| 1. |
- Almqvist, Nils, et al.
(författare)
-
AFM and STM characterization of surfaces exposed to high flux deuterium plasma
- 1995
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Ingår i: Journal of Nuclear Materials. - : Elsevier BV. - 0022-3115 .- 1873-4820. ; 220-222:1-3, s. 917-921
-
Tidskriftsartikel (refereegranskat)abstract
- This paper reports the results of scanning tunneling (STM) and atomic force microscopy (AFM) studies of D+ irradiated graphite and graphite-silicon mixtures. The microscopes were used for studying surface topography and for measuring the surface roughness. The substrates were exposed at various temperatures (60 and 700°C) to different doses of deuterium ions in simulators of plasma - surface interactions and in the TEXTOR tokamak. Also nuclear reaction analysis (NRA) and Rutherford backscattering spectroscopy were applied for the qualitative and quantitative determination of surface composition. The initial stages of radiation damage, nanometer-sized bubbles/blisters, were found in plasma-eroded surfaces. These structures only appeared in the graphite phase on the multicomponent material. The microroughness of the surfaces was measured. We also used the AFM for probing the thickness of the plasma-modified layers. The results correlate with the presence of deuterium measured by NRA depth-profiling. Moreover, the AFM reveals the co-deposited layers formed on surfaces facing the tokamak plasma. The appearance of these layers is clearly correlated to the amount of co-deposited atoms.
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| 2. |
- Almqvist, Nils, et al.
(författare)
-
Imaging human erythrocyte spectrin with atomic force microscopy
- 1994
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Ingår i: Micron. - : Elsevier BV. - 0968-4328 .- 1878-4291. ; 25:3, s. 227-232
-
Tidskriftsartikel (refereegranskat)abstract
- Isolated spectrin covalently attached to a surface in a liquid environment as well as dried on mica has been studied with a contact-mode atomic force microscope. Both pyramidal and conical-type cantilever tip facets were used in the AFM. Our images show structures and give dimensions that correlate well with previous structural studies using transmission electron microscopy.
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| 3. |
- Almqvist, Nils, et al.
(författare)
-
Roughness determination of plasma-modified surface layers with atomic force microscopy
- 1995
-
Ingår i: Thin Solid Films. - 0040-6090 .- 1879-2731. ; 270:1-2, s. 426-430
-
Tidskriftsartikel (refereegranskat)abstract
- Graphite surfaces exposed to the deuterium plasma in the TEXTOR tokamak were characterized in detail by means of scanning probe microscopy, ion beam analysis and colorimetry methods. The aim is to study the composition and structure of thin layer deposits formed on surfaces subjected to the tokamak plasma. The surface roughness was measured and parametrized in terms of fractal dimension and scaling constant. Several different methods for the fractal analysis of plasma-exposed surfaces have been critically evaluated. The main emphasis of this paper is on the correlation between surface roughness (fractal parameters), the amount of deposited atoms and the layer thickness.
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| 4. |
- Almqvist, Nils, et al.
(författare)
-
Scanning probe microscopy and thermo-mechanical characterization of silicon carbide composites
- 1995
-
Ingår i: Fourth Euro-Ceramics. - : Gruppo Ed. Faenza Ed.. - 8881380072 ; , s. 361-368
-
Konferensbidrag (refereegranskat)abstract
- series of SiC-based composites was obtained by sintering. Since such materials are considered for fusion applications, their thermal shock resistance and behaviour under deuterium irradiation are of primary interest. Extensive bulk and surface characterisation of pure and doped (AlN, TiB2, graphite) silicon carbides treated by a deuterium plasma was carried out. The change in surface structure following irradiation is addressed, and major factors influencing deuterium retention are discussed.
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| 5. |
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| 6. |
- Anoushirvani, B., et al.
(författare)
-
Gamma-ray bursts from primordial quark objects in space
- 1997
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Ingår i: Proceedings of the Joint Meeting of the Networks 'The Fundamental Structure of Matter' and 'Tests of the Electroweak Symmetry Breaking', Ouranoupolis, Greece, May 1997.
-
Konferensbidrag (refereegranskat)abstract
- We investigate the possibility that gamma-ray bursts originate in a concentric spherical shell with a given average redshift and find that this is indeed compatible with the data from the third BATSE (3B) catalog. It is also shown that there is enough freedom in the choice of unknown burst properties to allow even for extremely large distances to the majority of bursts. Therefore, we speculate about an early, and very energetic, origin of bursts, and suggest that they come from phase transitions in massive objects of pure quark matter, left over from the Big Bang.
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| 7. |
- Anselmino, Mauro, et al.
(författare)
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Diquarks
- 1993
-
Ingår i: Reviews of Modern Physics. - 0034-6861 .- 1539-0756. ; 65:4, s. 1199-1233
-
Tidskriftsartikel (refereegranskat)abstract
- It is becoming increasingly clear that the concept of a diquark (a two-quark system) is important for understanding hadron structure and high-energy particle reactions. According to our present knowledge of quantum chromodynamics (QCD), diquark correlations arise in part from spin-dependent interactions between two quarks, from quark radial or orbital excitations, and from quark mass differences. Diquark substructures affect the static properties of baryons and the mechanisms of baryon decay. Diquarks also play a role in hadron production in hadron-initiated reactions, deep-inelastic lepton scattering by hadrons, and in e+e- reactions. Diquarks are important in the formation and properties of baryonium and mesonlike semistable states. Many spin effects observed in high-energy exclusive reactions pose severe problems for the pure quark picture of baryons and might be explained by the introduction of diquarks as hadronic constituents. There is considerable controversy, not about the existence of diquarks in hadrons, but about their properties and their effects. In this work a broad selection of the main ideas about diquarks is reviewed.
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| 8. |
- Bergström, Lars, et al.
(författare)
-
Backward production on nuclei and the tube model
- 1980
-
Ingår i: Physical Review D. Particles and fields. - 0556-2821 .- 1089-4918. ; 21:1, s. 305-307
-
Tidskriftsartikel (refereegranskat)abstract
- It is shown that the recent data from Burke et al. on backward production in 200-GeV/c nA collisions are in good agreement with expectations from the collective tube model with tube fragmentation taken into account.
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| 9. |
- Bergström, Lars, et al.
(författare)
-
Estimates of recoil nucleon spectra in high-energy hadron-nucleus collisions
- 1977
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 68:2, s. 177-179
-
Tidskriftsartikel (refereegranskat)abstract
- It is shown that recent data on the recoil nucleon spectrum in 10.5 GeV/c pion-neon collisions are in excellent agreement with a parameter free estimate from the so called tube model for high-energy hadron-nucleus collisions. A simple independent collision model is also treated.
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| 10. |
- Bergström, Lars, et al.
(författare)
-
Is the recently published counterproof of the tube model credible?
- 1978
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 78:2-3, s. 337-341
-
Tidskriftsartikel (refereegranskat)abstract
- It is shown that recent data from pion and proton collision with emulsion nuclei at 200 GeV/c are in perfect agreement with expectations from the collective tube model. The opposite conclusion in publications by Azimov et al. came about because the authors ignored the important effects of target fragmentation.
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| 11. |
- Bergström, Lars, et al.
(författare)
-
The deuteron in high-energy physics
- 1980
-
Ingår i: Reviews of Modern Physics. - 0034-6861 .- 1539-0756. ; 52:4, s. 675-697
-
Tidskriftsartikel (refereegranskat)abstract
- The deuterium nucleus plays an important role in several branches of high-energy physics. We review its present status as a neutron source, a relativistic bound state, a collective six-quark state and a double scatterer.
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| 12. |
- Blaschke, David, et al.
(författare)
-
Diquark condensation effects on hot quark star configurations
- 2004
-
Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 736:1-2, s. 203-219
-
Tidskriftsartikel (refereegranskat)abstract
- The equation of state for quark matter is derived for a nonlocal, chiral quark model within the mean field approximation. We investigate the effects of a variation of the formfactors of the interaction on the phase diagram of quark matter. Special emphasis is on the occurrence of a diquark condensate which signals a phase transition to color superconductivity and its effects on the equation of state under the condition of β-equilibrium and charge neutrality. We calculate the quark star configurations by solving the Tolman-Oppenheimer-Volkoff equations and obtain for the transition from a hot, normal quark matter core of a protoneutron star to a cool diquark condensed one a release of binding energy of the order of ΔMc2˜1053 erg. We find that this energy could not serve as an engine for explosive phenomena since the phase transition is not first order. Contrary to naive expectations the mass defect increases when for a given temperature we neglect the possibility of diquark condensation.
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| 13. |
- Blaschke, David, et al.
(författare)
-
Diquark properties and the TOV equations
- 2001
-
Ingår i: Proceedings of the Conference on Compact Stars in the QCD Phase Diagram (CSQCD), Copenhagen, Denmark, August 15 - 18, 2001. ; , s. 167-173
-
Konferensbidrag (refereegranskat)abstract
- We present various results from including diquark properties and the gap equations into the TOV equations for compact quark objects. One such property is the diquark form factor, which has a strong influence on various quantities. We discuss the consequences for quark stars.
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| 14. |
- Blaschke, D., et al.
(författare)
-
The Phase diagram of three-flavor quark matter under compact star constraints
- 2005
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 72:6
-
Tidskriftsartikel (refereegranskat)abstract
- The phase diagram of three-flavor quark matter under compact star constraints is investigated within a Nambu-Jona-Lasinio model. Global color and electric charge neutrality is imposed for beta-equilibrated superconducting quark matter. The constituent quark masses and the diquark condensates are determined self-consistently in the plane of temperature and quark chemical potential. Both strong and intermediate diquark coupling strengths are considered. We show that in both cases, gapless superconducting phases do not occur at temperatures relevant for compact star evolution, i.e., below T~50 MeV. The stability and structure of isothermal quark star configurations are evaluated. For intermediate coupling, quark stars are composed of a mixed phase of normal (NQ) and two-flavor superconducting (2SC) quark matter up to a maximum mass of 1.21 M[sun]. At higher central densities, a phase transition to the three-flavor color flavor locked (CFL) phase occurs and the configurations become unstable. For the strong diquark coupling we find stable stars in the 2SC phase, with masses up to 1.33 M[sun]. A second family of more compact configurations (twins) with a CFL quark matter core and a 2SC shell is also found to be stable. The twins have masses in the range 1.30...1.33 M[sun]. We consider also hot isothermal configurations at temperature T=40 MeV. When the hot maximum mass configuration cools down, due to emission of photons and neutrinos, a mass defect of 0.1 M[sun] occurs and two final state configurations are possible
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| 15. |
- Carlsson, Ella, et al.
(författare)
-
FIELD STUDIES OF GULLIES AND PINGOS ON SVALBARD – A MARTIAN ANALOG.
- 2008
-
Ingår i: European Planetary Science Congress, 21-26 September 2008. ; 3
-
Konferensbidrag (refereegranskat)abstract
- The gully systems on Mars have been found to superpose young geological surfaces such as dunes and thermal contraction polygons. This in combination with the general absence of superimposed impact craters suggest that the gullies are relatively recent geological formations. The observed gullies display a wide set of morphologies ranging from features seemingly formed by fluvial erosion to others pointing to dry landslide processes. A recent discovery suggests that this is an ongoing process, which appears to occur even today. Several formation mechanisms have been proposed for the Martian gullies, such as liquid carbon dioxide reservoirs, shallow liquid water aquifer, melting ground ice, dry landslide, snow melt and deep liquid water aquifer. However, none of these models can alone explain all the gullies discovered on Mars. So far Martian gullies have been studied only from orbit via remote sensing data. Hydrostatic pingos are perennial ice-cored mounds that may reach an elongated or circular radius of approximately 150 m. They are found in periglacial environments where they are formed by freezing processes in the continuous permafrost. The pingos go through different evolutionary stages as they mature, where the final stage leaves an annular rim left by the collapse of the summit. Images from the High Resolution Imaging Science Experiment (HiRISE) show small fractured mounds in the Martian mid-latitudes. Even though some differences are observed, the best terrestrial analogues for the observed mound morphology are pingos. Gullies and pingos found in Arctic climates on Earth could be an analog for the Martian ones. A comparative analysis might help to understand the formation mechanisms of the Martian pingos and gullies and their possible eroding agent.
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| 16. |
|
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| 17. |
- Dugne, Jean-Jacques, et al.
(författare)
-
Higgs pain? Take a preon!
- 1997
-
Ingår i: Proceedings of the Meeting on 'The Fundamental Structure of Matter' and 'Tests of the Electroweak Symmetry Breaking', Ouranoupolis, Greece, May 1997.
-
Konferensbidrag (refereegranskat)abstract
- The Higgs mechanism is the favourite cure for the main problem with electroweak unification, namely how to reconcile a gauge theory with the need for massive gauge bosons. This problem does not exist in preon models for quark and lepton substructure with composite $Z^0$ and $W$s, which, consequently, also avoid all other theoretical complications and paradoxes with the Higgs mechanism. We present a new, minimal preon model, which explains the family structure, and predicts several new, heavy quarks, leptons and vector bosons. Our preons obey a phenomenological supersymmetry, but without so-called squarks and sleptons, since this SUSY is effective only on the composite scale.
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| 18. |
- Dugne, Jean-Jacques, et al.
(författare)
-
Preon Trinity : a new model of leptons and quarks
- 1999
-
Ingår i: Beyond the desert 1999. - Berlin : Encyclopedia of Global Archaeology/Springer Verlag.
-
Konferensbidrag (refereegranskat)abstract
- A new model for the substructure of quarks, leptons and weak gauge bosons, is discussed. It is based on three fundamental and absolutely stable spin-1/2 preons. Its preon flavour SU(3) symmetry leads to a prediction of nine quarks, nine leptons and nine heavy vector bosons. One of the quarks has charge $-4e/3$, and is speculated to be the top quark (whose charge has not been measured). The flavour symmetry leads to three conserved lepton numbers in all known weak processes, except for some neutrinos, which might either oscillate or decay. There is also a (Cabibbo) mixing of the $d$ and $s$ quarks due to an internal preon-antipreon annihilation channel. An identical channel exists inside the composite $Z^0$, leading to a relation between the Cabibbo and Weinberg mixing angles.
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| 19. |
- Dugne, Jena-Jacques, et al.
(författare)
-
Preon trinity
- 1998
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- We present a new minimal model for the substructure of all known quarks, leptons and weak gauge bosons, based on only three fundamental and stable spin-1/2 preons. As a consequence, we predict three new quarks, three new leptons, and six new vector bosons. One of the new quarks has charge $-4e/3$. The model explains the apparent conservation of three lepton numbers, as well as the so-called Cabibbo-mixing of the $d$ and $s$ quarks, and predicts electromagnetic decays or oscillations between the neutrinos $\bar{\nu}_{\mu}$ ($\nu_{\mu}$) and $\nu_e$ ($\bar{\nu}_e$). Other neutrino oscillations, as well as rarer quark mixings and CP violation can come about due to a small quantum-mechanical mixing of two of the preons in the quark and lepton wave functions.
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| 20. |
- Dugne, Jean-Jacques, et al.
(författare)
-
Preon trinity : a schematic model of leptons, quarks and heavy vector bosons
- 2002
-
Ingår i: Europhysics letters. - : IOP Publishing. - 0295-5075 .- 1286-4854. ; 60:2, s. 188-194
-
Tidskriftsartikel (refereegranskat)abstract
- Quarks, leptons and heavy vector bosons are suggested to be composed of stable spin- (1/2) preons, existing in three flavours, combined according to simple rules. Straightforward consequences of an SU(3) preon-flavour symmetry are the conservation of three lepton numbers, oscillations and decays between some neutrinos, and the mixing of the d and s quarks, as well as of the vector fields W0 and B0. We find a relation between the Cabibbo and Weinberg mixing angles, and predict new (heavy) leptons, quarks and vector bosons, some of which might be observable at the Fermilab Tevatron and the future CERN LHC. A heavy neutrino might even be visible in existing data from the CERN LEP facility.
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| 21. |
|
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| 22. |
- Ekelin, Svante, et al.
(författare)
-
Baryons from diquarks in e+e- annihilation
- 1983
-
Ingår i: Physical Review D. Particles and fields. - 0556-2821 .- 1089-4918. ; 28:1, s. 257-259
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We find experimental support for the view that diquarks appear only as spin-0 objects. When their production rate in the color field of a quark from e+e- annihilation is described by the appropriate Schwinger formula for scalars, it turns out that they must be substantially lighter than earlier believed in order to explain the baryon yield.
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| 23. |
- Ekelin, Svante, et al.
(författare)
-
Hadron pT correlations in quark jets
- 1986
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 56:22, s. 2428-2428
-
Tidskriftsartikel (refereegranskat)
|
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| 24. |
- Ekelin, Svante, et al.
(författare)
-
Indications of hard diquarks in e+e- annihilation
- 1984
-
Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 30:11, s. 2310-2315
-
Tidskriftsartikel (refereegranskat)abstract
- It is suggested that very small spin-0 diquarks are directly produced in e+e- annihilation and then fragment into leading baryons and other hadrons. The most influential diquark is the charmed diquark (uc), due to its high charge. It gives a sizable contribution to the hadronic R factor and to the two-jet angular distribution in the energy region W=4-8 GeV. At these energies, a careful study of Λ production would provide the best additional test of the model.
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| 25. |
- Ekelin, Svante, et al.
(författare)
-
Large-pT protons from constituent diquark scattering
- 1984
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 149:6, s. 509-513
-
Tidskriftsartikel (refereegranskat)abstract
- Recent data from the CERN ISR on the fractional proton yield in pp collisions are explained within the Stockholm diquark model. Describing the proton as a u(ud)0 system, the observed high magnitude and fall-off pT, θ and √s of the proton yield are natural consequences of constituent diquark elastic scattering. The pT and θ dependence favour a value of around 10 GeV2/c2 for the size parameter in the diquark form factor, corresponding to a diquark rms radius of around 0.2 fm. This is consistent with earlier results of the model applied to deep inelastic lepton-nucleon scattering and e+e- annihilation
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| 26. |
- Elfgren, Erik, et al.
(författare)
-
Mass limits for heavy neutrinos
- 2008
-
Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 479:2, s. 347-353
-
Tidskriftsartikel (refereegranskat)abstract
- Context. Neutrinos heavier than MZ/2 ∼ 45 GeV are not excluded by particle physics data. Stable neutrinos heavier than this might contribute to the cosmic gamma ray background through annihilation in distant galaxies, as well as to the dark matter content of the universe.Aims. We calculate the evolution of the heavy neutrino density in the universe as a function of its mass, MN, and then the subsequent gamma ray spectrum from annihilation of distant N ¯N (from 0 < z < 5).Methods. The evolution of the heavy neutrino density in the universe is calculated numerically. To obtain the enhancement due to structure formation in the universe, we approximate the distribution of N to be proportional to that of dark matter in the GalICS model. The calculated gamma ray spectrum is compared to the measured EGRET data.Results. A conservative exclusion region for the heavy neutrino mass is 100 to 200 GeV, both fromEGRET data and our re-evalutation of the Kamiokande data. The heavy neutrino contribution to dark matter is found to be at most 15%.
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| 27. |
- Enström, Daniel, et al.
(författare)
-
A Quark matter dominated universe
- 1998
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- We present a new scenario for the development of the Universe after the Big Bang, built on the conjecture that a vast majority of the primordial quark matter did not undergo a phase transition to normal nuclear matter, but rather split up into massive quark objects that remained stable. Hence, such primordial quark matter would make up the so-called dark matter. We discuss, mostly in qualitative terms, the consequences for galaxy formation, the origin of normal matter, the occurrence of massive black-holes in galactic centres and the cosmic gamma-ray bursts.
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| 28. |
|
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| 29. |
- Enström, Daniel, et al.
(författare)
-
Luminosities of high-redshift objects in an accelerating universe
- 1999
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The results from the Supernova Cosmology Project indicate a relation between cosmic distance and redshift that corresponds to an accelerating Universe, and, as a consequence, the presence of an energy component with negative pressure. This necessitates a re-evaluation of such astrophysical luminosities that have been derived through conventional redshift analyses of, e.g., gamma-ray bursts and quasars. We have calculated corrected luminosity distances within two scenarios; the standard one with a non-zero cosmological constant, and the more recently proposed ``quintessence'', with a slowly evolving energy-density component. We find luminosity corrections from +30 to -40 per cent for redshifts with $z=0 - 10$. This finding implicates that the SCP data do not, by themselves, require a revision of the current, rather qualitative modeling of gamma-ray bursts and quasar properties.
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| 30. |
- Fredriksson, Sverker, et al.
(författare)
-
A comment on diquark fragmentation
- 1983
-
Ingår i: Physical Review D. Particles and fields. - 0556-2821 .- 1089-4918. ; 28:1, s. 255-256
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We discuss diquark fragmentation and suggest that a spectator uu system in deep-inelastic lepton-nucleon scattering has a larger breakup probability than a ud system. The reason for this is argued to be that half of the leftover ud systems are in bound (ud)0 diquark configurations, while no such bound uu diquarks exist.
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| 31. |
- Fredriksson, Sverker, et al.
(författare)
-
A new diquark model for deep inelastic structure functions
- 1982
-
Ingår i: Zeitschrift für Physik C Particles and Fields. - 0170-9739 .- 1431-5858. ; 14:1, s. 35-39
-
Tidskriftsartikel (refereegranskat)abstract
- The bulk of data from deep inelasticep, eD, μp, μN, νp and νN scattering is fitted with a new diquark model of nucleons. The proton is found to be mostly in au(ud) 0 state, where the (ud)0 diquark has spin and isospin zero. There is hence no trace ofSU(6) symmetry among diquarks in nucleons.
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| 32. |
- Fredriksson, Sverker, et al.
(författare)
-
A new indication of diquarks in baryons
- 1982
-
Ingår i: Zeitschrift für Physik C Particles and Fields. - 0170-9739 .- 1431-5858. ; 14:1, s. 41-46
-
Tidskriftsartikel (refereegranskat)abstract
- In data from 100 GeV/c p d, 200 GeV/cpd and 200 GeV/cπ - d collisions there is evidence that the probability for a double-collisiondecreases slowly with increasing number of hadrons produced in the first projectile-nucleon collision. We argue that the presence of diquarks in baryons is the only plausible explanation of such an effect.
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| 33. |
- Fredriksson, Sverker
(författare)
-
A phenomenological two-component picture of large transverse momentum production
- 1976
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 63:3, s. 321-323
-
Tidskriftsartikel (refereegranskat)abstract
- It is suggested that large-pT hadrons can be classified into two categories with completely different properties according to whether they contain a leading quark or just sea quarks from the initial projectile-target system. From simple quark counting we get relations between hadron ratios at large pT, which are consistent with data.
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| 34. |
- Fredriksson, Sverker, et al.
(författare)
-
A potential diquark in the proton
- 1997
-
Ingår i: Zeitschrift für Physik C Particles and Fields. - : Springer Science and Business Media LLC. - 0170-9739 .- 1431-5858. ; 75:1, s. 107-111
-
Tidskriftsartikel (refereegranskat)abstract
- A non-relativistic, QCD-based, potential quark model for the proton and the neutron inevitably predicts a spin-0 diquark structure with an rms radius of the order of 0.35rfm or smaller. We prove this by solving the (S wave) hamiltonian by De Rújula et al. with variational methods. It is essential to include all quark interactions and to use realistic test wave-functions. The protondelta mass difference, the magnetic moments and the nucleon charge radii can be reproduced only with wave functions that contain a mixture of quark-diquark and three-quark states. Approaches with just a quark-diquark component give incorrect magnetic moments, while those without diquarks lead to a too low proton-delta mass difference.
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| 35. |
- Fredriksson, Sverker
(författare)
-
A (ud)-cious model of the proton
- 1994
-
Ingår i: Workshop on diquarks II. - Singapore : World Scientific and Engineering Academy and Society. - 9810216769 ; , s. 14-23
-
Konferensbidrag (refereegranskat)
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| 36. |
|
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| 37. |
- Fredriksson, Sverker, et al.
(författare)
-
Are "Gluon Effects" caused by diquarks?
- 1983
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 51:24, s. 2179-2182
-
Tidskriftsartikel (refereegranskat)abstract
- The possible importance of diquarks in high-energy physics is discussed and it is suggested that this nonperturbative phenomenon can explain the trends in high-energy data that are usually attributed to gluon processes as described by perturbative QCD. Several experimental tests are suggested for discriminating between gluon and diquark phenomena.
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| 38. |
- Fredriksson, Sverker
(författare)
-
Clusters and tubes in multiparticle production from nuclear targets
- 1980
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 45:17, s. 1371-1374
-
Tidskriftsartikel (refereegranskat)abstract
- Recent data on backward pion production in 0.8-4.89-GeV proton-nucleus collisions are analyzed within the scope of models where target nucleons react collectively. It is shown that the nuclear-size dependence in data is a sensitive probe of the effective target mass. The experimental results hint at a synthesis of the cluster ("fluctuon") model and the collective tube model.
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| 39. |
- Fredriksson, Sverker
(författare)
-
Cosmic diquarks
- 1998
-
Ingår i: Workshop on Diquarks III. - Singapore : World Scientific Publishing Co Pte Ltd. - 9810236352 ; , s. 99-108
-
Konferensbidrag (refereegranskat)
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| 40. |
|
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| 41. |
- Fredriksson, Sverker, et al.
(författare)
-
Demon deuterons
- 1981
-
Ingår i: Berkeley 1981, Proceedings, High Energy Heavy Ion Study. ; , s. 423-237
-
Konferensbidrag (refereegranskat)
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| 42. |
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| 43. |
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| 44. |
- Fredriksson, Sverker
(författare)
-
Demons at Celcius?
- 1983
-
Ingår i: Uppsala Workshop. - : Kungl. Tekniska Högskolan.
-
Konferensbidrag (refereegranskat)
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| 45. |
- Fredriksson, Sverker
(författare)
-
Diquarks
- 1987
-
Ingår i: Proceedings. - : Joint Institute for Nuclear Research.
-
Konferensbidrag (refereegranskat)
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|
| 46. |
- Fredriksson, Sverker
(författare)
-
Diquarks
- 1983
-
Ingår i: Proceedings. - : Warsaw Univ., Inst. Theor. Phys..
-
Konferensbidrag (refereegranskat)
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| 47. |
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| 48. |
- Fredriksson, Sverker
(författare)
-
Hello diquark, goodbye gluon !
- 1984
-
Ingår i: New Particle Production. - : Editions Frontieres. ; , s. 479-
-
Konferensbidrag (refereegranskat)
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|
| 49. |
|
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| 50. |
- Fredriksson, Sverker, et al.
(författare)
-
Is dark matter made up of massive quark objects?
- 1999
-
Ingår i: Dark matter in astrophysics and particle physics 1998. - Bristol : IOP Publishing Ltd. - 0750306343 ; , s. 651-658
-
Konferensbidrag (refereegranskat)abstract
- We suggest that dark matter is made up of massive quark objects that have survived from the Big Bang, representing the ground state of "baryonic'' matter. Hence, there was no overall phase transition of the original quark matter, but only a split-up into smaller objects. We speculate that normal hadronic matter comes about through enforced phase transitions when such objects merge or collide, which also gives rise to the cosmic gamma-ray bursts.
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