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Sample records for dense matter wdm

  1. DPIS for warm dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, K.; Kanesue, T.; Horioka, K.; Okamura, M.

    2010-05-23

    Warm Dense Matter (WDM) offers an challenging problem because WDM, which is beyond ideal plasma, is in a low temperature and high density state with partially degenerate electrons and coupled ions. WDM is a common state of matter in astrophysical objects such as cores of giant planets and white dwarfs. The WDM studies require large energy deposition into a small target volume in a shorter time than the hydrodynamical time and need uniformity across the full thickness of the target. Since moderate energy ion beams ({approx} 0.3 MeV/u) can be useful tool for WDM physics, we propose WDM generation using Direct Plasma Injection Scheme (DPIS). In the DPIS, laser ion source is connected to the Radio Frequency Quadrupole (RFQ) linear accelerator directly without the beam transport line. DPIS with a realistic final focus and a linear accelerator can produce WDM.

  2. Frontiers and challenges in warm dense matter

    CERN Document Server

    Desjarlais, Michael; Redmer, Ronald; Trickey, Samuel

    2014-01-01

    Warm Dense Matter (WDM) occupies a loosely defined region of phase space intermediate between solid, liquid, gas, and plasma, and typically shares characteristics of two or more of these phases. WDM is generally associated with the combination of strongly coupled ions and moderately degenerate electrons, and careful attention to quantum physics and electronic structure is essential. The lack of a small perturbation parameter greatly limits approximate attempts at its accurate description. Since WDM resides at the intersection of solid state and high energy density physics, many high energy density physics (HEDP) experiments pass through this difficult region of phase space. Thus, understanding and modeling WDM is key to the success of experiments on diverse facilities. These include the National Ignition Campaign centered on the National Ignition Facility (NIF), pulsed-power driven experiments on the Z machine, ion-beam-driven WDM experiments on the NDCX-II, and fundamental WDM research at the Linear Coherent...

  3. Ion-beam-driven warm dense matter experiments

    Science.gov (United States)

    Bieniosek, F. M.; Barnard, J. J.; Friedman, A.; Henestroza, E.; Jung, J. Y.; Leitner, M. A.; Lidia, S.; Logan, B. G.; More, R. M.; Ni, P. A.; Roy, P. K.; Seidl, P. A.; Waldron, W. L.

    2010-08-01

    As a technique for heating matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition to a relatively large sample. The US heavy ion fusion science program has developed techniques for heating and diagnosing warm dense matter (WDM) targets. We have developed a WDM target chamber and a suite of target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments heat targets by both the compressed and uncompressed parts of the NDCX-I beam, and explore measurement of temperature, droplet formation and other target parameters. Continued improvements in beam tuning, bunch compression, and other upgrades are expected to yield higher temperature and pressure in the WDM targets. Future experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  4. Warm Dense Matter: An Overview

    Energy Technology Data Exchange (ETDEWEB)

    Kalantar, D H; Lee, R W; Molitoris, J D

    2004-04-21

    This document provides a summary of the ''LLNL Workshop on Extreme States of Materials: Warm Dense Matter to NIF'' which was held on 20, 21, and 22 February 2002 at the Wente Conference Center in Livermore, CA. The warm dense matter regime, the transitional phase space region between cold material and hot plasma, is presently poorly understood. The drive to understand the nature of matter in this regime is sparking scientific activity worldwide. In addition to pure scientific interest, finite temperature dense matter occurs in the regimes of interest to the SSMP (Stockpile Stewardship Materials Program). So that obtaining a better understanding of WDM is important to performing effective experiments at, e.g., NIF, a primary mission of LLNL. At this workshop we examined current experimental and theoretical work performed at, and in conjunction with, LLNL to focus future activities and define our role in this rapidly emerging research area. On the experimental front LLNL plays a leading role in three of the five relevant areas and has the opportunity to become a major player in the other two. Discussion at the workshop indicated that the path forward for the experimental efforts at LLNL were two fold: First, we are doing reasonable baseline work at SPLs, HE, and High Energy Lasers with more effort encouraged. Second, we need to plan effectively for the next evolution in large scale facilities, both laser (NIF) and Light/Beam sources (LCLS/TESLA and GSI) Theoretically, LLNL has major research advantages in areas as diverse as the thermochemical approach to warm dense matter equations of state to first principles molecular dynamics simulations. However, it was clear that there is much work to be done theoretically to understand warm dense matter. Further, there is a need for a close collaboration between the generation of verifiable experimental data that can provide benchmarks of both the experimental techniques and the theoretical capabilities

  5. Novel OSNR Monitoring Technique in Dense WDM Systems using Inherently Generated CW Monitoring Channels

    DEFF Research Database (Denmark)

    Petersen, Martin Nordal

    2007-01-01

    We present a simple, yet effective OSNR monitoring technique based on an inherent effect in the optical modulator. Highly accurate OSNR monitoring is demonstrated in a 40 Gb/s dense WDM system with 50 GHz channel spacing....

  6. Ion Beam Driven Warm Dense Matter Experiments

    Science.gov (United States)

    Bieniosek, F. M.; Henestroza, E.; Leitner, M. A.; Lidia, S. M.; Logan, B. G.; More, R. M.; Ni, P. A.; Seidl, P. A.; Waldron, W. L.; Barnard, J. J.

    2008-11-01

    We report plans and experimental results in ion beam-driven warm dense matter (WDM) experiments. Initial experiments use a 0.3 MeV K+ beam from the NDCX-I accelerator. The WDM conditions are to be achieved by longitudinal and transverse neutralized drift compression to provide a hot spot on the target with a 1-mm beam spot size, and 2-ns pulse length. As a technique for heating matter to high energy density, intense ion beams can deliver precise and uniform beam energy deposition, in a relatively large sample size, and can heat any solid-phase target material. The range of the beams in solid targets is less than 1 micron, which can be lengthened by using reduced density porous targets. We have developed a WDM target chamber and target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial experiments will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  7. Measurement on Spot Size Dependence of Dense WDM Dielectric Multilayer Filters

    Institute of Scientific and Technical Information of China (English)

    Masanobu; Ito; Satoshi; Suda; Fumio; Koyama

    2003-01-01

    We present the spot size dependence of dielectric multilayer filters for use in dense WDM systems. We found large dependences of filter performances on the spot size and the incident angle of input light, which should be important for miniaturizing multi-channel add/drop filters.

  8. Hyperons in dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Dapo, Haris

    2009-01-28

    The hyperon-nucleon YN low momentum effective interaction (V{sub low} {sub k}) allows for an extensive study of the behavior of hyperons in dense matter, together with an investigation of effects of the presence of hyperons on dense matter. The first step towards this goal is the construction of the matrix elements for the hyperon-nucleon low momentum potential. In order to assess the different properties of hyperons within these potentials we calculate the hyperon single-particle potentials in the Hartree-Fock approximation for all of the interactions. Their dependence on both momentum and density, is studied. The single-particle potentials are then used to determine the chemical potential of hyperons in neutron stars. For nucleonic properties, the nucleon-nucleon V{sub low} {sub k} can be used with the caveat that the calculation of the ground-state energy of symmetric nuclear matter does not correctly reproduce the properties of matter at saturation. With the nucleon-nucleon V{sub low} {sub k} one is unable to reach the densities needed for the calculation of neutron star masses. To circumvent this problem we use two approaches: in the first one, we parametrize the entire nucleonic sector. In the second one, we replace only the three-body force. The former will enable us to study neutron star masses, and the latter for studying the medium's response to the external probe. In this thesis we take the external probe to be the neutrino. By combining this parametrization with the YN V{sub low} {sub k} potential, we calculate the equation of state of equilibrated matter. Performing the calculation in the Hartree-Fock approximation at zero temperature, the concentrations of all particles are calculated. From these we can ascertain at which densities hyperons appear for a wide range of parameters. Finally, we calculate the masses of neutron stars with these concentrations. For the calculation of the medium's response to an external probe, we replace the three

  9. Supporting IP dense mode multicast routing protocols in WDM all-optical networks

    Science.gov (United States)

    Salvador, Marcos R.; Heemstra de Groot, Sonia; Dey, Diptish

    2000-09-01

    Recent developments in all-optical networking and wavelength division multiplexing technologies allow for the support of optical multicasting, a missing feature towards the optical Internet. In this paper we propose a protocol to construct source-rooted WDM multicast trees. The protocol works under dense mode multicasting routing IP protocols and supports network nodes with different degrees of light splitting, wavelength conversion, and add/drop capabilities.

  10. Heavy mesons in dense matter

    NARCIS (Netherlands)

    Tolos, Laura; Gamermann, Daniel; Garcia-Recio, Carmen; Molina, Raquel; Nieves, Juan; Oset, Eulogio; Ramos, Angels; LlanesEstrada, FJ; Pelaez,

    2011-01-01

    Charmed mesons in dense matter are studied within a unitary coupled-channel approach which takes into account Pauli-blocking effects and meson self-energies in a self-consistent manner. We obtain the open-charm meson spectral functions in this dense medium, and discuss their implications on hidden c

  11. The generation of warm dense matter samples using pulsed-power generators

    Science.gov (United States)

    Gourdain, P. A.; Seyler, C. E.; Knapp, P. F.

    2016-10-01

    Warm dense matter (WDM) bridges the gap between plasma and condensed matter, with densities similar to that of a solid, but temperature on the order of 1 eV. WDM is key to understanding the formation of gaseous giants, Mega-Earths, planetary collisions and inertial fusion implosions. Yet, the quantum properties of WDM and how they are expressed at the macroscopic level are mostly unknown. This paper uses 3-dimensional numerical simulations to show that cm-scale WDM samples can be generated by pulsed-power machines using a fast plasma closing switch, which virtually eliminates the mixing of WDM with other states of matter, allowing the measurement of its physical properties using line average diagnostics. A pre-ionized gas puff is imploded onto a central metal rod. Initially, most of the discharge current flows inside the gas shell. When the shell reaches the rod the full current switches to the rod in less than 10 ns. The subsequent compression produces WDM. We will discuss how an existing platform to generate cm-scale WDM at 20MA on the Z-machine at Sandia National Laboratories. This research is sponsored by DOE.

  12. Ab initio thermodynamic results for warm dense matter

    Science.gov (United States)

    Bonitz, Michael

    2016-10-01

    Warm dense matter (WDM) - an exotic state where electrons are quantum degenerate and ions may be strongly correlated - is ubiquitous in dense astrophysical plasmas and highly compressed laboratory systems including inertial fusion. Accurate theoretical predictions require precision thermodynamic data for the electron gas at high density and finite temperature around the Fermi temperature. First such data have been obtained by restricted path integral Monte Carlo (restricted PIMC) simulations and transformed into analytical fits for the free energy. Such results are also key input for novel finite temperature density functional theory. However, the RPIMC data of Ref. 1 are limited to moderate densities, and even there turned out to be surprisingly inaccurate, which is a consequence of the fermion sign problem. These problems were recently overcome by the development of alternative QMC approaches in Kiel (configuration PIMC and permutation blocking PIMC) and Imperial College (Density matrix QMC). The three methods have their strengths and limitations in complementary parameter regions and provide highly accurate thermodynamic data for the electronic contributions in WDM. While the original results were obtained for small particle numbers, recently accurate finite size corrections were derived allowing to compute ab initio thermodynamic data with an unprecedented accuracy of better than 0.3 percent. This provides the final step for the use as benchmark data for experiments and models of Warm dense matter. Co-authors: T. Schoof, S. Groth, T. Dornheim, F. D. Malone, M. Foulkes, and T. Sjostroem, Funded by: DFG via SFB-TR24 and project BO1366-10.

  13. Dilatons for Dense Hadronic Matter

    CERN Document Server

    Lee, Hyun Kyu

    2009-01-01

    The idea that the explicit breaking of scale invariance by the trace anomaly of QCD can be rephrased as a spontaneous breaking has been recently exploited to capture the low-energy strong interaction dynamics of dense (and also hot) matter in terms of two dilaton fields, the "soft" (chi_s) and the "hard" (chi_h) fields, in the frame work of the hidden local gauge symmetry. In the Freund-Nambu model, the spontaneous symmetry breaking of scale symmetry is induced by an explicitly breaking term, while the spontaneous symmetry breaking is possible in the flat potential model which is scale symmetric. We discuss the interplay of the soft and hard dilatons using the spontaneously broken scale symmetry schemes and uncover a novel structure of dense matter hitherto unexplored.

  14. Dilatons in Dense Baryonic Matter

    CERN Document Server

    Lee, Hyun Kyu

    2013-01-01

    We discuss the role of dilaton, which is supposed to be representing a special feature of scale symmetry of QCD, trace anomaly, in dense baryonic matter. The idea that the scale symmetry breaking of QCD is responsible for the spontaneous breaking of chiral symmetry is presented along the similar spirit of Freund-Nambu model. The incorporation of dilaton field in the hidden local symmetric parity doublet model is briefly sketched with the possible role of dilaton at high density baryonic matter, the emergence of linear sigma model in dilaton limit.

  15. Input energy measurement toward warm dense matter generation using intense pulsed power generator

    Science.gov (United States)

    Hayashi, R.; Ito, T.; Ishitani, T.; Tamura, F.; Kudo, T.; Takakura, N.; Kashine, K.; Takahashi, K.; Sasaki, T.; Kikuchi, T.; Harada, Nob.; Jiang, W.; Tokuchi, A.

    2016-05-01

    In order to investigate properties of warm dense matter (WDM) in inertial confinement fusion (ICF), evaluation method for the WDM with isochoric heating on the implosion time-scale using an intense pulsed power generator ETIGO-II (∼1 TW, ∼50 ns) has been considered. In this study, the history of input energy into the sample is measured from the voltage and the current waveforms. To achieve isochoric heating, a foamed aluminum with pore sizes 600 μm and with 90% porosity was packed into a hollow glass capillary (ø 5 mm × 10 mm). The temperature of the sample is calculated from the numerical calculation using the measured input power. According to the above measurements, the input energy into a sample and the achievable temperature are estimated to be 300 J and 6000 K. It indicates that the WDM state is generated using the proposed method with ICF implosion time-scale.

  16. Neutrino Oscillations in Dense Matter

    Science.gov (United States)

    Lobanov, A. E.

    2017-03-01

    A modification of the electroweak theory, where the fermions with the same electroweak quantum numbers are combined in multiplets and are treated as different quantum states of a single particle, is proposed. In this model, mixing and oscillations of particles arise as a direct consequence of the general principles of quantum field theory. The developed approach enables one to calculate the probabilities of the processes taking place in the detector at long distances from the particle source. Calculations of higher-order processes, including computation of the contributions due to radiative corrections, can be performed in the framework of the perturbation theory using the regular diagram technique. As a result, the analog to the Dirac-Schwinger equation of quantum electrodynamics describing neutrino oscillations and its spin rotation in dense matter can be obtained.

  17. Restricted Path-Integral Molecular Dynamics for Simulating the Correlated Electron Plasma in Warm Dense Matter

    Science.gov (United States)

    Kapila, Vivek; Deymier, Pierre; Runge, Keith

    2011-10-01

    Several areas of study including heavy ion beam, large scale laser, and high pressure or Thomson scattering studies necessitate a fundamental understanding of warm dense matter (WDM) i.e. matter at high temperature and high density. The WDM regime, however, lacks any adequate highly developed class of simulation methods. Recent progress to address this deficit has been the development of orbital-free Density Functional Theory (ofDFT). However, scant benchmark information is available on temperature and pressure dependence of simple but realistic models in WDM regime. The present work aims to fill this critical gap using the restricted path-integral molecular dynamics (rPIMD) method. Within the discrete path integral representation, electrons are described as harmonic necklaces. Quantum exchange takes the form of cross linking between electron necklaces. The fermion sign problem is addressed by restricting the density matrix to positive values. The molecular dynamics algorithm is employed to sample phase space. Here, we focus on the behavior of strongly correlated electron plasmas under WDM conditions. We compute the kinetic and potential energies and compare them to those obtained with the ofDFT method. Several areas of study including heavy ion beam, large scale laser, and high pressure or Thomson scattering studies necessitate a fundamental understanding of warm dense matter (WDM) i.e. matter at high temperature and high density. The WDM regime, however, lacks any adequate highly developed class of simulation methods. Recent progress to address this deficit has been the development of orbital-free Density Functional Theory (ofDFT). However, scant benchmark information is available on temperature and pressure dependence of simple but realistic models in WDM regime. The present work aims to fill this critical gap using the restricted path-integral molecular dynamics (rPIMD) method. Within the discrete path integral representation, electrons are described as

  18. Dense all-optical WDM-SCM technology for high-speed computer interconnects

    Science.gov (United States)

    Ih, Charles S.; Tian, Rongsheng; Zhou, H. X.; Xia, Xiang-Gen

    1993-07-01

    We describe a dense and flexible all optical multi-channel communication system for high speed computer interconnects. The system can provide 10 Gb/s for each individual node with a total system capacity to 250 Gb/s using currently available technologies. The system capacity can be scaled to 1 Tb/s using optical amplifiers with a broader bandwidth and higher modulations. The system is based on the multi-beam (heterodyne) modulator (MBM) recently demonstrated in our laboratory and other current technologies in tunable laser arrays and acousto-optical tunable filter (AOTF). Each MBM automatically forms a high frequency microwave sub-carrier multiplexing (SCM) with sub-carrier frequency to tens of GHz. A MBM with sub-carriers at 17 and 21 GHz has already been demonstrated and can be scaled to higher frequencies by using a higher frequency detector. Each SCM group may consist of up to 10 one-Gb/s channels and occupies only 1 nm spectral width. Therefore we can form a conventional WDM with 25 divisions within the bandwidth of commercially available optical amplifiers.

  19. Calculations on the stopping power of a heterogeneous Warm Dense Matter

    CERN Document Server

    Casas, David; Schnürer, Matthias; Barriga-Carrasco, Manuel D; Morales, Roberto; González-Gallego, Luis

    2015-01-01

    The stopping power of Warm Dense Matter (WDM) is estimated by means of the individual contributions of free electrons and bound electrons existing in this special kind of matter, located between classical and degenerate plasmas. For free electrons, the dielectric formalism, well described in previous works of our research group, is used to estimate free electron stopping power. For bound electrons, mean excitation energy of ions is used. Excitation energies are obtained through atomic calculations of the whole atom or, shell by shell in order to estimate their stopping power. Influence of temperature and density is analyzed in case of an impinging projectile. This influence became important for low projectile velocities and negligible for high ones. Using both analysis, the stopping power of an extended WDM is inferred from a dynamical calculation of energy transferred from the projectile to the plasma, where the Bragg peak and stopping range are calculated. Finally, this theoretical framework is used to stud...

  20. Heavy meson production in hot dense matter

    NARCIS (Netherlands)

    Tolos, Laura; Gamermann, Daniel; Garcia-Recio, Carmen; Molina, Raquel; Nieves, Juan; Oset, Eulogio; Ramos, Angels; Nieves, JM; Oset, E; Vacas, MJV

    2010-01-01

    The properties of charmed mesons in dense matter are studied using a unitary coupled-channel approach in the nuclear medium which takes into account Pauli-blocking effects and meson self-energies in a self-consistent manner. We obtain the open-charm meson spectral functions in this dense nuclear env

  1. Probing Cold Dense Nuclear Matter

    Energy Technology Data Exchange (ETDEWEB)

    Subedi, Ramesh; Shneor, R.; Monaghan, Peter; Anderson, Bryon; Aniol, Konrad; Annand, John; Arrington, John; Benaoum, Hachemi; Benmokhtar, Fatiha; Bertozzi, William; Boeglin, Werner; Chen, Jian-Ping; Choi, Seonho; Cisbani, Evaristo; Craver, Brandon; Frullani, Salvatore; Garibaldi, Franco; Gilad, Shalev; Gilman, Ronald; Glamazdin, Oleksandr; Hansen, Jens-Ole; Higinbotham, Douglas; Holmstrom, Timothy; Ibrahim, Hassan; Igarashi, Ryuichi; De Jager, Cornelis; Jans, Eddy; Jiang, Xiaodong; Kaufman, Lisa; Kelleher, Aidan; Kolarkar, Ameya; Kumbartzki, Gerfried; LeRose, John; Lindgren, Richard; Liyanage, Nilanga; Margaziotis, Demetrius; Markowitz, Pete; Marrone, Stefano; Mazouz, Malek; Meekins, David; Michaels, Robert; Moffit, Bryan; Perdrisat, Charles; Piasetzky, Eliazer; Potokar, Milan; Punjabi, Vina; Qiang, Yi; Reinhold, Joerg; Ron, Guy; Rosner, Guenther; Saha, Arunava; Sawatzky, Bradley; Shahinyan, Albert; Sirca, Simon; Slifer, Karl; Solvignon, Patricia; Sulkosky, Vince; Sulkosky, Vincent; Sulkosky, Vince; Sulkosky, Vincent; Urciuoli, Guido; Voutier, Eric; Watson, John; Weinstein, Lawrence; Wojtsekhowski, Bogdan; Wood, Stephen; Zheng, Xiaochao; Zhu, Lingyan

    2008-06-01

    The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, in which a proton is knocked out of the nucleus with high-momentum transfer and high missing momentum, show that in carbon-12 the neutron-proton pairs are nearly 20 times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars.

  2. Probing Cold Dense Nuclear Matter

    CERN Document Server

    Subedi, R; Monaghan, P; Anderson, B D; Aniol, K; Annand, J; Arrington, J; Benaoum, H; Benmokhtar, F; Bertozzi, W; Boeglin, W; Chen, J -P; Choi, Seonho; Cisbani, E; Craver, B; Frullani, S; Garibaldi, F; Gilad, S; Gilman, R; Glamazdin, O; Hansen, J -O; Higinbotham, D W; Holmstrom, T; Ibrahim, H; Igarashi, R; De Jager, C W; Jans, E; Jiang, X; Kaufman, L; Kelleher, A; Kolarkar, A; Kumbartzki, G; LeRose, J J; Lindgren, R; Liyanage, N; Margaziotis, D J; Markowitz, P; Marrone, S; Mazouz, M; Meekins, D; Michaels, R; Moffit, B; Perdrisat, C F; Piasetzky, E; Potokar, M; Punjabi, V; Qiang, Y; Reinhold, J; Ron, G; Rosner, G; Saha, A; Sawatzky, B; Shahinyan, A; Širca, S; Slifer, K; Solvignon, P; Sulkosky, V; Urciuoli, G; Voutier, E; Watson, J W; Weinstein, L B; Wojtsekhowski, B; Wood, S; Zheng, X -C; Zhu, L; 10.1126/science.1156675

    2009-01-01

    The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, where a proton is knocked-out of the nucleus with high momentum transfer and high missing momentum, show that in 12C the neutron-proton pairs are nearly twenty times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars.

  3. Molecular Dynamics for Dense Matter

    CERN Document Server

    Maruyama, Toshiki; Chiba, Satoshi

    2012-01-01

    We review a molecular dynamics method for nucleon many-body systems called the quantum molecular dynamics (QMD) and our studies using this method. These studies address the structure and the dynamics of nuclear matter relevant to the neutron star crusts, supernova cores, and heavy-ion collisions. A key advantage of QMD is that we can study dynamical processes of nucleon many-body systems without any assumptions on the nuclear structure. First we focus on the inhomogeneous structures of low-density nuclear matter consisting not only of spherical nuclei but also of nuclear "pasta", i.e., rod-like and slab-like nuclei. We show that the pasta phases can appear in the ground and equilibrium states of nuclear matter without assuming nuclear shape. Next we show our simulation of compression of nuclear matter which corresponds to the collapsing stage of supernovae. With increase of density, a crystalline solid of spherical nuclei change to a triangular lattice of rods by connecting neighboring nuclei. Finally, we dis...

  4. Heavy Hadrons in Dense Matter

    CERN Document Server

    Tolos, Laura; Hidalgo-Duque, Carlos; Nieves, Juan; Romanets, Olena; Salcedo, Lorenzo Luis; Torres-Rincon, Juan M

    2015-01-01

    We study the behavior of dynamically-generated baryon resonances with heavy-quark content within a unitarized coupled-channel theory in matter that fulfills heavy-quark spin symmetry constraints. We analyze the implications for the formation of charmed mesic nuclei and the propagation of heavy mesons in heavy-ion collisions from RHIC to FAIR.

  5. Warm Dense Matter Experiments Driven by Ion Beams

    Science.gov (United States)

    Bieniosek, F. M.; Henestroza, E.; Jung, J. Y.; Leitner, M. A.; Lidia, S.; Logan, B. G.; More, R. M.; Ni, P. A.; Roy, P. K.; Seidl, P. A.; Waldron, W. L.; Barnard, J. J.; Friedman, A.

    2009-11-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. We present results from warm dense matter (WDM) experiments at NDCX-I. The 0.3 MeV, 30-mA K^+ beam from the NDCX-I accelerator heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam to a spot size ˜ 1 mm, and compressed pulse length ˜ 2 ns. The uncompressed beam flux is >=500 kW/cm^2, and the compressed pulse flux is > 5 MW/cm^2. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. Future plans include construction of the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-4 MeV lithium ion beam. We have developed a target chamber and target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, and high-speed gated cameras. We compare measurements of temperature, droplet formation and other target parameters with model predictions. Continued improvements in beam tuning, bunch compression, and other upgrades are expected to yield higher flux on target.

  6. Optical diagnostic of warm dense matter at NDCXI

    Science.gov (United States)

    Ni, Pavel; Bieniosek, Frank; Barnard, John; Henestroza, Enrique; Lidia, Steve; More, Dick

    2010-11-01

    This work is related to recently warm dense matter experiments at Lawrence Berkeley National Laboratory (LBNL), Neutralized Drift Compression Experiment (NDCX) accelerator, which delivers a 30-mA, 350-keV K^+ ion beam. Using the recently-developed technique of neutralized drift compression, the beam is simultaneously compressed longitudinally by a factor of 50, and focused transversely down to a 1 mm spot. The beam pulse is used to pulse heat various target materials, including Al, W, C, Pt and Si, above 3000 K driving samples into two-phase, liquid-vapor states. The next generation accelerator, NDCX-II, is being built and scheduled to be accomplished in 2012. This new machine will, utilize 2 MeV Li+ ions, to heat 2 micrometer thick metal targets up to 1,5 eV in 0.5 ns. This will allow us investigate near critical points properties of matter. The talk will focus on diagnostics aspects of WDM at NDCX. The fielded diagnostics include a specially developed three-channel optical pyrometer which probes color temperatures of the target at 750 nm, 1000 nm and 1500 nm, with 75 ps temporal resolution. Continuous target emission from 450 nm to 850 nm is recorded by a custom spectrometer, consisting of a high dynamic range Hamamatsu streak camera and a holographic grating. Free expansion of the sample is measured by a VISAR. Future diagnostics for the NDX-II user facility will be also discussed.

  7. Dense matter at RAON: Challenges and possibilities

    Science.gov (United States)

    Lee, Yujeong; Lee, Chang-Hwan; Gaitanos, T.; Kim, Youngman

    2016-11-01

    Dense nuclear matter is ubiquitous in modern nuclear physics because it is related to many interesting microscopic and macroscopic phenomena such as heavy ion collisions, nuclear structure, and neutron stars. The on-going rare isotope science project in Korea will build up a rare isotope accelerator complex called RAON. One of the main goals of RAON is to investigate rare isotope physics including dense nuclear matter. Using the relativistic Boltzmann-Uehling-Uhlenbeck (RBUU) transport code, we estimate the properties of nuclear matter that can be created from low-energy heavyion collisions at RAON.We give predictions for the maximum baryon density, the isospin asymmetry and the temperature of nuclear matter that would be formed during 197Au+197Au and 132Sn+64Ni reactions. With a large isospin asymmetry, various theoretical studies indicate that the critical densities or temperatures of phase transitions to exotic states decrease. Because a large isospin asymmetry is expected in the dense matter created at RAON, we discuss possibilities of observing exotic states of dense nuclear matter at RAON for large isospin asymmetry.

  8. A pulsed power hydrodynamics approach to exploring properties of warm dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Reinovsky, Robert Emil [Los Alamos National Laboratory

    2008-01-01

    Pulsed Power Hydrodynamics, as an application of low-impedance, pulsed power, and high magnetic field technology developed over the last decade to study advanced hydrodynamic problems, instabilities, turbulence, and material properties, can potentially be applied to the study of the behavior and properties of warm dense matter (WDM) as well. Exploration of the properties, such as equation of state and conductivity, of warm dense matter is an emerging area of study focused on the behavior of matter at density near solid density (from 10% of solid density to a few times solid density) and modest temperatures ({approx}1-10 eV). Warm dense matter conditions can be achieved by laser or particle beam heating of very small quantities of matter on timescales short compared to the subsequent hydrodynamic expansion timescales (isochoric heating) and a vigorous community of researchers is applying these techniques using petawatt scale laser systems, but the microscopic size scale of the WDM produced in this way limits access to some physics phenomena. Pulsed power hydrodynamics techniques, either through high convergence liner compression of a large volume, modest density, low temperature plasma to densities approaching solid density or through the explosion and subsequent expansion of a conductor (wire) against a high pressure (density) gas background (isobaric expansion) techniques both offer the prospect for producing warm dense matter in macroscopic quantities. However, both techniques demand substantial energy, proper power conditioning and delivery, and an understanding of the hydrodynamic and instability processes that limit each technique. Similarly, liner compression of normal density material, perhaps using multiple reflected shocks can provide access to the challenging region above normal density -- again with the requirement of very large amounts of driving energy. In this paper we will provide an introduction to techniques that might be applied to explore this

  9. Observations of Plasmons in Warm Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Glenzer, S H; Landen, O L; Neumayer, P; Lee, R W; Widmann, K; Pollaine, S W; Wallace, R J; Gregori, G; Holl, A; Bornath, T; Thiele, R; Schwarz, V; Kraeft, W; Redmer, R

    2006-09-05

    We present the first collective x-ray scattering measurements of plasmons in solid-density plasmas. The forward scattering spectra of a laser-produced narrow-band x-ray line from isochorically heated beryllium show that the plasmon frequency is a sensitive measure of the electron density. Dynamic structure calculations that include collisions and detailed balance match the measured plasmon spectrum indicating that this technique will enable new applications to determine the equation of state and compressibility of dense matter.

  10. Unified first principles description from warm dense matter to ideal ionized gas plasma: electron-ion collisions induced friction.

    Science.gov (United States)

    Dai, Jiayu; Hou, Yong; Yuan, Jianmin

    2010-06-18

    Electron-ion interactions are central to numerous phenomena in the warm dense matter (WDM) regime and at higher temperature. The electron-ion collisions induced friction at high temperature is introduced in the procedure of ab initio molecular dynamics using the Langevin equation based on density functional theory. In this framework, as a test for Fe and H up to 1000 eV, the equation of state and the transition of electronic structures of the materials with very wide density and temperature can be described, which covers a full range of WDM up to high energy density physics. A unified first principles description from condensed matter to ideal ionized gas plasma is constructed.

  11. A single-shot spatial chirp method for measuring initial AC conductivity evolution of femtosecond laser pulse excited warm dense matter

    Science.gov (United States)

    Chen, Z.; Hering, P.; Brown, S. B.; Curry, C.; Tsui, Y. Y.; Glenzer, S. H.

    2016-11-01

    To study the rapid evolution of AC conductivity from ultrafast laser excited warm dense matter (WDM), a spatial chirp single-shot method is developed utilizing a crossing angle pump-probe configuration. The pump beam is shaped individually in two spatial dimensions so that it can provide both sufficient laser intensity to excite the material to warm dense matter state and a uniform time window of up to 1 ps with sub-100 fs FWHM temporal resolution. Temporal evolution of AC conductivity in laser excited warm dense gold was also measured.

  12. Flavour Oscillations in Dense Baryonic Matter

    Science.gov (United States)

    Filip, Peter

    2017-01-01

    We suggest that fast neutral meson oscillations may occur in a dense baryonic matter, which can influence the balance of s/¯s quarks in the nucleus-nucleus and proton-nucleus interactions, if primordial multiplicities of neutral K 0, mesons are sufficiently asymmetrical. The phenomenon can occur even if CP symmetry is fully conserved, and it may be responsible for the enhanced sub-threshold production of multi-strange hyperons observed in the low-energy A+A and p+A interactions.

  13. Intense, ultrashort light and dense, hot matter

    Indian Academy of Sciences (India)

    G Ravindra Kumar

    2009-07-01

    This article presents an overview of the physics and applications of the interaction of high intensity laser light with matter. It traces the crucial advances that have occurred over the past few decades in laser technology and nonlinear optics and then discusses physical phenomena that occur in intense laser fields and their modeling. After a description of the basic phenomena like multiphoton and tunneling ionization, the physics of plasma formed in dense matter is presented. Specific phenomena are chosen for illustration of the scientific and technological possibilities – simulation of astrophysical phenomena, relativistic nonlinear optics, laser wakefield acceleration, laser fusion, ultrafast real time X-ray diffraction, application of the particle beams produced from the plasma for medical therapies etc. A survey of the Indian activities in this research area appears at the end.

  14. 1 Gbps full-duplex links for ultra-dense-WDM 6.25 GHz frequency slots in optical metro-access networks.

    Science.gov (United States)

    Altabas, Jose A; Izquierdo, David; Lazaro, Jose A; Lerin, Adolfo; Sotelo, Felix; Garces, Ignacio

    2016-01-11

    1 Gbps full-duplex optical links for 6.25 GHz ultra dense WDM frequency slots are demonstrated and optimized for cost-effective metro-access networks. The OLT-ONU downlinks are based on 1 Gbps Nyquist-DPSK using MZM and single-detector heterodyne reception obtaining a sensitivity of -52 dBm. The ONU-OLT uplinks are based on 1 Gbps NRZ-DPSK by directly phase modulated DFB and also single-detector heterodyne reception obtaining same sensitivity of -52 dBm. The power budget of full-duplex link is 43 dB. These proposed links can provide service to 16 (32) users at each 100 (200) GHz WDM channel.

  15. Phase Structure and Transport Properties of Dense Quark Matter

    CERN Document Server

    Schaefer, Thomas

    2010-01-01

    We provide a summary of our current knowledge of the phase structure of very dense quark matter. We concentrate on the question how the ground state at asymptotically high density -- color-flavor-locked (CFL) matter -- is modified as the density is lowered. We discuss the nature of the quasi-particle excitations, and present work on the transport properties of dense QCD matter.

  16. The symmetry energy in cold dense matter

    CERN Document Server

    Jeong, Kie Sang

    2015-01-01

    We calculate the symmetry energy in cold dense matter both in the normal quark phase and in the 2-color superconductor (2SC) phase. For the normal phase, the thermodynamic potential is calculated by using hard dense loop (HDL) resummation to leading order, where the dominant contribution comes from the longitudinal gluon rest mass. The effect of gluonic interaction to the symmetry energy, obtained from the thermodynamic potential, was found to be small. In the 2SC phase, the non-perturbative BCS paring gives enhanced symmetry energy as the gapped states are forced to be in the common Fermi sea reducing the number of available quarks that can contribute to the asymmetry. We used high density effective field theory to estimate the contribution of gluon interaction to the symmetry energy. Among the gluon rest masses in 2SC phase, only the Meissner mass has iso-spin dependence although the magnitude is much smaller than the Debye mass. As the iso-spin dependence of gluon rest masses is even smaller than the case ...

  17. Symmetry energy in cold dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kie Sang, E-mail: k.s.jeong@yonsei.ac.kr; Lee, Su Houng, E-mail: suhoung@yonsei.ac.kr

    2016-01-15

    We calculate the symmetry energy in cold dense matter both in the normal quark phase and in the 2-color superconductor (2SC) phase. For the normal phase, the thermodynamic potential is calculated by using hard dense loop (HDL) resummation to leading order, where the dominant contribution comes from the longitudinal gluon rest mass. The effect of gluonic interaction on the symmetry energy, obtained from the thermodynamic potential, was found to be small. In the 2SC phase, the non-perturbative BCS paring gives enhanced symmetry energy as the gapped states are forced to be in the common Fermi sea reducing the number of available quarks that can contribute to the asymmetry. We used high density effective field theory to estimate the contribution of gluon interaction to the symmetry energy. Among the gluon rest masses in 2SC phase, only the Meissner mass has iso-spin dependence although the magnitude is much smaller than the Debye mass. As the iso-spin dependence of gluon rest masses is even smaller than the case in the normal phase, we expect that the contribution of gluonic interaction to the symmetry energy in the 2SC phase will be minimal. The different value of symmetry energy in each phase will lead to different prediction for the particle yields in heavy ion collision experiment.

  18. Quantum molecular dynamics simulations of dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Collins, L.; Kress, J.; Troullier, N.; Lenosky, T.; Kwon, I. [Los Alamos National Lab., Albuquerque, NM (United States)

    1997-12-31

    The authors have developed a quantum molecular dynamics (QMD) simulation method for investigating the properties of dense matter in a variety of environments. The technique treats a periodically-replicated reference cell containing N atoms in which the nuclei move according to the classical equations-of-motion. The interatomic forces are generated from the quantum mechanical interactions of the (between?) electrons and nuclei. To generate these forces, the authors employ several methods of varying sophistication from the tight-binding (TB) to elaborate density functional (DF) schemes. In the latter case, lengthy simulations on the order of 200 atoms are routinely performed, while for the TB, which requires no self-consistency, upwards to 1000 atoms are systematically treated. The QMD method has been applied to a variety cases: (1) fluid/plasma Hydrogen from liquid density to 20 times volume-compressed for temperatures of a thousand to a million degrees Kelvin; (2) isotopic hydrogenic mixtures, (3) liquid metals (Li, Na, K); (4) impurities such as Argon in dense hydrogen plasmas; and (5) metal/insulator transitions in rare gas systems (Ar,Kr) under high compressions. The advent of parallel versions of the methods, especially for fast eigensolvers, presage LDA simulations in the range of 500--1000 atoms and TB runs for tens of thousands of particles. This leap should allow treatment of shock chemistry as well as large-scale mixtures of species in highly transient environments.

  19. Accelerator and Ion Beam Tradeoffs for Studies of Warm Dense Matter

    CERN Document Server

    Barnard, John J; Callahan, Debra; Davidson, Ronald C; Friedman, Alex; Grant-Logan, B; Grisham, Larry; Lee, Edward; Lee, Richard; Olson, Craig; Rose, David; Santhanam, Parthiban; Sessler, Andrew M; Staples, John W; Tabak, Max; Welch, Dale; Wurtele, Jonathan; Yu, Simon

    2005-01-01

    One approach to heat a target to "Warm Dense Matter" conditions (similar, for example, to the interiors of giant planets or certain stages in Inertial Confinement Fusion targets), is to use intense ion beams as the heating source. By consideration of ion beam phase space constraints, both at the injector, and at the final focus, and consideration of simple equations of state, approximate conditions at a target foil may be calculated. Thus target temperature and pressure may be calculated as a function of ion mass, ion energy, pulse duration, velocity tilt, and other accelerator parameters. We examine the variation in target performance as a function of various beam and accelerator parameters, in the context of several different accelerator concepts, recently proposed for WDM studies.

  20. Study of the Warm Dense Matter with XANES spectroscopy - Applications to planetary interiors

    Science.gov (United States)

    Denoeud, Adrien

    With the recent discovery of many exoplanets, modelling the interior of these celestial bodies is becoming a fascinating scientific challenge. In this context, it is crucial to accurately know the equations of state and the macroscopic and microscopic physical properties of their constituent materials in the Warm Dense Matter regime (WDM). Moreover, planetary models rely almost exclusively on physical properties obtained using first principles simulations based on density functional theory (DFT) predictions. It is thus of paramount importance to validate the basic underlying mechanisms occurring for key planetary constituents (metallization, dissociation, structural modifications, phase transitions, etc....) as pressure and temperature both increase. In this work, we were interested in two materials that can be mainly found in the Earth-like planets: silica, or SiO2, as a model compound of the silicates that constitute the major part of their mantles, and iron, which is found in abundance in their cores. These two materials were compressed and brought to the WDM regime by using strong shock created by laser pulses during various experiments performed on the LULI2000 (Palaiseau, France) and the JLF (Livermore, US) laser facilities and on the LCLS XFEL (Stanford, US). In order to penetrate this dense matter and to have access to its both ionic and electronic structures, we have probed silica and iron with time-resolved X-ray Absorption Near Edge Structure (XANES). In parallel with these experiments, we performed quantum molecular dynamics simulations based on DFT at conditions representative of the region investigated experimentally so as to extract the interesting physical processes and comprehend the limits of the implemented models. In particular, these works allowed us to highlight the metallization processes of silica in temperature and the structural changes of its liquid in density, as well as to more constrain the melting curve of iron at very high pressures.

  1. Intense Ion Beam for Warm Dense Matter Physics

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Joshua Eugene [Univ. of California, Berkeley, CA (United States)

    2008-01-01

    The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induction bunching module, beam neutralization section, and final focusing system. The principal objectives of the experiment are to control the beam envelope, demonstrate effective neutralization of the beam space-charge, control the velocity tilt on the beam, and understand defocusing effects, field imperfections, and limitations on peak intensity such as emittance and aberrations. Target heating experiments with space-charge dominated ion beams require simultaneous longitudinal bunching and transverse focusing. A four-solenoid lattice is used to tune the beam envelope to the necessary focusing conditions before entering the induction bunching module. The induction bunching module provides a head-to-tail velocity ramp necessary to achieve peak axial compression at the desired focal plane. Downstream of the induction gap a plasma column neutralizes the beam space charge so only emittance limits the focused beam intensity. We present results of beam transport through a solenoid matching section and simultaneous focusing of a singly charged K+ ion bunch at an ion energy of 0.3 MeV. The results include a qualitative comparison of experimental and calculated results after the solenoid matching section, which include time resolved current density, transverse distributions, and phase-space of the beam at different diagnostic planes. Electron cloud and gas measurements in the solenoid lattice and in the vicinity of intercepting diagnostics are also presented. Finally

  2. Electron-ion and ion-ion potentials for modeling warm-dense-matter: applications to laser-heated or shock-compressed Al and Si

    CERN Document Server

    Dharma-wardana, M W C

    2012-01-01

    The pair-interactions U_{ij}(r) determine the thermodynamics and linear transport properties of matter via the pair-distribution functions (PDFs), i.e., g_{ij}(r). Great simplicity is achieved if U_{ij}(r) could be directly used to predict material properties via classical simulations, avoiding many-body wavefunctions. Warm dense matter (WDM) is encountered in quasi-equilibria where the electron temperature $T_e$ differs from the ion temperature T_i, as in laser-heated or in shock-compressed matter. The electron PDFs g_{ee}(r) as perturbed by the ions are used to evaluate fully non-local exchange-correlation corrections to the free energy, using Hydrogen as an example. Electron-ion potentials for ions with a bound core are discussed with Al and Si as examples, for WDM with T_e \

  3. Pump-probe studies of radiation induced defects and formation of warm dense matter with pulsed ion beams

    Science.gov (United States)

    Schenkel, T.; Persaud, A.; Gua, H.; Seidl, P. A.; Waldron, W. L.; Gilson, E. P.; Kaganovich, I. D.; Davidson, R. C.; Friedman, A.; Barnard, J. J.; Minior, A. M.

    2014-10-01

    We report results from the 2nd generation Neutralized Drift Compression Experiment at Berkeley Lab. NDCX-II is a pulsed, linear induction accelerator designed to drive thin foils to warm dense matter (WDM) states with peak temperatures of ~ 1 eV using intense, short pulses of 1.2 MeV lithium ions. Tunability of the ion beam enables pump-probe studies of radiation effects in solids as a function of excitation density, from isolated collision cascades to the onset of phase-transitions and WDM. Ion channeling is an in situ diagnostic of damage evolution during ion pulses with a sensitivity of channeled ions tracks lattice disorder evolution with a resolution of ~ 1 ns using fast current measurements. We will discuss pump-probe experiments with pulsed ion beams and the development of diagnostics for WDM and multi-scale (ms to fs) access to the materials physics of collision cascades e.g. in fusion reactor materials. Work performed under auspices of the US DOE under Contract No. DE-AC02-05CH11231.

  4. Simulation of the Correlated Electron Plasma in the Warm Dense Matter Regime by Restricted Path-Integral Molecular Dynamics

    Science.gov (United States)

    Kapila, Vivek; Deymier, Pierre; Runge, Keith

    2012-02-01

    Warm dense matter (WDM) can be characterized by electron temperatures of a few eV and densities an order of magnitude or more beyond ambient. This regime currently lacks any adequate highly developed class of simulation methods. Recent developments in orbital-free Density Functional Theory (ofDFT) aim to provide such a simulation method, however, little benchmark information is available on temperature and pressure dependence of simple but realistic models in WDM regime. The present work aims to fill this critical gap using the restricted path-integral molecular dynamics (rPIMD) method. Within the discrete path integral representation, electrons are described as harmonic necklaces, while, quantum exchange takes the form of cross linking between electron necklaces. The fermion sign problem is addressed by restricting the density matrix to positive values and a molecular dynamics algorithm is employed to sample phase space. Here, we focus on the behavior of strongly correlated electron plasmas under WDM conditions. We compute the kinetic and potential energies and compare them to those obtained with the ofDFT method.

  5. Neutrino reactions in hot and dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Lohs, Andreas

    2015-04-13

    In this thesis, neutrino reactions in hot and dense matter are studied. In particular, this work is concerned with neutrino-matter interactions that are relevant for neutrino transport in core-collapse supernovae (CCSNe). The majority of the energy from a CCSN is released in the form of neutrinos. Accurate understanding and computation of these interactions is most relevant to achieve sufficiently reliable predictions for the evolution of CCSNe and other related question such as the production of heavy elements or neutrino oscillations. For this purpose this work follows the combined approach of searching for new important neutrino reactions and improving the computation of those reactions that are already implemented. First we estimate the relevance of charged-current weak interactions that include muon-neutrinos or muons, as well as the role of neutron decay for neutrino transport in CCSNe. All of these reactions were previously neglected in CCSN-simulations. We derive and compute the matrix element and subsequent semi-analytic expressions for transport properties like the inverse mean free path of the new reactions. It is found that these reactions are important for muon neutrinos and low energy electron antineutrinos at very high densities in the protoneutron star surface. Consequently their implementation might lead to several changes in the prediction of CCSNe signatures such as the nucleosynthesis yields. Second we improve the precision in the computation of well known neutrino-nucleon reactions like neutrino absorption on neutrons. We derive semi-analytic expressions for transport properties that use less restrictive approximations while keeping the computational demand constant. Therefore we consider the full relativistic kinematics of all participating particles i.e. allowing for relativistic nucleons and finite lepton masses. Also the weak magnetism terms of the matrix elements are explicitly included to all orders. From our results we suggest that the

  6. Pion decay constants in dense skyrmion matter

    Directory of Open Access Journals (Sweden)

    Lee H.-J.

    2010-10-01

    Full Text Available According to the QCD, the hadronic matter can have various phases with matter density and temperature. In general, when there is phase transition in a matter, it is known that a symmetry in the matter changes. In case of the hadronic matter, the chiral symmetry in the matter is expected to be restored when the matter density (or temperature increases. The actual order parameter with respect to the chiral symmetry in the hadronic matter is known as the quark condensate from the QCD, but the pion decay constant, corresponding to the radius of the chiral circle, plays the role of the order parameter in an effective field theoretical approach to the QCD. In this paper, by using the skyrmion model which is an effective theory to the QCD, we construct the skyrmion matter as a model of the hadronic matter (nuclear matter and calculate the pion decay constant in the matter. Because of presence of the matter, the pion decay constant is split into the two components, the temporal component and the spatial component. We discuss the phase transition in the skyrmion matter and behavior of the two components of the decay constant for massless pion with density of the skyrmion matter.

  7. Fermion mass and the pressure of dense matter

    CERN Document Server

    Fraga, Eduardo S; 10.1063/1.2714447

    2008-01-01

    We consider a simple toy model to study the effects of finite fermion masses on the pressure of cold and dense matter, with possible applications in the physics of condensates in the core of neutron stars and color superconductivity.

  8. Experimental Studies of the Transport Parameters of Warm Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Chouffani, Khalid [Idaho State Univ., Pocatello, ID (United States)

    2014-12-01

    There is a need to establish fundamental properties of matter and energy under extreme physical conditions. Although high energy density physics (HEDP) research spans a wide range of plasma conditions, there is one unifying regime that is of particular importance and complexity: that of warm dense matter, the transitional state between solid state condensed matter and energetic plasmas. Most laboratory experimental conditions, including inertial confinement implosion, fall into this regime. Because all aspects of laboratory-created high-energy-density plasmas transition through the warm dense matter regime, understanding the fundamental properties to determine how matter and energy interact in this regime is an important aspect of major research efforts in HEDP. Improved understanding of warm dense matter would have significant and wide-ranging impact on HEDP science, from helping to explain wire initiation studies on the Sandia Z machine to increasing the predictive power of inertial confinement fusion modeling. The central goal or objective of our proposed research is to experimentally determine the electrical resistivity, temperature, density, and average ionization state of a variety of materials in the warm dense matter regime, without the use of theoretical calculations. Since the lack of an accurate energy of state (EOS) model is primarily due to the lack of experimental data, we propose an experimental study of the transport coefficients of warm dense matter.

  9. Neutrinos and Nucleosynthesis in Hot and Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, George [Univ. of California, San Diego, CA (United States)

    2016-01-14

    The Topical Collaboration for Neutrinos and Nucleosynthesis in Hot and Dense matter brought together researchers from a variety of nuclear science specialties and a number of institutions to address nuclear physics and neutrino physics problems associated with dense matter and the origin of the elements. See attached final technical reports for (1) the UCSD award and (2) a copy of the report for the whole TC

  10. Phases of Dense Matter in Supernovae and Neutron Stars

    Institute of Scientific and Technical Information of China (English)

    申虹; 王延楠

    2012-01-01

    We study the properties of dense matter at finite temperature with various proton fractions for use in supernova simulations. The relativistic mean-field theory is used to describe homogeneous nuclear matter, while the Thomas-Fermi approximation is adopted to describe inhomogeneous matter. We also discuss the equation of state of neutron star matter at zero temperature in a wide density range. The equation of state at high densities can be significantly softened by the inclusion of hyperons.

  11. Phases of dense matter with holographic instantons

    CERN Document Server

    Preis, Florian

    2016-01-01

    We discuss nuclear matter and the transition to quark matter in the decompactified limit of the Sakai-Sugimoto model. Nuclear matter is included through instantons on the flavor branes of the model. Our approximation is based on the flat-space solution, but we allow for a dynamical instanton width and deformation and compute the energetically preferred number of instanton layers in the bulk as a function of the baryon chemical potential. We determine the regions in parameter space where the binding energy of nuclear matter is like in QCD, and compute the phase diagram in the plane of temperature and chemical potential.

  12. WDM PONs based on colorless technology

    Science.gov (United States)

    Saliou, Fabienne; Simon, Gael; Chanclou, Philippe; Pizzinat, Anna; Lin, Huafeng; Zhou, Enyu; Xu, Zhiguang

    2015-12-01

    Wavelength Division Multiplexing (WDM) Passive Optical Network (PON) is foreseen to be part of the Next Generation Passive Optical Networks. Business and mobile fronthaul networks already express the need to develop WDM PONs in the access segment. Fixed wavelength transceivers based on Coarse WDM are already available to respond to today's market needs but Dense WDM technologies will be needed and colorless technologies are essential to provide simple and cost-effective WDM PON systems. We propose in this paper to demonstrate the capabilities of a DWDM PON system prototype based on self-seeded RSOAs and designed to transmit CPRI over 60 km of fiber at 2.5 Gbit/s.

  13. Warm dense matter and Thomson scattering at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Faeustlin, Roland Rainer

    2010-05-15

    X-ray free electron lasers are powerful tools to investigate moderately to strongly correlated solid density low temperature plasmas, named warm dense matter. These plasmas are of most interest for astrophysics and laser plasma interaction, particularly inertial confinement fusion. This work utilizes the ultrashort soft x-ray pulse duration and high brilliance of the free electron laser in Hamburg, FLASH, to generate warm dense matter and to study its ultrafast processes. The techniques applied are absorption measurement, emission spectroscopy and Thomson scattering. Radiative hydrodynamics and Thomson scattering simulations are used to investigate the impact of temperature and density gradients in the sample and to fit the experimental data. The measurements result in a comprehensive picture of soft x-ray matter interaction related to warm dense matter and yield insight into ultrafast equilibration and relaxation mechanisms, in particular impact ionization and radiative recombination. (orig.)

  14. Quark matter formation in dense stellar objects

    Indian Academy of Sciences (India)

    S C Phatak

    2001-08-01

    It is expected that at very large densities and/or temperatures a quark-hadron phase transition takes place. Lattice QCD calculations at zero baryon density indicate that the transition occurs at c∼ 150-170 MeV. The transition is likely to be second order or a cross over phenomenon. Although not much is known about the density at which the phase transition takes place at small temperatures, it is expected to occur around the nuclear densities of few times nuclear matter density. Also, there is a strong reason to believe that the quark matter formed after the phase transition is in colour superconducting phase. The matter densities in the interior of neutron stars being larger than the nuclear matter density, the neutron star cores may possibly consist of quark matter which may be formed during the collapse of supernova. Starting with the assumption that the quark matter, when formed consists of predominantly and quarks, we consider the evolution of quarks by weak interactions in the present work. The reaction rates and time required to reach the chemical equilibrium are computed here. Our calculations show that the chemical equilibrium is reached in about 10-7 seconds. Further more during the equilibration process enormous amont of energy is released and copious numbers of neutrinos are produced. Implications of these on the evolution of supernovae will be discussed.

  15. Recent progress on dense nuclear matter in skyrmion approaches

    Science.gov (United States)

    Ma, YongLiang; Rho, Mannque

    2017-03-01

    The Skyrme model provides a novel unified approach to nuclear physics. In this approach, single baryon, baryonic matter and medium-modified hadron properties are treated on the same footing. Intrinsic density dependence (IDD) reflecting the change of vacuum by compressed baryonic matter figures naturally in the approach. In this article, we review the recent progress on accessing dense nuclear matter by putting baryons treated as solitons, namely, skyrmions, on crystal lattice with accents on the implications in compact stars.

  16. A multi-wavelength streak-optical-pyrometer for warm-dense matter experiments at NDCX-I and NDCX-II

    Science.gov (United States)

    Ni, P. A.; Bieniosek, F. M.; Henestroza, E.; Lidia, S. M.

    2014-01-01

    We report on a multi-wavelength streak-optical-pyrometer (SOP) developed the for warm-dense-matter (WDM) experiments at the existing NDCX-I facility and the NDCX-II facility currently being commissioned at LBNL. The SOP served as the primary temperature diagnostic in the recent NDCX-I experiments, in which an intense K+ beam was used to heat different metal samples into WDM states. The SOP consists of a spectral grating (visible and near-infrared spectral range) and a fast, high-dynamic-range optical streak camera. The instrument is calibrated absolutely with a NIST-traceable tungsten ribbon lamp and can itself be considered as an absolutely calibrated, time-resolving spectrometer. The sample temperature is determined from fitting the recorded thermal spectrum into the Planck formula multiplied by a model of emissivity.

  17. A multi-wavelength streak-optical-pyrometer for warm-dense matter experiments at NDCX-I and NDCX-II

    Energy Technology Data Exchange (ETDEWEB)

    Ni, P.A., E-mail: pani@lbl.gov; Bieniosek, F.M.; Henestroza, E.; Lidia, S.M.

    2014-01-01

    We report on a multi-wavelength streak-optical-pyrometer (SOP) developed the for warm-dense-matter (WDM) experiments at the existing NDCX-I facility and the NDCX-II facility currently being commissioned at LBNL. The SOP served as the primary temperature diagnostic in the recent NDCX-I experiments, in which an intense K{sup +} beam was used to heat different metal samples into WDM states. The SOP consists of a spectral grating (visible and near-infrared spectral range) and a fast, high-dynamic-range optical streak camera. The instrument is calibrated absolutely with a NIST-traceable tungsten ribbon lamp and can itself be considered as an absolutely calibrated, time-resolving spectrometer. The sample temperature is determined from fitting the recorded thermal spectrum into the Planck formula multiplied by a model of emissivity.

  18. Pycnonuclear reactions in dense stellar matter

    CERN Document Server

    Yakovlev, D G; Gnedin, O Y

    2005-01-01

    We discuss pycnonuclear burning of highly exotic atomic nuclei in deep crusts of neutron stars, at densities up to 1e13 g/cc. As an application, we consider pycnonuclear burning of matter accreted on a neutron star in a soft X-ray transient (SXT, a compact binary containing a neutron star and a low-mass companion). The energy released in this burning, while the matter sinks into the stellar crust under the weight of newly accreted material, is sufficient to warm up the star and initiate neutrino emission in its core. The surface thermal radiation of the star in quiescent states becomes dependent of poorly known equation of state (EOS) of supranuclear matter in the stellar core, which gives a method to explore this EOS. Four qualitatively different model EOSs are tested against observations of SXTs. They imply different levels of the enhancement of neutrino emission in massive neutron stars by (1) the direct Urca process in nucleon/hyperon matter; (2) pion condensates; (3) kaon condensates; (4) Cooper pairing ...

  19. Plasmon resonance in warm dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Thiele, R; Bornath, T; Fortmann, C; Holl, A; Redmer, R; Reinholz, H; Ropke, G; Wierling, A; Glenzer, S H; Gregori, G

    2008-02-21

    Collective Thomson scattering with extreme ultraviolet light or x-rays is shown to allow for a robust measurement of the free electron density in dense plasmas. Collective excitations like plasmons appear as maxima in the scattering signal. Their frequency position can directly be related to the free electron density. The range of applicability of the standard Gross-Bohm dispersion relation and of an improved dispersion relation in comparison to calculations based on the dielectric function in random phase approximation is investigated. More important, this well-established treatment of Thomson scattering on free electrons is generalized in the Born-Mermin approximation by including collisions. We show that, in the transition region from collective to non-collective scattering, the consideration of collisions is important.

  20. Dense hadronic matter in neutron stars

    CERN Document Server

    Pagliara, Giuseppe; Lavagno, Andrea; Pigato, Daniele

    2014-01-01

    The existence of stars with masses up to $2 M_{\\odot}$ and the hints of the existence of stars with radii smaller than $\\sim 11$ km seem to require, at the same time, a stiff and a soft hadronic equation of state at large densities. We argue that these two apparently contradicting constraints are actually an indication of the existence of two families of compact stars: hadronic stars which could be very compact and quark stars which could be very massive. In this respect, a crucial role is played, in the hadronic equation of state, by the delta isobars whose early appearance shifts to large densities the formation of hyperons. We also discuss how recent experimental information on the symmetry energy of nuclear matter at saturation indicate, indirectly, an early appearance of delta isobars in neutron star matter.

  1. Collaborative Research: Neutrinos & Nucleosynthesis in Hot Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Sanjay

    2013-09-06

    It is now firmly established that neutrinos, which are copiously produced in the hot and dense core of the supernova, play a role in the supernova explosion mechanism and in the synthesis of heavy elements through a phenomena known as r-process nucleosynthesis. They are also detectable in terrestrial neutrino experiments, and serve as a probe of the extreme environment and complex dynamics encountered in the supernova. The major goal of the UW research activity relevant to this project was to calculate the neutrino interaction rates in hot and dense matter of relevance to core collapse supernova. These serve as key input physics in large scale computer simulations of the supernova dynamics and nucleosynthesis being pursued at national laboratories here in the United States and by other groups in Europe and Japan. Our calculations show that neutrino production and scattering rate are altered by the nuclear interactions and that these modifications have important implications for nucleosynthesis and terrestrial neutrino detection. The calculation of neutrino rates in dense matter are difficult because nucleons in the dense matter are strongly coupled. A neutrino interacts with several nucleons and the quantum interference between scattering off different nucleons depends on the nature of correlations between them in dense matter. To describe these correlations we used analytic methods based on mean field theory and hydrodynamics, and computational methods such as Quantum Monte Carlo. We found that due to nuclear effects neutrino production rates at relevant temperatures are enhanced, and that electron neutrinos are more easily absorbed than anti-electron neutrinos in dense matter. The latter, was shown to favor synthesis of heavy neutron-rich elements in the supernova.

  2. Dense Matter and Neutron Stars in Parity Doublet Models

    CERN Document Server

    Schramm, S; Negreiros, R; Steinheimer, J

    2011-01-01

    We investigate the properties of dense matter and neutron stars. In particular we discuss model calculations based on the parity doublet picture of hadronic chiral symmetry. In this ansatz the onset of chiral symmetry restoration is reflected by the degeneracy of baryons and their parity partners. In this approach we also incorporate quarks as degrees of freedom to be able to study hybrid stars.

  3. Demonstration of space-resolved x-ray Thomson scattering capability for warm dense matter experiments on the Z accelerator

    Science.gov (United States)

    Ao, T.; Harding, E. C.; Bailey, J. E.; Lemke, R. W.; Desjarlais, M. P.; Hansen, S. B.; Smith, I. C.; Geissel, M.; Maurer, A.; Reneker, J.; Romero, D.; Sinars, D. B.; Rochau, G. A.; Benage, J. F.

    2016-03-01

    Experiments on the Sandia Z pulsed-power accelerator have demonstrated the ability to produce warm dense matter (WDM) states with unprecedented uniformity, duration, and size, which are ideal for investigations of fundamental WDM properties. For the first time, space-resolved x-ray Thomson scattering (XRTS) spectra from shocked carbon foams were recorded on Z. The large (>20 MA) electrical current produced by Z was used to launch Al flyer plates up to 25 km/s. The impact of the flyer plate on a CH2 foam target produced a shocked state with an estimated pressure of 0.75 Mbar, density of 0.52 g/cm3, and temperature of 4.3 eV. Both unshocked and shocked portions of the foam target were probed with 6.2 keV x-rays produced by focusing the Z-Beamlet laser onto a nearby Mn foil. The data are composed of three spatially distinct spectra that were simultaneously captured with a single spectrometer with high spectral (4.8 eV) and spatial (190 μm) resolutions. Detailed spectral information from three target locations is provided simultaneously: the incident x-ray source, the scattered signal from unshocked foam, and the scattered signal from shocked foam.

  4. Modeling warm dense matter experiments using the 3D ALE-AMR code and the move toward exascale computing

    Directory of Open Access Journals (Sweden)

    Koniges Alice

    2013-11-01

    Full Text Available The Neutralized Drift Compression Experiment II (NDCX II is an induction accelerator planned for initial commissioning in 2012. The final design calls for a 3 MeV, Li+ ion beam, delivered in a bunch with characteristic pulse duration of 1 ns, and transverse dimension of order 1 mm. The NDCX II will be used in studies of material in the warm dense matter (WDM regime, and ion beam/hydrodynamic coupling experiments relevant to heavy ion based inertial fusion energy. We discuss recent efforts to adapt the 3D ALE-AMR code to model WDM experiments on NDCX II. The code, which combines Arbitrary Lagrangian Eulerian (ALE hydrodynamics with Adaptive Mesh Refinement (AMR, has physics models that include ion deposition, radiation hydrodynamics, thermal diffusion, anisotropic material strength with material time history, and advanced models for fragmentation. Experiments at NDCX-II will explore the process of bubble and droplet formation (two-phase expansion of superheated metal solids using ion beams. Experiments at higher temperatures will explore equation of state and heavy ion fusion beam-to-target energy coupling efficiency. Ion beams allow precise control of local beam energy deposition providing uniform volumetric heating on a timescale shorter than that of hydrodynamic expansion. We also briefly discuss the effects of the move to exascale computing and related computational changes on general modeling codes in fusion.

  5. Development and testing of a pulsed helium ion source for probing materials and warm dense matter studies

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Q., E-mail: qji@lbl.gov; Seidl, P. A.; Waldron, W. L.; Takakuwa, J. H.; Persaud, A.; Schenkel, T. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Friedman, A.; Grote, D. P.; Barnard, J. J. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2016-02-15

    The neutralized drift compression experiment was designed and commissioned as a pulsed, linear induction accelerator to drive thin targets to warm dense matter (WDM) states with peak temperatures of ∼1 eV using intense, short pulses (∼1 ns) of 1.2 MeV lithium ions. At that kinetic energy, heating a thin target foil near the Bragg peak energy using He{sup +} ions leads to more uniform energy deposition of the target material than Li{sup +} ions. Experiments show that a higher current density of helium ions can be delivered from a plasma source compared to Li{sup +} ions from a hot plate type ion source. He{sup +} beam pulses as high as 200 mA at the peak and 4 μs long were measured from a multi-aperture 7-cm-diameter emission area. Within ±5% variation, the uniform beam area is approximately 6 cm across. The accelerated and compressed pulsed ion beams can be used for materials studies and isochoric heating of target materials for high energy density physics experiments and WDM studies.

  6. Thermal density functional theory, ensemble density functional theory, and potential functional theory for warm dense matter

    Science.gov (United States)

    Pribram-Jones, Aurora

    Warm dense matter (WDM) is a high energy phase between solids and plasmas, with characteristics of both. It is present in the centers of giant planets, within the earth's core, and on the path to ignition of inertial confinement fusion. The high temperatures and pressures of warm dense matter lead to complications in its simulation, as both classical and quantum effects must be included. One of the most successful simulation methods is density functional theory-molecular dynamics (DFT-MD). Despite great success in a diverse array of applications, DFT-MD remains computationally expensive and it neglects the explicit temperature dependence of electron-electron interactions known to exist within exact DFT. Finite-temperature density functional theory (FT DFT) is an extension of the wildly successful ground-state DFT formalism via thermal ensembles, broadening its quantum mechanical treatment of electrons to include systems at non-zero temperatures. Exact mathematical conditions have been used to predict the behavior of approximations in limiting conditions and to connect FT DFT to the ground-state theory. An introduction to FT DFT is given within the context of ensemble DFT and the larger field of DFT is discussed for context. Ensemble DFT is used to describe ensembles of ground-state and excited systems. Exact conditions in ensemble DFT and the performance of approximations depend on ensemble weights. Using an inversion method, exact Kohn-Sham ensemble potentials are found and compared to approximations. The symmetry eigenstate Hartree-exchange approximation is in good agreement with exact calculations because of its inclusion of an ensemble derivative discontinuity. Since ensemble weights in FT DFT are temperature-dependent Fermi weights, this insight may help develop approximations well-suited to both ground-state and FT DFT. A novel, highly efficient approach to free energy calculations, finite-temperature potential functional theory, is derived, which has the

  7. Nucleation of strange matter in dense stellar cores

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, J.E. (Instituto Astronomico e Geofisico, Universidade de Sao Paulo, Avenida M. Stefano 4200, Agua Funda (04301) Sao Paulo, Sao Paulo (Brazil)); Benvenuto, O.G. (Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N (1900) La Plata (Argentina)); Vucetich, H. (Departamento de Fisica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 49 y 115, C.C.67 (1900) La Plata (Argentina))

    1992-05-15

    We investigate the nucleation of strange quark matter inside hot, dense nuclear matter. Applying Zel'dovich's kinetic theory of nucleation we find a lower limit of the temperature {ital T} for strange-matter bubbles to appear, which happens to be satisfied inside the Kelvin-Helmholtz cooling era of a compact star life but not much after it. Our bounds thus suggest that a prompt conversion could be achieved, giving support to earlier expectations for nonstandard type-II supernova scenarios.

  8. Self-consistent proton crystallization in dense neutron star matter

    Energy Technology Data Exchange (ETDEWEB)

    Kutschera, M. [Institute of Nuclear Physics, Cracow (Poland); Wojcik, W. [Politechnika Krakowska, Cracow (Poland)

    1992-11-01

    We construct a solid-like variational wave functions for protons localized in dense neutron star matter. The localized protons are centered on the lattice sites and the neutron background is described by periodic Bloch wave functions. The self-consistent periodic structure arises due to a collective mean field. For low proton fraction the periodic potential is weak and the neutron Fermi surface is well approximated by a sphere. With the Skyrme forces we find that the proton solid is of lower energy than a uniform matter for densities above n{sub l} {approx} 4 n{sub 0}, where n{sub 0} = 0.17 fm{sup -3} is the nuclear saturation density. We discuss implications of the proton crystallization for properties of dense matter in neutron stars. (author). 7 refs, 8 figs.

  9. Modeling the jet quenching in hot and dense QCD matter

    CERN Document Server

    Lokhtin, I P; Petrushanko, S V; Snigirev, A M; Arsene, I; Tywoniuk, K

    2009-01-01

    One of the important perturbative ("hard") probes of hot and dense QCD matter is the medium-induced energy loss of energetic partons, so called "jet quenching", which is predicted to be very different in cold nuclear matter and in QGP, and leads to a number of phenomena which are already seen in the RHIC data on the qualitative level. The inclusion of jet quenching and other important collective effects, such as radial and elliptic flows, in the existing Monte-Carlo models of relativistic heavy ion collisions is discussed. Some issues on the corresponding physical observables at RHIC and LHC energies obtained with HYDJET++ model are presented.

  10. Topical Collaboration "Neutrinos and Nucleosynthesis in Hot and Dense Matter"

    Energy Technology Data Exchange (ETDEWEB)

    Allahverdi, Rouzbeh [Univ. of New Mexico, Albuquerque, NM (United States)

    2015-09-18

    This is the final technical report describing contributions from the University of New Mexico to Topical Collaboration on "Neutrinos and Nucleosynthesis in Hot and Dense Matter" in the period June 2010 through May 2015. During the funding period, the University of New Mexico successfully hired Huaiyu Duan as a new faculty member with the support from DOE, who has contributed to the Topical Collaboration through his research and collaborations.

  11. The EOS and neutrino interactions in dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, M.; Reddy, S. [Dept. of Physics and Astronomy, SUNY at Stony Brook, Stony Brook, NY (United States)

    1998-06-01

    The deleptonization and cooling times of a newly born neutron star depend on the equation of state (EOS) and neutrino opacities in dense matter. Through model calculations we show that effects of Pauli blocking and many-body correlations due to strong interactions reduce both the neutral and charged current neutrino cross sections by large factors compared to the case in which these effects are ignored. (orig.)

  12. Stability of superfluid vortices in dense quark matter

    CERN Document Server

    Alford, Mark G; Vachaspati, Tanmay; Windisch, Andreas

    2016-01-01

    Superfluid vortices in the color-flavor-locked (CFL) phase of dense quark matter are known to be energetically disfavored relative to well-separated triplets of "semi-superfluid" color flux tubes. However, the short-range interaction (metastable versus unstable) has not been established. In this paper we perform numerical calculations using the effective theory of the condensate field, mapping the regions in the parameter space of coupling constants where the vortices are metastable versus unstable. For the case of zero gauge coupling we analytically identify a candidate for the unstable mode, and show that it agrees well with the results of the numerical calculations. We find that in the region of the parameter space that seems likely to correspond to real-world CFL quark matter the vortices are unstable, indicating that if such matter exists in neutron star cores it is very likely to contain semi-superfluid color flux tubes rather than superfluid vortices.

  13. Dense stellar matter with trapped neutrinos under strong magnetic fields

    CERN Document Server

    Rabhi, A

    2009-01-01

    We investigate the effects of strong magnetic fields on the equation of state of dense stellar neutrino-free and neutrino-trapped matter. Relativistic nuclear models both with constant couplings (NLW) and with density dependent parameters (DDRH) and including hyperons are considered . It is shown that at low densities neutrinos are suppressed in the presence of the magnetic field. The magnetic field reduces the strangeness fraction of neutrino-free matter and increases the strangeness fraction of neutrino-trapped matter. The mass-radius relation of stars described by these equations of state are determined. The magnetic field makes the overall equation of state stiffer and the stronger the field the larger the mass of maximum mass star and the smaller the baryon density at the center of the star. As a consequence in the presence of strong magnetic fields the possibility that a protoneutron star evolves to a blackhole is smaller.

  14. Electron-ion and ion-ion potentials for modeling warm dense matter: Applications to laser-heated or shock-compressed Al and Si.

    Science.gov (United States)

    Dharma-wardana, M W C

    2012-09-01

    The pair interactions Uij(r) determine the thermodynamics and linear transport properties of matter via the pair-distribution functions (PDFs), i.e., gij(r). Great simplicity is achieved if Uij(r) could be directly used to predict material properties via classical simulations, avoiding many-body wave functions. Warm dense matter (WDM) is encountered in quasiequilibria where the electron temperature Te differs from the ion temperature Ti, as in laser-heated or in shock-compressed matter. The electron PDFs gee(r) as perturbed by the ions are used to evaluate fully nonlocal exchange-correlation corrections to the free energy, using hydrogen as an example. Electron-ion potentials for ions with a bound core are discussed with Al and Si as examples, for WDM with Te≠Ti, and valid for times shorter than the electron-ion relaxation time. In some cases the potentials develop attractive regions and then become repulsive and "Yukawa-like" for higher Te. These results clarify the origin of initial phonon hardening and rapid release. Pair potentials for shock-heated WDM show that phonon hardening would not occur in most such systems. Defining meaningful quasiequilibrium static transport coefficients consistent with the dynamic values is addressed. There seems to be no meaningful "static conductivity" obtainable by extrapolating experimental or theoretical σ(ω,Ti,Te) to ω→0, unless Ti→Te as well. Illustrative calculations of quasistatic resistivities R(Ti,Te) of laser-heated as well as shock-heated aluminum and silicon are presented using our pseudopotentials, pair potentials, and classical integral equations. The quasistatic resistivities display clear differences in their temperature evolutions, but are not the strict ω→0 limits of the dynamic values.

  15. Neutron Star Dense Matter Equation of State Constraints with NICER

    Science.gov (United States)

    Bogdanov, Slavko; Arzoumanian, Zaven; Chakrabarty, Deepto; Guillot, Sebastien; Kust Harding, Alice; Ho, Wynn C. G.; Lamb, Frederick K.; Mahmoodifar, Simin; Miller, M. Coleman; Morsink, Sharon; Ozel, Feryal; Psaltis, Dimitrios; Ray, Paul S.; Riley, Tom; Strohmayer, Tod E.; Watts, Anna; Wolff, Michael Thomas; Gendreau, Keith

    2017-08-01

    One of the principal goals of the Neutron Star Interior Composition Explorer (NICER) is to place constraints on the dense matter equation of state through sensitive X-ray observations of neutron stars. The NICER mission will focus on measuring the masses and radii of several relatively bright, thermally-emitting, rotation-powered millisecond pulsars, by fitting models that incorporate all relevant relativistic effects and atmospheric radiation transfer processes to their periodic soft X-ray modulations. Here, we provide an overview of the targets NICER will observe and tthe technique and models that have been developed by the NICER team to estimate the masses and radii of these pulsars.

  16. Cold and Dense Matter in a Magnetic Field

    CERN Document Server

    de la Incera, Vivian

    2009-01-01

    Our Universe is full of regions where extreme physical conditions are realized. Among the most intriguing cases are the so-called magnetars: neutron stars with very dense cores and super-strong magnetic fields. In this paper I review the current understanding of the physical properties of quark matter at ultra-high density in the presence of very large magnetic fields. I will discuss the main results on this topic, the main challenges that still remain, and how they could be related to the physics of magnetars.

  17. Thermal Effects in Dense Matter Beyond Mean Field Theory

    CERN Document Server

    Constantinou, Constantinos; Prakash, Madappa

    2016-01-01

    The formalism of next-to-leading order Fermi Liquid Theory is employed to calculate the thermal properties of symmetric nuclear and pure neutron matter in a relativistic many-body theory beyond the mean field level which includes two-loop effects. For all thermal variables, the semi-analytical next-to-leading order corrections reproduce results of the exact numerical calculations for entropies per baryon up to 2. This corresponds to excellent agreement down to sub-nuclear densities for temperatures up to $20$ MeV. In addition to providing physical insights, a rapid evaluation of the equation of state in the homogeneous phase of hot and dense matter is achieved through the use of the zero-temperature Landau effective mass function and its derivatives.

  18. Hot dense magnetized ultrarelativistic spinor matter in a slab

    CERN Document Server

    Sitenko, Yu A

    2016-01-01

    Properties of hot dense ultrarelativistic spinor matter in a slab of finite width, placed in a transverse uniform magnetic field, are studied. The admissible set of boundary conditions is determined by the requirement that spinor matter be confined inside the slab. In thermal equilibrium, the chiral separation effect in the slab is shown to depend both on temperature and chemical potential; this is distinct from the unrealistic case of the magnetic field filling the unbounded (infinite) medium, when the effect is temperature-independent. In the realistic case of the slab, a stepwise behaviour of the axial current density at zero temperature is smoothed out as temperature increases, turning into a linear behaviour at infinitely large temperature. A choice of boundary conditions can facilitate either augmentation or attenuation of the chiral separation effect; in particular, the effect can persist even at zero chemical potential, if temperature is nonzero. Thus the boundary condition can serve as a source that ...

  19. Thermal conductivity measurements of proton-heated warm dense matter

    Science.gov (United States)

    McKelvey, A.; Fernandez-Panella, A.; Hua, R.; Kim, J.; King, J.; Sio, H.; McGuffey, C.; Kemp, G. E.; Freeman, R. R.; Beg, F. N.; Shepherd, R.; Ping, Y.

    2015-06-01

    Accurate knowledge of conductivity characteristics in the strongly coupled plasma regime is extremely important for ICF processes such as the onset of hydrodynamic instabilities, thermonuclear burn propagation waves, shell mixing, and efficient x-ray conversion of indirect drive schemes. Recently, an experiment was performed on the Titan laser platform at the Jupiter Laser Facility to measure the thermal conductivity of proton-heated warm dense matter. In the experiment, proton beams generated via target normal sheath acceleration were used to heat bi-layer targets with high-Z front layers and lower-Z back layers. The stopping power of a material is approximately proportional to Z2 so a sharp temperature gradient is established between the two materials. The subsequent thermal conduction from the higher-Z material to the lower-Z was measured with time resolved streaked optical pyrometry (SOP) and Fourier domain interferometry (FDI) of the rear surface. Results will be used to compare predictions from the thermal conduction equation and the Wiedemann-Franz Law in the warm dense matter regime. Data from the time resolved diagnostics for Au/Al and Au/C Targets of 20-200 nm thickness will be presented.

  20. Hot and dense matter beyond relativistic mean field theory

    CERN Document Server

    Zhang, Xilin

    2016-01-01

    Properties of hot and dense matter are calculated in the framework of quantum hadro-dynamics by including contributions from two-loop (TL) diagrams arising from the exchange of iso-scalar and iso-vector mesons between nucleons. Our extension of mean-field theory (MFT) employs the same five density-independent coupling strengths which are calibrated using the empirical properties at the equilibrium density of iso-spin symmetric matter. Results of calculations from the MFT and TL approximations are compared for conditions of density, temperature, and proton fraction encountered in astrophysics applications involving compact objects. The TL results for the equation of state (EOS) of cold pure neutron matter at sub- and near-nuclear densities agree well with those of modern quantum Monte Carlo and effective field-theoretical approaches. Although the high-density EOS in the TL approximation for neutron-star matter is substantially softer than its MFT counterpart, it is able to support a $2M_\\odot$ neutron star req...

  1. Effective Field Theories for Hot and Dense Matter

    Directory of Open Access Journals (Sweden)

    Blaschke D.

    2010-10-01

    Full Text Available The lecture is divided in two parts. The first one deals with an introduction to the physics of hot, dense many-particle systems in quantum field theory [1, 2]. The basics of the path integral approach to the partition function are explained for the example of chiral quark models. The QCD phase diagram is discussed in the meanfield approximation while QCD bound states in the medium are treated in the rainbow-ladder approximation (Gaussian fluctuations. Special emphasis is devoted to the discussion of the Mott effect, i.e. the transition of bound states to unbound, but resonant scattering states in the continnum under the influence of compression and heating of the system. Three examples are given: (1 the QCD model phase diagram with chiral symmetry ¨ restoration and color superconductivity [3], (2 the Schrodinger equation for heavy-quarkonia [4], and (2 Pions [5] as well as Kaons and D-mesons in the finite-temperature Bethe-Salpeter equation [6]. We discuss recent applications of this quantum field theoretical approach to hot and dense quark matter for a description of anomalous J/ψ supression in heavy-ion collisions [7] and for the structure and cooling of compact stars with quark matter interiors [8]. The second part provides a detailed introduction to the Polyakov-loop Nambu–Jona-Lasinio model [9] for thermodynamics and mesonic correlations [10] in the phase diagram of quark matter. Important relationships of low-energy QCD like the Gell-Mann–Oakes–Renner relation are generalized to finite temperatures. The effect of including the coupling to the Polyakov-loop potential on the phase diagram and mesonic correlations is discussed. An outlook is given to effects of nonlocality of the interactions [11] and of mesonic correlations in the medium [12] which go beyond the meanfield description.

  2. Baryon formation and dissociation in dense hadronic and quark matter

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jincheng [Interdisciplinary Center for Theoretical Study and Department of Modern Physics, University of Science and Technology of China, Anhui 230026 (China); Institute for Theoretical Physics, Johann Wolfgang Goethe University, Max-von-Laue-Str. 1, D-60438 Frankfurt am Main (Germany); Wang Qun, E-mail: qunwang@ustc.edu.cn [Interdisciplinary Center for Theoretical Study and Department of Modern Physics, University of Science and Technology of China, Anhui 230026 (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences, Beijing 100049 (China); Rischke, Dirk H. [Institute for Theoretical Physics, Johann Wolfgang Goethe University, Max-von-Laue-Str. 1, D-60438 Frankfurt am Main (Germany); Frankfurt Institute for Advanced Studies, Ruth-Moufang-Str. 1, D-60438 Frankfurt am Main (Germany)

    2011-10-19

    We study the formation of baryons as composed of quarks and diquarks in hot and dense hadronic matter in a Nambu-Jona-Lasinio (NJL)-type model. We first solve the Dyson-Schwinger equation for the diquark propagator and then use this to solve the Dyson-Schwinger equation for the baryon propagator. We find that stable baryon resonances exist only in the phase of broken chiral symmetry. In the chirally symmetric phase, we do not find a pole in the baryon propagator. In the color-superconducting phase, there is a pole, but it has a large decay width. The diquark does not need to be stable in order to form a stable baryon, a feature typical for so-called Borromean states. Varying the strength of the diquark coupling constant, we also find similarities to the properties of an Efimov state.

  3. Estimating transport coefficients in hot and dense quark matter

    CERN Document Server

    Deb, Paramita; Mishra, Hiranmaya

    2016-01-01

    We compute the transport coefficients-- namely, coefficients of shear and bulk viscosity as well as thermal conductivity for hot and dense quark matter. The calculations are performed within the Nambu Jona Lasinio (NJL) model. The estimation of the transport coefficients is made using a quasi particle approach of solving Boltzmann kinetic equation within the relaxation time approximation. The transition rates are calculated in a manifestly covariant manner to estimate the thermal averaged cross sections for quark quark as well as quark anti-quark scattering. The calculations are performed for finite chemical potential also. Within the parameters of the model, the ratio of shear viscosity to entropy density has a minimum at the Mott transition temperature. At vanishing chemical potential, the ratio of bulk viscosity to entropy density, on the other hand, decrease with temperature with a sharp decrease near the critical temperature and vanishes beyond it. At finite chemical potential, however, it increases slow...

  4. Kinetic theory molecular dynamics and hot dense matter: theoretical foundations.

    Science.gov (United States)

    Graziani, F R; Bauer, J D; Murillo, M S

    2014-09-01

    Electrons are weakly coupled in hot, dense matter that is created in high-energy-density experiments. They are also mildly quantum mechanical and the ions associated with them are classical and may be strongly coupled. In addition, the dynamical evolution of plasmas under these hot, dense matter conditions involve a variety of transport and energy exchange processes. Quantum kinetic theory is an ideal tool for treating the electrons but it is not adequate for treating the ions. Molecular dynamics is perfectly suited to describe the classical, strongly coupled ions but not the electrons. We develop a method that combines a Wigner kinetic treatment of the electrons with classical molecular dynamics for the ions. We refer to this hybrid method as "kinetic theory molecular dynamics," or KTMD. The purpose of this paper is to derive KTMD from first principles and place it on a firm theoretical foundation. The framework that KTMD provides for simulating plasmas in the hot, dense regime is particularly useful since current computational methods are generally limited by their inability to treat the dynamical quantum evolution of the electronic component. Using the N-body von Neumann equation for the electron-proton plasma, three variations of KTMD are obtained. Each variant is determined by the physical state of the plasma (e.g., collisional versus collisionless). The first variant of KTMD yields a closed set of equations consisting of a mean-field quantum kinetic equation for the electron one-particle distribution function coupled to a classical Liouville equation for the protons. The latter equation includes both proton-proton Coulombic interactions and an effective electron-proton interaction that involves the convolution of the electron density with the electron-proton Coulomb potential. The mean-field approach is then extended to incorporate equilibrium electron-proton correlations through the Singwi-Tosi-Land-Sjolander (STLS) ansatz. This is the second variant of KTMD

  5. Novel diagnostics for warm dense matter: application to shock compressed target; Nouveaux diagnostics pour l'etude de la matiere dense et chaude: application aux cibles comprimees par choc laser

    Energy Technology Data Exchange (ETDEWEB)

    Ravasio, A

    2007-03-15

    In this work, we present 3 novel diagnostics for warm dense plasma (WDM) investigations: hard X-ray radiography, proton radiography and X-ray Thomson scattering. Each of these techniques is applied in shock compression experiments. The main objective consists in accessing a new parameter, in addition to shock and particle velocity, for EOS (Equation of State) measurements. In the first chapter we give a deep description of WDM states as strongly coupled and Fermi degenerate states. Then, we introduce how we have generated a WDM state in our experiment: the shock wave. We, in particular, illustrate its formation in the classical laser-matter interaction regime. In the second chapter the principles of standard probing techniques are presented. We see that energetic probe sources are necessary to investigate high Z dense plasmas. The third chapter is dedicated to X-ray radiography results. We report on a first direct density measurement of a shock compressed high Z target using K{alpha} hard X-ray radiation. These results are of great interests as they allow an in-situ characterization of high Z material, impossible with standard techniques. We show that probing a well known material as Al will allow the comparison between our data and the results from already validated simulations. In the fourth chapter, we present the results obtained from proton radiography on low density carbon foam. The data analysis will require the development of a specific Monte-Carlo code to simulate the proton propagation through the shocked target. The comparison of the simulations with the experimental data show a low dependency on density. The fifth chapter is devoted to X-ray Thomson scattering results. For the first time, we have performed collective x-ray Thomson scattering measurement from a shock compressed target, accessing to electron density and temperature. The obtained results are compared with simulated x-ray scattered spectra. The novel technique is then used in the

  6. Diagnostics for heavy ion beam driven Warm dense matter experiments

    Science.gov (United States)

    Ni, Pavel; Bieniosek, Frank; Lidia, Steve; Seidl, Peter; Waldron, Will

    2009-11-01

    A set of diagnostic has been developed for the WDM experiments at Berkeley. The diagnostics are aimed at the in-situ measurement of temperature, expansion velocity and pressure of a WDM sample.A specially developed two-channel pyrometer probes color temperatures at 750 nm,1000 nm and 1400 nm, with 75 ps temporal resolution. The system has a broad dynamic range with a lower limit ˜2000 K and upper limit ˜100000 K. The pyrometer design is based on custom spectrally selective beam splitters and can be upgraded up to seven channels. Continuous target emission from 450 nm to 850 nm is recorder by a custom spectrometer, consisting of a high dynamic range Hamamatsu streak camera and a holographic grating. The system is calibrated absolutely with a tungsten ribbon lamp (NIST traceable). The various sweeping times of the streak unit allows for temporal resolution varying from 1 ps to 1 us. The spectrometer has a lower sensitivity than the pyrometer and applied in experiments with higher temperatures. Hydrodynamic expansion velocity of a target's free surface is measured by a commercially available all- fiber Doppler shift laser interferometer (VISAR). The installed delay etalon allows for velocity detection with 2 m/s precision and 0.5 ns resolution.

  7. Effective Model Approach to the Dense State of QCD Matter

    CERN Document Server

    Fukushima, Kenji

    2010-01-01

    The first-principle approach to the dense state of QCD matter, i.e. the lattice-QCD simulation at finite baryon density, is not under theoretical control for the moment. The effective model study based on QCD symmetries is a practical alternative. However the model parameters that are fixed by hadronic properties in the vacuum may have unknown dependence on the baryon chemical potential. We propose a new prescription to constrain the effective model parameters by the matching condition with the thermal Statistical Model. In the transitional region where thermal quantities blow up in the Statistical Model, deconfined quarks and gluons should smoothly take over the relevant degrees of freedom from hadrons and resonances. We use the Polyakov-loop coupled Nambu--Jona-Lasinio (PNJL) model as an effective description in the quark side and show how the matching condition is satisfied by a simple ansatz on the Polyakov loop potential. Our results favor a phase diagram with the chiral phase transition located at sligh...

  8. Some Recent Progress on Quark Pairings in Dense Quark and Nuclear Matter

    Institute of Scientific and Technical Information of China (English)

    庞锦毅; 王金成; 王群

    2012-01-01

    In this review article we give a brief overview on some recent progress in quark pairings in dense quark~nuclear matter mostly developed in the past five years. We focus on following aspects in particular: the BCS-BEC crossover in the CSC phase, the baryon formation and dissociation in dense quark/nuclear matter, the Ginzburg-Landau theory for three-flavor dense matter with UA (1) anomaly, and the collective and Nambu-Goldstone modes for the spin-one CSC.

  9. Sound Wave in Hot Dense Matter Created in Heavy Ion Collision

    OpenAIRE

    Sun, X.; Yang, Z.

    2005-01-01

    A model to study the sound wave in hot dense matter created in heavy ion collisions by jet is proposed.The preliminary data of jet shape analysis of PHENIX Collaboration for all centralities and two directions is well explained in this model. Then the wavelength of the sound wave, the natural frequency of the hot dense matter and the speed of sound wave are estimated from the fit.

  10. Decay of Langmuir wave in dense plasmas and warm dense matter

    CERN Document Server

    Son, S; Moon, Sung Joon

    2010-01-01

    The decays of the Langmuir waves in dense plasmas are computed using the dielectric function theory widely used in the solid state physics. Four cases are considered: a classical plasma, a Maxwellian plasma, a degenerate quantum plasma, and a partially degenerate plasma. The result is considerably different from the conventional Landau damping theory.

  11. Fractionized Skyrmions in Dense Compact-Star Matter

    CERN Document Server

    Harada, Masayasu; Lee, Hyun Kyu; Rho, Mannque

    2016-01-01

    The hadronic matter described as a skyrmion matter embedded in an FCC crystal is found to turn into a half-skyrmion matter with vanishing (in the chiral limit) quark condensate and {\\it non-vanishing} pion decay constant {$f_\\pi$} at a density $n_{1/2}$ lower than or near the critical density $n_c$ at which hadronic matter changes over to a chiral symmetry restored phase with possibly deconfined quarks. When hidden local gauge fields and a dilaton scalar of spontaneously broken scale symmetry with decay constant $f_\\chi$ are incorporated, this half-skyrmion phase is characterized by $f_\\chi\\approx f_\\pi\

  12. Semi-analytical calculations for parameters of boiling layer in isetropic expansion of warm dense matter with van der Waals equation of state

    CERN Document Server

    Borovikov, Dmitry

    2012-01-01

    Features and parameters of \\boiling" liquid layer, which arises under conditions of isentropic expansion of warm dense matter (WDM), are stud- ied with the use of simplest van der Waals equation of state (EOS). Advan- tage of this EOS is possibility of demonstrable and semi-analytical descrip- tion of thermo- and hydrodynamics of the process. Idealized self-similar case of behavior of matter on interception of equilibrium (not metastable) isoentropic curve and boundary of gas-liquid coexistence curve (binodal) is analyzed. The possibility of formation of such "liquid layer" was studied previously in [1] during solving the problem of ablation of metal surface under the action of strong laser radiation. Peculiarity of such "freezing" of finite portion of expanding matter in the state, which corresponds to the binodal of gas-liquid or/and other phase transitions|so called "phase freezeout"and prospects of applications of this phenomenon for intended generation of uniform and extensive zone of previously unexplor...

  13. A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics.

    Science.gov (United States)

    Mabey, P; Richardson, S; White, T G; Fletcher, L B; Glenzer, S H; Hartley, N J; Vorberger, J; Gericke, D O; Gregori, G

    2017-01-30

    The state and evolution of planets, brown dwarfs and neutron star crusts is determined by the properties of dense and compressed matter. Due to the inherent difficulties in modelling strongly coupled plasmas, however, current predictions of transport coefficients differ by orders of magnitude. Collective modes are a prominent feature, whose spectra may serve as an important tool to validate theoretical predictions for dense matter. With recent advances in free electron laser technology, X-rays with small enough bandwidth have become available, allowing the investigation of the low-frequency ion modes in dense matter. Here, we present numerical predictions for these ion modes and demonstrate significant changes to their strength and dispersion if dissipative processes are included by Langevin dynamics. Notably, a strong diffusive mode around zero frequency arises, which is not present, or much weaker, in standard simulations. Our results have profound consequences in the interpretation of transport coefficients in dense plasmas.

  14. Astrophysical Constraints on Dense Matter in Neutron Stars

    CERN Document Server

    Miller, M Coleman

    2013-01-01

    Ever since the discovery of neutron stars it has been realized that they serve as probes of a physical regime that cannot be accessed in laboratories: strongly degenerate matter at several times nuclear saturation density. Existing nuclear theories diverge widely in their predictions about such matter. It could be that the matter is primarily nucleons, but it is also possible that exotic species such as hyperons, free quarks, condensates, or strange matter may dominate this regime. Astronomical observations of cold high-density matter are necessarily indirect, which means that we must rely on measurements of quantities such as the masses and radii of neutron stars and their surface effective temperatures as a function of age. Here we review the current status of constraints from various methods and the prospects for future improvements.

  15. Fractionized Skyrmions in Dense Compact-Star Matter

    Science.gov (United States)

    Harada, Masayasu; Ma, Yong-Liang; Lee, Hyun Kyu; Rho, Mannque

    The hadronic matter described as a skyrmion matter embedded in an FCC crystal is found to turn into a half-skyrmion matter with vanishing (in the chiral limit) quark condensate and non-vanishing pion decay constant fπ at a density n1/2 lower than or near the critical density nc at which hadronic matter changes over to a chiral symmetry restored phase with possibly deconfined quarks. When hidden local gauge fields and a dilaton scalar of spontaneously broken scale symmetry with decay constant fχ are incorporated, this half-skyrmion phase is characterized by fχ ≈ fπ ≠ 0 with the hidden gauge coupling g ≠ 0 but ≪ 1. While chiral symmetry is restored globally in this region in the sense that space-averaged, figures as a doorway to chiral restoration. The fractionization of skyrmion matter into half-skyrmion matter has a tantalizing analogy to what appears to happen in condensed matter in (2+1) dimensions where half-skyrmions or "meron" enter as relevant degrees of freedom at the interface.

  16. Phases of dense matter with non-spherical nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Pethick, C.J. [NORDITA, Copenhagen (Denmark)]|[Dept. of Physics, Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States); Ravenhall, D.G. [Dept. of Physics, Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)

    1998-06-01

    A brief review is given of some of the important physics related to phases with non-spherical nuclei that can exist in neutron stars and in matter in stellar collapse at densities just below the saturation density of nuclear matter. Comparisons are made with other systems that exhibit similar liquid-crystal-like phases, both in nuclear physics and in condensed matter physics. A short account is given of recent work on the elastic properties of these phases, and their vibration spectrum, as well as on neutron superfluid gaps. (orig.)

  17. Nucleon effective masses in field theories of dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.H.; Reddy, S.; Prakash, M. [Dept. of Physics and Astronomy, Stony Brook, NY (United States)

    1998-06-01

    We point out some generic trends of effective masses in commonly used field-theoretical descriptions of stellar matter in which several species of strongly interacting particles of dissimilar masses may be present. (orig.)

  18. Many-body forces, isospin asymmetry and dense hyperonic matter

    CERN Document Server

    Gomes, R O; Schramm, S; Vascconcellos, C A Z

    2015-01-01

    The equation of state (EoS) of asymmetric nuclear matter at high densities is a key topic for the description of matter inside neutron stars. The determination of the properties of asymmetric nuclear matter, such as the symmetry energy ($a_{sym}$) and the slope of the symmetry energy ($L_0$) at saturation density, has been exaustively studied in order to better constrain the nuclear matter EoS. However, differently from symmetric matter properties that are reasonably constrained, the symmetry energy and its slope still large uncertainties in their experimental values. Regarding this subject, some studies point towards small values of the slope of the symmetry energy, while others suggest rather higher values. Such a lack of agreement raised a certain debate in the scientific community. In this paper, we aim to analyse the role of these properties on the behavior of asymmetric hyperonic matter. Using the formalism presented in Ref. (R.O. Gomes et al 2014}, which considers many-body forces contributions in the ...

  19. The ab initio equation of state of hydrogen in the warm dense matter and its application to the implosion of targets for the inertial confinement fusion; Equation d'etat ab initio de l'hydrogene dans la matiere dense et tiede et application a l'implosion de cibles pour la fusion par confinement inertiel

    Energy Technology Data Exchange (ETDEWEB)

    Caillabet, L.

    2011-03-25

    In the field of the inertial confinement fusion (ICF), the equation of state (EoS) of the hydrogen and its isotopes is one of the most important properties to know. The EoS based on chemical models have difficulty in giving an unambiguous description of the hydrogen in the strong coupled and partial degenerate regime, called Warm Dense Matter (WDM). Indeed, these models use potential with adjustable parameters to describe the many body interactions which are important in the WDM. On the other hand, the ab initio methods resolve almost exactly the quantum many body problem and are thus particularly relevant in this domain. In the first part of this thesis, we describe how we built a table of a multi-phase EoS of the hydrogen, using ab initio methods in the field of the WDM. We show in particular that this EoS is in very good agreement with most of the available experimental data (principal Hugoniot, sound velocity in the molecular fluid, melting curve at low pressure, measurements of multiple shocks). In the second part, we present a direct application of our EoS by showing its influence on the criteria of ignition and combustion of two target designs for ICF: a self-ignited target which will be used on the Laser MegaJoule (LMJ), and a shock-ignited target. We show in particular that the optimization of the laser pulse allowing maximizing the thermonuclear energy is strongly dependent on the precision of the EoS in the strong coupled and degenerate domain. (author) [French] Dans le domaine de la fusion par confinement inertiel (FCI), l'equation d'etat (EoS) de l'hydrogene et de ses isotopes est tres certainement une des proprietes les plus importantes a connaitre. Les EoS basees sur des modeles chimiques peinent a donner une description univoque de l'hydrogene dans le domaine de couplage et de degenerescence partiels, appele matiere dense et tiede, ou Warm Dense Matter (WDM). En effets, ces modeles utilisent des potentiels ad hoc pour decrire les

  20. Scale-invariant hidden local symmetry, topology change, and dense baryonic matter

    Science.gov (United States)

    Paeng, Won-Gi; Kuo, Thomas T. S.; Lee, Hyun Kyu; Rho, Mannque

    2016-05-01

    When scale symmetry is implemented into hidden local symmetry in low-energy strong interactions to arrive at a scale-invariant hidden local symmetric (HLS) theory, the scalar f0(500 ) may be interpreted as pseudo-Nambu-Goldstone (pNG) boson, i.e., dilaton, of spontaneously broken scale invariance, joining the pseudoscalar pNG bosons π and the matter fields V =(ρ ,ω ) as relevant degrees of freedom. Implementing the skyrmion-half-skyrmion transition predicted at large Nc in QCD at a density roughly twice the nuclear matter density found in the crystal simulation of dense skyrmion matter, we determine the intrinsically density-dependent "bare parameters" of the scale-invariant HLS Lagrangian matched to QCD at a matching scale ΛM. The resulting effective Lagrangian, with the parameters scaling with the density of the system, is applied to nuclear matter and dense baryonic matter relevant to massive compact stars by means of the double-decimation renormalization-group Vlow k formalism. We satisfactorily postdict the properties of normal nuclear matter and more significantly predict the equation of state of dense compact-star matter that quantitatively accounts for the presently available data coming from both the terrestrial and space laboratories. We interpret the resulting structure of compact-star matter as revealing how the combination of hidden-scale symmetry and hidden local symmetry manifests itself in compressed baryonic matter.

  1. Theory of the equation of state of hot dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Barbee, T W; Surh, M; Yang, L H

    1999-07-23

    Ab initio molecular dynamics calculations are adapted to treat dense plasmas for temperatures exceeding the electronic Fermi temperature. Extended electronic states are obtained in a plane wave basis by using pseudopotentials for the ion cores in the local density approximation to density functional theory. The method reduces to conventional first principles molecular dynamics at low temperatures with the expected high level of accuracy. The occurrence of thermally excited ion cores at high temperatures is treated by means of final state pseudopotentials. The method is applied to the shock compression Hugoniot equation of state for aluminum. Good agreement with experiment is found for temperatures ranging from zero through 105K.

  2. Warm and dense stellar matter under strong magnetic fields

    CERN Document Server

    Rabhi, A; Providência, C

    2011-01-01

    We investigate the effects of strong magnetic fields on the equation of state of warm stellar matter as it may occur in a protoneutron star. Both neutrino free and neutrino trapped matter at a fixed entropy per baryon are analyzed. A relativistic mean field nuclear model, including the possibility of hyperon formation, is considered. A density dependent magnetic field with the magnitude $10^{15}$ G at the surface and not more than $3\\times 10^{18}$ G at the center is considered. The magnetic field gives rise to a neutrino suppression, mainly at low densities, in matter with trapped neutrinos. It is shown that an hybrid protoneutron star will not evolve to a low mass blackhole if the magnetic field is strong enough and the magnetic field does not decay. However, the decay of the magnetic field after cooling may give rise to the formation of a low mass blackhole.

  3. Dense baryonic matter: constraints from recent neutron star observations

    CERN Document Server

    Hell, Thomas

    2014-01-01

    Updated constraints from neutron star masses and radii impose stronger restrictions on the equation of state for baryonic matter at high densities and low temperatures. The existence of two-solar-mass neutron stars rules out many soft equations of state with prominent "exotic" compositions. The present work reviews the conditions required for the pressure as a function of baryon density in order to satisfy these new constraints. Several scenarios for sufficiently stiff equations of state are evaluated. The common starting point is a realistic description of both nuclear and neutron matter based on a chiral effective field theory approach to the nuclear many-body problem. Possible forms of hybrid matter featuring a quark core in the center of the star are discussed using a three-flavor Polyakov--Nambu--Jona-Lasinio (PNJL) model. It is found that a conventional equation of state based on nuclear chiral dynamics meets the astrophysical constraints. Hybrid matter generally turns out to be too soft unless addition...

  4. Dense Matter Characterization by X-ray Thomson Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Landen, O L; Glenzer, S H; Edwards, M J; Lee, R W; Collins, G W; Cauble, R C; Hsing, W W; Hammel, B A

    2000-12-29

    We discuss the extension of the powerful technique of Thomson scattering to the x-ray regime for providing an independent measure of plasma parameters for dense plasmas. By spectrally-resolving the scattering, the coherent (Rayleigh) unshifted scattering component can be separated from the incoherent Thomson component, which is both Compton and Doppler shifted. The free electron density and temperature can then be inferred from the spectral shape of the high frequency Thomson scattering component. In addition, as the plasma temperature is decreased, the electron velocity distribution as measured by incoherent Thomson scattering will make a transition from the traditional Gaussian Boltzmann distribution to a density-dependent parabolic Fermi distribution to. We also present a discussion for a proof-of-principle experiment appropriate for a high energy laser facility.

  5. Unified description of dense matter in neutron stars and magnetars

    CERN Document Server

    Chamel, N; Mihailov, L M; Velchev, Ch J; Stoyanov, Zh K; Mutafchieva, Y D; Ivanovich, M D; Fantina, A F; Pearson, J M; Goriely, S

    2013-01-01

    We have recently developed a set of equations of state based on the nuclear energy density functional theory providing a unified description of the different regions constituting the interior of neutron stars and magnetars. The nuclear functionals, which were constructed from generalized Skyrme effective nucleon-nucleon interactions, yield not only an excellent fit to essentially all experimental atomic mass data but were also constrained to reproduce the neutron-matter equation of state as obtained from realistic many-body calculations.

  6. Hyperon-Nucleon Interactions and the Composition of Dense Matter from Quantum Chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Konstantinos Orginos, Silas Beane, Emmanuel Chang, Saul Cohen, Huey-Wen Lin, Tom Luu, Assumpta Parreno, Martin Savage, Andre Walker-Loud, William Detmold

    2012-10-01

    The low-energy n{Sigma}{sup -} interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase-shifts for this system are determined from a numerical evaluation of the QCD path integral using the technique of Lattice QCD. Our results, performed at a pion mass of m{sub {pi}} ~ 389 MeV in two large lattice volumes, and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The calculated interactions indicate that the strange quark plays an important role in dense matter.

  7. Pure quantum states of neutrino with rotating spin in dense magnetized matter

    CERN Document Server

    Arbuzova, E V; Murchikova, E M

    2009-01-01

    The problem of rotation of the neutrino spin in dense matter and in strong electromagnetic field is solved in full agreement with the basic principles of quantum mechanics. We found complete system of wave functions of a massive Dirac neutrino possessing anomalous magnetic moment. These functions are eigenfunctions of kinetic momentum operator and describe neutrino with rotating spin. Using these wave functions it is possible to calculate probabilities of various processes with neutrino in the framework of the Furry picture. The dispersion law for the neutrino in dense magnetized matter is found. It is shown that group velocity of neutrino is independent of spin orientation.

  8. The Modification of the Scalar Field in dense Nuclear Matter

    Directory of Open Access Journals (Sweden)

    Rożynek J.

    2011-04-01

    Full Text Available We show the possible evolution of the nuclear deep inelastic structure function with nuclear density ρ. The nucleon deep inelastic structure function represents distribution of quarks as function of Björken variable x which measures the longitudinal fraction of momentum carried by them during the Deep Inelastic Scattering (DIS of electrons on nuclear targets. Starting with small density and negative pressure in Nuclear Matter (NM we have relatively large inter-nucleon distances and increasing role of nuclear interaction mediated by virtual mesons.When the density approaches the saturation point, ρ = ρ0, we have no longer separate mesons and nucleons but eventually modified nucleon Structure Function (SF in medium. The ratio of nuclear to nucleon SF measured at saturation point is well known as “EMC effect”. For larger density, ρ > ρ0, when the localization of quarks is smaller then 0.3 fm, the nucleons overlap. We argue that nucleon mass should start to decrease in order to satisfy the Momentum Sum Rule (MSR of DIS. These modifications of the nucleon Structure Function (SF are calculated in the frame of the nuclear Relativistic Mean Field (RMF convolution model. The correction to the Fermi energy from term proportional to the pressure is very important and its inclusion modifies the Equation of State (EoS for nuclear matter.

  9. Collective excitations, instabilities, and ground state in dense quark matter

    CERN Document Server

    Gorbar, E V; Miransky, V A; Shovkovy, I A; Hashimoto, Michio

    2006-01-01

    We study the spectrum of light plasmons in the (gapped and gapless) two-flavor color superconducting phases and its connection with the chromomagnetic instabilities and the structure of the ground state. It is revealed that the chromomagnetic instabilities in the 4-7th and 8th gluonic channels correspond to two very different plasmon spectra. These spectra lead us to the unequivocal conclusion about the existence of gluonic condensates (some of which can be spatially inhomogeneous) in the ground state. We also argue that spatially inhomogeneous gluonic condensates should exist in the three-flavor quark matter with the values of the mass of strange quark corresponding to the gapless color-flavor locked state.

  10. Time-evolution of dense hadronic matter in high energy heavy ion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Otuka, Naohiko; Ohnishi, Akira [Hokkaido Univ., Sapporo (Japan). Dept. of Physics; Nara, Yasushi; Maruyama, Tomoyuki; Niita, Koji

    1997-05-01

    Time evolution of hadronic resonance matter in ultrarelativistic nucleus-nucleus collisions are studied in the framework of cascade models. We investigate the role of higher baryonic resonances during the time evolution of hot and dense hadronic matter at AGS energies. Although final hadronic spectrum can reproduced well with and without higher baryonic resonances, the inclusion of higher resonances is shown to prevent the temperature from going beyond 200 MeV. (author)

  11. Highly efficient accelerator of dense matter using laser-induced cavity pressure acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Badziak, J.; Jablonski, S.; Pisarczyk, T.; Raczka, P.; Chodukowski, T.; Kalinowska, Z.; Parys, P.; Rosinski, M.; Borodziuk, S. [Institute of Plasma Physics and Laser Microfusion, 01-497 Warsaw (Poland); Krousky, E. [Institute of Physics, AS CR, 182 21 Prague 8 (Czech Republic); Liska, R.; Kucharik, M. [Czech Technical University, FNSPE, 160 41 Prague 6 (Czech Republic); Ullschmied, J. [Institute of Plasma Physics, AS CR, 182 20 Prague 8 (Czech Republic)

    2012-05-15

    Acceleration of dense matter to high velocities is of high importance for high energy density physics, inertial confinement fusion, or space research. The acceleration schemes employed so far are capable of accelerating dense microprojectiles to velocities approaching 1000 km/s; however, the energetic efficiency of acceleration is low. Here, we propose and demonstrate a highly efficient scheme of acceleration of dense matter in which a projectile placed in a cavity is irradiated by a laser beam introduced into the cavity through a hole and then accelerated in a guiding channel by the pressure of a hot plasma produced in the cavity by the laser beam or by the photon pressure of the ultra-intense laser radiation trapped in the cavity. We show that the acceleration efficiency in this scheme can be much higher than that achieved so far and that sub-relativisitic projectile velocities are feasible in the radiation pressure regime.

  12. Inhomogeneous chiral symmetry breaking in dense neutron-star matter

    Energy Technology Data Exchange (ETDEWEB)

    Buballa, Michael; Carignano, Stefano [Technische Universitaet Darmstadt, Theoriezentrum, Institut fuer Kernphysik, Darmstadt (Germany)

    2016-03-15

    An increasing number of model results suggests that chiral symmetry is broken inhomogeneously in a certain window at intermediate densities in the QCD phase diagram. This could have significant effects on the properties of compact stars, possibly leading to new astrophysical signatures. In this contribution we discuss this idea by reviewing recent results on inhomogeneous chiral symmetry breaking under an astrophysics-oriented perspective. After introducing two commonly studied spatial modulations of the chiral condensate, the chiral density wave and the real kink crystal, we focus on their properties and their effect on the equation of state of quark matter. We also describe how these crystalline phases are affected by different elements which are required for a realistic description of a compact star, such as charge neutrality, the presence of magnetic fields, vector interactions and the interplay with color superconductivity. Finally, we discuss possible signatures of inhomogeneous chiral symmetry breaking in the core of compact stars, considering the cases of mass-radius relations and neutrino emissivity explicitly. (orig.)

  13. Towards the phase diagram of dense two-color matter

    CERN Document Server

    Cotter, Seamus; Hands, Simon; Skullerud, Jon-Ivar

    2012-01-01

    We study two-color QCD with two flavors of Wilson fermion as a function of quark chemical potential mu and temperature T. We find evidence of a superfluid phase at intermediate mu and low T where the quark number density and diquark condensate are both very well described by a Fermi sphere of nearly-free quarks disrupted by a BCS condensate. Our results suggest that the quark contribution to the energy density is negative (and balanced by a positive gauge contribution), although this result is highly sensitive to details of the energy renormalisation. We also find evidence that the chiral condensate in this region vanishes in the massless limit. This region gives way to a region of deconfined quark matter at higher T and mu, with the deconfinement temperature, determined from the renormalised Polyakov loop, decreasing only very slowly with increasing chemical potential. The quark number susceptibility chi_q does not exhibit any qualitative change at the deconfinement transition. We argue that this is because ...

  14. Generation of strong magnetic fields in dense quark matter driven by the electroweak interaction of quarks

    Science.gov (United States)

    Dvornikov, Maxim

    2016-12-01

    We study the generation of strong large scale magnetic fields in dense quark matter. The magnetic field growth is owing to the magnetic field instability driven by the electroweak interaction of quarks. We discuss the situation when the chiral symmetry is unbroken in the degenerate quark matter. In this case we predict the amplification of the seed magnetic field 1012G to the strengths (1014 -1015)G. In our analysis we use the typical parameters of the quark matter in the core of a hybrid star or in a quark star. We also discuss the application of the obtained results to describe the magnetic fields generation in magnetars.

  15. The Neutron Star Mass-Radius Relation and the Equation of State of Dense Matter

    CERN Document Server

    Steiner, Andrew W; Brown, Edward F

    2012-01-01

    The equation of state (EOS) of dense matter has been a long-sought goal of nuclear physics. Equations of state generate unique mass versus radius (M-R) relations for neutron stars, the ultra-dense remnants of stellar evolution. In this work, we determine the neutron star mass-radius relation and, based on recent observations of both transiently accreting and bursting sources, we show that the radius of a 1.4 solar mass neutron star lies between 10.4 and 12.9 km, independent of assumptions about the composition of the core. We show, for the first time, that these constraints remain valid upon removal from our sample of the most extreme transient sources or of the entire set of bursting sources; our constraints also apply even if deconfined quark matter exists in the neutron star core. Our results significantly constrain the dense matter EOS and are, furthermore, consistent with constraints from both heavy-ion collisions and theoretical studies of neutron matter. We predict a relatively weak dependence of the s...

  16. Hyperon-Nucleon Interactions and the Composition of Dense Nuclear Matter from Quantum Chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Beane, S R; Cohen, S D; Detmold, W; Lin, H -W; Luu, T C; Orginos, K; Parreno, A; Savage, M J

    2012-10-01

    The low-energy neutron-{Sigma}{sup -} interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase shifts for this system are obtained from a numerical evaluation of the QCD path integral using the technique of Lattice QCD. Our calculations, performed at a pion mass of m{sub pi} ~ 389 MeV in two large lattice volumes, and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The interactions determined from QCD are consistent with those extracted from hyperon-nucleon experimental data within uncertainties, and strengthen theoretical arguments that the strange quark is a crucial component of dense nuclear matter.

  17. Hyperon-Nucleon Interactions and the Composition of Dense Nuclear Matter from Quantum Chromodynamics

    CERN Document Server

    Beane, S R; Cohen, S D; Detmold, W; Lin, H -W; Luu, T C; Orginos, K; Parreno, A; Savage, M J; Walker-Loud, A

    2012-01-01

    The low-energy neutron-Sigma^- interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase shifts for this system are obtained from a numerical evaluation of the QCD path integral using the technique of Lattice QCD. Our calculations, performed at a pion mass of m_pi ~ 389 MeV in two large lattice volumes, and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The interactions determined from QCD are consistent with those extracted from hyperon-nucleon experimental data within uncertainties, and strengthen theoretical arguments that the strange quark is a crucial component of dense nuclear matter.

  18. The Korringa-Kohn-Rostoker Method Applied to Warm Dense Matter

    Science.gov (United States)

    Finkenstadt, Daniel; Newnam, Charles E.; Wilson, Brian G.

    2012-02-01

    The electronic structure, EOS and transport properties of warm electrons in an amorphous or disordered configuration of ions is not well described by either solid-state or plasma models. Such warm, dense systems share the characteristic of the solid state that multi-center scattering effects are of paramount importance in forming bands of valence states. Theoretical treatment of the EOS of warm, dense matter therefore requires a way to include significant occupation of higher energy and angular momentum channel continuum states. We are extending the Green's function Kohn-Korringa-Rostoker code MECCA as an all-electron (non-pseudo potential) method that treats arbitrary mixtures of atoms on an ab-initio basis over a broad range of conditions, from cold, solid matter up to hot plasmas at extreme (ICF) compression. Specific examples of Aluminum and Boron-Nitride will be discussed.

  19. ION BEAM HEATED TARGET SIMULATIONS FOR WARM DENSE MATTER PHYSICS AND INERTIAL FUSION ENERGY

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, J.J.; Armijo, J.; Bailey, D.S.; Friedman, A.; Bieniosek, F.M.; Henestroza, E.; Kaganovich, I.; Leung, P.T.; Logan, B.G.; Marinak, M.M.; More, R.M.; Ng, S.F.; Penn, G.E.; Perkins, L.J.; Veitzer, S.; Wurtele, J.S.; Yu, S.S.; Zylstra, A.B.

    2008-08-01

    Hydrodynamic simulations have been carried out using the multi-physics radiation hydrodynamics code HYDRA and the simplified one-dimensional hydrodynamics code DISH. We simulate possible targets for a near-term experiment at LBNL (the Neutralized Drift Compression Experiment, NDCX) and possible later experiments on a proposed facility (NDCX-II) for studies of warm dense matter and inertial fusion energy related beam-target coupling. Simulations of various target materials (including solids and foams) are presented. Experimental configurations include single pulse planar metallic solid and foam foils. Concepts for double-pulsed and ramped-energy pulses on cryogenic targets and foams have been simulated for exploring direct drive beam target coupling, and concepts and simulations for collapsing cylindrical and spherical bubbles to enhance temperature and pressure for warm dense matter studies are described.

  20. Ion Beam Heated Target Simulations for Warm Dense Matter Physics and Inertial Fusion Energy

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, J J; Armijo, J; Bailey, D S; Friedman, A; Bieniosek, F M; Henestroza, E; Kaganovich, I; Leung, P T; Logan, B G; Marinak, M M; More, R M; Ng, S F; Penn, G E; Perkins, L J; Veitzer, S; Wurtele, J S; Yu, S S; Zylstra, A B

    2008-08-12

    Hydrodynamic simulations have been carried out using the multi-physics radiation hydrodynamics code HYDRA and the simplified one-dimensional hydrodynamics code DISH. We simulate possible targets for a near-term experiment at LBNL (the Neutralized Drift Compression Experiment, NDCX) and possible later experiments on a proposed facility (NDCX-II) for studies of warm dense matter and inertial fusion energy related beam-target coupling. Simulations of various target materials (including solids and foams) are presented. Experimental configurations include single pulse planar metallic solid and foam foils. Concepts for double-pulsed and ramped-energy pulses on cryogenic targets and foams have been simulated for exploring direct drive beam target coupling, and concepts and simulations for collapsing cylindrical and spherical bubbles to enhance temperature and pressure for warm dense matter studies are described.

  1. Hyperon-nucleon interactions from quantum chromodynamics and the composition of dense nuclear matter.

    Science.gov (United States)

    Beane, S R; Chang, E; Cohen, S D; Detmold, W; Lin, H-W; Luu, T C; Orginos, K; Parreño, A; Savage, M J; Walker-Loud, A

    2012-10-26

    The low-energy nΣ(-) interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase shifts for this system are obtained from a numerical evaluation of the QCD path integral using the technique of lattice QCD. Our calculations, performed at a pion mass of m(π)~389 MeV in two large lattice volumes and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The interactions determined from lattice QCD are consistent with those extracted from hyperon-nucleon experimental data within uncertainties and strengthen model-dependent theoretical arguments that the strange quark is a crucial component of dense nuclear matter.

  2. Evolution of a dense neutrino gas in matter and electromagnetic field

    CERN Document Server

    Dvornikov, Maxim

    2011-01-01

    We describe the system of massive Weyl fields propagating in background matter and interacting with an external electromagnetic field. The interaction with an electromagnetic field is due to the presence of anomalous magnetic moments. To canonically quantize this system first we develop the classical field theory treatment of Weyl spinors in frames of the Hamilton formalism which accounts for the external fields. Then, on the basis of the exact solution of the wave equation for a massive Weyl field in background matter we obtain the effective Hamiltonian for the description of spin-flavor oscillations of Majorana neutrinos in matter and a magnetic field. Finally, we incorporate in our analysis the neutrino self-interaction which is essential when the neutrino density is sufficiently high. We also discuss the applicability of our results for the studies of collective effects in spin-flavor oscillations of supernova neutrinos in dense matter and strong magnetic field.

  3. Symmetric and anti-symmetric Landau parameters and magnetic properties of dense quark matter

    CERN Document Server

    Pal, Kausik

    2010-01-01

    The dimensionless Fermi liquid parameters (FLPs), $F_{0,1}^{sym}$ and $F_{0,1}^{asym}$, for spin asymmetric dense quark matter have been calculated. In general FLPs are infrared divergent due to the exchange of massless gluons. We use the hard-density-loop (HDL) corrected gluon propagator to remove such divergences. The FLPs so determined are then used to calculate magnetic properties like magnetization $$ and magnetic susceptibility $\\chi_M$ of spin polarized quark matter. We also study the density dependence of $$ and $\\chi_M$.

  4. Spectral Equations-Of-State Theory for Dense, Partially Ionized Matter

    Energy Technology Data Exchange (ETDEWEB)

    Ritchie, A B

    2004-05-14

    The Schroedinger equation is solved in time and space to implement a finite-temperature equation-of-state theory for dense, partially ionized matter. The time-dependent calculation generates a spectrum of quantum states. Eigenfunctions are calculated from a knowledge of the spectrum and used to calculate the electronic pressure and energy. Results are given for LID and compared with results from the INFERNO model.

  5. Dissipationless Hall Current in Dense Quark Matter in a Magnetic Field

    CERN Document Server

    Ferrer, E J

    2016-01-01

    We show the realization of axion electrodynamics within the Dual Chiral Density Wave phase of dense quark matter in the presence of a magnetic field. The system exhibits an anomalous dissipantionless Hall current perpendicular to the magnetic field and an anomalous electric charge density. Connection to topological insulators and 3D optical lattices, as well as possible implications for heavy-ion collisions and neutron stars are outlined.

  6. Relaxation of the chiral imbalance in dense matter of a neutron star

    Directory of Open Access Journals (Sweden)

    Dvornikov Maxim

    2016-01-01

    Full Text Available Using the quantum field theory methods, we calculate the helicity flip of an electron scattering off protons in dense matter of a neutron star. The influence of the electroweak interaction between electrons and background nucleons on the helicity flip is examined. We also derive the kinetic equation for the chiral imbalance. The derived kinetic equation is compared with the results obtained by other authors.

  7. What can we learn from NJL-type models about dense matter?

    CERN Document Server

    Buballa, Michael

    2016-01-01

    The merits and limitations of the Nambu--Jona-Lasinio model as a model for strong interactions at nonzero density are critically discussed. We present several examples, demonstrating that, while in general the results should not be trusted quantitatively, the NJL model is a powerful theoretical tool for getting new insights and ideas about the QCD phase diagram and the dense-matter equation of state.

  8. Hot dense matter creation in short-pulse laser interaction with tamped foils

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S; Pasley, J; Beg, F; Gregori, G; Evans, R G; Notley, M; Mackinnon, A; Glenzer, S; Hansen, S; King, J; Chung, H; Wilks, S; Stephens, R; Freeman, R; Weber, R; Saiz, E G; Khattak, F; Riley, D

    2006-08-15

    The possibility of producing hot dense matter has important applications for the understanding of transport processes in inertial confinement fusion (ICF) [1] and laboratory astrophysics experiments [2]. While the success of ICF requires the correct solution of a complex interaction between laser coupling, equation-of-state, and particle transport problems, the possibility of experimentally recreating conditions found during the ignition phase in a simplified geometry is extremely appealing. In this paper we will show that hot dense plasma conditions found during ICF ignition experiments can be reproduced by illuminating a tamped foil with a high intensity laser. We will show that temperatures on the order of kiloelectronvolts at solid densities can be achieved under controlled conditions during the experiment. Hydrodynamic tamping by surface coatings allows to reach higher density regimes by enabling the diagnosis of matter that has not yet begun to decompress, thus opening the possibility of directly investigating strongly coupled systems [3]. Our experimental diagnostics is based on K-shell spectroscopy coupled to x-ray imaging techniques. Such techniques have recently become prevalent in the diagnosis of hot dense matter [4]. By looking at the presence, and relative strengths, of lines associated with different ionization states, spectroscopy provides considerable insight into plasma conditions. At the same time, curved crystal imaging techniques allow for the spatial resolution of different regions of the target, both allowing for comparison of heating processes with the results of Particle-In-Cell (PIC) and hybrid simulation codes.

  9. Ion potential in warm dense matter: wake effects due to streaming degenerate electrons.

    Science.gov (United States)

    Moldabekov, Zhandos; Ludwig, Patrick; Bonitz, Michael; Ramazanov, Tlekkabul

    2015-02-01

    The effective dynamically screened potential of a classical ion in a stationary flowing quantum plasma at finite temperature is investigated. This is a key quantity for thermodynamics and transport of dense plasmas in the warm-dense-matter regime. This potential has been studied before within hydrodynamic approaches or based on the zero temperature Lindhard dielectric function. Here we extend the kinetic analysis by including the effects of finite temperature and of collisions based on the Mermin dielectric function. The resulting ion potential exhibits an oscillatory structure with attractive minima (wakes) and, thus, strongly deviates from the static Yukawa potential of equilibrium plasmas. This potential is analyzed in detail for high-density plasmas with values of the Brueckner parameter in the range 0.1≤r(s)≤1 for a broad range of plasma temperature and electron streaming velocity. It is shown that wake effects become weaker with increasing temperature of the electrons. Finally, we obtain the minimal electron streaming velocity for which attraction between ions occurs. This velocity turns out to be less than the electron Fermi velocity. Our results allow for reliable predictions of the strength of wake effects in nonequilibrium quantum plasmas with fast streaming electrons showing that these effects are crucial for transport under warm-dense-matter conditions, in particular for laser-matter interaction, electron-ion temperature equilibration, and stopping power.

  10. Warm dense mater: another application for pulsed power hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Reinovsky, Robert Emil [Los Alamos National Laboratory

    2009-01-01

    Pulsed Power Hydrodynamics (PPH) is an application of low-impedance pulsed power, and high magnetic field technology to the study of advanced hydrodynamic problems, instabilities, turbulence, and material properties. PPH can potentially be applied to the study of the properties of warm dense matter (WDM) as well. Exploration of the properties of warm dense matter such as equation of state, viscosity, conductivity is an emerging area of study focused on the behavior of matter at density near solid density (from 10% of solid density to slightly above solid density) and modest temperatures ({approx}1-10 eV). Conditions characteristic of WDM are difficult to obtain, and even more difficult to diagnose. One approach to producing WDM uses laser or particle beam heating of very small quantities of matter on timescales short compared to the subsequent hydrodynamic expansion timescales (isochoric heating) and a vigorous community of researchers are applying these techniques. Pulsed power hydrodynamic techniques, such as large convergence liner compression of a large volume, modest density, low temperature plasma to densities approaching solid density or through multiple shock compression and heating of normal density material between a massive, high density, energetic liner and a high density central 'anvil' are possible ways to reach relevant conditions. Another avenue to WDM conditions is through the explosion and subsequent expansion of a conductor (wire) against a high pressure (density) gas background (isobaric expansion) techniques. However, both techniques demand substantial energy, proper power conditioning and delivery, and an understanding of the hydrodynamic and instability processes that limit each technique. In this paper we will examine the challenges to pulsed power technology and to pulsed power systems presented by the opportunity to explore this interesting region of parameter space.

  11. Warm dense crystallography

    Science.gov (United States)

    Valenza, Ryan A.; Seidler, Gerald T.

    2016-03-01

    The intense femtosecond-scale pulses from x-ray free electron lasers (XFELs) are able to create and interrogate interesting states of matter characterized by long-lived nonequilibrium semicore or core electron occupancies or by the heating of dense phases via the relaxation cascade initiated by the photoelectric effect. We address here the latter case of "warm dense matter" (WDM) and investigate the observable consequences of x-ray heating of the electronic degrees of freedom in crystalline systems. We report temperature-dependent density functional theory calculations for the x-ray diffraction from crystalline LiF, graphite, diamond, and Be. We find testable, strong signatures of condensed-phase effects that emphasize the importance of wide-angle scattering to study nonequilibrium states. These results also suggest that the reorganization of the valence electron density at eV-scale temperatures presents a confounding factor to achieving atomic resolution in macromolecular serial femtosecond crystallography (SFX) studies at XFELs, as performed under the "diffract before destroy" paradigm.

  12. Diffusion of dark matter in a hot and dense nuclear environment

    CERN Document Server

    Cermeño, Marina; Silk, Joseph

    2015-01-01

    We calculate the mean free path in a hot and dense nuclear environment for a fermionic dark matter particle candidate interacting with nucleons via scalar and vector couplings. We determine the effects of density and temperature in the medium by using nuclear distribution functions to size the importance of the final state blocking. Our results show that stellar nuclear scenarios, where dark matter may be accreted, provide opacities several orders of magnitude larger than those for Standard Model neutrinos in the context of cooling of proto-neutron stars. We also show that in a diffusive approximation with couplings of Fermi's constant strength the obtained dark matter-nucleon crosss sections display the same sensitivity that upper limits constrained with collider searches in the mass region $m_\\chi \\lesssim$ 5 GeV.

  13. Constraining the State of Ultra-dense Matter with the Neutron Star Interior Composition Explorer

    Science.gov (United States)

    Bogdanov, Slavko

    2016-04-01

    [This presentation is submitted on behalf of the entire NICER Science Team] The state of cold matter at densities exceeding those of atomic nuclei remains one of the principal outstanding problems in modern physics. Neutron stars provide the only known setting in the universe where these physical conditions can be explored. Thermal X-ray radiation from the physical surface of a neutron star can serve as a powerful tool for probing the poorly understood behavior of the matter in the dense stellar interior. For instance, realistic modeling of the thermal X-ray modulations observed from rotation-powered millisecond pulsars can produce stringent constraints on the neutron star mass-radius relation, and by extension the state of supra-nuclear matter. I will describe the prospects for precision neutron star equation of state constraints with millisecond pulsars using the forthcoming Neutron Star Interior Composition Explorer (NICER) X-ray timing mission.

  14. Generation of strong magnetic fields in dense quark matter driven by the electroweak interaction of quarks

    CERN Document Server

    Dvornikov, Maxim

    2016-01-01

    We study the generation of strong large scale magnetic fields in dense quark matter. The magnetic field growth is owing to the magnetic field instability driven by the electroweak interaction of quarks. We discuss the situation when the chiral symmetry is unbroken in the degenerate quark matter. In this case we predict the amplification of the seed magnetic field $10^{12}\\,\\text{G}$ to the strengths $(10^{14}-10^{15})\\,\\text{G}$. In our analysis we use the typical parameters of the quark matter in the core of a hybrid star or in a quark star. We also discuss the application of the obtained results to describe the magnetic fields generation in magnetars.

  15. Ultrabright x-ray laser scattering for dynamic warm dense matter physics

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, L. B. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Univ. of California, Berkeley, CA (United States); Lee, H. J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Doppner, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Galtier, E. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Nagler, B. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Heimann, P. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Fortmann, C. [QuantumWise A/S, Koebenhavn (Denmark); LePape, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mao, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Millot, M. [Univ. of California, Berkeley, CA (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pak, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Turnbull, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chapman, D. A. [AWE plc, Reading (United Kingdom); Univ. of Warwick, Coventry (United Kingdom); Gericke, D. O. [AWE plc, Reading (United Kingdom); Vorberger, J. [Max Planck Institute for the Physics of Complex Systems, Dresden (Germany); White, T. [Univ. of Oxford, Oxford (United Kingdom); Gregori, G. [Univ. of Oxford, Oxford (United Kingdom); Wei, M. [General Atomics, San Diego, CA (United States); Barbrel, B. [Univ. of California, Berkeley, CA (United States); Falcone, R. W. [Univ. of California, Berkeley, CA (United States); Kao, C. -C. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Nuhn, H. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Welch, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Zastrau, U. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Friedrich-Schiller-Univ., Jena (Germany); Neumayer, P. [GSI Helmhltzzentrum fur Schwerionenforschung GmbH, Darmstadt (Germany); Hastings, J. B. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Glenzer, S. H. [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-03-23

    In megabar shock waves, materials compress and undergo a phase transition to a dense charged-particle system that is dominated by strong correlations and quantum effects. This complex state, known as warm dense matter, exists in planetary interiors and many laboratory experiments (for example, during high-power laser interactions with solids or the compression phase of inertial confinement fusion implosions). Here, we apply record peak brightness X-rays at the Linac Coherent Light Source to resolve ionic interactions at atomic (ångström) scale lengths and to determine their physical properties. Our in situ measurements characterize the compressed lattice and resolve the transition to warm dense matter, demonstrating that short-range repulsion between ions must be accounted for to obtain accurate structure factor and equation of state data. Additionally, the unique properties of the X-ray laser provide plasmon spectra that yield the temperature and density with unprecedented precision at micrometre-scale resolution in dynamic compression experiments.

  16. Confronting effective models for deconfinement in dense quark matter with lattice data

    CERN Document Server

    Andersen, Jens O; Naylor, William

    2015-01-01

    Ab initio numerical simulations of the thermodynamics of dense quark matter remain a challenge. Apart from the infamous sign problem, lattice methods have to deal with finite volume and discretization effects as well as with the necessity to introduce sources for symmetry-breaking order parameters. We study these artifacts in the Polyakov-loop-extended Nambu-Jona-Lasinio model, and compare its predictions to existing lattice data for cold and dense two-color matter with two flavors of Wilson quarks. To achieve even qualitative agreement with lattice data \\emph{requires} the introduction of two novel elements in the model: (i) explicit chiral symmetry breaking in the effective contact four-fermion interaction, referred to as the chiral twist, and (ii) renormalization of the Polyakov loop. The feedback of the dense medium to the gauge sector is modeled by a chemical-potential-dependent scale in the Polyakov-loop potential. In contrast to previously used analytical ans\\"atze, we determine its dependence on the c...

  17. The ion potential in warm dense matter: wake effects due to streaming degenerate electrons

    CERN Document Server

    Moldabekov, Zhandos; Bonitz, Michael; Ramazano, Tlekkabul

    2014-01-01

    The effective dynamically screened potential of a classical ion in a stationary flowing quantum plasma at finite temperature is investigated. This is a key quantity for thermodynamics and transport of dense plasmas in the warm dense matter regime. To compute this potential a linear response description of the electrons via the Mermin dielectric function is utilized with electron-electron collisions taken into account via a relaxation time approximation. The ion potential strongly deviates from the static Yukawa potential exhibiting the familiar oscillatory structure with attractive minima (wake potential). This potential is analyzed in detail for high-density plasmas with values of the Brueckner parameter in the range $0.1 \\le r_s \\le 1$, for a broad range of plasma temperature and electron streaming velocity. It is shown that wake effects become weaker with increasing temperature of the electrons. Finally, we obtain the minimal electron streaming velocity for which attraction between ions occurs. This veloci...

  18. Path Integral Monte Carlo and Density Functional Molecular Dynamics Simulations of Warm Dense Matter

    Science.gov (United States)

    Militzer, Burkhard; Driver, Kevin

    2011-10-01

    We analyze the applicability of two first-principles simulation techniques, path integral Monte Carlo (PIMC) and density functional molecular dynamics (DFT-MD), to study the regime of warm dense matter. We discuss the advantages as well as the limitations of each method and propose directions for future development. Results for dense, liquid helium, where both methods have been applied, demonstrate the range of each method's applicability. Comparison of the equations of state from simulations with analytical theories and free energy models show that DFT is useful for temperatures below 100000 K and then PIMC provides accurate results for all higher temperatures. We characterize the structure of the liquid in terms of pair correlation functions and study the closure of the band gap with increasing density and temperature. Finally, we discuss simulations of heavier elements and demonstrate the reliability are both methods in such cases with preliminary results.

  19. Guiding of relativistic electron beams in dense matter by longitudinally imposed strong magnetic fields

    CERN Document Server

    Bailly-Grandvaux, M; Bellei, C; Forestier-Colleoni, P; Fujioka, S; Giuffrida, L; Honrubia, J J; Batani, D; Bouillaud, R; Chevrot, M; Cross, J E; Crowston, R; Dorard, S; Dubois, J -L; Ehret, M; Gregori, G; Hulin, S; Kojima, S; Loyez, E; Marques, J -R; Morace, A; Nicolai, Ph; Roth, M; Sakata, S; Schaumann, G; Serres, F; Servel, J; Tikhonchuk, V T; Woolsey, N; Zhang, Z

    2016-01-01

    High-energy-density flows through dense matter are needed for effective progress in the production of laser-driven intense sources of energetic particles and radiation, in driving matter to extreme temperatures creating state regimes relevant for planetary or stellar science as yet inaccessible at the laboratory scale, or in achieving high-gain laser-driven thermonuclear fusion. When interacting at the surface of dense (opaque) targets, intense lasers accelerate relativistic electron beams which transport a significant fraction of the laser energy into the target depth. However, the overall laser-to-target coupling efficiency is impaired by the large divergence of the electron beam, intrinsic to the laser-plasma interaction. By imposing a longitudinal 600T laser-driven magnetic-field, our experimental results show guided >10MA-current of MeV-electrons in solid matter. Due to the applied magnetic field, the transported energy-density and the peak background electron temperature at the 60micron-thick targets re...

  20. Probing dense matter in compact star cores with radio pulsar data

    CERN Document Server

    Alford, Mark G

    2014-01-01

    Astrophysical observations of compact stars provide, in addition to collider experiments, the other big source of information on matter under extreme conditions. The largest and most precise data set about neutron stars is the timing data of radio pulsars. We show how this unique data can be used to learn about the ultra-dense matter in the compact star interior. The method relies on astro-seismology based on special global oscillation modes (r-modes) that emit gravitational waves. They would prevent pulsars from spinning with their observed high frequencies, unless the damping of these modes, determined by the microscopic properties of matter, can prevent this. We show that for each form of matter there is a distinct region in a frequency/spindown-rate diagram where r-modes can be present. We find that stars containing ungapped quark matter are consistent with both the observed radio and x-ray data, whereas, even when taking into account the considerable uncertainties, neutron star models with standard visco...

  1. Electron transport calculations in warm dense matter using scattering cross sections

    CERN Document Server

    Burrill, D J; Charest, M R J; Starrett, C E

    2015-01-01

    The Ziman formulation of electrical conductivity is tested in warm and hot dense matter using the pseudo-atom molecular dynamics method. Several implementation options that have been widely used in the literature are systematically tested through a comparison to accurate but expensive Kohn-Sham density functional theory molecular dynamics (KS-DFT-MD) calculations. The comparison is made for several elements and mixtures and for a wide range of temperatures and densities, and reveals a preferred method that generally gives very good agreement with the KSDFT-MD results, but at a fraction of the computational cost.

  2. Fast rotation of neutron stars and equation of state of dense matter

    CERN Document Server

    Haensel, P; Bejger, M

    2008-01-01

    Fast rotation of compact stars (at submillisecond period) and, in particular, their stability, are sensitive to the equation of state (EOS) of dense matter. Recent observations of XTE J1739-285 suggest that it contains a neutron star rotating at 1122 Hz (Kaaret et al. 2007). At such rotational frequency the effects of rotation on star's structure are significant. We study the interplay of fast rotation, EOS and gravitational mass of a submillisecond pulsar. We discuss the EOS dependence of spin-up to a submillisecond period, via mass accretion from a disk in a low-mass X-ray binary.

  3. 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.

  4. Neutrino-antineutrino pair production by a photon in a dense matter

    CERN Document Server

    Lobanov, A E

    2006-01-01

    The possibility of radiative effects that are due to interaction of fermions with a dense matter is investigated. Neutrino-antineutrino photo-production is studied. The rate of this process is calculated in the Furry picture. It is demonstrated that this effect does not disappear even if the medium refractive index is assumed to be equal to unity. The rate obtained strongly depends on the polarization states of the particles involved. This leads to evident spatial asymmetries, which may have certain consequences observable in astrophysical and cosmological studies.

  5. Optical conductivity of warm dense matter in wide frequency range within quantum statistical and kinetic approach

    CERN Document Server

    Veysman, M; Winkel, M; Reinholz, H

    2016-01-01

    Fundamental properties of warm dense matter are described by the dielectric function, which gives access to the frequency-dependent electrical conductivity, absorption, emission and scattering of radiation, charged particles stopping and further macroscopic properties. Different approaches to the dielectric function and the related dynamical collision frequency are compared in a wide frequency range. The high-frequency limit describing inverse bremsstrahlung and the low-frequency limit of the dc conductivity are considered. Sum rules and Kramers-Kronig relation are checked for the generalized linear response theory and the standard approach following kinetic theory. The results are discussed in application to aluminum, xenon and argon plasmas.

  6. The emerging WDM EPON

    CERN Document Server

    Radivojević, Mirjana

    2017-01-01

    This book proposes dynamic wavelength and bandwidth allocation (DWBA), a hybrid of time-division multiplexing (TDM) and wavelength-division multiplexing (WDM), which offers a solution for service providers faced with multiservice networks. It discusses different models, architectures and implementations and evaluates their performance.

  7. Road of warm dense noble metals to the plasma state: Ab initio theory of the ultrafast structural dynamics in warm dense matter

    Science.gov (United States)

    Kabeer, Fairoja Cheenicode; Zijlstra, Eeuwe S.; Garcia, Martin E.

    2014-03-01

    Intense ultrashort extreme ultraviolet (XUV) pulses can be used to create warm dense matter in the laboratory, which then develops to a plasma state. So far, however, it is unknown, whether this transition occurs via heat transfer from hot electrons to cold atoms or nonthermally due to a lattice instability. Here we computed the response of the phonon spectra of copper and silver to the presence of XUV-excited core holes and core holes together with very hot electrons. We found that the average interatomic bonds become stronger in the warm dense state. We discuss why these findings support the above-mentioned heat transfer scenario.

  8. Atomistic study of mixing at high Z / low Z interfaces at Warm Dense Matter Conditions

    Science.gov (United States)

    Haxhimali, Tomorr; Glosli, James; Rudd, Robert; Lawrence Livermore National Laboratory Team

    2016-10-01

    We use atomistic simulations to study different aspects of mixing occurring at an initially sharp interface of high Z and low Z plasmas in the Warm/Hot Dense Matter regime. We consider a system of Diamond (the low Z component) in contact with Ag (the high Z component), which undergoes rapid isochoric heating from room temperature up to 10 eV, rapidly changing the solids into warm dense matter at solid density. We simulate the motion of ions via the screened Coulomb potential. The electric field, the electron density and ionizations level are computed on the fly by solving Poisson equation. The spatially varying screening lengths computed from the electron cloud are included in this effective interaction; the electrons are not simulated explicitly. We compute the electric field generated at the Ag-C interface as well as the dynamics of the ions during the mixing process occurring at the plasma interface. Preliminary results indicate an anomalous transport of high Z ions (Ag) into the low Z component (C); a phenomenon that is partially related to the enhanced transport of ions due to the generated electric field. These results are in agreement with recent experimental observation on Au-diamond plasma interface. This work was performed under the auspices of the US Dept. of Energy by Lawrence Livermore National Security, LLC under Contract DE-AC52-07NA27344.

  9. Hot and dense matter in compact stars - from nuclei to quarks

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, Matthias

    2010-10-19

    This dissertation deals with the equation of state of hot and dense matter in compact stars, with special focus on first order phase transitions. A general classification of first order phase transitions is given and the properties of mixed phases are discussed. Aspects of nucleation and the role of local constraints are investigated. The derived theoretical concepts are applied to matter in neutron stars and supernovae, in the hadron-quark and the liquid-gas phase transition. For the detailed description of the liquid-gas phase transition a new nuclear statistical equilibrium model is developed. It is based on a thermodynamic consistent implementation of relativistic mean-field interactions and excluded volume effects. With this model different equation of state tables are calculated and the composition and thermodynamic properties of supernova matter are analyzed. As a first application numerical simulations of core-collapse supernovae are presented. For the hadron-quark phase transition two possible scenarios are studied in more detail. First the appearance of a new mixed phase in a proto neutron star and the implications on its evolution. In the second scenario the consequences of the hadron-quark transition in corecollapse supernovae are investigated. Simulations show that the appearance of quark matter has clear observable signatures and can even lead to the generation of an explosion. (orig.)

  10. Topology Change and Tensor Forces for the EoS of Dense Baryonic Matter

    CERN Document Server

    Lee, Hyun Kyu

    2013-01-01

    When skyrmions representing nucleons are put on crystal lattice and compressed to simulate high density, there is a transition above the normal nuclear matter density $n_0$ from a matter consisting of skyrmions with integer baryon charge to a state of half-skyrmions with half-integer baryon charge. We exploit this observation in an effective field theory formalism to access dense baryonic system. We find that the topology change involved implies a changeover from a Fermi liquid structure to a non-Fermi liquid with the chiral condensate in the nucleon "melted off." The $\\sim 80%$ of the nucleon mass that remains, invariant under chiral transformation, points to the origin of the (bulk of) proton mass that is not encoded in the standard mechanism of spontaneously broken chiral symmetry. The topology change engenders a drastic modification of the nuclear tensor forces, thereby nontrivially affecting the EoS, in particular, the symmetry energy, for compact star matter. It brings in stiffening of the EoS needed to...

  11. Thermal properties of hot and dense matter with finite range interactions

    CERN Document Server

    Constantinou, Constantinos; Prakash, Madappa; Lattimer, James M

    2015-01-01

    We explore the thermal properties of hot and dense matter using a model that reproduces the empirical properties of isospin symmetric and asymmetric bulk nuclear matter, optical model fits to nucleon-nucleus scattering data, heavy-ion flow data in the energy range 0.5-2 GeV/A, and the largest well-measured neutron star mass of 2 $\\rm{M}_\\odot$. Results of this model which incorporates finite range interactions through Yukawa type forces are contrasted with those of a zero-range Skyrme model that yields nearly identical zero-temperature properties at all densities for symmetric and asymmetric nucleonic matter and the maximum neutron star mass, but fails to account for heavy-ion flow data due to the lack of an appropriate momentum dependence in its mean field. Similarities and differences in the thermal state variables and the specific heats between the two models are highlighted. Checks of our exact numerical calculations are performed from formulas derived in the strongly degenerate and non-degenerate limits....

  12. Skyrmions, half-skyrmions and nucleon mass in dense baryonic matter

    CERN Document Server

    Ma, Yong-Liang; Lee, Hyun Kyu; Oh, Yongseok; Rho, Mannque

    2013-01-01

    We explore the hadron properties in dense baryonic matter in a unified way by using a Skyrme model constructed with an effective Lagrangian which includes the $\\rho$ and $\\omega$ vector mesons as hidden gauge bosons and is valid up to $O(p^4)$ in chiral expansion including the homogeneous Wess-Zumino terms. With the two input values of pion decay constant and the lowest lying vector meson mass which can be fixed in free space, all the other low energy constants in the effective Lagrangian are determined by their master formulas derived from holographic QCD models, which allows us to study the baryonic matter properties with no additional free parameters and thus without ambiguities. We find that the $\\omega$ field that figures in the homogeneous Wess-Zumino term plays a crucial role in the skyrmion structure and its matter properties. The most striking and intriguing observation is that the pion decay constant that smoothly drops with increasing density in the Skyrmion phase stops decreasing at $n_{1/2}^{}$ a...

  13. Beam Steering, Focusing and Compression for Warm-Dense Matter Experiments

    Science.gov (United States)

    Lidia, S. M.; Anders, A.; Cohen, R. H.; Coleman, J. E.; Dorf, M.; Gilson, E. P.; Grote, D. P.; Jung, J. Y.; Leitner, M.; Logan, B. G.; Roy, P. K.; Sefkow, A. B.; Seidl, P. A.; Waldron, W. L.; Welch, D. R.

    2008-11-01

    The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the Warm Dense Matter regime, using space-charge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Axial compression leading to ˜100X current amplification and simultaneous radial focusing have led to encouraging energy deposition approaching, but still short of, the intensities required for eV-range target heating experiments. We present measurements from the Neutralized Drift Compression Experiment to reach the necessary higher beam intensities, including: (1) axial compression and radial focusing; (2) spatial and temporal distribution of energy deposition at the target plane; and (3) centroid motion of the beam spot through the pulse.

  14. Effects of Dense Matter on Hadron Production in Heavy-Ion Collisions

    CERN Document Server

    Papp, G; Fái, G; Lévai, Peter; Zhang, Y; Papp, Gabor; Barnafoeldi, Gergely; Fai, George; Levai, Peter; Zhang, Yi

    2000-01-01

    The intrinsic transverse momentum distribution of partons in the nucleon can be used to explain a large amount of high-$p_T$ hadron and photon production data in high-energy nucleon-nucleon collisions at energies $\\sqrt{s} \\approx 20$ to 1800 GeV. However, proton-nucleus experiments at energies $\\approx 30$ GeV show an extra enhancement (Cronin effect) in the yield of photons and mesons compared to a simple extrapolation of the proton-proton data. This enhancement is due to the effect of the dense hadronic matter encountered by the projectile proton in the nuclear environment. We discuss the origin and the properties of the nuclear enhancement.

  15. Dense Baryonic Matter in Hidden Local Symmetry Approach: Half-Skyrmions and Nucleon Mass

    CERN Document Server

    Ma, Yong-Liang; Lee, Hyun Kyu; Oh, Yongseok; Park, Byung-Yoon; Rho, Mannque

    2013-01-01

    Hadron properties in dense medium are treated in a unified way in a skyrmion model constructed with an effective Lagrangian, in which the rho and omega vector mesons are introduced as hidden gauge bosons, valid up to O(p^4) terms in chiral expansion including the homogeneous Wess-Zumino terms. All the low energy constants - apart from f_pi and m_rho - are fixed by the master formula derived from the relation between 5-D hQCD and 4-D HLS. This allows one to pin down the density n_1/2 at which the skyrmions in medium fractionize into half-skyrmions, bringing in a drastic change in the EoS of dense matter. We find that the U(1) field that figures in the CS term in the hQCD action or equivalently the omega field in the hWZ term in the dimensionally reduced HLS action plays a crucial role in the half-skyrmion phase. The importance of the omega degree of freedom may be connected to what happens in the instanton structure of elementary baryon noticed in hQCD. The most striking and intriguing in what is found in the ...

  16. Effect of a strong magnetic field on the energy yield of nuclear reactions in dense nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Sekerzhitskii, V.S. [Pushkin Pedagogical Institute, Brest (Belarus)

    1995-01-01

    According to modern concepts, the electron-neutron-nuclear (Aen) phase of dense highly degenerate matter can be realized in the shells of neutron stars. This phase has relatively stable and absolutely stable states of thermodynamic equilibrium. Strong magnetic fields can exist in neutron stars. For this reason, analysis of their effect on the characteristics of the Aen phase is of great interest. It is specially important to study the influence of strong magnetic fields on the energy yield of nuclear reactions in dense nuclear matter because the transition to the absolute equilibrium state proceeds through these reactions.

  17. Study of hot and dense nuclear matter in effective QCD model

    CERN Document Server

    Islam, Chowdhury Aminul

    2016-01-01

    In this thesis we use various effective QCD models to investigate hot and dense nuclear matter created in heavy ion collisions. To characterize such matter, we mainly exploit correlation functions and some of the associated spectral properties. We explore the vector meson current-current correlation function with and without the influence of vector interaction in Nambu\\textendash Jona-Lasinio (NJL) model and also in its Polyakov loop extended version (PNJL). As a spectral property we have computed the dilepton rate which is found to be enhanced in strongly interacting QGP (sQGP) as compared to the Born rate in a weakly coupled QGP. We further consider the idea of entanglement between the chiral and confinement dynamics through the entangled PNJL (EPNJL) model and re-explore the vector spectral function and the spectral property such as the dilepton production rate studied in our earlier effort. Because of the strong entanglement, the coupling strengths run with the temperature and chemical potential. The impl...

  18. Proton acceleration experiments and warm dense matter research using high power lasers

    Energy Technology Data Exchange (ETDEWEB)

    Roth, M; Alber, I; Guenther, M; Harres, K [Institut fuer Kernphysik, Technische Universitaet Darmstadt, 64289 Darmstadt (Germany); Bagnoud, V [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Brown, C R D [Plasma Physics Group, Imperial College London, SW7 2BZ (United Kingdom); Clarke, R; Heathcote, R; Li, B [STFC, Rutherford Appleton Laboratory (RAL), Chilton, Didcot, OX14 OQX (United Kingdom); Daido, H [Photo Medical Research Center, JAEA, Kizugawa-City, Kyoto 619-0215 (Japan); Fernandez, J; Flippo, K; Gaillard, S; Gauthier, C [Los Alamos National Laboratory (LANL), Los Alamos, NM 87545 (United States); Geissel, M [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Glenzer, S; Kritcher, A; Kugland, N; LePape, S [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Gregori, G, E-mail: markus.roth@physik.tu-darmstadt.d [Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)

    2009-12-15

    The acceleration of intense proton and ion beams by ultra-intense lasers has matured to a point where applications in basic research and technology are being developed. Crucial for harvesting the unmatched beam parameters driven by the relativistic electron sheath is the precise control of the beam. In this paper we report on recent experiments using the PHELIX laser at GSI, the VULCAN laser at RAL and the TRIDENT laser at LANL to control and use laser accelerated proton beams for applications in high energy density research. We demonstrate efficient collimation of the proton beam using high field pulsed solenoid magnets, a prerequisite to capture and transport the beam for applications. Furthermore, we report on two campaigns to use intense, short proton bunches to isochorically heat solid targets up to the warm dense matter state. The temporal profile of the proton beam allows for rapid heating of the target, much faster than the hydrodynamic response time thereby creating a strongly coupled plasma at solid density. The target parameters are then probed by x-ray Thomson scattering to reveal the density and temperature of the heated volume. This combination of two powerful techniques developed during the past few years allows for the generation and investigation of macroscopic samples of matter in states present in giant planets or the interior of the earth.

  19. Skyrmions, half-skyrmions and nucleon mass in dense baryonic matter

    Science.gov (United States)

    Ma, Yong-Liang; Harada, Masayasu; Lee, Hyun Kyu; Oh, Yongseok; Rho, Mannque

    2014-04-01

    We explore the hadron properties in dense baryonic matter in a unified way by using a Skyrme model constructed with an effective Lagrangian which includes the ρ and ω vector mesons as hidden gauge bosons and is valid up to O(p4) in chiral expansion including the homogeneous Wess-Zumino terms. With the two input values of pion decay constant and the lowest lying vector meson mass which can be fixed in free space, all the other low energy constants in the effective Lagrangian are determined by their master formulas derived from holographic QCD models, which allows us to study the baryonic matter properties with no additional free parameters and thus without ambiguities. We find that the ω field that figures in the homogeneous Wess-Zumino term plays a crucial role in the skyrmion structure and its matter properties. The most striking and intriguing observation is that the pion decay constant that smoothly drops with increasing density in the Skyrmion phase stops decreasing at n1/2 at which the skyrmions in medium fractionize into half-skyrmions and remains nearly constant in the half-skyrmion phase. In accordance with the large Nc consideration, the baryon mass also stays non-scaling in the half-skyrmion phase. This feature is supported by the nuclear effective field theory with the parameters of the Lagrangian scaling modified at the skyrmion-half-skyrmion phase transition. Our exploration also uncovers the crucial role of the ω meson in multi-baryon systems as well as in the structure of a single skyrmion.

  20. Single-shot mega-electronvolt ultrafast electron diffraction for structure dynamic studies of warm dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Mo, M. Z., E-mail: mmo09@slac.stanford.edu; Shen, X.; Chen, Z.; Li, R. K.; Dunning, M.; Zheng, Q.; Weathersby, S. P.; Reid, A. H.; Coffee, R.; Makasyuk, I.; Edstrom, S.; McCormick, D.; Jobe, K.; Hast, C.; Glenzer, S. H.; Wang, X. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Sokolowski-Tinten, K. [Faculty of Physics and Centre for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Lotharstrasse 1, D-47048 Duisburg (Germany)

    2016-11-15

    We have developed a single-shot mega-electronvolt ultrafast-electron-diffraction system to measure the structural dynamics of warm dense matter. The electron probe in this system is featured by a kinetic energy of 3.2 MeV and a total charge of 20 fC, with the FWHM pulse duration and spot size at sample of 350 fs and 120 μm respectively. We demonstrate its unique capability by visualizing the atomic structural changes of warm dense gold formed from a laser-excited 35-nm freestanding single-crystal gold foil. The temporal evolution of the Bragg peak intensity and of the liquid signal during solid-liquid phase transition are quantitatively determined. This experimental capability opens up an exciting opportunity to unravel the atomic dynamics of structural phase transitions in warm dense matter regime.

  1. Results from an Orion proton heating experiment for Warm Dense Matter studies

    Science.gov (United States)

    Allan, Peter; James, Steven; Brown, Colin; Hobbs, Lauren; Hill, Matthew; Hoarty, David; Chen, Hui; Hazi, Andy; AWE Team; LLNL Team

    2014-10-01

    The properties of warm dense matter covering densities and temperatures in the ranges 0.1-10x solid and 1-100eV, fall between ideal plasma and condensed matter theories. Studies have highlighted uncertainties in EoS predictions using methods based on the Thomas-Fermi and ion-cell models. In particular, such models predict large departures from ideal gas behaviour for low Z material at low densities and temperatures. In an extension of previous work, material has been isochorically heated using short-pulse laser-generated proton beams. Here, the method of Foord et al. was used toinfer isentropes oflow Z materials and provide data to validate model predictions. Earlier measurements were limited by the eV backlighterenergy to relatively low densities and pressures below 1.5Mbar, and were conducted in cylindrical geometry. More recent experiments performed at the Orion laser use a parabolic crystal imaging system in order to measure to higher pressures by probing planar expansion of aluminium foils at 1.8keV. The imaging system is described and results are presented showing a spatial resolution of 6um, which was then streaked to give temporal resolution of 10ps. Preliminary analysis of the foil expansion indicates a peak temperature of 30eV. The proton and ion spectra used to heat the sample were measured by a magnetic spectrometer and a Thomson parabola. These results are presented and the effect on the measured expansion discussed. Plans for future measurements are discussed in the light of results obtained so far.

  2. Short intense ion pulses for materials and warm dense matter research

    CERN Document Server

    Seidl, Peter A; Lidia, Steven M; Persaud, Arun; Stettler, Matthew; Takakuwa, Jeffrey H; Waldron, William L; Schenkel, Thomas; Barnard, John J; Friedman, Alex; Grote, David P; Davidson, Ronald C; Gilson, Erik P; Kaganovich, Igor D

    2015-01-01

    We have commenced experiments with intense short pulses of ion beams on the Neutralized Drift Compression Experiment-II at Lawrence Berkeley National Laboratory, by generating beam spots size with radius r < 1 mm within 2 ns FWHM and approximately 10^10 ions/pulse. To enable the short pulse durations and mm-scale focal spot radii, the 1.2 MeV Li+ ion beam is neutralized in a 1.6-meter drift compression section located after the last accelerator magnet. An 8-Tesla short focal length solenoid compresses the beam in the presence of the large volume plasma near the end of this section before the target. The scientific topics to be explored are warm dense matter, the dynamics of radiation damage in materials, and intense beam and beam-plasma physics including selected topics of relevance to the development of heavy-ion drivers for inertial fusion energy. Here we describe the accelerator commissioning and time-resolved ionoluminescence measurements of yttrium aluminium perovskite using the fully integrated accel...

  3. Progress in beam focusing and compression for warm-dense matter experiments

    Science.gov (United States)

    Seidl, P. A.; Anders, A.; Bieniosek, F. M.; Barnard, J. J.; Calanog, J.; Chen, A. X.; Cohen, R. H.; Coleman, J. E.; Dorf, M.; Gilson, E. P.; Grote, D. P.; Jung, J. Y.; Leitner, M.; Lidia, S. M.; Logan, B. G.; Ni, P.; Roy, P. K.; Van den Bogert, K.; Waldron, W. L.; Welch, D. R.

    2009-07-01

    The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the warm-dense matter regime, using space-charge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Longitudinal beam compression by large factors has been demonstrated in the Neutralized Drift Compression Experiment (NDCX) with controlled ramps and forced neutralization. Using an injected 30-mA K + ion beam with initial kinetic energy 0.3 MeV, axial compression leading to ˜50-fold current amplification and simultaneous radial focusing to beam radii of a few mm have led to encouraging energy deposition approaching the intensities required for eV-range target heating experiments. We discuss the status of several improvements to our Neutralized Drift Compression Experiment and associated beam diagnostics that are under development to reach the necessary higher beam intensities, including (1) greater axial compression via a longer velocity ramp using a new bunching module with approximately twice the available volt seconds (Vs); (2) improved centroid control via beam steering dipoles to mitigate aberrations in the bunching module; (3) time-dependent focusing elements to correct considerable chromatic aberrations; and (4) plasma injection improvements to establish a plasma density always greater than the beam density, expected to be >10 13 cm -3.

  4. Short intense ion pulses for materials and warm dense matter research

    Science.gov (United States)

    Seidl, Peter A.; Persaud, Arun; Waldron, William L.; Barnard, John J.; Davidson, Ronald C.; Friedman, Alex; Gilson, Erik P.; Greenway, Wayne G.; Grote, David P.; Kaganovich, Igor D.; Lidia, Steven M.; Stettler, Matthew; Takakuwa, Jeffrey H.; Schenkel, Thomas

    2015-11-01

    We have commenced experiments with intense short pulses of ion beams on the Neutralized Drift Compression Experiment-II at Lawrence Berkeley National Laboratory, by generating beam spots size with radius r<1 mm within 2 ns FWHM and approximately 1010 ions/pulse. To enable the short pulse durations and mm-scale focal spot radii, the 1.2 MeV Li+ ion beam is neutralized in a 1.6-meter drift compression section located after the last accelerator magnet. An 8-Tesla short focal length solenoid compresses the beam in the presence of the large volume plasma near the end of this section before the target. The scientific topics to be explored are warm dense matter, the dynamics of radiation damage in materials, and intense beam and beam-plasma physics including selected topics of relevance to the development of heavy-ion drivers for inertial fusion energy. Here we describe the accelerator commissioning and time-resolved ionoluminescence measurements of yttrium aluminum perovskite using the fully integrated accelerator and neutralized drift compression components.

  5. Short intense ion pulses for materials and warm dense matter research

    Energy Technology Data Exchange (ETDEWEB)

    Seidl, Peter A., E-mail: PASeidl@lbl.gov [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Persaud, Arun; Waldron, William L. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Barnard, John J. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Davidson, Ronald C. [Princeton Plasma Physics Laboratory, Princeton, NJ (United States); Friedman, Alex [Lawrence Livermore National Laboratory, Livermore, CA (United States); Gilson, Erik P. [Princeton Plasma Physics Laboratory, Princeton, NJ (United States); Greenway, Wayne G. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Grote, David P. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Kaganovich, Igor D. [Princeton Plasma Physics Laboratory, Princeton, NJ (United States); Lidia, Steven M.; Stettler, Matthew; Takakuwa, Jeffrey H.; Schenkel, Thomas [Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2015-11-11

    We have commenced experiments with intense short pulses of ion beams on the Neutralized Drift Compression Experiment-II at Lawrence Berkeley National Laboratory, by generating beam spots size with radius r<1 mm within 2 ns FWHM and approximately 10{sup 10} ions/pulse. To enable the short pulse durations and mm-scale focal spot radii, the 1.2 MeV Li{sup +} ion beam is neutralized in a 1.6-meter drift compression section located after the last accelerator magnet. An 8-Tesla short focal length solenoid compresses the beam in the presence of the large volume plasma near the end of this section before the target. The scientific topics to be explored are warm dense matter, the dynamics of radiation damage in materials, and intense beam and beam-plasma physics including selected topics of relevance to the development of heavy-ion drivers for inertial fusion energy. Here we describe the accelerator commissioning and time-resolved ionoluminescence measurements of yttrium aluminum perovskite using the fully integrated accelerator and neutralized drift compression components.

  6. A k-{\\varepsilon} turbulence closure model of an isothermal dry granular dense matter

    Science.gov (United States)

    Fang, Chung

    2016-07-01

    The turbulent flow characteristics of an isothermal dry granular dense matter with incompressible grains are investigated by the proposed first-order k-{\\varepsilon} turbulence closure model. Reynolds-filter process is applied to obtain the balance equations of the mean fields with two kinematic equations describing the time evolutions of the turbulent kinetic energy and dissipation. The first and second laws of thermodynamics are used to derive the equilibrium closure relations satisfying turbulence realizability conditions, with the dynamic responses postulated by a quasi-linear theory. The established closure model is applied to analyses of a gravity-driven stationary flow down an inclined moving plane. While the mean velocity decreases monotonically from its value on the moving plane toward the free surface, the mean porosity increases exponentially; the turbulent kinetic energy and dissipation evolve, respectively, from their minimum and maximum values on the plane toward their maximum and minimum values on the free surface. The evaluated mean velocity and porosity correspond to the experimental outcomes, while the turbulent dissipation distribution demonstrates a similarity to that of Newtonian fluids in turbulent shear flows. When compared to the zero-order model, the turbulent eddy evolution tends to enhance the transfer of the turbulent kinetic energy and plane shearing across the flow layer, resulting in more intensive turbulent fluctuation in the upper part of the flow. Solid boundary as energy source and sink of the turbulent kinetic energy becomes more apparent in the established first-order model.

  7. Quantum molecular dynamics study of expanded beryllium: evolution from warm dense matter to atomic fluid.

    Science.gov (United States)

    Li, Dafang; Liu, Haitao; Zeng, Siliang; Wang, Cong; Wu, Zeqing; Zhang, Ping; Yan, Jun

    2014-07-31

    By performing quantum molecular dynamics (QMD) simulations, we investigate the equation of states, electrical and optical properties of the expanded beryllium at densities two to one-hundred lower than the normal solid density, and temperatures ranging from 5000 to 30000 K. With decreasing the density of Be, the optical response evolves from the one characteristic of a simple metal to the one of an atomic fluid. By fitting the optical conductivity spectra with the Drude-Smith model, it is found that the conducting electrons become localized at lower densities. In addition, the negative derivative of the electrical resistivity on temperature at density about eight lower than the normal solid density demonstrates that the metal to nonmetal transition takes place in the expanded Be. To interpret this transition, the electronic density of states is analyzed systematically. Furthermore, a direct comparison of the Rosseland opacity obtained by using QMD and the standard opacity code demonstrates that QMD provides a powerful tool to validate plasma models used in atomic physics approaches in the warm dense matter regime.

  8. Dense baryonic matter in the hidden local symmetry approach: Half-skyrmions and nucleon mass

    Science.gov (United States)

    Ma, Yong-Liang; Harada, Masayasu; Lee, Hyun Kyu; Oh, Yongseok; Park, Byung-Yoon; Rho, Mannque

    2013-07-01

    Hadron properties in dense medium are treated in a unified way in a skyrmion model constructed with an effective Lagrangian, in which the ρ and ω vector mesons are introduced as hidden gauge bosons, valid up to O(p4) terms in chiral expansion including the homogeneous Wess-Zumino terms. All the low energy constants of the Lagrangian—apart from the pion decay constant and the vector meson mass—are fixed by the master formula derived from the relation between the five-dimensional holographic QCD and the four-dimensional hidden local symmetry Lagrangian. This Lagrangian allows one to pin down the density n1/2 at which the skyrmions in medium fractionize into half-skyrmions, bringing in a drastic change in the equation of state of dense baryonic matter. We find that the U(1) field that figures in the Chern-Simons term in the five-dimensional holographic QCD action or equivalently the ω field in the homogeneous Wess-Zumino term in the dimensionally reduced hidden local symmetry action plays a crucial role in the half-skyrmion phase. The importance of the ω degree of freedom may be connected to what happens in the instanton structure of elementary baryon noticed in holographic QCD. The most striking and intriguing in what is found in the model is that the pion decay constant that smoothly drops with increasing density in the skyrmion phase stops decreasing at n1/2 and remains nearly constant in the half-skyrmion phase. In accordance with the large Nc consideration, the baryon mass also stays nonscaling in the half-skyrmion phase. This feature which is reminiscent of the parity-doublet baryon model with a chirally invariant mass m0 is supported by the nuclear effective field theory with the parameters of the Lagrangian scaling modified at the skyrmion-half-skyrmion phase transition. It also matches with one-loop renormalization group analysis based on hidden local symmetry. A link between a nonvanishing m0 and the origin of nucleon mass distinctive from

  9. X-ray Emission from Supernovae in Dense Circumstellar Matter Environments: a Search for Collisionless Shocks

    Science.gov (United States)

    Ofek, E. O.; Fox, D.; Cenko, Stephen B.; Sullivan, M; Gnat, O.; Frail, D. A.; Horesh, A.; Corsi, A.; Quimby, R. M.; Gehrels, N.; Kulkarni, S. R.; Gal-Yam, A.; Nugent, P. E.; Yaron, O.; Fillippenko, A. V; Kasliwal, M. M.; Bildsten, L.; Bloom, J. S.; Poznanski, D.; Arcavi, I.; Laher, R. R.; Levitan, D.; Sesar, B.; Surace, J..

    2013-01-01

    The optical light curve of some supernovae (SNe) may be powered by the outward diffusion of the energy deposited by the explosion shock (the so-called shock breakout) in optically thick (Tau approx > 30) circumstellar matter (CSM). Recently, it was shown that the radiation-mediated and radiation-dominated shock in an optically thick wind must transform into a collisionless shock and can produce hard X-rays. The X-rays are expected to peak at late times, relative to maximum visible light. Here we report on a search, using Swift/XRT and Chandra, for X-ray emission from 28 SNe that belong to classes whose progenitors are suspected to be embedded in dense CSM. Our sample includes 19 Type IIn SNe, one Type Ibn SN, and eight hydrogen-poor superluminous SNe (SLSN-I such as SN 2005ap). Two SNe (SN 2006jc and SN 2010jl) have X-ray properties that are roughly consistent with the expectation for X-rays from a collisionless shock in optically thick CSM. However, the X-ray emission from SN 2006jc can also be explained as originating in an optically thin region. Thus, we propose that the optical light curve of SN 2010jl is powered by shock breakout in CSM. We suggest that two other events (SN 2010al and SN 2011ht) were too X-ray bright during the SN maximum optical light to be explained by the shock-breakout model.We conclude that the light curves of some, but not all, SNe IIn/Ibn are powered by shock breakout in CSM. For the rest of the SNe in our sample, including all of the SLSN-I events, our X-ray limits are not deep enough and were typically obtained too early (i.e., near the SN maximum light) for definitive conclusions about their nature. Late-time X-ray observations are required in order to further test whether these SNe are indeed embedded in dense CSM. We review the conditions required for a shock breakout in a wind profile. We argue that the timescale, relative to maximum light, for the SN to peak in X-rays is a probe of the column density and the density profile above

  10. Importance of finite-temperature exchange correlation for warm dense matter calculations

    Science.gov (United States)

    Karasiev, Valentin V.; Calderín, Lázaro; Trickey, S. B.

    2016-06-01

    The effects of an explicit temperature dependence in the exchange correlation (XC) free-energy functional upon calculated properties of matter in the warm dense regime are investigated. The comparison is between the Karasiev-Sjostrom-Dufty-Trickey (KSDT) finite-temperature local-density approximation (TLDA) XC functional [Karasiev et al., Phys. Rev. Lett. 112, 076403 (2014), 10.1103/PhysRevLett.112.076403] parametrized from restricted path-integral Monte Carlo data on the homogeneous electron gas (HEG) and the conventional Monte Carlo parametrization ground-state LDA XC [Perdew-Zunger (PZ)] functional evaluated with T -dependent densities. Both Kohn-Sham (KS) and orbital-free density-functional theories are used, depending upon computational resource demands. Compared to the PZ functional, the KSDT functional generally lowers the dc electrical conductivity of low-density Al, yielding improved agreement with experiment. The greatest lowering is about 15% for T =15 kK. Correspondingly, the KS band structure of low-density fcc Al from the KSDT functional exhibits a clear increase in interband separation above the Fermi level compared to the PZ bands. In some density-temperature regimes, the deuterium equations of state obtained from the two XC functionals exhibit pressure differences as large as 4% and a 6% range of differences. However, the hydrogen principal Hugoniot is insensitive to the explicit XC T dependence because of cancellation between the energy and pressure-volume work difference terms in the Rankine-Hugoniot equation. Finally, the temperature at which the HEG becomes unstable is T ≥7200 K for the T -dependent XC, a result that the ground-state XC underestimates by about 1000 K.

  11. Generation and characterization of warm dense matter isochorically heated by laser-induced relativistic electrons in a wire target

    Science.gov (United States)

    Schönlein, A.; Boutoux, G.; Pikuz, S.; Antonelli, L.; Batani, D.; Debayle, A.; Franz, A.; Giuffrida, L.; Honrubia, J. J.; Jacoby, J.; Khaghani, D.; Neumayer, P.; Rosmej, O. N.; Sakaki, T.; Santos, J. J.; Sauteray, A.

    2016-05-01

    We studied the interaction of a high-intensity laser with mass-limited Ti-wires. The laser was focused up to 7× 1020 \\text{W/cm}2 , with contrast of 10-10 to produce relativistic electrons. High-spatial-resolution X-ray spectroscopy was used to measure isochoric heating induced by hot electrons propagating along the wire up to 1 mm depth. For the first time it was possible to distinguish surface target regions heated by mixed plasma mechanisms from those heated only by the hot electrons that generate warm dense matter with temperatures up to 50 eV. Our results are compared to simulations that highlight both the role of electron confinement inside the wire and the importance of resistive stopping powers in warm dense matter.

  12. Betatron x-rays from laser plasma accelerators: a new probe for warm dense matter at LCLS

    Science.gov (United States)

    Albert, Felicie

    2016-10-01

    Betatron x-ray radiation, driven by electrons from laser-wakefield acceleration, has unique properties to probe high energy density (HED) plasmas and warm dense matter. Betatron radiation is produced when relativistic electrons oscillate in the plasma wake of a laser pulse. Its properties are similar to those of synchrotron radiation, with a 1000 fold shorter pulse. This presentation will focus on the experimental challenges and results related to the development of betatron radiation for x-ray absorption spectroscopy of HED matter at large-scale laser facilities. A detailed presentation of the source mechanisms and characteristics in the blowout regime of laser-wakefield acceleration will be followed by a description of recent experiments performed at the Linac Coherent Light Source (LCLS). At LCLS, we have recently commissioned the betatron x-ray source driven by the MEC short pulse laser (1 J, 40 fs). The source is used as a probe for investigating the X-ray absorption near edge structure (XANES) spectrum at the K- or L-edge of iron and silicon oxide driven to a warm dense matter state (temperature of a few eV and solid densities). The driver is either LCLS itself or an optical laser. These experiments demonstrate the capability to study the electron-ion equilibration mechanisms in warm dense matter with sub-picosecond resolution. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, and supported by the Laboratory Directed research and development program under tracking codes 13-LW-076, 16-ERD-041 and by the Office of Fusion Energy Sciences under SCW1476 and SCW1569.

  13. Proceedings of RIKEN BNL Research Center Workshop: P- and CP-odd Effects in Hot and Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, A.; Fukushima, K.; Kharzeev, D.; Warringa, H.; Voloshin, S.

    2010-04-26

    This volume contains the proceedings of the RBRC/CATHIE workshop on 'P- and CP-odd Effects in Hot and Dense Matter' held at the RIKEN-BNL Research Center on April 26-30, 2010. The workshop was triggered by the experimental observation of charge correlations in heavy ion collisions at RHIC, which were predicted to occur due to local parity violation (P- and CP-odd fluctuations) in hot and dense QCD matter. This experimental result excited a significant interest in the broad physics community, inspired a few alternative interpretations, and emphasized the need for a deeper understanding of the role of topology in QCD vacuum and in hot and dense quark-gluon matter. Topological effects in QCD are also closely related to a number of intriguing problems in condensed matter physics, cosmology and astrophysics. We therefore felt that a broad cross-disciplinary discussion of topological P- and CP-odd effects in various kinds of matter was urgently needed. Such a discussion became the subject of the workshop. Specific topics discussed at the workshop include the following: (1) The current experimental results on charge asymmetries at RHIC and the physical interpretations of the data; (2) Quantitative characterization of topological effects in QCD matter including both analytical (perturbative and non-perturbative using gauge/gravity duality) and numerical (lattice-QCD) calculations; (3) Topological effects in cosmology of the Early Universe (including baryogenesis and dark energy); (4) Topological effects in condensed matter physics (including graphene and superfiuids); and (5) Directions for the future experimental studies of P- and CP-odd effects at RHIC and elsewhere. We feel that the talks and intense discussions during the workshop were extremely useful, and resulted in new ideas in both theory and experiment. We hope that the workshop has contributed to the progress in understanding the role of topology in QCD and related fields. We thank all the speakers and

  14. Optical conductivity of warm dense matter within a wide frequency range using quantum statistical and kinetic approaches

    Science.gov (United States)

    Veysman, M.; Röpke, G.; Winkel, M.; Reinholz, H.

    2016-07-01

    Fundamental properties of warm dense matter are described by the dielectric function, which gives access to the frequency-dependent electrical conductivity; absorption, emission, and scattering of radiation; charged particles stopping; and further macroscopic properties. Different approaches to the dielectric function and the related dynamical collision frequency are compared in a wide frequency range. The high-frequency limit describing inverse bremsstrahlung and the low-frequency limit of the dc conductivity are considered. Sum rules and Kramers-Kronig relation are checked for the generalized linear response theory and the standard approach following kinetic theory. The results are discussed in application to aluminum, xenon, and argon plasmas.

  15. Formation of dense partonic matter in relativistic nucleus-nucleus collisions at RHIC: Experimental evaluation by the PHENIX collaboration

    CERN Document Server

    Adcox, K; Ajitanand, N N; Akiba, Y; Alexander, J; Aphecetche, L; Arai, Y; Aronson, S H; Averbeck, R; Awes, T C; Barish, K N; Barnes, P D; Barrette, J; Bassalleck, B; Bathe, S; Baublis, V; Bazilevsky, A; Belikov, S V; Bellaiche, F G; Belyaev, S T; Bennett, M J; Berdnikov, Yu A; Botelho, S S; Brooks, M L; Brown, D S; Bruner, N L; Bucher, D; Büsching, H; Bumazhnov, V A; Bunce, G M; Burward-Hoy, J M; Butsyk, S; Carey, T A; Chand, P; Chang, J; Chang, W C; Chavez, L L; Chernichenko, S K; Chi, C Y; Chiba, J; Chiu, M; Choudhury, R K; Christ, T; Chujo, T; Chung, M S; Chung, P; Cianciolo, V; Cole, B A; D'Enterria, D G; Dávid, G; Delagrange, H; Denisov, A; Deshpande, A A; Desmond, E J; Dietzsch, O; Dinesh, B V; Drees, A; Durum, A A; Dutta, D; Ebisu, K; Efremenko, Yu V; El-Chenawi, K F; Enyo, H; Esumi, S C; Ewell, L A; Ferdousi, T; Fields, D E; Fokin, S L; Fraenkel, Zeev; Franz, A; Frawley, A D; Fung, S Y; Garpman, S; Ghosh, T K; Glenn, A; Godoi, A L; Goto, Y; Greene, S V; Grosse-Perdekamp, M; Sen-Gupta, S K; Guryn, W; Gustafsson, Hans Åke; Haggerty, J S; Hamagaki, H; Hansen, A G; Hara, H; Hartouni, E P; Hayano, R S; Hayashi, N; He, X; Hemmick, T K; Heuser, J M; Hill, J C; Ho, D S; Homma, K; Hong, B; Hoover, A; Ichihara, T; Imai, K; Ippolitov, M S; Ishihara, M; Jacak, B V; Jang, W Y; Jia, J; Johnson, B M; Johnson, S C; Joo, K S; Kametani, S; Kang, J H; Kann, M; Kapoor, S S; Kelly, S; Khachaturov, B A; Khanzadeev, A V; Kikuchi, J; Kim, D J; Kim, H J; Kim, S Y; Kim, Y G; Kinnison, W W; Kistenev, E P; Kiyomichi, A; Klein-Bösing, C; Klinksiek, S A; Kochenda, L M; Kochetkov, D; Kochetkov, V; Köhler, D; Kohama, T; Kozlov, A; Kroon, P J; Kurita, K; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R A; Lajoie, J G; Lauret, J; Lebedev, A; Lee, D M; Leitch, M J; Li, X H; Li, Z; Lim, D J; Liu, M X; Liu, X; Liu Zu Ping; Maguire, C F; Mahon, J R; Makdisi, Y I; Man'ko, V I; Mao, Y; Mark, S K; Markacs, S; Martínez, G; Marx, M D; Masaike, A; Matathias, F; Matsumoto, T; McGaughey, P L; Melnikov, E A; Merschmeyer, M; Messer, F; Messer, M; Miake, Y; Miller, T E; Milov, A M; Mioduszewski, S; Mischke, R E; Mishra, G C; Mitchell, J T; Mohanty, A K; Morrison, D P; Moss, J M; Muhlbacher, F; Muniruzzaman, M; Murata, J; Nagamiya, S; Nagasaka, Y; Nagle, J L; Nakada, Y; Nandi, B K; Newby, J; Nikkinen, L; Nilsson, P O; Nishimura, S; Nyanin, A S; Nystrand, J; O'Brien, E; Ogilvie, C A; Ohnishi, H; Ojha, I D; Ono, M; Onuchin, V A; Oskarsson, A; Österman, L; Otterlund, I; Oyama, K; Paffrath, L; Palounek, A P T; Pantuev, V S; Papavassiliou, V; Pate, S F; Peitzmann, Thomas; Petridis, A; Pinkenburg, C H; Pisani, R P; Pitukhin, P; Plasil, F; Pollack, M E; Pope, K; Purschke, M L; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Rosati, M; Rose, A A; Ryu, S S; Saitô, N; Sakaguchi, A; Sakaguchi, T; Sako, H; Sakuma, T; Samsonov, V; Sangster, T C; Santo, R; Sato, H D; Sato, S; Sawada, S; Schlei, B R; Schutz, Y; Semenov, V; Seto, R K; Shea, T K; Shein, I V; Shibata, T A; Shigaki, K; Shiina, T; Shin, Y H; Sibiryak, Yu; Silvermyr, D; Sim, K S; Simon-Gillo, J; Singh, C P; Singh, V; Sivertz, M; Soldatov, A; Soltz, R A; Sørensen, S; Stankus, P W; Starinsky, N; Steinberg, P; Stenlund, E; Ster, A; Stoll, S P; Sugioka, M; Sugitate, T; Sullivan, J P; Sumi, Y; Sun, Z; Suzuki, M; Takagui, E M; Taketani, A; Tamai, M; Tanaka, K H; Tanaka, Y; Taniguchi, E; Tannenbaum, M J; Thomas, J; Thomas, J H; Thomas, T L; Tian, W; Tojo, J; Torii, H A; Towell, R S; Tserruya, Itzhak; Tsuruoka, H; Tsvetkov, A A; Tuli, S K; Tydesjo, H; Tyurin, N; Ushiroda, T; van Hecke, H; Velissaris, C; Velkovska, J; Velkovsky, M; Vinogradov, A A; Volkov, M A; Vorobyov, A A; Vznuzdaev, E A; Wang, H; Watanabe, Y; White, S N; Witzig, C; Wohn, F K; Woody, C L; Xie, W; Yagi, K; Yokkaichi, S; Young, G R; Yushmanov, I E; Zajc, W A; Zhang, Z; Zhou, S

    2004-01-01

    Extensive experimental data from high-energy nucleus-nucleus collisions were recorded using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The comprehensive set of measurements from the first three years of RHIC operation includes charged particle multiplicities, transverse energy, yield ratios and spectra of identified hadrons in a wide range of transverse momenta (p_T), elliptic flow, two-particle correlations, non-statistical fluctuations, and suppression of particle production at high p_T. The results are examined with an emphasis on implications for the formation of a new state of dense matter. We find that the state of matter created at RHIC cannot be described in terms of ordinary color neutral hadrons.

  16. {pi}{pi}-correlations in hot and dense matter; {pi}{pi}-Korrelationen in heisser und dichter Materie

    Energy Technology Data Exchange (ETDEWEB)

    Isselhorst, C.

    2006-07-01

    Properties of the {pi}{pi}-interactions in hot and dense matter are studied within a nonperturbative and symmetry conserving approach. The pion and its chiral partner, the {sigma}-meson, are described within the linear {sigma} model and special attention is given to the conservation of the underlying chiral symmetry. The first part deals with the properties of pion and {sigma} in the vacuum, the further being the ''Goldstone''-boson of the theory, while the latter is a broad resonance. The results in the vacuum are tested against experimental results like {pi}{pi}-phase shifts as well as the mass and the width of the {sigma}-meson. Besides the propagator of the {sigma}-meson, the preservation of the chiral symmetry is explicitly examined and chiral Ward identities for the n-point functions of the theory are fulfilled. Furthermore the {pi}{pi}-scattering matrix is calculated and shown to be consistent with predictions from chiral perturbation theory. In the second part of this work the model is extended to finite temperature with special emphasis on the chiral phase transition. The transition temperature and the critical exponent {beta} are determined, and the influence of the temperature on the propagator of the s-meson as well as on the {pi}{pi}-scattering matrix is examined. The third part deals with the properties of pion and {sigma} in dense matter. Additional couplings like the ones to particle-hole excitations and short range repulsion have to be included to ensure stability at nuclear matter density. At zero three momentum one observes a strong downward shift of the {sigma}-mass accompanied by an accumulation of strength near the two-pion threshhold in the spectral function. Taking into account a finite three momentum for the {pi}{pi}-pair, respectively the {sigma}-meson, one observes a weakening of the aforementioned effect. Having thus developed a model for the {pi}{pi}-interaction at finite temperature and density, we try to describe

  17. Equation of state constraints for the cold dense matter inside neutron stars using the cooling tail method

    CERN Document Server

    Nättilä, J; Kajava, J J E; Suleimanov, V F; Poutanen, J

    2015-01-01

    The cooling phase of thermonuclear (type-I) X-ray bursts can be used to constrain the neutron star (NS) compactness by comparing the observed cooling tracks of bursts to accurate theoretical atmosphere model calculations. By applying the so-called cooling tail method, where the information from the whole cooling track is used, we constrain the mass, radius, and distance for three different NSs in low-mass X-ray binaries 4U 1702-429, 4U 1724-307, and SAX J1810.8-260. Care is taken to only use the hard state bursts where it is thought that only the NS surface alone is emitting. We then utilize a Markov chain Monte Carlo algorithm within a Bayesian framework to obtain a parameterized equation of state (EoS) of cold dense matter from our initial mass and radius constraints. This allows us to set limits on various nuclear parameters and to constrain an empirical pressure-density relation for the dense matter. Our predicted EoS results in NS radius between 10.5-12.8 km (95% confidence limits) for a mass of 1.4 $M_{...

  18. Athena's Constraints on the Dense Matter Equation of State from Quiescent Low Mass X-ray Binaries

    Science.gov (United States)

    Guillot, Sebastien

    2016-07-01

    The study of neutron star quiescent low-mass X-ray binaries (qLMXBs) will address one of the science goals of the Athena X-ray observatory. The study of the soft X-ray thermal emission from the neutron star surface in qLMXBs is a crucial tool to place constrains on the dense matter equation of state and understand the interior structure of neutron stars. I will briefly review this method, its strengths and current weaknesses and limitations, as well as the current constraints on the equation of state from qLMXBs. The superior sensitivity of Athena will permit the acquisition of unprecedentedly high signal-to-noise spectra from these sources. It has been demonstrated that a single qLMXB, even with a high signal-to-noise spectrum, will not place useful constraints on the dense matter equation of state. However, a combination of qLMXB spectra has shown great promises of obtaining tight constraints on the equation of state. I will discuss the expected prospects for observations of qLMXBs and in particular, I will show that very tight constraints on the equation of state can be obtained from the observations of qLMXBs with the Athena X-ray observatory (even with a 10 % uncertainty on the flux calibration).

  19. Pair potentials for warm dense matter and their application to x-ray Thomson scattering in aluminum and beryllium

    Science.gov (United States)

    Harbour, L.; Dharma-wardana, M. W. C.; Klug, D. D.; Lewis, L. J.

    2016-11-01

    Ultrafast laser experiments yield increasingly reliable data on warm dense matter, but their interpretation requires theoretical models. We employ an efficient density functional neutral-pseudoatom hypernetted-chain (NPA-HNC) model with accuracy comparable to ab initio simulations and which provides first-principles pseudopotentials and pair potentials for warm-dense matter. It avoids the use of (i) ad hoc core-repulsion models and (ii) "Yukawa screening" and (iii) need not assume ion-electron thermal equilibrium. Computations of the x-ray Thomson scattering (XRTS) spectra of aluminum and beryllium are compared with recent experiments and with density-functional-theory molecular-dynamics (DFT-MD) simulations. The NPA-HNC structure factors, compressibilities, phonons, and conductivities agree closely with DFT-MD results, while Yukawa screening gives misleading results. The analysis of the XRTS data for two of the experiments, using two-temperature quasi-equilibrium models, is supported by calculations of their temperature relaxation times.

  20. Enhancing the light-matter interaction using slow light: towards the concept of dense light

    OpenAIRE

    Thévenaz, Luc; Dicaire, Isabelle; Chin, Sang Hoon

    2012-01-01

    A couple of experiments are here presented to clarify the impact of slow light on light-matter interaction. The experiments are designed, so that the process generating slow light and the probed light-matter interaction only present a marginal cross-effect. The impact of slow light on simple molecular absorption could be separately evaluated under either material or structural slow light propagation in the same medium and led to an entirely different response.

  1. Hadronic and Quark-Gluon Excitations of Dense and Hot Matter

    CERN Document Server

    Renk, T; Weise, W

    2002-01-01

    We summarize recent developments in our understanding of low-mass quark-antiquark excitations in hadronic matter under various different conditions. This includes the thermodynamics of the chiral condensate, pions as Goldstone bosons in normal nuclear matter, and excursions into extreme territory of the QCD phase diagram: lepton pair production from a fireball expanding through the transition boundary between the quark-gluon and hadron pha ses of QCD.

  2. The impact of three dimensional MHD instabilities on the generation of warm dense matter using a MA-class linear transformer driver

    Science.gov (United States)

    Gourdain, P.-A.; Seyler, C. E.

    2017-09-01

    Warm dense matter is difficult to generate since it corresponds to a state of matter which pressure is order of magnitude larger than can be handled by natural materials. A diamond anvil can be used to pressurize matter up to one Gbar, this matter is at high density but at room temperature. High power lasers and heavy ion beams can generate warm dense matter on time scales where measuring quasi-static transport coefficients such as viscosity or heat conduction proves difficult since both experimental techniques relies on inertial confinement. We present here a third method to generate warm dense matter. It uses a pulsed-power driver which current rise time is substantially shortened by using a plasma opening switch, limiting the development of electrothermal instabilities. The switch relies on the implosion of a gas puff Z-pinch which carries most of the discharge current until the pinch reaches the sample. After that, the sample is compressed until it reaches the warm dense matter regime. Three-dimensional magnetohydrodynamics computations show that if the density of the gas is low enough no detectable instabilities (e.g. kinks and sausages modes) impede the remainder of the implosion.

  3. Constraining the WDM Particle Mass with Milky Way Satellites

    CERN Document Server

    Kennedy, Rachel; Cole, Shaun; Benson, Andrew

    2013-01-01

    Well-motivated particle physics theories predict the existence of particles (such as sterile neutrinos) which acquire non-negligible thermal velocities in the early universe. These particles could behave as warm dark matter (WDM) and generate a small-scale cutoff in the linear density power spectrum which scales approximately inversely with the particle mass. If this mass is of order a keV, the cutoff occurs on the scale of dwarf galaxies. Thus, in WDM models the abundance of small galaxies, such as the satellites that orbit in the halo of the Milky Way, depends on the mass of the warm particle. The abundance also scales with the mass of the host galactic halo. We use the \\galform semi-analytic model of galaxy formation to calculate the properties of galaxies in universes in which the dark matter is warm. Using this method, we can compare the predicted satellite luminosity functions to the observed data for the Milky Way dwarf spheroidals, and determine a lower bound on the thermally produced WDM particle mas...

  4. Visualizing expanding warm dense matter heated by laser-generated ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Woosuk [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-24

    This PowerPoint presentation concluded with the following. We calculated the expected heating per atom and temperatures of various target materials using a Monte Carlo simulation code and SESAME EOS tables. We used aluminum ion beams to heat gold and diamond uniformly and isochorically. A streak camera imaged the expansion of warm dense gold (5.5 eV) and diamond (1.7 eV). GXI-X recorded all 16 x-ray images of the unheated gold bar targets proving that it could image the motion of the gold/diamond interface of the proposed target.

  5. Equation of State of Dense Matter and Consequences for Neutron Stars

    Directory of Open Access Journals (Sweden)

    Thomas A. W.

    2013-12-01

    Full Text Available There is currently tremendous interest in the role of hyperons and other exotic forms of matter in neutron stars. This is particularly so following the measurement by Demorest et al. of a star with a mass almost 2 solar masses. Given that we know of no physical mechanism to stop the occurrence of hyperons at matter in beta–equilibrium above roughly 3 times nuclear matter density, we discuss the constraints on the possible maximum mass when hyperons are included in the equation of state. The discussion includes a careful assessment of the constraints from low energy nuclear properties as well as the properties of hypernuclei. The model within which these calculations are carried out is the quark-meson coupling (QMC model, which is derived starting at the quark level.

  6. Spin polarization phenomena in dense neutron matter at a strong magnetic field

    CERN Document Server

    Isayev, A A

    2010-01-01

    Spin polarized states in neutron matter at strong magnetic fields up to $10^{18}$ G are considered in the model with the Skyrme effective interaction. Analyzing the self-consistent equations at zero temperature, it is shown that a thermodynamically stable branch of solutions for the spin polarization parameter as a function of density corresponds to the negative spin polarization when the majority of neutron spins are oriented oppositely to the direction of the magnetic field. Besides, it is found that in a strong magnetic field the state with the positive spin polarization can be realized as a metastable state at the high density region in neutron matter. At finite temperature, the entropy of the thermodynamically stable branch demonstrates the unusual behavior being larger than that for the nonpolarized state (at vanishing magnetic field) above certain critical density which is caused by the dependence of the entropy on the effective masses of neutrons in a spin polarized state.

  7. On the definition of Burnett transport coefficients of the dense multi-element charged matter

    CERN Document Server

    Pavlov, G A

    2003-01-01

    To determine the Burnett transport coefficients of non-ideal multi-element charged matter the representations of conservation equations of matter as generalized Langevin equations are used. Mori's algorithm is revised to derive the equation of motion of a dynamical value operator of a system in the form of the generalized nonlinear Langevin equation. After transformation, using necessary variational derivatives, these equations are compared with the Burnett hydrodynamical conservation equations. In consequence, the response function expressions of transport coefficients corresponding to second-order derivatives of thermal disturbances are found in the long-wavelength and low-frequency limits. To establish a link between the results of the executed investigations and hydrodynamical problems the properties of the high derivative coefficients matrix of the set of conservation equations in the linearized Burnett approximation are discussed.

  8. Nucleon-nucleon effective potential in dense matter including rho-meson exchange

    CERN Document Server

    Mornas, L; Pérez, A

    2002-01-01

    We obtain the RPA summed one-meson exchange potential between nucleons in symmetric nuclear matter at zero temperature, from a model which includes rho, sigma, omega and pi mesons. The behavior of rho mesons inside the medium is first discussed using different schemes to extract a finite contribution from the vacuum polarization. These schemes give qualitatively different results for the in-medium rho mass. The results are discussed in connection with the nonrenormalizability of the model. We next study the modified potential as density increases. In the intermediate-distance range, it is qualitatively modified by matter and vacuum effects. In the long-distance range (r>2 fm), one observes the presence of oscillations, which are not present in free space. Features on this distance range are insensitive to the renormalization scheme.

  9. Kondo cloud of single heavy quark in cold and dense matter

    CERN Document Server

    Yasui, Shigehiro

    2016-01-01

    The Kondo effect is a universal phenomena observed in a variety of fermion systems containing a heavy impurity particle whose interaction is governed by the non-Abelian interaction. At extremely high density, I study the Kondo effect by color exchange in quark matter containing a single heavy (charm or bottom) quark as an impurity particle. To obtain the ground state with the Kondo effect, I introduce the condensate mixing the light quark and the heavy quark (Kondo cloud) in the mean-field approximation. I estimate the energy gain by formation of the Kondo cloud, and present that the Kondo cloud exhibits the resonant structure. I also evaluate the scattering cross section for the light quark and the heavy quark, and discuss its effect to the finite size quark matter.

  10. Kondo cloud of single heavy quark in cold and dense matter

    Science.gov (United States)

    Yasui, Shigehiro

    2017-10-01

    The Kondo effect is a universal phenomena observed in a variety of fermion systems containing a heavy impurity particle whose interaction is governed by the non-Abelian interaction. At extremely high density, I study the Kondo effect by color exchange in quark matter containing a single heavy (charm or bottom) quark as an impurity particle. To obtain the ground state with the Kondo effect, I introduce the condensate mixing the light quark and the heavy quark (Kondo cloud) in the mean-field approximation. I estimate the energy gain by formation of the Kondo cloud, and present that the Kondo cloud exhibits the resonant structure. I also evaluate the scattering cross section for the light quark and the heavy quark, and discuss its effect to the finite size quark matter.

  11. (In)stability in dense strange hadronic matter and compact stars

    CERN Document Server

    Torres, James R; Menezes, Debora P

    2016-01-01

    Background : The emergence of hyperon degrees of freedom in neutron star matter has been associated to first order phase transitions in some phenomenological models, but conclusions on the possible physical existence of an instability in the strangeness sector are strongly model dependent. Purpose : The purpose of the present study is to assess whether strangeness instabilities are related to specific values of the largely unconstrained hyperon interactions, and to study the effect of the strange meson couplings on phenomenological properties of neutron stars and supernova matter, once these latter are fixed to fulfill the constraints imposed by hypernuclear data. Method : We consider a phenomenological RMF model sufficiently simple to allow a complete exploration of the parameter space. Results : We show that no instability at supersaturation density exists for the RMF model, as long as the parameter space is constrained by basic physical requirements. This is at variance with a non-relativistic functional, ...

  12. From non-degenerate conducting polymers to dense matter in the massive Gross-Neveu model

    CERN Document Server

    Thies, M; Thies, Michael; Urlichs, Konrad

    2005-01-01

    Using results from the theory of non-degenerate conducting polymers like cis-polyacetylene, we generalize our previous work on baryonic matter in the massless Gross-Neveu model to finite bare fermion mass. In the large N limit, the exact ground state is constructed analytically, in close analogy to the bipolaron lattice in polymers. These findings are contrasted to the standard scenario with a first order phase transition as a function of density.

  13. Monte-Carlo approach to calculate the ionization of warm dense matter within particle-in-cell simulations

    CERN Document Server

    Wu, D; Yu, W; Fritzsche, S

    2016-01-01

    A physical model based on Monte-Carlo approach is proposed to calculate the ionization dynamics of warm dense matters within particle-in-cell simulations, where impact ionization, electron-ion recombination and ionization potential depression (IPD) by surrounding plasmas are taken into consideration self-consistently. When compared with other models, which are applied in the literature for plasmas near thermal equilibrium, the temporal relaxation of ionizations can also be simulated by the proposed model with the final thermal equilibrium determined by the competition between impact ionization and its inverse process, i.e., electron-ion recombination. Our model is general and can be applied for both single elements and alloys with quite different compositions. The proposed model is implemented into a particle-in-cell (PIC) simulation code, and the average ionization degree of bulk aluminium varying with temperature is calculated, showing good agreement with the data provided by FLYCHK code.

  14. Very low electron temperature in warm dense matter formed by focused picosecond soft x-ray laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Ishino, Masahiko, E-mail: ishino.masahiko@jaea.go.jp; Hasegawa, Noboru; Nishikino, Masaharu; Kawachi, Tetsuya; Yamagiwa, Mitsuru [Quantum Beam Science Center, Japan Atomic Energy Agency, 8-1-7, Umemidai, Kizugawa, Kyoto 619-0215 (Japan); Pikuz, Tatiana [Joint Institute for High Temperatures, Russian Academy of Sciences, 13-2, Izhorskaya Street, Moscow 125412 (Russian Federation); Graduate School of Engineering, Osaka University, 1-1, Yamadaoka, Suita, Osaka 565-0871 (Japan); Skobelev, Igor [Joint Institute for High Temperatures, Russian Academy of Sciences, 13-2, Izhorskaya Street, Moscow 125412 (Russian Federation); National Research Nuclear University, Moscow Engineering Physics Institute, 31, Kashirskoe Shosse, Moscow 115409 (Russian Federation); Faenov, Anatoly [Joint Institute for High Temperatures, Russian Academy of Sciences, 13-2, Izhorskaya Street, Moscow 125412 (Russian Federation); Institute for Academic Initiatives, Osaka University, 1-1, Yamadaoka, Suita, Osaka 565-0871 (Japan); Inogamov, Nail [Landau Institute for Theoretical Physics, Russian Academy of Sciences, 1-A, Akademika Semenova av., Chernogolovka, Moscow Region 142432 (Russian Federation)

    2014-11-14

    We investigated the optical emission from the ablating surfaces induced by the irradiations of soft x-ray laser (SXRL) pulses with the aim of estimation of the maximum electron temperature. No emission signal in the spectral range of 400–800 nm could be observed despite the formation of damage structures on the target surfaces. Hence, we estimated an upper limit for the electron temperature of 0.4–0.7 eV for the process duration of 100–1000 ps. Our results imply that the ablation and/or surface modification by the SXRL is not accompanied by plasma formation but is induced by thermo-mechanical pressure, which is so called a spallative ablation. This spallative ablation process occurs in the low electron temperature region of a non-equilibrium state of warm dense matter.

  15. Theory of complex fluids in the warm-dense-matter regime, and application to phase-transitions in liquid carbon

    CERN Document Server

    Dharma-wardana, M W C

    2016-01-01

    Using data from recent laser-shock experiments and related density-functional molecular-dynamics simulations on carbon, we demonstrate that the ionic structures predicted within the neutral-pseudo-atom approach for a complex liquid in the warm-dense matter regime are in good agreement with available data, even where transient covalent bonding dominates ionic correlations. Evidence for an unusual phase transition of a liquid $\\to$ vapor with an abrupt decrease in ionization occurring simultaneously is presented. Here a covalently-bonded metallic-liquid, i.e., carbon of density 1.0 g/cm$^3$, transits to a disordered mono-atomic fluid at 7 eV. Other transitions where the mean ionization $Z$ drops abruptly are also uncovered

  16. Exotic dense matter states pumped by relativistic laser plasma in the radiation dominant regime

    CERN Document Server

    Colgan, J; Jr.,; Faenov, A Ya; Pikuz, S A; Wagenaars, E; Booth, N; Brown, C R D; Culfa, O; Dance, R J; Evans, R G; Gray, R J; Hoarty, D J; Kaempfer, T; Lancaster, K L; McKenna, P; Rossall, A L; Skobelev, I Yu; Schulze, K S; Uschmann, I; Zhidkov, A G; Woolsey, N C

    2012-01-01

    The properties of high energy density plasma are under increasing scrutiny in recent years due to their importance to our understanding of stellar interiors, the cores of giant planets$^{1}$, and the properties of hot plasma in inertial confinement fusion devices$^2$. When matter is heated by X-rays, electrons in the inner shells are ionized before the valence electrons. Ionization from the inside out creates atoms or ions with empty internal electron shells, which are known as hollow atoms (or ions)$^{3,4,5}$. Recent advances in free-electron laser (FEL) technology$^{6,7,8,9}$ have made possible the creation of condensed matter consisting predominantly of hollow atoms. In this Letter, we demonstrate that such exotic states of matter, which are very far from equilibrium, can also be formed by more conventional optical laser technology when the laser intensity approaches the radiation dominant regime$^{10}$. Such photon-dominated systems are relevant to studies of photoionized plasmas found in active galactic ...

  17. Approach to the propagation of massive neutrinos in dense matter by Wigner functions

    Science.gov (United States)

    Sirera Tomas, Miguel

    The problem of massive neutrinos comes from Grant Unification Theories but also from the so called Neutrino Solar Puzzle. The solution of this puzzle seems to be in the neutrinos physics and to need that the neutrinos are particles with mass. The possible mass of the neutrinos is not only important for Solar Neutrinos but also in other astrophysical environments such as Supernovae, Neutron Stars or The Early Universe. If the neutrinos are particles with mass, or at least one of their generations, oscillations are produced in both vacuum and matter. The oscillation in matter could cause the so called MSW effect, that transforms a neutrino flavour to another. The problem of the propagation of neutrinos in matter has been dealt with by many authors who have usually solved the covariant motion equations, and sometimes by Green Functions. In this work, this has been done using statistical techniques by Wigner Functions, which do not only allow us to study the propagation ways but also to know the behavior of the neutrinos field in equilibrium. On the other hand, the astrophysical systems, that we have commented above, yield a great amount of neutrinos which spread through them and are finally emitted to space, and so it is important to have a transport equation that explain how a neutrinos distribution is spread which is not in equilibrium. It is possible to achieve this equation by motion equations of the Wigner Functions.

  18. Probing properties of hot and dense QCD matter with heavy flavor in the PHENIX experiment at RHIC

    Directory of Open Access Journals (Sweden)

    Nouicer Rachid

    2015-01-01

    Full Text Available Hadrons carrying heavy quarks, i.e. charm or bottom, are important probes of the hot and dense medium created in relativistic heavy ion collisions. Heavy quarkantiquark pairs are mainly produced in initial hard scattering processes of partons. While some of the produced pairs form bound quarkonia, the vast majority hadronize into particles carrying open heavy flavor. Heavy quark production has been studied by the PHENIX experiment at RHIC via measurements of single leptons from semi-leptonic decays in both the electron channel at mid-rapidity and in the muon channel at forward rapidity. A large suppression and azimuthal anisotropy of single electrons have been observed in Au + Au collisions at 200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. The PHENIX experiment has also measured J/ψ production at 200 GeV in p + p, d + Au, Cu + Cu and Au + Au collisions, both at mid- and forward-rapidities, and additionally Cu + Au and U + U at forward-rapidities. In the most energetic collisions, more suppression is observed at forward rapidity than at central rapidity. This can be interpreted either as a sign of quark recombination, or as a hint of additional cold nuclear matter effects. The centrality dependence of nuclear modification factor, RAA(pT, for J/ψ in U + U collisions at √sNN = 193 GeV shows a similar trend to the lighter systems, Au + Au and Cu + Cu, at similar energy 200 GeV.

  19. Ultrafast Hierarchical OTDM/WDM Network

    Directory of Open Access Journals (Sweden)

    Hideyuki Sotobayashi

    2003-12-01

    Full Text Available Ultrafast hierarchical OTDM/WDM network is proposed for the future core-network. We review its enabling technologies: C- and L-wavelength-band generation, OTDM-WDM mutual multiplexing format conversions, and ultrafast OTDM wavelengthband conversions.

  20. Neutral current interactions of low-energy neutrinos in dense neutron matter

    CERN Document Server

    Lovato, Alessandro; Gandolfi, Stefano; Losa, Cristina

    2013-01-01

    We report the results of a calculation of the response of cold neutron matter to neutral-current interactions with low energy neutrinos, carried out using an effective interaction and effective operators consistently derived within the formalism of Correlated Basis Functions. The neutrino mean free path obtained from the calculated responses turns out to be strongly affected by both short and long range correlations, leading to a sizable increase with respect to the prediction of the Fermi gas model. The consistency between the proposed approach and Landau theory of normal Fermi liquids also has been investigated, using a set of Landau parameters obtained from the matrix elements of the effective interaction.

  1. Zero Sound in Neutron Stars with Dense Quark Matter under Strong Magnetic Fields

    CERN Document Server

    Kouvaris, Chris

    2009-01-01

    We study a neutron star with a quark matter core under extremely strong magnetic fields. We investigate the possibility of an Urca process as a mechanism for the cooling of such a star. We found that apart from very particular cases, the Urca process cannot occur. We also study the stability of zero sound modes under the same conditions. We derive limits for the coupling constant of an effective theory, in order the zero sound to be undamped. We show that zero sound modes can help kinematically to facilitate a cooling process.

  2. Vector mesons in dense matter and dilepton production in heavy ion collisions at intermediate energies

    Energy Technology Data Exchange (ETDEWEB)

    Santini, Elvira

    2008-02-15

    The vector meson spectral functions are calculated to the first order in the nuclear matter density assuming the dominant contribution comes from the couplings of the vector mesons to nucleons and nucleon resonances. An attempt is made to reproduce the HADES dilepton production data with the in-medium spectral functions of the vector mesons using the Relativistic Quantum Molecular Dynamics (RQMD) transport model developed earlier for modelling heavy-ion collisions. The results are sensitive to the in-medium broadening of nucleon resonances. A generally good agreement with the HADES data is achieved for selfconsistent treatment of the nucleon resonance broadening and the vector meson spectral functions. (orig.)

  3. Dissipative properties of hot and dense hadronic matter in excluded volume hadron resonance gas model

    CERN Document Server

    Kadam, Guru Prakash

    2015-01-01

    We estimate dissipative properties viz: shear and bulk viscosities of hadronic matter using rel- ativistic Boltzmann equation in relaxation time approximation within ambit of excluded volume hadron resonance gas (EHRG) model. We find that at zero baryon chemical potential the shear viscosity to entropy ratio ({\\eta}/s) decreases with temperature and reaches very close to Kovtun-Son- Starinets (KSS) bound. At sufficiently large baryon chemical potential this ratio shows same behav- ior as a function of temperature but goes below KSS bound. We further find that along chemical freezout line {\\eta}/s increases monotonically while the bulk viscosity to entropy ratio ({\\zeta}/s) decreases monotonically.

  4. Critical temperatures for superconducting quark matter existence in dense stellar cores

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, J.E. (Inst. Astronomico e Geofisico, Univ. de Sao Paulo, Av. M. Stefano 4200 (04301) Sao Paulo (BR)); Benvenuto, O.G. (Facultad de Ciencias Astronomicas y Geofisicas UNLP, Paseo del Bosque S/N (1900) La Plata (AR)); Vucetich, H. (Dept. di Fisica UNLP, Calle 49 y 115, C.C. 65, (1900) La Plata (AR))

    1992-04-10

    If quark matter is actually a component of compact stars it can probably develop a superconducting phase as a result of QCD interactions. This effect may be harmless for (or dramatically affect) the properties of the star, depending on the actual value of the strong coupling constant {alpha}{sub c}. Explicit expressions for the critical temperature T{sub c} are derived by using some recent results on the long-range behavior of the gluon propagators. In this paper the consequences for the cooling histories of compact stars and possible trends are briefly discussed.

  5. Heavy quarkonium moving in a hot and dense deconfined nuclear matter

    CERN Document Server

    Thakur, Lata; Mishra, Hiranmaya

    2016-01-01

    We study the behavior of the complex potential between a heavy quark and its anti-quark, which are in relative motion with respect to a hot and dense medium. The heavy quark-antiquark complex potential is obtained by correcting both the Coulombic and the linear terms in the Cornell potential through a dielectric function estimated within real-time formalism using the hard thermal loop (HTL) approximation. We show the variation of both the real and the imaginary parts of the potential for different values of velocities when the bound state ($ Q\\bar{Q}$ pair) is aligned in the direction parallel as well as perpendicular to the relative velocity of the $ Q\\bar{Q}$ pair with thermal medium. With increase of the relative velocity the screening of the real part of potential becomes weaker at short distances and stronger at large distances for the parallel case. However, for the perpendicular case, the potential decreases with increase in velocity at all the distances which results in the larger screening of the pot...

  6. Viscosity and equation of state of hot and dense QCD matter - ARRA portion

    Energy Technology Data Exchange (ETDEWEB)

    Molnar, Denes [Purdue Univ., West Lafayette, IN (United States)

    2014-04-14

    The Section below summarizes research activities and achievements during the first four years of the PI’s Early Career Research Project (ECRP). Two main areas have been advanced: i) radiative 3 ↔ 2 radiative transport, via development of a new computer code MPC/Grid that solves the Boltzmann transport equation in full 6+1D (3X+3V+time) on both single-CPU and parallel computers; ii) development of a self-consistent framework to convert viscous fluids to particles, and application of this framework to relativistic heavy-ion collisions, in particular, determination of the shear viscosity. Year 5 of the ECRP is under a separate award number, and therefore it has its own report document ’Final Technical Report for Year 5 of the Early Career Research Project “Viscosity and equation of state of hot and dense QCDmatter”’ (award DE-SC0008028). The PI’s group was also part of the DOE JET Topical Collaboration, a multi-institution project that overlapped in time significantly with the ECRP. Purdue achievements as part of the JET Topical Collaboration are in a separate report “Final Technical Report summarizing Purdue research activities as part of the DOE JET Topical Collaboration” (award DE-SC0004077).

  7. $^3P_2$-$^3F_2$ Pairing in Dense Neutron Matter The Spectrum of Solutions

    CERN Document Server

    Zverev, M V; Khodel, V A

    2003-01-01

    The $^3P_2$-$^3F_2$ pairing model is generally considered to provide an adequate description of the superfluid states of neutron matter at densities some 2-3 times that of saturated symmetrical nuclear matter. The problem of solving the system of BCS gap equations expressing the $^3P_2$-$^3F_2$ model is attacked with the aid of the separation approach. This method, developed originally for quantitative study of S-wave pairing in the presence of strong short-range repulsions, serves effectively to reduce the coupled, singular, nonlinear BCS integral equations to a set of coupled algebraic equations. For the first time, sufficient precision becomes accessible to resolve small energy splittings between the different pairing states. Adopting a perturbative strategy, we are able to identify and characterize the full repertoire of real solutions of the $^3P_2$-$^3F_2$ pairing model, in the limiting regime of small tensor-coupling strength. The P-F channel coupling is seen to lift the striking parametric degeneracie...

  8. Equation of state of dense matter and the minimum mass of cold neutron stars

    CERN Document Server

    Haensel, P; Douchin, F

    2002-01-01

    Equilibrium configurations of cold neutron stars near the minimum mass are studied, using the recent equation of state SLy, which describes in a unified, physically consistent manner, both the solid crust and the liquid core of neutron stars. Results are compared with those obtained using an older FPS equation of state of cold catalyzed matter. The value of M_min\\simeq 0.09M_sun depends very weakly on the equation of state of cold catalyzed matter: it is 0.094 M_sun for the SLy model, and 0.088 M_sun for the FPS one. Central density at M_min is significantly lower than the normal nuclear density: for the SLy equation of state we get central density 1.7 10^{14} g/cm^3, to be compared with 2.3 10^{14} g/cm^3 obtained for the FPS one. Even at M_min, neutron stars have a small liquid core of radius of about 4 km, containing some 2-3% of the stellar mass. Neutron stars with 0.09 M_sun

  9. An effective theory for jet propagation in dense QCD matter: jet broadening and medium-induced bremsstrahlung

    CERN Document Server

    Ovanesyan, Grigory

    2011-01-01

    Two effects, jet broadening and gluon bremsstrahlung induced by the propagation of a highly energetic quark in dense QCD matter, are reconsidered from effective theory point of view. We modify the standard Soft Collinear Effective Theory (SCET) Lagrangian to include Glauber modes, which are needed to implement the interactions between the medium and the collinear fields. We derive the Feynman rules for this Lagrangian and show that it is invariant under soft and collinear gauge transformations. We find that the newly constructed theory SCET$_{\\rm G}$ recovers exactly the general result for the transverse momentum broadening of jets. In the limit where the radiated gluons are significantly less energetic than the parent quark, we obtain a jet energy-loss kernel identical to the one discussed in the reaction operator approach to parton propagation in matter. In the framework of SCET$_{\\rm G}$ we present results for the fully-differential bremsstrahlung spectrum for both the incoherent and the Landau-Pomeranchun...

  10. Monte-Carlo approach to calculate the proton stopping in warm dense matter within particle-in-cell simulations

    CERN Document Server

    Wu, D; Yu, W; Fritzsche, S

    2016-01-01

    A Monte-Carlo approach to proton stopping in warm dense matter is implemented into an existing particle-in-cell code. The model is based on multiple binary-collisions among electron-electron, electron-ion and ion-ion, taking into account contributions from both free and bound electrons, and allows to calculate particle stopping in much more natural manner. At low temperature limit, when ``all'' electron are bounded at the nucleus, the stopping power converges to the predictions of Bethe-Bloch theory, which shows good consistency with data provided by the NIST. With the rising of temperatures, more and more bound electron are ionized, thus giving rise to an increased stopping power to cold matter, which is consistent with the report of a recently experimental measurement [Phys. Rev. Lett. 114, 215002 (2015)]. When temperature is further increased, with ionizations reaching the maximum, lowered stopping power is observed, which is due to the suppression of collision frequency between projected proton beam and h...

  11. The role of gauge fields in cold and dense quark matter

    Energy Technology Data Exchange (ETDEWEB)

    Noronha, J.

    2007-07-01

    In this thesis we investigate the role played by gauge fields in providing new observable signatures that can attest to the presence of color superconductivity in neutron stars. We show that thermal gluon fluctuations in color-flavor locked superconductors can substantially increase their critical temperature and also change the order of the transition, which becomes a strong first-order phase transition. Moreover, we explore the effects of strong magnetic fields on the properties of color-flavor locked superconducting matter. We find that both the energy gaps as well as the magnetization are oscillating functions of the magnetic field. Also, it is shown that the magnetization can be so strong that homogeneous quark matter becomes metastable for a range of parameters. This points towards the existence of magnetic domains or other types of magnetic inhomogeneities in the hypothesized quark cores of magnetars. Obviously, our results only apply if the strong magnetic fields observed on the surface of magnetars can be transmitted to their inner core. This can occur if the superconducting protons expected to exist in the outer core form a type-II superconductor. However, it has been argued that the observed long periodic oscillations in isolated pulsars can only be explained if the outer core is a type-I superconductor rather than type-II. We show that this is not the only solution for the precession puzzle by demonstrating that the long-term variation in the spin of PSR 1828-11 can be explained in terms of Tkachenko oscillations within superfluid shells. (orig.)

  12. Heavy vector and axial-vector mesons in hot and dense asymmetric strange hadronic matter

    Science.gov (United States)

    Kumar, Arvind; Chhabra, Rahul

    2015-09-01

    We calculate the effects of finite density and temperature of isospin asymmetric strange hadronic matter, for different strangeness fractions, on the in-medium properties of vector (D*,Ds*,B*,Bs*) and axial-vector (D1,D1 s,B1,B1 s) mesons, using the chiral hadronic SU(3) model and QCD sum rules. We focus on the evaluation of in-medium mass-shift and shift in decay constant of above vector and axial-vector mesons. In the quantum chromodynamics sum rule approach, the properties, e.g., the masses and decay constants of vector and axial-vector mesons are written in terms of quark and gluon condensates. These quark and gluon condensates are evaluated in the present work within the chiral SU(3) model, through the medium modification of scalar-isoscalar fields σ and ζ , the scalar-isovector field δ , and the scalar dilaton field χ , in the strange hadronic medium which includes both nucleons as well as hyperons. As we shall see in detail, the masses and decay constants of heavy vector and axial-vector mesons are affected significantly from isospin asymmetry and the strangeness fraction of the medium, and these modifications may influence the experimental observables produced in heavy-ion collision experiments. The results of present investigations of in-medium properties of vector and axial-vector mesons at finite density and temperature of strange hadronic medium may be helpful for understanding the experimental data from heavy-ion collision experiments in particular for the compressed baryonic matter (CBM) experiment of the FAIR facility at GSI, Germany.

  13. Constraining the Bulk Properties of Dense Matter by Measuring Millisecond Pulsar Masses - A White Paper for the Astronomy and Astrophysics Decadal Survey, CFP Panel

    CERN Document Server

    Freire, Paulo C; Lattimer, James; Stairs, Ingrid; Arzoumanian, Zaven; Cordes, James; Deneva, Julia

    2009-01-01

    More than four decades after the discovery of pulsars, the composition of matter at their cores is still a mystery. This white paper summarizes how recent high-precision measurements of millisecond pulsar masses have introduced new experimental constraints on the properties of super-dense matter, and how continued timing of intriguing new objects, coupled with radio telescope surveys to discover more pulsars, might introduce significantly more stringent constraints.

  14. Viscosity and equation of state of hot and dense QCD matter

    Energy Technology Data Exchange (ETDEWEB)

    Molnar, Denes [Purdue Univ., West Lafayette, IN (United States)

    2016-05-25

    The Section below summarizes research activities and achievements during the fifth (last) year of the PI’s Early Career Research Project (ECRP). Unlike the first four years of the project, the last year was not funded under the American Recovery and Reinvestment Act (ARRA). The ECRP advanced two main areas: i) radiative 3 ↔ 2 radiative transport, via development of a new computer code MPC/Grid that solves the Boltzmann transport equation in full 6+1D (3X+3V+time); and ii) application of relativistic hydrodynamics, via development of a self-consistent framework to convert viscous fluids to particles. In Year 5 we finalized thermalization studies with radiative gg ↔ ggg transport (Sec. 1.1.1) and used nonlinear covariant transport to assess the accuracy of fluid-to-particle conversion models (Sec. 1.1.2), calculated observables with self-consistent fluid-to- particle conversion from realistic viscous hydrodynamic evolution (Secs. 1.2.1 and 1.2.2), extended the covariant energy loss formulation to heavy quarks (Sec. 1.4.1) and studied energy loss in small systems (Sec. 1.4.2), and also investigated how much of the elliptic flow could have non- hydrodynamic origin (Sec 1.3). Years 1-4 of the ECRP were ARRA-funded and, therefore, they have their own report document ’Final Technical Report for Years 1-4 of the Early Career Research Project “Viscosity and equation of state of hot and dense QCD matter”’ (same award number DE-SC0004035). The PI’s group was also part of the DOE JET Topical Collaboration, a multi-institution project that overlapped in time significantly with the ECRP. Purdue achievements as part of the JET Top- ical Collaboration are in a separate report “Final Technical Report summarizing Purdue research activities as part of the DOE JET Topical Collaboration” (award DE-SC0004077).

  15. Effective equation of state of hot and dense matter in nuclear collisions around FAIR energy

    Directory of Open Access Journals (Sweden)

    Bravina L.

    2015-01-01

    Full Text Available The chemical and thermal equilibration in the central zone of heavy-ion collisions at energies around FAIR is studied within two microscopic models. Two systems are utilized for the analysis: (i central cubic cell of fixed volume V = 125 fm3 and (ii expanding central area of uniformly distributed energy density. It is found that kinetic, thermal, and chemical equilibration of the expanding hadronic matter are nearly approached in both systems for the period of 10–18 fm/c. The expansion proceeds almost isentropically. The extracted equation of state (EOS in P − ɛ plane has a linear dependence P = aɛ, where a ≡ c2s slightly increases with the collision energy from 0.12 to 0.145. Linear dependencies for the EOS are found also in T − μB and T − μS planes. The characteristic kinks observed in the last two phase diagrams are linked to inelastic freeze-out in the expanding fireball.

  16. Chiral Restoration and the Scalar and Vector Correlations in Hot and Dense Matter

    CERN Document Server

    Kunihiro, T

    2003-01-01

    First, it is pointed out that hadron/nuclear physics based on QCD should be regarded as ``condensed matter physics'' of the QCD vacuum. We indicate that phase shift analyses which respect chiral symmetry (ChS), analyticity and crossing symmetry of the scattering amplitude show the $sigma$ meson pole in the s-channel in the low mass region as well as the $rho$ meson pole in the $t$-channel in the pipi scattering in the scalar channel. We review recent developments in exploring possible precursory phenomena of partial restoration of chis in nuclear medium by examining the spectral function in the scalar and the vector channels. We emphasize that the wave function renormalization of the pion in the medium plays an essential role to induce the decrease of the pion decay constant as the order parameter of chiral transition. An emphasis is also put on the importance to examine the scalar and vector channels simultaneously for exploring the possible restoration of chiral symmetry.

  17. Indications for a critical end point in the phase diagram for hot and dense nuclear matter.

    Science.gov (United States)

    Lacey, Roy A

    2015-04-10

    Excitation functions for the Gaussian emission source radii difference (R_{out}^{2}-R_{side}^{2}) obtained from two-pion interferometry measurements in Au+Au (sqrt[s_{NN}]=7.7-200  GeV) and Pb+Pb (sqrt[s_{NN}]=2.76  TeV) collisions are studied for a broad range of collision centralities. The observed nonmonotonic excitation functions validate the finite-size scaling patterns expected for the deconfinement phase transition and the critical end point (CEP), in the temperature versus baryon chemical potential (T,μ_{B}) plane of the nuclear matter phase diagram. A finite-size scaling (FSS) analysis of these data suggests a second order phase transition with the estimates T^{cep}∼165  MeV and μ_{B}^{cep}∼95  MeV for the location of the critical end point. The critical exponents (ν≈0.66 and γ≈1.2) extracted via the same FSS analysis place this CEP in the 3D Ising model universality class.

  18. Dense baryonic matter in conformally-compensated hidden local symmetry: Vector manifestation and chiral symmetry restoration

    Science.gov (United States)

    Ma, Yong-Liang; Harada, Masayasu; Lee, Hyun Kyu; Oh, Yongseok; Park, Byung-Yoon; Rho, Mannque

    2014-08-01

    We find that, when the dilaton is implemented as a (pseudo-)Nambu-Goldstone boson using a conformal compensator or "conformon" in a hidden gauge symmetric Lagrangian written to O(p4) from which baryons arise as solitons, namely, skyrmions, the vector manifestation and chiral symmetry restoration at high density predicted in hidden local symmetry theory—which is consistent with Brown-Rho scaling—are lost or sent to infinite density. It is shown that they can be restored if in medium the behavior of the ω field is taken to deviate from that of the ρ meson in such a way that the flavor U(2) symmetry is strongly broken at increasing density. The hitherto unexposed crucial role of the ω meson in the structure of elementary baryon and multibaryon systems is uncovered in this work. In the state of half-skyrmions to which the skyrmions transform at a density n1/2≳n0 (where n0 is the normal nuclear matter density), characterized by the vanishing (space averaged) quark condensate but nonzero pion decay constant, the nucleon mass remains more or less constant at a value ≳60% of the vacuum value, indicating a large component of the nucleon mass that is not associated with the spontaneous breaking of chiral symmetry. We discuss its connection to the chiral-invariant mass m0 that figures in the parity-doublet baryon model.

  19. Degeneracy between WDM and coupled CDM: A clarifying note

    CERN Document Server

    Velten, Hermano; Caramês, Thiago R P

    2015-01-01

    Wei et al [PRD 88, 043510 (2013)] have proposed the existence of a cosmological degeneracy between warm dark matter (WDM), modified gravity and coupled cold dark matter (CDM) cosmologies at both the background expansion and the growth of density perturbation levels, i.e., corresponding cosmological data would not be able to differentiate such scenarios. Here, we will focus on the specific indistinguishability between a warm dark matter plus cosmological constant ($\\Lambda$) and coupled scalar field-CDM scenarios. Although the statement of Wei et al is true for very specific conditions we present a more complete discussion on this issue and show in more detail that these models are indeed distinguishable. We show that the degeneracy breaks down since coupled models leave a specific signature in the redshift space distortion data which is absent in the uncoupled warm dark matter cosmologies. Furthermore, we complement our claim by providing the reasons which suggest that even at nonlinear level a breaking of su...

  20. Properties of hot and dense matter created in relativistic heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Arsene, Ionut Cristian

    2009-07-01

    In this thesis we tried to characterize a few aspects of the rich field of relativistic heavy ion collisions at intermediate and high energies. In chapter 2 we used two different microscopic string models, UrQMD and QGSM, to study the formation and evolution of the locally equilibrated matter in the central zone of heavy ion collisions at energies spanning from sq root sNN approx 4 GeV up to 17.3 GeV. The calculations were performed both in the cubic central cell of fixed volume V = 5 centre dot 5 centre dot 5 fm3 and for the instantly expanding volume of homogeneous energy density. To decide whether or not equilibrium is reached we used a traditional approach based on the fulfillment of the conditions of kinetic, thermal and chemical equilibrium. Both models favor the formation of equilibrated matter for a period of about 10 fm/c in which the matter expands isentropically with constant entropy per baryon. The square of the speed of sound c{sub s}2 has been found to vary in UrQMD from 0.13 at AGS to 0.15 at SPS energies and in QGSM from 0.11 at AGS to 0.15 at SPS. In both models the rise in c{sub s}2 slows down at sq rootsNN approx 9 GeV. Chapter 3 describes the HYDJET++ model as a superposition of the soft, hydrotype state and the hard state resulting from multi-parton fragmentation. Both states are treated independently. The hard part is an NN collision generator called PYQUEN which modifies the 'standard' jet event obtained with the PYTHIA generator and includes radiative and collisional energy loss for partons. Initial state effects like shadowing are included also. The soft part is the thermal hadronic state generated on the chemical and thermal freeze-out hypersurfaces obtained from the parametrization of relativistic hydrodynamics. We found that this model gives a good description of soft observables at top RHIC energy, like the p{sub T} spectrum, elliptic flow and HBT correlations. The hard part of the model describes well the high-p{sub T

  1. Properties of hot and dense matter created in relativistic heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Arsene, Ionut Cristian

    2009-07-01

    In this thesis we tried to characterize a few aspects of the rich field of relativistic heavy ion collisions at intermediate and high energies. In chapter 2 we used two different microscopic string models, UrQMD and QGSM, to study the formation and evolution of the locally equilibrated matter in the central zone of heavy ion collisions at energies spanning from sq root sNN approx 4 GeV up to 17.3 GeV. The calculations were performed both in the cubic central cell of fixed volume V = 5 centre dot 5 centre dot 5 fm3 and for the instantly expanding volume of homogeneous energy density. To decide whether or not equilibrium is reached we used a traditional approach based on the fulfillment of the conditions of kinetic, thermal and chemical equilibrium. Both models favor the formation of equilibrated matter for a period of about 10 fm/c in which the matter expands isentropically with constant entropy per baryon. The square of the speed of sound c{sub s}2 has been found to vary in UrQMD from 0.13 at AGS to 0.15 at SPS energies and in QGSM from 0.11 at AGS to 0.15 at SPS. In both models the rise in c{sub s}2 slows down at sq rootsNN approx 9 GeV. Chapter 3 describes the HYDJET++ model as a superposition of the soft, hydrotype state and the hard state resulting from multi-parton fragmentation. Both states are treated independently. The hard part is an NN collision generator called PYQUEN which modifies the 'standard' jet event obtained with the PYTHIA generator and includes radiative and collisional energy loss for partons. Initial state effects like shadowing are included also. The soft part is the thermal hadronic state generated on the chemical and thermal freeze-out hypersurfaces obtained from the parametrization of relativistic hydrodynamics. We found that this model gives a good description of soft observables at top RHIC energy, like the p{sub T} spectrum, elliptic flow and HBT correlations. The hard part of the model describes well the high-p{sub T

  2. Parametric amplification and wavelength conversion of a 2.048-Tbit/s WDM PDM 16-QAM signal

    DEFF Research Database (Denmark)

    Hu, Hao; Jopson, R. M.; Gnauck, A. H.;

    2014-01-01

    We demonstrate polarisation-insensitive parametric amplification in highly nonlinear fibre of a 2.048-Tbit/s dense WDM PDM 16-QAM signal with ∼10 dB on-off gain and simultaneous wavelength conversion and phase conjugation, with mean Q2 penalties of only 0.6 dB and 0.4 dB....

  3. Monte Carlo approach to calculate proton stopping in warm dense matter within particle-in-cell simulations

    Science.gov (United States)

    Wu, D.; He, X. T.; Yu, W.; Fritzsche, S.

    2017-02-01

    A Monte Carlo approach to proton stopping in warm dense matter is implemented into an existing particle-in-cell code. This approach is based on multiple electron-electron, electron-ion, and ion-ion binary collision and accounts for both the free and the bound electrons in the plasmas. This approach enables one to calculate the stopping of particles in a more natural manner than existing theoretical treatment. In the low-temperature limit, when "all" electrons are bound to the nucleus, the stopping power coincides with the predictions from the Bethe-Bloch formula and is consistent with the data from the National Institute of Standard and Technology database. At higher temperatures, some of the bound electrons are ionized, and this increases the stopping power in the plasmas, as demonstrated by A. B. Zylstra et al. [Phys. Rev. Lett. 114, 215002 (2015)], 10.1103/PhysRevLett.114.215002. At even higher temperatures, the degree of ionization reaches a maximum and thus decreases the stopping power due to the suppression of collision frequency between projected proton beam and hot plasmas in the target.

  4. Bayesian inference of x-ray diffraction spectra from warm dense matter with the one-component-plasma model

    Science.gov (United States)

    Clérouin, Jean; Desbiens, Nicolas; Dubois, Vincent; Arnault, Philippe

    2016-12-01

    We show that the Bayesian inference of recently measured x-ray diffraction spectra from laser-shocked aluminum [L. B. Fletcher et al., Nat. Photon. 9, 274 (2015), 10.1038/nphoton.2015.41] with the one-component-plasma (OCP) model performs remarkably well at estimating the ionic density and temperature. This statistical approach requires many evaluations of the OCP static structure factor, which were done using a recently derived analytic fit. The atomic form factor is approximated by an exponential function in the diffraction window of the first peak. The electronic temperature is then estimated from a comparison of this approximated form factor with the electronic structure of an average atom model. Out-of-equilibrium states, with electrons hotter than ions, are diagnosed for the spectra obtained early after the pump, whereas at a late time delay the plasma is at thermal equilibrium. Apart from the present findings, this OCP-based modeling of warm dense matter has an important role to play in the interpretation of x-ray Thomson scattering measurements currently performed at large laser facilities.

  5. Optical Fiber Devices in WDM Networks

    Institute of Scientific and Technical Information of China (English)

    Shan Jiang; Yong Luo; Xinda Yin; Wei Shi; Qianggao Hu

    2003-01-01

    Crystal optics and fiber grating technology are two of the most important optical fiber device technologies.In this paper, we report several new devices developed in Accelink for WDM networks application.

  6. Equilibrium Analysis for Anycast in WDM Networks

    Institute of Scientific and Technical Information of China (English)

    唐矛宁; 王汉兴

    2005-01-01

    In this paper, the wavelength-routed WDM network, was analyzed for the dynamic case where the arrival of anycast requests was modeled by a state-dependent Poisson process. The equilibrium analysis was also given with the UWNC algorithm.

  7. Performance Monitoring in Transparent Reconfigurable WDM Networks

    Institute of Scientific and Technical Information of China (English)

    Chun-Kit.Chan; Frank; Tong

    2003-01-01

    This paper classifies and surveys different approaches proposed for performance monitoring, in particular the optical signal-to-noise ratio (OSNR) monitoring, in transparent reconfigurable WDM networks. Some considerations for future monitoring schemes are discussed.

  8. Optical Fiber Devices in WDM Networks

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Crystal optics and fiber grating technology are two of the most important optical fiber device technologies. In this paper, we report several new devices developed in Accelink for WDM networks application.

  9. GigaWaM—Next-Generation WDM-PON Enabling Gigabit Per-User Data Bandwidth

    DEFF Research Database (Denmark)

    Prince, Kamau; Gibbon, Timothy Braidwood; Rodes Lopez, Roberto;

    2012-01-01

    The “Gigabit access passive optical network using wavelength division multiplexing” project aims to implement 64-Gb/s data transmission over 20-km single-mode fiber. Per-user symmetric data rates of 1-Gb/s will be achieved using wavelength division multiplexing passive optical network (WDM......, and broadband internet) service over existing optical infrastructure, and also facilitate cost-effective dense wavelength division multiplexing for metro aggregation and mobile backhaul networks....

  10. The Galactic Halo in Mixed Dark Matter Cosmologies

    NARCIS (Netherlands)

    Anderhalden, D.; Diemand, J.; Bertone, G.; Macciò, A.V.; Schneider, A.

    2012-01-01

    A possible solution to the small scale problems of the cold dark matter (CDM) scenario is that the dark matter consists of two components, a cold and a warm one. We perform a set of high resolution simulations of the Milky Way halo varying the mass of the WDM particle (mWDM) and the cosmic dark

  11. Minimizing ADMs on WDM Directed Fiber Trees

    Institute of Scientific and Technical Information of China (English)

    ZHOU FengFeng (周丰丰); CHEN GuoLiang (陈国良); XU YinLong (许胤龙); GU Jun (顾钧)

    2003-01-01

    This paper proposes a polynomial-time algorithm for Minimum WDM/SONET Add/Drop Multiplexer Problem (MADM) on WDM directed fiber trees whether or not wavelength converters are used. It runs in time O(m2n), where n and m are the number of nodes of the tree and the number of the requests respectively. Incorporating T. Erlebach et al.'s work into the proposed algorithm, it also reaches the lower bound of the required wavelengths with greedy algorithms for the case without wavelength converters. Combined with some previous work, the algorithm reduces the number of required wavelengths greatly while using minimal number of ADMs for the case with limited wavelength converters. The experimental results show the minimal number of required ADMs on WDM directed fiber trees.

  12. Atoms in dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    More, R.M.

    1986-01-01

    Recent experiments with high-power pulsed lasers have strongly encouraged the development of improved theoretical understanding of highly charged ions in a dense plasma environment. This work examines the theory of dense plasmas with emphasis on general rules which govern matter at extreme high temperature and density. 106 refs., 23 figs.

  13. Single-mode vertically integrated waveguide photodetectors for WDM data receiver applications

    Science.gov (United States)

    Densmore, Adam S.; Pimenov, Kirill; Tolstikhin, Valery I.

    2004-12-01

    The advantages of monolithic integration of passive and active optoelectronic components into multifunctional PICs (photonic integrated circuits) are numerous and well known. In WDM transmission systems, where up to hundreds of wavelength channels may be present and must be manipulated on a per wavelength basis, the advantages of PICs containing wavelength (de)multiplexers and arrays of active components rapidly multiply. This has been exploited in our earlier reported SurePath family of InP-based PICs for optical channel monitoring / equalization, which contain an echelle grating demultiplexer and single-mode vertically integrated waveguide photodetectors / electroabsorption attenuators inserted into each of its output channels. Now, the same design principles and fabrication techniques have been utilized for the development of a dense WDM data receiver. This paper concentrates on the key building block of such a component, the single-mode vertically integrated waveguide photodetector. A detailed characterization and analysis of the device performance are presented.

  14. WDM in Courses of Communication Technologies

    Directory of Open Access Journals (Sweden)

    Miloslav Filka

    2008-01-01

    Full Text Available This conference paper shows and demonstrates how modern technologies (such as WDM – Wavelength Division Multiplex were introduced to students of Optical Networks lectured at Brno University of Technology, Faculty of Electrical Engineering and Communication, Dept. of Telecommunications.

  15. Automatically output-power-controlled WDM EDFA

    Science.gov (United States)

    Choi, Bo-Hun; Lee, Sang Soo; Kim, Chang-Bong; Ko, Jesoo

    2006-09-01

    Our amplifier using an all optical method and a fixed GFF achieved automatic gain flatness through all C-band without any NF degradation, and simultaneously a constant 25 dB gain, while input signals were varied between one channel and forty WDM channels.

  16. Flexible Twin Open Ring Metro WDM Network

    Institute of Scientific and Technical Information of China (English)

    Susumu Kinoshita; Cechan Tian; Satoru Ohdate; Koji Takeguchi; Yasuhiko Aoki

    2003-01-01

    We have demonstrated a flexible twin open ring WDM network for metro applications. A pair of optical switches in the network keeps the fiber rings open to prevent signal circulation. Traffics are broadcast to every node and selected at the receiving side. Superior transmission and protection switching are proved.

  17. Wavelength-agnostic WDM-PON System

    DEFF Research Database (Denmark)

    Wagner, Christoph; Eiselt, Michael; Zou, S.

    2016-01-01

    Next-generation WDM-PON solutions for metro and access systems will take advantage of remotely controlled wavelength-tunable ONUs to keep system costs as low as possible. For such a purpose, each ONU signal can be labeled by a pilot tone modulated onto the optical data stream. We report...

  18. Next-Generation WDM Network Design and Routing

    Science.gov (United States)

    Tsang, Danny H. K.; Bensaou, Brahim

    2003-10-01

    Call for Papers The Editors of JON are soliciting papers on WDM Network Design and Routing. The aim in this focus issue is to publish original research on topics including - but not limited to - the following: - WDM network architectures and protocols - GMPLS network architectures - Wavelength converter placement in WDM networks - Routing and wavelength assignment (RWA) in WDM networks - Protection and restoration strategies and algorithms in WDM networks - Traffic grooming in WDM networks - Dynamic routing strategies and algorithms - Optical burst switching - Support of multicast - Protection and restoration in WDM networks - Performance analysis and optimization in WDM networks Manuscript Submission To submit to this special issue, follow the normal procedure for submission to JON, indicating "WDM Network Design" in the "Comments" field of the online submission form. For all other questions relating to this focus issue, please send an e-mail to jon@osa.org, subject line "WDM Network Design." Additional information can be found on the JON website: http://www.osa-jon.org/submission/. Schedule - Paper Submission Deadline: November 1, 2003 - Notification to Authors: January 15, 2004 - Final Manuscripts to Publisher: February 15, 2004 - Publication of Focus Issue: February/March 2004

  19. Average-atom model for two-temperature states and ionic transport properties of aluminum in the warm dense matter regime

    Science.gov (United States)

    Hou, Yong; Fu, Yongsheng; Bredow, Richard; Kang, Dongdong; Redmer, Ronald; Yuan, Jianmin

    2017-03-01

    The average-atom model combined with the hyper-netted chain approximation is an efficient tool for electronic and ionic structure calculations for warm dense matter. Here we generalize this method in order to describe non-equilibrium states with different electron and ion temperature as produced in laser-matter interactions on ultra-short time scales. In particular, the electron-ion and ion-ion correlation effects are considered when calculating the electron structure. We derive an effective ion-ion pair-potential using the electron densities in the framework of temperature-depended density functional theory. Using this ion-ion potential we perform molecular dynamics simulations in order to determine the ionic transport properties such as the ionic diffusion coefficient and the shear viscosity through the ionic velocity autocorrelation functions.

  20. INVESTIGATION ON HYBRID WDM (DWDM+CWDM FREE SPACE OPTICAL COMMUNICATION SYSTEM

    Directory of Open Access Journals (Sweden)

    S. Robinson

    2015-12-01

    Full Text Available Free Space Optical (FSO communication is being realized as an effective solution for future accessing networks, offering light passed through air. The performance of FSO can be primarily degraded by various atmospheric attenuation namely, rain, fog, haze and snow. At present, hybridization of Dense Wavelength Division Multiplexing (DWDM with Coarse Wavelength Division Multiplexing (CWDM becomes necessary to scale the speed and high bandwidth of the services. In this paper, hybrid WDM system is proposed, designed and the network parameters such as Bit Error Rate (BER, Quality Factor and receiver sensitivity are analyzed with respect to link distance for various weather conditions. For investigation, 4 CWDM and 8 DWDM channels are considered whose corresponding channel spacing is 20nm and 0.8nm, respectively. From the simulation, it is investigated that the average link distance of proposed hybrid WDM-FSO system for DWDM and CWDM system at very clear condition are around 810km and 780km. The proposed hybrid WDM based FSO system is designed to handle the quality of transmission for 12 users, each at a data rate of 2.5Gbps.

  1. Shock-adiabatic to quasi-isentropic compression of warm dense helium up to 150 GPa

    Science.gov (United States)

    Zheng, J.; Chen, Q. F.; Gu, Y. J.; Li, J. T.; Li, Z. G.; Li, C. J.; Chen, Z. Y.

    2017-06-01

    Multiple reverberation compression can achieve higher pressure, higher temperature, but lower entropy. It is available to provide an important validation for the elaborate and wider planetary models and simulate the inertial confinement fusion capsule implosion process. In the work, we have developed the thermodynamic and optical properties of helium from shock-adiabatic to quasi-isentropic compression by means of a multiple reverberation technique. By this technique, the initial dense gaseous helium was compressed to high pressure and high temperature and entered the warm dense matter (WDM) region. The experimental equation of state (EOS) of WDM helium in the pressure-density-temperature (P-ρ -T) range of 1 -150 GPa , 0.1 -1.1 g c m-3 , and 4600-24 000 K were measured. The optical radiations emanating from the WDM helium were recorded, and the particle velocity profiles detecting from the sample/window interface were obtained successfully up to 10 times compression. The optical radiation results imply that dense He has become rather opaque after the 2nd compression with a density of about 0.3 g c m-3 and a temperature of about 1 eV. The opaque states of helium under multiple compression were analyzed by the particle velocity measurements. The multiple compression technique could efficiently enhanced the density and the compressibility, and our multiple compression ratios (ηi=ρi/ρ0,i =1 -10 ) of helium are greatly improved from 3.5 to 43 based on initial precompressed density (ρ0) . For the relative compression ratio (ηi'=ρi/ρi -1) , it increases with pressure in the lower density regime and reversely decreases in the higher density regime, and a turning point occurs at the 3rd and 4th compression states under the different loading conditions. This nonmonotonic evolution of the compression is controlled by two factors, where the excitation of internal degrees of freedom results in the increasing compressibility and the repulsive interactions between the

  2. Traffic Scheduling in WDM Passive Optical Network with Delay Guarantee

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    WDM passive optical network becomes more favorable as the required bandwidth increases, but currently few media access control algorithms adapted to WDM access network. This paper presented a new scheduling algorithm for bandwidth sharing in WDM passive optical networks, which provides per-flow delay guarantee and supports variable-length packets scheduling. Through theoretical analysis and simulation, the end-to-end delay bound and throughput fairness of the algorithm was demonstrated.

  3. Deterministic digital WDM LAN for controlled configurations

    Science.gov (United States)

    Mazurowski, John

    2013-09-01

    This work introduces the concept of a digital Wavelength Division Multiplexed (WDM) network for small avionic and space platforms. For packaging and heat transfer efficiency, all optical wavelength sources occupy a common location. Addressable wavelengths are allocated to each receiver, which may be reached by selection or tuning of a transmitter wavelength. Individual delays may be applied to assure synchronization at each receiver. The output of each individual source wavelength is pre-modulated with a clock signal. Signal modulation is applied by passing or rejecting the clock signals. Due to the simplicity of the modulation, the control plane functions can be merged with the data plane functions. Although the concept is based on a single data rate, the digital WDM LAN concept can possibly be extended to process packet and analog payloads.

  4. Traffic Grooming in Bidirectional WDM Ring Networks

    CERN Document Server

    Bermond, Jean-Claude; Valls, Ignasi Sau

    2009-01-01

    We study the minimization of ADMs (Add-Drop Multiplexers) in optical WDM bidirectional rings considering symmetric shortest path routing and all-to-all unitary requests. We precisely formulate the problem in terms of graph decompositions, and state a general lower bound for all the values of the grooming factor $C$ and $N$, the size of the ring. We first study exhaustively the cases C=1, $C = 2$, and C=3, providing improved lower bounds, optimal constructions for several infinite families, as well as asymptotically optimal constructions and approximations. We then study the case $C>3$, focusing specifically on the case $C = k(k+1)/2$ for some $k \\geq 1$. We give optimal decompositions for several congruence classes of $N$ using the existence of some combinatorial designs. We conclude with a comparison of the cost functions in unidirectional and bidirectional WDM rings.

  5. Active plasmonics in WDM traffic switching applications

    DEFF Research Database (Denmark)

    Papaioannou, S.; Kalavrouziotis, D.; Vyrsokinos, K.;

    2012-01-01

    With metal stripes being intrinsic components of plasmonic waveguides, plasmonics provides a "naturally" energy-efficient platform for merging broadband optical links with intelligent electronic processing, instigating a great promise for low-power and small-footprint active functional circuitry....... The first active Dielectric-Loaded Surface Plasmon Polariton (DLSPP) thermo-optic (TO) switches with successful performance in single-channel 10 Gb/s data traffic environments have led the inroad towards bringing low-power active plasmonics in practical traffic applications. In this article, we introduce...... active plasmonics into Wavelength Division Multiplexed (WDM) switching applications, using the smallest TO DLSPP-based Mach-Zehnder interferometric switch reported so far and showing its successful performance in 4310 Gb/s low-power and fast switching operation. The demonstration of the WDM...

  6. Average-atom treatment of relaxation time in x-ray Thomson scattering from warm dense matter.

    Science.gov (United States)

    Johnson, W R; Nilsen, J

    2016-03-01

    The influence of finite relaxation times on Thomson scattering from warm dense plasmas is examined within the framework of the average-atom approximation. Presently most calculations use the collision-free Lindhard dielectric function to evaluate the free-electron contribution to the Thomson cross section. In this work, we use the Mermin dielectric function, which includes relaxation time explicitly. The relaxation time is evaluated by treating the average atom as an impurity in a uniform electron gas and depends critically on the transport cross section. The calculated relaxation rates agree well with values inferred from the Ziman formula for the static conductivity and also with rates inferred from a fit to the frequency-dependent conductivity. Transport cross sections determined by the phase-shift analysis in the average-atom potential are compared with those evaluated in the commonly used Born approximation. The Born approximation converges to the exact cross sections at high energies; however, differences that occur at low energies lead to corresponding differences in relaxation rates. The relative importance of including relaxation time when modeling x-ray Thomson scattering spectra is examined by comparing calculations of the free-electron dynamic structure function for Thomson scattering using Lindhard and Mermin dielectric functions. Applications are given to warm dense Be plasmas, with temperatures ranging from 2 to 32 eV and densities ranging from 2 to 64 g/cc.

  7. Detailed analysis of hollow ions spectra from dense matter pumped by X-ray emission of relativistic laser plasma

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, S. B., E-mail: sbhanse@sandia.gov, E-mail: anatolyf@hotmail.com [Sandia National Laboratories, Albuquerque, New Mexico 87123 (United States); Colgan, J.; Abdallah, J. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Faenov, A. Ya., E-mail: sbhanse@sandia.gov, E-mail: anatolyf@hotmail.com [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); Quantum Beam Science Directorate, Japan Atomic Energy Agency, Kyoto 619-0215 (Japan); Pikuz, S. A.; Skobelev, I. Yu. [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); Wagenaars, E.; Culfa, O.; Dance, R. J.; Tallents, G. J.; Rossall, A. K.; Woolsey, N. C. [York Plasma Institute, Department of Physics, University of York, York YO10 5DD (United Kingdom); Booth, N.; Lancaster, K. L. [Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom); Evans, R. G. [Department of Physics, Imperial College, London SW7 2AZ (United Kingdom); Gray, R. J.; McKenna, P. [SUPA, Department of Physics, University of Strathclyde, Glasgow G4 ONG (United Kingdom); Kaempfer, T.; Schulze, K. S. [Helmholtzinstitut Jena, Jena D-07743 (Germany); Uschmann, I. [Helmholtzinstitut Jena, Jena D-07743 (Germany); Institut für Optik und Quantenelektronic, Friedrich-Schiller-Universität Jena, Max-Wien Platz 1, Jena, D-07743 (Germany); and others

    2014-03-15

    X-ray emission from hollow ions offers new diagnostic opportunities for dense, strongly coupled plasma. We present extended modeling of the x-ray emission spectrum reported by Colgan et al. [Phys. Rev. Lett. 110, 125001 (2013)] based on two collisional-radiative codes: the hybrid-structure Spectroscopic Collisional-Radiative Atomic Model (SCRAM) and the mixed-unresolved transition arrays (MUTA) ATOMIC model. We show that both accuracy and completeness in the modeled energy level structure are critical for reliable diagnostics, investigate how emission changes with different treatments of ionization potential depression, and discuss two approaches to handling the extensive structure required for hollow-ion models with many multiply excited configurations.

  8. Probing the neutron star interior and the Equation of State of cold dense matter with the SKA

    CERN Document Server

    Watts, Anna; Espinoza, Cristobal; Andersson, Nils; Antoniadis, John; Antonopoulou, Danai; Buchner, Sarah; Dai, Shi; Demorest, Paul; Freire, Paulo; Hessels, Jason; Margueron, Jerome; Oertel, Micaela; Patruno, Alessandro; Possenti, Andrea; Ransom, Scott; Stairs, Ingrid; Stappers, Ben

    2015-01-01

    With an average density higher than the nuclear density, neutron stars (NS) provide a unique test-ground for nuclear physics, quantum chromodynamics (QCD), and nuclear superfluidity. Determination of the fundamental interactions that govern matter under such extreme conditions is one of the major unsolved problems of modern physics, and -- since it is impossible to replicate these conditions on Earth -- a major scientific motivation for SKA. The most stringent observational constraints come from measurements of NS bulk properties: each model for the microscopic behaviour of matter predicts a specific density-pressure relation (its `Equation of state', EOS). This generates a unique mass-radius relation which predicts a characteristic radius for a large range of masses and a maximum mass above which NS collapse to black holes. It also uniquely predicts other bulk quantities, like maximum spin frequency and moment of inertia. The SKA, in Phase 1 and particularly in Phase 2 will, thanks to the exquisite timing pr...

  9. Observational implications of a strong phase transition in the dense matter equation of state for the rotational evolution of neutron stars

    CERN Document Server

    Bejger, M; Haensel, P; Zdunik, J L; Fortin, M

    2016-01-01

    We explore the implications of a strong first-order phase transition region in the dense matter equation of state in the interiors of rotating neutron stars, and the resulting creation of two disjoint families of neutron-stars' configurations (the so-called high-mass twins). Rotating, axisymmetric and stationary stellar configurations are obtained numerically in the framework of general relativity, and their global parameters and stability are studied. The equation of state-induced instability divides stable neutron star configurations into two disjoint families: neutron stars (second family) and hybrid stars (third family), with an overlapping region in mass, the high-mass twin star region. These two regions are divided by an instability strip. Its existence has interesting astrophysical consequences for rotating neutron stars. We note that it provides a "natural" explanation for the rotational frequency cutoff in the observed distribution of neutron stars spins, and for the apparent lack of back-bending in ...

  10. Examination of strangeness instabilities and effects of strange meson couplings in dense strange hadronic matter and compact stars

    Science.gov (United States)

    Torres, James R.; Gulminelli, Francesca; Menezes, Débora P.

    2017-02-01

    Background: The emergence of hyperon degrees of freedom in neutron star matter has been associated to first-order phase transitions in some phenomenological models, but conclusions on the possible physical existence of an instability in the strangeness sector are strongly model dependent. Purpose: The purposes of the present study are to assess whether strangeness instabilities are related to specific values of the largely unconstrained hyperon interactions and to study the effect of the strange meson couplings on phenomenological properties of neutron stars and supernova matter, once these latter are fixed to fulfill the constraints imposed by hypernuclear data. Method: We consider a phenomenological relativistic mean field model (RMF) model sufficiently simple to allow a complete exploration of the parameter space. Results: We show that no instability at supersaturation density exists for the RMF model, as long as the parameter space is constrained by basic physical requirements. This is at variance with a nonrelativistic functional, with a functional behavior fitted through ab initio calculations. Once the study is extended to include the full octet, we show that the parameter space allows reasonable radii for canonical neutron stars as well as massive stars above two-solar mass, together with an important strangeness content of the order of 30%, slightly decreasing with increasing entropy, even in the absence of a strangeness-driven phase transition. Conclusions: We conclude that the hyperon content of neutron stars and supernova matter cannot be established with present constraints, and is essentially governed by the unconstrained coupling to the strange isoscalar meson.

  11. Exotic dense-matter states pumped by a relativistic laser plasma in the radiation-dominated regime.

    Science.gov (United States)

    Colgan, J; Abdallah, J; Faenov, A Ya; Pikuz, S A; Wagenaars, E; Booth, N; Culfa, O; Dance, R J; Evans, R G; Gray, R J; Kaempfer, T; Lancaster, K L; McKenna, P; Rossall, A L; Skobelev, I Yu; Schulze, K S; Uschmann, I; Zhidkov, A G; Woolsey, N C

    2013-03-22

    In high-spectral resolution experiments with the petawatt Vulcan laser, strong x-ray radiation of KK hollow atoms (atoms without n = 1 electrons) from thin Al foils was observed at pulse intensities of 3 × 10(20) W/cm(2). The observations of spectra from these exotic states of matter are supported by detailed kinetics calculations, and are consistent with a picture in which an intense polychromatic x-ray field, formed from Thomson scattering and bremsstrahlung in the electrostatic fields at the target surface, drives the KK hollow atom production. We estimate that this x-ray field has an intensity of >5 × 10(18) W/cm(2) and is in the 3 keV range.

  12. Equation of State, Spectra and Composition of Hot and Dense Infinite Hadronic Matter in a Microscopic Transport Model

    CERN Document Server

    Belkacem, M; Bass, S A; Bleicher, M; Bravina, L V; Gorenstein, M I; Konopka, J; Neise, L; Spieles, C; Soff, S; Weber, H; Stöcker, H; Greiner, W

    1998-01-01

    Equilibrium properties of infinite relativistic hadron matter are investigated using the Ultrarelativistic Quantum Molecular Dynamics (UrQMD) model. The simulations are performed in a box with periodic boundary conditions. Equilibration times depend critically on energy and baryon densities. Energy spectra of various hadronic species are shown to be isotropic and consistent with a single temperature in equilibrium. The variation of energy density versus temperature shows a Hagedorn-like behavior with a limiting temperature of 130$\\pm$10 MeV. Comparison of abundances of different particle species to ideal hadron gas model predictions show good agreement only if detailed balance is implemented for all channels. At low energy densities, high mass resonances are not relevant; however, their importance raises with increasing energy density. The relevance of these different conceptual frameworks for any interpretation of experimental data is questioned.

  13. Stocks and dynamics of particulate and dissolved organic matter in a large, shallow eutrophic lake (Taihu, China) with dense cyanobacterial blooms

    Science.gov (United States)

    Shi, Limei; Huang, Yaxin; Lu, Yaping; Chen, Feizhou; Zhang, Min; Yu, Yang; Kong, Fanxiang

    2017-08-01

    Cyanobacterial blooms occur in eutrophic lakes worldwide, and greatly impair these ecosystems. To explore influences of cyanobacterial blooms on dynamics of both particulate organic matter (POM) and dissolved organic matter (DOM), which are at the base of the food chain, an investigation was conducted from December 2014 to November 2015 that included various stages of the seasonal cyanobacterial blooms (dominated by Microcystis) in a large-shallow eutrophic Chinese lake (Taihu Lake). Data from eight sites of the lake are compiled into a representative seasonal cycle to assess general patterns of POM and DOM dynamics. Compared to December, 5-fold and 3.5-fold increases were observed in July for particulate organic carbon (POC, 3.05-15.37 mg/L) and dissolved organic carbon (DOC, 5.48-19.25 mg/L), respectively, with chlorophyll a (Chl a) concentrations varying from 8.2 to 97.7 μg/L. Approximately 40% to 76% of total organic carbon was partitioned into DOC. All C, N, and P in POM and DOC were significantly correlated with Chl a. POC:Chl a ratios were low, whereas proportions of the estimated phytoplankton-derived organic matter in total POM were high during bloom seasons. These results suggested that contributions of cyanobacterial blooms to POM and DOC varied seasonally. Seasonal average C:P ratios in POM and DOM varied from 79 to 187 and 299 to 2 175, respectively. Both peaked in July and then sharply decreased. Redundancy analysis revealed that Chl a explained most of the variations of C:N:P ratios in POM, whereas temperature was the most explanatory factor for DOM. These findings suggest that dense cyanobacterial blooms caused both C-rich POM and DOM, thereby providing clues for understanding their influence on ecosystems.

  14. Wavelength-agnostic WDM-PON System

    DEFF Research Database (Denmark)

    Wagner, Christoph; Eiselt, Michael; Zou, S.;

    2016-01-01

    Next-generation WDM-PON solutions for metro and access systems will take advantage of remotely controlled wavelength-tunable ONUs to keep system costs as low as possible. For such a purpose, each ONU signal can be labeled by a pilot tone modulated onto the optical data stream. We report...... on the standardization status of this lowcost system in the new ITU-T G.metro draft recommendation, in the context of autonomous tuning. We also discuss some low-effort implementations of the pilot-tone labels and investigate the impact of these labels on the transmission channels....

  15. Multimedia Traffic Routing in Multilayer WDM Networks

    CERN Document Server

    Amphawan, Angela; Hasan, Hassanuddin

    2012-01-01

    The advent of real-time multimedia services over the Internet has stimulated new technologies for expanding the information carrying capacity of optical network backbones. Multilayer wavelength division multiplexing (WDM) packet switching is an emerging technology for increasing the bandwidth of optical networks. Two algorithms for the routing of the multimedia traffic flows were applied: (i) Capacitated Shortest Path First (CSPF) routing, which minimizes the distance of each flow linking the given source and destination nodes and satisfying capacity constraints; and (ii) Flow Deviation Algorithm (FDA) routing, which minimizes the network?wide average packet delay.

  16. Testing the EoS of dark matter with cosmological observations

    CERN Document Server

    Avelino, Arturo; Nucamendi, Ulises

    2012-01-01

    We explore the cosmological constraints on the parameter w_dm of the dark matter barotropic equation of state (EoS) to investigate the "warmness" of the dark matter fluid. The model is composed by the dark matter and dark energy fluids in addition to the radiation and baryon components. We constrain the values of w_dm using the latest cosmological observations that measure the expansion history of the Universe. When w_dm is estimated together with the parameter w_de of the barotropic EoS of dark energy we found that the cosmological data favor a value of w_dm = 0.006 +- 0.001, suggesting a -warm- dark matter, and w_de= -1.11 +- 0.03$ that corresponds to a phantom dark energy, instead of favoring a cold dark matter and a cosmological constant (w_dm = 0, w_de = -1). When w_dm is estimated alone but assuming w_de = -1, -1.1, -0.9, we found w_dm = 0.009 +- 0.002, 0.006 +- 0.002, 0.012 +- 0.002 respectively, where the errors are at 3 sigma (99.73%), i.e., w_dm > 0 with at least 99.73% of confidence level. When (w_...

  17. Scheme of a WDM Time-Limited RAM for OPS

    Institute of Scientific and Technical Information of China (English)

    Shuguang Zhu; Anshi Xu; Hongxi Yin; Deming Wu; Xuzong Chen

    2003-01-01

    We propose a new idea of utilizing Multiple Electromagnetically Induced Transparency Concurrence within a Single Medium to fullfill optical packet buffering and theoretically design a Wavelength Division Multiplexing (WDM) Random Access Memory (RAM).

  18. Dense Breasts

    Science.gov (United States)

    ... also appear white on mammography, they can be hidden by or within dense breast tissue. Other imaging ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed ...

  19. Novel Node Structures for IP over WDM Networks

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    IP over WDM is being envisioned as one of the most attractive architectures for the next generation Internet. This paper introduces two novel backbone node structures for IP over WDM networks. These node structures can be used as improvement approaches to DPDP (default path and dedicated path) method. The flow classifiers, which are the main components of these node structures, and the performance metrics of these structures, are also discussed.

  20. Export policies for multi-domain WDM networks

    DEFF Research Database (Denmark)

    Manolova, Anna Vasileva; Ruepp, Sarah Renée

    2010-01-01

    We analyze the performance of six export policies for a multi-domain routing protocol in WDM networks. We show that providing many AS-disjoint paths for survivability and load-balancing does not necessarily guarantee the lowest connection blocking......We analyze the performance of six export policies for a multi-domain routing protocol in WDM networks. We show that providing many AS-disjoint paths for survivability and load-balancing does not necessarily guarantee the lowest connection blocking...

  1. Laser shocks on helium, hydrogen and diamond: an experimental study of the warm dense matter zone; Chocs laser sur l'helium, l'hydrogene et le diamant: une etude experimentale de la 'Warm Dense Matter'

    Energy Technology Data Exchange (ETDEWEB)

    Brygoo, St

    2006-11-15

    The purpose of this work was to develop a new approach of laser shocks on pre-compressed targets in order to collect data concerning the equation of state in the warm dense matter zone of the phase diagram. The accuracy of the measurement has been increased by the use of a new metrology based on quartz. Quartz is considered as a standard for the measurement of both the pressure and the density, a model of an isentropic relaxation based on a Grueneisen type approximation has been developed. By combining laser shocks with diamond anvil cells and by using this new metrology, we have investigated the following systems: diamond, helium, hydrogen, deuterium and hydrogen-helium mixtures. The results for helium agree very well with the predictions of the Saumon-Chabrier model. The results for deuterium are consistent with the latest results found in literature. As for the results concerning hydrogen, they have showed the limits of the quartz-based metrology. In fact, by being so little dense we are at the limit of the application range of the quartz relaxation. A mixture of helium-hydrogen (50 %) has been investigated, no sign of phase separation has been found.

  2. Dynamic multicast traffic grooming in WDM networks

    Institute of Scientific and Technical Information of China (English)

    CHENG Xiao-jun; GE Ning; FENG Chong-xi

    2006-01-01

    Dynamic multicast traffic grooming in wavelength division multiplexing (WDM) networks was analyzed to minimize networkwide costs and to increase the network resource utilization.A network model was developed for dynamic multicast traffic grooming with resource constraints and an algorithm that can provide quality of service (QoS)was proposed.The QoS is measured by the maximum number of lightpaths passing between the source and the destinations.The blocking probability of the algorithm was assessed in simulations.The results show that a higher QoS requirement results in higher blocking probability,and when the QoS requirement is low,changes in the QoS requirements have only small effects on the blocking probability.

  3. DYNAMIC CONGESTION CONTROL IN WDM OPTICAL NETWORK

    Directory of Open Access Journals (Sweden)

    Sangita Samajpati

    2013-02-01

    Full Text Available This paper is based on Wavelength Division Multiplexing (WDM optical networking. In this optical networking, prior to data transfer, lightpath establishment between source and destination nodes is usually carried out through a wavelength reservation protocol. This wavelength is reserved corresponding to a route between the source and destination and the route is chosen following any standard routing protocol based on shortest path. The backward reservation protocol is implemented initially. A fixed connected and weighted network is considered. The inputs of this implementation are the fixed network itself and its corresponding shortest path matrix. After this initial level of implementation, the average node usage over a time period is calculated and various thresholds for node usage are considered. Above threshold value, request arriving at that path selects its next shortest path. This concept is implemented on various wavelengths. The output represents the performance issues of dynamic congestion control.

  4. OTDM-to-WDM Conversion Based on Time-to-Frequency Mapping by Time-Domain Optical Fourier Transformation

    DEFF Research Database (Denmark)

    Palushani, Evarist; Mulvad, Hans Christian Hansen; Galili, Michael

    2012-01-01

    a dispersive medium followed by phase modulation; the latter being achieved by a four-wave mixing process with linearly chirped pump pulses. Both numerical and experimental investigations of the OTDM-to-WDM conversion technique are carried out. Experimental validations are performed on......This paper reports on the utilization of the timedomain optical Fourier transformation (OFT) technique for serial-to-parallel conversion of optical time division multiplexed (OTDM) data tributaries into dense wavelength division multiplexed (DWDM) channels. The OFT is implemented by using...

  5. An effective dynamic reconfiguration algorithm for IP over WDM networks

    Science.gov (United States)

    Yu, Hongfang; Zhou, Tao; Wang, Sheng; Li, Lemin

    2005-02-01

    WDM (Wavelength Division Multiplexing) technology can provide multiple wavelengths on a fiber. IP directly over WDM (or IP over WDM) has become the hot topic of industry. A promising approach for building an IP over WDM network is that a logical network consisting of the wavelength channels (lightpaths) is built on the physical WDM network. Then, IP traffic is carried on the logical topology, by utilizing the MPLS (Multiple Protocol Label Switching) or GMPLS (Generalized MPLS). When the traffic demand pattern changes in the IP layer, the network performance may become poor. In order to improve the network performance, the virtual topology can be reconfigured to suit the changing traffic patterns. In this paper, dynamic slowly-adaptation scheme (e.g. tearing down a lightpath that is lightly loaded or setting up a new lightpath when congestion occurs) is adopted. How to select the source and the destination nodes of the new lightpath to be added and the underutilized lightpath to be deleted if it is necessary to do so is our key issue. Four selection ways are developed. These ways are evaluated through detail simulations and various performances are investigated.

  6. Survivable Lightpath Routing in WDM Optical Networks

    Institute of Scientific and Technical Information of China (English)

    LIUFengqing; ZENGQingji; ZHUXu; YANGXudong; XIAOShilin

    2004-01-01

    In IP over WDM networks, when a failure(such as a fiber cut) occurs, the service restoration can be implemented by dynamic routing in IP layer. But it needs that the logical topology remains connected after any physical link failure. Otherwise, IP layer cannot find an alternate path to restore the service. The problem of routing logical links (lightpaths) on a physical network topology in a way that the logical topology remains connected in the event of single physical link failure is called survivabl erouting. In this paper~ we address the survivable routing problem by proposing a new ILP algorithm that works well with sparse-connected logical topologies. The necessary and sufficient conditions for survivable routing are simplified, which greatly reduces the number of survivable constraints. Based-on the simplified conditions, a new ILP formulation with K-shortest paths as alternate paths for a logical link is presented, which mainly reduces the number of ILP variables. Finally, numerical results are given and discussed to show that most survivable routing solutions can be found with our algorithms, and the time needed to find such a survivable routing solution is much smaller than other similar methods.

  7. P3: An installation for high-energy density plasma physics and ultra-high intensity laser–matter interaction at ELI-Beamlines

    Directory of Open Access Journals (Sweden)

    S. Weber

    2017-07-01

    Full Text Available ELI-Beamlines (ELI-BL, one of the three pillars of the Extreme Light Infrastructure endeavour, will be in a unique position to perform research in high-energy-density-physics (HEDP, plasma physics and ultra-high intensity (UHI (>1022W/cm2 laser–plasma interaction. Recently the need for HED laboratory physics was identified and the P3 (plasma physics platform installation under construction in ELI-BL will be an answer. The ELI-BL 10 PW laser makes possible fundamental research topics from high-field physics to new extreme states of matter such as radiation-dominated ones, high-pressure quantum ones, warm dense matter (WDM and ultra-relativistic plasmas. HEDP is of fundamental importance for research in the field of laboratory astrophysics and inertial confinement fusion (ICF. Reaching such extreme states of matter now and in the future will depend on the use of plasma optics for amplifying and focusing laser pulses. This article will present the relevant technological infrastructure being built in ELI-BL for HEDP and UHI, and gives a brief overview of some research under way in the field of UHI, laboratory astrophysics, ICF, WDM, and plasma optics.

  8. 32-core Dense SDM Unidirectional Transmission of PDM-16QAM Signals Over 1600 km Using Crosstalk-managed Single-mode Heterogeneous Multicore Transmission Line

    DEFF Research Database (Denmark)

    Mizuno, Takayuki; Shibahara, K.; Ono, Hirotaka;

    2016-01-01

    We demonstrate 32-core dense space-division multiplexed (DSDM) unidirectional transmission of PDM-16QAM 20-WDM signals over 1644.8 km employing a low-crosstalk single-mode heterogeneous 32-core fiber in a partial recirculating-loop system.......We demonstrate 32-core dense space-division multiplexed (DSDM) unidirectional transmission of PDM-16QAM 20-WDM signals over 1644.8 km employing a low-crosstalk single-mode heterogeneous 32-core fiber in a partial recirculating-loop system....

  9. 12-core x 3-mode Dense Space Division Multiplexed Transmission over 40 km Employing Multi-carrier Signals with Parallel MIMO Equalization

    DEFF Research Database (Denmark)

    Mizuno, T.; Kobayashi, T.; Takara, H.;

    2014-01-01

    We demonstrate dense SDM transmission of 20-WDM multi-carrier PDM-32QAM signals over a 40-km 12-core x 3-mode fiber with 247.9-b/s/Hz spectral efficiency. Parallel MIMO equalization enables 21-ns DMD compensation with 61 TDE taps per subcarrier.......We demonstrate dense SDM transmission of 20-WDM multi-carrier PDM-32QAM signals over a 40-km 12-core x 3-mode fiber with 247.9-b/s/Hz spectral efficiency. Parallel MIMO equalization enables 21-ns DMD compensation with 61 TDE taps per subcarrier....

  10. Integrated Differentiated Survivability in IP over WDM Networks

    Institute of Scientific and Technical Information of China (English)

    Wei Wei; Qing-Ji Zeng

    2004-01-01

    The problem of differentiated Multi-Layer Integrated Survivability (MLIS) in IP over WDM networks is studied, which is decomposed into three sub-problems: survivable strategies design (SSD), spare capacity dimensioning (SCD), and dynamic survivable routing (DSR). A related work of network survivability in IP over WDM networks is firstly provided, and adaptive survivable strategies are also designed. A new Integrated Shared Pool (ISP) approach for SCD is then proposed, which is formulated by using integer-programming theory. Moreover, a novel survivable routing scheme called Differentiated Integrated Survivability Algorithm (DISA) for DSR is developed. Simulation results show that the proposed integrated survivability scheme performs much better than other solutions (e.g., "highest layer recovery" and "lowest layer recovery" schemes) in terms of traffic blocking ratio, spare resource requirement, and average traffic recovery ratio in IP over WDM networks.

  11. What can the outskirts of galaxies tell us about dark matter?

    CERN Document Server

    Power, Chris

    2016-01-01

    Deep observations of galaxy outskirts reveal faint extended stellar components (ESCs) of streams, shells, and halos, which are ghostly remnants of the tidal disruption of satellite galaxies. We use cosmological galaxy formation simulations in Cold Dark Matter (CDM) and Warm Dark Matter (WDM) models to explore how the dark matter model influences the spatial, kinematic, and orbital properties of ESCs. These reveal that the spherically averaged stellar mass density at large galacto-centric radius can be depressed by up to a factor of 10 in WDM models relative to the CDM model, reflecting the anticipated suppressed abundance of satellite galaxies in WDM models. However, these differences are much smaller in WDM models that are compatible with observational limits, and are comparable in size to the system-to-system variation we find within the CDM model. This suggests that it will be challenging to place limits on dark matter using only the unresolved ESC.

  12. What can the outskirts of galaxies tell us about dark matter?

    Science.gov (United States)

    Power, Chris

    2017-03-01

    Deep observations of galaxy outskirts reveal faint extended stellar components (ESCs) of streams, shells, and halos, which are ghostly remnants of the tidal disruption of satellite galaxies. We use cosmological galaxy formation simulations in Cold Dark Matter (CDM) and Warm Dark Matter (WDM) models to explore how the dark matter model influences the spatial, kinematic, and orbital properties of ESCs. These reveal that the spherically averaged stellar mass density at large galacto-centric radius can be depressed by up to a factor of ~10 in WDM models relative to the CDM model, reflecting the anticipated suppressed abundance of satellite galaxies in WDM models. However, these differences are much smaller in WDM models that are compatible with observational limits, and are comparable in size to the system-to-system variation we find within the CDM model. This suggests that it will be challenging to place limits on dark matter using only the unresolved ESC.

  13. A Routing Algorithm in WDM Mesh Networks with Grooming Capacities

    Institute of Scientific and Technical Information of China (English)

    WANG Qiang-min; RONG Meng-tian; ZHU Hong-wen

    2005-01-01

    Most of the work in traffic grooming has been in the area of providing efficient network designs in Wavelength division multiplexing (WDM). The objective of these traffic grooming algorithms is to reduce the cost of overall networks.In this paper, a routing algorithm based on transiently chaotic neural network is proposed to solve the problem in WDM logical topology. The objectives of the routing algorithm are accommodating all traffic requirements and using less network resource. The simulation shows that the proposed algorithm is efficient in the routing selection, meanwhile the algorithm can use less network resource.

  14. Routing and wavelength assignment in hierarchical WDM networks

    Institute of Scientific and Technical Information of China (English)

    Yiyi LU; Ruxiang JIN; Chen HE

    2008-01-01

    A new routing and wavelength assignment method applied in hierarchical wavelength division multiplexing(WDM)networks is proposed.The algorithm is called offiine band priority algorithm(offiine BPA).The offline BPA targets to maximize the number of waveband paths under the condition of minimum number of wavelengths,and solve the routing and wavelength assignment(RWA)problem with waveband grooming to reduce cost.Based on the circle construction algorithm,waveband priority function is introduced to calculate the RWA problem.Simulation results demonstrate that the proposed algorithm achieves significant cost reduction in WDM network construction.

  15. Multicasting in a WDM-upgraded Resilient Packet Ring

    Science.gov (United States)

    Scheutzow, Michael; Seeling, Patrick; Maier, Martin; Reisslein, Martin

    2007-05-01

    The recently approved IEEE 802.17 Resilient Packet Ring (RPR) network deteriorates under multicast traffic to legacy ring technologies that do not support spatial reuse. We extend our multicast approach with spatial reuse from a currently single-channel RPR to WDM-upgraded multichannel RPR networks, where each node can transmit packets on all wavelengths and receive on one wavelength, and analyze their multicast capacity. Our analysis provides a convenient method for evaluating the multicast and reception capacities of WDM-upgraded RPR networks for a wide range of uniform unicast, multicast, and broadcast traffic scenarios.

  16. Warm dark matter in the galaxies:theoretical and observational progresses. Highlights and conclusions of the chalonge meudon workshop 2011

    CERN Document Server

    de Vega, H J

    2011-01-01

    Warm Dark Matter (WDM) research is progressing fast, the subject is new and WDM essentially works, naturally reproducing the astronomical observations over all scales: small (galactic) and large (cosmological) scales (LambdaWDM). Evidence that Cold Dark Matter (LambdaCDM) and its proposed tailored cures do not work at small scales is staggering. Fedor Bezrukov, Pier-Stefano Corasaniti, Hector J. de Vega, Stefano Ettori, Frederic Hessmann, Ayuki Kamada, Marco Lombardi, Alexander Merle, Christian Moni Bidin, Angelo Nucciotti on behalf of the MARE collaboration, Sinziana Paduroiu, Henri Plana, Norma Sanchez, Patrick Valageas, Shun Zhou present here their highlights of the Workshop. LambdaWDM simulations with keV particles remarkably reproduce the observations, small and large structures and velocity functions. Cored DM halos and WDM are clearly determined from theory and astronomical observations, they naturally produce the observed structures at all scales. keV sterile neutrinos are the leading candidates, they...

  17. Internet Protocol-Hybrid Opto-Electronic Ring Network (IP-HORNET): A Novel Internet Protocol-Over-Wavelength Division Multiplexing (IP-Over-WDM) Multiple-Access Metropolitan Area Network (MAN)

    Science.gov (United States)

    2003-04-01

    Technology, STMicroelectronics. 0020-0255/02/$ - see front matter 2002 Elsevier Science Inc . All rights reserved. PII: S0020 -0255 (02 )00250 -5 233...scheduling algorithms. 2002 Elsevier Science Inc . All rights reserved. Keywords: Scheduling; Unslotted CSMA/CA with backoff; MAC; RS; LQF; DPQ; SPF; WDM

  18. Advanced integrated WDM system for POF communication

    Science.gov (United States)

    Haupt, M.; Fischer, U. H. P.

    2009-01-01

    Polymer Optical Fibres (POFs) show clear advantages compared to copper and glass fibres. In essence, POFs are inexpensive, space-saving and not susceptible to electromagnetic interference. Thus, the usage of POFs have become a reasonable alternative in short distance data communication. Today, POFs are applied in a wide number of applications due to these specific advantages. These applications include automotive communication systems and in-house-networks. State-of-the-art is to transmit data with only one channel over POF, this limits the bandwidth. To solve this problem, an integrated MUX/DEMUX-element for WDM over POF is designed and developed to use multiple channels. This integration leads to low costs, therefore this component is suitable for mass market applications. The fundamental idea is to separate the chromatic parts of the light in its monochromatic components by means of a grating based on an aspheric mirror. Due to the high NA of the POF the setup has to be designed in a 3D-approach. Therefore this setup cannot be compared with the planar solutions available on market, they would result high losses in the 3rd dimension. To achieve a fast and optimized design an optical simulation program is used. Particular attention has to be paid to the design of the POF as a light source in the simulation program and the optimisation of the grating. The following realization of the demultiplexer is planed to be done with injection molding. This technology offers easy and very economical processing. These advantages make this technology first choice for optical components in the low-cost array.

  19. Cosmological Structure Formation in Decaying Dark Matter Models

    CERN Document Server

    Cheng, Dalong; Tang, Jiayu

    2015-01-01

    The standard cold dark matter (CDM) model predicts too many and too dense small structures. We consider an alternative model that the dark matter undergoes two-body decays with cosmological lifetime $\\tau$ into only one type of massive daughters with non-relativistic recoil velocity $V_k$. This decaying dark matter model (DDM) can suppress the structure formation below its free-streaming scale at time scale comparable to $\\tau$. Comparing with warm dark matter (WDM), DDM can better reduce the small structures while being consistent with high redshfit observations. We study the cosmological structure formation in DDM by performing self-consistent N-body simulations and point out that cosmological simulations are necessary to understand the DDM structures especially on non-linear scales. We propose empirical fitting functions for the DDM suppression of the mass function and the mass-concentration relation, which depend on the decay parameters lifetime $\\tau$ and recoil velocity $V_k$, and redshift. The fitting ...

  20. Structure of Dark Matter Halos in Warm Dark Matter models and in models with Long-Lived Charged Massive Particles

    CERN Document Server

    Kamada, Ayuki; Kohri, Kazunori; Takahashi, Tomo

    2013-01-01

    We study the formation of non-linear structures in Warm Dark Matter (WDM) models and in a Long-Lived Charged Massive Particle (CHAMP) model. CHAMPs with a decay lifetime of about 1 yr induce characteristic suppression in the matter power spectrum at subgalactic scales through acoustic oscillations in the thermal background. We explore structure formation in such a model. We also study three WDM models, where the dark matter particles are produced through the following mechanisms: i) WDM particles are produced in the thermal background and then kinematically decoupled; ii) WDM particles are fermions produced by the decay of thermal heavy bosons; and iii) WDM particles are produced by the decay of non-relativistic heavy particles. We show that the linear matter power spectra for the three models are all characterised by the comoving Jeans scale at the matter-radiation equality. Furthermore, we can also describe the linear matter power spectrum for the Long-Lived CHAMP model in terms of a suitably defined charac...

  1. Crosslayer Survivability in Overlay-IP-WDM Networks

    Science.gov (United States)

    Pacharintanakul, Peera

    2010-01-01

    As the Internet moves towards a three-layer architecture consisting of overlay networks on top of the IP network layer on top of WDM-based physical networks, incorporating the interaction between and among network layers is crucial for efficient and effective implementation of survivability. This dissertation has four major foci as follows:…

  2. Survivable Impairment-aware Traffic Grooming in WDM Rings

    NARCIS (Netherlands)

    Beshir, A.; Fernando Kuipers, F.; Orda, A.; Van Mieghem, P.

    Wavelength Division Multiplexing (WDM) optical networks offer a large amount of bandwidth using multiple, but independent wavelength channels (or lightpaths), each operating at several Gb/s. Since the traffic between users is usually only a fraction of the capacity offered by a wavelength, several i

  3. Flexible Transport Network Expansion via Open WDM Interfaces

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Skjoldstrup, Bjarke

    2013-01-01

    This paper presents a successful test-bed implementation of a multi-vendor transport network interconnection via open WDM interfaces. The concept of applying Alien Wavelengths (AWs) for network expansion was successfully illustrated via deployment of multi-domain/multi-vendor end-to-end OTN servi...

  4. 100G WDM Transmission over 100 meter Multimode Fiber

    DEFF Research Database (Denmark)

    Cimoli, Bruno; Estaran Tolosa, Jose Manuel; Rodes Lopez, Guillermo Arturo

    We present a comparative performance analysis for wavelength-grid selection in WDM shortrange multimode-fibers. We study 100Gbps links over OM2, OM3 and OM4 fibers and show it is feasible to reach over 100 m transmission distances....

  5. Temporal Probabilistic Constellation Shaping for WDM Optical Communication Systems

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Forchhammer, Søren

    2016-01-01

    Finite state machine sources transmitting QPSK are studied as input to WDM optical fiber systems with ideal distributed Raman amplification. The probabilities of successive constellation symbols are shaped for nonlinear transmission and gains of around 500km (5-10%) are demonstrated...

  6. Temporal Probabilistic Constellation Shaping for WDM Optical Communication Systems

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Forchhammer, Søren

    2016-01-01

    Finite state machine sources transmitting QPSK are studied as input to WDM optical fiber systems with ideal distributed Raman amplification. The probabilities of successive constellation symbols are shaped for nonlinear transmission and gains of around 500km (5-10%) are demonstrated...

  7. Crosslayer Survivability in Overlay-IP-WDM Networks

    Science.gov (United States)

    Pacharintanakul, Peera

    2010-01-01

    As the Internet moves towards a three-layer architecture consisting of overlay networks on top of the IP network layer on top of WDM-based physical networks, incorporating the interaction between and among network layers is crucial for efficient and effective implementation of survivability. This dissertation has four major foci as follows:…

  8. WDM hybrid microoptical transceiver with Bragg volume grating

    Science.gov (United States)

    Jeřábek, Vitezslav; Armas, Julio; Mareš, David; Prajzler, Václav

    2012-02-01

    The paper presents the design, simulation and construction results of the wavelength division multiplex bidirectional transceiver module (WDM transceiver) for the passive optical network (PON) of a fiber to the home (FTTH) topology network. WDM transceiver uses a microoptical hybrid integration technology with volume holographic Bragg grating triplex filter -VHGT and a collimation lenses imagine system for wavelength multiplexing/ demultiplexing. This transmission type VHGT filter has high diffraction angle, very low insertion loses and optical crosstalk, which guide to very good technical parameters of transceiver module. WDM transceiver has been constructed using system of a four micromodules in the new circle topology. The optical micromodule with VHGT filter and collimation and decollimation lenses, two optoelectronics microwave receiver micromodules for receiving download information (internet and digital TV signals) and optoelectronic transmitter micromodule for transmitting upload information. In the paper is presented the optical analysis of the optical imagine system by ray-transfer matrix. We compute and measure VHGT characteristics such as diffraction angle, diffraction efficiency and diffraction crosstalk of the optical system for 1310, 1490 and 1550 nm wavelength radiation. For the design of optoelectronic receiver micromodule was used the low signal electrical equivalent circuit for the dynamic performance signal analysis. In the paper is presented the planar form WDM transceiver with polymer optical waveguides and two stage interference demultiplexing optical filter as well.

  9. Light-Path Provisioning of the WDM Optical Networks

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Provisioning of the WDM optical networks has been a challenge problem because it involves both the physical topology and the logical topology. In addition, the stochastic effects of the traffic mix must be properly characterized. This paper proposes a generic light-path provisioning model and suggests a solution procedure based on a recent mathematical achievement. A case study is also reported.

  10. On-line survivable routing in WDM networks

    NARCIS (Netherlands)

    Beshir, A.A.; Kuipers, F.A.; Van Mieghem, P.F.A.; Orda, A.

    2009-01-01

    In WDM networks, survivable routing and wavelength assignment (SRWA) involves assigning link-disjoint primary and backup lightpaths. In the on-line SRWA problem, a sequence of requests arrive and each request is either accepted or rejected based only on the input sequence seen so far. For special

  11. On-line Survivable Routing in WDM Networks

    NARCIS (Netherlands)

    Beshir, A.A.; Kuipers, F.A.; Van Mieghem, P.; Orda, A.

    In WDM networks, survivable routing and wavelength assignment (SRWA) involves assigning link-disjoint primary and backup lightpaths. In the on-line SRWA problem, a sequence of requests arrive and each request is either accepted or rejected based only on the input sequence seen so far. For special

  12. Performance Analysis of Hybrid WDM-FSO System under Various Weather Conditions

    Science.gov (United States)

    Robinson, S.; Jasmine, S.

    2016-09-01

    Free Space Optical (FSO) communication is being realized as an effective solution for future accessing networks, offering light passed through air. The performance of FSO system can be primarily degraded by various atmospheric attenuations such as rain, fog, haze and snow. At present, hybridization of Dense Wavelength Division Multiplexing (DWDM) with Coarse Wavelength Division Multiplexing (CWDM) becomes necessary to scale the speed and high bandwidth of the services. In this paper, primarily the attenuation values for different weather conditions are calculated. Then the hybrid WDM-FSO system is proposed, designed and the network parameters such as Bit Error Rate (BER), Quality factor (Q factor) and receiver sensitivity are analyzed with respect to link distance for various weather conditions. For investigation, four CWDM (1,510 nm, 1,530 nm, 1,570 nm and 1,570 nm) channel and eight DWDM channels (1,537.4 nm, 1,538.2 nm, 1,539 nm, 1,539.8 nm, 1,540.6 nm, 1,541.4 nm, 1,542.2 nm and 1,543 nm) are considered whose corresponding channel spacing is 20 nm and 0.8 nm, respectively. In addition, the Erbium Doped Fiber Amplifier (EDFA) is inserted at the receiver end in order to enhance the link distance. The proposed hybrid WDM-FSO system is designed to handle the quality of transmission for 12 users, each at a data rate of 2.5 Gbps along an FSO link distance of about 960 km.

  13. 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.

  14. Strange hadrons and antiprotons as probes of hot and dense nuclear matter in relativistic heavy-ion collisions; Seltsame Hadronen und Antiprotonen als Proben heisser und dichter Kernmaterie in relativistischen Schwerionenkollisionen

    Energy Technology Data Exchange (ETDEWEB)

    Schade, Henry

    2010-09-15

    Strange particles play an important role as probes of relativistic heavy-ion collisions where hot and dense matter is studied. The focus of this thesis is on the production of strange particles within a transport model of Boltzmann-Uehling-Uhlenbeck (BUU) type. Current data of the HADES Collaboration concerning K{sup {+-}} and {phi} spectra provide the appropriate experimental framework. Moreover, the double-strange hyperon {xi}{sup -} is analyzed below the free NN production threshold. Hadron multiplicities, transversemomentum and rapidity spectra are compared with recent experimental data. Further important issues are in-medium mass shifts, the nuclear equation of state as well as the mean field of nucleons. Besides the study of AA collisions a comparison with recent ANKE data regarding the {phi} yield in pA collisions is done. Transparency ratios are determined and primarily investigated for absorption of {phi} mesons by means of the BUU transport code. Thereby, secondary {phi} production channels, isospin asymmetry and detector acceptance are important issues. A systematic analysis is presented for different system sizes. The momentum integrated Boltzmann equations describe dense nuclear matter on a hadronic level appearing in the Big Bang as well as in little bangs, in the context of kinetic off-equilibrium dynamics. This theory is applied to antiprotons and numerically calculated under consideration of various expansion models. Here, the evolution of proton- and antiproton densities till freeze-out is analyzed for ultra-relativistic heavy-ion collisions within a hadrochemic resonance gas model acting as a possible ansatz for solving the ''antiproton puzzle''. Furthermore, baryonic matter and antimatter is investigated in the early universe and the adiabatic path of cosmic matter is sketched in the QCD phase diagram. (orig.)

  15. Warmth Elevating the Depths: Shallower Voids with Warm Dark Matter

    CERN Document Server

    Yang, Lin F; Aragon-Calvo, Miguel A; Silk, Joseph

    2014-01-01

    Warm dark matter (WDM) has been proposed as an alternative to cold dark matter (CDM), to resolve issues such as the apparent lack of satellites around the Milky Way. Even if WDM is not the answer to observational issues, it is essential to constrain the nature of the dark matter. The effect of WDM on haloes has been extensively studied, but the small-scale initial smoothing in WDM also affects the present-day cosmic web and voids. It suppresses the cosmic "sub-web" inside voids, and the formation of both void haloes and subvoids. In N-body simulations run with different assumed WDM masses, we identify voids with the zobov algorithm, and cosmic-web components with the origami algorithm. As dark-matter warmth increases, the initial-conditions smoothing increases, and the number of voids and subvoids is suppressed. Also, void density profiles change, their shapes become flatter inside the void radius, while edges of the voids remain unchanged. Also, filaments and walls become cleaner, as the sub-structures in be...

  16. A Robust Miniature Multi-Function, Dense WDM Demultiplexer/Receiver

    Science.gov (United States)

    2007-11-02

    prototype 3D designs in a new polymer material, with limited success, (2) converted the CalTech design code to run on the San Diego Tera supercomputer...algorithm into the Tera code making large-scale 3D designs feasible, (4) began implementing animated visualizations based on an open source package

  17. All-optical WDM Regeneration of DPSK Signals using Optical Fourier Transformation and Phase Sensitive Amplification

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Kjøller, Niels-Kristian;

    2015-01-01

    We propose a novel all-optical WDM regeneration scheme for DPSK signals based on optical Fourier transformation and phase sensitive amplification. Phase regeneration of a WDM signal consisting of 4x10-Gbit/s phase noise degraded DPSK channels is demonstrated for the first time.......We propose a novel all-optical WDM regeneration scheme for DPSK signals based on optical Fourier transformation and phase sensitive amplification. Phase regeneration of a WDM signal consisting of 4x10-Gbit/s phase noise degraded DPSK channels is demonstrated for the first time....

  18. Architecture and Engineering Issues in Building an IP over WDM Networks

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The technologies of IP over WDM have presently received increasing attention owing to the rapid growth in Internet traffic and the need for next-generation Internet technologies. The challenge now is how to integrate the services of IP over WDM optical networks to take full advantages of WDM technologies and IP technologies, and yield a high-throughput optical platform directly underpinning next generation data networks. This article discusses some of the architecture and technology issues for the design of IP over WDM optical networks.

  19. All-optical ultra-high-speed OFDM to Nyquist-WDM conversion

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Mulvad, Hans Christian Hansen

    2015-01-01

    We propose an all-optical ultra-high-speed OFDM to Nyquist-WDM conversion scheme based on complete OFT. An 8-subcarrier 640 Gbit/s DPSK OFDM super-channel is converted to eight 80-Gbit/s Nyquist-WDM channels with BER <10−9 performance for all channels.......We propose an all-optical ultra-high-speed OFDM to Nyquist-WDM conversion scheme based on complete OFT. An 8-subcarrier 640 Gbit/s DPSK OFDM super-channel is converted to eight 80-Gbit/s Nyquist-WDM channels with BER

  20. WDM Phase-Modulated Millimeter-Wave Fiber Systems

    DEFF Research Database (Denmark)

    Yu, Xianbin; Prince, Kamau; Gibbon, Timothy Braidwood

    2012-01-01

    This chapter presents a computer simulation case study of two typical WDM phase-modulated millimeter-wave systems. The phase-modulated 60 GHz fiber multi-channel transmission systems employ single sideband (SSB) and double sideband subcarrier modulation (DSB-SC) schemes and present one of the lat......This chapter presents a computer simulation case study of two typical WDM phase-modulated millimeter-wave systems. The phase-modulated 60 GHz fiber multi-channel transmission systems employ single sideband (SSB) and double sideband subcarrier modulation (DSB-SC) schemes and present one...... of the latest research efforts in the rapidly emerging Radio-over-Fiber (RoF) application space for in-house access networks....

  1. A SURVEY ON WAVELENGTH DIVISION MULTIPLEXING (WDM NETWORKS

    Directory of Open Access Journals (Sweden)

    G. Ramesh

    2010-03-01

    Full Text Available Communication networks have emerged as a source of empowerment in today’s society. At the global level, the Internet is becoming the backbone of the modern economy. The new generations in developed countries cannot even conceive of a world without broadband access to the Internet. The inability of the current Internet infrastructure to cope with the wide variety and ever growing number of users, emerging networked applications, usage patterns and business models is increasingly being recognized worldwide. The dynamic growth of Internet traffic and its bursty nature requires high transmission rate. With the advances and the progress in Wavelength Division Multiplexing (WDM technology, the amount of raw bandwidth available in fiber links has increased to high magnitude. This paper presents a survey on WDM networks from its development to the current status. Also an analysis on buffer size in optical networks for real time traffic was performed.

  2. Optimal design of virtual topology reconfiguration in WDM optical networks

    Institute of Scientific and Technical Information of China (English)

    Fengqing Liu(刘逢清); Qingji Zeng(曾庆济); Xu Zhu(朱栩); Shilin Xiao(肖石林)

    2003-01-01

    Virtual topology of WDM optical networks is often designed for some specific traffic matrix to get thebest network performance. When traffic demand imposed on WDM optical networks changes, the networkperformance may degrade and even become unacceptable. So virtual topology need to be reconfigured.In previous works, virtual topology is reconfigured to achieve the best network performance, in which alarge number of lightpaths need to be set up or torn down. In this paper, we try to get a tradeoff betweenthe network performance and traffic disruption (or implementing cost). The problem of virtual topologyreconfiguration for changing traffic patterns is formulated as an optimization problem and a mixed integerlinear programming (MILP) algorithm is presented. Numerical results show that a large cost reduction ofreconfiguration can be achieved at the expense of network performance.

  3. WDM Systems and Networks Modeling, Simulation, Design and Engineering

    CERN Document Server

    Ellinas, Georgios; Roudas, Ioannis

    2012-01-01

    WDM Systems and Networks: Modeling, Simulation, Design and Engineering provides readers with the basic skills, concepts, and design techniques used to begin design and engineering of optical communication systems and networks at various layers. The latest semi-analytical system simulation techniques are applied to optical WDM systems and networks, and a review of the various current areas of optical communications is presented. Simulation is mixed with experimental verification and engineering to present the industry as well as state-of-the-art research. This contributed volume is divided into three parts, accommodating different readers interested in various types of networks and applications. The first part of the book presents modeling approaches and simulation tools mainly for the physical layer including transmission effects, devices, subsystems, and systems), whereas the second part features more engineering/design issues for various types of optical systems including ULH, access, and in-building system...

  4. Investigation of EDFA Performance in 8 Channel WDM Transmission System

    OpenAIRE

    Lavrinoviča, I; Poriņš, J

    2015-01-01

    Erbium Doped Fiber Amplifier (EDFA) obtained a wide range of applications in research and commercial applications in optical fiber communication systems. It has been considered as an attractive solution because of several major advantages - low loss optical window of silica based fiber (1525-1565 nm), high energy efficiency (>50 %) and time constant enough to cover modulation noises. However, the presence of amplified spontaneous emission (ASE), the difficulty in implementing a WDM system - t...

  5. Current Issues in Finite-T Density-Functional Theory and Warm-Correlated Matter

    Directory of Open Access Journals (Sweden)

    M. W. C. Dharma-wardana

    2016-03-01

    Full Text Available Finite-temperature density functional theory (DFT has become of topical interest, partly due to the increasing ability to create novel states of warm-correlated matter (WCM.Warm-dense matter (WDM, ultra-fast matter (UFM, and high-energy density matter (HEDM may all be regarded as subclasses of WCM. Strong electron-electron, ion-ion and electron-ion correlation effects and partial degeneracies are found in these systems where the electron temperature Te is comparable to the electron Fermi energy EF. Thus, many electrons are in continuum states which are partially occupied. The ion subsystem may be solid, liquid or plasma, with many states of ionization with ionic charge Zj. Quasi-equilibria with the ion temperature Ti ≠ Te are common. The ion subsystem in WCM can no longer be treated as a passive “external potential”, as is customary in T = 0 DFT dominated by solid-state theory or quantum chemistry. Many basic questions arise in trying to implement DFT for WCM. Hohenberg-Kohn-Mermin theory can be adapted for treating these systems if suitable finite-T exchange-correlation (XC functionals can be constructed. They are functionals of both the one-body electron density ne and the one-body ion densities ρj. Here, j counts many species of nuclei or charge states. A method of approximately but accurately mapping the quantum electrons to a classical Coulomb gas enables one to treat electron-ion systems entirely classically at any temperature and arbitrary spin polarization, using exchange-correlation effects calculated in situ, directly from the pair-distribution functions. This eliminates the need for any XC-functionals. This classical map has been used to calculate the equation of state of WDM systems, and construct a finite-T XC functional that is found to be in close agreement with recent quantum path-integral simulation data. In this review, current developments and concerns in finite-T DFT, especially in the context of non-relativistic warm-dense

  6. Performance Evaluation of SCM-WDM System Using Different Linecoding

    CERN Document Server

    Reza, Md Shamim; Chowdhury, Adnan Ahmed; Reza, S M Shamim; Rahman, Md Moshiur

    2010-01-01

    This paper investigates the theoretical performance analysis for a subcarrier multiplexed (SCM) wavelength division multiplexing (WDM) optical transmission system in presence of optical beat interference (OBI) which occurs during the photo detection process. We have presented a comparison for improving the performance of SCM-WDM system in presence of OBI. Non-return-to zero (NRZ), Manchester and Miller code (MC) line coding are used for performance investigation of SCM-WDM system. A suitable signal bandwidth is selected and 200 KHz is considered as channel bandwidth. Power spectrum of signal and cross component for those line coding are analyzed. Comparison results are evaluated in terms of signal to OBI ratio for the three linecoding schemes which is called signal to interference ratio (SIR). It is found that there is a significant increase in the SIR by employing Miller code compared to NRZ and Manchester for the same data rate. For example, for a number of subcarriers of 10, the achievable SIR is about -24...

  7. "Phase freezeout" in isentropically expanding matter

    CERN Document Server

    Iosilevskiy, Igor

    2014-01-01

    Features of isentropic expansion of warm dense matter (WDM) created by intense energy fluxes (strong shock compression or instant isochoric heating by laser or heavy ions) are under discussion in situation when ($i$) -- thermodynamic trajectory of such expansion crosses binodal of liquid-gas phase transition, and ($ii$) -- expansion within the two-phase region is going along equilibrium branch (not metastable one) of the two-phase mixture isentrope. It is known in the plane case that because of break in the expansion isentrope at binodal point (in $P-V$ plane) i.e. jump of sound velocity in this point, there appears extended zone ("boiling layer") of uniformity in expanding material with constant thermodynamic and kinematic parameters. It corresponds just to the state on this binodal of boiling liquid. The point is that because of self-similarity of such expansion (in plane case) this boiling layer contains finite and fixed part of whole expanding material. This property makes it possible (at least formally) ...

  8. Integration of GaAs-based VCSEL array on SiN platform with HCG reflectors for WDM applications

    Science.gov (United States)

    Kumari, Sulakshna; Gustavsson, Johan S.; Wang, Ruijun; Haglund, Emanuel P.; Westbergh, Petter; Sanchez, Dorian; Haglund, Erik; Haglund, Åsa; Bengtsson, Jörgen; Le Thomas, Nicolas; Roelkens, Gunther; Larsson, Anders; Baets, Roel

    2015-02-01

    We present a GaAs-based VCSEL structure, BCB bonded to a Si3N4 waveguide circuit, where one DBR is substituted by a free-standing Si3N4 high-contrast-grating (HCG) reflector realized in the Si3N4 waveguide layer. This design enables solutions for on-chip spectroscopic sensing, and the dense integration of 850-nm WDM data communication transmitters where individual channel wavelengths are set by varying the HCG parameters. RCWA shows that a 300nm-thick Si3N4 HCG with 800nm period and 40% duty cycle reflects strongly (HCG's influence on the VCSEL wavelength, allowing for a 15-nm-wide wavelength setting range with low threshold gain (<1000 cm-1).

  9. Terabit Superchannel Transmission: A Nyquist-WDM Approach%Terabit Superchannel Transmission: A Nyquist-WDM Approach

    Institute of Scientific and Technical Information of China (English)

    Hung-Chang Chien; Jianjun Yu; Zhensheng Jia; Ze Dong

    2012-01-01

    In this work, we focus on enhancing the network reach in terabit superchannel transmission by using a noise-suppressed Nyquist wavelength division multiplexing (NS-N-WDM) technique for polarization multiplexing quadrature phase-shift keying (PM-QPSK) subchannels at different symbol-rate-to-subchannel-spacing ratios up to 1.28. For the first time, we experimentally compare the transmission reach of this emerging technique with that of no-guard-interval coherent optical orthogonal frequency-division multiplexing (NGI-CO-OFDM) on the same testbed. At BER of 2 x 10 3 and 100 Gbit/s per channel, an NGI-CO-OFDM terabit superchannel can transmit over a maximum of 3200 km SMF-28 with EDFA-only amplification, and an NS-N-WDM terabit superchannel can transmit over a maximum of 2800 km SMF-28 with EDFA-only amplification. Assuming different coding gain, 11 x 112 Gbit/s per channel with hard-decision (HD) forward-error correction (FEC) and 11 × 128 Gbit/s per channel NS-N-WDM transmission with soft-decision (SD) FEC can be achieved over a maximum of 2100 km and 2170 km, respectively. These are almost equal and were achieved using digital noise filtering and one-bit maximum likelihood sequence estimation (MLSE) at the receiver DSP. Characteristics including the back-to-back (BTB) curves, the ADC bandwidth requirement, and the tolerance to unequal subchannel power of an NS-N-WDM superchannel were also evaluated.

  10. Dense Axion Stars

    CERN Document Server

    Braaten, Eric; Zhang, Hong

    2015-01-01

    If the dark matter consists of axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound Bose-Einstein condensates of axions. In the previously known axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure.If the axion mass energy is $mc^2= 10^{-4}$ eV, these dilute axion stars have a maximum mass of about $10^{-14} M_\\odot$. We point out that there are also dense axion stars in which gravity is balanced by the mean-field pressure of the axion condensate. We study axion stars using the leading term in a systematically improvable approximation to the effective potential of the nonrelativistic effective field theory for axions. Using the Thomas-Fermi approximation in which the kinetic pressure is neglected, we find a sequence of new branches of axion stars in which gravity is balanced by the mean-field interaction energy of the axion condensate. If $mc^2 = 10^{-4}$ eV, the first branch of these dense axion stars has mas...

  11. Dense Axion Stars

    Science.gov (United States)

    Braaten, Eric; Mohapatra, Abhishek; Zhang, Hong

    2016-09-01

    If the dark matter particles are axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound systems of axions. In the previously known solutions for axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure. The mass of these dilute axion stars cannot exceed a critical mass, which is about 10-14M⊙ if the axion mass is 10-4 eV . We study axion stars using a simple approximation to the effective potential of the nonrelativistic effective field theory for axions. We find a new branch of dense axion stars in which gravity is balanced by the mean-field pressure of the axion Bose-Einstein condensate. The mass on this branch ranges from about 10-20M⊙ to about M⊙ . If a dilute axion star with the critical mass accretes additional axions and collapses, it could produce a bosenova, leaving a dense axion star as the remnant.

  12. Dense Axion Stars

    Science.gov (United States)

    Mohapatra, Abhishek; Braaten, Eric; Zhang, Hong

    2016-03-01

    If the dark matter consists of axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound Bose-Einstein condensates of axions. In the previously known axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure. If the axion mass energy is mc2 =10-4 eV, these dilute axion stars have a maximum mass of about 10-14M⊙ . We point out that there are also dense axion stars in which gravity is balanced by the mean-field pressure of the axion condensate. We study axion stars using the leading term in a systematically improvable approximation to the effective potential of the nonrelativistic effective field theory for axions. Using the Thomas-Fermi approximation in which the kinetic pressure is neglected, we find a sequence of new branches of axion stars in which gravity is balanced by the mean-field interaction energy of the axion condensate. If mc2 =10-4 4 eV, the first branch of these dense axion stars has mass ranging from about 10-11M⊙ toabout M⊙.

  13. The properties of warm dark matter haloes

    Science.gov (United States)

    Lovell, Mark R.; Frenk, Carlos S.; Eke, Vincent R.; Jenkins, Adrian; Gao, Liang; Theuns, Tom

    2014-03-01

    Well-motivated elementary particle candidates for the dark matter, such as the sterile neutrino, behave as warm dark matter (WDM). For particle masses of the order of a keV, free streaming produces a cutoff in the linear fluctuation power spectrum at a scale corresponding to dwarf galaxies. We investigate the abundance and structure of WDM haloes and subhaloes on these scales using high resolution cosmological N-body simulations of galactic haloes of mass similar to the Milky Way's. On scales larger than the free-streaming cutoff, the initial conditions have the same power spectrum and phases as one of the cold dark matter (CDM) haloes previously simulated by Springel et al. as part of the Virgo consortium Aquarius project. We have simulated four haloes with WDM particle masses in the range 1.5-2.3 keV and, for one case, we have carried out further simulations at varying resolution. N-body simulations in which the power spectrum cutoff is resolved are known to undergo artificial fragmentation in filaments producing spurious clumps which, for small masses (Frenk-White or Einasto profiles. Their central densities are lower for lower WDM particle masses and none of the models we have considered suffering from the `too big to fail' problem recently highlighted by Boylan-Kolchin et al.

  14. A robust optical phase modulated 60 GHz RoF WDM system

    DEFF Research Database (Denmark)

    Yu, Xianbin; Kozuch, Wojciech; Turkiewicz, Jaroslaw

    2010-01-01

    robust 4-channel WDM optical phase modulated 60GHz wireless fiber system is proposed and simulated. In this system, a Fabry-Perot (FP) frequency interleaver is designed to suppress optical carriers for 60GHz signal generation. The simulated results show that this phase modulated WDM system...

  15. Analysis of IPACT network performance considering channel switch latency for WDM-EPON

    Institute of Scientific and Technical Information of China (English)

    Zhao Zhou; Shilin Xiao; Min Zhu; Meihua Bi

    2011-01-01

    @@ In wavelength-division multiplexing (WDM) ethernet passive optical networks (EPONs), to realize the statistical multiplexing of upstream wavelength resources, some optical tunable components are introduced in the optical network units.However, the switch latency (SL) of these tunable components constrains the performance of WDM-EPON.In this letter, we extend the mathematical model of the WDM interleaved polling with adaptive cycle time (IPACT) scheme by additionally considering the SL conditions.We also investigate the effect of channel SL on network performance.The simulation results show that the performance of WDM-IPACT-SL deteriorates as the SL increases.%In wavelength-division multiplexing (WDM) ethernet passive optical networks (EPONs), to realize the statistical multiplexing of upstream wavelength resources, some optical tunable components are introduced in the optical network units. However, the switch latency (SL) of these tunable components constrains the performance of WDM-EPON. In this letter, we extend the mathematical model of the WDM interleaved polling with adaptive cycle time (IPACT) scheme by additionally considering the SL conditions. We also investigate the effect of channel SL on network performance. The simulation results show that the performance of WDM-IPACT-SL deteriorates as the SL increases.

  16. Default Path and Dedicated Path: A New Approach to Realize IP Directly Over WDM

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Combining IP and WDM is an attractive direction for research. Instead the point to point linking method, this paper proposes a new approach to realize IP directly over WDM, called DPDP (default path and dedicated path), presents a conceivable architecture in detail and explains its working procedure. A lot of problems related with this design are also discussed.

  17. Holographic Renormalization in Dense Medium

    Directory of Open Access Journals (Sweden)

    Chanyong Park

    2014-01-01

    describes a dense medium at finite temperature, is investigated in this paper. In a dense medium, two different thermodynamic descriptions are possible due to an additional conserved charge. These two different thermodynamic ensembles are classified by the asymptotic boundary condition of the bulk gauge field. It is also shown that in the holographic renormalization regularity of all bulk fields can reproduce consistent thermodynamic quantities and that the Bekenstein-Hawking entropy is nothing but the renormalized thermal entropy of the dual field theory. Furthermore, we find that the Reissner-Nordström AdS black brane is dual to a theory with conformal matter as expected, whereas a charged black brane with a nontrivial dilaton profile is mapped to a theory with nonconformal matter although its leading asymptotic geometry still remains as AdS space.

  18. Electron and ion dynamics study of iron in warm dense matter regime by time-resolved XAS measurements and from first-principles

    Science.gov (United States)

    Ogitsu, T.; Fernandez-Paãella, A.; Correa, A.; Engelhorn, K.; Barbrel, B.; Prendergast, D. G.; Pemmaraju, D.; Beckwith, M.; Kraus, D.; Hamel, S.; Cho, B. I.; Jin, L.; Wong, J.; Heinman, P.; Collins, G. W.; Falcone, R.; Ping, Y.

    2016-10-01

    We present a study of the electron-phonon coupling of warm dense iron upon femtosecond laser excitation by time-resolved x-ray absorption near edge spectroscopy (XANES). The dynamics of iron in electron-ion non-equilibrium conditions was studied using ab-initio density-functional-theory (DFT) simulations combined with the Two Temperature Model (TTM) where spatial inhomogeneity of electron (and ion) temperature(s) due to short ballistic electron transport length in iron was explicitly taken into consideration. Detailed comparison between our simulation results and experiments indicates that the ion temperature dependence on specific heat and on electron-phonon coupling also plays a relevant role in modeling the relaxation dynamics of electrons and ions. These results are the first experimental evidence of the suppression of the electron-phonon coupling factor of a transition metal at electron temperatures ranging 5000- 10000 K. This work was performed under DOE contract DE-AC52-07NA27344 with support from OFES Early Career program and LLNL LDRD program.

  19. Final Technical Report for Years 1-4 of the Early Career Research Project "Viscosity and equation of state of hot and dense QCD matter" - ARRA portion

    Energy Technology Data Exchange (ETDEWEB)

    Molnar, Denes [Purdue Univ., West Lafayette, IN (United States)

    2014-04-14

    The Section below summarizes research activities and achievements during the first four years of the PI’s Early Career Research Project (ECRP). Two main areas have been advanced: i) radiative 3 ↔ 2 radiative transport, via development of a new computer code MPC/Grid that solves the Boltzmann transport equation in full 6+1D (3X+3V+time) on both single-CPU and parallel computers; ii) development of a self-consistent framework to convert viscous fluids to particles, and application of this framework to relativistic heavy-ion collisions, in particular, determination of the shear viscosity. Year 5 of the ECRP is under a separate award number, and therefore it has its own report document ’Final Technical Report for Year 5 of the Early Career Research Project “Viscosity and equation of state of hot and dense QCDmatter”’ (award DE-SC0008028). The PI’s group was also part of the DOE JET Topical Collaboration, a multi-institution project that overlapped in time significantly with the ECRP. Purdue achievements as part of the JET Topical Collaboration are in a separate report “Final Technical Report summarizing Purdue research activities as part of the DOE JET Topical Collaboration” (award DE-SC0004077).

  20. A novel evolution to remodulated WDM-PON based on DPSK/ASK orthogonal modulation

    Science.gov (United States)

    Zhou, Qirui; Ma, Jun; Lu, Yang; Huang, Lingchen; Chen, Biao

    2014-09-01

    A novel evolution scheme from legacy TDM-PON to the next generation WDM-PON with DPSK/ASK orthogonal modulation is proposed. The new WDM-PON is added into the existing PON infrastructure and coexisting with the current TDM-PON. To eliminate any change requirement for the existing TDM-PON, DPSK is applied for WDM-PON downstream. Meanwhile, upstream remodualtion is applied to achieve colorless ONU in WDM-PON. The application of DPSK/ASK reduces both crosstalk from coexisting and remodulation. The experiment results show the crosstalk is very little. Good performance is achieved for both unchanged coexisting TDM-PON and WDM-PON upstream signals in our proposed scheme.

  1. 10Gb/s symmetric WDM-PON realization with colorless ONUs%基于无色ONU的10Gb/s对称WDM-PON实现

    Institute of Scientific and Technical Information of China (English)

    杨晓斐; 李新

    2012-01-01

    提出一个使用无色ONU的上下行对称速率WDM-PON系统解决方案,构建一个包含16个无色ONU的WDM-PON实验系统,其中每个ONU可实现10Gb/s的上下行对称传输速率.仿真实验表明当串扰信号位于相对较高频带时,系统的道际串音容限可以得到很大程度的提高.%A symmetric WDM-PON scheme with colorless ONU is proposed,a WDM-PON system with 16 colorless ONUs is established, and l0Gb/s symmetric transmission for each ONU is realized. Experiment shows that the system tolerance to the intrachannel crosstalk is greatly improved when the crosstalk signal locates at relatively higher frequency band.

  2. Resolving the Large Scale Spectral Variability of the Luminous Seyfert 1 Galaxy 1H 0419-577: Evidence for a New Emission Component and Absorption by Cold Dense Matter

    Science.gov (United States)

    Pounds, K. A.; Reeves, J. N.; Page, K. L.; OBrien, P. T.

    2004-01-01

    An XMM-Newton observation of the luminous Seyfert 1 galaxy 1H 0419-577 in September 2002, when the source was in an extreme low-flux state, found a very hard X-ray spectrum at 1-10 keV with a strong soft excess below -1 keV. Comparison with an earlier XMM-Newton observation when 1H 0419-577 was X-ray bright indicated the dominant spectral variability was due to a steep power law or cool Comptonised thermal emission. Four further XMM-Newton observations, with 1H 0419-577 in intermediate flux states, now support that conclusion, while we also find the variable emission component in intermediate state difference spectra to be strongly modified by absorption in low ionisation matter. The variable soft excess then appears to be an artefact of absorption of the underlying continuum while the core soft emission can be attributed to re- combination in an extended region of more highly ionised gas. We note the wider implications of finding substantial cold dense matter overlying (or embedded in) the X-ray continuum source in a luminous Seyfert 1 galaxy.

  3. Resolving the large scale spectral variability of the luminous Seyfert 1 galaxy 1H 0419-577: Evidence for a new emission component and absorption by cold dense matter

    CERN Document Server

    Pounds, K A; Page, K L; O'Brien, P T

    2004-01-01

    An XMM-Newton observation of the luminous Seyfert 1 galaxy 1H 0419-577 in September 2002, when the source was in an extreme low-flux state, found a very hard X-ray spectrum at 1-10 keV with a strong soft excess below ~1 keV. Comparison with an earlier XMM-Newton observation when 1H 0419-577 was `X-ray bright' indicated the dominant spectral variability was due to a steep power law or cool Comptonised thermal emission. Four further XMM-Newton observations, with 1H 0419-577 in intermediate flux states, now support that conclusion, while we also find the variable emission component in intermediate state difference spectra to be strongly modified by absorption in low ionisation matter. The variable `soft excess' then appears to be an artefact of absorption of the underlying continuum while the `core' soft emission can be attributed to recombination in an extended region of more highly ionised gas. We note the wider implications of finding substantial cold dense matter overlying (or embedded in) the X-ray continuu...

  4. Feasibility analysis of WDM links for radar applications

    Directory of Open Access Journals (Sweden)

    D. Meena

    2015-03-01

    Full Text Available Active phased array antennas enhances the performance of modern radars by using multiple low power transmit/receive modules in place of a high power transmitter in conventional radars. Fully distributed phased array radars demand the distribution of various signals in radio frequency (RF and digital domain for real time operation. This is normally achieved through complex and bulky coaxial distribution networks. In this work, we intend to tap the inherent advantages of fiber links with wavelength division multiplexed (WDM technology and a feasibility study to adapt these links for radar applications is carried out. This is done by analysing various parameters like amplitude, delay, frequency and phase variation response of various radar waveforms over WDM links. This also includes performance evaluation of non-linear frequency modulation (NLFM signals, known for better signal to noise ratio (SNR to specific side lobe levels. NLFM waveforms are further analysed using pulse compression (PC technique. Link evaluation is also carried out using a standard simulation environment and is then experimentally verified with other waveforms like RF continuous wave (CW, pulsed RF and digital signals. Synchronization signals are generated from this variable duty cycle digital signals during real time radar operation. During evaluation of digital signals, variable transient effects for different duty cycles are observed from an amplifier configuration. A suppression method is proposed to eliminate this transient effects. Further, the link delay response is investigated using different lengths of fiber spools. It can be inferred from the experimental results that WDM links are capable of handling various signals significant to radar applications.

  5. Final Technical Report for Year 5 Early Career Research Project "Viscosity and equation of state of hot and dense QCD matter"

    Energy Technology Data Exchange (ETDEWEB)

    Molnar, Denes [Purdue Univ., West Lafayette, IN (United States)

    2016-05-25

    The Section below summarizes research activities and achievements during the fifth (last) year of the PI’s Early Career Research Project (ECRP). Unlike the first four years of the project, the last year was not funded under the American Recovery and Reinvestment Act (ARRA). The ECRP advanced two main areas: i) radiative 3 ↔ 2 radiative transport, via development of a new computer code MPC/Grid that solves the Boltzmann transport equation in full 6+1D (3X+3V+time); and ii) application of relativistic hydrodynamics, via development of a self-consistent framework to convert viscous fluids to particles. In Year 5 we finalized thermalization studies with radiative gg ↔ ggg transport (Sec. 1.1.1) and used nonlinear covariant transport to assess the accuracy of fluid-to-particle conversion models (Sec. 1.1.2), calculated observables with self-consistent fluid-to-particle conversion from realistic viscous hydrodynamic evolution (Secs. 1.2.1 and 1.2.2), extended the covariant energy loss formulation to heavy quarks (Sec. 1.4.1) and studied energy loss in small systems (Sec. 1.4.2), and also investigated how much of the elliptic flow could have non-hydrodynamic origin (Sec 1.3). Years 1-4 of the ECRP were ARRA-funded and, therefore, they have their own report document ’Final Technical Report for Years 1-4 of the Early Career Research Project “Viscosity and equation of state of hot and dense QCD matter”’ (same award number DE-SC0004035). The PI’s group was also part of the DOE JET Topical Collaboration, a multi-institution project that overlapped in time significantly with the ECRP. Purdue achievements as part of the JET Top- ical Collaboration are in a separate report “Final Technical Report summarizing Purdue research activities as part of the DOE JET Topical Collaboration” (award DE-SC0004077).

  6. WDM module research within the Canadian Solid State Optoelectronics Consortium

    Science.gov (United States)

    Fallahi, Mahmoud; Koteles, Emil S.; Delage, Andre; Chatenoud, F.; Templeton, Ian M.; Champion, Garth; He, Jian Jun; Wang, Weijian; Dion, Michael M.; Barber, Richard A.

    1995-02-01

    We report on the design, growth, fabrication, and characterization of monolithic wavelength division multiplexed (WDM) modules produced within the Canadian Solid State Optoelectronics Consortium. The transmitter module includes multiple, discrete wavelength, distributed Bragg reflector (DBR) laser diodes monolithically integrated with waveguide combiners fabricated using an InGaAs/GaAs heterostructure. The wavelength demultiplexer unit is based on a Rowland circle grating spectrometer monolithically integrated with a metal- semiconductor-metal (MSM) detector array fabricated on an InGaAs/AlGaAs/GaAs heterostructure. The epitaxial layer wafers for both transmitter and receiver modules were grown in single molecular beam epitaxy (MBE) runs.

  7. The First Billion Years of a Warm Dark Matter Universe

    CERN Document Server

    Maio, Umberto

    2014-01-01

    We present results of cosmological N-body hydrodynamic chemistry simulations of primordial structure growth and evolution in a scenario with warm dark matter (WDM) having a mass of 3keV and compare with a model consisting of standard cold dark matter (CDM). We focus on the high-redshift universe ($z>6$), where the structure formation process should better reflect the primordial (linear) differences in terms of matter power spectrum. We find that early epochs are exceptional probes of the dark-matter nature. Non-linear CDM and WDM power spectra differ by up to 2 dex at early times and show spreads of factor of a few persisting in the whole first Gyr. Primordial WDM objects with masses $\\lesssim 10^8\\,\\rm M_\\odot$ are less abundant by $\\gtrsim 1\\,\\rm dex$, both in terms of dark matter and of baryon content. Runaway molecular cooling in primordial WDM mini-haloes results severely inhibited due to the damping of power at large $k$ modes. As a consequence, the cosmic (population III and II-I) star formation activi...

  8. Spectrum slicing WDM for FSO communication systems under the heavy rain weather

    Science.gov (United States)

    Rashidi, Florence; He, Jing; Chen, Lin

    2017-03-01

    In the paper, the spectrum sliced wavelength division multiplexed (SS-WDM) is proposed for Free Space Optic (FSO) communication in the heavy rain weather of Changsha, China. The study seeks to investigate the possibility of communication links up to 3 km with 1.56 Gb/s data rate on the wavelength of 1550 nm. A WDM-Demux is used to operate as slicing system. The SS-WDM-FSO system has been realized and investigated for 4 channels with data rate up to 1.56 Gb/s using a continue wave (CW) laser source with and without SS technique. The simulation results show that, using the SS-WDM technique, a data rate of 1.56 Gb/s is achieved over a transmission distance of 2.5 km with the bit error ratio of nearly 9.816×10-11 and the power of 0 dBm. Meanwhile transmitting over FSO channel using WDM without spectrum slicing, the sampled data rate is achieved over a transmission distance of 2.5 km with the BER of 10-3 on power supply of 10 dBm. In addition, the proposed SS-WDM scheme can improve the FSO communication system performance compared to WDM-FSO scheme. Also, its adaptive and scalable network architecture support high bandwidth and wide coverage area over the heavy rain weather, without power penalty.

  9. Study on New Concatenated Code in WDM Optical Transmission Systems

    Institute of Scientific and Technical Information of China (English)

    YUAN Jian-guo; JIANG Ze; MAO You-ju; YE Wen-wei

    2007-01-01

    A new concatenated code of RS(255,239)+BCH(2 040,1 930) code to be suitable for WDM optical transmission systems is proposed.The simulation results show that this new concatenated code,compared with the RS(255,239)+CSOC(k0/n0=6/7,J=8) code in ITU-T G.75.1,has a lower redundancy and better error-correction performance,furthermore,its net coding gain(NCG) is respectively 0.46 dB,0.43 dB more than that of RS(255,239)+CSOC(k0/n0 =6/7,J=8) code and BCH(3 860,3 824)+BCH(2 040,1 930) code in ITU-T G.75.1 at the third iteration for the bit error rate(BER) of 10-12.Therefore,the new super forward error correction(Super-FEC) concatenated code can be better used in ultra long-haul,ultra large-capacity and ultra high-speed WDM optical communication systems.

  10. Digital non-linear equalization for flexible capacity ultradense WDM channels for metro core networking.

    Science.gov (United States)

    Arlunno, Valeria; Zhang, Xu; Larsen, Knud J; Zibar, Darko; Monroy, Idelfonso Tafur

    2011-12-12

    An experimental demonstration of Ultradense WDM with advanced digital signal processing is presented. The scheme proposed allows the use of independent tunable DFB lasers spaced at 12.5 GHz for ultradense WDM PM-QPSK flexible capacity channels for metro core networking. To allocate extremely closed carriers, we demonstrate that a digital non-linear equalization allow to mitigate inter-channel interference and improve overall system performance in terms of OSNR. Evaluation of the algorithm and comparison with an ultradense WDM system with coherent carriers generated from a single laser are also reported. © 2011 Optical Society of America

  11. Digital non-linear equalization for flexible capacity ultradense WDM channels for metro core networking

    DEFF Research Database (Denmark)

    Arlunno, Valeria; Zhang, Xu; Larsen, Knud J.

    2011-01-01

    An experimental demonstration of Ultradense WDM with advanced digital signal processing is presented. The scheme proposed allows the use of independent tunable DFB lasers spaced at 12.5 GHz for ultradense WDM PM-QPSK flexible capacity channels for metro core networking. To allocate extremely closed...... carriers, we demonstrate that a digital non-linear equalization allow to mitigate inter-channel interference and improve overall system performance in terms of OSNR. Evaluation of the algorithm and comparison with an ultradense WDM system with coherent carriers generated from a single laser are also...

  12. Power consumption comparison between point-to-point WDM and OTDM systems

    DEFF Research Database (Denmark)

    Xu, Jing; Peucheret, Christophe; Jeppesen, Palle

    2010-01-01

    This talk will focus on the power consumption comparison between point-to-point wavelength division multiplexing (WDM) systems and optical time division multiplexing (OTDM) systems. By keeping the structure simple, the advantages and disadvantages of the WDM and OTDM techniques are highlighted from...... an energy efficiency point of view. Our analysis shows that in order to be comparable to WDM systems in power consumption aspect, the topology of the demultiplexing unit in OTDM systems must be carefully chosen and optimized and trade-offs have to be made between speed and power consumption using state...

  13. Dense topological spaces and dense continuity

    Science.gov (United States)

    Aldwoah, Khaled A.

    2013-09-01

    There are several attempts to generalize (or "widen") the concept of topological space. This paper uses equivalence relations to generalize the concept of topological space via the concept of equivalence relations. By the generalization, we can introduce from particular topology on a nonempty set X many new topologies, we call anyone of these new topologies a dense topology. In addition, we formulate some simple properties of dense topologies and study suitable generalizations of the concepts of limit points, closeness and continuity, as well as Jackson, Nörlund and Hahn dense topologies.

  14. Lyman-{\\alpha} Forest and Cosmic Weak Lensing in a Warm Dark Matter Universe

    CERN Document Server

    Markovič, Katarina

    2013-01-01

    We review the current state of the theory of large scale structure in a warm dark matter (WDM) cosmological model. In particular, we focus on the non-linear modelling of the matter power spectrum and on the mass function of dark matter haloes. We describe the results of N-body simulations with WDM and mention the effects that could be induced by baryonic physics. We also examine the halo model of large scale structure and its recently suggested modifications for a WDM cosmology, which account for the small scale smoothness of the initial matter density field and better fit the results of N-body simulations. Having described the theoretical models, we discuss the current lower limits on the WDM particle mass, m_w, which correspond to upper limits on the WDM temperature under the assumption that the particles are thermal relics. The best such constraints come from the Ly{\\alpha} forest and exclude all masses below 3.3 keV at the 2{\\sigma} confidence level. We finally review the forecasts for future lensing surv...

  15. The Extended Stellar Component of Galaxies the Nature of Dark Matter

    Science.gov (United States)

    Power, C.; Robotham, A. S. G.

    2016-07-01

    Deep observations of galaxies reveal faint extended stellar components (hereafter ESCs) of streams, shells, and halos. These are a natural prediction of hierarchical galaxy formation, as accreted satellite galaxies are tidally disrupted by their host. We investigate whether or not global properties of the ESC could be used to test of dark matter, reasoning that they should be sensitive to the abundance of low-mass satellites, and therefore the underlying dark matter model. Using cosmological simulations of galaxy formation in the favored Cold Dark Matter (CDM) and Warm Dark Matter (WDM) models ({m}{{WDM}}=0.5,1,2 {{keV}}/{c}2), which suppress the abundance of low-mass satellites, we find that the kinematics and orbital structure of the ESC is consistent across models. However, we find striking differences in its spatial structure, as anticipated—a factor of ˜10 drop in spherically averaged mass density between ˜10% and ˜75% of the virial radius in the more extreme WDM runs ({m}{{WDM}} = 0.5, 1 {{keV}}/{c}2) relative to the CDM run. These differences are consistent with the mass assembly histories of the different components, and are present across redshifts. However, even the least discrepant of the WDM models is incompatible with current observational limits on {m}{{WDM}}. Importantly, the differences we observe when varying the underlying dark matter are comparable to the galaxy-to-galaxy variation we expect within a fixed dark matter model. This suggests that it will be challenging to place limits on dark matter using only the unresolved spatial structure of the the ESC.

  16. Extended Stellar Components of Galaxies & the Nature of Dark Matter

    CERN Document Server

    Power, Chris

    2016-01-01

    Deep observations of galaxies reveal faint extended stellar components (hereafter ESCs) of streams, shells, and halos. These are a natural prediction of hierarchical galaxy formation, as accreted satellite galaxies are tidally disrupted by their host. We investigate whether or not global properties of the ESC could be used to test of dark matter, reasoning that they should be sensitive to the abundance of low-mass satellites, and therefore the underlying dark matter model. Using cosmological simulations of galaxy formation in the favoured Cold Dark Matter (CDM) and Warm Dark Matter (WDM) models ($m_{\\rm WDM}$=0.5,1,2 keV/$c^2$), which suppress the abundance of low-mass satellites, we find that the kinematics and orbital structure of the ESC is consistent across models. However, we find striking differences in its spatial structure, as anticipated -- a factor of $\\sim$10 drop in spherically averaged mass density between $\\sim$10% and $\\sim$75% of the virial radius in the more extreme WDM runs ($m_{\\rm WDM}$=0....

  17. Constellation Shaping for WDM systems using 256QAM/1024QAM with Probabilistic Optimization

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Da Ros, Francesco; Porto da Silva, Edson;

    2016-01-01

    In this paper, probabilistic shaping is numerically and experimentallyinvestigated for increasing the transmission reach of wavelength divisionmultiplexed (WDM) optical communication system employing quadrature amplitudemodulation (QAM). An optimized probability mass function (PMF) of the QAMsymb...

  18. Transmission Bandwidth Expansion of SI-POF Using WDM-Pulse-Position Modulations

    Institute of Scientific and Technical Information of China (English)

    Katsumi; Takano; Eiji; Matsumoto; Kiyoshi; Nakagawa

    2003-01-01

    WDM-Pulse-position modulation technique in SI-POF transmission is proposed to overcome the limitation from mode dispersion. It can expand the flat transmission bandwidth to 80MHz with 100m-fiber length.

  19. Analysis of a 32-Channal Benes Switching Network Including an SDM/WDM Router

    Institute of Scientific and Technical Information of China (English)

    Shyh-Lin Tsao; Yu-Min Lu; Hsin-Hung Lin

    2003-01-01

    An spatial division multiplexing/wavelength division multiplexing router is designed for applying in a fiber-optical wide area network. Our comparison shows various spans of the good SDM/WDM WAN using the SOA based router.

  20. Analysis of a 32-Channal Benes Switching Network Including an SDM/WDM Router

    Institute of Scientific and Technical Information of China (English)

    Shyh-Lin; Tsao; Hsin-Hung; Lin

    2003-01-01

    An spatial division multiplexing/wavelength division multiplexing router is designed for applying in a fiber-optical wide area network. Our comparison shows various spans of the good SDM/WDM WAN using the SO A based router.

  1. Performance Study on Priority Strategies for WDM Packet Switches under Long-Range Dependent Traffic

    Institute of Scientific and Technical Information of China (English)

    Chia-Wei; Yu; Chao-Chih; Chang; Shou-Kuo; Shao; Jingshown; Wu

    2003-01-01

    The impact of long-range dependent (LRD) traffic on the buffer management schemes for WDM packet switches is studied by simulation. The different priority strategies are compared. The principles of efficient strategy design are also presented.

  2. Performance Optimization of Dispersion-Managed WDM Systems Based on Four-Wave Mixing

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    We systemically investigate the interchannel four-wave mixing (FWM) in dispersion-managed WDM systems with arbitrary launch position. We optimize the number of fiber sections, and the dispersion ratio for the system performance.

  3. SDN-enabled dynamic WDM networks to address routing information inaccuracy

    CSIR Research Space (South Africa)

    Ravhuanzwo, Lusani

    2016-11-01

    Full Text Available International Conference on Advances in Computing, Communication, & Engineering (ICACCE-2016), Coastlands Umhlanga Hotel & Resorts, Durban, 28-29 November 2016 SDN-enabled dynamic WDM networks to address routing information inaccuracy L. Ravhuanzwo, A...

  4. A reconfigurable all-optical VPN based on XGM effect of SOA in WDM PON

    Science.gov (United States)

    Hu, Xiaofeng; Zhang, Liang; Cao, Pan; Wang, Tao; Su, Yikai

    2010-12-01

    We propose and experimentally demonstrate a reconfigurable all-optical VPN scheme enabling intercommunications among different ONUs in a WDM PON. Reconfiguration is realized by dynamically setting wavelength conversion of optical VPN signal using a SOA in the OLT.

  5. Remotely controllable WDM-PON technology for wireless fronthaul/backhaul application

    DEFF Research Database (Denmark)

    Eiselt, Michael H.; Wagner, Christoph; Lawin, Mirko

    2016-01-01

    Low-cost WDM-PON solutions for fronthaul and backhaul applications will include remotely controlled tail-end transceivers. We report on control aspects of these transceivers and how standardization is evolving to enable these applications....

  6. More Than 10 Gbps Photonic Packet-Switched Networks Using WDM-Based Packet Compression

    Institute of Scientific and Technical Information of China (English)

    Hiroaki Harai; Naoya Wada

    2003-01-01

    We propose photonic packet-switched networks in which more than 10Gbps optical packets are transferred. WDM- based packet compression at edge nodes plays an important role in resolving interface gap between core and metro.

  7. All-Optical WDM Buffer System Realized by NOLM and Feedback Loop Structure

    Institute of Scientific and Technical Information of China (English)

    Seungwoo Yi; Kyeong-Mo Yoon; Yong-Gi Lee; Jinseob Eom

    2003-01-01

    We propose an all-optical WDM buffer for optical packet switching system, which consists of NOLM and feedback loop. The proposed structure provides more than 40 turn buffering and nice output of buffered data when selected by control signal.

  8. Colorless ONU Based on All-VCSEL Sources with Remote Optical Injection for WDM-PON

    DEFF Research Database (Denmark)

    Deng, Lei; Zhao, Ying; Pang, Xiaodan;

    2011-01-01

    We propose a novel low-cost and colorless WDM-PON architecture by using all VCSELs-based optical injection locking technique. A bidirectional transmission system over 26 km SMF at 5 Gbps without optical amplification is successfully achieved....

  9. Nonlinear Phase Noise Compensation in Experimental WDM Systems with 256QAM

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Da Ros, Francesco; Porto da Silva, Edson

    2016-01-01

    Nonlinear phase noise (NLPN) is studied in an experimental wavelength division multiplexed (WDM) system operating at 256QAM. Extremely narrow linewidth lasers (phase part of the nonlinear noise in a Raman amplified link. Based...

  10. Colorless ONU Based on All-VCSEL Sources with Remote Optical Injection for WDM-PON

    DEFF Research Database (Denmark)

    Deng, Lei; Zhao, Ying; Pang, Xiaodan

    2011-01-01

    We propose a novel low-cost and colorless WDM-PON architecture by using all VCSELs-based optical injection locking technique. A bidirectional transmission system over 26 km SMF at 5 Gbps without optical amplification is successfully achieved....

  11. Optical fronthauling for 5G mobile: A perspective of passive metro WDM technology

    DEFF Research Database (Denmark)

    Zou, Shihuan Jim; Wagner, Christoph; Eiselt, Michael

    2017-01-01

    We discuss the necessity of passive WDM technology in the 5G fronthaul application. The proof-of-concept field trial showed that the proposed system integrated seamlessly with the current wireless equipment and had no impact on services.......We discuss the necessity of passive WDM technology in the 5G fronthaul application. The proof-of-concept field trial showed that the proposed system integrated seamlessly with the current wireless equipment and had no impact on services....

  12. Fiber-fault protection WDM-PON using new apparatus in optical networking unit

    Science.gov (United States)

    Yeh, C. H.; Chow, C. W.; Shih, F. Y.; Wu, Y. F.; Sung, J. Y.

    2012-04-01

    In this study, we propose and experimentally demonstrate a simple self-protection architecture for WDM passive optical network (PON) by adding a novel 2 × 2 optical switch design in each optical networking unit (ONU). Two adjacent ONUs are interconnected into a group. By using the proposed protection architecture, the affected traffic can be restored immediately against fiber fault in the feeder and distributed fibers. Moreover, the performance of proposed self-protection WDM-PON is also discussed and analyzed.

  13. Compact Wireless Access Nodes for WDM Bidirectional Radio-over-Fiber System Based on RSOA

    DEFF Research Database (Denmark)

    Yu, Xianbin; Gibbon, Timothy Braidwood; Tafur Monroy, Idelfonso

    2009-01-01

    We demonstrate a RSOA based WDM radio-over-fiber, bidirectional system for wireless access networks. The multi-functionalities of a RSOA, such as colorless operation, re-modulation and envelope detection, make wireless access nodes more compact.......We demonstrate a RSOA based WDM radio-over-fiber, bidirectional system for wireless access networks. The multi-functionalities of a RSOA, such as colorless operation, re-modulation and envelope detection, make wireless access nodes more compact....

  14. Digital Non-Linear Equalization for Flexible Capacity Ultradense WDM Channels for Metro Core Networking

    DEFF Research Database (Denmark)

    Arlunno, Valeria; Zhang, Xu; Larsen, Knud J.

    2011-01-01

    We experimentally demonstrate that digital non-linear equalization allows for using independent tunable DFB lasers spaced at 12.5 GHz for ultradense WDM PM-QPSK flexible capacity channels for metro core networking.......We experimentally demonstrate that digital non-linear equalization allows for using independent tunable DFB lasers spaced at 12.5 GHz for ultradense WDM PM-QPSK flexible capacity channels for metro core networking....

  15. Real time algorithm temperature compensation in tunable laser / VCSEL based WDM-PON system

    DEFF Research Database (Denmark)

    Iglesias Olmedo, Miguel; Rodes Lopez, Roberto; Pham, Tien Thang

    2012-01-01

    We report on a real time experimental validation of a centralized algorithm for temperature compensation of tunable laser/VCSEL at ONU and OLT, respectively. Locking to a chosen WDM channel is shown for temperature changes over 40°C.......We report on a real time experimental validation of a centralized algorithm for temperature compensation of tunable laser/VCSEL at ONU and OLT, respectively. Locking to a chosen WDM channel is shown for temperature changes over 40°C....

  16. Comparison of WDM/Pulse-Position-Modulation (WDM/PPM) with Code/Pulse-Position-Swapping (C/PPS) Based on Wavelength/Time Codes

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, A J; Hernandez, V J; Gagliardi, R M; Bennett, C V

    2009-06-19

    Pulse position modulation (PPM) signaling is favored in intensity modulated/direct detection (IM/DD) systems that have average power limitations. Combining PPM with WDM over a fiber link (WDM/PPM) enables multiple accessing and increases the link's throughput. Electronic bandwidth and synchronization advantages are further gained by mapping the time slots of PPM onto a code space, or code/pulse-position-swapping (C/PPS). The property of multiple bits per symbol typical of PPM can be combined with multiple accessing by using wavelength/time [W/T] codes in C/PPS. This paper compares the performance of WDM/PPM and C/PPS for equal wavelengths and bandwidth.

  17. Transmission Experiment of 80-Gbit/s-Based WDM Signals Using an OPGW in the Field and In-service Chromatic Dispersion Monitering through Envelope Modulated WDM Signals

    Science.gov (United States)

    Yamashita, Ikuo; Oro, Kyoichi; Seikai, Shigeyuki

    A field experiment on transmission of 80-Gbit/s-based wavelength division multiplexing (WDM) signals is successfully carried out. In order to keep good transmission quality, technique of an in-service dispersion monitoring and an adaptive control of the chromatic dispersion are proposed. Difference of the propagation delay between channels caused by the chromatic dispersion of the transmission line is detected using signals superimposed on the envelope of the WDM pulses. Dispersion alteration of the transmission line is estimated from the measured delay in real-time. Accuracy of the method is clarified through a transmission experiment using wound fibers in an oven changing their temperature. The field experiment on 80Gbit/s × 8WDM transmission using an OPGW with 60km × 2spans is carried out and fine BER performances are obtained in all channels. Transmission properties are found to be stable owing to the dispersion control techniques throughout the field trial.

  18. Dynamic protected lightpath provisioning in mesh WDM networks

    Institute of Scientific and Technical Information of China (English)

    Guolong Zhu; Qingji Zeng; Tian Xu; Tong Ye; Junjie Yang

    2005-01-01

    This paper investigates the problem of dynamic protected lightpath services provisioning in optical mesh networks employing wavelength division multiplexing (WDM). A variety of schemes for dynamic protected services provisioning have been proposed, supporting a range of tradeoffs among restoration speed, capacity efficiency, and scalability. In this paper, we propose a novel scheme, called p-cycles-based maximum protected working capacity envelope (PC-MPWCE), which can offer an attractive combination of fea-tures: ring-like speed, mesh-like capacity efficiency, and good scalability. To evaluate the performance of PC-MPWCE, we compare it via simulation with 1 + 1 automatic protection switching (APS) and two well-known shared backup path protection (SBPP) on NSFNET. Our simulation results show that PCMPWCE can achieve much better blocking performance than 1 + 1 APS, and perform the similar blocking performance and capacity efficiency as SBPP.

  19. Study of WDM polymer planar curved waveguide couplers

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A wavelength division multiplexer based on curved polymer planar waveguide is proposed. According to the coupled mode theory and the waveguide structure, the performance of the curved waveguide coupler (CWC) is analyzed. The results show that CWC can accommodate wider multiplexing bandwidth than parallel straight waveguide coupler (SWC) due to the compensation effect of the effective coupling length. The two variables, curvature radius and minimum spacing, increase the design flexibility of the waveguide device. A 4-channel wavelength division multiplexing (WDM) system based on CWC is designed. The deviation of the center wavelength, due to the errors of curvature radius and minimum spacing during fabrication process, is investigated. The smaller the curvature radius and the minimum spacing are, the larger the central wavelength deviation caused by the error of the curvature radius and the minimum spacing is, which provides some useful theoretical basis for the design and the fabrication of polymer waveguide devices.

  20. Massive WDM and TDM Soliton Transmission Systems : a ROSC Symposium

    CERN Document Server

    2002-01-01

    This book summarizes the proceedings of the invited talks presented at the “International Symposium on Massive TDM and WDM Optical Soliton Tra- mission Systems” held in Kyoto during November 9–12, 1999. The symposium is the third of the series organized by Research Group for Optical Soliton C- munications (ROSC) chaired by Akira Hasegawa. The research group, ROSC, was established in Japan in April 1995 with a support of the Japanese Ministry of Post and Telecommunications to promote collaboration and information - change among communication service companies, communication industries and academic circles in the theory and application of optical solitons. The symposium attracted enthusiastic response from worldwide researchers in the field of soliton based communications and intensive discussions were made. In the symposium held in 1997, new concept of soliton transmission based on dispersion management of optical fibers were presented. This new soliton is now called the dispersion managed soliton. The p...

  1. Raman Amplification in WDM Optical Communication Systems: A System Perceptive

    Science.gov (United States)

    Raghuwanshi, Sanjeev Kumar; Srinivas, Talabattula

    2016-12-01

    Statistical study on stimulated Raman scattering (SRS) crosstalk has been done by many researchers while ignoring pulse walk-off effect due to analytically unsolvable nonlinear coupled equations. To our knowledge there is no treatise, which deals with pulse walk-off effect except statistically for few cases in case of wideband WDM Raman amplification systems. In this paper, we investigate the effect of group velocity dispersion induced crosstalk. We have tried to solve nonlinear coupled Raman gain equations for few channels by using the numerical technique called finite difference method. Finally we have provided results of the simulation for few cases. It is ever known that pulse walk-off effect (time-dependent effect) is responsible for transient effects hence the modeling has also done in this paper to simulate the effect of abrupt channel addition and removal response.

  2. A Novel Switching Architecture for IP Over WDM Networks

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Integrating IP and WDM is an attractive direction for research.Many solutions have been presented but it is noted that the existing switching technologies still need more concern. Since optical packet switching is not practical yet, there are just two possible solutions left. One is wavelength routing(WR), which is circuit switching in essence and the other is newly proposed optical burst switching (OBS). In this paper, characteristics of WR and OBS are first described, then, compared in several aspects. It is notice that in many aspects, the wavelength routing and burst switching are complement. This stimulates us to propose a new switching architecture, which may be considered as “mixture” of WR and OBS. We beleve the network built on new switching structure can accommodate the requirements of practicability, flexibility, robustness, effciency and etc. simultaneously. However, many related problems still need to be further researched.

  3. FAIRNESS OF SHARING PROTECTION FOR MULTICAST IN WDM NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Li Yonggang; Jin Yaohui; Li Lemin

    2008-01-01

    In this paper,the sharing schemes of multicast in survivable Wavelength-Division Multiplexed (WDM) networks are studied and the concept of Shared Risk Link Group (SRLG) is considered.While the network resources are shared by the backup paths,the sharing way is possible to make the backup paths selfish. This selfishness leads the redundant hops of the backup route and a large number of primary lightpaths to share one backup link. The sharing schemes,especially,the self-sharing and cross-sharing,are investigated to avoid the selfishness when computing the backup light-tree. In order to decrease the selfishness of the backup paths,it is important to make the sharing links fair to be used.There is a trade-off between the self-sharing and cross-sharing,which is adjusted through simulation to adapt the sharing degree of each sharing scheme and save the network resources.

  4. Enhanced nucleic acid amplification with blood in situ by wire-guided droplet manipulation (WDM).

    Science.gov (United States)

    Harshman, Dustin K; Reyes, Roberto; Park, Tu San; You, David J; Song, Jae-Young; Yoon, Jeong-Yeol

    2014-03-15

    There are many challenges facing the use of molecular biology to provide pertinent information in a timely, cost effective manner. Wire-guided droplet manipulation (WDM) is an emerging format for conducting molecular biology with unique characteristics to address these challenges. To demonstrate the use of WDM, an apparatus was designed and assembled to automate polymerase chain reaction (PCR) on a reprogrammable platform. WDM minimizes thermal resistance by convective heat transfer to a constantly moving droplet in direct contact with heated silicone oil. PCR amplification of the GAPDH gene was demonstrated at a speed of 8.67 s/cycle. Conventional PCR was shown to be inhibited by the presence of blood. WDM PCR utilizes molecular partitioning of nucleic acids and other PCR reagents from blood components, within the water-in-oil droplet, to increase PCR reaction efficiency with blood in situ. The ability to amplify nucleic acids in the presence of blood simplifies pre-treatment protocols towards true point-of-care diagnostic use. The 16s rRNA hypervariable regions V3 and V6 were amplified from Klebsiella pneumoniae genomic DNA with blood in situ. The detection limit of WDM PCR was 1 ng/μL or 10(5)genomes/μL with blood in situ. The application of WDM for rapid, automated detection of bacterial DNA from whole blood may have an enormous impact on the clinical diagnosis of infections in bloodstream or chronic wound/ulcer, and patient safety and morbidity.

  5. Research on realization method of colorless ONU in WDM-PON system%WDM-PON无色ONU实现方法研究

    Institute of Scientific and Technical Information of China (English)

    方圆圆; 寿国础; 胡怡红

    2007-01-01

    WDM-PON是一种容量大、易升级、网络安全性高的新一代光接入网技术.文章简要分析了固定波长和可调谐波长的ONU实现方法,指出了其不足;重点研究了采用宽光源技术和无光源技术实现ONU的方法,指出无色ONU是构建WDM-PON的一种较理想的解决方案.

  6. Dense nucleonic matter and the renormalization group

    CERN Document Server

    Drews, Matthias; Klein, Bertram; Weise, Wolfram

    2013-01-01

    Fluctuations are included in a chiral nucleon-meson model within the framework of the functional renormalization group. The model, with parameters fitted to reproduce the nuclear liquid-gas phase transition, is used to study the phase diagram of QCD. We find good agreement with results from chiral effective field theory. Moreover, the results show a separation of the chemical freeze-out line and chiral symmetry restoration at large baryon chemical potentials.

  7. Dense nucleonic matter and the renormalization group

    Directory of Open Access Journals (Sweden)

    Drews Matthias

    2014-03-01

    Full Text Available Fluctuations are included in a chiral nucleon-meson model within the framework of the functional renormalization group. The model, with parameters fitted to reproduce the nuclear liquid-gas phase transition, is used to study the phase diagram of QCD. We find good agreement with results from chiral effective field theory. Moreover, the results show a separation of the chemical freeze-out line and chiral symmetry restoration at large baryon chemical potentials.

  8. Inverse magnetic catalysis in dense holographic matter

    CERN Document Server

    Preis, Florian; Schmitt, Andreas

    2010-01-01

    We study the chiral phase transition in a magnetic field at finite temperature and chemical potential within the Sakai-Sugimoto model, a holographic top-down approach to (large-N_c) QCD. We consider the limit of a small separation of the flavor D8-branes, which corresponds to a dual field theory comparable to a Nambu-Jona Lasinio (NJL) model. Mapping out the surface of the chiral phase transition in the parameter space of magnetic field strength, quark chemical potential, and temperature, we find that for small temperatures the addition of a magnetic field decreases the critical chemical potential for chiral symmetry restoration - in contrast to the case of vanishing chemical potential where, in accordance with the familiar phenomenon of magnetic catalysis, the magnetic field favors the chirally broken phase. This "inverse magnetic catalysis" (IMC) appears to be associated with a previously found magnetic phase transition within the chirally symmetric phase that shows an intriguing similarity to a transition ...

  9. Dense with Sense

    Science.gov (United States)

    Aletras, Anthony H.; Ingkanisorn, W. Patricia; Mancini, Christine; Arai, Andrew E.

    2005-09-01

    Displacement encoding with stimulated echoes (DENSE) with a low encoding strength phase-cycled meta-DENSE readout and a two fold SENSE acceleration ( R = 2) is described. This combination reduces total breath-hold times for increased patient comfort during cardiac regional myocardial contractility studies. Images from phantoms, normal volunteers, and a patient are provided to demonstrate the SENSE-DENSE combination of methods. The overall breath-hold time is halved while preserving strain map quality.

  10. Impact of backreflections on single-fiber bidirectional wavelength-division-multiplexing passive optical networks (WDM-PONs)

    Science.gov (United States)

    Gao, Shiyu

    With increased demand for bandwidth-hungry applications such as video-on-demand, wavelength-division-multiplexing passive optical network (WDM-PON) has become a strong contender in overcoming the last mile bottle neck. However, the wide-scale deployment of WDM-PONs has been delayed mainly due to the high cost of wavelength-specific optical components. To realize cost-effective WDM-PONs, various wavelength-independent, so called colorless architectures, have been developed so that all the subscribers can have identical optical network units (ONUs). In such WDM-PONs, however, single-fiber bidirectional transmission results in degradation of system performance caused by interference between the signals and backreflections. This thesis investigates the impact of backreflections on single-fiber bidirectional WDM-PONs. A WDM-PON with various optical line terminals (OLTs) and colorless ONU configurations is presented. The dependence of the power penalty, caused by backreflections, on a variety of parameters is investigated. This includes parameters such as the source linewidths, receiver bandwidth, transmission line loss (TLL), ONU gain, chirp effect at the ONU and optical return loss (ORL), in various WDM-PON configurations. The WDM-PON with continuous wave (CW) seed light and remodulation schemes are both presented and studied experimentally. The impacts of the backreflections on the single-fiber bidirectional WDM-PON with various OLT and ONU configurations are compared and analyzed accordingly.

  11. Quantum dense key distribution

    CERN Document Server

    Degiovanni, I P; Castelletto, S; Rastello, M L; Bovino, F A; Colla, A M; Castagnoli, G C

    2004-01-01

    This paper proposes a new protocol for quantum dense key distribution. This protocol embeds the benefits of a quantum dense coding and a quantum key distribution and is able to generate shared secret keys four times more efficiently than BB84 one. We hereinafter prove the security of this scheme against individual eavesdropping attacks, and we present preliminary experimental results, showing its feasibility.

  12. The properties of warm dark matter haloes

    CERN Document Server

    Lovell, Mark R; Eke, Vincent R; Jenkins, Adrian; Gao, Liang; Theuns, Tom

    2013-01-01

    Well-motivated elementary particle candidates for the dark matter, such as the sterile neutrino, behave as warm dark matter (WDM).For particle masses of order a keV, free streaming produces a cutoff in the linear fluctuation power spectrum at a scale corresponding to dwarf galaxies. We investigate the abundance and structure of WDM haloes and subhaloes on these scales using high resolution cosmological N-body simulations of galactic haloes of mass similar to the Milky Way's. On scales larger than the free-streaming cutoff, the initial conditions have the same power spectrum and phases as one of the cold dark matter (CDM) haloes previously simulated by Springel et al as part of the Virgo consortium Aquarius project. We have simulated four haloes with WDM particle masses in the range 1.4-2.3keV and, for one case, we have carried out further simulations at varying resolution. N-body simulations in which the power spectrum cutoff is resolved are known to undergo artificial fragmentation in filaments producing spu...

  13. The inner structure of dwarf sized halos in Warm and Cold Dark Matter cosmologies

    CERN Document Server

    Gonzalez-Samaniego, Alejandro; Colin, Pedro

    2015-01-01

    By means of N-body+Hydrodynamics zoom-in simulations we study the evolution of the inner dark matter and stellar mass distributions of central dwarf galaxies formed in halos of virial masses mh=2-3x10^10 Msun at z=0, both in a WDM and CDM cosmology. The half-mode mass in the WDM power spectrum of our simulations is Mv= 2x 10^10 Msun. In the dark matter only simulations halo density profiles are well described by the NFW parametric fit in both cosmologies, though the WDM halos have concentrations lower by factors 1.5--2.0 than their CDM counterparts. In the hydrodynamical simulations, the effects of baryons significantly flatten the inner density, velocity dispersion, and pseudo phase-space density profiles of the WDM halos but not of the CDM ones. The density slope measured at ~ 0.02xRv, alpha, becomes shallow in periods of 2 to 5 Gyr in the WDM runs. We explore whether this flattening process correlates with the global SF, Ms/Mv ratio, gas outflow, and internal specific angular momentum histories. We do not ...

  14. Systems performance comparison of three all-optical generation schemes for quasi-Nyquist WDM.

    Science.gov (United States)

    Lowery, Arthur James; Xie, Yiwei; Zhu, Chen

    2015-08-24

    Orthogonal time division multiplexing (OrthTDM) interleaves sinc-shaped pulses to form a high baud-rate signal, with a rectangular spectrum suitable for multiplexing into a Nyquist WDM (N-WDM)-like signal. The problem with generating sinc-shaped pulses is that they theoretically have infinite durations, and even if time bounded for practical implementation, they still require a filter with a long impulse response, hence a large physical size. Previously a method of creating chirped-orthogonal frequency division multiplexing (OFDM) pulses with a chirped arrayed waveguide (AWG) filter, then converting them into interleaved quasi-sinc pulses using dispersive fiber (DF), has been proposed. This produces a signal with a wider spectrum than the equivalent N-WDM signal. We show that a modification to the scheme enables the spectral extent to be reduced for the same data rate. We then analyse the key factors in designing an OrthTDM transmitter, and relate these to the performance of a N-WDM system. We show that the modified transmitter reduces the required guard band between the N-WDM channels. We also simulate a simpler scheme using an unchirped finite-impulse response filter of similar size, which directly creates truncated-sinc pulses without needing a DF. This gives better system performance than either chirped scheme.

  15. Experimental Investigation of WDM transmission properties for optical labeled signals using orthogonal IM/FSK modulation format

    DEFF Research Database (Denmark)

    Holm-Nielsen, Pablo Villanueva; Zhang, Jianfeng; Olmos, J. J. Vegas

    2004-01-01

    In this paper we report on WDM transmission of optical labeled signals using the orthogonal IM/FSK modulation format aimed for optical packet/burst switching. WDM transmission in both a point-to-point transmission system and a demonstration network with a label-swapping node are implemented....

  16. A New Shared Path Protection Scheme in WDM Optical Networks

    Institute of Scientific and Technical Information of China (English)

    WANGYun; ZENGQingji

    2004-01-01

    Network survivability is a crucial requirement in high-speed optical networks. In this paper, we consider the problem of path protection schemes in WDM(Wavelength division multiplexing) networks with dynamic traffic demands. A new path protection method is proposed, i.e. SRLG-based shared path protection (SRLG-SPP). The SRLG (Shared risk link group) constraint defines the availability of protection resources to a working path, which requires that any two working paths sharing the same risk of failure (or in the same SRLG) cannot share the same protection resources. Furthermore, in our study, we consider a more practical single-link failure model, in which the link-failure-interarrival-time and linkfailure-holding-time are considered as two independent factors. Based on this link-failure model~ extensive numerical simulations are done to compare the resource utilization,protection efficiency and service disruption ratio between SRLG-SPP, Shared path protection (SPP) and Dedicated path protection (DPP) schemes. We show that the developed SRLG-SPP protection scheme performs very well in terms of protection efficiency and service disruption ratio, while it will sacrifice some performances in terms of resource utilization.

  17. Dispersion Compensation Requirements for Optical CDMA Using WDM Lasers

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, A J; Hendandez, V J; Feng, H X C; Heritage, J P; Lennon, W J

    2001-12-10

    Optical code division multiple access (O-CDMA) uses very narrow transmission pulses and is thus susceptible to fiber optic link impairments. When the O-CDMA is implemented as wavelength/time (W/T) matrices which use wavelength division multiplexing (WDM) sources such as multi-frequency laser transmitters, the susceptibility may be higher due to: (a) the large bandwidth utilized and (b) the requirement that the various wavelength components of the codes be synchronized at the point of modulation and encoding as well as after (optical) correlation. A computer simulation based on the nonlinear Schroedinger equation, developed to study optical networking on the National Transparent Optical Network (NTON), was modified to characterize the impairments on the propagation and decoding of W/T matrix codes over a link of the NTON. Three critical link impairments were identified by the simulation: group velocity dispersion (GVD); the flatness of the optical amplifier gain; and the slope of the GVD. Subsequently, experiments were carried out on the NTON link to verify and refine the simulations as well as to suggest improvements in the W/T matrix signal processing design. The NTON link measurements quantified the O-CDMA dispersion compensation requirements. Dispersion compensation management is essential to assure the performance of W/T matrix codes.

  18. Wavelength dimensioning for wavelength-routed WDM satellite network

    Institute of Scientific and Technical Information of China (English)

    Liu Zhe; Guo Wei; Deng Changlin; Hu Weisheng

    2016-01-01

    Internet and broadband applications driven by data traffic demand have become key dri-vers for satellite constellations. The key technology to satisfy the high capacity requirements between satellites is optical satellite networks by means of wavelength division multiplexing inter-satellite links (ISLs) with wavelength routing (WDM-OSN). Due to the limited optical amplifier bandwidth onboard the satellite, it is important to minimize the wavelength requirements to provi-sion requests. However, ISLs should be dynamically established and deleted for each satellite according to its visible satellites. Furthermore, different link assignments will result in different topologies, hence yielding different routings and wavelength assignments. Thus, a perfect match model-based link assignment scheme (LAS-PMM) is proposed to design an appropriate topology such that shorter path could be routed and less wavelengths could be assigned for each ISL along the path. Finally, simulation results show that in comparison to the regular Manhattan street net-work (MSN) topology, wavelength requirements and average end-to-end delay based on the topol-ogy generated by LAS-PMM could be reduced by 24.8%and 12.4%, respectively.

  19. Dynamic multicast routing scheme in WDM optical network

    Science.gov (United States)

    Zhu, Yonghua; Dong, Zhiling; Yao, Hong; Yang, Jianyong; Liu, Yibin

    2007-11-01

    During the information era, the Internet and the service of World Wide Web develop rapidly. Therefore, the wider and wider bandwidth is required with the lower and lower cost. The demand of operation turns out to be diversified. Data, images, videos and other special transmission demands share the challenge and opportunity with the service providers. Simultaneously, the electrical equipment has approached their limit. So the optical communication based on the wavelength division multiplexing (WDM) and the optical cross-connects (OXCs) shows great potentials and brilliant future to build an optical network based on the unique technical advantage and multi-wavelength characteristic. In this paper, we propose a multi-layered graph model with inter-path between layers to solve the problem of multicast routing wavelength assignment (RWA) contemporarily by employing an efficient graph theoretic formulation. And at the same time, an efficient dynamic multicast algorithm named Distributed Message Copying Multicast (DMCM) mechanism is also proposed. The multicast tree with minimum hops can be constructed dynamically according to this proposed scheme.

  20. Multiwavelength arrays of mode-locked lasers for WDM applications

    Science.gov (United States)

    Davis, Lawrence J.; Young, Martin G.; Dougherty, David J.; Keo, Sam A.; Muller, Richard E.; Maker, Paul D.; Forouhar, Siamak

    1998-08-01

    The continued need for increased bandwidth is driving the pursuit of both increased speed in TDM and more channels in WDM for fiber optic communication systems. Multiwavelength arrays of monolithic mode-locked DBR lasers are an attractive source for future high bit rate (100 - 800 Gb/s) optical communication systems. Monolithic mode-locked lasers in the colliding-pulse mode-locked configuration have been fabricated, with DBR end mirrors for wavelength selection. A continuous gain region has been employed for ease of fabrication and the elimination of multiple reflections within the cavity. Arrays containing up to 9 wavelengths have been fabricated, with all the wavelengths within the erbium-doped fiber amplifier gain bandwidth. An RF signal is applied to the saturable absorber for synchronization to an external clock and reduction of the phase noise. For a 4.6 mm cavity, short (< 10 ps) optical pulses at high (approximately 18 GHz) repetition rates have been achieved. Low single side-band phase noise values (-107 dBc/Hz 100 kHz offset) have been demonstrated, nearly equal to that of the RF source.

  1. Warm Dark Matter via Ultra-Violet Freeze-In: Reheating Temperature and Non-Thermal Distribution for Fermionic Higgs Portal Dark Matter

    CERN Document Server

    McDonald, John

    2015-01-01

    Warm dark matter (WDM) of order keV mass may be able to resolve the disagreement between structure formation in cold dark matter simulations and observations. The detailed properties of WDM will depend upon its energy distribution, in particular how it deviates from the thermal distribution usually assumed in WDM simulations. Here we focus on WDM production via the Ultra-Violet (UV) freeze-in mechanism, for the case of fermionic Higgs portal dark matter $\\psi$ produced the portal interaction $\\overline{\\psi}\\psi H^{\\dagger}H/\\Lambda$. We show that the reheating temperature must satisfy $T_{R} \\gtrsim 0.3 $ TeV in order to account for the observed dark matter density when $m_{\\psi} \\approx 2 $ keV, where the lower bound on $T_{R}$ corresponds to the limit where the fermion mass is entirely due to electroweak symmetry breaking via the portal interaction. The corresponding bound on the interaction scale is $\\Lambda \\gtrsim 1.5 \\times 10^{10}$ GeV. We introduce a new method to simplify the computation of the non-...

  2. All-Optical Ultra-High-Speed OFDM to Nyquist-WDM Conversion Based on Complete Optical Fourier Transformation

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Mulvad, Hans Christian Hansen

    2016-01-01

    We propose a novel all-optical ultra-high-speed orthogonal frequency-division multiplexing (OFDM) to Nyquist wavelength-division multiplexing (Nyquist-WDM) conversion scheme, achieved by exchanging the temporal and spectral profiles using a complete optical Fourier transformation (OFT). This scheme...... enables high-speed OFDM to Nyquist-WDM conversion without complex optical/electrical/optical conversion. The all-optical OFDM transmitter is based on the generation of OFDM symbols with a low duty cycle by rectangular temporal gating, which in combination with optical time-division multiplexing yields...... a higher symbol-rate OFDM signal. In the receiver, the converted Nyquist-WDM super-channel is WDM demultiplexed into individual Nyquist-WDM channels using a rectangular optical bandpass filter, followed by optical sampling at the intersymbol-interference free point. In the experimental demonstration...

  3. Probing warm dense lithium by inelastic X-ray scattering

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Saiz, E.; Riley, D. [School of Mathematics and Physics, Queen' s University of Belfast, Belfast (United Kingdom); Gregori, G. [Clarendon Laboratory, University of Oxford, Parks Road, Oxford (United Kingdom); Gregori, G.; Clarke, R.J.; Neely, D.; Notley, M.M.; Spindloe, C. [Central Laser Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX (United Kingdom); Gericke, D.O.; Vorberger, J.; Wunsch, K. [Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry (United Kingdom); Barbrel, B.; Koenig, M. [Laboratoire pour l' Utilisation des Laser Intenses, Ecole Polytechnique - Universite Paris-6, 91 - Palaiseau (France); Freeman, R.R.; Weber, R.L.; Van Woerkom, L. [Department of Physics, The Ohio State University, Columbus, Ohio (United States); Glenzer, S.H.; Landen, O.L.; Neumayer, P.; Price, D. [Lawrence Livermore National Laboratory, Livermore, California (United States); Khattak, F.Y. [Department of Physics, Kohat University of Science and Technology, Kohat-26000, NWFP (Pakistan); Pelka, A.; Roth, M.; Schollmeier, M. [Institut fur Kernphysik, Technische Universitat Darmstadt (Germany)

    2008-10-15

    One of the grand challenges of contemporary physics is understanding strongly interacting quantum systems comprising such diverse examples as ultracold atoms in traps, electrons in high-temperature superconductors and nuclear matter. Warm dense matter, defined by temperatures of a few electron volts and densities comparable with solids, is a complex state of such interacting matter. Moreover, the study of warm dense matter states has practical applications for controlled thermonuclear fusion, where it is encountered during the implosion phase, and it also represents laboratory analogues of astrophysical environments found in the core of planets and the crusts of old stars. Here we demonstrate how warm dense matter states can be diagnosed and structural properties can be obtained by inelastic X-ray scattering measurements on a compressed lithium sample. Combining experiments and ab initio simulations enables us to determine its microscopic state and to evaluate more approximate theoretical models for the ionic structure. (authors)

  4. WDM-PON network simulation with different implementation of optical amplifier in the line

    Science.gov (United States)

    Latal, Jan; Koudelka, Petr; Siska, Petr; Vitasek, Jan; Vasinek, Vladimir

    2014-09-01

    This article is dealing with simulation of deployment of different optical amplifier types in different positions (power amplifier, in-line amplifier, preamplifier) in the WDM-PON network. For simulation available bit rates per chanell were taken in to account, specifically 125 Mbps, 1.25 Gbps and 2.5 Gbps. Optical amplifiers implementation than has influence on possible transmission distance for WDM-PON network. In simulated topology parameters as bit error ratio, attenuation, Q-factor, OSNR, etc. were observed. The whole designed WDM-PON network topology was based on real device Ericsson-LG EAST1100 available on the market. Necessary parameters and data for simulation were obtained from datasheets and real measurements so that the simulation resemble to the real measured results as much as possible.

  5. Design of virtual private networks (VPNs) over optical wavelength-division-multiplexed (WDM) networks

    Science.gov (United States)

    Ramamurthy, Byrav; Ramakrishnan, Ashok

    2000-09-01

    The bandwidth requirements of the Internet are increasing every day and there are newer and more bandwidth-thirsty applications emerging on the horizon. Wavelength division multiplexing (WDM) is the next step towards leveraging the capabilities of the optical fiber, especially for wide-area backbone networks. Virtual private networks are seen as the killer applications of tomorrow, and a great amount of research and development effort is being channeled into finding efficient ways for implementing them. In our work, we introduce the notion of VPNs operating over optical wavelength-routed WDM backbone networks. We formulate the problem of VPN design over optical WDM networks as an integer linear problem. A new method to deal with traffic from diverse VPNs is introduced and its performance analyzed.

  6. Performance analysis of multi-pump Raman+EDFA hybrid amplifiers for WDM systems

    Science.gov (United States)

    Jardim Martini, Márcia M.; Pontes, Maria José; Ribeiro, Moisés. R. N.; Kalinowski, Hypolito José

    2014-08-01

    An approximated technique to optimize the gain profile of multi-pump broadband hybrid amplifiers (Raman+EDFA) under residual pump recycling is applied to a WDM system. The Optimized hybrid amplifier configurations with multi-pumping were analyzed considering different number of input channels in order to check the global gain saturation and the changes in the global gain profile that occur due to signal-pump, signal-signal, and pump-pump interactions. This work extends the optimization of the gain profile from Raman+EDFA hybrid amplifiers and studies the signal-signal interactions, signal-pumping and pumping-pumping WDM systems. Multiple input channels allowed the gain characterization of the Raman+EDFA hybrid amplifier in terms of global gain, ripple, and noise figure considering applications for WDM systems.

  7. A millimeter-wave WDM-ROF system based on supercontinuum technique

    Institute of Scientific and Technical Information of China (English)

    YUAN Quan-xin; YIN Xiao-li; XIN Xiang-jun; YU Chong-xiu; CHEN Yu-lu; MU Bo

    2011-01-01

    In this paper,a new millimeter-wave (mm-wave) wavelength division multiplexing (WDM) system based on radio-overfiber (ROF) technology is proposed.In this approach a multi-wavelength light source is obtained by supercontinuum (SC)technique,and mm-wave signals are obtained by using optical heterodyning method.We experimentally demonstrate the generation of optical carriers for 6-WDM channels,obtain 40 GHz mm-wave signals by employing optical heterodyne technique,and successfully achieve low error rate transmission of 2.5 Gbit/s in WDM channels over a distance of 25 km in a G.652 fiber.The experimental results verify that the proposed solution is feasible and cost effective.

  8. Energy-efficient WDM-OFDM-PON employing shared OFDM modulation modules in optical line terminal.

    Science.gov (United States)

    Hu, Xiaofeng; Zhang, Liang; Cao, Pan; Wang, Kongtao; Su, Yikai

    2012-03-26

    We propose and experimentally demonstrate a scheme to improve the energy efficiency of wavelength division multiplexing - orthogonal frequency division multiplexing - passive optical networks (WDM-OFDM-PONs). By using an N × M opto-mechanic switch in optical line terminal (OLT), an OFDM modulation module is shared by several channels to deliver data to multiple users with low traffic demands during non-peak hours of the day, thus greatly reducing the number of operating devices and minimizing the energy consumption of the OLT. An experiment utilizing one OFDM modulation module to serve three optical network units (ONUs) in a WDM-OFDM-PON is performed to verify the feasibility of our proposal. Theoretical analysis and numerical calculation show that the proposed scheme can achieve a saving of 23.6% in the energy consumption of the OFDM modulation modules compared to conventional WDM-OFDM-PON.

  9. Collision-induced timing jitter in dispersion-managed WDM soliton system with filtering

    Institute of Scientific and Technical Information of China (English)

    Jianxin Du(杜建新); Qihong Lou(楼祺洪)

    2004-01-01

    Taking into account the randomicity of collision positions and the arbitrary encoding of data in channel,the influences of different dispersion management on collision-induced timing jitter in a filtered wavelength division multiplexing (WDM) soliton system are obtained statistically and numerically by applying a set of coupled ordinary differential equations which are derived through variational procedure. The optimal dispersion managements which can greatly reduce the collision-induced timing jitter are found. The multi-channel collision-induced timing jitters in a filtered WDM soliton system are given with an optimal dispersion management and constant dispersion.

  10. 16×10Gb/s symmetric WDM-FOFDM-PON realization with colorless ONUs.

    Science.gov (United States)

    Lei, Cheng; Chen, Hongwei; Chen, Minghua; Xie, Shizhong

    2011-08-01

    A novel symmetric WDM-PON scheme with colorless ONU is proposed. The baseband 4-ASK Fast-OFDM signal is upconverted by an intermediate frequency carrier, reserving a frequency gap between the FOFDM signal and the optical carrier. After distributing different wavelengths to corresponding ONU by AWG, periodic BPFs are employed to extract the optical carriers for upstream transmission, achieving colorless ONUs. A WDM-PON system with 16 colorless ONUs is established, and 10-Gb/s symmetric transmission for each ONU is also realized. Experiment shows that the system tolerance to the intrachannel crosstalk is greatly improved when the crosstalk signal locates at relatively higher frequency band.

  11. Novel algorithm of finding good candidate pre-configuration cycles in survivable WDM mesh network

    Institute of Scientific and Technical Information of China (English)

    ZHAO Tai-fei; YU Hong-fang; LI Le-min

    2006-01-01

    We present a novel algorithm of finding cycles, called the Fast Cycles Mining Algorithm (FCMA),for effi cient p-cycle network design in WDM networks. The algorithm is also flexible in that the number and the length of cycles generated are controlled by several input parameters. The problem of wavelength assign ment on p-cycle is considered in the algorithm. This algorithm is scalable and especially suitable for surviv able WDM mesh networks. Finally, the performance of the algorithm is gauged by running on some real world network topologies.

  12. 16 channel WDM regeneration in a single phase-sensitive amplifier through optical Fourier transformation

    DEFF Research Database (Denmark)

    Guan, Pengyu; Da Ros, Francesco; Lillieholm, Mads

    2016-01-01

    We demonstrate simultaneous phase regeneration of 16-WDM DPSK channels using optical Fourier transformation and a single phase-sensitive amplifier. The BERs of 16-WDM×10-Gbit/s phase noise degraded DPSK signals are improved by 0.4-1.3 orders of magnitude......We demonstrate simultaneous phase regeneration of 16-WDM DPSK channels using optical Fourier transformation and a single phase-sensitive amplifier. The BERs of 16-WDM×10-Gbit/s phase noise degraded DPSK signals are improved by 0.4-1.3 orders of magnitude...

  13. Impairment analysis of WDM-PON based on low-cost tunable lasers

    DEFF Research Database (Denmark)

    Wagner, Christoph; Eiselt, Michael H.; Lawin, Mirko

    2016-01-01

    channel must be kept below 15%. Similar values result for the upstream pilot tones. In order to limit crosstalk, such systems require reduced launch power during wavelength tuning and can cover up to 40 km differential reach. These results confirm that WDM-PON based on low-cost lasers is a technically......WDM-PON is considered for next-generation broadband backhaul and radio access networking. Among different implementation choices, we propose to utilize low-cost tunable lasers at the remote sites, together with a centralized wavelength locker. Practical implementations require a transparently added...

  14. Wavelength initialization employing wavelength recognition scheme in WDM-PON based on tunable lasers

    Science.gov (United States)

    Mun, Sil-Gu; Lee, Eun-Gu; Lee, Jong Hyun; Lee, Sang Soo; Lee, Jyung Chan

    2015-01-01

    We proposed a simple method to initialize the wavelength of tunable lasers in WDM-PON employing wavelength recognition scheme with an optical filter as a function of wavelength and accomplished plug and play operation. We also implemented a transceiver based on our proposed wavelength initialization scheme and then experimentally demonstrated the feasibility in WDM-PON configuration guaranteeing 16 channels with 100 GHz channel spacing. Our proposal is a cost-effective and easy-to-install method to realize the wavelength initialization of ONU. In addition, this method will support compatibility with all kind of tunable laser regardless of their structures and operating principles.

  15. Warm Dark Matter from keVins

    Energy Technology Data Exchange (ETDEWEB)

    King, Stephen F.; Merle, Alexander, E-mail: S.F.King@soton.ac.uk, E-mail: A.Merle@soton.ac.uk [School of Physics and Astronomy, University of Southampton, Highfield, Southampton, SO17 1BJ (United Kingdom)

    2012-08-01

    We propose a simple model for Warm Dark Matter (WDM) in which two fermions are added to the Standard Model: (quasi-) stable ''keVins'' (keV inert fermions) which account for WDM and their unstable brothers, the ''GeVins'' (GeV inert fermions), both of which carry zero electric charge and zero lepton number, and are (approximately) ''inert'', in the sense that their only interactions are via suppressed couplings to the Z. We consider scenarios in which stable keVins are thermally produced and their abundance is subsequently diluted by entropy production from the decays of the heavier unstable GeVins. This mechanism could be implemented in a wide variety of models, including E{sub 6} inspired supersymmetric models or models involving sterile neutrinos.

  16. Lyman-alpha constraints on warm and on warm-plus-cold dark matter models

    CERN Document Server

    Boyarsky, Alexey; Ruchayskiy, Oleg; Viel, Matteo

    2009-01-01

    We revisit Lyman-alpha bounds on the dark matter mass in Lambda Warm Dark Matter (Lambda-WDM) models, and derive new bounds in the case of mixed Cold plus Warm models (Lambda-CWDM), using a set up which is a good approximation for several theoretically well-motivated dark matter models. We combine WMAP5 results with two different Lyman-alpha data sets, including observations from the Sloan Digital Sky Survey. We pay a special attention to systematics, test various possible sources of error, and compare the results of different statistical approaches. Expressed in terms of the mass of a non-resonantly produced sterile neutrino, our bounds read m_NRP > 8 keV (frequentist 99.7% confidence limit) or m_NRP > 12.1 keV (Bayesian 95% credible interval) in the pure Lambda-WDM limit. For the mixed model, we obtain limits on the mass as a function of the warm dark matter fraction F_WDM. Within the mass range studied here (5 keV < m_NRP < infinity), we find that any mass value is allowed when F_WDM < 0.6 (freque...

  17. Research on 100G WDM/OTN Technology and Its Application to Engineering%100G WDM/OTN技术及工程设计研究

    Institute of Scientific and Technical Information of China (English)

    赵小强; 王迎春; 李勇

    2013-01-01

    Based on the actual requirement of operators, it analyzes 100G WDM/OTN technology and equipment condition from the as-pects of long distance transmission technology, multi-service supporting capability, electrical cross-connection based on ODUk, reliability and online performance monitoring. Finaly it discusses the engineering designing.%  针对运营商的实际需求,从长距离传输技术、多业务支持能力、基于ODUk的电交叉能力、可靠性、在线性能监测等方面分析了100G WDM/OTN技术和设备现状,最后对工程设计进行了探讨。

  18. Modelling dense relational data

    DEFF Research Database (Denmark)

    Herlau, Tue; Mørup, Morten; Schmidt, Mikkel Nørgaard;

    2012-01-01

    Relational modelling classically consider sparse and discrete data. Measures of influence computed pairwise between temporal sources naturally give rise to dense continuous-valued matrices, for instance p-values from Granger causality. Due to asymmetry or lack of positive definiteness they are no......Relational modelling classically consider sparse and discrete data. Measures of influence computed pairwise between temporal sources naturally give rise to dense continuous-valued matrices, for instance p-values from Granger causality. Due to asymmetry or lack of positive definiteness...... they are not naturally suited for kernel K-means. We propose a generative Bayesian model for dense matrices which generalize kernel K-means to consider off-diagonal interactions in matrices of interactions, and demonstrate its ability to detect structure on both artificial data and two real data sets....

  19. Experimental validation of concept for real-time wavelength monitoring and tracking in densely populated WDM networks

    Science.gov (United States)

    Vukovic, Alex; Savoie, Michel; Hua, Heng; Campbell, Scott; Nguyen, Thao

    2005-10-01

    As the telecom industry responds with technological innovations to requests for higher data rates, increased number of wavelengths at higher densities, longer transmission distances and more intelligence for next generation optical networks, new monitoring schemes based on monitoring and tracking of each wavelength need to be developed and deployed. An optical layer monitoring scheme, based on tracking key optical parameters per each wavelength, is considered to be one of enablers for the transformation of today's opaque networks to dynamic, agile future networks. Ever-tighter network monitoring and control will be required to fulfill customer Service Level Agreements (SLAs). A wavelength monitoring and tracking concept was developed as a three-step approach. It started with the identification of all critical parameters required to obtain sufficient information about each wavelength; followed by the deployment of a cost-efficient device to provide simultaneous, accurate measurements in real-time of all critical parameters; and finally, the formulation of a specification for wavelength monitoring and tracking devices for real-time, simultaneous measurements and processing the data. A prototype solution based on a commercially available integrated modular spectrometer within a testbed environment associated with the all-optical network (AON) demonstrator program was used to verify and validate the wavelength monitoring and tracking concept. The developed concept verified that it can manage tracking of 32 wavelengths within a wavelength division multiplexing network. The developed concept presented in this paper can be used inside the transparent domains of networks to detect, identify and locate signal degradations in real-time, even sometimes to recognize the cause of the failure. Aside from the reduction of operational expenses due to the elimination of the need for operators at every site and skilled field technicians to isolate and repair faults, the developed wavelength monitoring concept provides critical inputs for protection switching, line equalization and span monitoring. Additionally, it can unlock the capabilities of tunable technologies, ensuring network agility. Finally, further developments of the presented concept might enable building and controlling of complex network topologies while efficiently maintaining a high quality of service (QoS).

  20. Constraining warm dark matter mass with cosmic reionization and gravitational wave

    CERN Document Server

    Tan, W W; Cheng, K S

    2016-01-01

    We constrain the warm dark matter (WDM) particle mass with the observations of cosmic reionization and CMB optical depth. We suggest that the GWs from stellar mass black holes (BHs) could give a further constraint on WDM particle mass for future observations. The star formation rates (SFRs) of Population I/II (Pop I/II) and Population III (Pop III) stars are also derived. If the metallicity of the universe have been enriched beyond the critical value of $Z_{\\rm crit}=10^{-3.5}Z_{\\odot}$, the star formation shift from Pop III to Pop I/II stars. Our results show that the SFRs are quite dependent on the WDM particle mass, especially at high redshifts. Combing with the reionization history and CMB optical depth derived from the recent \\emph{Planck} mission, we find that the current data requires the WDM particle mass in a narrow range of $1 < m_x < 3$ keV. Furthermore, we suggest that the stochastic gravitational wave background (SGWB) produced by stellar BHs could give a further constraint on the WDM parti...

  1. Optimization of Generation and Detection of WDM Signals with Advanced Modulation Formats

    Institute of Scientific and Technical Information of China (English)

    Sarah; Dods

    2003-01-01

    This paper presents optimal generation and detection of wavelength division multiplexed (WDM) signals with advanced modulation formats. We investigate the relative phase alignment between phase modulation and data bits for chirped return-to-zero (CRZ) signals, and the frequency offset between the RZ carrier and various optical filters for vestigial side band (VSB)-RZ signals.

  2. A Novel Line Coding Pair for Fully Passive Long Reach {WDM-PON}s

    DEFF Research Database (Denmark)

    Presi, Marco; Proietti, Roberto; Prince, Kamau;

    2008-01-01

    A novel line coding pair allows to use unsaturated flective-SOAs as upstream remodulator in long-reach WDM-PONs. Full-duplex and symmetric 80 km reach is demonstrated without in-line amplification at 1.25 Gb/s...

  3. Fiber nonlinearity compensation of an 8-channel WDM PDM-QPSK signal using multiple phase conjugations

    DEFF Research Database (Denmark)

    Hu, Hao; Jopson, R. M.; Dinu, M.;

    2013-01-01

    We demonstrate compensation of fiber nonlinearities using optical phase conjugation of an 8-chamiel WDM 32-Gbaud PDM QPSK signal. Conjugating phase every 600 km in a fiber loop enabled a 6000 km transmission over True Wave fiber. © 2013 Optical Society of America....

  4. Demonstration of digital fronthaul over self-seeded WDM-PON in commercial LTE environment.

    Science.gov (United States)

    Ma, Yiran; Xu, Zhiguang; Zhang, Chengliang; Lin, Huafeng; Wang, Qing; Zhou, Min; Wang, Heng; Yu, Jingwen; Wang, Xiaomu

    2015-05-01

    CPRI between BBU and RRU equipment is carried by self-seeded WDM-PON prototype system within commercial LTE end-to-end environment. Delay and jitter meets CPRI requirements while services demonstrated show the same performance as bare fiber.

  5. Tailored design of WDM filters in BCB embedded PhC membranes

    DEFF Research Database (Denmark)

    Malaguti, Stefania; Bellanca, Gaetano; Ottaviano, Luisa

    2013-01-01

    We propose a design strategy for wavelength division multiplexing (WDM) filters in BCB embedded photonic crystal membranes. Due to the weaker vertical confinement determined by the material embedding the whole structure, accurate tailoring of the resonant cavity and of both bus and drop waveguide...

  6. Simultaneous regeneration of two 160 Gbit/s WDM channels in a single highly nonlinear fiber

    DEFF Research Database (Denmark)

    Wang, Ju; Ji, Hua; Hu, Hao;

    2013-01-01

    We experimentally demonstrate simultaneous all-optical regeneration of two 160-Gbit/s wavelength-division multiplexed (WDM) channels in a single highly nonlinear fiber (HNLF). The multi-channel regeneration performance is confirmed by bit-error rate (BER) measurements. The receiver powers at a BE...

  7. Simultaneous Regeneration of Two 160 Gbit/s WDM Channels in a Single Highly Nonlinear Fiber

    DEFF Research Database (Denmark)

    Wang, Ju; Ji, Hua; Hu, Hao;

    2012-01-01

    We experimentally demonstrate simultaneous all-optical regeneration of two 160 Gbit/s WDM channels in a single HNLF using fiber optical parametric amplification. Receiver sensitivities at a BER of 10-9 are improved by about 2.1 dB and 4.9 dB for the two channels, respectively. The BER is not degr...

  8. Integration of Optically Generated Impulse Radio UWB Signals into Baseband WDM-PON

    DEFF Research Database (Denmark)

    Pham, Tien Thang; Yu, Xianbin; Dittmann, Lars

    2011-01-01

    We propose a compact integration system to simultaneously provide wireline and wireless (baseband and ultra-wide band (UWB)) services to end-users in a WDM-PON. A 1-Gbps UWB signal is optically generated and shares the same wavelength with the baseband signal. Error-free performance was achieved ...

  9. Combined Optical and Electrical Spectrum Shaping for High-Baud-Rate Nyquist-WDM Transceivers

    DEFF Research Database (Denmark)

    Porto da Silva, Edson; Borkowski, Robert; Preussler, Stefan;

    2016-01-01

    We discuss the benefits and limitations of optical time-division multiplexing 22 (OTDM) techniques based on the optical generation of a periodic train of sinc pulses for 23 wavelength-division multiplexing (WDM) transmission at high baud rates. It is shown 24 how the modulated OTDM spectrum bandw...

  10. Constellation Shaping for WDM systems using 256QAM/1024QAM with Probabilistic Optimization

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Da Ros, Francesco; Porto da Silva, Edson

    2016-01-01

    /symbol. It is shown that rate adaptation does not require changing ofthe modulation format. The performance of the proposed 1024QAM shaped system isvalidated on all 5 channels of the WDM signal for selected distances and rates.Finally, it was shown via EXIT charts and BER analysis that iterativedemapping, while...

  11. Field Trial of 40 Gb/s Optical Transport Network using Open WDM Interfaces

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Ruepp, Sarah Renée; Petersen, Martin Nordal;

    2013-01-01

    An experimental field-trail deployment of a 40Gb/s open WDM interface in an operational network is presented, in cross-carrier interconnection scenario. Practical challenges of integration and performance measures for both native and alien channels are outlined....

  12. Characteristics of WDM Couplers Based on 80 μm Cladding Fiber

    Institute of Scientific and Technical Information of China (English)

    Hyunsook; Shin; Woojin; Shin; Manjung; Han; Kyoungrok; Kim; Seungryong; Han; Yunsong; Jeong; K.; Oh

    2003-01-01

    We have fabricated 1310/1550 and 1480/1550nm WDM couplers using a fiber of 80μm cladding diameter, whose tapering length is shortened by 4~8mm for the identical coupling strength compared to those of 125μm cladding fibers. We also report their splicing loss to conventional single mode fibers.

  13. A Heuristic Algorithm for P-Cycles Configuration in WDM Optical Networks

    Institute of Scientific and Technical Information of China (English)

    Zhenrong Zhang; Wen-De Zhong; Biswanath Mukherjee

    2003-01-01

    Aiming at minimizing spare capacity for optical WDM networks, we propose a new heuristic algorithm for preconfigured protection cycle (p-cycle) design. Numerical results show that the spare capacity obtained by our new algorithm is very close to the optimal solution.

  14. Nyquist-WDM filter shaping with a high-resolution colorless photonic spectral processor.

    Science.gov (United States)

    Sinefeld, David; Ben-Ezra, Shalva; Marom, Dan M

    2013-09-01

    We employ a spatial-light-modulator-based colorless photonic spectral processor with a spectral addressability of 100 MHz along 100 GHz bandwidth, for multichannel, high-resolution reshaping of Gaussian channel response to square-like shape, compatible with Nyquist WDM requirements.

  15. Investigation of Cross-Phase Modulation in WDM Systems with NRZ and RZ Modulation Formats

    DEFF Research Database (Denmark)

    Yu, Jianjun; Jeppesen, Palle

    2000-01-01

    Our experimental and numerical results show that there is no large difference of XPM-induced intensity interferences between NRZ and RZ format with a duty cycle larger than a certain value in WDM systems of multi-span SMF or TW fibers....

  16. 16 channel WDM regeneration in a single phase-sensitive amplifier through optical Fourier transformation

    DEFF Research Database (Denmark)

    Guan, Pengyu; Da Ros, Francesco; Lillieholm, Mads

    2016-01-01

    We demonstrate simultaneous phase regeneration of 16-WDM DPSK channels using optical Fourier transformation and a single phase-sensitive amplifier. The BERs of 16-WDM×10-Gbit/s phase noise degraded DPSK signals are improved by 0.4-1.3 orders of magnitude...

  17. Dynamic traffic grooming in distributed-controlled IP/WDM optical mesh networks

    Institute of Scientific and Technical Information of China (English)

    Huang Jun; Zeng Qingji; Liu Jimin; Xiao Pengcheng; Liu Hua; Xiao Shilin

    2005-01-01

    In this paper, the study was devoted to the traffic-grooming problem in a distributed-controlled WDM mesh network. We studied the optimization of the maximal number of ports configured at each node in the network. We gave the maximumnumber simulation results in different network environment, which could be taken as a reference for network design.

  18. Experimental Study of Nonlinear Phase Noise and its Impact on WDM Systems with DP-256QAM

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Da Ros, Francesco; Porto da Silva, Edson

    2016-01-01

    A probabilistic method for mitigating the phase noise component of the non-linear interference in WDM systems with Raman amplification is experimentally demonstrated. The achieved gains increase with distance and are comparable to the gains of single-channel digital back-propagation....

  19. Low-Complexity Tracking of Laser and Nonlinear Phase Noise in WDM Optical Fiber Systems

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Fehenberger, Tobias; Barletta, Luca;

    2015-01-01

    In this paper, the wavelength division multiplexed (WDM) fiber optic channel is considered. It is shown that for ideal distributed Raman amplification (IDRA), the Wiener process model is suitable for the non-linear phase noise due to cross phase modulation from neighboring channels. Based...

  20. A 80 km reach fully passive WDM-PON based on reflective ONUs

    DEFF Research Database (Denmark)

    Presi, Marco; Proietti, Roberto; Prince, Kamau

    2008-01-01

    We propose a novel line coding combination (Inverse RZ coding in downlink and RZ in uplink) that extends the reach of WDM Passive Optical Networks based on Reflective SOAs with no in-line amplification. We achieved full downstream remodulation even when feeding the reflective SOA with power level...

  1. The RoF-WDM-PON for Wireless and Wire Layout with Multi-wavelength Fiber Laser and Carrier Reusing

    Science.gov (United States)

    Ji, Wei; Zheng, Zhuowen

    2013-09-01

    In this paper, we design a WDM-RoF-PON based on multi-wavelength fiber laser and CSRZ-DPSK, which can achieve wire-line and wireless access synchronously without any RF source in ONU. The multi-wavelength fiber laser is the union light source of WDM-PON. By the RSOA and downstream light source reusing, the ONU can also omit laser source and makes the WDM-PON to be colorless. The networking has the credible transmission property, including wireless access and fiber transmission. The networking also has excellent covering range.

  2. Merger histories in warm dark matter structure formation scenarios

    Science.gov (United States)

    Knebe, Alexander; Devriendt, Julien E. G.; Mahmood, Asim; Silk, Joseph

    2002-02-01

    Observations on galactic scales seem to be in contradiction with recent high-resolution N-body simulations. This so-called cold dark matter (CDM) crisis has been addressed in several ways, ranging from a change in fundamental physics by introducing self-interacting cold dark matter particles to a tuning of complex astrophysical processes such as global and/or local feedback. All these efforts attempt to soften density profiles and reduce the abundance of satellites in simulated galaxy haloes. In this paper, we explore a different approach that consists of filtering the dark matter power spectrum on small scales, thereby altering the formation history of low-mass objects. The physical motivation for damping these fluctuations lies in the possibility that the dark matter particles have a different nature, i.e. are warm (WDM) rather than cold. We show that this leads to some interesting new results in terms of the merger history and large-scale distribution of low-mass haloes, compared with the standard CDM scenario. However, WDM does not appear to be the ultimate solution, in the sense that it is not able to fully solve the CDM crisis, even though one of the main drawbacks, namely the abundance of satellites, can be remedied. Indeed, the cuspiness of the halo profiles still persists, at all redshifts, and for all haloes and sub-haloes that we investigated. Despite the persistence of the cuspiness problem of DM haloes, WDM seems to be still worth taking seriously, as it alleviates the problems of over-abundant sub-structures in galactic haloes and possibly the lack of angular momentum of simulated disc galaxies. WDM also lessens the need to invoke strong feedback to solve these problems, and may provide a natural explanation of the clustering properties and ages of dwarfs.

  3. WDM网络中任播请求的平衡分析%Equilibrium Analysis for Anycast in WDM Networks

    Institute of Scientific and Technical Information of China (English)

    TANG Mao-ning; WANG Han-xing

    2005-01-01

    In this paper, the wavelength-routed WDM network was analyzed for the dynamic case where the arrival of anycast requests was modeled by a state-dependent Poisson process. The equilibrium analysis was also given with the UWNC algorithm.

  4. Transmission and pass-drop operations of mixed baudrate Nyquist OTDM-WDM signals for all-optical elastic network.

    Science.gov (United States)

    Tan, Hung Nguyen; Inoue, Takashi; Kurosu, Takayuki; Namiki, Shu

    2013-08-26

    We propose the use of Nyquist OTDM-WDM signal for highly efficient, fully elastic all-optical networks. With the possibility of generation of ultra-coarse yet flexible granular channels, Nyquist OTDM-WDM can eliminate guard-bands in conventional WDM systems, and hence improves the spectral efficiency in network perspective. In this paper, transmission and pass-drop operations of mixed baudrate Nyquist OTDM-WDM channels from 43 Gbaud to dual-polarization 344 Gbaud are successfully demonstrated over 320 km fiber link with four FlexGrid-compatible WSS nodes. A stable clock recovery is also carried out for different baudrate Nyquist OTDMs by optical null-header insertion technique.

  5. Dense Plasma Focus Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Li, Shengtai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jungman, Gerard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hayes-Sterbenz, Anna Catherine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-31

    The mechanisms for pinch formation in Dense Plasma Focus (DPF) devices, with the generation of high-energy ions beams and subsequent neutron production over a relatively short distance, are not fully understood. Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics and its associated instabilities and neutron production.

  6. Time lens based optical fourier transformation for advanced processing of spectrally-efficient OFDM and N-WDM signals

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Morioka, Toshio

    2016-01-01

    We review recent progress in the use of time lens based optical Fourier transformation for advanced optical signal processing, with focus on all-optical generation, detection and format conversion of spectrally-efficient OFDM and N-WDM signals.......We review recent progress in the use of time lens based optical Fourier transformation for advanced optical signal processing, with focus on all-optical generation, detection and format conversion of spectrally-efficient OFDM and N-WDM signals....

  7. Reionizing the Universe in Warm Dark Matter cosmologies

    CERN Document Server

    Dayal, Pratika; Bromm, Volker; Pacucci, Fabio

    2015-01-01

    We compare model results from our semi-analytic merger tree based framework for high-redshift ($z \\simeq 5-20$) galaxy formation against reionization indicators including the Planck electron scattering optical depth ($\\tau_{es}$) and the ionizing photon emissivity ($\\dot n_{ion}$) to constrain the particle mass of Warm Dark Matter (WDM). Our framework traces the Dark Matter (DM) and baryonic assembly of galaxies in 4 DM cosmologies: Cold Dark Matter (CDM) and WDM with a particle mass of $m_x = 2.25,3$ and 5 keV. It includes all the key processes of star formation, supernova feedback, the merger/accretion/ejection driven evolution of gas and stellar mass, and the effect of the ultra-violet background (UVB) created during reionization in photo-evaporating the gas content of galaxies in halos with $M_h \\leq 10^9 M_\\odot$. We show that current Planck $\\tau_{es}$ values rule out $m_x \\leq 2.5$ keV WDM, even in the physically unlikely scenario that all ionizing photons produced by these galaxies escape and contribu...

  8. Coalescence preference in dense packing of bubbles

    Science.gov (United States)

    Kim, Yeseul; Gim, Bopil; Gim, Bopil; Weon, Byung Mook

    2015-11-01

    Coalescence preference is the tendency that a merged bubble from the contact of two original bubbles (parent) tends to be near to the bigger parent. Here, we show that the coalescence preference can be blocked by densely packing of neighbor bubbles. We use high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence phenomenon which occurs in micro scale seconds and inside dense packing of microbubbles with a local packing fraction of ~40%. Previous theory and experimental evidence predict a power of -5 between the relative coalescence position and the parent size. However, our new observation for coalescence preference in densely packed microbubbles shows a different power of -2. We believe that this result may be important to understand coalescence dynamics in dense packing of soft matter. This work (NRF-2013R1A22A04008115) was supported by Mid-career Researcher Program through NRF grant funded by the MEST and also was supported by Ministry of Science, ICT and Future Planning (2009-0082580) and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry and Education, Science and Technology (NRF-2012R1A6A3A04039257).

  9. A WDM model for the evolution of galactic halos

    CERN Document Server

    Acedo, L

    2011-01-01

    It is a well-known fact that the gravitational effect of dark matter in galaxies is only noticeable when the orbital accelerations drop below $a_0 \\simeq 2\\times 10^{-8}$ cm s$^{-1}$ (Milgrom's Law). This peculiarity of the dynamic behaviour of galaxies was initially ascribed to a modification of Newtonian dynamics (MOND theory) and, consequently, it was used as an argument to criticize the dark matter hypothesis. In our model, warm dark matter is composed by collisionless Vlasov particles with a primordial typical velocity $\\simeq 330$ km s$^{-1}$ and, consequently, they evaporated from galactic cores and reorganized in halos with a cusp at a finite distance from the galactic center (in contrast with Cold Dark Matter simulations which predict a cusp at the center of galaxies). This is confirmed by mean-field N-body simulations of the self-gravitating Vlasov dark matter particles in the potential well of the baryonic core. The rest mass of these particles, $\\mu$, is determined from a kinetic theory of the ear...

  10. Compact 4-channel AWGs for CWDM and LAN WDM in data center monolithic applications

    Science.gov (United States)

    Pan, Pan; An, Junming; Wang, Yue; Zhang, Jiashun; Wang, Liangliang; Qi, Ying; Han, Qin; Hu, Xiongwei

    2015-12-01

    InP-based 4-channel AWGs for Coarse Wavelength Division Multiplexing (CWDM) with channel spacing of 20 nm and Local Area Network (LAN) WDM with channel spacing of 800 GHz are designed and fabricated. The deep-ridge waveguide is used to make the chip compact, chip size of AWG for CWDM is 0.55×3.9 mm2 and for LAN WDM is 1.6×3 mm2. The measured results indicate that, the insertion losses are -5 dB and -7 dB, crosstalk levels are below -25 dB and -24 dB for AWG with 20 nm channel spacing and 800 GHz channel spacing, respectively. These AWGs can be integrated with lasers and detectors array monolithically for data center applications.

  11. Threshold based Bit Error Rate Optimization in Four Wave Mixing Optical WDM Systems

    Directory of Open Access Journals (Sweden)

    Er. Karamjeet Kaur

    2016-07-01

    Full Text Available Optical communication is communication at a distance using light to carry information which can be performed visually or by using electronic devices. The trend toward higher bit rates in light-wave communication has interest in dispersion-shifted fibre to reduce dispersion penalties. At an equivalent time optical amplifiers have exaggerated interest in wavelength multiplexing. This paper describes optical communication systems where we discuss different optical multiplexing schemes. The effect of channel power depletion due to generation of Four Wave Mixing waves and the effect of FWM cross talk on the performance of a WDM receiver has been studied in this paper. The main focus is to minimize Bit Error Rate to increase the QoS of the optical WDM system.

  12. Advanced Broadcast/Multicast Channel Capable Carrier Reuse WDM-PON

    Directory of Open Access Journals (Sweden)

    Ashish Nema

    2013-02-01

    Full Text Available Advanced broadcast/multicast carriers reuse WDM-PON is mainly used to provide the broadcast and unicast signal at the destination end. It uses the splitting capability of a power splitter and the cyclic property of arrayed waveguide grating at the middle remote node. The broadcast channel with the help of AWG and with a dedicated unicast channel can be overlaid and subsequently transmitted to each Optical network unit (ONU simultaneously. Another advantage of this WDM-PON a very small interface between the broadcast channel and with the unicast channel and it is shared by all ONU. The optical carrier to subcarrier ratio on the bit error rate performance can be minimized by increasing the extinction ratio of the delay interferometer used at remote node. The result is implemented by opti-system 7.0 software tools

  13. SCM/WDM-PON with in-service baseband embedded OTDR monitoring

    Science.gov (United States)

    Villafani Caballero, D.; Almeida, R. P.; Urban, P. J.; Costa, J. C. W. A.; von der Weid, J. P.; Chen, J.

    2015-12-01

    Subcarrier Multiplexing and Wavelength Division Multiplexing Passive Optical Network (SCM/WDM-PON) is a promising solution to support Radio over Fiber (RoF) for the convergence of optical and wireless access networks. In this paper, we propose a novel SCM/WDM-PON system with in-service baseband monitoring, which uses an optical carrier to supervise the fiber infrastructure and several subcarriers to transmit data signals simultaneously. The performance of the proposed system is investigated where an embedded baseband Optical Time Domain Reflectometry (OTDR) signal is applied for fiber fault monitoring. The results have verified the feasibility of the proposed system and shown that with proper configuration the in-service baseband monitoring signals have negligible impact on data transmission.

  14. A Distributed Routing and Wavelength Assignment Algorithm for Online Muiticast in All-Optical WDM Networks

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Routing and wavelength assignment for online real-time multicast connection setup is a difficulttask due to the dynamic change of availabilities of wavelengths on links and the consideration of wave-length conversion delay in WDM networks. This paper presents a distributed routing and wavelength as-signment scheme for the setup of real-time multicast connections. It integrates routing and wavelength as-signment as a single process, which greatly reduces the connection setup time. The proposed routingmethod is based on the Prim's MST (Minimum Spanning Tree) algorithm and the K-restricted breadth-first search method, which can produce a sub-minimal cost tree under a given delay bound. The wave-length assignment uses the least-conversion and load balancing strategies. Simulation results show that theproposed algorithm is suitable for online multicast connection establishment in WDM networks.

  15. Optimizing Fiber Topologies for WDM Optical Networks Based on Multi-Granularity Optical Switching Technology

    Institute of Scientific and Technical Information of China (English)

    LI Junjie; ZHOU Bingkun; ZHANG Hanyi; LI Yanhe

    2006-01-01

    For the quality of service (QoS) and fairness considerations, the hop counts of various lightpaths in a wavelength division multiplexing (WDM) optical network should be short and compact. The development of multi-granularity optical switching technology has made it possible to construct various fiber topologies over a fixed physical topology. This paper describes a fiber topology design (FTD) problem, which minimizes the maximum number of required fibers in the physical links for a maximum lightpath hop count in the fiber topology. After the formular description for the FTD problem, a method was given to obtain the lower bound on the maximum number of required fibers. For large or moderate scale networks, three heuristic algorithms are given to efficiently solve the FTD problem. This study gives a new way to optimize the resource configuration performance in WDM optical networks at the topology level and proves its effectiveness via both analyses and numerical experiments.

  16. Experimental demonstration of security-enhanced WDM-PON based on chaotic optical communications

    Science.gov (United States)

    Yin, Hongxi; Chen, Xiaolei; Yue, Hehe; Zhao, Qingchun; Hao, Yang; Wu, Chenguang; Zhao, Nan

    2015-08-01

    The message-decryption process of subtracting chaotic synchronization carrier from receiving signal is explained by modeling and numerically solving the rate equations for semiconductor lasers. An experimental system of wavelength division multiplexing passive optical network (WDM-PON) based on chaotic-light secure communications is first built up. The bidirectional transmissions of downstream and upstream data are experimentally realized with only two lasers and a single wavelength channel in a WDM fiber-optic link. When the data rate is 1.25 Gb/s, the secure transmission distance can be up to 11 km with SSMF of G.652. After sampling and decision, the BER of the recovered messages is calculated to be approximately 1×10-4.

  17. Transfer matrix analysis of backscattering and reflection effects on WDM-PON systems.

    Science.gov (United States)

    Simatupang, Joni Welman; Lee, San-Liang

    2013-11-18

    This paper proposes using power transfer matrix analysis to characterize the effects of Rayleigh backscattering and Fresnel reflection on WDM-PON systems. The modeling of a WDM-PON system can be carried out simply by matrix multiplication of the corresponding matrices for all the building blocks, where all possible guided backward lights and resonant configurations along the optical network can be accounted for. The total sum of all interferences affecting the bidirectional transmission that leads to an optical crosstalk-to-signal (C/S) ratio can be modeled as back-reflections through cascaded two-port networks for the downstream and upstream signals. This approach is simple, robust, efficient, and also accurate. Its accuracy is verified for simple system architectures and then applied to study more complicated cases. The results show its versatility to analyze a wide variety of bidirectional optical transmission systems.

  18. Valiant load-balanced robust routing under hose model for WDM mesh networks

    Science.gov (United States)

    Zhang, Xiaoning; Li, Lemin; Wang, Sheng

    2006-09-01

    In this paper, we propose Valiant Load-Balanced robust routing scheme for WDM mesh networks under the model of polyhedral uncertainty (i.e., hose model), and the proposed routing scheme is implemented with traffic grooming approach. Our Objective is to maximize the hose model throughput. A mathematic formulation of Valiant Load-Balanced robust routing is presented and three fast heuristic algorithms are also proposed. When implementing Valiant Load-Balanced robust routing scheme to WDM mesh networks, a novel traffic-grooming algorithm called MHF (minimizing hop first) is proposed. We compare the three heuristic algorithms with the VPN tree under the hose model. Finally we demonstrate in the simulation results that MHF with Valiant Load-Balanced robust routing scheme outperforms the traditional traffic-grooming algorithm in terms of the throughput for the uniform/non-uniform traffic matrix under the hose model.

  19. WDM-CAP-PON integration with VLLC system based on optical frequency comb

    Science.gov (United States)

    He, Jing; Dong, Huan; Deng, Rui; Shi, Jin; Chen, Lin

    2016-09-01

    In this paper, a wavelength division multiplexing carrier-less amplitude phase modulation passive optical network (WDM-CAP-PON) integration with visible laser light communication (VLLC) system is proposed and experimentally demonstrated. To reduce the cost of WDM system, the optical frequency comb scheme using one Mach-Zehnder modulator (MZM) is utilized and five flat optical combs can be generated. Meanwhile, a blue laser diode (LD) as a VLLC optical source can provide high data rate and long transmission distance. Utilizing overlap frequency domain equalization (OFDE) and negative chirp of MZM, the system performance in both Q-factor and receiver sensitivity can be improved. After 20 km standard single mode fiber (SSMF) and 4.5 m free space transmission, the experimental results show that 10 Gb/s CAP signal can be achieved under 7% forward error correction (FEC) limit of 3 . 8 × 10-3.

  20. All-optical code routing in interconnected optical CDMA and WDM ring networks.

    Science.gov (United States)

    Deng, Yanhua; Fok, Mable P; Prucnal, Paul R; Wang, Ting

    2010-11-01

    We propose an all-optical hybrid network composed of optical code division multiple access (CDMA) rings interconnecting through a reconfigurable wavelength division multiplexing (WDM) metro area ring. This network retains the advantages of both the optical CDMA and WDM techniques, including asynchronous access and differentiated quality of service, while removing the hard limit on the number of subscribers and increasing network flexibility. The all-optical network is enabled by using nonlinear optical loop mirrors in an add/drop router (ADR) that performs code conversion, dropping, and switching asynchronously. We experimentally demonstrate the functionalities of the ADR in the proposed scheme asynchronously and obtain error-free performance. The bit-error rate measurements show acceptable power penalties for different code routes.

  1. A hybrid WDM transport system based on mutually injection-locked Fabry Perot laser diodes

    Science.gov (United States)

    Ying, Cheng-Ling; Lu, Hai-Han; Tzeng, Shah-Jye; Ma, Hsien-Li; Chuang, Yao-Wei

    2007-08-01

    A hybrid wavelength-division-multiplexing (WDM) transport system based on mutually injection-locked Fabry-Perot laser diodes (FP LDs) for CATV, 256-QAM and OC-48 transmission is proposed and demonstrated. Mutually injection-locked FP LDs as broadband light source could be relatively simple and cost-effective compared with other demonstrated light source schemes. The proposed hybrid WDM transport system employs four filtered wavelengths (modes) to transmit 111 AM-VSB channels, four 256-QAM digital passband channels, and one OC-48 digital baseband channel simultaneously. Since our proposed system does not use multiple distributed feedback (DFB) LDs, it reveals a prominent one with simpler and more economic advantages.

  2. Combined Optical and Electrical Spectrum Shaping for High-Baud-Rate Nyquist-WDM Transceivers

    DEFF Research Database (Denmark)

    Porto da Silva, Edson; Borkowski, Robert; Preussler, Stefan;

    2016-01-01

    bandwidth is related to the optical comb parameters 25 and the pulse shaping of the modulating waveforms in the electrical domain. Such de- 26 pendence may result in broadening of the modulated spectra, which can degrade the 27 performance of Nyquist-WDM systems due to interchannel crosstalk penalties....... However, 28 it is shown and experimentally demonstrated that the same technique of optical pulse 29 train generation can be allied with digital pulse shaping to improve the confinement of 30 the modulated spectrum toward the Nyquist limit independently of the number of OTDM 31 tributaries used....... To investigate the benefits of the proposed approach, we demonstrate 32 the first WDM Nyquist-OTDM signal generation based on the periodic train of sinc pulses 33 and electrical spectrum shaping. Straight line transmission of five 112.5-Gbd Nyquist- 34 OTDM dual-polarization quadrature phase-shift keying (QPSK...

  3. Improved optical performance monitoring technique based on nonlinear optics for high-speed WDM Nyquist systems

    Science.gov (United States)

    Guesmi, Latifa; Menif, Mourad

    2016-04-01

    The field of fiber optics nonlinearity is more discussed last years due to such remarkable enhancement in the nonlinear processes efficiency. In this paper, and for optical performance monitoring (OPM), a new achievement of nonlinear effects has been investigated. The use of cross-phase modulation (XPM) and four-wave mixing (FWM) effects between input optical signal and inserted continuous-wave probe has proposed for impairments monitoring. Indeed, transmitting a multi-channels phase modulated signal at high data rate (1 Tbps WDM Nyquist NRZ- DP-QPSK) improves the sensitivity and the dynamic range monitoring. It was observed by simulation results that various optical parameters including optical power, wavelength, chromatic dispersion (CD), polarization mode dispersion (PMD), optical signal-to-noise ratio (OSNR), Q-factor and so on, can be monitored. Also, the effect of increasing the channel spacing between WDM signals is studied and proved its use for FWM power monitoring.

  4. Research on WDM optical fiber transmission system based on fiber Raman amplifier

    Institute of Scientific and Technical Information of China (English)

    Fei Xue(薛飞); Kun Qiu(邱昆); Yue Chen(陈玥)

    2003-01-01

    After wavelength division multiplexing (WDM) optical fiber transmission system based on fiber Raman amplifier (FRA) is investigated in detail, the influence of the collocation of dispersion compensation fiber (DCF), the dispersion coefficient, dispersion slope (DS), effective core area, nonlinear index, length of FRA, launch power and the bandwidth of Bessel filter on bit error rate (BER) is deduced. The influence of Rayleigh backscattering noise on optical signal noise ratio (OSNR) is also investigated, which affects the performance of long haul transmission badly. The result indicates that the broadband long haul transmission can be realized through the reasonable design of the fiber. The result is useful to the optimal design of the WDM optical fiber transmission system based on FRA.

  5. A Grooming Nodes Optimal Allocation Method for Multicast in WDM Networks

    Directory of Open Access Journals (Sweden)

    Chengying Wei

    2016-01-01

    Full Text Available The grooming node has the capability of grooming multicast traffic with the small granularity into established light at high cost of complexity and node architecture. In the paper, a grooming nodes optimal allocation (GNOA method is proposed to optimize the allocation of the grooming nodes constraint by the blocking probability for multicast traffic in sparse WDM networks. In the proposed GNOA method, the location of each grooming node is determined by the SCLD strategy. The improved smallest cost largest degree (SCLD strategy is designed to select the nongrooming nodes in the proposed GNOA method. The simulation results show that the proposed GNOA method can reduce the required number of grooming nodes and decrease the cost of constructing a network to guarantee a certain request blocking probability when the wavelengths per fiber and transmitter/receiver ports per node are sufficient for the optical multicast in WDM networks.

  6. Capacity and capability enhancements of FBG sensor system by utilizing intensity and WDM detection technique

    Science.gov (United States)

    Yeh, Chien-Hung; Zhuang, Yuan-Hong; Tsai, Ning; Chow, Chi-Wai

    2017-03-01

    In this paper, we demonstrate a multipoint fiber Bragg grating (FBG)-based sensor system by using intensity and wavelength-division-multiplexing (I-WDM) technique to enhance the sensing capacity and capability. In the proposed multipoint sensor system, a three output port optical splitter with different output ratios of 50%, 35% and 15% is proposed to connect each intensity coding FBG sensor for strain and temperature sensing simultaneously. Different output ratios of connected ports can produce different intensity-coding for I-WDM application. Nine FBGs with different Bragg wavelengths are employed for demonstration. The proposed FBG sensor system not only can sense the strain and temperature simultaneously, but also can increase the capacity and capability.

  7. Novel scheme enabling broadcast signal transmission in WDM passive optical network

    Institute of Scientific and Technical Information of China (English)

    Xuejiao Ma; Chaoqin Gan

    2011-01-01

    @@ We present a novel method for providing broadcast signal transmission in a wavelength division multiplex-ing passive optical network (WDM-PON).An unmodulated optical carrier for downstream transmission and a pair of unmodulated single-side band subcarriers are utilized for broadcast delivery and upstream transmission, respectively.System performance at 2.5-Gb/s downlupstream and 2.5-Gb/s broadcast trans-mission is also investigated.%We present a novel method for providing broadcast signal transmission in a wavelength division multiplexing passive optical network (WDM-PON).An unmodulated optical carrier for downstream transmission and a pair of unmodulated single-side band subcarriers are utilized for broadcast delivery and upstream transmission, respectively.System performance at 2.5-Gb/s down/upstream and 2.5-Gb/s broadcast transmission is also investigated.

  8. Performance analysis of cross-seeding WDM-PON system using transfer matrix method

    Science.gov (United States)

    Simatupang, Joni Welman; Pukhrambam, Puspa Devi; Huang, Yen-Ru

    2016-12-01

    In this paper, a model based on the transfer matrix method is adopted to analyze the effects of Rayleigh backscattering and Fresnel multiple reflections on a cross-seeding WDM-PON system. As part of analytical approximation methods, this time-independent model is quite simple but very efficient when it is applied to various WDM-PON transmission systems, including the cross-seeding scheme. The cross seeding scheme is most beneficial for systems with low loop-back ONU gain or low reflection loss at the drop fiber for upstream data in bidirectional transmission. However for downstream data transmission, multiple reflections power could destroy the usefulness of the cross-seeding scheme when the reflectivity is high enough and the RN is positioned near OLT or close to ONU.

  9. Compton scattering measurements from dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Glenzer, S H; Neumayer, P; Doeppner, T; Landen, L; Lee, R W; Wallace, R; Weber, S; Lee, H J; Kritcher, A L; Falcone, R; Regan, S P; Sawada, H; Meyerhofer, D D; Gregori, G; Fortmann, C; Schwarz, V; Redmer, R

    2007-10-02

    Compton scattering has been developed for accurate measurements of densities and temperatures in dense plasmas. One future challenge is the application of this technique to characterize compressed matter on the National Ignition Facility where hydrogen and beryllium will approach extremely dense states of matter of up to 1000 g/cc. In this regime, the density, compressibility, and capsule fuel adiabat may be directly measured from the Compton scattered spectrum of a high-energy x-ray line source. Specifically, the scattered spectra directly reflect the electron velocity distribution. In non-degenerate plasmas, the width provides an accurate measure of the electron temperatures, while in partially Fermi degenerate systems that occur in laser-compressed matter it provides the Fermi energy and hence the electron density. Both of these regimes have been accessed in experiments at the Omega laser by employing isochorically heated solid-density beryllium and moderately compressed beryllium foil targets. In the latter experiment, compressions by a factor of 3 at pressures of 40 Mbar have been measured in excellent agreement with radiation hydrodynamic modeling.

  10. Compton scattering measurements from dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Glenzer, S H; Neumayer, P; Doeppner, T; Landen, O L; Lee, R W; Wallace, R J; Weber, S [Lawrence Livermore National Laboratory, Livermore, CA (United States); Lee, H J; Kritcher, A L; Falcone, R [University of California Berkeley, Berkeley, CA 94709 (United States); Regan, S P; Sawada, H; Meyerhofer, D D [Laboratory for Laser Energetics, Rochester, NY (United States); Gregori, G [Clarendon Laboratory, University of Oxford, Oxford OX1 3PU (United Kingdom); Fortmann, C; Schwarz, V; Redmer, R [Institut fuer Physik, Universitaet Rostock, D-18051 Rostock (Germany)], E-mail: glenzer1@llnl.gov

    2008-05-15

    Compton scattering techniques have been developed for accurate measurements of densities and temperatures in dense plasmas. One future challenge is the application of this technique to characterize compressed matter on the National Ignition Facility where hydrogen and beryllium will approach extremely dense states of matter of up to 1000 g/cc. In this regime, the density, compressibility, and capsule fuel adiabat may be directly measured from the Compton scattered spectrum of a high-energy x-ray line source. Specifically, the scattered spectra directly reflect the electron velocity distribution. In non-degenerate plasmas, the width provides an accurate measure of the electron temperatures, while in partially Fermi degenerate systems that occur in laser-compressed matter it provides the Fermi energy and hence the electron density. Both of these regimes have been accessed in experiments at the Omega laser by employing isochorically heated solid-density beryllium and moderately compressed beryllium foil targets. In the latter experiment, compressions by a factor of 3 at pressures of 40 Mbar have been measured in excellent agreement with radiation hydrodynamic modeling.

  11. Dense Suspension Splash

    Science.gov (United States)

    Zhang, Wendy; Dodge, Kevin M.; Peters, Ivo R.; Ellowitz, Jake; Klein Schaarsberg, Martin H.; Jaeger, Heinrich M.

    2014-03-01

    Upon impact onto a solid surface at several meters-per-second, a dense suspension plug splashes by ejecting liquid-coated particles. We study the mechanism for splash formation using experiments and a numerical model. In the model, the dense suspension is idealized as a collection of cohesionless, rigid grains with finite surface roughness. The grains also experience lubrication drag as they approach, collide inelastically and rebound away from each other. Simulations using this model reproduce the measured momentum distribution of ejected particles. They also provide direct evidence supporting the conclusion from earlier experiments that inelastic collisions, rather than viscous drag, dominate when the suspension contains macroscopic particles immersed in a low-viscosity solvent such as water. Finally, the simulations reveal two distinct routes for splash formation: a particle can be ejected by a single high momentum-change collision. More surprisingly, a succession of small momentum-change collisions can accumulate to eject a particle outwards. Supported by NSF through its MRSEC program (DMR-0820054) and fluid dynamics program (CBET-1336489).

  12. DENSE MEDIUM CYCLONE OPTIMIZATON

    Energy Technology Data Exchange (ETDEWEB)

    Gerald H. Luttrell; Chris J. Barbee; Peter J. Bethell; Chris J. Wood

    2005-06-30

    Dense medium cyclones (DMCs) are known to be efficient, high-tonnage devices suitable for upgrading particles in the 50 to 0.5 mm size range. This versatile separator, which uses centrifugal forces to enhance the separation of fine particles that cannot be upgraded in static dense medium separators, can be found in most modern coal plants and in a variety of mineral plants treating iron ore, dolomite, diamonds, potash and lead-zinc ores. Due to the high tonnage, a small increase in DMC efficiency can have a large impact on plant profitability. Unfortunately, the knowledge base required to properly design and operate DMCs has been seriously eroded during the past several decades. In an attempt to correct this problem, a set of engineering tools have been developed to allow producers to improve the efficiency of their DMC circuits. These tools include (1) low-cost density tracers that can be used by plant operators to rapidly assess DMC performance, (2) mathematical process models that can be used to predict the influence of changes in operating and design variables on DMC performance, and (3) an expert advisor system that provides plant operators with a user-friendly interface for evaluating, optimizing and trouble-shooting DMC circuits. The field data required to develop these tools was collected by conducting detailed sampling and evaluation programs at several industrial plant sites. These data were used to demonstrate the technical, economic and environmental benefits that can be realized through the application of these engineering tools.

  13. Adding new components to the knowledge plane GMPLS over WDM networks

    OpenAIRE

    Urra i Fàbregas, Anna; Calle Ortega, Eusebi; Marzo i Lázaro, Josep Lluís

    2004-01-01

    A recent study defines a new network plane: the knowledge plane. The incorporation of the knowledge plane over the network allows having more accurate information of the current and future network states. In this paper, the introduction and management of the network reliability information in the knowledge plane is proposed in order to improve the quality of service with protection routing algorithms in GMPLS over WDM networks. Different experiments prove the efficiency and scalability of the...

  14. Increasing the cost-constrained availability of WDM Networks with Degree-3 Structured Topologies

    DEFF Research Database (Denmark)

    Gutierrez Lopez, Jose Manuel; Georgakilas, Kostas; Katrinis, Kostas;

    2010-01-01

    This paper studies the impact of node degree distribution to availability and capital and deployment expenditure of optical WDM transport networks. Three structured degree-3 graphs with fair node degree distribution are proposed in this context. Using a realistic network optimization framework...... based on genetic algorithms, we evaluate the performance of structured topologies and compare it against a practical topology (NSFNET). The results manifest that nodal degree fairness leads to increased availability compared to conventional topologies, while not incurring higher capital and deployment...

  15. 5490km Ultra Long Haul WDM System%5490km超长距离WDM系统

    Institute of Scientific and Technical Information of China (English)

    王加莹; 周伟勤; 施社平

    2004-01-01

    An ultra long haul WDM (ULWDM) system in ZTE China is introduced in this report, whose transmission distance has been extended to 5490km, with 50GHz channel spacing in a bandwidth of 75nm in C and L bands. The structure and techniques of the commercial equipment and experiment facilities are introduced.Some important techniques - RZ modulation, distributed amplification, and automatic control--in this system are introduced. Some test results are described as well.

  16. Stimulated Raman Effect in Bi—driectionally Amplified and Transmission WDM Systems

    Institute of Scientific and Technical Information of China (English)

    KanZHANG; AnshiXU

    1997-01-01

    One of the nonlinear effect-SRS effect in bi-directional WDM transmission systems is studied in this paper,Analytical and numerical results are given to show the effect of SRS.Systems with uni-and bi-directional EDFAs(Erbium doped fiber amplifiers0 are also considered.And a new method to deal with SRS effect in bi-directional systems is drawn out.

  17. LED to LED communication with WDM concept for flash light of Mobile phones

    Directory of Open Access Journals (Sweden)

    Devendra J Varanva

    2013-08-01

    Full Text Available After observing recent developments in Free Space Optical Communication especially Visible Light Communication, It is clear that LED is main component as a source. LED being solid state device makes endless list of possibilities. But here we will get through its ability to sense light as well, and use of Wavelength Division Multiplexing (WDM in mobile flash is also suggested, this opens door to many applications.

  18. Load Balancing in WDM Optical Networks with and without Wavelength-Continuity Constraints

    Institute of Scientific and Technical Information of China (English)

    刘逢清; 曾庆济; 杨旭东; 朱栩; 肖石林

    2003-01-01

    In practical optical networks, there is often the same number of wavelengths in a fiber. But if it is notcarefully designed, there will be much difference in link load among different fibers, and unnecessary wavelengthswill be needed. This paper investigated this load balancing issues to minimize the wavelength requirements. BothInteger Linear Programming (ILP) and heuristic algorithms were presented to solve such a problem in WDM opti-cal networks with or without wavelength-continuity constraints.

  19. Corin/Dorin: A WDM-Enabled Platform for Aero-Engine Control Systems

    OpenAIRE

    Xia, Ming; Moslehi, Behzad; Mukherjee, Biswanath; Behbahani, Alireza; Millar, Richard

    2008-01-01

    The Full Authority Digital Electronic Control (FADEC) centralized architecture has become the norm in aero-engine control systems. With a centralized system, changes are costly and complex [1]. The goal of this work is to develop the architectural design concept for a distributed supporting network called Coarse WDM Optical Ring Network (CORIN) appropriate for aero-engine performance monitoring. A CORIN features high bandwidth, reliability, modularity, scalability, flexibility, an...

  20. Study on Loss and Crosstalk in WDM Passive Optical Network Based on Spectral Slicing

    Institute of Scientific and Technical Information of China (English)

    Shaofeng Qiu(邱绍峰); Ge Fan(范戈)

    2003-01-01

    A model for calculating loss and crosstalk in WDM passive optical network based on spectral slicing is proposed in this paper. Through theoretical analysis and numerical calculation, the relationship between loss or crosstalk and the parameters of the system, such as the bandwidth of the light-source, the parameters of the multiplexer, the number of channels and the fraction of channel misalignment, was demonstrated.

  1. Triple functional shared channel in WDM PON by orthogonal modulation and network coding

    Science.gov (United States)

    Lu, Yang; Wei, Yizhen; Hu, Miao; Zhou, Xuefang; Qian, Zhengfeng; Li, Qiliang

    2015-02-01

    A triple functional shared channel in WDM PON is proposed. The channel can be applied for broadcasting, duplex inter-ONU-communication or dynamical bandwidth allocation, increasing the flexibility and the resource utilization of the scheme. The three applications could be achieved by the same hardware, with different software operations. One example scheme is demonstrated. The test results show error free operation is achieved after for the downstream transmission, upstream transmission and the proposed three applications in shared channel after 25 km transmission.

  2. Simultaneous MMW generation and up-conversion for WDM-ROF systems based on FP laser

    Science.gov (United States)

    Zhang, Chan; Ning, TiGang; Li, Jing; Li, Chao; He, Xueqing; Pei, Li

    2016-10-01

    A new wavelength division multiplexing radio-over-fiber (WDM-ROF) scheme based on Fabry-Perot (FP) laser is proposed and demonstrated for simultaneous millimeter-wave (MMW) generation and up-conversion. The tunable optical comb generated by FP laser is served as a cost-effective WDM optical source in central station (CS) and it makes all-optical up-conversion process for all channels simple compared with using a DFB array. All modes from the FP laser are modulated simultaneously by a LiNbO3 Mach-Zehnder modulator (LN-MZM) then. We have systematically compared the performances of MMW generation and up-conversion using LN-MZM based on different modulation schemes. A reflective semiconductor optical amplifiers (RSOA) is used both for the downstream modulation of each channel and for the reduction of mode partition noise (MPN) induced from FP laser. In the scheme, the multiple optical carrier suppression (OCS) modulation shows the highest receiver sensitivity and smallest power penalty over long-distance delivery. In the numerical simulation, 7 WDM channels each carrying 2.5 Gb/s baseband signal have been up-converted to 60 GHz simultaneously with good performance over 25 km single mode fiber (SMF) transmission.

  3. Cost optimal allocation of amplifiers and DCMs in WDM ring networks.

    Science.gov (United States)

    Minagar, Amir; Premaratne, Malin; Tran, An V

    2006-10-30

    Designing metropolitan wavelength division multiplexing (WDM) ring networks with minimum deployment cost is a demanding issue in Telecommunication Network planning . We have already presented amplifier placement methods to minimize the number of amplifiers in WDM rings for the case all amplifiers follow a unique gain model. In this paper, we take into account different types of amplifiers with predefined fixed characteristics and costs. We also formulate fiber dispersion limitations on the ring design, and present two efficient methods for placing amplifiers and Dispersion Compensation Modules (DCMs) in WDM rings to minimize the total deployment cost of the system. The first method deals with both linear and nonlinear equations and uses a mixed integer nonlinear programming (MINLP) solver where the second method applies the linear approximation of nonlinear constraints, and uses a mixed integer linear programming (MILP) solver to minimize the total cost of the system. We carry out Simulation experiments to confirm the applicability of the methods and compare the results for various network configurations.

  4. Nyquist WDM superchannel using offset-16QAM and receiver-side digital spectral shaping.

    Science.gov (United States)

    Xiang, Meng; Fu, Songnian; Tang, Ming; Tang, Haoyuan; Shum, Perry; Liu, Deming

    2014-07-14

    The performance of Nyquist WDM superchannel using advanced modulation formats with coherent detection is degraded due to the existence of both inter-symbol interference (ISI) and inter-channel interference (ICI). Here, we propose and numerically investigate a Nyquist WDM superchannel using offset-16QAM and receiver-side digital spectral shaping (RS-DSS), achieving a spectral efficiency up to 7.44 bit/s/Hz with 7% hard-decision forward error correction (HD-FEC) overhead. Compared with Nyquist WDM superchannel using 16QAM and RS-DSS, the proposed system has 1.4 dB improvement of required OSNR at BER = 10(-3) in the case of back-to-back (B2B) transmission. Furthermore, the range of launched optical power allowed beyond HD-FEC threshold is drastically increased from -6 dBm to 1.2 dBm, after 960 km SSMF transmission with EDFA-only. In particular, no more than 1.8 dB required OSNR penalty at BER = 10(-3) is achieved for the proposed system even with the phase difference between channels varying from 0 to 360 degree.

  5. A CLS-based survivable and energy-saving WDM-PON architecture

    Science.gov (United States)

    Zhu, Min; Zhong, Wen-De; Zhang, Zhenrong; Luan, Feng

    2013-11-01

    We propose and demonstrate an improved survivable and energy-saving WDM-PON with colorless ONUs. It incorporates both energy-saving and self-healing operations. A simple effective energy-saving scheme is proposed by including an energy-saving control unit in the OLT and a control unit at each ONU. The energy-saving scheme realizes both dozing and sleep (offline) modes, which greatly improves the energy-saving efficiency for WDM-PONs. An intelligent protection switching scheme is designed in the OLT, which can distinguish if an ONU is in dozing/sleep (offline) state or a fiber is faulty. Moreover, by monitoring the optical power of each channel on both working and protection paths, the OLT can know the connection status of every fiber path, thus facilitating an effective protection switching and a faster failure recovery. The improved WDM-PON architecture not only significantly reduces energy consumption, but also performs self-healing operation in practical operation scenarios. The scheme feasibility is experimentally verified with 10 Gbit/s downstream and 1.25 Gbit/s upstream transmissions. We also examine the energy-saving efficiency of our proposed energy-saving scheme by simulation, which reveals that energy saving mainly arises from the dozing mode, not from the sleep mode when the ONU is in the online state.

  6. Constraining the nature of dark matter with the star formation history of the faintest Local Group dwarf galaxy satellites

    CERN Document Server

    Chau, Alice; Governato, Fabio

    2016-01-01

    $\\Lambda$-Warm Dark Matter (WDM) has been proposed as alternative scenario to $\\Lambda$ cold dark matter (CDM), motivated by discrepancies at the scale of dwarf galaxies, with less small-scale power and realized by collisionless particles with energies in the range $1-3$ keV. We present a new approach to constrain the viability of such WDM models using star formation histories of the dwarf spheroidal galaxies (dSphs) in the Local Group. We compare their high time-resolution star formation histories (SFHs) obtained with HST-based color magnitude diagrams with the range of possible collapse redshifts of their dark matter halos expected in CDM and in different WDM scenarios. The collapse redshift is inferred after determining a plausible infall mass of the subhalo. This is based on the current mass of individual dwarf inferred from stellar kinematics combined with results of cosmological simulations providing information on the subhalo evolution. Since WDM subhalos close to the filtering mass scale form signific...

  7. The same with less: The cosmic web of warm versus cold dark matter dwarf galaxies

    CERN Document Server

    Reed, Darren S; Smith, Robert E; Potter, Doug; Stadel, Joachim; Moore, Ben

    2014-01-01

    We explore fundamental properties of the distribution of low mass dark matter halos within the cosmic web using warm dark matter (WDM) and cold dark matter (CDM) cosmological simulations. Using self abundance-matched mock galaxy catalogs, we show that the distribution of dwarf galaxies in a WDM universe, wherein low mass halo formation is heavily suppressed, is nearly indistinguishable to that of a CDM universe whose low mass halos are not seen because galaxy formation is suppressed below some threshold halo mass. However, if the scatter between dwarf galaxy luminosity and halo properties is large enough, low mass CDM halos would sometimes host relatively bright galaxies thereby populating CDM voids with the occasional isolated galaxy and reducing the numbers of completely empty voids. Otherwise, without high mass to light scatter, all mock galaxy clustering statistics that we consider--the auto-correlation function, the numbers and radial profiles of satellites, the numbers of isolated galaxies, and the PDF ...

  8. Fingerprints of the initial conditions on the density profiles of cold and warm dark matter haloes

    CERN Document Server

    Polisensky, E

    2015-01-01

    We use N-body simulations of dark matter haloes in cold dark matter (CDM) and a large set of different warm dark matter (WDM) cosmologies to demonstrate that the spherically averaged density profile of dark matter haloes has a shape that depends on the power spectrum of matter perturbations. Density profiles are steeper in WDM but become shallower at scales less than one percent of the virial radius. Virialization isotropizes the velocity dispersion in the inner regions of the halo but does not erase the memory of the initial conditions in phase space. The location of the observed deviations from CDM in the density profile and in phase space can be directly related to the ratio between the halo mass and the filtering mass and are most evident in small mass haloes, even for a 34 keV thermal relic WDM. The rearrangement of mass within the haloes supports analytic models of halo structure that include angular momentum. We also find evidence of a dependence of the slope of the inner density profile in CDM cosmolo...

  9. Warm dark matter signatures on the 21cm power spectrum: Intensity mapping forecasts for SKA

    CERN Document Server

    Carucci, Isabella P; Viel, Matteo; Lapi, Andrea

    2015-01-01

    We investigate the impact that warm dark matter (WDM) has in terms of 21cm intensity mapping in the post-reionization Universe at z = 3 - 5. We perform hydrodynamic simulations for 5 different models: cold dark matter and WDM with 1,2,3,4 keV (thermal relic) mass and assign the neutral hydrogen a-posteriori using two different methods that both reproduce observations in terms of column density distribution function of neutral hydrogen systems. Contrary to naive expectations, the suppression of power present in the linear and non-linear matter power spectra, results in an increase of power in terms of neutral hydrogen and 21cm power spectra. This is due to the fact that there is a lack of small mass halos in WDM models with respect to cold dark matter: in order to distribute a total amount of neutral hydrogen within the two cosmological models, a larger quantity has to be placed in the most massive halos, that are more biased compared to the cold dark matter cosmology. We quantify this effect and address signi...

  10. Performance of Thin-Film as Wavelength Filter in Wdm-Pof Network

    Directory of Open Access Journals (Sweden)

    Mohd S.A. Rahman

    2012-01-01

    Full Text Available Problem statement: Huge capacity for data transmission and bandwidth are becoming a need nowadays. High cost of implementation using optical fibers prevents utilization of the technology as wide as possible. Approach: Wavelength Division Multiplexing (WDM was a technique that offers the solution for providing better bandwidth. WDM technique allows several signals that have different wavelengths to be transmitted in a single optical fiber to the receiver without any external interference or internal interruption between the signals transmitted simultaneously. WDM technique requires splitting of signals at reaching the receivers and one of the solutions presented in this study will provide a method using inexpensive filtering device that functions efficiently as a demultiplexer that can be develop without any complication. There were a lot of systems that provided demultiplexing techniques in the industry; all the systems are expensive to be implemented. Here the study provides an effective and easy to construct demultiplexer by using colored thin films. The WDM-POF system studies the performances of thin-films to be used as demultiplexer and red thin-films will be focused. Results: In theory, the thin-films will filter out any undesired signals that pass through the fiber and the desired signal will be carried to the end-receiver. The effectiveness of each red thin- films were characterized by analyzing the insertion losses (dBm and power output (µW. Characterization analysis in this study includes the characterization test of using the same sources towards different types of red thin-films to obtain the best film that could filter out any undesired wavelength and let only the desired wavelength to be transmitted at high percentage. An initial stage of selecting different colored films by analyzing the energy spectrum distribution curves for the potential red thin- films will then be characterized where red, blue and green LED sources were

  11. Impact of Rayleigh backscattering on single/dual feeder fiber WDM-PON architectures based on array waveguide gratings

    Institute of Scientific and Technical Information of China (English)

    Muhammad Idrees AFRIDI; Jie ZHANG; Yousaf KHAN; Jiawei HAN; Aftab HUSSEIN; Shahab AHMAD

    2013-01-01

    The performance of colorless wavelength- division multiplexing passive optical network (WDM- PON) systems suffers from transmission impairments due to Rayleigh backscattering (RB). A single feeder fiber colorless WDM-PON architecture was modeled, simulated and analyzed at 25 km distance that sustained the noise induced by RB. We analytically compared the performances between single feeder and dual feeder WDM-PON architectures based on array waveguide gratings (AWGs). For single feeder WDM-PON, the high extinction ratios in both return-to-zeros (RZ)-shaped differential phase shift keying (DPSK) downstream and intensity remodulated upstream data signals helped to increase the tolerance to the noise induced by RB. However, a cost effective colorless system in dual feeder WDM-PON architecture was achieved without any optical amplification and dispersion compensation, low power penalty. These results illustrate that single feeder fiber architecture was cost effective in terms of deployment having a power penalty, while dual feeder fiber had lower power penalty thereby with better performance. Simulation results show that downstream and upstream signals achieved error-free performance at 10-Gbps with negligible penalty and enhanced tolerance to the noise induced by RB over 25 km single mode fiber.

  12. 16×10 Gb/s WDM bidirectional gating in a semiconductor optical amplifier for optical cross connects exploiting network connection symmetry

    DEFF Research Database (Denmark)

    Yu, Jianjun; Buxens Azcoaga, Alvaro Juan; Clausen, Anders;

    2000-01-01

    In order to further reduce the number of gating elements in space switches, the performance of 10 Gb/s wavelength division multiplexing (WDM) bidirectional semiconductor optical amplifier (SOA) gating is investigated, We demonstrate for the first time that a conventional SOA can be used for bidir...... for bidirectional WDM gating operation at 10 Gb/s by the use of holding light injection...

  13. One-to-six WDM multicasting of DPSK signals based on dual-pump four-wave mixing in a silicon waveguide

    DEFF Research Database (Denmark)

    Pu, Minhao; Hu, Hao; Ji, Hua

    2011-01-01

    We present WDM multicasting based on dual-pump four-wave mixing in a 3-mm long dispersion engineered silicon waveguide. One-to-six phase-preserving WDM multicasting of 10-Gb/s differential phase-shiftkeying (DPSK) data is experimentally demonstrated with bit-error rate measurements. All the six...

  14. Design of dual ring wavelength filters for WDM applications

    Science.gov (United States)

    Sathyadevaki, R.; Shanmuga sundar, D.; Sivanantha Raja, A.

    2016-12-01

    Wavelength division multiplexing plays a prime role in an optical communication due to its advantages such as easy network expansion, longer span lengths etc. In this work, photonic crystal based filters with the dual rings are proposed which act as band pass filters (BPF) and channel drop filter (CDF) that has found a massive applications in C and L-bands used for wavelength selection and noise filtering at erbium doped fiber amplifiers and dense wavelength division multiplexing operation. These filters are formulated on the square lattice with crystal rods of silicon material of refractive index 3.4 which are perforated on an air of refractive index 1. Dual ring double filters (band pass filter and channel drop filter) on single layout possess passing and dropping band of wavelengths in two distinct arrangements with entire band quality factors of 92.09523 & 505.263 and 124.85019 & 456.8633 for the pass and drop filters of initial setup and amended setup respectively. These filters have the high-quality factor with broad and narrow bandwidths of 16.8 nm & 3.04 nm and 12.85 nm & 3.3927 nm. Transmission spectra and band gap of the desired filters is analyzed using Optiwave software suite. Two dual ring filters incorporated on a single layout comprises the size of 15×11 μm which can also be used in the integrated photonic chips for the ultra-compact unification of devices.

  15. Conductive dense hydrogen

    Science.gov (United States)

    Eremets, M.; Troyan, I.

    2012-12-01

    Hydrogen at ambient pressures and low temperatures forms a molecular crystal which is expected to display metallic properties under megabar pressures. This metal is predicted to be superconducting with a very high critical temperature Tc of 200-400 K. The superconductor may potentially be recovered metastably at ambient pressures, and it may acquire a new quantum state as a metallic superfluid and a superconducting superfluid. Recent experiments performed at low temperatures T 220 GPa, new Raman modes arose, providing evidence for the transformation to a new opaque and electrically conductive phase IV. Above 260 GPa, in the next phase V, hydrogen reflected light well. Its resistance was nearly temperature-independent over a wide temperature range, down to 30 K, indicating that the hydrogen was metallic. Releasing the pressure induced the metallic phase to transform directly into molecular hydrogen with significant hysteresis at 200 GPa and 295 K. These data were published in our paper: M. I. Eremets and I. A. Troyan "Conductive dense hydrogen." Nature Materials 10: 927-931. We will present also new results on hydrogen: phase diagram with phases IV and V determined in P,T domain up to 300 GPa and 350 K. We will also discuss possible structures of phase IV based on our Raman and infrared measurements up to 300 GPa.

  16. Dense Hypervelocity Plasma Jets

    Science.gov (United States)

    Case, Andrew; Witherspoon, F. Douglas; Messer, Sarah; Bomgardner, Richard; Phillips, Michael; van Doren, David; Elton, Raymond; Uzun-Kaymak, Ilker

    2007-11-01

    We are developing high velocity dense plasma jets for fusion and HEDP applications. Traditional coaxial plasma accelerators suffer from the blow-by instability which limits the mass accelerated to high velocity. In the current design blow-by is delayed by a combination of electrode shaping and use of a tailored plasma armature created by injection of a high density plasma at a few eV generated by arrays of capillary discharges or sparkgaps. Experimental data will be presented for a complete 32 injector gun system built for driving rotation in the Maryland MCX experiment, including data on penetration of the plasma jet through a magnetic field. We present spectroscopic measurements of plasma velocity, temperature, and density, as well as total momentum measured using a ballistic pendulum. Measurements are in agreement with each other and with time of flight data from photodiodes and a multichannel PMT. Plasma density is above 10^15 cm-3, velocities range up to about 100 km/s. Preliminary results from a quadrature heterodyne HeNe interferometer are consistent with these results.

  17. Building new WDM regulations for the Namibian tourism sector on factors influencing current water-management practices at the enterprise level

    Science.gov (United States)

    Schachtschneider, Klaudia

    Namibia’s aridity is forcing its water sector to resort to new water resource management approaches, including water demand management (WDM). Such a change in management approach is facilitated through the country’s opportunity at independence to rewrite and adapt its old policies, including those for water and tourism. Legal support for WDM through the Water Act and other sector-specific Acts is crucial to plan the practical implementation of WDM throughout the different water use sectors of Namibia. In order to be able to put the policy into practice, it is imperative to understand which factors motivate people to adopt WDM initiatives. Within the Namibian tourism industry three main factors have been identified which influence the water-management approaches at tourist facilities. This paper discusses how the water and tourism decision makers can consider these factors when developing new regulations to introduce WDM in the tourism sector.

  18. Single fiber colorless symmetric WDM-PON architecture using time interleaved remodulation technique for mitigating Rayleigh backscattering resilience

    Science.gov (United States)

    Afridi, Muhammad Idrees; Zhang, Jie; Zhao, Yong-li; Latif, Abdul; Niazi, Shahab Ahmed

    2013-01-01

    A time interleaved differential phase shift keying (DPSK) remodulation technique is proposed to mitigate the effect of Rayleigh backscattering (RBS)-induced noise in a single fiber colorless wavelength-division-multiplexing passive optical network (WDM-PON). In order to achieve a cost effective optical network unit (ONU) solution without dedicated laser sources for upstream signals to provide optimum symmetric capacity in a colorless WDM-PON, remodulation becomes the core attraction. Also as the performance of colorless WDM-PON systems suffers from the transmission impairments due to RBS, it is mitigated by using this remodulation scheme. Simulation results show that downstream and upstream signals achieve the error-free performance at 10 Gbit/s with negligible penalty, and enhance the tolerance to RBS-induced noise over a 25 km single-mode fiber.

  19. Performance Analysis of WDM-PON System Based on Optimized Remotely Pumped Erbium-Doped Fiber Amplifier (EDFA) Parameter

    Science.gov (United States)

    Ahmed, N.; Fadhil, Hilal A.; Aljunid, S. A.; Sharafat Ali, Md.; Rahman, Matiur

    2015-06-01

    In this paper, the performance of wavelength division multiplexing-passive optical network (WDM-PON) system using the erbium-doped fiber amplifier (EDFA) is optimized and evaluated. The optimization is analyzed by finding the EDFA length range at which the output power produced are the highest and the pump power range at which the gain flatness produced are within the effective range (0.3 dB). After the optimization process, the optimized EDFA system produces the gain of 26.6±0.292 dB, noise figure of 3.82 dB and output power of 7 dBm and the system is then implemented into WDM system. The performance of WDM system is compared against the system without EDFA in terms of bit error rate (BER). Results obtained prove that the proposed system with the EDFA consistently performs better than the conventional system.

  20. 基于FP激光器设计WDM-PON光源低成本ONU光源理论浅析

    Institute of Scientific and Technical Information of China (English)

    陈茜

    2006-01-01

    @@ 在设计WDM-PON系统时,ONU端光源是其关键技术之一,传统的ONU光源价格比较昂贵而且较易受环境以及温度的影响,本文提出了一种新型WDM-PON的ONU光源和一个采用了该光源的WDM-PON系统结构,并对光源的性能进行了研究.这种光源是通过向FP激光二极管注入窄带ASE来实现的,并且该二极管无需冷却器和隔离器.

  1. Employing injection-locked FP LDs to set up a hybrid CATV/MW/MMW WDM light wave transmission system.

    Science.gov (United States)

    Lin, Chun-Yu; Lu, Hai-Han; Li, Chung-Yi; Wu, Po-Yi; Peng, Peng-Chun; Jhang, Tai-Wei; Lin, Che-Yu

    2014-07-01

    A hybrid cable television (CATV)/microwave (MW)/millimeter-wave (MMW) wavelength-division-multiplexing (WDM) light wave transmission system based on injection-locked Fabry-Perot laser diodes (FP LDs) is proposed and demonstrated. Different from conventional hybrid WDM light wave transmission systems, which need wavelength-selected distributed feedback laser diodes to support various services, the proposed systems employ injection-locked FP LDs to provide multiple applications. Over a 40 km single-mode fiber transport, impressive performances of carrier-to-noise ratio/composite second-order/composite triple-beat/bit error rate are obtained for 550 MHz CATV/20 GHz MW/40 GHz MMW/60 GHz MMW signal transmissions. Such a hybrid WDM light wave transmission system would be attractive for fiber links to provide broadband integrated services.

  2. 10-Gb/S Transmission of Wdm Pon for Man with 50km Reach Based On Ftth

    Directory of Open Access Journals (Sweden)

    Ankit bagga

    2014-08-01

    Full Text Available The wavelength-division-multiplexed passive optical network (WDM-PON is considered to be the next evolutionary solution for a simplified and future-proofed access system that can accommodate exponential traffic growth and bandwidth-hungry new applications. WDM-PON mitigates the complicated time-sharing and power budget issues in time division- multiplexed PON (TDM-PON by providing virtual point-to-point optical connectivity to multiple end users through a dedicated pair of wavelengths. The objective of this paper is proposed a scheme for metropolitan area networks comprising optical components based on arrayed waveguide grating multiplexers, demultiplexers .The Arrayed waveguide gratings based multiplexers and demultiplexers for WDM applications prove to be capable of precise multiplexing and demultiplexing of a large number of channels with relatively low losses.

  3. Transmission of 2.5 Gbit/s Spectrum-sliced WDM System for 50 km Single-mode Fiber

    Science.gov (United States)

    Ahmed, Nasim; Aljunid, Sayed Alwee; Ahmad, R. Badlisha; Fadil, Hilal Adnan; Rashid, Mohd Abdur

    2011-06-01

    The transmission of a spectrum-sliced WDM channel at 2.5 Gbit/s for 50 km of single mode fiber using an system channel spacing only 0.4 nm is reported. We have investigated the system performance using NRZ modulation format. The proposed system is compared with conventional system. The system performance is characterized as the bit-error-rate (BER) received against the system bit rates. Simulation results show that the NRZ modulation format performs well for 2.5 Gbit/s system bit rates. Using this narrow channel spectrum-sliced technique, the total number of multiplexed channels can be increased greatly in WDM system. Therefore, 0.4 nm channel spacing spectrum-sliced WDM system is highly recommended for the long distance optical access networks, like the Metro Area Network (MAN), Fiber-to-the-Building (FTTB) and Fiber-to-the-Home (FTTH).

  4. WDM-PON green access network based on ONU and OLT sleep-wakeup working mode%基于ONU和OLT休眠-唤醒模式的WDM-PON绿色接入网

    Institute of Scientific and Technical Information of China (English)

    林战平

    2015-01-01

    提出了基于ONU和OLT休眠-唤醒节能工作模式的WDM-PON绿色接入网设计.介绍了WDM-PON的节能原理及0LT、ONU的休眠模式和唤醒模式.当休眠模式时间和唤醒模式时间分别设置为20ms和2ms时,每个OLT PON线路卡和ONU家庭路由器可以有效减少约70%的功率消耗.

  5. X-ray scattering as a probe for warm dense mixtures and high-pressure miscibility

    CERN Document Server

    Wünsch, K; Gregori, G; Gericke, D O

    2010-01-01

    We demonstrate the abilities of elastic x-ray scattering to yield information on dense matter with multiple ion species and on the microscopic mixing in dense materials. Based on partial structure factors from ab initio simulations, a novel approach for the elastic scattering feature is applied to dense hydrogen-beryllium and hydrogen-helium mixtures. The scattering signal differs significantly between single species, real microscopic mixtures, and two separate fluids in the scattering volume.

  6. 降低WDM-SCM系统中非线性串扰的研究%Nonlinear Crosstalk Suppression in WDM-SCM Systems

    Institute of Scientific and Technical Information of China (English)

    李孝军; 张明德; 孙小菡

    2002-01-01

    本文首先介绍WDM-SCM光纤通信系统中非线性串扰的产生机理,然后讨论了采用载波互补调制减小串扰的方法,并针对该方法的局限性,提出了一种对称载波互补调制法,该法在高频段上能够将串扰减小10~15 dB.若结合光谱倒置法使用,在降低串扰方面该法可以取得令人满意的效果.

  7. 针对广电的 WDM -PON 网络改造方案%For the WDM-PON Network Construction Scheme

    Institute of Scientific and Technical Information of China (English)

    方权

    2016-01-01

    In the triple play competition, radio and television networks already in awkward position behind, fa-cing three major operators in the electrical erosion, radio and television is an urgent need to a fast and efficient technology to transform the existing network, significantly enhance the network bandwidth, broadband, voice, video, the whole business operation ability.WDM-PON technology which is the combination of the WDM and PON technology advantages, will be a lot of PON signal multiplexing to the same root fiber transmission, do not need to re laying of fiber optic cable, greatly saving fiber resources, reduce construction period, it is suitable for the network transformation of a radio and television.%在三网融合的竞争中,广电网络已经处于落后的尴尬地位,面临着三大运营商的侵蚀,迫切需要一种快速高效的技术来改造现有网络,以大幅提升网络带宽,实现宽带、语音、视频全业务运营。 WDM-PON技术结合WDM和PON技术的优点,将多路PON信号复用到同一根光纤中传输,不需要重新敷设光缆,极大节约了光纤资源,很适合当前的网络改造。

  8. Design and performance evaluation of dynamic wavelength scheduled hybrid WDM/TDM PON for distributed computing applications.

    Science.gov (United States)

    Zhu, Min; Guo, Wei; Xiao, Shilin; Dong, Yi; Sun, Weiqiang; Jin, Yaohui; Hu, Weisheng

    2009-01-19

    This paper investigates the design and implementation of distributed computing applications in local area network. We propose a novel Dynamical Wavelength Scheduled Hybrid WDM/TDM Passive Optical Network, which is termed as DWS-HPON. The system is implemented by using spectrum slicing techniques of broadband light source and overlay broadcast-signaling scheme. The Time-Wavelength Co-Allocation (TWCA) Problem is defined and an effective greedy approach to this problem is presented for aggregating large files in distributed computing applications. The simulations demonstrate that the performance is improved significantly compared with the conventional TDM-over-WDM PON.

  9. Directly-Modulated VCSELs for 2x2 MIMO-OFDM Radio over Fiber in WDM-PON

    DEFF Research Database (Denmark)

    Binti Othman, Maisara; Deng, Lei; Pang, Xiaodan;

    2011-01-01

    We demonstrate directly- modulated VCSELs supporting 2x2 MIMO-OFDM 5.6-GHz radio over fiber signaling over 20-km WDM-PON. Error-free signal demodulation of 64-subcarrier 4-QAM signals modulated at 198.5-Mb/s is achieved after fiber and 2-m indoor wireless transmission.......We demonstrate directly- modulated VCSELs supporting 2x2 MIMO-OFDM 5.6-GHz radio over fiber signaling over 20-km WDM-PON. Error-free signal demodulation of 64-subcarrier 4-QAM signals modulated at 198.5-Mb/s is achieved after fiber and 2-m indoor wireless transmission....

  10. Analysis of the Crosstalk in WDM Systems Caused by Cross-phase Modulation in Erbium-doped Fiber Amplifiers

    Institute of Scientific and Technical Information of China (English)

    LIU Ning; LIAO Changjun; LIU Songhao; GUO Qi; XU Wengchen

    2001-01-01

    The crosstalk in WDM systems caused by cross-phase modulation (XPM) in erbium-doped fiber amplifiers(EDFA) was studied analytically. The results confirm that the EDFA induced phase shift does cause crosstalk in WDM systems. The crosstalk between two channels both with modulated pulse signals is studied for the first time. It was found that the EDFA induced phase shift will cause serious deterioration of the eye diagram when the optical signals continue to travel in the normal-dispersion regime of the transmission fiber, while in the anomalous-dispersion regime this phase shift will not cause much deterioration of the eye diagram.

  11. Bidirectional 120 Gbps SDM-WDM-PON with colourless ONU using 10 Gbps optical components without DSP

    DEFF Research Database (Denmark)

    Hu, Hao; Asif, Rameez; Ye, Feihong

    2016-01-01

    We demonstrate an SDM-WDM-PON system with symmetric aggregated capacity of 120 Gbps (3×scores, 4×wavelengths, 10 Gbps each). The light sources are distributed through the center core of the 7-core fiber, facilitating colorless ONU.......We demonstrate an SDM-WDM-PON system with symmetric aggregated capacity of 120 Gbps (3×scores, 4×wavelengths, 10 Gbps each). The light sources are distributed through the center core of the 7-core fiber, facilitating colorless ONU....

  12. Single-laser 32.5 Tbit/s Nyquist WDM transmission

    CERN Document Server

    Hillerkuss, David; Meyer, Matthias; Wolf, Stefan; Jordan, Meinert; Kleinow, Philipp; Lindenmann, Nicole; Schindler, Philipp C; Melikyan, Argishti; Yang, Xin; Ben-Ezra, Shalva; Nebendahl, Bernd; Dreschmann, Michael; Meyer, Joachim; Parmigiani, Francesca; Petropoulos, Periklis; Resan, Bojan; Oehler, Aandreas; Weingarten, Kurt; Altenhain, Lars; Ellermeyer, Tobias; Moeller, Matthias; Huebner, Michael; Becker, Juergen; Koos, Christian; Freude, Wolfgang; Leuthold, Juerg

    2012-01-01

    We demonstrate 32.5 Tbit/s 16QAM Nyquist WDM transmission over a total length of 227 km of SMF-28 without optical dispersion compensation. A number of 325 optical carriers are derived from a single laser and encoded with dual-polarization 16QAM data using sinc-shaped Nyquist pulses. As we use no guard bands, the carriers have a spacing of 12.5 GHz equal to the Nyquist bandwidth of the data. We achieve a high net spectral efficiency of 6.4 bit/s/Hz using a software-defined transmitter which generates the electrical modulator drive signals in real-time.

  13. Experimental Analysis and Reduction of FWM Using Optical Rectangle Filter for WDM

    Directory of Open Access Journals (Sweden)

    Ghulam Fizza

    2016-01-01

    Full Text Available Nonlinearities implanted by refractive index and scattering degrade the performance of optical networks. In this paper, FWM (Four Wave Mixing has been analyzed for four different channels with 10 nm spacing. Due to the presence of resonant frequency, FWM interface of different channels in WDM (Wavelength Division Multiplexing hinders the performance of the system. The system is affected by nonlinear cross talk. A system with the bandwidth of 10 Gbps has been investigated using External Modulation and an optical rectangle filter as a key parameter to improve the system performance with respect to FWM effect

  14. Eight-wavelength distributed-Bragg-reflector (DBR) laser array transmitter for WDM applications

    Science.gov (United States)

    Fallahi, Mahmoud; McGreer, K. A.; Delage, Andre; Neophytou, A.; Templeton, Ian M.; Champion, Garth; Chatenoud, F.; Barber, Richard A.; Wang, Weijian; He, Jian Jun; Koteles, Emil S.

    1995-03-01

    We report on the design, growth, fabrication and characterization of monolithic wavelength division multiplexed (WDM) laser array transmitter and receiver chips produced by the Canadian Solid State Optoelectronics Consortium. The transmitter chip includes multiple, discrete wavelength, distributed Bragg reflector (DBR) laser diodes monolithically integrated with waveguide combiners fabricated using an InGaAs/GaAs heterostructure. The corresponding wavelength demultiplexer unit is based on a Rowland circle grating spectrometer monolithically integrated with a metal-semiconductor-metal (MSM) detector array fabricated on an InGaAs/AlGaAs/GaAs heterostructure. The epitaxial layer wafers for both transmitter and receiver modules were grown in single molecular beam epitaxy (MBE) runs.

  15. Performance evaluation of modulation formats in 40×40-Gb/s WDM repeaterless transmission systems

    Institute of Scientific and Technical Information of China (English)

    Guangshan Lu; Kun Xu; Jian Wu; Jintong Lin

    2006-01-01

    @@ Transmission performance of six modulation formats is numerically compared in 40 × 40-Gb/s wavelength division multiplexing (WDM) repeaterless systems. The results indicate that return-to-zero differential phase shift keying (RZ-DPSK) (33% duty cycle) demonstrates the best performance among all the formats when the accumulated amplified spontaneous emission power (AASEP) is small. But with the increasing of AASEP, the superiority of RZ-DPSK transmission performance over the other five modulation formats is vanished. AASEP is justified to be the major source for the deterioration of the superiority.

  16. Solving the RWA Problem in WDM Optical Networks Using the BCO Meta-Heuristic

    Directory of Open Access Journals (Sweden)

    V. S. Aćimović-Raspopović

    2010-06-01

    Full Text Available This paper researches the routing and wavelength assignment (RWA problem in wavelength routed optical WDM networks with the wavelength conversion capability at different network nodes. We studied the static case in which all connection requests are known in advance, thus a routing decision can be made based on the complete knowledge of the traffic to be served by the network. The Bee Colony Optimization (BCO metaheuristic is applied to solve the RWA problem. We carried out a comprehensive simulation study of the performance of the proposed BCORWA algorithm for different network topologies and traffic scenarios. The obtained simulation results are analyzed and compared.

  17. Double-link failure protection algorithm for shared sub-path in survivable WDM mesh networks

    Institute of Scientific and Technical Information of China (English)

    Lei Guo(郭磊); Hongfang Yu(虞红芳); Lemin Li(李乐民)

    2004-01-01

    We propose a novel shared sub-path protection (SSPP) algorithm to protect the double-link failures in wavelength division multiplexing (WDM) mesh networks. SSPP segments the primary path into several equal-length sub-paths and searches two link-disjoint backup paths for each sub-path. When computing the paths, SSPP considers the load balance and the resource sharing degree, so that the blocking ratio can be effectively reduced. The simulation results show that SSPP not only can completely protect the double-link failures but also can make the tradeoffs between the resource utilization ratio (or blocking ratio) and the protection-switching time.

  18. Single channel and WDM transmission of 28 Gbaud zero-guard-interval CO-OFDM.

    Science.gov (United States)

    Zhuge, Qunbi; Morsy-Osman, Mohamed; Mousa-Pasandi, Mohammad E; Xu, Xian; Chagnon, Mathieu; El-Sahn, Ziad A; Chen, Chen; Plant, David V

    2012-12-10

    We report on the experimental demonstration of single channel 28 Gbaud QPSK and 16-QAM zero-guard-interval (ZGI) CO-OFDM transmission with only 1.34% overhead for OFDM processing. The achieved transmission distance is 5120 km for QPSK assuming a 7% forward error correction (FEC) overhead, and 1280 km for 16-QAM assuming a 20% FEC overhead. We also demonstrate the improved tolerance of ZGI CO-OFDM to residual inter-symbol interference compared to reduced-guard-interval (RGI) CO-OFDM. In addition, we report an 8-channel wavelength-division multiplexing (WDM) transmission of 28 Gbaud QPSK ZGI CO-OFDM signals over 4160 km.

  19. Remote-seeded WDM-PON upgrade using linear semiconductor opticalamplifiers

    Science.gov (United States)

    Martínez, J. J.; Merayo, N.; Villafranca, A.; Garcés, I.

    2013-05-01

    In this work we have assessed the capacity of a linear (gain-clamped) semiconductor optical amplifier to enhance the budget of WDM PON network links for their evolution from FTTC to FTTH access. A wavelength-seeded network architecture has been considered, evaluating the performance improvement obtained by the use of an amplifier for the cases of link reach extension and optical splitting to reach end users. The evaluation measurements have shown that the extra budget is enough to compensate for the losses of a passive splitter up to atleast 1:16 division rate or to highly increment reach of the network.

  20. Proposal for a novel and simple WDM NRZ-DPSK system

    Institute of Scientific and Technical Information of China (English)

    Yu YU; Xinliang ZHANG; Jose B. ROSAS-FERNANDEZ; Dexiu HUANG; Richard V. PENTY; Ian H. WHITE

    2009-01-01

    A novel and simple non-return-to-zero differential phase shift keying (NRZ-DPSK) wavelength division multiplexing (WDM) system, which can simultaneously demultiplex and demodulate multiple wavelengths, is proposed and investigated in this paper.The phase-to-intensity demodulation principle is based on detuned filtering, which is achieved by using a single commercial array waveguide grating (AWG) in our scheme.By properly choosing appropriate AWG channels at the transmitter, the AWG at the receiver can act as both the demultiplexer and the demodulator of the DPSK signals.Simulations at 10, 20, and 40 Gbit/s show good flexibility and performance for the proposed system.