bottom baryons

    CERN Document Server

    Wei, Ke-Wei; Liu, Na; Wang, Qian-Qian; Guo, Xin-Heng

    2016-01-01

    Recently, many singly bottom baryons have been established experimentally, but no doubly or triply bottom baryon has been observed. Under the Regge phenomenology, the mass of a ground state unobserved doubly or triply bottom baryon is expressed as a function of masses of the well established light baryons and singly bottom baryons. (For example, we write the mass of $\\Omega_{bbb}$ as a function of the masses of well established light baryons ($\\Sigma^{*}$, $\\Xi^{*}$, $\\Omega$) and singly bottom baryons ($\\Sigma_b^{*}$, $\\Xi_b^{*}$), and give its value to be 14788$\\pm$80 MeV.) After that, we calculate the values of Regge slopes and Regge intercepts for singly, doubly, and triply bottom baryons. (Regge intercepts and slopes, which are usually regarded as fundamental constants of hadron dynamics, are useful for many spectral and nonspectral purposes.) Then, masses of the orbitally excited singly, doubly, and triply bottom baryons are estimated. The isospin splitting is also determined, $M_{\\Xi_{bb}^{-}}-M_{\\Xi_{...

  7. Fast neutron induced fission of Np-237: mass spectra at high kinetic energies

    International Nuclear Information System (INIS)

    The results of measurements of the cold fragmentation mass spectra in neutron induced fission of Np-237 are discussed. The investigation of the cold fragmentation region of neptunium is needed in detail in order to understand the relationship between mass and charge subsystems inside the nucleus during all stage of a descent of the two-center figure from the fission barrier to the scission point. The twin gridded ionization chamber and data acquisition system used for the measurements are described. The fine structure of mass distributions which can be attributed to the role and behaviour of unpairing proton in neptunium is revealed. The conclusion is made that in comparison with any even-even compound system one proton in neptunium is free and can in principle join heavy fragment coming from light fragment. This effect is not specific property of the standard-I mass channel centered around magic fragment with mass m = 134 amu. Practically the same is observed for completely another channel: m = 152. It is very probable that the standard-II channel has the same properties

  8. Broken S_3 Flavor Symmetry of Leptons and Quarks: Mass Spectra and Flavor Mixing Patterns

    CERN Document Server

    Xing, Zhi-zhong; Zhou, Shun

    2010-01-01

    We apply the discrete S_3 flavor symmetry to both lepton and quark sectors of the standard model extended by introducing one Higgs triplet and realizing the type-II seesaw mechanism for finite neutrino masses. The resultant mass matrices of charged leptons (M_l), neutrinos (M_nu), up-type quarks (M_u) and down-type quarks (M_d) have a universal form consisting of two terms: one is proportional to the identity matrix I and the other is proportional to the democracy matrix D. We argue that the textures of M_l, M_u and M_d are dominated by the D term, while that of M_nu is dominated by the I term. This hypothesis implies a near mass degeneracy of three neutrinos and can naturally explain why the mass matrices of charged fermions are strongly hierarchical, why the quark mixing matrix is close to I and why the lepton mixing matrix contains two large angles. We discuss a rather simple perturbation ansatz to break the S_3 symmetry and obtain more realistic mass spectra of leptons and quarks as well as their flavor m...

  9. Dense Baryonic Matter

    International Nuclear Information System (INIS)

    Experiments on strangeness production in nucleus-nucleus collisions at SIS energies address fundamental aspects of modern nuclear physics: the determination of the nuclear equation-of-state at high baryon densities and the properties of hadrons in dense nuclear matter. Experimental data and theoretical results will be reviewed. Future experiments at the FAIR accelerator aim at the exploration of the QCD phase diagram at highest baryon densities. The proposal for the Compressed Baryonic Matter (CBM) experiment will be presented. (author)

  10. Mass spectra of B, Bs mesons using Dirac formalism with martin-like confinement potential

    International Nuclear Information System (INIS)

    The predictions of masses of heavy-light system for low-lying states of these open beauty mesons thus become important from the point of view of understanding the behaviour of quantum chromodynamics at this hadronic scale. More over, these are open flavour beauty mesons, their decays are dominated by weak interaction processes and are free from interference due to strong interaction processes. Thus the complete understanding of the spectroscopy and decay properties of these open flavour mesons becomes very important. Though there exist theoretical predictions for the low lying states of B, Bs mesons, their excited state predictions in view of the new observations in the energy range 5-6 GeV become topics of current interest. Here we study the mass spectra of B and Bs mesons in a relativistic framework

  11. Retrieval of Precise Radial Velocities from Near-Infrared High Resolution Spectra of Low Mass Stars

    CERN Document Server

    Gao, Peter; Gagné, Jonathan; Furlan, Elise; Bottom, Michael; Anglada-Escudé, Guillem; White, Russel; Davison, Cassy; Beichman, Charles; Brinkworth, Carolyn; Johnson, John; Ciardi, David; Wallace, James; Mennesson, Bertrand; von Braun, Kaspar; Vasisht, Gautam; Prato, Lisa; Kane, Stephen; Tanner, Angelle; Crawford, Timothy; Latham, David; Rougeot, Raphaël; Geneser, Claire; Catanzarite, Joseph

    2016-01-01

    Given that low-mass stars have intrinsically low luminosities at optical wavelengths and a propensity for stellar activity, it is advantageous for radial velocity (RV) surveys of these objects to use near-infrared (NIR) wavelengths. In this work we describe and test a novel RV extraction pipeline dedicated to retrieving RVs from low mass stars using NIR spectra taken by the CSHELL spectrograph at the NASA Infrared Telescope Facility, where a methane isotopologue gas cell is used for wavelength calibration. The pipeline minimizes the residuals between the observations and a spectral model composed of templates for the target star, the gas cell, and atmospheric telluric absorption; models of the line spread function, continuum curvature, and sinusoidal fringing; and a parameterization of the wavelength solution. The stellar template is derived iteratively from the science observations themselves without a need for separate observations dedicated to retrieving it. Despite limitations from CSHELL's narrow wavelen...

  12. Mass spectra-based framework for automated structural elucidation of metabolome data to explore phytochemical diversity

    Directory of Open Access Journals (Sweden)

    Fumio eMatsuda

    2011-08-01

    Full Text Available A novel framework for automated elucidation of metabolite structures in liquid chromatography-mass spectrometer (LC-MS metabolome data was constructed by integrating databases. High-resolution tandem mass spectra data automatically acquired from each metabolite signal were used for database searches. Three distinct databases, KNApSAcK, ReSpect, and the PRIMe standard compound database, were employed for the structural elucidation. The outputs were retrieved using the CAS metabolite identifier for identification and putative annotation. A simple metabolite ontology system was also introduced to attain putative characterization of the metabolite signals. The automated method was applied for the metabolome data sets obtained from the rosette leaves of 20 Arabidopsis accessions. Phenotypic variations in novel Arabidopsis metabolites among these accessions could be investigated using this method.

  13. Effect of Skimmer Cone Material on the Spectra of Inductively Coupled Plasma Mass Spectrometry

    International Nuclear Information System (INIS)

    The inductively coupled plasma ion source for mass spectrometry is very sensitive for multielement analysis with detection limits down to sub part per trillion (ppt). Polyatomic ions which could be formed in the mass spectra may interfere in the analysis of some element. Experimental conditions have great influences on the formation of polyatomic ions. The present work demonstrates that the skimmer materials (Au, Ag, Ni, and Cu) are participating in the formation of polyatomic ions, meanwhile the sampler materials have no real effect. The mechanism of formation of polyatomic ions is explained. Heats of formation of polyatomic species formed from the skimmer materials such as: Au X, Ag X, Ni X and Cu X; where X= Ar, O, N, C and H are calculated by Gaussian program (G 94 W)

  14. SYSTEMATIC UNCERTAINTIES IN BLACK HOLE MASSES DETERMINED FROM SINGLE-EPOCH SPECTRA

    International Nuclear Information System (INIS)

    We explore the nature of systematic errors that can arise in measurement of black hole masses from single-epoch (SE) spectra of active galactic nuclei (AGNs) by utilizing the many epochs available for NGC 5548 and PG1229+204 from reverberation mapping (RM) databases. In particular, we examine systematics due to AGN variability, contamination due to constant spectral components (i.e., narrow lines and host galaxy flux), data quality (i.e., signal-to-noise ratio (S/N)), and blending of spectral features. We investigate the effect that each of these systematics has on the precision and accuracy of SE masses calculated from two commonly used line width measures by comparing these results to recent RM studies. We calculate masses by characterizing the broad Hβ emission line by both the full width at half maximum and the line dispersion, and demonstrate the importance of removing narrow emission-line components and host starlight. We find that the reliability of line width measurements rapidly decreases for S/N lower than ∼ 10-20 (per pixel), and that fitting the line profiles instead of direct measurement of the data does not mitigate this problem but can, in fact, introduce systematic errors. We also conclude that a full spectral decomposition to deblend the AGN and galaxy spectral features is unnecessary, except to judge the contribution of the host galaxy to the luminosity and to deblend any emission lines that may inhibit accurate line width measurements. Finally, we present an error budget which summarizes the minimum observable uncertainties as well as the amount of additional scatter and/or systematic offset that can be expected from the individual sources of error investigated. In particular, we find that the minimum observable uncertainty in SE mass estimates due to variability is ∼20 pixel-1) spectra.

  15. Chemometric analysis of mass spectra of cis and trans fatty acid picolinyl esters

    DEFF Research Database (Denmark)

    Leth, Torben

    1997-01-01

    Capillary GC of fatty acid methyl esters with MS detection only yields information about the molecular weight of the compound. However, if picolinyl esters of fatty acids are analysed in this way it is possible to obtain more information about their structure, perhaps even the cis or trans...... a quadropole MS-detector. The mass spectra clearly show the molecular weight and the position of double bonds in the fatty acids, but whether the configuration is cis or trans is impossible to discern visually. However, with the use of principal component analysis, it is possible to distinguish...... between cis and trans fatty acids of C16:1, C18:1,n-9, C18:1,n-12, C18:2 and C22:1 in two- and three-dimensional score plots. With Soft Independent Modelling of Class Analogy (SIMCA), it is possible to calculate models that can predict from the mass spectra of unknown fatty acids whether they are of the...

  16. Extracting temperature and transverse flow by fitting transverse mass spectra and HBT radii together

    CERN Document Server

    He, Ronghua; Chen, Jianyi; Wu, Qingxin; Huo, Lei

    2016-01-01

    Single particle transverse mass spectra and HBT radii of identical pion and identical kaon are analyzed with a blast-wave parametrization under the assumptions local thermal equilibrium and transverse expansion. Under the assumptions, temperature parameter $T$ and transverse expansion rapidity $\\rho$ are sensitive to the shapes of transverse mass $m_\\text T$ spectrum and HBT radius $R_\\text{s}(K_\\text T)$. Negative and positive correlations between $T$ and $\\rho$ are observed by fitting $m_\\text{T}$ spectrum and HBT radius $R_\\text s (K_\\text T)$, respectively. For a Monte Carlo simulation using the blast-wave function, $T$ and $\\rho$ are extracted by fitting $m_T$ spectra and HBT radii together utilizing a combined optimization function $\\chi^2$. With this method, $T$ and $\\rho$ of the Monte Carlo sources can be extracted. Using this method for A Multi-Phase Transport model (AMPT) at RHIC energy, the differences of $T$ and $\\rho$ between pion and kaon are observed obviously, and the tendencies of $T$ and $\\r...

  17. Mass spectra in ${\\cal N}=1$ SQCD with additional colorless fields. Strong coupling regimes. II

    CERN Document Server

    Chernyak, Victor L

    2016-01-01

    This paper continues our studies in arXiV:1608.06452 [hep-th] of ${\\cal N}=1$ gauge theories in the strongly coupled regimes. We also consider here the ${\\cal N}=1$ SQCD-like theories with $SU(N_c)$ colors (and their Seiberg's dual), with $N_F$ flavors of light quarks and $N_F^2$ additional colorless flavored scalars $\\Phi^j_i$, but now with $N_F$ in the range $N_F>3N_c$. The mass spectra of these direct and dual theories in various vacua are calculated within the dynamical scenario introduced by the author in [8]. It assumes that quarks in such ${\\cal N}=1$ SQCD-like theories without elementary colored adjoint scalars can be in two {\\it standard} phases only. These are either the HQ (heavy quark) phase where they are confined or the Higgs phase. Recall that this scenario satisfies all those tests which were used as checks of the Seiberg hypothesis about the equivalence of the direct and dual theories. Calculated mass spectra of the direct $SU(N_c)$ theory are compared to those of its Seiberg's dual $SU(N_F-N...

  18. Evidence for chiral logarithms in the baryon spectrum

    CERN Document Server

    Walker-Loud, Andre

    2011-01-01

    Using precise lattice QCD computations of the baryon spectrum, we present the first direct evidence for the presence of contributions to the baryon masses which are non-analytic in the light quark masses; contributions which are often denoted "chiral logarithms". We isolate the poor convergence of SU(3) baryon chiral perturbation theory to the flavor-singlet mass combination. The flavor-octet baryon mass splittings, which are corrected by chiral logarithms at next to leading order in SU(3) chiral perturbation theory, yield baryon-pion axial coupling constants D, F, C and H consistent with QCD values; the first evidence of chiral logarithms in the baryon spectrum. The Gell-Mann--Okubo relation, a flavor-27 baryon mass splitting, which is dominated by chiral corrections from light quark masses, provides further evidence for the presence of non-analytic light quark mass dependence in the baryon spectrum; we simultaneously find the GMO relation to be inconsistent with the first few terms in a taylor expansion in ...

  19. Spectra identification and interpretation comparing the spectral informations - the example of infrared, C13 magnetic resonance and mass spectroscopy

    International Nuclear Information System (INIS)

    A computer assisted spectra interpretation based on special comparison was developed. The search program implements three different searching strategies to be used according to the specific analytical problem: Search for a spectrum of the same substance, partial structure search and spectra identification for mixed substances. It turned out, that the success of a search program depends significantly on the used spectra collection; optimization procedures involve the information content classification for each spectral information. A combined search program is demonstrated for infrared, 13C-NMR and mass spectra. (TW)

  20. Heavy baryons in the large Nc limit

    CERN Document Server

    Albertus, C; Fernando, I P; Goity, J L

    2015-01-01

    It is shown that in the large Nc limit heavy baryon masses can be estimated quantitatively in a 1/Nc expansion using the Hartree approximation. The results are compared with available lattice calculations for different values of the ratio between the square root of the string tension and the heavy quark mass tension independent of Nc. Using a potential adjusted to agree with the one obtained in lattice QCD, a variational analysis of the ground state spin averaged baryon mass is performed using Gaussian Hartree wave functions. Relativistic corrections through the quark kinetic energy are included. The results provide good estimates for the first sub-leading in 1/Nc corrections.

  1. Beautiful and other heavy baryons revisited

    Energy Technology Data Exchange (ETDEWEB)

    Martin, A.; Richard, J.M.

    1987-02-19

    We discuss the mass range for the beautiful baryons ..lambda../sub b/, ..sigma../sub b/ and ..sigma../sub b//sup */ allowed by rigorous inequalities which are derived in the framework of potential models but have probably a broader domain of validity. We obtain at the same time lower bounds on the masses of other baryons. We also compare the numerical prediction of several explicit models. There are convergent indications towards a mass of about 5.6 GeV for the ..lambda../sub b/.

  2. Net-Baryon Physics: Basic Mechanisms

    International Nuclear Information System (INIS)

    How does the fraction of energy carried by the net-baryon, B - anti-B , evolve as a function of the centre-of-mass collisional energy per nucleon, sqrt(s)? In order to answer this question we explore the net-baryon mechanism and it is propose a simple but consistent model for net-baryon production in high energy hadron-hadron, hadron-nucleus and nucleus-nucleus collisions. The model basic ingredients are: valence string formation based on standard PDFs with QCD evolution; and string fragmentation via the Schwinger mechanism. Our model shows that a good description of the main features of net-baryon data is possible in the framework of a simplistic model, with the advantage of making the fundamental production mechanisms manifest. We compare results both with data and existing models. (authors)

  3. Baryon number transport at LHC energies with the ALICE experiment

    OpenAIRE

    Christakoglou, P.(Nikhef, National Institute for Subatomic Physics, Amsterdam, The Netherlands); Botje, M.A.J.; Mischke, A.; Van Leeuwen, M

    2009-01-01

    Particle yields along with the ratios of particle production in hadronic interactions are important indicators of the collision dynamics. In particular, the detailed analysis of the baryon spectra as well as that of p¯/p and L¯ /L ratios are of great importance since they allow to determine the carrier of the baryon number (BN). In this paper, the expected performance of the ALICE detector setup regarding the baryon spectra, the rapidity and transversemomentum dependence of the ¯ p/p and L¯ /...

  4. Expert system for estimates of molecular weights of volatile organic compounds from low-resolution mass spectra

    Energy Technology Data Exchange (ETDEWEB)

    Scott, D.R.

    1991-01-01

    MAXMASS, the highest mass with an intensity of 5% of the base peak in a low resolution mass spectrum, has been found to be linearly correlated with the true molecular weights of 400 randomly selected spectra, yielding a family of parellel lines. A simple expert system using MAXMASS has been developed to estimate molecular weights of unknown volatile compounds from their mass spectra. This is an empirical rule-based system which will run on a personal computer. It consists of a classification module chained to separate molecular weight prediction modules for six classes. These are benzenes; chlorobenzenes; bromoalkenes/alkenes; mono- and dichloroalkanes/alkenes; tri-, tetra- and pentachloroalkanes/alkenes; and unknown (other) classes. The rules were derived from National Institute of Standards and Technology (NIST) reference spectra of 75 target toxic compounds from the first five classes and 32 from the unknown class. Performance tests of molecular weight predictions were made with the expert system and the Self Training interpretive and Retrieval System (STIRS) on NIST reference spectra of the 107 training compounds; on a set of 32 test NIST reference spectra of other compounds found in air samples; on a set of 100 randomly selected NIST reference spectra; and on 30 spectra taken from actual field gas chromatography/mass spectrometry samples.

  5. Diquark structure of baryons

    International Nuclear Information System (INIS)

    Three body calculations for studying the baryons are performed in a non-relativistic treatment with three quarks interacting via Bhaduri's potential. From the resulting wave functions, it is analysed under which conditions can a diquark structure occurs. Several photos showing quark distributions inside the baryons are presented and discussed in details

  6. Energy spectra of massive two-body decay products and mass measurement

    Science.gov (United States)

    Agashe, Kaustubh; Franceschini, Roberto; Hong, Sungwoo; Kim, Doojin

    2016-04-01

    We have recently established a new method for measuring the mass of unstable particles produced at hadron colliders based on the analysis of the energy distribution of a mass less product from their two-body decays. The central ingredient of our proposal is the remarkable result that, for an unpolarized decaying particle, the location of the peak in the energy distribution of the observed decay product is identical to the (fixed) value of the energy that this particle would have in the rest-frame of the decaying particle, which, in turn, is a simple function of the involved masses. In addition, we utilized the property that this energy distribution is symmetric around the location of peak when energy is plotted on a logarithmic scale. The general strategy was demonstrated in several specific cases, including both beyond the standard model particles, as well as for the top quark. In the present work, we generalize this method to the case of a massive decay product from a two-body decay; this procedure is far from trivial because (in general) both the above-mentioned properties are no longer valid. Nonetheless, we propose a suitably modified parametrization of the energy distribution that was used successfully for the massless case, which can deal with the massive case as well. We test this parametrization on concrete examples of energy spectra of Z bosons from the decay of a heavier supersymmetric partner of top quark (stop) into a Z boson and a lighter stop. After establishing the accuracy of this parametrization, we study a realistic application for the same process, but now including dominant backgrounds and using foreseeable statistics at LHC14, in order to determine the performance of this method for an actual mass measurement. The upshot of our present and previous work is that, in spite of energy being a Lorentz-variant quantity, its distribution emerges as a powerful tool for mass measurement at hadron colliders.

  7. Generalized focus point and mass spectra comparison of highly natural SUGRA GUT models

    Science.gov (United States)

    Baer, Howard; Barger, Vernon; Savoy, Michael

    2016-04-01

    Supergravity grand unified models (SUGRA GUTs) are highly motivated and allow for a high degree of electroweak naturalness when the superpotential parameter μ ˜100 - 300 GeV (preferring values closer to 100 GeV). We first illustrate that models with radiatively driven naturalness enjoy a generalized focus-point behavior wherein all soft terms are correlated instead of just scalar masses. Next, we generate spectra from four SUGRA GUT archetypes: 1. S O (10 ) models where the Higgs doublets live in different ten-dimensional irreducible representations (irreps), 2. models based on S O (10 ) where the Higgs multiplets live in a single ten-dimensional irrep but with D -term scalar mass splitting, 3. models based on S U (5 ), and 4. a more general SUGRA model with 12 independent parameters. Electroweak naturalness implies for all models a spectrum of light Higgsinos with mW˜1,Z˜ 1 ,2≲300 GeV and gluinos with mg ˜≲ 2 - 4 TeV . However, masses and mixing in the third generation sfermion sector differ distinctly between the models. These latter differences would be most easily tested at a linear e+e- collider with √{s }˜ multi-TeV scale but measurements at a 50-100 TeV hadron collider are also possible.

  8. Generalized focus point and mass spectra comparison of highly natural SUGRA GUT models

    CERN Document Server

    Baer, Howard; Savoy, Michael

    2016-01-01

    Supergravity grand unified models (SUGRA GUTs) are highly motivated and allow for a high degree of electroweak naturalness when the superpotential parameter mu~ 100-300 GeV (preferring values closer to 100 GeV). We first illustrate that models with radiatively-driven naturalness enjoy a generalized focus-point behavior wherein all soft terms are correlated instead of just scalar masses. Next, we generate spectra from four SUGRA GUT archetypes: 1. SO(10) models where the Higgs doublets live in different 10-dimensional irreducible representations (irreps), 2. models based on SO(10) where the Higgs multiplets live in a single 10-dimensional irrep but with D-term scalar mass splitting, 3. models based on SU(5) and 4. a more general SUGRA model with 12 independent parameters. Electroweak naturalness implies for all models a spectrum of light higgsinos with m(higgsinos)< 300 GeV and gluinos with m(gluino)< 2-4 TeV. However, masses and mixing in the third generation sfermion sector differ distinctly between th...

  9. Mass spectra in ${\\cal N}=1$ SQCD with additional colorless fields. Strong coupling regimes

    CERN Document Server

    Chernyak, Victor L

    2016-01-01

    We consider the ${\\cal N}=1$ $SU(N_c)$ SQCD-like (direct) theory (and its Seiberg's dual with $SU(N_F-N_c)$ dual colors), and with $N_F$ flavors of light quarks ${\\overline Q}_j, Q^i$ with the mass term in the superpotential $m_Q{\\rm Tr}({\\overline Q} Q),\\,\\, m_Q\\ll\\Lambda$. Besides, there are $N_F^2$ additional colorless but flavored fields $\\Phi^j_i$ with the large mass parameter $\\mu_{\\Phi}\\gg\\Lambda$. But now considered is the region $N_c+1mass spectra of this direct theory in various vacua and at different values of $\\mu_{\\Phi}$ are calculated within the dynamical scenario introduced by the author in [9]. This scenario assumes that quarks in such ${\\cal N}=1$ SQCD-like theories can be in two standard phases only. These are either the HQ (heavy quark) phase where they are confined or the Higgs phase. It is shown that due to the strong powerlike RG evolution, the seemingly heavy and dynamically ...

  10. Calibration of matrix-assisted laser desorption/ionization time-of-flight peptide mass fingerprinting spectra

    DEFF Research Database (Denmark)

    Hjernø, Karin; Højrup, Peter

    2007-01-01

    This chapter describes a number of aspects important for calibration of matrix-assisted laser desorption/ionization time-of-flight spectra prior to peptide mass fingerprinting searches. Both multipoint internal calibration and mass defect-based calibration is illustrated. The chapter describes how...

  11. Investigation of Spectra (NMR, Mass) of Some Fe3S3 Cluster Compounds

    Institute of Scientific and Technical Information of China (English)

    刘平; 王艰; 陈忠; 彭奇

    2000-01-01

    The chemical shifts of 1H-NMR of five Fe3S3 cluster compounds wereassigned. The main chemical shift values are: δcH3 = 1. 095 - 1. 946, δCH2 = 2. 882 -3.803, δC6Hn = 7. 547 7. 172. In comparison with those of pure (CH3CH2)3N andthiophenol, these values are moved to high position, and the width of these peaks is ob-viously increased. These characteristics conformed to NMR spectra of paramagneticcompounds and their molecular structures. The paramagnetic property of these com-pounds was also studied with ESR spectrum. Mass spectra of three compounds were de-termined. The main fragments were observed, for example, m/z: 130 [(C2H5)4N]+,264[Fe3S3] +, 144[Fe-S-Fe] +, 120[S-Fe-S]+, 88[Fe-S]+, 136[FeBr]+, 91[FeCl] + etc. These supported structural characteristics of the anion skeleton and molecules strongly. The possible mechanism of fragmentation was discussed.

  12. Measurement of energy spectra on irradiated polycrystalline UO2 samples using secondary ion mass spectrometry

    International Nuclear Information System (INIS)

    The energy spectrum of uranium in irradiated fuels is known to give key information on the oxidation state of uranium at the sample surface. In this respect, it is essential to know the operating conditions applied to measure energy spectra by secondary ion mass spectrometry in order to obtain reliable data. Using a focussed beam on CAMECA IMS6f, the acquisition of an energy spectrum is performed along a line on the sample surface because the primary beam position moves as a function of the high voltage. Depending on the size of UO2 grains, the analysed area can be limited within one single grain or spread among many grains. The consequences of such acquisition conditions are discussed in this paper. (authors)

  13. Chemometric analysis of mass spectra of cis and trans fatty acid picolinyl esters

    DEFF Research Database (Denmark)

    Leth, Torben

    1997-01-01

    configuration. Picolinyl esters of fatty acids are prepared by adding carbonyl-diimidazole, 3-hydroxy-methylpyridine and 4-pyrrolidin-o-pyridine to a solution of free fatty acids in dichloromethane. The picolinyl esters dissolved in heptane are then separated by capillary GC on a CP Sil 88 column equipped with...... between cis and trans fatty acids of C16:1, C18:1,n-9, C18:1,n-12, C18:2 and C22:1 in two- and three-dimensional score plots. With Soft Independent Modelling of Class Analogy (SIMCA), it is possible to calculate models that can predict from the mass spectra of unknown fatty acids whether they are of the...

  14. Neutron-encoded signatures enable product ion annotation from tandem mass spectra.

    Science.gov (United States)

    Richards, Alicia L; Vincent, Catherine E; Guthals, Adrian; Rose, Christopher M; Westphall, Michael S; Bandeira, Nuno; Coon, Joshua J

    2013-12-01

    We report the use of neutron-encoded (NeuCode) stable isotope labeling of amino acids in cell culture for the purpose of C-terminal product ion annotation. Two NeuCode labeling isotopologues of lysine, (13)C6(15)N2 and (2)H8, which differ by 36 mDa, were metabolically embedded in a sample proteome, and the resultant labeled proteins were combined, digested, and analyzed via liquid chromatography and mass spectrometry. With MS/MS scan resolving powers of ~50,000 or higher, product ions containing the C terminus (i.e. lysine) appear as a doublet spaced by exactly 36 mDa, whereas N-terminal fragments exist as a single m/z peak. Through theory and experiment, we demonstrate that over 90% of all y-type product ions have detectable doublets. We report on an algorithm that can extract these neutron signatures with high sensitivity and specificity. In other words, of 15,503 y-type product ion peaks, the y-type ion identification algorithm correctly identified 14,552 (93.2%) based on detection of the NeuCode doublet; 6.8% were misclassified (i.e. other ion types that were assigned as y-type products). Searching NeuCode labeled yeast with PepNovo(+) resulted in a 34% increase in correct de novo identifications relative to searching through MS/MS only. We use this tool to simplify spectra prior to database searching, to sort unmatched tandem mass spectra for spectral richness, for correlation of co-fragmented ions to their parent precursor, and for de novo sequence identification. PMID:24043425

  15. Neutron-encoded Signatures Enable Product Ion Annotation From Tandem Mass Spectra*

    Science.gov (United States)

    Richards, Alicia L.; Vincent, Catherine E.; Guthals, Adrian; Rose, Christopher M.; Westphall, Michael S.; Bandeira, Nuno; Coon, Joshua J.

    2013-01-01

    We report the use of neutron-encoded (NeuCode) stable isotope labeling of amino acids in cell culture for the purpose of C-terminal product ion annotation. Two NeuCode labeling isotopologues of lysine, 13C615N2 and 2H8, which differ by 36 mDa, were metabolically embedded in a sample proteome, and the resultant labeled proteins were combined, digested, and analyzed via liquid chromatography and mass spectrometry. With MS/MS scan resolving powers of ∼50,000 or higher, product ions containing the C terminus (i.e. lysine) appear as a doublet spaced by exactly 36 mDa, whereas N-terminal fragments exist as a single m/z peak. Through theory and experiment, we demonstrate that over 90% of all y-type product ions have detectable doublets. We report on an algorithm that can extract these neutron signatures with high sensitivity and specificity. In other words, of 15,503 y-type product ion peaks, the y-type ion identification algorithm correctly identified 14,552 (93.2%) based on detection of the NeuCode doublet; 6.8% were misclassified (i.e. other ion types that were assigned as y-type products). Searching NeuCode labeled yeast with PepNovo+ resulted in a 34% increase in correct de novo identifications relative to searching through MS/MS only. We use this tool to simplify spectra prior to database searching, to sort unmatched tandem mass spectra for spectral richness, for correlation of co-fragmented ions to their parent precursor, and for de novo sequence identification. PMID:24043425

  16. Automated Glycan Sequencing from Tandem Mass Spectra of N-Linked Glycopeptides.

    Science.gov (United States)

    Yu, Chuan-Yih; Mayampurath, Anoop; Zhu, Rui; Zacharias, Lauren; Song, Ehwang; Wang, Lei; Mechref, Yehia; Tang, Haixu

    2016-06-01

    Mass spectrometry has become a routine experimental tool for proteomic biomarker analysis of human blood samples, partly due to the large availability of informatics tools. As one of the most common protein post-translational modifications (PTMs) in mammals, protein glycosylation has been observed to alter in multiple human diseases and thus may potentially be candidate markers of disease progression. While mass spectrometry instrumentation has seen advancements in capabilities, discovering glycosylation-related markers using existing software is currently not straightforward. Complete characterization of protein glycosylation requires the identification of intact glycopeptides in samples, including identification of the modification site as well as the structure of the attached glycans. In this paper, we present GlycoSeq, an open-source software tool that implements a heuristic iterated glycan sequencing algorithm coupled with prior knowledge for automated elucidation of the glycan structure within a glycopeptide from its collision-induced dissociation tandem mass spectrum. GlycoSeq employs rules of glycosidic linkage as defined by glycan synthetic pathways to eliminate improbable glycan structures and build reasonable glycan trees. We tested the tool on two sets of tandem mass spectra of N-linked glycopeptides cell lines acquired from breast cancer patients. After employing enzymatic specificity within the N-linked glycan synthetic pathway, the sequencing results of GlycoSeq were highly consistent with the manually curated glycan structures. Hence, GlycoSeq is ready to be used for the characterization of glycan structures in glycopeptides from MS/MS analysis. GlycoSeq is released as open source software at https://github.com/chpaul/GlycoSeq/ . PMID:27111718

  17. Quark-Pauli effects in three octet-baryons

    CERN Document Server

    Nakamoto, C

    2016-01-01

    To sustain a neutron star with about two times the solar mass, multi baryons including hyperons are expected to produce repulsive effects in the interior of its high baryon-density region. To examine possible quark-Pauli repulsion among the baryons, we solve the eigenvalue problem of the quark antisymmetrizer for three octet-baryons that are described by most compact spatial configurations. We find that the Pauli blocking effect is weak in the $\\Lambda nn$ system, while it is strong in the $\\Sigma^-nn$ system. The appearance of the $\\Sigma^-$ hyperon is suppressed in the neutron star interior but no quark-Pauli repulsion effectively works for the $\\Lambda$ hyperon.

  18. Heavy flavor baryons in hypercentral model

    Indian Academy of Sciences (India)

    Bhavin Patel; Ajay Kumar Rai; P C Vinodkumar

    2008-05-01

    Heavy flavor baryons containing single and double charm (beauty) quarks with light flavor combinations are studied using the hypercentral description of the three-body problem. The confinement potential is assumed as hypercentral Coulomb plus power potential with power index . The ground state masses of the heavy flavor, $J^{P} = \\dfrac{1}{2}^{+}$ and $\\dfrac{3}{2}^{+}$ baryons are computed for different power indices, starting from 0.5 to 2.0. The predicted masses are found to attain a saturated value in each case of quark combinations beyond the power index = 1.0.

  19. Dipion decays of heavy baryons

    International Nuclear Information System (INIS)

    Compared with the charmed baryons, the bottom baryons are not known very well both experimentally and theoretically. In this paper, we investigate the dipion strong decays of the P-wave and D-wave excited bottom baryons in the framework of the QPC model. We also extend the same analysis to the charmed baryons

  20. An Attempt to Study Pentaquark Baryons in String Theory

    OpenAIRE

    Sugamoto, Akio

    2004-01-01

    An attempt to study recently observed Pentaquark baryons is performed in the dual string theory of QCD. Mass formulae for Pentaquark baryons are naively estimated in the Maldacena's prototype model for supersymmetric QCD and a more realistic model for the ordinary QCD.

  1. Soliton solutions of Chiral Born-Infeld Theory and baryons

    OpenAIRE

    Pavlovsky, Oleg V.

    2003-01-01

    Finite-energy topological spherically symmetrical solutions of Chiral Born-Infeld Theory are studied. Properties of these solution are obtained, and a possible physical interpretation is also given. We compute static properties of baryons (mass,main radius, magnetic main radius, axial coupling constant) whose solutions can be interpreted as the baryons of QCD.

  2. Galaxy And Mass Assembly (GAMA) blended spectra catalogue: strong galaxy-galaxy lens and occulting galaxy pair candidates

    OpenAIRE

    Holwerda, B.W.; Baldry, I. K.; Alpaslan, M.; Bauer, A; Bland-Hawthorn, J.; Brough, S.; Brown, M. J. I.; Cluver, M. E.; Conselice, C; Driver, S. P.; Hopkins, A. M.; Jones, D.H.; López-Sánchez, Á. R.; Loveday, J; Meyer, M J

    2015-01-01

    We present the catalogue of blended galaxy spectra from the Galaxy And Mass Assembly (GAMA) survey. These are cases where light from two galaxies are significantly detected in a single GAMA fibre. Galaxy pairs identified from their blended spectrum fall into two principal classes: they are either strong lenses, a passive galaxy lensing an emission-line galaxy; or occulting galaxies, serendipitous overlaps of two galaxies, of any type. Blended spectra can thus be used to reliably identify stro...

  3. Staggered Heavy Baryon Chiral Perturbation Theory

    CERN Document Server

    Bailey, Jon A

    2007-01-01

    Although taste violations significantly affect the results of staggered calculations of pseudoscalar and heavy-light mesonic quantities, those entering staggered calculations of baryonic quantities have not been quantified. Here I develop staggered chiral perturbation theory in the light-quark baryon sector by mapping the Symanzik action into heavy baryon chiral perturbation theory. For 2+1 dynamical quark flavors, the masses of flavor-symmetric nucleons are calculated to third order in partially quenched and fully dynamical staggered chiral perturbation theory. To this order the expansion includes the leading chiral logarithms, which come from loops with virtual decuplet-like states, as well as terms the order of the cubed pion mass, which come from loops with virtual octet-like states. Taste violations enter through the meson propagators in loops and tree-level terms the order of the squared lattice spacing. The pattern of taste symmetry breaking and the resulting degeneracies and mixings are discussed in d...

  4. Photoproduction of hermaphrodite baryons

    International Nuclear Information System (INIS)

    We show that photoexcitation of the lightest hermaphrodite baryons is strongly suppressed from proton targets but allowed from neutrons, a result that is reminiscent of a quark model selection rule due to Moorhouse. This is consistent with suggestions that the P11 (1710) is the lightest q3G baryon and eliminates the possibility of considerable mixing of q3G into the nucleon and delta's Fock space wavefunctions. (orig.)

  5. Baryon stopping and charged particle production from lead-lead collisions at 158 GeV per nucleon

    International Nuclear Information System (INIS)

    Net proton (proton minus antiproton) and negative charge hadron spectra (h-) from central Pb+Pb collisions at 158 GeV per nucleon at the CERN Super Proton Synchrotron were measured and compared to spectra from central collisions of the lighter S+S system. Net baryon distributions were derived from those of net protons and net lambdas. Stopping, or rapidity shift with respect to the beam, of net protons and net baryons increase with system size. The mean transverse momentum T>60;T>62; of net protons also increase with system size. The h- rapidity density scales with the number of participant nucleons for nuclear collisions, where their T>60;T>62; is independent of system size. The T>60;T>62; dependence upon particle mass and system size is consistent with larger transverse flow velocity at midrapidity for central collisions of Pb+Pb compared to that of S+S

  6. Manifestation of Conformal Symmetry in the Light Flavor Baryon Sector

    International Nuclear Information System (INIS)

    On the AdS5 cone, conformally compactified to R1 x S3, a quark-diquark model of light flavor baryons is developed. The system on this manifold is described in terms of a scalar conformal equation, gauged by the field of a D3 brane whose transversal dimensions have been conformally wrapped over R1 x S3. Such a system does not result exactly conformally invariant because the gauge potential slightly modifies the conformal centrifugal barrier of the free geodesic motion. Thanks to this, the model describes the correct mass ordering in the P11-S11 pairs through the spectra as a combined effect of conformal symmetry breaking, on the one side, and a parity change of the diquark from a scalar at low masses, to a pseudoscalar at higher masses, on the other. We calculate the number of resonances with masses below 2500 MeV needed for the completeness of the above scheme and find a total of 32 ''missing'' nucleon and states. Their absence or presence in the respective spectra relates to the degree to which conformal symmetry is realized in the lightest flavor sector. The scheme also allows for a prediction of the dressing function of an effective instantaneous gluon propagator from the Fourier transform of the gauge potential. We find a dressing function that is finite in the infrared and tends to zero at infinity.

  7. Electron spectra in B-meson decays, ARGUS data and the t-quark mass

    Energy Technology Data Exchange (ETDEWEB)

    Dobrovolskaya, A.V.; Ter-Martirosyan, K.A.; Veselov, A.I. (Institut Teoreticheskoj i Ehksperimental' noj Fiziki, Moscow (USSR))

    1991-03-28

    Spectra of electrons produced in semileptonic B-meson decay into a multihadron final state, calculated recently, are used in combination with the Bauer, Stech and Wirbel results, to fit the new ARGUS data. A value of {lambda}=vertical strokeV{sub ub}/V{sub cb}vertical stroke=0.13+-0.01 which gives the best fit of them is used together with data on B{sup 0}-anti B{sup 0} and K{sub 1}{sup 0}-K{sub 2}{sup 0} transitions, to determine the t quark mass. The result is m{sub t}=130+-40 GeV, {delta}'=180deg-{delta}=(23+-14)deg, vertical strokeV{sub td}/V{sub cb}vertical stroke=0.34+-0.01, where the main part of the errors are due to the uncertainty in f'{sub B}=B{sup 1/2}f{sub B} and in B{sub K}. (orig.).

  8. Charmed baryons in bootstrap quark model

    OpenAIRE

    Gerasyuta, S. M.; Ivanov, D.V.

    2001-01-01

    In the framework of dispersion relation technique the relativistic three-quark equations including heavy quarks are found. The approximate solutions of the relativistic three-particles equations based on the extraction of leading singularities of amplitudes are obtained. The mass values of S-wave multiplets of charmed baryons are calculated.

  9. Doubly Heavy Tetraquarks and Baryons

    Directory of Open Access Journals (Sweden)

    Karliner Marek

    2014-04-01

    Full Text Available During the last three years strong experimental evidence from B and charm factories has been accumulating for the existence of exotic hadronic quarkonia, narrow resonances which cannot be made from a quark and an antiquark. Their masses and decay modes show that they contain a heavy quark-antiquark pair, but their quantum numbers are such that they must also contain a light quark-antiquark pair. The theoretical challenge has been to determine the nature of these resonances. The main possibilities are that they are either "genuine tetraquarks", i.e. two quarks and two antiquarks within one confinement volume, or "hadronic molecules" of two heavy-light mesons. In the last few months there as been more and more evidence in favor of the latter. I discuss the experimental data and its interpretation and provide fairly precise predictions for masses and quantum numbers of the additional exotic states which are naturally expected in the molecular picture but have yet to be observed. In addition, I provide arguments in favor of the existence of an even more exotic state – a hypothetical deuteron-like bound state of two heavy baryons. I also consider “baryon-like" states QQ' q¯q¯′$\\bar q\\bar q\\prime $, which if found will be direct evidence not just for near-threshold binding of two heavy mesons, but for genuine tetraquarks with novel color networks. I stress the importance of experimental search for doubly-heavy baryons in this context.

  10. Baryon Dynamics, Dark Matter Substructure, and Galaxies

    CERN Document Server

    Weinberg, D H; Davé, R; Katz, N; Colombi, Stephane; Dav\\'e, Romeel; Katz, Neal; Weinberg, David H.

    2006-01-01

    By comparing a collisionless cosmological N-body simulation (DM) to an SPH simulation with the same initial conditions, we investigate the correspondence between the dark matter subhalos produced by collisionless dynamics and the galaxies produced by dissipative gas dynamics in a dark matter background. When galaxies in the SPH simulation become satellites in larger groups, they retain local dark matter concentrations (SPH subhalos) whose mass is typically five times their baryonic mass. The more massive subhalos of the SPH simulation have corresponding subhalos of similar mass and position in the DM simulation; at lower masses, there is fairly good correspondence, but some DM subhalos are in different spatial positions and some suffer tidal stripping or disruption. The halo occupation statistics of DM subhalos -- the mean number of subhalos, pairs, and triples as a function of host halo mass -- are very similar to those of SPH subhalos and SPH galaxies. Gravity of the dissipative baryon component amplifies t...

  11. Wavelet analysis of baryon acoustic structures in the galaxy distribution

    OpenAIRE

    Arnalte-Mur, P.; Labatie, A.; Clerc, N.; Martínez, V. J.; Starck, J.-L.; Lachièze-Rey, M.; Saar, E; Paredes, S.

    2012-01-01

    Baryon Acoustic Oscillations (BAO) are a feature imprinted in the density field by acoustic waves travelling in the plasma of the early universe. Their fixed scale can be used as a standard ruler to study the geometry of the universe. BAO have been previously detected using correlation functions and power spectra of the galaxy distribution. In this work, we present a new method for the detection of the real-space structures associated with this feature. These baryon acoustic structures are sp...

  12. DETERMINATION OF CHEMICAL CLASSES FROM MASS SPECTRA OF TOXIC ORGANIC COMPOUNDS BY SIMCA PATTERN RECOGNITION AND INFORMATION THEORY

    Science.gov (United States)

    The low resolution mass spectra of a set of 78 toxic volatile organic compounds were examined for information concerning chemical classes. These compounds were predominately chloro- and/or bromoaromatics, -alkanes, or -alkenes, which are routinely sought at trace levels in ambien...

  13. Chiral extrapolations and strangeness in the baryon ground states

    CERN Document Server

    Lutz, Matthias F M

    2013-01-01

    We review the quark-mass dependence of the baryon octet and decuplet masses as obtained from recent lattice simulations of the BMW, PACS-CS, LHPC, HSC and QCDSF-UKQCD groups. Our discussion relies on the relativistic chiral Lagrangian and large-$N_c$ sum rule estimates of the counter terms relevant for the baryon masses at N$^3$LO. A partial summation is implied by the use of physical baryon and meson masses in the one-loop contributions to the baryon self energies. In our analysis the physical masses are reproduced exactly by means of a suitable set of linear constraints. A quantitative and simultaneous description of all lattice results is achieved in terms of a six parameter fit, where the symmetry conserving counter term that are relevant at N$^3$LO are not yet being used. For pion masses larger than 300 MeV there appears to be an approximate linear pion-mass dependence of all octet and decuplet baryon masses. We discuss the pion- and strangeness sigma terms of the baryon octet states.

  14. Physical properties of the chiral quantum baryon

    International Nuclear Information System (INIS)

    It is presented an account to understand the quantum chiral baryon, which a stable chiral soliton with baryon number one obtained after first quantization by collective coordinates. Starting from the exact series solution to the non-linear sigma model with the hedge-hog configuration, the values of several physical quantities (mass, axial weak coupling, gyromagnetic ratios and radii) as a function of the order of Pade approximants used as approximanted representations of the solution, are calculated. It turns out that consistent results may be obtained, but a better approximation should be developed. (author)

  15. Properties of doubly and triply heavy baryons

    International Nuclear Information System (INIS)

    We calculate the mass and residue of the doubly/triply heavy spin-1/2 and spin- 3/2 baryons containing two/three heavy b or c quarks in the framework of QCD sum rules. We use the most general interpolating currents in symmetric and anti-symmetric forms with respect to the exchange of heavy quarks, to calculate the two-point correlation functions describing the baryons under consideration. A comparison of the obtained results with the existing experimental data as well as predictions of other theoretical approaches is also made

  16. Infrared enhancement in single-baryon systems

    CERN Document Server

    Lv, Songlin

    2016-01-01

    The pion-baryon triangle diagram is inspected for the special kinematic region in which the squared momentum transfer is close to $4m_\\pi^2$. The pion propagators can have very small energies, as opposed to $\\sim m_\\pi$ in the physical region, which allows the nucleon propagator to be near its mass shell. This observation leads us to conclude that in this particular domain the triangle diagram is augmented by $\\mathcal{O}(m_N/m_\\pi)$ compared with the standard counting of chiral perturbation theory, hence an infrared enhancement in the single-baryon sector.

  17. The Halo Masses and Galaxy Environments of Hyperluminous QSOs at z ≃ 2.7 in the Keck Baryonic Structure Survey

    OpenAIRE

    Trainor, Ryan F.; Steidel, Charles C.

    2012-01-01

    We present an analysis of the galaxy distribution surrounding 15 of the most luminous (≳10^(14) L_☉; M_1450 ≃ –30) QSOs in the sky with z ≃ 2.7. Our data are drawn from the Keck Baryonic Structure Survey, which has been optimized to examine the small-scale interplay between galaxies and the intergalactic medium during the peak of the galaxy formation era at z ~ 2-3. In this work, we use the positions and spectroscopic redshifts of 1558 galaxies that lie within ~3' (4.2 h^(–1) comoving Mpc; c...

  18. Measurement of Branching Fractions and Mass Spectra of B to K pi pi gamma

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; /Annecy, LAPP; Grauges, E.; /Barcelona, IFAE; Palano, A.; Pappagallo, M.; Pompili, A.; /Bari U. /INFN, Bari; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; /Beijing, Inst. High Energy Phys.; Eigen, G.; Ofte, I.; Stugu, B.

    2005-07-12

    The authors present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B {yields} K{pi}{pi}{gamma} in the range m{sub K{pi}{pi}} < 1.8 GeV/c{sup 2}. They reconstruct four final states: K{sup +}{pi}{sup -}{pi}{sup +}{gamma}, K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}, K{sub S}{sup 0}{pi}{sup -}{pi}{sup +}{gamma}, and K{sub S}{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}, where K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}. Using 232 million e{sup +}e{sup -} {yields} B{bar B} events recorded by the BABAR experiment at the PEP-II asymmetric-energy storage ring, they measure the branching fractions {Beta}(B{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +}{gamma}) = (2.95 {+-} 0.13(stat.) {+-} 0.20(syst)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}{gamma}) = (4.07 {+-} 0.22(stat.) {+-} 0.31(syst.)) x 10{sup -5}, {Beta}(B{sup 0} {yields} K{sup 0}{pi}{sup +}{pi}{sup -}{gamma}) = (1.85 {+-} 0.21(stat.) {+-} 0.12(syst.)) x 10{sup -5}, and {Beta}(B{sup +} {yields} K{sup 0}{pi}{sup +}{pi}{sup 0}{gamma}) = (4.56 {+-} 0.42(stat.) {+-} 0.31(syst.)) x 10{sup -5}.

  19. Variety identification of wheat using mass spectrometry with neural networks and the influence of mass spectra processing prior to neural network analysis

    DEFF Research Database (Denmark)

    Sørensen, Helle Aagaard; Sperotto, Maria Maddalena; Petersen, M.;

    2002-01-01

    preprocessing mass spectrometric data. The number of wheat varieties tested was increased from 10 to 30. The main pre-processing method investigated was based on Gaussian smoothing of the spectra, but other methods based on normalisation procedures and multiplicative scatter correction of data were also used....... With the final method, it was possible to classify 30 wheat varieties with 87% correctly classified mass spectra and a correlation coefficient of 0.90.......The performance of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry with neural networks in wheat variety classification is further evaluated.(1) Two principal issues were studied: (a) the number of varieties that could be classified correctly; and (b) various means of...

  20. Quark cluster model of baryon-baryon interaction

    International Nuclear Information System (INIS)

    The quark cluster model of the baryon-baryon interaction is reviewed. The emphasis is on the foundation of the approach and the main features of the model. The origins of the short-range repulsion in the nuclear force and other baryonic interactions are discussed. (author)

  1. Supersymmetric Baryonic Branes

    CERN Document Server

    Gomis, J P; Simón, J; Townsend, P K; Gomis, Joaquim; Ramallo, Alfonso V.; Simon, Joan; Townsend, Paul K.

    1999-01-01

    We derive an energy bound for a `baryonic' D5-brane probe in the $adS_5\\times S^5$ background near the horizon of $N$ D3-branes. Configurations saturating the bound are shown to be 1/4 supersymmetric $S^5$-wrapped D5-branes with $N$ singularities at arbitrary positions. Previous results for $N$ coincident singularities are recovered as a special case. We derive a similar energy bound for a `baryonic' M5-brane probe in the background of $N$ M5-branes. Configurations saturating the bound are again 1/4 supersymmetric and, in the $adS_7\\times S^4$ near-horizon limit, provide a worldvolume realization of the `baryon string' vertex of the (2,0)-supersymmetric six-dimensional conformal field theory on coincident M5-branes. For the full M5-background we find a worldvolume realization of the Hannany-Witten effect in M-theory.

  2. Baryon production at PEP

    International Nuclear Information System (INIS)

    Measurements of inclusive Λ + anti Λ production for 1.0 less than or equal to p less than or equal to 10.0 GeV/c and p + anti p production for 0.4 less than or equal to p less than or equal to 2.0 GeV/c show significant baryon production in e+e- annihilation at E/sub cm/ = 29 GeV. Λ + anti Λ production represents 0.2 Λ's or anti Λ's per PEP event while the observed p + anti p production implies all baryon-antibaryon pair production is occurring at least as often as 0.6 per event, depending on the yet to be measured p + anti p production at high momentum. Comparisons are made with the first theoretical attempts to account for baryon production at these energies

  3. Charmed Bottom Baryon Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Zachary S; Detmold, William; Meinel, Stefan; Orginos, Kostas

    2014-11-01

    The spectrum of doubly and triply heavy baryons remains experimentally unexplored to a large extent. Although the detection of such heavy particle states may lie beyond the reach of exper- iments for some time, it is interesting compute this spectrum from QCD and compare results between lattice calculations and continuum theoretical models. Several lattice calculations ex- ist for both doubly and triply charmed as well as doubly and triply bottom baryons. Here, we present preliminary results from the first lattice calculation of doubly and triply heavy baryons including both charm and bottom quarks. We use domain wall fermions for 2+1 flavors (up down and strange) of sea and valence quarks, a relativistic heavy quark action for the charm quarks, and non-relativistic QCD for the heavier bottom quarks. We present preliminary results for the ground state spectrum.

  4. Photoproduction of hermaphrodite baryons

    International Nuclear Information System (INIS)

    It is shown that photoexcitation of the lightest hermaphrodite baryons is strongly suppressed from proton targets but allowed from neutrons, a result that is reminiscent of a quark model selection rule due to Moorhouse (Phys. Rev. Lett.; 16:772 (1966)). This is consistent with suggestions that the P11(1710) is the lightest q3G baryon and eliminates the possibility that the Roper resonance is dominantly an hermaphrodite state. Magnetic moments do not constrain the possibility of considerable mixing of q3G into the nucleon and delta's Fock space wavefunctions. (author)

  5. The static baryon potential

    International Nuclear Information System (INIS)

    Using state of the art lattice techniques we investigate the static baryon potential. We employ the multi-hit procedure for the time links and a variational approach to determine the ground state with sufficient accuracy that, for distances up to ∼ 1.2 fm, we can distinguish the Y- and Δ- Ansaetze for the baryonic Wilson area law. Our analysis shows that the Δ-Ansatz is favoured. This result is also supported by the gauge-invariant nucleon wave function which we measure for the first time

  6. Baryons and Chiral Symmetry

    CERN Document Server

    Liu, Keh-Fei

    2016-01-01

    The relevance of chiral symmetry in baryons is highlighted in three examples in the nucleon spectroscopy and structure. The first one is the importance of chiral dynamics in understanding the Roper resonance. The second one is the role of chiral symmetry in the lattice calculation of $\\pi N \\sigma$ term and strangeness. The third one is the role of chiral $U(1)$ anomaly in the anomalous Ward identity in evaluating the quark spin and the quark orbital angular momentum. Finally, the chiral effective theory for baryons is discussed.

  7. Cluster analysis of the organic peaks in bulk mass spectra obtained during the 2002 New England Air Quality Study with an Aerodyne aerosol mass spectrometer

    Directory of Open Access Journals (Sweden)

    C. Marcolli

    2006-06-01

    Full Text Available We applied hierarchical cluster analysis to an Aerodyne aerosol mass spectrometer (AMS bulk mass spectral dataset collected aboard the NOAA research vessel Ronald H. Brown during the 2002 New England Air Quality Study off the east coast of the United States. Emphasizing the organic peaks, the cluster analysis yielded a series of categories that are distinguishable with respect to their mass spectra and their occurrence as a function of time. The differences between the categories mainly arise from relative intensity changes rather than from the presence or absence of specific peaks. The most frequent category exhibits a strong signal at m/z 44 and represents oxidized organic matter most probably originating from both, anthropogenic as well as biogenic sources. On the basis of spectral and trace gas correlations, the second most common category with strong signals at m/z 29, 43, and 44 contains contributions from isoprene oxidation products. The third through the fifth most common categories have peak patterns characteristic of monoterpene oxidation products and were most frequently observed when air masses from monoterpene rich regions were sampled. Taken together, the second through the fifth most common categories represent as much as 5 µg/m3 organic aerosol mass – 17% of the total organic mass – that can be attributed to biogenic sources. These numbers have to be viewed as lower limits since the most common category was attributed to anthropogenic sources for this calculation. The cluster analysis was also very effective in identifying a few contaminated mass spectra that were not removed during pre-processing. This study demonstrates that hierarchical clustering is a useful tool to analyze the complex patterns of the organic peaks in bulk aerosol mass spectra from a field study.

  8. A model for net-baryon rapidity distribution

    CERN Document Server

    Alvarez-Muñiz, J; Dias de Deus, J; Santo, M C Espírito; Milhano, J G; Pimenta, M

    2009-01-01

    In nuclear collisions, a sizable fraction of the available energy is carried away by baryons. As the baryon number is conserved, the net-baryon $B-\\bar{B}$ retains information on the energy-momentum carried by the incoming nuclei. A simple and consistent model for net-baryon production in high energy proton-proton and nucleus-nucleus collisions is presented. The basic ingredients of the model are valence string formation based on standard PDFs with QCD evolution and string fragmentation via the Schwinger mechanism. The results of the model are presented and compared with data at different centre-of-mass energies and centralities, as well as with existing models. These results show that a good description of the main features of net-baryon data is possible in the framework of a simplistic model, with the advantage of making the fundamental production mechanisms manifest.

  9. A model for net-baryon rapidity distribution

    International Nuclear Information System (INIS)

    In nuclear collisions, a sizable fraction of the available energy is carried away by baryons. As baryon number is conserved, the net-baryon B- anti B retains information on the energy-momentum carried by the incoming nuclei. A simple and consistent model for net-baryon production in high energy proton-proton and nucleus-nucleus collisions is presented. The basic ingredients of the model are valence string formation based on standard PDFs with QCD evolution and string fragmentation via the Schwinger mechanism. The results of the model are presented and compared with data at different centre-of-mass energies and centralities, as well as with existing models. These results show that a good description of the main features of the net-baryon data is possible in the framework of a simplistic model, with the advantage of making the fundamental production mechanisms manifest. (orig.)

  10. New results on strange and multistrange baryon production and charged kaon production in sulphur sulphur interactions at 200 GeV/c per nucleon

    International Nuclear Information System (INIS)

    Strange and multistrange baryon and antibaryon production has been studied in sulphur sulphur interactions at 200 GeV/c per nucleon at central rapidity. Particle production ratios and transverse mass spectra are presented for Λ, Ξ-, bar Ξ and bar Ξ-. In addition preliminary results on charged kaon production are presented, and the status of identified charged particle track reconstruction using the Omega RICH is reviewed. copyright 1995 American Institute of Physics

  11. Electroproduction of light quark baryons

    International Nuclear Information System (INIS)

    The status of electromagnetic excitation of light quark (u, d) baryon states is reviewed and confronted with results of calculations within the framework of microscopic models of the baryon structure and the photon-baryon coupling. Prospects for a qualitative improvement of our knowledge in this sector using photon and electron beams at the new, intermediate energy continuous wave electron machines are discussed

  12. Upper Limit For Electron-positron Decaying To Neutral Lambda(baryon)-antineutral Lamba(baryon) Cross Section And R In The Center-of-mass Energy Range From 11.230 To 11.382 Gev

    CERN Document Server

    Dorjkhaidav, O

    2004-01-01

    We have searched for LobLo b resonance production using data taking by CLEO III detector and set an upper limit for such a cross section to be on the order of 0.05–0.10 units of R in 95% confidence level in the scanning range at Center Mass of Energies from 11.230 to 11.382 GeV. The measurement of R = σ(e+e − → hadrons)/σ(e+ e− → μ+μ− ) has been made in this scan range as well. The measured R value near Λb threshold is R = 4.01 ± 0.15

  13. Infrared Photodissociation Spectra of Mass-Selected Homoleptic Dinuclear Palladium Carbonyl Cluster Cations in the Gas Phase

    Institute of Scientific and Technical Information of China (English)

    崔洁铭; 邢小鹏; 池超贤; 王冠军; 刘智攀; 周鸣飞

    2012-01-01

    Infrared spectra of mass-selected homoleptic dinuclear palladium carbonyl cluster cations Pd2(CO)n (n=5 8) are measured via infrared photodissociation spectroscopy in the carbonyl stretching frequency region. The structures are established by comparison of the experimental spectra with simulated spectra derived from density functional calculations. The Pd2(CO)+ cation is characterized to have two weakly semibridging CO groups with C2 symmetry. The Pd2(CO)6+ and Pd2(CO)7+ cations are determined to involve one weakly semibridging CO group. The Pd2(CO)8+ cation is a CO coordination saturated cluster, which is determined to have a D2d structure with all of the carbonyl groups terminally bonded. Bonding analysis indicates that these cluster cations each has a Pd--Pd half bond. The Pd--Pd distance increases with the number of CO ligands.

  14. Cluster Analysis of the Organic Peaks in Bulk Mass Spectra Obtained During the 2002 New England Air Quality Study with an Aerodyne Aerosol Mass Spectrometer

    Directory of Open Access Journals (Sweden)

    C. Marcolli

    2006-01-01

    Full Text Available We applied hierarchical cluster analysis to an Aerodyne aerosol mass spectrometer (AMS bulk mass spectral dataset collected aboard the NOAA research vessel R. H. Brown during the 2002 New England Air Quality Study off the east coast of the United States. Emphasizing the organic peaks, the cluster analysis yielded a series of categories that are distinguishable with respect to their mass spectra and their occurrence as a function of time. The differences between the categories mainly arise from relative intensity changes rather than from the presence or absence of specific peaks. The most frequent category exhibits a strong signal at m/z 44 and represents oxidized organic matter probably originating from both anthropogenic as well as biogenic sources. On the basis of spectral and trace gas correlations, the second most common category with strong signals at m/z 29, 43, and 44 contains contributions from isoprene oxidation products. The third through the fifth most common categories have peak patterns characteristic of monoterpene oxidation products and were most frequently observed when air masses from monoterpene rich regions were sampled. Taken together, the second through the fifth most common categories represent on average 17% of the total organic mass that stems likely from biogenic sources during the ship's cruise. These numbers have to be viewed as lower limits since the most common category was attributed to anthropogenic sources for this calculation. The cluster analysis was also very effective in identifying a few contaminated mass spectra that were not removed during pre-processing. This study demonstrates that hierarchical clustering is a useful tool to analyze the complex patterns of the organic peaks in bulk aerosol mass spectra from a field study.

  15. Baryon Number Violation

    CERN Document Server

    Babu, K S; Al-Binni, U; Banerjee, S; Baxter, D V; Berezhiani, Z; Bergevin, M; Bhattacharya, S; Brice, S; Brock, R; Burgess, T W; Castellanos, L; Chattopadhyay, S; Chen, M-C; Church, E; Coppola, C E; Cowen, D F; Cowsik, R; Crabtree, J A; Davoudiasl, H; Dermisek, R; Dolgov, A; Dutta, B; Dvali, G; Ferguson, P; Perez, P Fileviez; Gabriel, T; Gal, A; Gallmeier, F; Ganezer, K S; Gogoladze, I; Golubeva, E S; Graves, V B; Greene, G; Handler, T; Hartfiel, B; Hawari, A; Heilbronn, L; Hill, J; Jaffe, D; Johnson, C; Jung, C K; Kamyshkov, Y; Kerbikov, B; Kopeliovich, B Z; Kopeliovich, V B; Korsch, W; Lachenmaier, T; Langacker, P; Liu, C-Y; Marciano, W J; Mocko, M; Mohapatra, R N; Mokhov, N; Muhrer, G; Mumm, P; Nath, P; Obayashi, Y; Okun, L; Pati, J C; Pattie, R W; Phillips, D G; Quigg, C; Raaf, J L; Raby, S; Ramberg, E; Ray, A; Roy, A; Ruggles, A; Sarkar, U; Saunders, A; Serebrov, A; Shafi, Q; Shimizu, H; Shiozawa, M; Shrock, R; Sikdar, A K; Snow, W M; Soha, A; Spanier, S; Stavenga, G C; Striganov, S; Svoboda, R; Tang, Z; Tavartkiladze, Z; Townsend, L; Tulin, S; Vainshtein, A; Van Kooten, R; Wagner, C E M; Wang, Z; Wehring, B; Wilson, R J; Wise, M; Yokoyama, M; Young, A R

    2013-01-01

    This report, prepared for the Community Planning Study - Snowmass 2013 - summarizes the theoretical motivations and the experimental efforts to search for baryon number violation, focussing on nucleon decay and neutron-antineutron oscillations. Present and future nucleon decay search experiments using large underground detectors, as well as planned neutron-antineutron oscillation search experiments with free neutron beams are highlighted.

  16. Baryons and ladders

    International Nuclear Information System (INIS)

    By formal manipulation of the QCD functional integral we arrive at a relativistic low energy effective theory of non-local color singlet mesons and baryons, which at tree level sums up ladders of effective glue exchange between constituent quarks. (orig.)

  17. Problems in baryon spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Capstick, S. [Florida State Univ., Tallahassee, FL (United States)

    1994-04-01

    Current issues and problems in the physics of ground- and excited-state baryons are considered, and are classified into those which should be resolved by CEBAF in its present form, and those which may require CEBAF to undergo an energy upgrade to 8 GeV or more. Recent theoretical developments designed to address these problems are outlined.

  18. Baryonic Dark Matter

    OpenAIRE

    Paolis, F.; Ingrosso, G.; Jetzer, Ph.; Roncadelli, M.

    1997-01-01

    Reasons supporting the idea that most of the dark matter in galaxies and clusters of galaxies is baryonic are discussed. Moreover, it is argued that most of the dark matter in galactic halos should be in the form of MACHOs and cold molecular clouds.

  19. Electromagnetic structure of octet baryons

    International Nuclear Information System (INIS)

    A numerical simulation of quenched QCD on a 24x12x12x24 lattice at β=5.9 is used to calculate the electric and magnetic form factors of the baryon octet. General forms of the baryon interpolating fields are considered. Magnetic moments, electric radii, magnetic radii, and magnetic transition moments are extracted from the form factors. The electric properties are found to be consistent with a quark-model picture involving spin-dependent forces. The lattice results for the magnetic properties show a mass and spin dependence of the effective quark moments which is not accounted for in conventional quark models. Lattice calculations underestimate the magnitude of electric radii, magnetic radii, and magnetic moments compared to experimental measurements. The finite volume of the periodic lattice may be responsible for the discrepancies. The pattern of electromagnetic radii in the lattice results are seen to be generally reproduced in the model results that are considered. The only exception is that of Ξ- which proves to be a sensitive probe of the quark dynamics. Lattice calculations indicate a positive value for the normalized square magnetic radius in Ξ- which contrasts Skyrme model results. Ratios of the magnetic moments allow a more detailed comparison with the experimental measurements. The lattice calculations are seen to better reproduce the experimental ratios than the model calculations

  20. Heavy baryons in the large Nc limit

    Science.gov (United States)

    Albertus, C.; Ruiz Arriola, E.; Fernando, I. P.; Goity, J. L.

    2015-11-01

    It is shown that in the large Nc limit heavy baryon masses can be estimated quantitatively in a 1 /Nc expansion using the Hartree approximation. The results are compared with available lattice calculations for different values of the ratio between the square root of the string tension and the heavy quark mass √{ σ} /mQ. These estimates implement important 1 /Nc corrections and assume a string tension independent of Nc. Using a potential adjusted to agree with the one obtained in lattice QCD, a variational analysis of the ground state spin averaged baryon mass is performed using Gaussian Hartree wave functions. Relativistic corrections through the quark kinetic energy are included. The results provide good estimates for the first sub-leading in 1 /Nc corrections.

  1. Magnetic Moments of Octet Baryons in Hot and Dense Nuclear Matter

    CERN Document Server

    Singh, Harpreet; Dahiya, Harleen

    2016-01-01

    We have calculated the in-medium magnetic moments of octet baryons in the presence of hot and dense symmetric nuclear matter. Effective magnetic moments of baryons have been derived from medium modified quark masses within chiral SU(3) quark mean field model.Further, for better insight of medium modification of baryonic magnetic moments, we have considered the explicit contributions from the valence as well as sea quark effects. These effects have been successful in giving the description of baryonic magnetic moments in vacuum. The magnetic moments of baryons are found to vary significantly as a function of density of nuclear medium.

  2. Experimental search of structures in missing mass spectra of B=2, T=1 system: possible evidence for narrow states

    International Nuclear Information System (INIS)

    The missing mass spectra for the transfer reaction p(3He,d)X (B=2, T=1) have been measured at Tsub(3He) = 2.7 GeV. The data show: 1) a narrow structure lying on top of an important continuum, with a mass M = 2.240+-0.005 GeV and a width GAMMAsub(1/2) = .016 +- .003 GeV; 2) a large structure with centroid location close to Msub(x) approximately equal to 2.170 +- .005 GeV and width GAMMAsub(1/2) approximately .100 +- .005 Gev

  3. Synthesis and purification of some alkyl phenanthrenes and presentation of their infrared, ultraviolet, nuclear magnetic resonance and mass spectra

    International Nuclear Information System (INIS)

    We have carried out the synthesis of: - phenanthrene - its five monomethyl derivatives - three dimethyl derivatives - two trimethyl derivatives. We have then purified these products as well as a certain number of others obtained from various sources. We have been able to obtain in the majority of cases, a purity of 99.5 per cent or over, these figures being obtained by low voltage mass spectrometry. Finally we have recorded the infrared, ultraviolet, nuclear magnetic resonance and mass spectra of these products for which an atlas has been drawn up. (author)

  4. Rapidity and Transverse Mass Spectra of Hadrons in a New Excluded-Volume Model II

    CERN Document Server

    Tiwari, S K; Singh, C P

    2012-01-01

    Remarkable success gained by various thermal and statistical approaches in describing the particle multiplicities and their ratios has emphasized the formation of a fireball consisting of chemically equilibrated hot and dense hadron gas (HG) produced in the ultrarelativistic heavy-ion collisions. In an earlier paper referred as I, we proposed a thermodynamically consistent excluded-volume model for the HG fireball and we noticed that the model gives a suitable description for various properties of multiparticle production and their ratios in the entire range of temperatures and baryon densities. Furthermore, a numerical calculation indicates that the model respects causality and the values of the transport coefficients (such as shear viscosity to entropy ($\\eta/s$) ratio, and the speed of sound etc.) suitably match with the predictions of other HG models. The aim in this paper is to obtain the variations of freeze-out volume in a slice of unit rapidity i.e. $dV/dy$ as well as total volume of the fireball with...

  5. Constraining warm dark matter with cosmic shear power spectra

    International Nuclear Information System (INIS)

    We investigate potential constraints from cosmic shear on the dark matter particle mass, assuming all dark matter is made up of light thermal relic particles. Given the theoretical uncertainties involved in making cosmological predictions in such warm dark matter scenarios we use analytical fits to linear warm dark matter power spectra and compare (i) the halo model using a mass function evaluated from these linear power spectra and (ii) an analytical fit to the non-linear evolution of the linear power spectra. We optimistically ignore the competing effect of baryons for this work. We find approach (ii) to be conservative compared to approach (i). We evaluate cosmological constraints using these methods, marginalising over four other cosmological parameters. Using the more conservative method we find that a Euclid-like weak lensing survey together with constraints from the Planck cosmic microwave background mission primary anisotropies could achieve a lower limit on the particle mass of 2.5 keV

  6. A Monte Carlo approach for assessing the specificity of protein oligomers observed in nano-electrospray mass spectra

    Science.gov (United States)

    Lane, Laura A.; Ruotolo, Brandon T.; Robinson, Carol V.; Favrin, Giorgio; Benesch, Justin L. P.

    2009-06-01

    Nano-electrospray mass spectrometry is an emerging approach for studying the architecture and dynamics of complex oligomeric proteins. The analysis of such species can, however, be hindered by [`]non-specific' protein-protein associations which arise as a result of the electrospray method. To understand the formation of specific versus non-specific protein oligomers detected by mass spectrometry we have developed a simple and rapid computational approach. This Monte Carlo algorithm characterizes the occupancy of protein species in the last offspring droplets created by the nano-electrospray process. As such it enables us to assess whether oligomers detected in mass spectra reflect solution populations, or instead are the result of associations during droplet fission and evaporation. We have trained and validated this method on three model protein complexes which are not known to form higher order oligomers, and one which has a tendency to self-associate in solution in a concentration dependent manner. We have then compared predictions of droplet occupancy to abundances obtained from mass spectra for the tetrameric amyloid-related protein transthyretin, which can cause cardiomyopathy and polyneuropathy in humans. Interestingly, when such comparisons were made for wild-type transthyretin we were able to observe a propensity for the protein to form specific oligomers larger than the tetramer. In contrast, the tendency for the leucine-55-proline variant to form such oligomers was considerably reduced. We contemplate the significance of these specific higher order wild-type oligomers, and absence of such species in the variant, on the pathway of amyloid formation in transthyretin. More generally this easy-to-implement computational approach promises to improve our ability to identify oligomers of biological significance within the mass spectra of heterogenous protein complexes.

  7. Shell Model Analysis of Ξ-Hypernuclei Spectra for Mass A=12 and A=16

    Institute of Scientific and Technical Information of China (English)

    TAN Yu-Hong; LUO Yan-An; NING Ping-Zhi; CAI Chong-Hai

    2000-01-01

    The excitation spectra for(12Ξ_Be) and (1Ξ6_C) are obtained in the frame of a shell model. The experimental values of the ground state binding energies of the Ξ- hyperon in (12Ξ_Be) and (1Ξ6_ C) are used to determine the well depth of the Ξ-nucleus potential. The information on the residual interaction is emphasized. It is found that the residual interaction does not have much effect on the spectra of the Ξ--hypernucleus.

  8. Three body resonances in two meson-one baryon systems

    OpenAIRE

    Martínez Torres, Alberto; Khemchandani, K. P.; Oset Báguena, Eulogio

    2007-01-01

    We report four $\\Sigma$'s and three $\\Lambda$'s, in the 1500 - 1800 MeV region, as two meson - one baryon S-wave $(1/2)^+$ resonances. We solve Faddeev equations in the coupled channel approach. The invariant mass of one of the meson-baryon pairs and that of the three particles have been varied and peaks in the squared three body $T$-matrix have been found very close to the existing $S$ = -1, $J^P= 1/2^+$ low lying baryon resonances. The input two-body $t$-matrices for meson-meson and meson-b...

  9. Splitting Mass Spectra and Muon g-2 in Higgs-Anomaly Mediation

    CERN Document Server

    Yin, Wen

    2016-01-01

    We propose a scenario where only the Higgs multiplets have direct couplings to a supersymmetry (SUSY) breaking sector. The standard model matter multiplets as well as the gauge multiples are sequestered from the SUSY breaking sector; therefore, their masses arise via anomaly mediation at the high energy scale with a gravitino mass of $\\sim$100 TeV. Due to renormalization group running effects from the Higgs soft masses, the masses of the third generation sfermions become O(10) TeV at the low energy scale, while the first and second generation sfermion masses are O(0.1-1) TeV, avoiding the tachyonic slepton problem and flavor changing neutral current problem. With the splitting mass spectrum, the muon g-2 anomaly is explained consistently with the observed Higgs boson mass of 125 GeV. Moreover, the third generation Yukawa couplings are expected to be unified in some regions.

  10. Manifestation of Conformal Symmetry in the Light Flavor Baryon Sector

    CERN Document Server

    Kirchbach, M

    2010-01-01

    On the AdS_5 cone, conformally compactified to R^1xS^3, a quark-diquark model of light flavor baryons is developed. The system on this manifold is decribed in terms of a scalar conformal equation, gauged by the field of a D3 brane whose transversal dimensions have been conformally warpped over R^1xS^3. Such a system does not result exactly conformally invariant because the gauge potential slightly modifies the conformal centrifugal barrier of the free geodesic motion. Thanks to this, the model describes the correct mass ordering in the P11-S11 pairs through the N spectrum as a combined effect of conformal symmetry breaking, on the one side, and a parity change of the diquark from a scalar at low masses, to a pseudoscalar at higher masses, on the other. We calculate the number of resonances with masses below 2500 MeV needed for the completeness of the above scheme and find a total of 32 "missing" nucleon and Delta states. Their absence or presence in the respective spectra relates to the degree to which confor...

  11. Applying 'Sequential Windowed Acquisition of All Theoretical Fragment Ion Mass Spectra' (SWATH) for systematic toxicological analysis with liquid chromatography-high-resolution tandem mass spectrometry.

    Science.gov (United States)

    Arnhard, Kathrin; Gottschall, Anna; Pitterl, Florian; Oberacher, Herbert

    2015-01-01

    Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become an indispensable analytical technique in clinical and forensic toxicology for detection and identification of potentially toxic or harmful compounds. Particularly, non-target LC-MS/MS assays enable extensive and universal screening requested in systematic toxicological analysis. An integral part of the identification process is the generation of information-rich product ion spectra which can be searched against libraries of reference mass spectra. Usually, 'data-dependent acquisition' (DDA) strategies are applied for automated data acquisition. In this study, the 'data-independent acquisition' (DIA) method 'Sequential Windowed Acquisition of All Theoretical Fragment Ion Mass Spectra' (SWATH) was combined with LC-MS/MS on a quadrupole-quadrupole-time-of-flight (QqTOF) instrument for acquiring informative high-resolution tandem mass spectra. SWATH performs data-independent fragmentation of all precursor ions entering the mass spectrometer in 21m/z isolation windows. The whole m/z range of interest is covered by continuous stepping of the isolation window. This allows numerous repeat analyses of each window during the elution of a single chromatographic peak and results in a complete fragment ion map of the sample. Compounds and samples typically encountered in forensic casework were used to assess performance characteristics of LC-MS/MS with SWATH. Our experiments clearly revealed that SWATH is a sensitive and specific identification technique. SWATH is capable of identifying more compounds at lower concentration levels than DDA does. The dynamic range of SWATH was estimated to be three orders of magnitude. Furthermore, the >600,000 SWATH spectra matched led to only 408 incorrect calls (false positive rate = 0.06 %). Deconvolution of generated ion maps was found to be essential for unravelling the full identification power of LC-MS/MS with SWATH. With the available software, however, only semi

  12. The electroweak axion, dark energy, inflation and baryonic matter

    International Nuclear Information System (INIS)

    In a previous paper [1], the standard model was generalized to include an electroweak axion which carries baryon plus lepton number, B + L. It was shown that such a model naturally gives the observed value of the dark energy, if the scale of explicit baryon number violation A was chosen to be of the order of the Planck mass. In this paper, we consider the effect of the modulus of the axion field. Such a field must condense in order to generate the standard Goldstone boson associated with the phase of the axion field. This condensation breaks baryon number. We argue that this modulus might be associated with inflation. If an additional B − L violating scalar is introduced with a mass similar to that of the modulus of the axion field, we argue that decays of particles associated with this field might generate an acceptable baryon asymmetry

  13. Charmed baryon search in hadronic interactions with 150 GeV/c incident protons

    International Nuclear Information System (INIS)

    The hadronic associated production of charmed particles in pBe-interactions at 150 GeV incident momentum is studied. The experiment exploits the fact that charmed particles are produced in pairs and that one of the pair can decay with a single electron in the final state. This electron is used as a tag on charmed particle production. An elaborate system has been developed to suppress the background due to electrons from photon conversion or from the Dalitz decay of mesons. Measuring instruments and data analysis are described. The author reviews the history of the charmed quark and the experimental status of charm observation. The emphasis is put on the observation and production mechanisms of charmed baryons. Finally he presents the results from his study of charmed baryon production. The measurement of known resonances and the capability of the experimental set-up to measure the Λsub(c)+ is discussed. From the absence of a signal in the mass spectra of three different decay channels of the Λsub(c)+ he derives a 90 percent C.L. upper limit of (57 +- 5) μb for Λsub(c)+D production. For the pK-π+ decay channel he applied several kinematical Λsub(c)+D production models. The results are compared with those from other experiments studying the hadronic production of charmed baryons at approximately the same energy of 16.8 GeV. (Auth.)

  14. Meson/baryon/tetraquark supersymmetry from superconformal algebra and light-front holography

    Science.gov (United States)

    Brodsky, Stanley J.; de Téramond, Guy F.; Dosch, Hans Günter; Lorcé, Cédric

    2016-07-01

    Superconformal algebra leads to remarkable connections between the masses of mesons and baryons of the same parity — supersymmetric relations between the bosonic and fermionic bound states of QCD. Supercharges connect the mesonic eigenstates to their baryonic superpartners, where the mesons have internal angular momentum one unit higher than the baryons: LM = LB + 1. The dynamics of the superpartner hadrons also match; for example, the power-law fall-off of the form factors are the same for the mesonic and baryonic superpartners, in agreement with twist counting rules. An effective supersymmetric light-front Hamiltonian for hadrons composed of light quarks can be constructed by embedding superconformal quantum mechanics into AdS space. This procedure also generates a spin-spin interaction between the hadronic constituents. A specific breaking of conformal symmetry inside the graded algebra determines a unique quark-confining light-front potential for light hadrons in agreement with the soft-wall AdS/QCD approach and light-front holography. Only one mass parameter λ appears; it sets the confinement mass scale, a universal value for the slope of all Regge trajectories, the nonzero mass of the proton and other hadrons in the chiral limit, as well as the length scale which underlies their structure. The mass for the pion eigenstate vanishes in the chiral limit. When one includes the constituent quark masses using the Feynman-Hellman theorem, the predictions are consistent with the empirical features of the light-quark hadronic spectra. Our analysis can be consistently applied to the excitation spectra of the π, ρ, K, K∗ and ϕ meson families as well as to the N, Δ, Λ, Σ, Σ∗, Ξ and Ξ∗ baryons. We also predict the existence of tetraquarks which are degenerate in mass with baryons with the same angular momentum. The mass-squared of the light hadrons can be expressed in a universal and frame-independent decomposition of contributions from the constituent

  15. On gauged Baryon and Lepton numbers

    International Nuclear Information System (INIS)

    The observation that Baryon number and Lepton number are conserved in nature provides strong motivation for associating gauge symmetries to these conserved numbers. This endeavor requires that the gauge group of electroweak interactions be extended from SU(2)L X U(1)Y to SU(2)L X U(1)R X U(1)Lepton where U(1)R couples only to the right-handed quarks and leptons. If it furthur postulated that right-handed currents exist on par with the left-handed ones, then the full electroweak symmetry is SU(2)L X SU(2)R X U(1)Baryon X U(1)Lepton. The SU(2)L X SU(2)R X U(1)Baryon X U(1)Lepton model is described in some detail. The triangle anomalies of the three families of quarks and leptons in the model are cancelled invoking leptoquark matter which is new fermionic matter that carries baryon as well as lepton numbers. In addition to the standard neutral boson (Z degree), the theory predicts two neutral gauge bosons with mass lower bounds of 120 GeV and 210 GeV which makes these particles prospective candidates for production at LEP, the TEVATRON and the SSC

  16. The Mass-Metallicity Relation with the Direct Method on Stacked Spectra of SDSS Galaxies

    CERN Document Server

    Andrews, Brett H

    2012-01-01

    The relation between galaxy stellar mass and gas-phase metallicity is a sensitive diagnostic of the main processes that drive galaxy evolution, namely cosmological gas inflow, metal production in stars, and gas outflow via galactic winds. We employed the direct method to measure the metallicities of ~200,000 star-forming galaxies from the SDSS that were stacked in bins of (1) stellar mass and (2) both stellar mass and star formation rate (SFR) to significantly enhance the signal-to-noise ratio of the weak [O III] 4363 and [O II] 7320, 7330 auroral lines required to apply the direct method. These metallicity measurements span three decades in stellar mass from log(Mstar/Msun) = 7.4--10.5, which allows the direct method mass--metallicity relation to simultaneously capture the high-mass turnover and extend a full decade lower in mass than previous studies that employed more uncertain strong line methods. The direct method mass-metallicity relation rises steeply at low mass (O/H ~ Mstar^{1/2}) until it turns over...

  17. CP Violating Baryon Oscillations

    OpenAIRE

    McKeen, David; Nelson, Ann E.

    2015-01-01

    We analyze neutron-antineutron oscillation in detail, developing a Hamiltonian describing the system in the presence of electromagnetic fields. While magnetic fields can couple states of different spin, we show that, because of Fermi statistics, this coupling of different spin states does not involve baryon-number--changing transitions and, therefore, a two-state analysis ignoring spin is sufficient even in the presence of electromagnetic fields. We also enumerate the conditions necessary for...

  18. Reconstructing baryon oscillations

    OpenAIRE

    Noh, Yookyung; White, Martin; Padmanabhan, Nikhil

    2009-01-01

    The baryon acoustic oscillation (BAO) method for constraining the expansion history is adversely affected by non-linear structure formation, which washes out the correlation function peak created at decoupling. To increase the constraining power of low z BAO experiments, it has been proposed that one use the observed distribution of galaxies to "reconstruct'' the acoustic peak. Recently Padmanabhan, White and Cohn provided an analytic formalism for understanding how reconstruction works withi...

  19. Doubly heavy spin-1/2 baryon spectrum in QCD

    International Nuclear Information System (INIS)

    We calculate the mass and residue of the heavy spin-1/2 baryons containing two heavy b or c quarks in the framework of QCD sum rules. We use the most general form of the interpolating current in its symmetric and anti-symmetric forms with respect to the exchange of heavy quarks, to calculate the two-point correlation functions describing the baryons under consideration. A comparison of the obtained results with existing predictions from various approaches is also made.

  20. New Paradigm for Baryon and Lepton Number Violation

    OpenAIRE

    Perez, Pavel Fileviez

    2015-01-01

    The possible discovery of proton decay, neutron-antineutron oscillation, neutrinoless beta decay in low energy experiments, and exotic signals related to the violation of the baryon and lepton numbers at collider experiments will change our understanding of the conservation of fundamental symmetries in nature. In this review we discuss the rare processes due to the existence of baryon and lepton number violating interactions. The simplest grand unified theories and the neutrino mass generatio...

  1. Galaxy And Mass Assembly (GAMA) Blended Spectra Catalog: Strong Galaxy-Galaxy Lens and Occulting Galaxy Pair Candidates

    CERN Document Server

    Holwerda, B W; Alpaslan, M; Bauer, A; Bland-Hawthorn, J; Brough, S; Brown, M J I; Cluver, M E; Conselice, C; Driver, S P; Hopkins, A M; Jones, D H; Lopez-Sanchez, A R; Loveday, J; Meyer, M J; Moffett, A

    2015-01-01

    We present the catalogue of blended galaxy spectra from the Galaxy And Mass Assembly (GAMA) survey. These are cases where light from two galaxies are significantly detected in a single GAMA fibre. Galaxy pairs identified from their blended spectrum fall into two principal classes: they are either strong lenses, a passive galaxy lensing an emission-line galaxy; or occulting galaxies, serendipitous overlaps of two galaxies, of any type. Blended spectra can thus be used to reliably identify strong lenses for follow-up observations (high resolution imaging) and occulting pairs, especially those that are a late-type partly obscuring an early-type galaxy which are of interest for the study of dust content of spiral and irregular galaxies. The GAMA survey setup and its autoz automated redshift determination were used to identify candidate blended galaxy spectra from the cross-correlation peaks. We identify 280 blended spectra with a minimum velocity separation of 600 km/s, of which 104 are lens pair candidates, 71 e...

  2. SpectraMiner, an interactive data mining and visualization software for single particle mass spectroscopy: A laboratory test case

    Science.gov (United States)

    Zelenyuk, Alla; Imre, Dan; Cai, Yong; Mueller, Klaus; Han, Yiping; Imrich, Peter

    2006-12-01

    Single particle mass spectrometers are sophisticated instruments designed to measure the sizes and compositions of a wide range of individual particles in situ, in real-time. They characterize hundreds of thousands or millions of particles, generating vast amounts of rich and complex data, the proper mining of which requires dedicated state of the art tools. The analysis of individual particle mass spectra is particularly difficult because of their high dimensionality--each data point, representing a single particle, includes the 450 mass spectral peak intensities, particle size, and time of detection. The first step is to organize the data; a process typically accomplished by grouping particles of similar attributes. Since the common assumption is that the data should be reduced to become manageable, they are typically classified into a small number of clusters (~10), each of which is represented by an average/representative spectrum. Our approach is quite different. We have developed a data mining and visualization software package we call SpectraMiner that makes it possible to handle hundreds of clusters, limiting loss of information and thus overcoming the boundaries set by traditional statistical data analysis approaches. Data, which often include over 1 million particle spectra, are organized using K-mean clustering algorithm. The clusters are merged into nodes by sequentially combining similar clusters. The final structure is displayed in a hierarchical dynamical tree or circular dendogram. This interactive dendogram is the visual interface that allows for real-time data exploration and mining. Clicking on any of the clusters/nodes in the dendogram reveals the detailed information about the particles that reside at that position. At each step the scientist is in control of the level of detail and the visualization format, rapidly switching between them while running the program on a PC. Here we present a study that puts the classification aspect of Spectra

  3. Two Baryons with Twisted Boundary Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Briceno, Raul [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Davoudi, Zohreh [Univ. of Washington, Seattle, WA (United States) and Institute for Nuclear Theory, Seattle, WA (United States); Luu, Thomas [Lawrence Livermore National Laboratory, Livermore, CA (United States); Savage, Martin [Univ. of Washington, Seattle, WA (United States) and Institute for Nuclear Theory, Seattle, WA (United States)

    2014-04-01

    The quantization condition for two particle systems with arbitrary number of two-body open coupled-channels, spin and masses in a finite cubic volume is presented. The condition presented is in agreement with all previous studies of two-body systems in a finite volume. The result is fully relativistic and holds for all momenta below inelastic thresholds and is exact up to exponential volume corrections that are governed by m{sub {pi}} L, where m{sub {pi}} is the pion mass and L is the spatial extent of my box. Its implication for the studies of coupled-channel baryon-baryon systems is discussed, and the necessary tools for implementing the formalism are review.

  4. Selectivity of solid phase extraction of freshwater dissolved organic matter and its effect on ultrahigh resolution mass spectra.

    Science.gov (United States)

    Raeke, Julia; Lechtenfeld, Oliver J; Wagner, Martin; Herzsprung, Peter; Reemtsma, Thorsten

    2016-07-13

    Solid phase extraction (SPE) is often used for enrichment and clean-up prior to analysis of dissolved organic matter (DOM) by electrospray ionization (ESI) coupled to ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). It is generally accepted that extraction by SPE is not quantitative with respect to carbon concentration. However, little information is available on the selectivity of different SPE sorbents and the resulting effect for the acquired DOM mass spectra. Freshwater samples were extracted by the widely used PPL, HLB and C18 sorbents and the molecular composition and size distribution of the DOM in the extracts and in the permeates was compared to the original sample. Dissolved organic carbon (DOC) recoveries ranged between 20% and 65% for the three tested SPE sorbents. Size-exclusion chromatography coupled to organic carbon detection (SEC-OCD) revealed that limited recovery by PPL and HLB was primarily due to incomplete elution of a fraction of apparent high molecular weight from the solid phase. In contrast, incomplete retention on the solid phase, mainly observed for the C18 cartridge, was attributed to a fraction of low molecular weight. The FT-ICR mass spectra of the original sample and the SPE extracts did not differ significantly in their molecular weight distribution, but they showed sorbent specific differences in the degree of oxygenation and saturation. We concluded that the selective enrichment of freshwater DOM by SPE is less critical for subsequent FT-ICR MS analysis, because those fractions that are not sufficiently recovered have comparatively small effects on the mass spectra. This was confirmed by the extraction of model compounds, showing that very polar and small molecules are poorly extracted, but also have a low response in ESI-MS. Of the three tested SPE cartridges the PPL material offered the best properties for DOM enrichment for subsequent FT-ICR MS analysis as it minimizes too strong and

  5. Strangeness S = -3 and -4 baryon-baryon interactions in chiral EFT

    International Nuclear Information System (INIS)

    I report on recent progress in the description of baryon-baryon systems within chiral effective field theory. In particular, I discuss results for the strangeness S = -3 to -4 baryon-baryon systems, obtained to leading order.

  6. High statistics analysis using anisotropic clover lattices: (III) Baryon-baryon interactions

    Energy Technology Data Exchange (ETDEWEB)

    Beane, S; Detmold, W; Lin, H; Luu, T; Orginos, K; Savage, M; Torok, A; Walker-Loud, A

    2010-01-19

    Low-energy baryon-baryon interactions are calculated in a high-statistics lattice QCD study on a single ensemble of anisotropic clover gauge-field configurations at a pion mass of m{sub {pi}} {approx} 390 MeV, a spatial volume of L{sup 3} {approx} (2.5 fm){sup 3}, and a spatial lattice spacing of b {approx} 0.123 fm. Luescher's method is used to extract nucleon-nucleon, hyperon-nucleon and hyperon-hyperon scattering phase shifts at one momentum from the one- and two-baryon ground-state energies in the lattice volume. The isospin-3/2 N{Sigma} interactions are found to be highly spin-dependent, and the interaction in the {sup 3}S{sub 1} channel is found to be strong. In contrast, the N{Lambda} interactions are found to be spin-independent, within the uncertainties of the calculation, consistent with the absence of one-pion-exchange. The only channel for which a negative energy-shift is found is {Lambda}{Lambda}, indicating that the {Lambda}{Lambda} interaction is attractive, as anticipated from model-dependent discussions regarding the H-dibaryon. The NN scattering lengths are found to be small, clearly indicating the absence of any fine-tuning in the NN-sector at this pion mass. This is consistent with our previous Lattice QCD calculation of NN interactions. The behavior of the signal-to-noise ratio in the baryon-baryon correlation functions, and in the ratio of correlation functions that yields the ground-state energy splitting is explored. In particular, focus is placed on the window of time slices for which the signal-to-noise ratio does not degrade exponentially, as this provides the opportunity to extract quantitative information about multi-baryon systems.

  7. Mapping chiral symmetry breaking in the excited baryon spectrum

    CERN Document Server

    Bicudo, Pedro; Llanes-Estrada, Felipe J; Van Cauteren, Tim

    2016-01-01

    We study the conjectured "Insensitivity to Chiral Symmetry Breaking" in the highly excited light baryon spectrum. While the experimental spectrum is being measured at JLab and CBELSA/TAPS, this insensitivity remains to be computed theoretically in detail. As the only existing option to have both confinement, highly excited states and chiral symmetry, we adopt the truncated Coulomb gauge formulation of QCD, considering a linearly confining Coulomb term. Adopting a systematic and numerically intensive variational treatment up to 12 harmonic oscillator shells we are able to access several angular and radial excitations. We compute both the excited spectra of $I=1/2$ and $I=3/2$ baryons, up to large spin $J=13/2$, and study in detail the proposed chiral multiplets. While the static-light and light-light spectra clearly show chiral symmetry restoration high in the spectrum, the realization of chiral symmetry is more complicated in the baryon spectrum than earlier expected.

  8. Identification of Time-of-Flight spectra for Isochronous Mass Measurements

    Institute of Scientific and Technical Information of China (English)

    SUN Bao-Hua; H. Geissel; M. Hausmann; C. Kozhuharov; R. Kn(o)bel; Yu.A. Litvinov; MENG Jie; Z. Patyk; T. Radon; C. Scheidenberger

    2009-01-01

    The Isochronous Mass Spectrometry (IMS) developed at GSI is a very efficient method for direct mass measurements of short-lived nuclides. By taking a recent IMS experiment as an example, the identification procedure of the Time-of-Flight (TOF) spectrum measured in this experiment is discussed.

  9. Cosmological perturbation theory for baryons and dark matter I. One-loop corrections in the RPT framework

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, Gabor [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Zurich Univ. (Switzerland). Inst. for Theoretical Physics; Smith, Robert E. [Zurich Univ. (Switzerland). Inst. for Theoretical Physics

    2009-10-15

    Baryonic Acoustic Oscillation (BAO) features are amplified for baryon and slightly damped for CDM spectra. If we compare the total matter power spectra in the 2- and 1-component fluid approaches, then we find excellent agreement, with deviations being < 0.5% throughout the evolution. Consequences: high precision modeling of the large-scale distribution of baryons in the Universe can not be achieved through an effective mean-mass 1-component fluid approximation; detection significance of BAO will be amplified in probes that study baryonic matter, relative to probes that study the CDM or total mass only. The CDM distribution can be modeled accurately at late times and the total matter at all times. This is good news for probes that are sensitive to the total mass, such as gravitational weak lensing as existing modeling techniques are good enough. Lastly, we identify an analytic approximation that greatly simplifies the evaluation of the full PT expressions, and it is better than < 1% over the full range of scales and times considered. (orig.)

  10. Clustering, Anisotropy, Spectra of Ultra High Energy Cosmic Ray Finger-prints of Relic Neutrinos Masses in Dark Halos

    CERN Document Server

    Fargion, D; De Sanctis-Lucentini, P G; Troia, C D; Fargion, Daniele; Grossi, Marco

    2001-01-01

    The Ultra High Energy Cosmic Ray UHECR, by UHE neutrino-relic neutrino Z showering in Hot Dark Halos HDM, should exhibits an energy spectra and an anisotropy reflecting (also) the relic neutrino masses and their hierarchical HDM halo clustering. A twin light neutrino mass splitting may reflect to twin Z resonance and into a complex UHECR spectra modulation, a twin bump, at the edge at highest GZK energy cut-off. Each possible neutrino mass associates a characteristic dark halo size (galactic, local, Super Cluster) and its local anisotropy due to our peculiar position within that dark matter distribution. A neutrino HDM halo around a Mpc will allow to the UHECR neutron secondary component at E_n> 10^{20} eV (due to Z decay) to arise playing a role comparable with the charged p- anti{p} ones. Their un-deflected n-anti{n} (or decayed p-anti{p}) flight is shorter leading to a prompt and hard UHECR trace pointing toward the original UHECR source direction. The direct p -anti{p} pairs are split and spread by random...

  11. Chiral dynamics and baryon resonances

    OpenAIRE

    Hyodo, Tetsuo

    2010-01-01

    The structure of baryon resonance in coupled-channel meson-baryon scattering is studied from the viewpoint of chiral dynamics. The meson-baryon scattering amplitude can be successfully described together with the properties of the resonance in the scattering, by implementing the unitarity condition for the amplitude whose low energy structure is constrained by chiral theorem. Recently, there have been a major progress in the study of the structure of the resonance in chiral dynamics. We revie...

  12. COMPARISON OF SIMCA PATTERN RECOGNITION & LIBRARY SEARCH IDENTIFICATION OF HAZARDOUS COMPOUNDS FROM MASS SPECTRA

    Science.gov (United States)

    SIMCA pattern recognition methods have been applied to mass spectral data from a target list of hazardous chemicals. cheme has been proposed for classification and identification of five classes of compounds including aromatics, chlorocarbons, bromocarbons, hydrocarbons, and poly...

  13. COMPARISON OF SIMCA PATTERN RECOGNITION AND LIBRARY SEARCH IDENTIFICATION OF HAZARDOUS COMPOUNDS FROM MASS SPECTRA

    Science.gov (United States)

    SIMCA pattern recognition methods have been applied to mass spectral data from a target list of hazardous chemicals. cheme has been proposed for classification and identification of five classes of compounds including aromatics, chlorocarbons, bromocarbons, hydrocarbons, and poly...

  14. Production of resonances in a thermal model: invariant-mass spectra and balance functions

    OpenAIRE

    Florkowski, W.; Broniowski, W.; Bozek, P.

    2004-01-01

    We present a calculation of the pi+ pi- invariant-mass correlations and the pion balance functions in the single-freeze-out model. A satisfactory agreement with the data for Au+Au collisions is found.

  15. Proteomics of Soil and Sediment: Protein Identification by De Novo Sequencing of Mass Spectra Complements Traditional Database Searching

    Science.gov (United States)

    Miller, S.; Rizzo, A. I.; Waldbauer, J.

    2015-12-01

    Proteomics has the potential to elucidate the metabolic pathways and taxa responsible for in situ biogeochemical transformations. However, low rates of protein identification from high resolution mass spectra have been a barrier to the development of proteomics in complex environmental samples. Much of the difficulty lies in the computational challenge of linking mass spectra to their corresponding proteins. Traditional database search methods for matching peptide sequences to mass spectra are often inadequate due to the complexity of environmental proteomes and the large database search space, as we demonstrate with soil and sediment proteomes generated via a range of extraction methods. One alternative to traditional database searching is de novo sequencing, which identifies peptide sequences without the need for a database. BLAST can then be used to match de novo sequences to similar genetic sequences. Assigning confidence to putative identifications has been one hurdle for the implementation of de novo sequencing. We found that accurate de novo sequences can be screened by quality score and length. Screening criteria are verified by comparing the results of de novo sequencing and traditional database searching for well-characterized proteomes from simple biological systems. The BLAST hits of screened sequences are interrogated for taxonomic and functional information. We applied de novo sequencing to organic topsoil and marine sediment proteomes. Peak-rich proteomes, which can result from various extraction techniques, yield thousands of high-confidence protein identifications, an improvement over previous proteomic studies of soil and sediment. User-friendly software tools for de novo metaproteomics analysis have been developed. This "De Novo Analysis" Pipeline is also a faster method of data analysis than constructing a tailored sequence database for traditional database searching.

  16. Baryon number transport at LHC energies with the ALICE experiment

    NARCIS (Netherlands)

    Christakoglou, P.; Botje, M.A.J.; Mischke, A.; van Leeuwen, M.

    2009-01-01

    Particle yields along with the ratios of particle production in hadronic interactions are important indicators of the collision dynamics. In particular, the detailed analysis of the baryon spectra as well as that of p¯/p and L¯ /L ratios are of great importance since they allow to determine the carr

  17. Synthesis of nanoparticles in helium droplets—A characterization comparing mass-spectra and electron microscopy data

    Energy Technology Data Exchange (ETDEWEB)

    Thaler, Philipp; Volk, Alexander; Lackner, Florian; Steurer, Johannes; Schnedlitz, Martin; Ernst, Wolfgang E., E-mail: wolfgang.ernst@tugraz.at [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz (Austria); Knez, Daniel; Haberfehlner, Georg [Institute for Electron Microscopy and Nanoanalysis & Graz Centre for Electron Microscopy, TU Graz, Steyrergasse 17, A-8010 Graz (Austria)

    2015-10-07

    Micrometer sized helium droplets provide an extraordinary environment for the growth of nanoparticles. The method promises great potential for the preparation of core-shell particles as well as one-dimensional nanostructures, which agglomerate along quantum vortices, without involving solvents, ligands, or additives. Using a new apparatus, which enables us to record mass spectra of heavy dopant clusters (>10{sup 4} amu) and to produce samples for transmission electron microscopy simultaneously, we synthesize bare and bimetallic nanoparticles consisting of various materials (Au, Ni, Cr, and Ag). We present a systematical study of the growth process of clusters and nanoparticles inside the helium droplets, which can be described with a simple theoretical model.

  18. Synthesis of nanoparticles in helium droplets—A characterization comparing mass-spectra and electron microscopy data

    International Nuclear Information System (INIS)

    Micrometer sized helium droplets provide an extraordinary environment for the growth of nanoparticles. The method promises great potential for the preparation of core-shell particles as well as one-dimensional nanostructures, which agglomerate along quantum vortices, without involving solvents, ligands, or additives. Using a new apparatus, which enables us to record mass spectra of heavy dopant clusters (>104 amu) and to produce samples for transmission electron microscopy simultaneously, we synthesize bare and bimetallic nanoparticles consisting of various materials (Au, Ni, Cr, and Ag). We present a systematical study of the growth process of clusters and nanoparticles inside the helium droplets, which can be described with a simple theoretical model

  19. Formation of η-mesic nuclei by (π, N) reaction and chiral symmetry for baryons

    International Nuclear Information System (INIS)

    We calculate formation spectra of η-nucleus systems in (π, N) reactions with nuclear targets, which can be performed at existing and/or forthcoming facilities, including J-PARC, in order to investigate η-nucleus interactions. Based on the N*(1535) dominance in the ηN system, η-mesic nuclei are suitable systems for study of in-medium properties of the N*(1535) baryon resonance, such as reduction of the mass difference of N and N* in nuclear medium, which affects level structure of the η and N*-hole modes. We find that clear information on the in-medium N*- and η-nucleus interactions can be obtained through the formation spectra of the η-mesic nuclei. (author)

  20. A unified explanation for the supernova rate-galaxy mass dependency based on supernovae discovered in Sloan galaxy spectra

    CERN Document Server

    Graur, Or; Modjaz, Maryam

    2014-01-01

    Using a method to discover and classify supernovae (SNe) in galaxy spectra, we detect 91 Type Ia SNe (SNe Ia) and 16 Type II SNe (SNe II) among ~740,000 galaxies of all types and ~215,000 star-forming galaxies without active galactic nuclei, respectively, in Data Release 9 of the Sloan Digital Sky Survey. Of these SNe, 22 SNe Ia and 8 SNe II are new discoveries reported here for the first time. We use our SN samples to measure SN rates per unit mass as a function of galaxy stellar mass, star-formation rate (SFR), and specific SFR (sSFR), as derived by the MPA-JHU Galspec pipeline. We confirm the rate-mass correlations, first discovered by the Lick Observatory Supernova Search, for both SNe Ia and SNe II at median redshifts of ~0.1 and ~0.075, respectively. The mass-normalized SN Ia and SN II rates, averaged over all masses and redshifts in their respective galaxy samples, are 0.10 +/- 0.01 (stat) +/- 0.01 (sys) X 10^-12 Msol^-1 yr^-1 and 0.52 +0.16 -0.13 (stat) +0.02 -0.05 (sys) X 10^-12 Msol^-1 yr^-1, respec...

  1. The Baryon Content of Groups and Clusters of Galaxies

    CERN Document Server

    Roussel, H; Blanchard, A

    2000-01-01

    We have analyzed the properties of a sample of 33 groups and clusters of galaxies and examine the baryon content to check for trends over a decade in temperature down to 1 keV. We examine the relative contribution of galaxies and ICM to baryons in clusters through the gas-to-stellar mass ratio and find that the typical stellar contribution to the baryonic mass is between 5 and 20%. This ratio is found to be roughly independent of temperature. Therefore, we do not confirm the trend of increasing gas-to-stellar mass ratio with increasing temperature as previously claimed. We also determine distribution of the baryon fraction with the density contrast. Virial masses are estimated from two different mass estimators: one based on the isothermal hydrostatic equation (IHE), the other based on scaling law models (SLM). Comparing the two methods, we find that SLM lead to less dispersed baryon fractions over all density contrasts and that the derived mean absolute valuesare significantly lower than IHE mean values. We ...

  2. Factorization for Jet Radius Logarithms in Jet Mass Spectra at the LHC

    CERN Document Server

    Kolodrubetz, Daniel W; Stewart, Iain W; Tackmann, Frank J; Waalewijn, Wouter J

    2016-01-01

    To predict the jet mass spectrum at a hadron collider it is crucial to account for the resummation of logarithms between the transverse momentum of the jet and its invariant mass $m_J$. For small jet areas there are additional large logarithms of the jet radius $R$, which affect the convergence of the perturbative series. We present an analytic framework for exclusive jet production at the LHC which gives a complete description of the jet mass spectrum including realistic jet algorithms and jet vetoes. It factorizes the scales associated with $m_J$, $R$, and the jet veto, enabling in addition the systematic resummation of jet radius logarithms in the jet mass spectrum beyond leading logarithmic order. We discuss the factorization formulae for the peak and tail region of the jet mass spectrum and for small and large $R$, and the relations between the different regimes and how to combine them. Regions of experimental interest are classified which do not involve large nonglobal logarithms. We also present univer...

  3. Randomness in the dark sector: Emergent mass spectra and Dynamical Dark Matter ensembles

    Science.gov (United States)

    Dienes, Keith R.; Fennick, Jacob; Kumar, Jason; Thomas, Brooks

    2016-04-01

    In general, nonminimal models of the dark sector such as Dynamical Dark Matter posit the existence of an ensemble of individual dark components with differing masses, cosmological abundances, and couplings to the Standard Model. Perhaps the most critical among these features is the spectrum of masses, as this goes a long way towards determining the cosmological abundances and lifetimes of the corresponding states. Many different underlying theoretical structures can be imagined for the dark sector, each giving rise to its own mass spectrum and corresponding density of states. In this paper, by contrast, we investigate the spectrum of masses that emerges statistically from underlying processes which are essentially random. We find a density of states n (m ) which decreases as a function of mass and actually has an upper limit mmax beyond which n (m )=0 . We also demonstrate that this "emergent" density of states is particularly auspicious from the perspective of the Dynamical Dark Matter framework, leading to cosmological abundances and decay widths that are suitably balanced against each other across the dark-matter ensemble. Thus randomness in the dark sector coexists quite naturally with Dynamical Dark Matter, and we examine the prospects for observing the signals of such scenarios in dark-matter indirect-detection experiments.

  4. Randomness in the Dark Sector: Emergent Mass Spectra and Dynamical Dark Matter Ensembles

    CERN Document Server

    Dienes, Keith R; Kumar, Jason; Thomas, Brooks

    2016-01-01

    In general, non-minimal models of the dark sector such as Dynamical Dark Matter posit the existence of an ensemble of individual dark components with differing masses, cosmological abundances, and couplings to the Standard Model. Perhaps the most critical among these features is the spectrum of masses, as this goes a long way towards determining the cosmological abundances and lifetimes of the corresponding states. Many different underlying theoretical structures can be imagined for the dark sector, each giving rise to its own mass spectrum and corresponding density of states. In this paper, by contrast, we investigate the spectrum of masses that emerges statistically from underlying processes which are essentially random. We find a density of states $n(m)$ which decreases as a function of mass and actually has an upper limit $m_{\\rm max}$ beyond which $n(m)=0$. We also demonstrate that this "emergent" density of states is particularly auspicious from the perspective of the Dynamical Dark Matter framework, le...

  5. Theoretical power spectra of mixed modes in low mass red giant stars

    CERN Document Server

    Grosjean, M; Belkacem, K; Montalban, J; Samadi, R; Mosser, B

    2014-01-01

    CoRoT and Kepler observations of red giant stars revealed very rich spectra of non-radial solar-like oscillations. Of particular interest was the detection of mixed modes that exhibit significant amplitude, both in the core and at the surface of the stars. It opens the possibility of probing the internal structure from their inner-most layers up to their surface along their evolution on the red giant branch as well as on the red-clump. Our objective is primarily to provide physical insight into the physical mechanism responsible for mixed-modes amplitudes and lifetimes. Subsequently, we aim at understanding the evolution and structure of red giants spectra along with their evolution. The study of energetic aspects of these oscillations is also of great importance to predict the mode parameters in the power spectrum. Non-adiabatic computations, including a time-dependent treatment of convection, are performed and provide the lifetimes of radial and non-radial mixed modes. We then combine these mode lifetimes a...

  6. Systematics of yrast spectra in neutron-rich nuclei in mass region A=100

    International Nuclear Information System (INIS)

    In this paper the current status of the experimental work in the mass region A=100 is summarized. From the systematics of the observed data an overview of some of the challenging problems posed by neutron-rich nuclei in this mass region is presented. The results of our microscopic study carried out in the variation after projection framework, employing a quadrupole -quadrupole plus pairing model of interaction, for the neutron-rich isotopic mass chains of 88-100Sr, 90-104Zr, 92-106Mo, 94-112Ru, 100-114Pd and 98-110Cd are discussed. Some of the problems observed in this region are explained from these results. (author). 60 refs., 4 figs., 13 tabs

  7. Two-Baryon Correlation Functions in 2-flavour QCD

    CERN Document Server

    Francis, Anthony; Rae, Thomas D; Wittig, Hartmut

    2013-01-01

    We present first results for two-baryon correlation functions, computed using $N_f=2$ flavours of O($a$) improved Wilson quarks, with the aim of explaining potential dibaryon bound states, specifically the H-dibaryon. In particular, we use a GEVP to isolate the groundstate using two-baryon (hyperon-hyperon) correlation functions $\\big(\\langle C_{XY}(t)C_{XY}(0) \\rangle$, where $XY=\\Lambda\\Lambda, \\Sigma\\Sigma, N\\Xi, \\cdots\\big)$, each of which has an overlap with the H-dibaryon. We employ a `blocking' algorithm to handle the large number of contractions, which may easily be extended to N-baryon correlation functions. We also comment on its application to the analysis of single baryon masses ($n$, $\\Lambda$, $\\Xi$, $\\cdots$). This study is performed on an isotropic lattice with $m_\\pi = 460$ MeV, $m_\\pi L = 4.7$ and $a = 0.063$ fm.

  8. Non-baryonic dark matter: observational evidence and detection methods

    International Nuclear Information System (INIS)

    The evidence for the existence of dark matter in the universe is reviewed. A general picture emerges, where both baryonic and non-baryonic dark matter is needed to explain current observations. In particular, a wealth of observational information points to the existence of a non-baryonic component, contributing between around 20 and 40% of the critical mass density needed to make the universe geometrically flat on large scales. In addition, an even larger contribution from vacuum energy (or cosmological constant) is indicated by recent observations. To the theoretically favoured particle candidates for non-baryonic dark matter belong axions, supersymmetric particles, and of less importance, massive neutrinos. The theoretical foundation and experimental situation for each of these is reviewed. Direct and indirect methods for detection of supersymmetric dark matter are described in some detail. Present experiments are just reaching the required sensitivity to discover or rule out some of these candidates, and major improvements are planned over the coming years. (author)

  9. Observation of Electronic Shells and Characteristic Products from Mass Abundance Spectra of Al Cluster and Al-C Cluster Anions

    Institute of Scientific and Technical Information of China (English)

    LIU Bing-Chen; ZHAI Hua-Jin; ZHOU Ru-Fang; NI Guo-Quan; XU Zhi-Zhan

    2000-01-01

    Using a laser vaporization/pulsed molecular beam cluster source, Al cluster anions and Al-C mixed cluster anions are produced and recorded by a time of flight mass spectrometer. Mass abundance spectra of the Al cluster anions in the size range from Al2 to Al42 show that Al-13, Al23, Al35, and slightly, Al37 are local maxima, as predicted by the electronic jellium model. Mixed clusters Aln C- and Aln C2 are also shown, among which the most abundant species are Al3 C2 , Al6 C2 , Al7 C- and Al7 C2 in the small size range. The formation mechanism of these products is discussed.

  10. Mass ordering of spectra from fragmentation of saturated gluon states in high multiplicity proton-proton collisions

    CERN Document Server

    Schenke, Bjoern; Tribedy, Prithwish; Venugopalan, Raju

    2016-01-01

    The mass ordering of mean transverse momentum $\\left$ and of the Fourier harmonic coefficient $v_2 (p_T)$ of azimuthally anisotropic particle distributions in high energy hadron collisions is often interpreted as evidence for the hydrodynamic flow of the matter produced. We investigate an alternative initial state interpretation of this pattern in high multiplicity proton-proton collisions at the LHC. The QCD Yang-Mills equations describing the dynamics of saturated gluons are solved numerically with initial conditions obtained from the Color Glass Condensate based IP-Glasma model. The gluons are subsequently fragmented into various hadron species employing the well established Lund string fragmentation algorithm of the PYTHIA event generator. We find that this ab initio initial state approach reproduces characteristic features of bulk spectra, in particular the particle mass dependence of $\\left$ and $v_2 (p_T)$.

  11. The ρ meson in hot hadron matter and low mass dilepton spectra

    International Nuclear Information System (INIS)

    The structure of the one loop self-energy graphs of the ρ meson is analyzed in the real time formulation of thermal field theory. The modified spectral function of the ρ meson in hot hadronic matter leads to a large enhancement of lepton pair production below the bare peak of the ρ. It has been shown that the effective temperature extracted from the inverse slope of the transverse mass distributions for various invariant mass (M) windows of the pair can be used as an efficient tool to characterize different phases of the evolving matter.

  12. The {rho} meson in hot hadron matter and low mass dilepton spectra

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Sabyasachi; Sarkar, Sourav; Alam, Jan-e [Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata - 700064 (India)

    2011-07-15

    The structure of the one loop self-energy graphs of the {rho} meson is analyzed in the real time formulation of thermal field theory. The modified spectral function of the {rho} meson in hot hadronic matter leads to a large enhancement of lepton pair production below the bare peak of the {rho}. It has been shown that the effective temperature extracted from the inverse slope of the transverse mass distributions for various invariant mass (M) windows of the pair can be used as an efficient tool to characterize different phases of the evolving matter.

  13. Bounds on the cosmological abundance of primordial black holes from diffuse sky brightness single mass spectra

    CERN Document Server

    Custodio, P S

    2002-01-01

    We constrain the mass abundance of unclustered primordial black holes (PBHs), formed with a simple mass distribution and subject to the Hawking evaporation and particle absorption from the environment. Since the radiative flux is proportional to the numerical density, an upper bound is obtained by comparing the calculated and observed diffuse background values, (similarly to the Olbers paradox in which point sources are considered) for finite bandwidths. For a significative range of formation redshifts the bounds are better than several values obtained by other arguments $\\Omega_{pbh} \\leq 10^{-10}$; and they apply to PBHs which are evaporating today.

  14. Mass Spectra of Heavy-Light Mesons in Heavy Hadron Chiral Perturbation Theory

    CERN Document Server

    Alhakami, Mohammad H

    2016-01-01

    We study the masses of the low-lying charm and bottom mesons within the framework of heavy- hadron chiral perturbation theory. We work to third order in the chiral expansion, where meson loops contribute. In contrast to previous approaches, we use physical meson masses in evaluating these loops. This ensures that their imaginary parts are consistent with the observed widths of the D-mesons. The lowest odd- and even-parity, strange and nonstrange charm mesons provide enough constraints to determine only certain linear combinations of the low-energy constants (LECs) in the effective Lagrangian. We comment on how lattice QCD could provide further information to disentangle these constants. Then we use the results from the charm sector to predict the spectrum of odd- and even-parity of the bottom mesons. The predicted masses from our theory are in good agreement with experimentally measured masses for the case of the odd-parity sector. For the even-parity sector, the B-meson states have not yet been observed; thu...

  15. Baryons, Neutrinos, Feedback and Weak Gravitational Lensing

    CERN Document Server

    Harnois-Déraps, Joachim; Viola, Massimo; Heymans, Catherine

    2014-01-01

    (Abridged) The effect of baryonic feedback on the dark matter mass distribution is generally considered to be a nuisance to weak gravitational lensing. Measurements of cosmological parameters are affected as feedback alters the cosmic shear signal on angular scales smaller than a few arcminutes. Recent progress on the numerical modelling of baryon physics has shown that this effect could be so large that, rather than being a nuisance, the effect can be constrained with current weak lensing surveys, hence providing an alternative astrophysical insight on one of the most challenging questions of galaxy formation. In order to perform our analysis, we construct an analytic fitting formula that describes the effect of the baryons on the mass power spectrum. This fitting formula is based on three scenarios of the OWL hydrodynamical simulations. It is specifically calibrated for $z<1.5$, where it models the simulations to an accuracy that is better than $2\\%$ for scales $k<10 h\\mbox{Mpc}^{-1}$ and better than ...

  16. Theoretical perspective for baryon number violation

    International Nuclear Information System (INIS)

    In this talk I describe the theoretical predictions for proton decay and other baryon number violating processes, emphasizing that there are many models and theories involving baryon number violation and that it is an experimental problem to distinguish between them. I first review the the theoretical predictions for the unification mass M/sub X/ and for the weak angle sin2theta/sub W/. It will be seen that the class of models involving an Su3 x SU2 x U1 invariant desert between M/sub W/ and M/sub X/ are strongly favored. I then turn to baryon number violation. The proton lifetime and branching ratio predictions for the SU5 and other 3-2-1 desert models are reviewed, with emphasis on distinguishing between models and on the implications of the small value of the QCD parameter lambda/sub anti MS/ that seems to be favored by the data. I then discuss the consequences of low energy supersymmetry for proton decay, nuclear effects, and models with low mass scales. Finally, I mention possible implications of the anomalously large flux of cosmic ray antiprotons that has recently been reported

  17. The Molecular Baryon Cycle of M82

    CERN Document Server

    Chisholm, John

    2016-01-01

    Baryons cycle into galaxies from the inter-galactic medium, are converted into stars, and a fraction of the baryons are ejected out of galaxies by stellar feedback. Here we present new high resolution (3.9"; 68 pc) CO(2-1) and CO(3-2) images that probe these three stages of the baryon cycle in the nearby starburst M 82. We combine these new observations with previous CO(1-0) and [Fe II] images to study the physical conditions within the molecular gas. Using a Bayesian analysis and the radiative transfer code RADEX, we model molecular Hydrogen temperatures and densities, as well as CO column densities. Besides the disc, we concentrate on two regions within the galaxy: an expanding super-bubble and the base of a molecular streamer. Shock diagnostics, kinematics, and optical extinction suggest that the streamer is an inflowing filament, with a molecular gas mass inflow rate of 3.5 M$_\\odot$ yr$^{-1}$. We measure the molecular gas mass outflow rate of the expanding super-bubble to be 17 M$_\\odot$ yr$^{-1}$, 5 tim...

  18. The pp -> K^+Sigma^+n cross section from missing mass spectra

    OpenAIRE

    Sibirtsev, A.; Haidenbauer, J.; Hammer, H. -W.; Meissner, U. G.

    2007-01-01

    We utilize existing inclusive data on K^+ meson momentum spectra of the reaction pp -> K^+X at T_p = 2.3 - 2.85 GeV to deduce total cross sections for pp -> K^+\\Sigma^+n. The method used to extract those cross sections is explained and discussed in detail. Our result for T_p = 2.85 GeV is consistent with the data point from a direct measurement at the same beam energy. The cross section obtained for T_p = 2.3 GeV is with 13.7\\pm2.3 \\mu b considerably smaller than the value found in a recent e...

  19. Searches of exotic Higgs bosons in general mass spectra of the Georgi-Machacek model at the LHC

    CERN Document Server

    Chiang, Cheng-Wei; Yamada, Toshifumi

    2015-01-01

    We derive the most general sets of viable mass spectra of the exotic Higgs bosons in the Georgi-Machacek model that are consistent with the theoretical constraints of vacuum stability and perturbative unitarity and the experimental constraints of electroweak precision observables, $Zb \\bar b$ coupling and Higgs boson signal strengths. Branching ratios of various cascade decay channels of the doubly-charged Higgs boson in the ${\\bf 5}$ representation, the singly-charged Higgs boson in ${\\bf 3}$, and the singlet Higgs boson are further computed. As one of the most promising channels for discovering the model, we study the prospects for detecting the doubly-charged Higgs boson that is produced via the vector boson fusion process and decays into final states containing a pair of same-sign leptons at the 14-TeV LHC and a 100-TeV future $pp$ collider. For this purpose, we evaluate acceptance times efficiency for signals of the doubly-charged Higgs boson with general viable mass spectra and compare it with the stand...

  20. Semileptonic Decays of Heavy Lambda Baryons in a Quark Model

    Energy Technology Data Exchange (ETDEWEB)

    Winston Roberts; Muslema Pervin; Simon Capstick

    2005-03-01

    The semileptonic decays of {Lambda}{sub c} and {Lambda}{sub b} are treated in the framework of a constituent quark model. Both nonrelativistic and semirelativistic Hamiltonians are used to obtain the baryon wave functions from a fit to the spectra, and the wave functions are expanded in both the harmonic oscillator and Sturmian bases. The latter basis leads to form factors in which the kinematic dependence on q{sup 2} is in the form of multipoles, and the resulting form factors fall faster as a function of q{sup 2} in the available kinematic ranges. As a result, decay rates obtained in the two models using the Sturmian basis are significantly smaller than those obtained using the harmonic oscillator basis. In the case of the {Lambda}{sub c}, decay rates calculated using the Sturmian basis are closer to the experimentally reported rates. However, we find a semileptonic branching fraction for the {Lambda}{sub c} to decay to excited {Lambda}* states of 11% to 19%, in contradiction with what is assumed in available experimental analyses. Our prediction for the {Lambda}{sub b} semileptonic decays is that decays to the ground state {Lambda}{sub c} provide a little less than 70% of the total semileptonic decay rate. For the decays {Lambda}{sub b} {yields} {Lambda}{sub c}, the analytic form factors we obtain satisfy the relations expected from heavy-quark effective theory at the non-recoil point, at leading and next-to-leading orders in the heavy-quark expansion. In addition, some features of the heavy-quark limit are shown to naturally persist as the mass of the heavy quark in the daughter baryon is decreased.

  1. Efficient construction of mock catalogs for baryon acoustic oscillation surveys

    Science.gov (United States)

    Sunayama, Tomomi; Padmanabhan, Nikhil; Heitmann, Katrin; Habib, Salman; Rangel, Esteban

    2016-05-01

    Precision measurements of the large scale structure of the Universe require large numbers of high fidelity mock catalogs to accurately assess, and account for, the presence of systematic effects. We introduce and test a scheme for generating mock catalogs rapidly using suitably derated N-body simulations. Our aim is to reproduce the large scale structure and the gross properties of dark matter halos with high accuracy, while sacrificing the details of the halo's internal structure. By adjusting global and local time-steps in an N-body code, we demonstrate that we recover halo masses to better than 0.5% and the power spectrum to better than 1% both in real and redshift space for k=1hMpc‑1, while requiring a factor of 4 less CPU time. We also calibrate the redshift spacing of outputs required to generate simulated light cones. We find that outputs separated by Δ z=0.05 allow us to interpolate particle positions and velocities to reproduce the real and redshift space power spectra to better than 1% (out to k=1hMpc‑1). We apply these ideas to generate a suite of simulations spanning a range of cosmologies, motivated by the Baryon Oscillation Spectroscopic Survey (BOSS) but broadly applicable to future large scale structure surveys including eBOSS and DESI. As an initial demonstration of the utility of such simulations, we calibrate the shift in the baryonic acoustic oscillation peak position as a function of galaxy bias with higher precision than has been possible so far. This paper also serves to document the simulations, which we make publicly available.

  2. Baryons in Holographic QCD

    CERN Document Server

    Nawa, K; Suganuma, H; Kojo, Toru; Nawa, Kanabu; Suganuma, Hideo

    2006-01-01

    We study the baryon in holographic QCD with $D4/D8/\\bar{D8}$ multi-$D$ brane system. In holographic QCD, the baryon appears as a topologically non-trivial chiral soliton in a four-dimensional effective theory of mesons. We call this topological soliton as Brane-induced Skyrmion. Some review of $D4/D8/\\bar{D8}$ holographic QCD is presented from the viewpoints of recent hadron physics and phenomenologies. Four-dimensional effective theory with pions and $\\rho$ mesons is uniquely derived from the non-abelian Dirac-Born-Infeld (DBI) action of $D8$ brane with $D4$ supergravity background, without small amplitude expansion of meson fields to discuss chiral solitons. For the hedgehog configuration of pion and $\\rho$-meson fields, we derive the energy functional and the Euler-Lagrange equation of Brane-induced Skyrmion from the meson effective action induced by holographic QCD. Performing the numerical calculation, we obtain the pion profile $F(r)$ and the $\\rho$-meson profile $G(r)$ of the Brane-induced Skyrmion, an...

  3. Fitting of Hadron Mass Spectra and Contributions to Perturbation Theory of Conformal Quantum Field Theory

    Science.gov (United States)

    Luna Acosta, German Aurelio

    The masses of observed hadrons are fitted according to the kinematic predictions of Conformal Relativity. The hypothesis gives a remarkably good fit. The isospin SU(2) gauge invariant Lagrangian L(,(pi)NN)(x,(lamda)) is used in the calculation of d(sigma)/d(OMEGA) to 2nd-order Feynman graphs for simplified models of (pi)N(--->)(pi)N. The resulting infinite mass sums over the nucleon (Conformal) families are done via the Generalized-Sommerfeld-Watson Transform Theorem. Even though the models are too simple to be realistic, they indicate that if (DELTA)-internal lines were to be included, 2nd-order Feynman graphs may reproduce the experimental data qualitatively. The energy -dependence of the propagator and couplings in Conformal QFT is different from that of ordinary QFT. Suggestions for further work are made in the areas of ultra-violet divergences and OPEC calculations.

  4. Relativistic kinetics of baryon production in the big bang

    International Nuclear Information System (INIS)

    The baryogenesis process in the early hot universe is investigated by means of relativistic kinetic theory. An exact solution to the kinetic equations for supermassive bosons serves to refine previous results: the optimum baryon-production domain is now complemented by bosons of low mass, thus removing the cosmological lower bound that had limited the mass of superheavy bosons. 14 references

  5. Analysis of Overlapped and Noisy Hydrogen/Deuterium Exchange Mass Spectra

    OpenAIRE

    Guttman, Miklos; Weis, David D.; John R Engen; Lee, Kelly K.

    2013-01-01

    Noisy and overlapped mass spectrometry data hinders the sequence coverage that can be obtained from Hydrogen Deuterium exchange analysis, and places a limit on the complexity of the samples that can be studied by this technique. Advances in instrumentation have addressed these limits, but as the complexity of the biological samples under investigation increases, these problems are reencountered. Here we describe the use of binomial distribution fitting with asymmetric linear squares regressio...

  6. Electromagnetic moments of quasi-stable baryons

    OpenAIRE

    Ledwig, T.; Martin-Camalich, J.; Pascalutsa, V.; Vanderhaeghen, M.

    2011-01-01

    We address electromagnetic properties of quasi-stable baryons in the context of chiral extrapolations of lattice QCD results. For particles near their decay threshold we show that the application of a small external magnetic field changes the particle's energy in a non-analytic way. Conventional electromagnetic moments are only well-defined when the background field B satisfies |eB|/(2M_*|M_*-M-m|) where M_* is the mass of the resonance and M, m the masses of the decay products. An applicatio...

  7. A technique for obtaining matrix-assisted laser desorption/ionization time-of-flight mass spectra of poorly soluble and insoluble aromatic polyamides.

    Science.gov (United States)

    Gies, Anthony P; Nonidez, William K

    2004-04-01

    Wet grinding methods for obtaining matrix-assisted laser desorption/ionization time-of-flight mass spectra of poorly soluble and insoluble low molecular mass oligomers (Nomex and Kevlar are described. Optimum conditions for sample preparation are given along with a detailed analysis of the spectra obtained. Two matrix materials were employed in this analysis, 1,8-dihydroxyanthrone (dithranol) and 3-aminoquinoline with potassium trifluoroacetate used as the cationizing agent. The spectra obtained in this study are sensitive to the matrix, molar mixing ratios of matrix/polymer/cationizing agent, and the sample preparation method. PMID:15053662

  8. Analysis of Overlapped and Noisy Hydrogen/Deuterium Exchange Mass Spectra

    Science.gov (United States)

    Guttman, Miklos; Weis, David D.; Engen, John R.; Lee, Kelly K.

    2013-12-01

    Noisy and overlapped mass spectrometry data hinder the sequence coverage that can be obtained from hydrogen deuterium exchange analysis, and places a limit on the complexity of the samples that can be studied by this technique. Advances in instrumentation have addressed these limits, but as the complexity of the biological samples under investigation increases, these problems are re-encountered. Here we describe the use of binomial distribution fitting with asymmetric linear squares regression for calculating the accurate deuterium content for mass envelopes of low signal or that contain significant overlap. The approach is demonstrated with a test data set of HIV Env gp140 wherein inclusion of the new analysis regime resulted in obtaining exchange data for 42 additional peptides, improving the sequence coverage by 11 %. At the same time, the precision of deuterium uptake measurements was improved for nearly every peptide examined. The improved processing algorithms also provide an efficient method for deconvolution of bimodal mass envelopes and EX1 kinetic signatures. All these functions and visualization tools have been implemented in the new version of the freely available software, HX-Express v2.

  9. Application of exploratory data analysis methods for interpretation and classification of mass spectra

    International Nuclear Information System (INIS)

    Methods for computer-assisted elucidation of spectrum-structure relationships and classification in mass spectrometry have been developed. The core of these procedures are mapping methods from the field of multivariate exploratory data analysis. Mappings enable human visual exploration and interpretation of clustering and class separation. Spectral features derived by using spectral knowledge are applied instead of the peak heights in a mass spectrum. Comparison of the results of 11 different types of supervised and unsupervised mappings revealed three linear mappings to be well fitted for the task: the principal component mapping (PCA), the optimal discriminant plane and a variant of the partial-least-squares mapping (PLS). The common advantages of these mappings are twofold: they are all applied as orthogonal rotations and the mass spectral reasons for clustering of objects and separation of classes can be detected by interpretation of the factor loadings. PCA mappings are sometimes dominated by parts of the spectral data structure, which have no structural meaning. Therefore a PLS-substructure-mapping based on binary structural descriptors as dependent variables has been developed, which is advantageous for the investigation of spectrum-structure-relationships. A statistical substructure analysis is applied to recognize regions in the mapping, which contain similar chemical structures. A FORTRAN program (EDAS-MS) has been implemented on a VAX computer for the application of the methods. (author)

  10. Light Baryon Spectroscopy using the CLAS Spectrometer at Jefferson Laboratory

    CERN Document Server

    Crede, Volker

    2011-01-01

    Baryons are complex systems of confined quarks and gluons and exhibit the characteristic spectra of excited states. The systematics of the baryon excitation spectrum is important to our understanding of the effective degrees of freedom underlying nucleon matter. High-energy electrons and photons are a remarkably clean probe of hadronic matter, providing a microscope for examining the nucleon and the strong nuclear force. Current experimental efforts with the CLAS spectrometer at Jefferson Laboratory utilize highly-polarized frozen-spin targets in combination with polarized photon beams. The status of the recent double-polarization experiments and some preliminary results are discussed in this contribution.

  11. High Statistics Analysis using Anisotropic Clover Lattices: (III) Baryon-Baryon Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Beane, Silas [Univ. of New Hampshire, Durham, NH (United States); Detmold, William [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Lin, Huey-Wen [Univ. of Washington, Seattle, WA (United States); Luu, Thomas C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Orginos, Kostas [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Savage, Martin [Univ. of Washington, Seattle, WA (United States); Torok, Aaron M. [Indiana Univ., Bloomington, IN (United States). Dept. of Physics; Walker-Loud, Andre [College of William and Mary, Williamsburg, VA (United States)

    2010-03-01

    Low-energy baryon-baryon interactions are calculated in a high-statistics lattice QCD study on a single ensemble of anisotropic clover gauge-field configurations at a pion mass of m_pi ~ 390 MeV, a spatial volume of L^3 ~ (2.5 fm)^3, and a spatial lattice spacing of b ~ 0.123 fm. Luscher’s method is used to extract nucleon-nucleon, hyperon-nucleon and hyperon-hyperon scattering phase shifts at one momentum from the one- and two-baryon ground-state energies in the lattice volume. The N-Sigma interactions are found to be highly spin-dependent, and the interaction in the ^3 S _1 channel is found to be strong. In contrast, the N-Lambda interactions are found to be spin-independent, within the uncertainties of the calculation, consistent with the absence of one-pion-exchange. The only channel for which a negative energy-shift is found is Lambda-Lambda, indicating that the Lambda-Lambda interaction is attractive, as anticipated from model-dependent discussions regarding the H-dibaryon. The NN scattering lengths are found to be small, clearly indicating the absence of any fine-tuning in the NN-sector at this pion mass. This is consistent with our previous Lattice QCD calculation of the NN interactions. The behavior of the signal-to-noise ratio in the baryon-baryon correlation functions, and in the ratio of correlation functions that yields the ground-state energy splitting

  12. The $\\rho$ meson in hot hadron matter and low mass dilepton spectra

    CERN Document Server

    Ghosh, Sabyasachi; Alam, Jan-e

    2011-01-01

    The structure of the one loop self-energy graphs of the $\\rho$ meson is analyzed in the real time formulation of thermal field theory. The modified spectral function of the $\\rho$ meson in hot hadronic matter leads to a large enhancement of lepton pair production below the bare peak of the $\\rho$. It has been shown that the effective temperature extracted from the inverse slope of the transverse momentum distributions for various invariant mass ($M$) windows of the pair can be used as an efficient tool to characterize different phases of the evolving matter.

  13. Optical emission and mass spectra observations during hydrogen combustion in atmospheric pressure microwave plasma

    International Nuclear Information System (INIS)

    We experimentally investigated hydrogen combustion by atmospheric pressure plasma generated by a 2.45 GHz microwave discharge. Small amounts of hydrogen and oxygen were mixed in the operational argon gas during discharge. To clarify the details of combustion, optical emission was measured. The constituents of combustion-processed gases were observed by a quadruple mass spectrometer. The degree of hydrogen oxidation, the so-called conversion rate, increased with input microwave power. The maximum hydrogen conversion rate was greater than 80% under these experimental conditions. During discharge, an optical emission peak due to OH radicals was observed. (author)

  14. Nucleon, Delta and Omega excited state spectra at three pion mass values

    International Nuclear Information System (INIS)

    The energies of the excited states of the Nucleon, Delta and Omega are computed in lattice QCD, using two light quarks and one strange quark on anisotropic lattices. The calculations are performed at three values of the pion mass: 392(4), 438(3) and 521(3) MeV. We employ the variational method with a basis of about ten interpolating operators enabling six energies to be distinguished clearly in each irreducible representation of the octahedral group. We compare our calculations of nucleon excited states with the low-lying experimental spectrum. There is reasonable agreement for the pattern of states.

  15. Study of baryon number and lepton flavour violation in the new minimal supersymmetric SO(10)GUT

    CERN Document Server

    Kaur, Charanjit

    2015-01-01

    We study the so-called new minimal supersymmetric SO(10) GUT(NMSGUT) where explicit spontaneous symmetry breaking allows determination of superheavy spectrum and thus threshold corrections to the effective MSSM couplings. This provides a generic mechanism to resolve the long standing super fast proton decay in Susy GUTs. We estimate lepton flavor violation associated with realistic charged fermion and (Type I seesaw) neutrino fit and show compatibility with baryon number and lepton flavour violation limits. We improve NMSGUT fits by including important loop corrections to sparticle spectra. Our fits use 5 GUT compatible soft supersymmetry breaking parameters of the Supergravity with Non-Universal Higgs Masses(SUGRY-NUHM) type. We calculate the full two loop NMSGUT gauge-Yukawa beta functions to study feasibility of the NUHM parameters via strong renormalization of SO(10) Higgs soft masses. Focus on MSSM Higgs allows formulation of a "Yukawonification" strategy for gauged flavour unification.

  16. CycloBranch: De Novo Sequencing of Nonribosomal Peptides from Accurate Product Ion Mass Spectra

    Science.gov (United States)

    Novák, Jiří; Lemr, Karel; Schug, Kevin A.; Havlíček, Vladimír

    2015-07-01

    Nonribosomal peptides have a wide range of biological and medical applications. Their identification by tandem mass spectrometry remains a challenging task. A new open-source de novo peptide identification engine CycloBranch was developed and successfully applied in identification or detailed characterization of 11 linear, cyclic, branched, and branch-cyclic peptides. CycloBranch is based on annotated building block databases the size of which is defined by the user according to ribosomal or nonribosomal peptide origin. The current number of involved nonisobaric and isobaric building blocks is 287 and 521, respectively. Contrary to all other peptide sequencing tools utilizing either peptide libraries or peptide fragment libraries, CycloBranch represents a true de novo sequencing engine developed for accurate mass spectrometric data. It is a stand-alone and cross-platform application with a graphical and user-friendly interface; it supports mzML, mzXML, mgf, txt, and baf file formats and can be run in parallel on multiple threads. It can be downloaded for free from http://ms.biomed.cas.cz/cyclobranch/, where the User's manual and video tutorials can be found.

  17. Energy spectra of massive two-body decay products and mass measurement

    CERN Document Server

    Agashe, Kaustubh; Hong, Sungwoo; Kim, Doojin

    2016-01-01

    We have recently established a new method for measuring the mass of unstable particles produced at hadron colliders based on the analysis of the energy distribution of a massless product from their two-body decays. The central ingredient of our proposal is the remarkable result that, for an unpolarized decaying particle, the location of the peak in the energy distribution of the observed decay product is identical to the (fixed) value of the energy that this particle would have in the rest-frame of the decaying particle, which, in turn, is a simple function of the involved masses. In addition, we utilized the property that this energy distribution is symmetric around the location of peak when energy is plotted on a logarithmic scale. The general strategy was demonstrated in several specific cases, including both beyond the SM particles, as well as for the top quark. In the present work, we generalize this method to the case of a massive decay product from a two-body decay; this procedure is far from trivial b...

  18. Stellar mass-to-light ratios from galaxy spectra: how accurate can they be?

    CERN Document Server

    Gallazzi, Anna

    2009-01-01

    Stellar masses play a crucial role in the exploration of galaxy properties and the evolution of the galaxy population. In this paper, we explore the minimum possible uncertainties in stellar mass-to-light (M/L) ratios from the assumed star formation history (SFH) and metallicity distribution, with the goals of providing a minimum set of requirements for observational studies. We use a large Monte Carlo library of SFHs to study as a function of galaxy spectral type and signal-to-noise ratio (S/N) the statistical uncertainties of M/L values using either absorption-line data or broad band colors. The accuracy of M/L estimates can be significantly improved by using metal-sensitive indices in combination with age-sensitive indices, in particular for galaxies with intermediate-age or young stellar populations. While M/L accuracy clearly depends on the spectral S/N ratio, there is no significant gain in improving the S/N much above 50/pix and limiting uncertainties of 0.03 dex are reached. Assuming that dust is accu...

  19. Dynamic Bayesian Network for Accurate Detection of Peptides from Tandem Mass Spectra.

    Science.gov (United States)

    Halloran, John T; Bilmes, Jeff A; Noble, William S

    2016-08-01

    A central problem in mass spectrometry analysis involves identifying, for each observed tandem mass spectrum, the corresponding generating peptide. We present a dynamic Bayesian network (DBN) toolkit that addresses this problem by using a machine learning approach. At the heart of this toolkit is a DBN for Rapid Identification (DRIP), which can be trained from collections of high-confidence peptide-spectrum matches (PSMs). DRIP's score function considers fragment ion matches using Gaussians rather than fixed fragment-ion tolerances and also finds the optimal alignment between the theoretical and observed spectrum by considering all possible alignments, up to a threshold that is controlled using a beam-pruning algorithm. This function not only yields state-of-the art database search accuracy but also can be used to generate features that significantly boost the performance of the Percolator postprocessor. The DRIP software is built upon a general purpose DBN toolkit (GMTK), thereby allowing a wide variety of options for user-specific inference tasks as well as facilitating easy modifications to the DRIP model in future work. DRIP is implemented in Python and C++ and is available under Apache license at http://melodi-lab.github.io/dripToolkit . PMID:27397138

  20. A database of chromatographic properties and mass spectra of fatty acid methyl esters from omega-3 products.

    Science.gov (United States)

    Wasta, Ziar; Mjøs, Svein A

    2013-07-19

    Fatty acids in products claimed to contain oils with the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were analyzed as fatty acid methyl esters by gas chromatography-mass spectrometry using electron impact ionization. To cover the variation in products on the market, the 20 products that were studied in detail were selected from a larger sample set by statistical methodology. The samples were analyzed on two different stationary phases (polyethylene glycol and cyanopropyl) and the fatty acid methyl esters were identified by methodology that combines the mass spectra and retention indices into a single score value. More that 100 fatty acids had a chromatographic area above 0.1% of the total, in at least one product. Retention indices are reported as equivalent chain lengths, and overlap patterns on the two columns are discussed. Both columns were found suitable for analysis of major and nutritionally important fatty acids, but the large number of minor compounds that may act as interferents will be problematic if low limits of quantification are required in analyses of similar sample types. A database of mass spectral libraries and equivalent chain lengths of the detected compounds has been compiled and is available online. PMID:23773584

  1. Simultaneous factor analysis of organic particle and gas mass spectra: AMS and PTR-MS measurements at an urban site

    Directory of Open Access Journals (Sweden)

    J. G. Slowik

    2009-03-01

    Full Text Available During the winter component of the SPORT (Seasonal Particle Observations in the Region of Toronto field campaign, particulate non-refractory chemical composition and concentration of selected volatile organic compounds (VOCs were measured by an Aerodyne time-of-flight aerosol mass spectrometer (AMS and a proton transfer reaction-mass spectrometer (PTR-MS, respectively. Sampling was performed in downtown Toronto ~15 m from a major road. The mass spectra from the AMS and PTR-MS were combined into a unified dataset, which was analyzed using positive matrix factorization (PMF. The two instruments were given equal weight in the PMF analysis by application of a scaling factor to the uncertainties of each instrument. A residual based metric, Δesc, was used to evaluate the relative weight. The PMF analysis yielded a 5-factor solution that included factors characteristic of regional transport, local traffic emissions, charbroiling, and oxidative processing. The unified dataset provides information on particle and VOC sources and atmospheric processing that cannot be obtained from the datasets of the individual instruments, such as apportionment of oxygenated VOCs to direct emission sources vs. secondary reaction products, improved correlation of oxygenated aerosol factors with photochemical age, and increased detail regarding the composition of oxygenated organic aerosol factors. This analysis represents the first application of PMF to a unified AMS/PTR-MS dataset.

  2. Comparison of two cluster analysis methods using single particle mass spectra

    Science.gov (United States)

    Zhao, Weixiang; Hopke, Philip K.; Prather, Kimberly A.

    Cluster analysis of aerosol time-of-flight mass spectrometry (ATOFMS) data has been an effective tool for the identification of possible sources of ambient aerosols. In this study, the clustering results of two typical methods, adaptive resonance theory-based neural networks-2a (ART-2a) and density-based clustering of application with noise (DBSCAN), on ATOFMS data were investigated by employing a set of benchmark ATOFMS data. The advantages and disadvantages of these two methods are discussed and some feasible remedies proposed for problems encountered in the clustering process. The results of this study will provide promising directions for future work on ambient aerosol cluster analysis, suggesting a more effective and feasible clustering strategy based on the integration of ART-2a and DBSCAN.

  3. An application of artificial intelligence to the interpretation of mass spectra.

    Science.gov (United States)

    Buchanan, B. G.; Duffield, A. M.; Robertson, A. V.

    1971-01-01

    Description of the DENDRAL (Dendritic Algorithm) project, the objectives of which were to base the computer program on an alogorithm that generates an exhaustive, nonredundant list of all the structural isomers of a given chemical composition, and to devise a computer program that would perform an organic structure determination, given a molecular formula and a mass spectrum. This program is called 'Heuristic DENDRAL' and it operates by using the known structure/spectrum correlations to constrain the DENDRAL isomer generator to produce a single isomer for that composition. The collaboration of chemists and computer scientists has produced a tool of some practical utility from the chemical viewpoint, and an interesting program from the viewpoint of artificial intelligence.

  4. Penta-quark baryon from the QCD Sum Rule

    CERN Document Server

    Sugiyama, J; Oka, M; Sugiyama, Jun; Doi, Takumi; Oka, Makoto

    2004-01-01

    Exotic penta-quark baryon with strangeness +1, \\Theta^+, is studied in the QCD sum rule approach. We derive sum rules for the positive and negative parity baryon states with J=1/2 and I=0. It is found that the standard values of the QCD condensates predict a negative parity \\Theta^+ of mass \\simeq 1.5 GeV, while no positive parity state is found. We stress the roles of chiral-odd condensates in determining the parity and mass of \\Theta^+.

  5. Excited Baryon Spectroscopy in the Large $N_c$ Limit

    CERN Document Server

    Goity, J L

    1996-01-01

    The leading in 1/N_c spin-flavor symmetry breaking mass splittings, of order N_c^0, in excited non-strange Baryons are shown to be given, up to two-body operators, by three different effective Hamiltonians: Thomas precession spin-orbit, spin-isospin tensor, and spin-orbit with isospin exchange. Explicit expressions for their matrix elements between low excited Baryons are obtained, and the structure of the mass splittings in large N_c is established to first order of perturbation theory. The problem of extending the large N_c results to the real world with N_c=3 is briefly addressed.

  6. Staggered heavy baryon chiral perturbation theory

    Science.gov (United States)

    Bailey, Jon A.

    2008-03-01

    Although taste violations significantly affect the results of staggered calculations of pseudoscalar and heavy-light mesonic quantities, those entering staggered calculations of baryonic quantities have not been quantified. Here I develop staggered chiral perturbation theory in the light-quark baryon sector by mapping the Symanzik action into heavy baryon chiral perturbation theory. For 2+1 dynamical quark flavors, the masses of flavor-symmetric nucleons are calculated to third order in partially quenched and fully dynamical staggered chiral perturbation theory. To this order the expansion includes the leading chiral logarithms, which come from loops with virtual decuplet-like states, as well as terms of O(mπ3), which come from loops with virtual octet-like states. Taste violations enter through the meson propagators in loops and tree-level terms of O(a2). The pattern of taste symmetry breaking and the resulting degeneracies and mixings are discussed in detail. The resulting chiral forms are appropriate to lattice results obtained with operators already in use and could be used to study the restoration of taste symmetry in the continuum limit. I assume that the fourth root of the fermion determinant can be incorporated in staggered chiral perturbation theory using the replica method.

  7. Baryon Production in the String Fragmentation Picture

    OpenAIRE

    Eden, Patrik; Gustafson, Gosta

    1996-01-01

    An improved version of the ``pop-corn'' model for baryon production in quark and gluon jets is presented. With a reduced number of parameters the model reproduces well both production rates for different baryon species and baryon momentum distributions. Predictions are presented for a set of baryon-antibaryon correlations.

  8. Analysis of the Triply Heavy Baryon States with QCD Sum Rules

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-Gang

    2012-01-01

    In this article, we study the (1/2)± and (3/2)± triply heavy baryon states in a systematic way by subtracting the contributions from the corresponding (1/2) and (3/2) triply heavy baryon states with the QCD sum rules, and make reasonable predictions for their masses.

  9. A Study of the Mass Spectra of Fission Fragments after Prompt Neutron Emission

    International Nuclear Information System (INIS)

    The distribution of the masses of fission fragments, following neutron emission, was obtained by simultaneously measuring the velocity and energy of each particle. The special feature of this method is that it is essentially independent of the initial energy of the fragments, so that we were able to use relatively thick targets of fissionable material (0.1 mg/cm2). The energy measurement is made by a gold-silicon surface barrier detector: the velocity measurement was made on a flight path of 130 cm, with a total resolving power of 1.5 ns; The ''starting'' detector consisted of a windowless photomultiplier that detected directly the secondary electrons emitted by a thin metallic sheet during the passage of the fission fragments. The ''stop'' signal is picked up directly, by means of a transformer, on the semi-conductor detector. The results given in the paper relate to the thermal fission of U235, and are compared with the results obtained by the radiochemical method. (author)

  10. Searching for Earth-mass planets around $\\alpha$ Centauri: precise radial velocities from contaminated spectra

    CERN Document Server

    Bergmann, Christoph; Hearnshaw, John B; Wittenmyer, Robert A; Wright, Duncan J

    2014-01-01

    This work is part of an ongoing project which aims to detect terrestrial planets in our neighbouring star system $\\alpha$ Centauri using the Doppler method. Owing to the small angular separation between the two components of the $\\alpha$ Cen AB binary system, the observations will to some extent be contaminated with light coming from the other star. We are accurately determining the amount of contamination for every observation by measuring the relative strengths of the H-$\\alpha$ and NaD lines. Furthermore, we have developed a modified version of a well established Doppler code that is modelling the observations using two stellar templates simultaneously. With this method we can significantly reduce the scatter of the radial velocity measurements due to spectral cross-contamination and hence increase our chances of detecting the tiny signature caused by potential Earth-mass planets. After correcting for the contamination we achieve radial velocity precision of $\\sim 2.5\\,\\mathrm{m\\,s^{-1}}$ for a given night...

  11. Simplification of electrospray mass spectra of Polysorbate 80 via cation transfer to carborane anions.

    Science.gov (United States)

    Betancourt, Stella K; Pilo, Alice L; Bu, Jiexun; McLuckey, Scott A

    2016-06-01

    Mass spectrometric analysis of polymer mixtures via electrospray ionization can be complicated due the presence of multiple ion types, multiple charge states and multiple oligomeric distributions that complicate the detection and identification of mixture components. Polysorbate 80 (commercially known as Tween(®) 80) provides an example of this type, where the presence of polyoxyethylene sorbitan monooleate (PSO) byproducts gives rise to overlapping polymer distributions. It is desirable to simplify the spectrum in order to identify each component of what is inherently a complex mixture of fatty esters bound to different head groups. In this work, we show that gas-phase ion/ion reactions with carborane anions allow for the charge reduction of Tween(®) 80 peaks by selectively removing metal adducts bound to the synthetic polymer. The resulting singly charged spectrum reduces overlapping distributions and thus simplifies the identification of the components found in a Tween(®) 80 sample. The overall approach described here would likely lead to similar benefits in the analysis of other polymers that tend to ionize via metal ion adduction. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27270869

  12. A database application for pre-processing, storage and comparison of mass spectra derived from patients and controls

    Directory of Open Access Journals (Sweden)

    Sillevis Smitt Peter A

    2006-09-01

    Full Text Available Abstract Background Statistical comparison of peptide profiles in biomarker discovery requires fast, user-friendly software for high throughput data analysis. Important features are flexibility in changing input variables and statistical analysis of peptides that are differentially expressed between patient and control groups. In addition, integration the mass spectrometry data with the results of other experiments, such as microarray analysis, and information from other databases requires a central storage of the profile matrix, where protein id's can be added to peptide masses of interest. Results A new database application is presented, to detect and identify significantly differentially expressed peptides in peptide profiles obtained from body fluids of patient and control groups. The presented modular software is capable of central storage of mass spectra and results in fast analysis. The software architecture consists of 4 pillars, 1 a Graphical User Interface written in Java, 2 a MySQL database, which contains all metadata, such as experiment numbers and sample codes, 3 a FTP (File Transport Protocol server to store all raw mass spectrometry files and processed data, and 4 the software package R, which is used for modular statistical calculations, such as the Wilcoxon-Mann-Whitney rank sum test. Statistic analysis by the Wilcoxon-Mann-Whitney test in R demonstrates that peptide-profiles of two patient groups 1 breast cancer patients with leptomeningeal metastases and 2 prostate cancer patients in end stage disease can be distinguished from those of control groups. Conclusion The database application is capable to distinguish patient Matrix Assisted Laser Desorption Ionization (MALDI-TOF peptide profiles from control groups using large size datasets. The modular architecture of the application makes it possible to adapt the application to handle also large sized data from MS/MS- and Fourier Transform Ion Cyclotron Resonance (FT-ICR mass

  13. Source apportionment of submicron organic aerosols at an urban site by linear unmixing of aerosol mass spectra

    Directory of Open Access Journals (Sweden)

    V. A. Lanz

    2006-11-01

    Full Text Available Submicron ambient aerosol was characterized in summer 2005 at an urban background site in Zurich, Switzerland, during a three-week measurement campaign. Highly time-resolved samples of non-refractory aerosol components were analyzed with an Aerodyne aerosol mass spectrometer (AMS. Positive matrix factorization (PMF was used for the first time for AMS data to identify the main components of the total organic aerosol and their sources. The PMF retrieved factors were compared to measured reference mass spectra and were correlated with tracer species of the aerosol and gas phase measurements from collocated instruments. Six factors were found to explain virtually all variance in the data and could be assigned either to sources or to aerosol components such as oxygenated organic aerosol (OOA. Our analysis suggests that at the measurement site only a small (<10% fraction of organic PM1 originates from freshly emitted fossil fuel combustion. Other primary sources identified to be of similar or even higher importance are charbroiling (10–15% and wood burning (~10%, along with a minor source interpreted to be influenced by food cooking (6%. The fraction of all identified primary sources is considered as primary organic aerosol (POA. This interpretation is supported by calculated ratios of the modelled POA and measured primary pollutants such as elemental carbon (EC, NOx, and CO, which are in good agreement to literature values. A high fraction (60–69% of the measured organic aerosol mass is OOA which is interpreted mostly as secondary organic aerosol (SOA. This oxygenated organic aerosol can be separated into a highly aged fraction, OOA I, (40–50% with low volatility and a mass spectrum similar to fulvic acid, and a more volatile and probably less processed fraction, OOA II (on average 20%. This is the first publication of a multiple component analysis technique to AMS organic spectral data and also the first report of the

  14. Excited baryons from Bayesian priors and overlap fermions

    Energy Technology Data Exchange (ETDEWEB)

    F.X. Lee; S.J. Dong; T. Draper; I. Horvath; K.F. Liu; N. Mathur; J.B. Zhang

    2003-05-01

    Using the constrained-fitting method based on Bayesian priors, we extract the masses of the two lowest states of octet and decouplet baryons with both parities. The calculation is done on quenched 163 x 28 lattices of a = 0.2 fm using an improved gauge action and overlap fermions, with the pion mass as low as 180 MeV. The Roper state N(1440)+ is clearly observed for the first time as the 1st-excited state of the nucleon from the standard interpolating field. Together with other baryons, our preliminary results indicate that the level-ordering of the low-lying baryon states on the lattice is largely consistent with experiment. The realization is helped by cross-overs between the excited + and - states in the region of mp 300 to 400 MeV.

  15. Shedding light on baryonic dark matter

    Science.gov (United States)

    Silk, Joseph

    1991-01-01

    Halo dark matter, if it is baryonic, may plausibly consist of compact stellar remnants. Jeans mass clouds containing 10 to the 6th to 10 to the 8th solar masses could have efficiently formed stars in the early universe and could plausibly have generated, for a suitably top-heavy stellar initial mass function, a high abundance of neutron stars as well as a small admixture of long-lived low mass stars. Within the resulting clusters of dark remnants, which eventually are tidally disrupted when halos eventually form, captures of neutron stars by nondegenerate stars resulted in formation of close binaries. These evolve to produce, by the present epoch, an observable X-ray signal associated with dark matter aggregations in galaxy cluster cores.

  16. Baryon mapping of quark systems

    CERN Document Server

    Sambataro, M

    1995-01-01

    We discuss a mapping procedure from a space of colorless three-quark clusters into a space of elementary baryons and illustrate it in the context of a three-color extension of the Lipkin model recently developed. Special attention is addressed to the problem of the formation of unphysical states in the mapped space. A correspondence is established between quark and baryon spaces and the baryon image of a generic quark operator is defined both in its Hermitian and non-Hermitian forms. Its spectrum (identical in the two cases) is found to consist of a physical part containing the same eigenvalues of the quark operator in the cluster space and an unphysical part consisting only of zero eigenvalues. A physical subspace of the baryon space is also defined where the latter eigenvalues are suppressed. The procedure discussed is quite general and applications of it can be thought also in the correspondence between systems of 2n fermions and n bosons.

  17. Baryon Instability in SUSY Models

    OpenAIRE

    Nath, Pran; Arnowitt, R.

    1996-01-01

    Comment: 14 pages, latex, 1 fig, to be published in proceedings of the International Workshop on " Future Prospects of Baryon Instability Search in p-Decay and n-nbar Oscillation Experiments", Oak Ridge, Tennessee, March 28-30,1996

  18. BARYON LOADED RELATIVISTIC BLAST WAVES IN SUPERNOVAE

    International Nuclear Information System (INIS)

    We provide a new analytic blast wave solution which generalizes the Blandford-McKee solution to arbitrary ejecta masses and Lorentz factors. Until recently relativistic supernovae have been discovered only through their association with long-duration gamma-ray bursts (GRBs). The blast waves of such explosions are well described by the Blandford-McKee (in the ultra-relativistic regime) and Sedov-Taylor (in the non-relativistic regime) solutions during their afterglows, as the ejecta mass is negligible in comparison to the swept-up mass. The recent discovery of the relativistic supernova SN 2009bb, without a detected GRB, opens up the possibility of highly baryon loaded, mildly relativistic outflows which remains in nearly free-expansion phase during the radio afterglow. In this work, we consider a massive, relativistic shell, launched by a Central Engine Driven EXplosion (CEDEX), decelerating adiabatically due to its collision with the pre-explosion circumstellar wind profile of the progenitor. We compute the synchrotron emission from relativistic electrons in the shock amplified magnetic field. This models the radio emission from the circumstellar interaction of a CEDEX. We show that this model explains the observed radio evolution of the prototypical SN 2009bb and demonstrate that SN 2009bb had a highly baryon loaded, mildly relativistic outflow. We discuss the effect of baryon loading on the dynamics and observational manifestations of a CEDEX. In particular, our predicted angular size of SN 2009bb is consistent with very long baseline interferometric (VLBI) upper limits on day 85, but is presently resolvable on VLBI angular scales, since the relativistic ejecta is still in the nearly free-expansion phase.

  19. Statistical analysis of fragmentation patterns of electron ionization mass spectra of enolized-trimethylsilylated anabolic androgenic steroids

    Science.gov (United States)

    Fragkaki, A. G.; Angelis, Y. S.; Tsantili-Kakoulidou, A.; Koupparis, M.; Georgakopoulos, C.

    2009-08-01

    Anabolic androgenic steroids (AAS) are included in the List of prohibited substances of the World Anti-Doping Agency (WADA) as substances abused to enhance athletic performance. Gas chromatography coupled to mass spectrometry (GC-MS) plays an important role in doping control analyses identifying AAS as their enolized-trimethylsilyl (TMS)-derivatives using the electron ionization (EI) mode. This paper explores the suitability of complementary GC-MS mass spectra and statistical analysis (principal component analysis, PCA and partial least squares-discriminant analysis, PLS-DA) to differentiate AAS as a function of their structural and conformational features expressed by their fragment ions. The results obtained showed that the application of PCA yielded a classification among the AAS molecules which became more apparent after applying PLS-DA to the dataset. The application of PLS-DA yielded a clear separation among the AAS molecules which were, thus, classified as: 1-ene-3-keto, 3-hydroxyl with saturated A-ring, 1-ene-3-hydroxyl, 4-ene-3-keto, 1,4-diene-3-keto and 3-keto with saturated A-ring anabolic steroids. The study of this paper also presents structurally diagnostic fragment ions and dissociation routes providing evidence for the presence of unknown AAS or chemically modified molecules known as designer steroids.

  20. Mass spectra and fusion cross sections for 20Ne + 24Mg interaction at 55 MeV and 85 MeV

    International Nuclear Information System (INIS)

    Inclusive γ-spectra from the 20Ne + 24Mg interaction have been measured using 55 and 85 MeV 20Ne beams accelerated at the CYCLONE cyclotron of Louvain-la-Neuve. The identification of γ lines allows the determination of mass spectra in the region 12<=A<=43. Experimental results are compared with statistical model calculations. The total reaction and fusion cross sections are extracted. Cross sections for inelastic scattering, few nucleon transfers and deep inelastic scattering are estimated. (author)

  1. Baryon resonances in a chiral confining model, 1

    CERN Document Server

    Umino, Y

    1998-01-01

    In this two part series a chiral confining model of baryons is used to describe low--lying negative parity resonances $N^*$, $\\Delta^*$, $\\Lambda^*$ and $\\Sigma^*$ in the mean field approximation. A physical baryon in this model consists of interacting valence quarks, mesons and a color and chiral singlet hybrid field coexisting inside a dynamically generated confining region. This first paper presents the quark contribution to the masses and wave functions of negative parity baryons calculated with an effective spin--isospin dependent instanton induced interaction. It does not include meson exchanges between quarks. The three--quark wave functions are used to calculate meson--excited baryon vertex functions to lowest order in meson--quark coupling. When the baryons are on mass--shell each of these vertex functions is a product of a coupling constant and a form factor. As examples, quark contributions to $N^*$ hadronic form factors as well as axial coupling constants are extracted from the vertex functions an...

  2. Baryonic Operators for Lattice Simulations

    CERN Document Server

    Edwards, R; Fleming, G; Heller, U M; Morningstar, C J; Richards, D; Sato, I; Wallace, S

    2004-01-01

    The construction of baryonic operators for determining the N* excitation spectrum is discussed. The operators are designed with one eye towards maximizing overlaps with the low-lying states of interest, and the other eye towards minimizing the number of sources needed in computing the required quark propagators. Issues related to spin identification are outlined. Although we focus on tri-quark baryon operators, the construction method is applicable to both mesons and penta-quark operators.

  3. A new method to discriminate secondary organic aerosols from different sources using high-resolution aerosol mass spectra

    Directory of Open Access Journals (Sweden)

    M. F. Heringa

    2012-02-01

    Full Text Available Organic aerosol (OA represents a significant and often major fraction of the non-refractory PM1 (particulate matter with an aerodynamic diameter da < 1 μm mass. Secondary organic aerosol (SOA is an important contributor to the OA and can be formed from biogenic and anthropogenic precursors. Here we present results from the characterization of SOA produced from the emissions of three different anthropogenic sources. SOA from a log wood burner, a Euro 2 diesel car and a two-stroke Euro 2 scooter were characterized with an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS and compared to SOA from α-pinene.

    The emissions were sampled from the chimney/tailpipe by a heated inlet system and filtered before injection into a smog chamber. The gas phase emissions were irradiated by xenon arc lamps to initiate photo-chemistry which led to nucleation and subsequent particle growth by SOA production.

    Duplicate experiments were performed for each SOA type, with the averaged organic mass spectra showing Pearson's r values >0.94 for the correlations between the four different SOA types after five hours of aging. High-resolution mass spectra (HR-MS showed that the dominant peaks in the MS, m/z 43 and 44, are dominated by the oxygenated ions C2H3O+ and CO2+, respectively, similarly to the relatively fresh semi-volatile oxygenated OA (SV-OOA observed in the ambient aerosol. The atomic O:C ratios were found to be in the range of 0.25–0.55 with no major increase during the first five hours of aging. On average, the diesel SOA showed the lowest O:C ratio followed by SOA from wood burning, α-pinene and the scooter emissions. Grouping the fragment ions revealed that the SOA source with the highest O:C ratio had the largest fraction of small ions.

    The HR data of the four sources could be clustered and separated using

  4. A new method to discriminate secondary organic aerosols from different sources using high-resolution aerosol mass spectra

    Directory of Open Access Journals (Sweden)

    M. F. Heringa

    2011-10-01

    Full Text Available Organic aerosol (OA represents a significant and often major fraction of the non-refractory PM1 (particulate matter with an aerodynamic diameter da < 1 μm mass. Secondary organic aerosol (SOA is an important contributor to the OA and can be formed from biogenic and anthropogenic precursors. Here we present results from the characterization of SOA produced from the emissions of three different anthropogenic sources. SOA from a log wood burner, a Euro 2 diesel car and a two-stroke Euro 2 scooter were characterized with an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS and compared to SOA from α-pinene.

    The emissions were sampled from the chimney/tailpipe by a heated inlet system and filtered before injection into a smog chamber. The gas phase emissions were irradiated by xenon arc lamps to initiate photo-chemistry which led to nucleation and subsequent particle growth by SOA production.

    Duplicate experiments were performed for each SOA type, with the averaged organic mass spectra in the m/z range 12–250 showing Pearson's r values >0.94 for the correlations between the different SOA types after 5 h of aging. High-resolution mass spectra (HR-MS showed that the dominant peaks in the MS, m/z 43 and 44, are dominated by the oxygenated ions C2H3O+ and CO2+, respectively, similarly to the relatively fresh semi-volatile oxidized OA (SV-OOA observed in the ambient aerosol. The atomic O : C ratios were found to be in the range of 0.25–0.55 with no major increase during the first 5 h of aging. On average, the diesel SOA showed the lowest O : C ratio followed by SOA from wood burning, α-pinene and the scooter emissions. Grouping the fragment ions based on their carbon number revealed that the SOA source with the highest O : C ratio had the largest fraction of small ions. Fragment ions

  5. Cosmology with X-ray Cluster Baryons

    Energy Technology Data Exchange (ETDEWEB)

    Linder, Eric V.

    2007-04-10

    X-ray cluster measurements interpreted with a universal baryon/gas mass fraction can theoretically serve as a cosmological distance probe. We examine issues of cosmological sensitivity for current (e.g., Chandra X-ray Observatory, XMM-Newton) and next generation (e.g., Con-X, XEUS) observations, along with systematic uncertainties and biases. To give competitive next generation constraints on dark energy, we find that systematics will need to be controlled to better than 1percent and any evolution in f_gas (and other cluster gas properties) must be calibrated so the residual uncertainty is weaker than (1+z)0.03.

  6. Radiative corrections to the Dalitz plot of charged and neutral baryon semileptonic decays with angular correlation between polarized emitted baryons and charged lepton

    International Nuclear Information System (INIS)

    Because of the near future work of the NA48 experimental group, we have calculated the radiative corrections (RC) to the Dalitz plot of baryon semileptonic decays with angular correlation between polarized emitted baryons and charged leptons. This work covers the two cases, charged and neutral decaying baryons, and it is restricted to the so called three body region of the Dalitz plot. Also it is specialized at the c.m. frame of the emitted baryon. We consider terms up to (α/ product )(q/M1)0, where q is the momentum transfer and M1 is the mass of the decaying baryon, and neglect terms of the order (α/ product )(q/M1)n, n = 1,2,.... The analytical expressions displayed are ready to obtain numerical results, suitable for a model-independent experimental analysis

  7. Upper limits on the production rate of the decuplet baryons delta and Σsup(*) in e+e- annihilation at 34.4 GeV

    International Nuclear Information System (INIS)

    Samples of approx.= 1900 identified protons and approx.= 500 Λ have been used to search for decuplet baryon production in e+e- annihilation at a c.m. energy of 34.4 GeV. The pπ+ and Λπsup(+-) invariant mass spectra contain no Δ or Σsup(*) signals. Upper limits, at 95% confidence level, are that less than 12% of all p and less than 26% of all Λ come from the decay of doubly charged Δ and singly charged Σsup(*) states respectively. These limits correspond to production rates of ++ and ++ and Σsup(*+-) is suppressed by a factor > or approx. 9 relative to octet baryons of the same strangeness. (orig.)

  8. Upper limits on the production rate of the decuplet baryons Δ and Σsup(*) in e+e- annihilation at 34.4 GeV

    International Nuclear Information System (INIS)

    Samples of proportional1,900 identified protons and proportional500 Λ have been used to search for decuplet baryon production in e+e- annihilation at a c.m. energy of 34.4 GeV. The pπ4 and Λπsup(+-) invariant mass spectra contain no Δ or Σsup(*) signals. Upper limits, at 95% confidence level, are that less than 12% of all p and less than 26% of all Λ come from the decay of doubly charged Δ and singly charged Σsup(*) states respectively. These limits correspond to production rates of ++ and ++ and Σsup(*+-) is suppressed by a factor > or approx.9 relative to octet baryons of the same strangeness. (orig.)

  9. Comparison of MALDI-TOF mass spectra of [PdCl(dien]Cl and [Ru(en2Cl2]Cl acquired with different matrices

    Directory of Open Access Journals (Sweden)

    Damnjanović Bojana

    2011-01-01

    Full Text Available In this work, the matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF mass spectra of two cationic complexes, i.e., [PdCl(dien]Cl and [Ru(en2Cl2]Cl, acquired under different conditions were analyzed. The spectra were recorded with three matrices with or without trifluoroacetic acid (TFA, i.e., two traditional matrices, i.e., 2,5-dihydroxybenzoic acid and α-cyano-hydroxycinnamic acid, and one flavonoid, quercetin. The spectra acquired with quercetin appeared to be the simplest, whereas in the spectra obtained with other matrices, peaks arising either from the addition of matrix molecules or from the fragmentation products were detectable. Addition of TFA did not complicate the spectra of the Pd(II and Ru(III complexes when the traditional matrices were used. On the other hand, the spectra of Pd complex were simpler, whereas the addition of TFA in the case of the Ru complex resulted in a higher number of peaks, some of which could not be identified. Taken together, the results of this study once more emphasize the differences arising in the MALDI-TOF mass spectra of transition metal complexes in dependence on the applied matrix.

  10. New characteristics of submicron aerosols and factor analysis of combined organic and inorganic aerosol mass spectra during winter in Beijing

    Science.gov (United States)

    Zhang, J. K.; Ji, D. S.; Liu, Z. R.; Hu, B.; Wang, L. L.; Huang, X. J.; Wang, Y. S.

    2015-07-01

    In recent years, an increasing amount of attention has been paid to heavy haze pollution in Beijing, China. In addition to Beijing's population of approximately 20 million and its 5 million vehicles, nearby cities and provinces are host to hundreds of heavily polluting industries. In this study, a comparison between observations in January 2013 and January 2014 showed that non-refractory PM1 (NR-PM1) pollution was weaker in January 2014, which was primarily caused by variations in meteorological conditions. For the first time, positive matrix factorization (PMF) was applied to the merged high-resolution mass spectra of organic and inorganic aerosols from aerosol mass spectrometer measurements in Beijing, and the sources and evolution of NR-PM1 in January 2014 were investigated. The two factors, NO3-OA1 and NO3-OA2, were primarily composed of ammonium nitrate, and each showed a different degree of oxidation and diurnal variation. The organic fraction of SO4-OA showed the highest degree of oxidation of all PMF factors. The hydrocarbon-like organic aerosol (OA) and cooking OA factors contained negligible amounts of inorganic species. The coal combustion OA factor contained a high contribution from chloride in its mass spectrum. The NR-PM1 composition showed significant variations in January 2014, in which the contribution of nitrate clearly increased during heavy pollution events. The most effective way to control fine particle pollution in Beijing is through joint prevention and control measures at the regional level, rather than a focus on an individual city, especially for severe haze events.

  11. A new method to quantify the effects of baryons on the matter power spectrum

    CERN Document Server

    Schneider, Aurel

    2015-01-01

    Future large-scale galaxy surveys have the potential to become leading probes for cosmology provided the influence of baryons on the total mass distribution is understood well enough. As hydrodynamical simulations strongly depend on details in the feedback implementations, no unique and robust predictions for baryonic effects currently exist. In this paper we propose a baryonic correction model that modifies the density field of dark-matter-only $N$-body simulations to mimic the effects of baryons from any underlying adopted feedback recipe. The model assumes haloes to consist of 4 components: 1- hot gas in hydrostatical equilibrium, 2- ejected gas from feedback processes, 3- central galaxy stars, and 4- adiabatically relaxed dark matter, which all modify the initial dark-matter-only density profiles. This altered mass profiles allow to define a displacement field for particles in $N$-body simulations and to modify the total density field accordingly. The main advantage of the baryonic correction model is to ...

  12. Rosetta/COSIMA: Laboratory time-of-flight secondary ion mass spectra of PAHs for in-situ detection in the cometary solid organic matter

    Science.gov (United States)

    Bardyn, A.; Briois, C.; Cottin, H.; Fray, N.; LeRoy, L.; Thirkell, L.; Hilchenbach, M.

    2014-07-01

    ESA's spacecraft called ROSETTA will reach the comet 67P/Churyumov- Gerasimenko in August 2014. During the escort phase of the mission, beginning after the lander (Philae) is released, the COmetary Secondary Ion Mass Analyzer (COSIMA) [1] carried on board will collect and analyse dust grains in the cometary coma. COSIMA is a time-of-flight secondary ion mass spectrometer (TOF-SIMS) with a high mass resolution m/Δ m of 1400 at mass m=100 amu (from FWHM) and mass range from 1 to 3500 amu. The investigations performed by COSIMA on solid cometary grains are aimed to analyze in situ their molecular, elemental, and isotopic composition. The spectra obtained with COSIMA, will be a combination of mass peaks of mineral and organic elements. The organics are expected to be minor peaks, making their identification not simple. To prepare for the future COSIMA spectra interpretation, the COSIMA team members have started to establish a library database of standardized mass spectra [2,3]. High statistics of positive and negative spectra of the samples were then taken in order to get molecular structure information. Polycyclic Aromatic Hydrocarbons (PAHs) are organic macromolecules that could survive harsh radiation environment. They are suspected to be responsible for unidentified infrared bands observed in diverse astrophysical environments. Many attempts were made to demonstrate the presence of PAHs in comets. Tentative attributions of fluorescence emission bands have been made of spectra taken during the Vega-2 mission [4,5], and recently on Stardust samples returned [6]. In this work, we have used the COSIMA prototype based in Orléans to analyze PAHs and alkanes molecules deposition on gold targets.

  13. Magnetic Moment Formulas of Baryons Determined by Quantum Numbers

    OpenAIRE

    Chang, Yi-Fang

    2008-01-01

    We propose that the magnetic moment formulas of baryons may be determined by quantum numbers, and obtain three formulas. This is a new type of magnetic moment formula, and agrees better with the experimental values. It is also similar to corresponding mass formulas of hadrons.

  14. First observation of doubly charmed baryons

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Moinester et al.

    2003-09-25

    The SELEX experiment (E781) at Fermilab has observed two statistically compelling high mass states near 3.6 GeV/c{sup 2}, decaying to {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +} and {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +}{pi}{sup +}. These final states are Cabibbo-allowed decay modes of doubly charmed baryons {Xi}{sub cc}{sup +} and {Xi}{sub cc}{sup ++}, respectively. The masses are in the range expected from theoretical considerations, but the spectroscopy is surprising. SELEX also has weaker preliminary evidence for a state near 3.8 GeV/c{sup 2}, a high mass state decaying to {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +}{pi}{sup +}, possibly an excited {Xi}{sub cc}{sup ++} (ccu*). Data are presented and discussed.

  15. Baryon Loaded Relativistic Blastwaves in Supernovae

    CERN Document Server

    Chakraborti, Sayan

    2010-01-01

    We provide a new analytic blastwave solution which generalizes the Blandford-McKee solution to arbitrary ejecta masses and Lorentz factors. Until recently relativistic supernovae have been discovered only through their association with long duration Gamma Ray Bursts (GRB). The blastwaves of such explosions are well described by the Blandford-McKee (in the ultra relativistic regime) and Sedov-Taylor (in the non-relativistic regime) solutions during their afterglows, as the ejecta mass is negligible in comparison to the swept up mass. The recent discovery of the relativistic supernova SN 2009bb, without a detected GRB, opens up the possibility of highly baryon loaded mildly relativistic outflows which remains in nearly free expansion phase during the radio afterglow. In this work, we consider a massive, relativistic shell, launched by a Central Engine Driven EXplosion (CEDEX), decelerating due to its collision with the pre-explosion circumstellar wind of the progenitor. We compute the synchrotron emission from ...

  16. Observation of excited $\\Lambda^0_b$ baryons

    CERN Document Server

    Aaij, R; Adametz, A; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Beddow, J; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Corti, G; Couturier, B; Cowan, G A; Craik, D; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Esperante Pereira, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauld, R; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hoballah, M; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li, Y; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Mac Raighne, A; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McCarthy, J; McGregor, G; McNulty, R; Meissner, M; Merk, M; Merkel, J; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen-Mau, C; Nicol, M; Niess, V; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palacios, J; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pie Valls, B; Pietrzyk, B; Pilař, T; Pinci, D; Plackett, R; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodrigues, F; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Rosello, M; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sanmartin Sedes, B; Sannino, M; 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    2012-01-01

    Using $pp$ collision data corresponding to 1.0~fb^{-1} integrated luminosity collected by the LHCb detector, two narrow states are observed in the $\\Lambda_b^0\\pi^+\\pi^-$ spectrum with masses $5911.95\\pm 0.12(\\mbox{stat})\\pm 0.03(\\mbox{syst})\\pm 0.66(\\Lambda_b^0\\mbox{ mass})$ MeV/$c^2$ and $5919.76\\pm 0.07(\\mbox{stat})\\pm 0.02(\\mbox{syst})\\pm 0.66(\\Lambda_b^0\\mbox{ mass})$ MeV/$c^2$. The significances of the observations are 4.9 and 10.1 standard deviations, respectively. These states are interpreted as the orbitally-excited $\\Lambda_b^0$ baryons, $\\Lambda_b^{*0}(5912)$ and $\\Lambda_b^{*0}(5920)$.

  17. Quantifying the effect of baryon physics on weak lensing tomography

    CERN Document Server

    Semboloni, Elisabetta; Schaye, Joop; van Daalen, Marcel P; McCarthy, Ian J

    2011-01-01

    We use matter power spectra from cosmological hydrodynamic simulations to quantify the effect of baryon physics on the weak gravitational lensing shear signal. The simulations consider a number of processes, such as radiative cooling, star formation, supernovae and feedback from active galactic nuclei (AGN). Van Daalen et al. (2011) used the same simulations to show that baryon physics, in particular the strong feedback that is required to solve the overcooling problem, modifies the matter power spectrum on scales relevant for cosmological weak lensing studies. As a result, the use of power spectra from dark matter simulations can lead to significant biases in the inferred cosmological parameters. We show that the typical biases are much larger than the precision with which future missions aim to constrain the dark energy equation of state, w_0. For instance, the simulation with AGN feedback, which reproduces X-ray and optical properties of groups of galaxies, gives rise to a ~40% bias in w_0. We demonstrate ...

  18. The effect of antisymmetrization in diquark models of baryons

    International Nuclear Information System (INIS)

    The effect of antisymmetrization in diquark models of baryons composed of light (u and d) quarks is investigated. The diquark in this study is considered alternately as a point-like and as a composite particle where antisymmetrization is taken into account by means of Generator Coordinate Model operator kernels. The effect on ground state masses and form factors is striking and we are able to conclude that there is a strong dynamical effect due to the presence of antisymmetrization in diquark models of baryon. (author)

  19. Baryon Asymmetry, Dark Matter, and Density Perturbation from PBH

    CERN Document Server

    Fujita, Tomohiro; Harigaya, Keisuke; Matsuda, Ryo

    2014-01-01

    We investigate the consistency of a scenario in which the baryon asymmetry, dark matters, as well as the cosmic density perturbation are generated simultaneously through the evaporation of primordial black holes (PBHs). This scenario can explain the coincidence of the dark matter and the baryon density of the universe, and is free from the isocurvature perturbation problem. We show that this scenario predicts the masses of PBHs, right-handed neutrinos and dark matters, the Hubble scale during inflation, the non-gaussianity and the running of the spectral index. We also discuss the testability of the scenario by detecting high frequency gravitational waves from PBHs.

  20. The hidden charm pentaquarks are the hidden color-octet $uud$ baryons?

    CERN Document Server

    Takeuchi, Sachiko

    2016-01-01

    The $I(J^P)={1\\over 2}({1\\over 2}^-)$, ${1\\over 2}({3\\over 2}^-)$, and ${1\\over 2}({5\\over 2}^-)$ $uudc\\overline{c}$ pentaquarks are investigated by the quark cluster model. This model, which reproduces the mass spectra of the color-singlet $S$-wave $q^3$ baryons and $q\\overline{q}$ mesons, also enables us to evaluate the quark interaction in the color-octet $uud$ configurations. It is shown that the color-octet isospin-${1\\over 2}$ spin-${3\\over 2}$ $uud$ configuration gains attraction. The $uudc\\overline{c}$ states with this configuration cause structures around the $\\Sigma_c{}^{(*)}\\overline{D}{}^{(*)}$ thresholds: one bound state, two resonances, and one large cusp are found. We argue that the negative parity pentaquark found by the LHCb experiments may be given by these structures.