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Numrering	Referens	Omslagsbild	Hitta
1.	Aaboud, M, et al. (författare) ATLAS Collaboration 2017 Ingår i: Nuclear Physics A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 967, s. 942-964 Tidskriftsartikel (refereegranskat)
2.	Aad, G., et al. (författare) ATLAS Collaboration 2014 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 932, s. 572-594 Tidskriftsartikel (refereegranskat)
3.	Abulaiti, Yiming, et al. (författare) Measurement of jet fragmentation in 5.02 TeV proton-lead and proton-proton collisions with the ATLAS detector 2018 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 978, s. 65-106 Tidskriftsartikel (refereegranskat)abstract A measurement of the fragmentation functions of jets into charged particles in p Pb collisions and pp collisions is presented. The analysis utilizes 28 nb(-1) of p Pb data and 26 pb(-1) of pp data, both at root(TN)-T-s= 5.02 TeV, collected in 2013 and 2015, respectively, with the ATLAS detector at the LHC. The measurement is reported in the centre-of-mass frame of the nucleon-nucleon system for jets in the rapidity range vertical bar y*vertical bar <1.6 and with transverse momentum 45 < p(T) < 260 GeV. Results are presented both as a function of the charged-particle transverse momentum and as a function of the longitudinal momentum fraction of the particle with respect to the jet. The pp fragmentation functions are compared with results from Monte Carlo event generators and two theoretical models. The ratios of the p +Pb to pp fragmentation functions are found to be consistent with unity.
4.	Adlarson, Patrik, et al. (författare) Search for eta-mesic He-4 in the dd -> (3)Hen pi(0) and dd -> (3)Hep pi(-) reactions with the WASA-at-COSY facility 2017 Ingår i: Nuclear Physics A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 959, s. 102-115 Tidskriftsartikel (refereegranskat)abstract The search for He-4-eta bound states was performed with the WASA-at-COSY facility via the measurement of the excitation function for the dd -> (3)Hen pi(0) and dd -> (3)Hep pi(-) processes. The deuteron beam momentum was varied continuously between 2.127 GeV/c and 2.422 GeV/c, corresponding to the excess energy for the dd -> He-4 eta reaction ranging from Q = 70 MeV to Q = 30 MeV. The luminosity was determined based on the dd -> (3)Hen reaction and the quasi-free proton proton scattering via dd -> ppn(spectator)n(spectator) reactions. The excitation functions, determined independently for the measured reactions, do not reveal a structure which could be interpreted as a narrow mesic nucleus. Therefore, the upper limits of the total cross sections for the bound state production and decay in dd -> (4He-eta)(bound) -> (3)Hen pi(0) and dd -> (He-4-eta)(bound) -> (3)Hep pi(-) processes were determined taking into account the isospin relation between the both of the considered channels. The results of the analysis depend on the assumptions of the N* (1535) momentum distribution in the anticipated mesic-He-4. Assuming, as in the previous works, that this is identical with the distribution of nucleons bound with 20 MeV in He-4, we determined that (for the mesic bound state width in the range from 5 MeV to 50 MeV) the upper limits at 90% confidence level are about 3 nb and about 6 nb for n pi(0) and p pi(-) channels, respectively. However, based on the recent theoretical findings of the N(1535) momentum distribution in the N-He-3 nucleus bound by 3.6 MeV, we find that the WASA-at-COSY detector acceptance decreases and hence the corresponding upper limits are 5 nb and 10 nb for n pi(0) and p pi(-) channels respectively. (C) 2017 Elsevier B.V. All rights reserved.
5.	Bertoli, Gabriele, et al. (författare) Charged-hadron suppression in Pb plus Pb and Xe plus Xe collisions measured with the ATLAS detector 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 571-574 Tidskriftsartikel (refereegranskat)abstract The ATLAS detector at the LHC recorded 0.49 nb(-1) of Pb+Pb collisions and 25 of pp(-1) collisions, both at the center-of-mass energy 5.02 TeV per nucleon pair. Recently, ATLAS also recorded 30 mu b(-1) of Xe+Xe collisions at the center-of-mass energy 5.44 TeV, which provides a new opportunity to study the system-size dependence of the charged-hadron production in heavy-ion collisions. The large acceptance of the ATLAS detector allows to measure the spectra of charged hadrons in a wide range of pseudorapidity and transverse momentum. The nuclear modification factors R-AA are constructed as a ratio of the spectra measured in Pb+Pb or Xe+Xe collisions to that measured in pp collisions. The R-AA obtained in the two systems are presented for different centrality intervals and the results are discussed.
6.	Bertoli, Gabriele, et al. (författare) Electromagnetic processes with quasireal photons in Pb plus Pb collisions : QED, QCD, and the QGP 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 259-262 Tidskriftsartikel (refereegranskat)abstract Electromagnetic processes, both photon-photon and photon-nucleus, are shown to be useful in studying aspects of QED, QCD, and potentially the QGP. Using lead-lead collisions at root s(NN) = 5.02 TeV, the ATLAS detector has performed measurements of exclusive dimuon production, light-by-light scattering (via exclusive diphoton production), and photo-nuclear dijet production. These are all important examples of ultraperipheral collisions, where the nuclei do not interact hadronically. A recent study of the opening angles of dimuons produced in hadronic heavy-ion collisions, after subtracting heavy-flavor backgrounds, demonstrates that the dimuons carry information correlated with the overlap geometry, potentially about the density of charges in the QGP itself.
7.	Bertoli, Gabriele, et al. (författare) Electroweak probes of small and large systems with the ATLAS detector 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 603-606 Tidskriftsartikel (refereegranskat)abstract Measurements of isolated prompt photon and massive electroweak (W and Z) boson production in different collision systems are of great interest to understand the partonic structure of heavy nuclei, and serve as a constraint on the initial state in larger collision systems. These channels are sensitive to a variety of effects such as the modification of the parton densities in nuclei in certain kinematic regions, and the energy loss of partons as they undergo multiple interactions in the nucleus before the hard parton-parton scattering. High-statistics samples of lead-lead and proton-lead collision data at root s(NN)=5.02 TeV and 8.16 TeV, respectively, taken by the ATLAS experiment at the LHC, as well as proton-proton comparison data at analogous collision energies, allow for a detailed study of these phenomena in data and comprehensive comparisons to the predictions of a variety of theoretical approaches. This paper presents the latest ATLAS results in these topics, including updated results on inclusive prompt photon production in proton-lead collisions over a broad kinematic range and high-precision W boson results in lead lead collisions.
8.	Bertoli, Gabriele, et al. (författare) Flow fluctuations in Pb plus Pb collisions at root s(NN)=5.02 TeV with the ATLAS detector 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 323-326 Tidskriftsartikel (refereegranskat)abstract Measurements of four-particle cumulants c(n){4} for n = 1, 2, 3, 4 are presented using 470 mu b(-1) of Pb+Pb collisions at root s(NN) = 5.02 TeV with the ATLAS detector at the LHC. These cumulants provide information on the event-by-event fluctuations of single harmonics p(v(n)). For the first time, a negative c(1){4} is observed. The c(4){4} is found to be negative in central collisions but changes sign around 20-25% centrality. This behavior is consistent with a nonlinear contribution to v(4) that is proportional to v(2)(2). c(2){4} and c(3){4} are calculated using two reference event classes in order to investigate the influence of volume fluctuations. Over most of the centrality range, c(2){4} and c(3){4} are found to be negative, while in the ultra-central collisions, c(2){4} changes sign and becomes positive, suggesting a deviation from Gaussian behavior in the event-by-event fluctuation of v(2). The magnitudes of the sign change are also found to be dependent of the event class definition.
9.	Bertoli, Gabriele, et al. (författare) Highlights from the ATLAS experiment 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 8-14 Tidskriftsartikel (refereegranskat)abstract This report provides an overview of the new results obtained by the ATLAS Collaboration at the LHC, which were presented at the Quark Matter 2018 conference. These measurements were covered in 12 parallel talks, one flash talk and 11 posters. In this document, a discussion of results is grouped into four areas: electromagnetic interactions, jet quenching, quarkonia and heavy-flavour production, and collectivity in small and larger systems. Measurements from the xenon-xenon collisions based on a short run collected in October 2017 are reported for the first time.
10.	Bertoli, Gabriele, et al. (författare) Jet suppression and jet substructure in Pb plus Pb and Xe plus Xe collisions with the ATLAS detector 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 611-614 Tidskriftsartikel (refereegranskat)abstract This short summary presents latest measurements of the nuclear modification factor, R-AA, for R = 0.4 jets in Pb+Pb collisions at root s(NN) = 5.02 TeV with the ATLAS detector at the LHC. The analysis is performed over a large range of transverse momentum, up to p(T) = 1 TeV, and differentially in jet p(T), rapidity, and collision centrality. The jet R-AA is measured also differentially in the jet mass, m, which provides new information on the dependence of the energy loss on the substructure of jets. Latest results by ATLAS on the dijet momentum balance in Xe+Xe collisions at root s(NN) = 5.44 TeV are presented and compared to the same quantity measured in Pb+Pb collisions at root s(NN) = 5.02 TeV. These recent measurements should help us understand mechanisms of parton energy loss and properties of hot and dense matter created in heavy-ion collisions.
11.	Bertoli, Gabriele, et al. (författare) Measurement of angular and momentum distributions of charged particles within and around jets in Pb plus Pb and pp collisions at root s(NN)=5.02 TeV with ATLAS at the LHC 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 177-179 Tidskriftsartikel (refereegranskat)abstract Studies of the fragmentation of jets into charged particles in heavy-ion collisions can help in understanding the mechanism of jet quenching by the hot and dense QCD matter created in such collisions, the quark-gluon plasma. These proceedings present a measurement of the angular distribution of charged particles around the jet axis in root s(NN) = 5.02 TeV Pb+Pb and pp collisions, done using the ATLAS detector at the LHC. The measurement is performed inside jets reconstructed with the anti-k(t) algorithm with radius parameter R = 0.4, and is extended to regions outside the jet cone. Results are presented as a function of Pb+Pb collision centrality, and both jet and charged-particle transverse momenta.
12.	Bertoli, Gabriele, et al. (författare) Measurement of heavy flavor production and azimuthal anisotropy in small and large systems with ATLAS 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 687-690 Tidskriftsartikel (refereegranskat)abstract Heavy-flavor hadron production and collective motion in A+A collisions provide insight into the energy loss mechanism and transport properties of heavy quarks in the QGP. The same measurements in p+A collisions serve as an important baseline for understanding the observations in A+A collisions. For example, detailed studies of heavy-flavor hadron azimuthal anisotropy in p+A collisions may help to address whether the observed long-range ridge correlation arises from hard or semi-hard processes, or if it is the result of mechanisms unrelated to the initial hardness scale. These proceedings summarize heavy-flavor hadron production, via their semi-leptonic decay to muons in 2.76 TeV Pb+Pb and pp collisions, non-prompt J/psi in 5.02 TeV Pb+Pb and pp collisions, and prompt D-0 mesons in 8.16 TeV p+Pb collisions using ATLAS detector at the LHC. Azimuthal anisotropy of heavy-flavor hadrons is studied via their decay muons in 2.76 TeV Pb+Pb and 8.16 TeV p+Pb collisions, and via non-prompt J/psi in 5.02 TeV Pb+Pb collisions. Strong suppression of heavy-flavor hadron production and azimuthal anisotropy are observed in Pb+Pb collisions, while significant azimuthal anisotropy of heavy-flavor muons is observed in p+Pb collisions, without evidence of the modification of their production rates.
13.	Bertoli, Gabriele, et al. (författare) Measurement of the azimuthal anisotropy of charged particles in 5.02 TeV Pb+Pb and 5.44 TeV Xe+Xe collisions with ATLAS 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 391-394 Tidskriftsartikel (refereegranskat)abstract The data collected by the ATLAS experiment during the 2015 Pb+Pb and 2017 Xe+Xe LHC runs offer new opportunities to study charged particle azimuthal anisotropy. The high-statistics Pb+Pb sample allows for a detailed study of the azimuthal anisotropy of produced particles. This should improve the understanding of initial conditions of nuclear collisions, hydrodynamical behavior of quark-gluon plasma and parton energy loss. New ATLAS measurements of differential and global Fourier harmonics of charged particles (v(n)) in 5.02 TeV Pb+Pb and 5.44 TeV Xe+Xe collisions in a wide range of transverse momenta, pseudorapidity (vertical bar eta vertical bar < 2.5) and collision centrality are presented. The higher order harmonics, sensitive to fluctuations in the initial state, are measured up to n = 7 using the two-particle correlation, cumulant and scalar product methods. The dynamic properties of QGP are studied using a recently-proposed modified Pearson's correlation coefficient, rho(v(n)(2), p(T)), between the event-wise mean transverse momentum and the magnitude of the flow vector in 5.02 TeV Pb+Pb and p+Pb collisions. Several important observations are made. The elliptic and triangular flow harmonics show an interesting universal p(T)-scaling. A linear correlation between the v(2) and v(3) coefficients at low and high p(T) ranges is observed and quantified. The correlation coefficient for v(2) is found to be negative in peripheral and positive in central Pb+Pb collisions. The value for v(3) is found to be much smaller than for v(2) and have similar centrality behavior as the v(2).
14.	Bertoli, Gabriele, et al. (författare) Measurement of the flow harmonic correlations in pp, p plus Pb and low multiplicity Pb plus Pb collisions with the ATLAS detector at the LHC 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 479-482 Tidskriftsartikel (refereegranskat)abstract Recent measurements of the correlations between flow harmonics obtained using four-particle symmetric cumulants and three-particle asymmetric cumulants with the ATLAS detector at the LHC are described. The data sets of pp, p+Pb and peripheral Pb+Pb collisions at various energies are analyzed, aiming to probe the long-range collective nature of multi-particle production in small systems. The sensitivity of the standard cumulant method to non-flow correlations is investigated by introducing the subevents method. A systematic reduction of non-flow effects is observed when using the two-subevent method. Further reduction is observed with the three-subevent method that is consistent with the results obtained with the four-subevent one. A negative correlation between v(2) and v(3) and a positive correlation between v(2) and v(4), for all studied collision systems and over full multiplicity range, is observed. The correlation strength computed as symmetric cumulants normalized by the < v(n)(2)> is similar for all collision systems and weakly depends on multiplicity. These measurements provide new evidence for long-range multi-particle collectivity in small collision systems and quantify the nature of its event-by-event fluctuations.
15.	Bertoli, Gabriele, et al. (författare) Photon-tagged measurements of jet quenching with ATLAS 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 595-598 Tidskriftsartikel (refereegranskat)abstract Events containing a high transverse momentum (p(T)) prompt photon offer a useful way to study the dynamics of the hot, dense medium produced in heavy ion collisions. Because photons do not carry color charge, they are unaffected by the medium, and thus provide information about the momentum, direction, and flavor (quark or gluon) of the associated hard-scattered parton before it begins to shower and become quenched. In particular, the presence of a high-p(T) photon can be used to select pp and Pb+Pb events with the same configuration before quenching, limiting the effects of quenching-induced selection biases present in other jet measurements. The large statistics pp and Pb+Pb data delivered by the LHC in 2015 allow for a detailed study of photon-tagged jet quenching effects, such as the overall parton energy loss and modified structure of the component of the shower which remains correlated with the initial parton direction (e.g. in cone). In this proceeding, photon-tagged measurements of jet quenching by ATLAS are reported.
16.	Bugaev, K. A., et al. (författare) Going beyond the second virial coefficient in the hadron resonance gas model 2018 Ingår i: Nuclear Physics A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 970, s. 133-155 Tidskriftsartikel (refereegranskat)abstract We develop a novel formulation of the hadron resonance gas model which, besides a hard-core repulsion, explicitly accounts for the surface tension induced by the interaction between the particles. Such an equation of state allows us to go beyond the Van der Waals approximation for any number of different hard-core radii. A comparison with the Carnahan Starling equation of state shows that the new model is valid for packing fractions 0.2-0.22, while the usual Van der Waals model is inapplicable at packing fractions above 0.1-0.11. Moreover, it is shown that the equation of state with induced surface tension is softer than the one of hard spheres and remains causal at higher particle densities. The great advantage of our model is that there are only two equations to be solved and neither their number nor their form depend on the values of the hard-core radii used for different hadronic resonances. Such an advantage leads to a significant mathematical simplification compared to other versions of truly multi-component hadron resonance gas models. Using this equation of state we obtain a high-quality fit of the ALICE hadron multiplicities measured at the center-of-mass energy 2.76 TeV per nucleon and we find that the dependence of chi(2)/ndf on the temperature has a single global minimum in the traditional hadron resonance gas model with the multi-component hard-core repulsion. Also we find two local minima of chi(2)/ndf in the model in which the proper volume of each hadron is proportional to its mass. However, it is shown that in the latter model a second local minimum located at higher temperatures always appears far above the limit of its applicability. (C) 2017 Elsevier B.V. All rights reserved.
17.	Changizi, Sara A., et al. (författare) Empirical pairing gaps, shell effects, and di-neutron spatial correlation in neutron-rich nuclei 2015 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 940, s. 210-226 Tidskriftsartikel (refereegranskat)abstract The empirical pairing gaps derived from four different odd-even mass staggering formulas are compared. By performing single-j shell and multi-shell seniority model calculations as well as by using the standard HFB approach with Skyrme force we show that the simplest three-point formula δC(3)(N)=12[B(N,Z)+B(N-2,Z)-2B(N-1,Z)] can provide a good measure of the neutron pairing gap in even-N nuclei. It removes to a large extent the contribution from the nuclear mean field as well as contributions from shell structure details. It is also less contaminated by the Wigner effect for nuclei around N=Z. We also show that the strength of δC(3)(N) can serve as a good indication of the two-particle spatial correlation in the nucleus of concern and that the weakening of δC(3)(N) in some neutron-rich nuclei indicates that the di-neutron correlation itself is weak in these nuclei.
18.	Changizi, Sara A., et al. (författare) Odd-even staggering in neutron drip line nuclei 2016 Ingår i: Nuclear Physics A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 951, s. 97-115 Tidskriftsartikel (refereegranskat)abstract We have done systematic Hartree-Fock-Bogoliubov calculations in coordinate space on the one-quasi-particle energies and binding energy odd-even staggering (OES) in semi-magic nuclei with the zero-range volume, mixed and surface pairing forces in order to explore the influence of their density dependence. The odd-N isotopes are calculated within the blocking scheme. The strengths for the pairing forces are determined in two schemes by fitting locally to reproduce pairing gap in 120Sn and globally to all available data on the OES of semi-magic nuclei with Z≥8. In the former calculations, there is a noticeable difference between the neutron mean gaps in neutron-rich O, Ca, Ni and Sn isotopes calculated with the surface pairing and those with the mixed and volume pairing. The difference gets much smaller if the globally optimized pairing strengths are employed. The heavier Pb isotopes show the opposite trend. Moreover, large differences between the mean gap and the OES may be expected in both calculations when one goes towards the neutron drip line.
19.	Dipanwita, Dutta, et al. (författare) Physics program of PÌ„ANDA experiment at FAIR 2011 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 862-€“863:0, s. 231-237 Tidskriftsartikel (refereegranskat)
20.	Dzysiuk, Nataliia, et al. (författare) Cross section measurement of the Tb-159(n, gamma)Tb-160 nuclear reaction 2015 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 936, s. 6-16 Tidskriftsartikel (refereegranskat)abstract The cross section of the Tb-159(n, gamma)Tb-160 reaction was measured in four mono-energetic neutron fields of energy 3.7, 4.3, 5.4, and 6.85 MeV, respectively, with the activation technique applied to metal discs of natural composition. To ensure an acceptable precision of the results all major sources of uncertainties were taken into account. Calculations of detector efficiency, incident neutron spectrum and correction factors were performed with the Monte Carlo code (MCNPX), whereas theoretical excitation functions were calculated with the TALYS-1.2 code and compared to the experimental cross section values. This paper presents both measurements and calculation leading to the cross section values.
21.	Göök, A., et al. (författare) Fragment characteristics from fission of U-238 and U-234 induced by 6.5-9.0 MeV bremsstrahlung 2011 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 851:1, s. 1-16 Tidskriftsartikel (refereegranskat)abstract Fission of U-238 and U-234 induced by bremsstrahlung of 6.5-9.0 MeV endpoint energy has been investigated at the superconducting Darmstadt electron linear accelerator S-DALINAC. Using a twin Frisch grid ionization chamber, fission-fragment energy and mass distributions have been determined by means of the double kinetic-energy technique. Results on the fission-fragment characteristics from U-238(gamma, f) are in agreement with results from the literature. In addition fission-fragment mass and energy distributions from U-234(gamma, f) are presented for the first time in this energy region. An analysis of fission modes within the Brosa model has been performed. The relative yield of the S 1 mode was found to be (13 +/- 3)% in U-234 and (35 +/- 2)% in U-238.
22.	Jia, Jiangyong, et al. (författare) Heavy Ion Results from ATLAS 2017 Ingår i: Nuclear Physics A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 967, s. 51-58 Tidskriftsartikel (refereegranskat)abstract These proceedings provide an overview of the new results obtained with the ATLAS detector at the LHC, which were presented in the Quark Matter 2017 conference. These results were covered by twelve parallel talks, one flash talk and eleven posters. These proceedings group these results into five areas: initial state, jet quenching, quarkonium production, longitudinal flow dynamics, and collectivity in small systems.
23.	Johansson, Håkan T, 1977, et al. (författare) The unbound isotopes He-9,He-10 2010 Ingår i: Nuclear Physics A. - Elsevier : Elsevier BV. - 0375-9474 .- 1873-1554. ; 842:1-4, s. 15-32 Tidskriftsartikel (refereegranskat)abstract The unbound nuclei He-9 and He-10 have been produced in proton-knockout reactions from a 280 MeV/u Li-11 beam impinging on a liquid hydrogen target at the ALADIN-LAND setup at GSI. Information on their nuclear structure has been obtained from the relative-energy spectra, He-8 + n and He-8 + 2n, employing reaction models incorporating the structure of Li-11. The (8H)e + n relative-energy spectrum is dominated by a strong peak-like structure at low energy, which may be interpreted within the effective-range approximation as the result of an s-wave interaction with a neutron scattering length of -3.17(66) fm. This spectrum also shows evidence for resonance states at 1.33(8) MeV and at 2.4 MeV above the He-8 + n threshold. It is argued that the s-state might not be the He-9 ground state. For He-8 + n + n, the analysis of the relative-energy spectrum gives two alternative possibilities for an interpretation: either a narrow resonance at 1.42(10) MeV (Gamma = 1.11(76) MeV) superimposed on a correlated background, or two overlapping resonances, a ground state at 1.54(11) MeV (Gamma = 1.91(41) MeV) together with an excited state at 3.99(26) MeV (Gamma = 1.64(89) MeV). The two possible interpretations are discussed. (C) 2010 Elsevier B.V. All rights reserved.
24.	Johansson, Håkan T, 1977, et al. (författare) Three-body correlations in the decay of He-10 and Li-13 2010 Ingår i: Nuclear Physics A. - Elsevier : Elsevier BV. - 0375-9474 .- 1873-1554. ; 847:1-2, s. 66-88 Tidskriftsartikel (refereegranskat)
25.	Kastanas, Konstatinos A., et al. (författare) Measurements of photo-nuclear jet production in Pb plus Pb collisions with ATLAS 2017 Ingår i: Nuclear Physics A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 967, s. 277-280 Tidskriftsartikel (refereegranskat)abstract Ultra-peripheral heavy ion collisions provide a unique opportunity to study the parton distributions in the colliding nuclei via the measurement of photo-nuclear jet production. An analysis of jet production in ultra-peripheral Pb+Pb collisions at root S-NN = 5.02 TeV performed using data collected with the ATLAS detector in 2015 is described. The data set corresponds to a total Pb+Pb integrated luminosity of 0.38 nb(-1). The ultra-peripheral collisions are selected using a combination of forward neutron and rapidity gap requirements. The cross-sections, not unfolded for detector response, are compared to results from PYTHIA Monte Carlo simulations re-weighted to match a photon spectrum obtained from the STARLIGHT model. Qualitative agreement between data and these simulations is observed over a broad kinematic range suggesting that using these collisions to measure nuclear parton distributions is experimentally realisable.
26.	Moriguchi, T., et al. (författare) Density distribution of 14Be from reaction cross-section measurements 2014 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 929:0, s. 83-93 Tidskriftsartikel (refereegranskat)abstract Abstract We measured the reaction cross sections of the two-neutron halo nucleus 14Be with proton and carbon targets at about 41 and 76 MeV/nucleon. Based on a Glauber model calculation, we deduced the matter density distribution of 14Be in which previously measured interaction cross sections at relativistic energies were also included. An s-wave dominance in 14Be has been confirmed, although the halo tail of 14Be is not distributed as much as that of 11Li. Significant mixing of the p-wave in addition to the s- and d-wave is also suggested.
27.	Perotti, Elisabetta, et al. (författare) Lifetime of the eta ' meson at low temperature 2016 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 950, s. 29-63 Tidskriftsartikel (refereegranskat)abstract This work constitutes one part of an investigation of the low-temperature changes of the properties of the eta ' meson. In turn these properties are strongly tied to the U(1)(A) anomaly of Quantum Chromodynamics. The final aim is to explore the interplay of the chiral anomaly and in-medium effects. We determine the lifetime of an eta ' meson being at rest in a strongly interacting medium as a function of the temperature. To have a formally well-defined low-energy limit we use in a first step Chiral Perturbation Theory for a large number of colors. We determine the pertinent scattering amplitudes in leading and next-to-leading order. In a second step we include resonances that appear in the same mass range as the eta ' meson. The resonances are introduced such that the low-energy limit remains unchanged and that they saturate the corresponding low-energy constants. This requirement fixes all coupling constants. We find that the width of the eta ' meson is significantly increased from about 200 keV in vacuum to about 10 MeV at a temperature of 120 MeV.
28.	Qi, Chong, et al. (författare) Analytic proof of partial conservation of seniority in j=9/2 shells 2012 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 884, s. 21-35 Tidskriftsartikel (refereegranskat)abstract A partial conservation of the seniority quantum number in j = 9/2 shells has been found recently in a numerical application. In this paper an analytic proof for this problem is derived as an extension of the work [L. Zamick, P. Van Isacker, Phys. Rev. C 78 (2008) 044327]. We analyze the properties of the non-diagonal interaction matrix elements with the help of the one-particle and two-particle coefficients of fractional parentage (cfp's). It is found that all non-diagonal (and the relevant diagonal) matrix elements can be re-expressed in simple ways and are proportional to certain one-particle cfp's. This remarkable occurrence of partial dynamic symmetry is the consequence of the peculiar property of the j = 9/2 shell, where all it = 3 and 5 states are uniquely defined.
29.	Singh, B., et al. (författare) Study of doubly strange systems using stored antiprotons 2016 Ingår i: Nuclear Physics A. - : Elsevier. - 0375-9474 .- 1873-1554. ; 954, s. 323-340 Tidskriftsartikel (refereegranskat)abstract Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the PANDA experiment at FAIR. For the first time, high resolution gamma-spectroscopy of doubly strange Lambda Lambda-hypernuclei will be performed, thus complementing measurements of ground state decays of Lambda Lambda-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Xi(-) -atoms will be feasible and even the production of Omega(-) -atoms will be within reach. The latter might open the door to the vertical bar S vertical bar = 3 world in strangeness nuclear physics, by the study of the hadronic Omega(-) -nucleus interaction. For the first time it will be possible to study the behavior of Xi(+) in nuclear systems under well controlled conditions.
30.	Takechi, M., et al. (författare) Measurements of nuclear radii for neutron-rich Ne isotopes 28-32Ne 2010 Ingår i: Nuclear Physics A. - Elsevier : Elsevier BV. - 0375-9474 .- 1873-1554. ; 834:1-4, s. 412c-415c Tidskriftsartikel (refereegranskat)abstract Interaction cross sections (σI) for neutron-rich Ne isotopes, 28-32Ne on C target have been measured at 240A MeV using the RIBF at RIKEN. A large enhancement of σI beyond the systematics of stable nuclei have been observed for neutron-rich Ne isotopes, particularly for 31Ne. The possible halo structure for 29,31Ne which would be caused by the lowering of the pf-shell and nuclear deformation of Ne isotopes are discussed by the preliminary analysis.
31.	Wang, X. B., et al. (författare) Isovector channel of quark-meson-coupling model and its effect on symmetry energy 2011 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 865:1, s. 57-68 Tidskriftsartikel (refereegranskat)abstract The non-relativistic approximation Of the quark-meson-coupling model has been discussed and compared with the Skyrme-Hartree-Fock model which includes spin exchanges. Calculations show that the spin-exchange interaction has important effect on the descriptions of finite nuclei and nuclear matter through the Fock exchange. Also in the quark-meson-coupling model, it is the Fock exchange that leads to a nonlinear density-dependent isovector channel and changes the density-dependent behavior of the symmetry energy.
32.	Xu, Zhenxiang, 1985-, et al. (författare) Analysis of the unbound spectrum of 12Li. 2011 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 850, s. 53-68 Tidskriftsartikel (refereegranskat)abstract The unbound nucleus 12Li is evaluated by studying three-neutron one-proton excitations within the multistepshell model in the complex energy plane. It is found that the ground state of this system consists of anantibound 2− state. A number of narrow states at low energy are found which ensue from the coupling ofresonances in 11Li to continuum states close to threshold.
33.	Xu, Zhen Xiang, et al. (författare) Multistep shell model description of spin-aligned neutron-proton pair coupling 2012 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 877, s. 51-58 Tidskriftsartikel (refereegranskat)abstract The recently proposed spin-aligned neutron-proton pair coupling scheme is studied within a non-orthogonal basis in term of the multistep shell model. This allows us to identify simultaneously the roles played by other configurations such as the normal pairing term. The model is applied to four-, six- and eight-hole N = Z nuclei below the core Sn-100.
34.	Yuan, C. X., et al. (författare) Shell evolution in neutron-rich carbon isotopes : Unexpected enhanced role of neutron-neutron correlation 2012 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 883, s. 25-34 Tidskriftsartikel (refereegranskat)abstract Full shell-model diagonalization has been performed to study the structure of neutron-rich nuclei around C-20. We investigate in detail the roles played by the different monopole components of the effective interaction in the evolution of the N = 14 shell in C, N and O isotopes. It is found that the relevant neutron neutron monopole terms, V-d5/2d5/2(nn) and V-s1/2s1/2(nn) contribute significantly to the reduction of the N = 14 shell gap in C and N isotopes in comparison with that in O isotopes. The origin of this unexpectedly large effect, which is comparable with (sometimes even larger than) that caused by the proton neutron interaction, is related to the enhanced configuration mixing in those nuclei due to many-body correlations. Such a scheme is also supported by the large B(E2) value in the nucleus C-20 which has been measured recently.
35.	Zhou, Mingliang, et al. (författare) Flow fluctuations in Pb plus Pb collisions at √sNN=5.02 TeV with the ATLAS detector 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 982, s. 323-326 Tidskriftsartikel (refereegranskat)abstract Measurements of four-particle cumulants c(n){4} for n = 1, 2, 3, 4 are presented using 470 mu b(-1) of Pb+Pb collisions at root s(NN) = 5.02 TeV with the ATLAS detector at the LHC. These cumulants provide information on the event-by-event fluctuations of single harmonics p(v(n)). For the first time, a negative c(1){4} is observed. The c(4){4} is found to be negative in central collisions but changes sign around 20-25% centrality. This behavior is consistent with a nonlinear contribution to v(4) that is proportional to v(2)(2). c(2){4} and c(3){4} are calculated using two reference event classes in order to investigate the influence of volume fluctuations. Over most of the centrality range, c(2){4} and c(3){4} are found to be negative, while in the ultra-central collisions, c(2){4} changes sign and becomes positive, suggesting a deviation from Gaussian behavior in the event-by-event fluctuation of v(2). The magnitudes of the sign change are also found to be dependent of the event class definition .
36.	Aaboud, M, et al. (författare) ATLAS Collaboration 2019 Ingår i: XXVIIth International Conference on Ultrarelativistic Nucleus–Nucleus Collisions (Quark Matter 2018). - 0375-9474. ; 982, s. 985-1009 Konferensbidrag (refereegranskat)
37.	Acharya, S, et al. (författare) ALICE Collaboration 2019 Ingår i: XXVIIth International Conference on Ultrarelativistic Nucleus–Nucleus Collisions (Quark Matter 2018). - 0375-9474. ; 982, s. 975-984 Konferensbidrag (refereegranskat)
38.	Adam, J., et al. (författare) ALICE Collaboration 2016 Ingår i: Nuclear Physics A. - 0375-9474. ; 956, s. 913-921 Tidskriftsartikel (refereegranskat)
39.	Adare, A, et al. (författare) PHENIX Collaboration 2017 Ingår i: Nuclear Physics A. - 0375-9474. ; 967, s. 996-1003 Tidskriftsartikel (refereegranskat)
40.	Adare, A., et al. (författare) PHENIX Collaboration 2019 Ingår i: XXVIIth International Conference on Ultrarelativistic Nucleus–Nucleus Collisions (Quark Matter 2018). - 0375-9474. ; 982, s. 1053-1059 Konferensbidrag (refereegranskat)
41.	BRYNGEMARK, LENE, et al. (författare) ATLAS Collaboration 2016 Ingår i: Nuclear Physics A. - : Elsevier. - 0375-9474. ; 956, s. 922-944 Tidskriftsartikel (refereegranskat)
42.	Acharya, S, et al. (författare) Production of 4He and He‾4 in Pb–Pb collisions at sNN=2.76TeV at the LHC 2018 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 971, s. 1-20 Tidskriftsartikel (refereegranskat)abstract Results on the production of 4He and He‾4 nuclei in Pb–Pb collisions at sNN=2.76TeV in the rapidity range \|y\|
43.	Aggarwal, M. M., et al. (författare) Photon and eta production in p plus Pb and p plus C collisions at root(NN)-N-S=17.4 GeV 2013 Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474. ; 898, s. 14-23 Tidskriftsartikel (refereegranskat)abstract Measurements of direct photon production in p + Pb and p + C collisions at root(NN)-N-s = 17.4 GeV are presented. Upper limits on the direct photon yield as a function of p(T) are derived and compared to the results for Pb + Pb collisions at root(NN)-N-s = 17.3 GeV. The production of the eta meson, which is an important input to the direct photon signal extraction, has been determined in the eta -> 2 gamma channel for p + C collisions at root(NN)-N-s = 17.4 GeV. (c) 2012 Elsevier B.V. All rights reserved.
44.	Basso, Eduardo, et al. (författare) The Drell-Yan process as a testing ground for parton distributions up to LHC 2016 Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474. ; 948, s. 63-77 Tidskriftsartikel (refereegranskat)abstract The Drell-Yan massive dilepton production in hadron-hadron collisions provides a unique tool, complementary to Deep Inelastic Scattering, for improving our understanding of hadronic substructure and in particular for testing parton distributions. We will consider measurements of the differential and double-differential Drell-Yan cross sections from FNAL Tevatron up to CERN LHC energies and they will be compared to the predictions of perturbative QCD calculations using most recent sets (CT14 and MMHT14) of parton distribution functions, as well as those provided by the statistical approach.
45.	Basso, Eduardo, et al. (författare) The landscape of W± and Z bosons produced in pp collisions up to LHC energies 2017 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 966, s. 113-123 Tidskriftsartikel (refereegranskat)abstract We consider a selection of recent experimental results on electroweak W±,Z gauge boson production in pp collisions at BNL RHIC and CERN LHC energies in comparison to prediction of perturbative QCD calculations based on different sets of NLO parton distribution functions including the statistical PDF model known from fits to the DIS data. We show that the current statistical PDF parametrization (fitted to the DIS data only) underestimates the LHC data on W±,Z gauge boson production cross sections at the NLO by about 20%. This suggests that there is a need to refit the parameters of the statistical PDF including the latest LHC data.
46.	Bierlich, Christian (författare) Microscopic collectivity : The ridge and strangeness enhancement from string–string interactions 2019 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 982, s. 499-502 Tidskriftsartikel (refereegranskat)abstract We present the microscopic model for collective effects, built on string–string interactions (string shoving and rope hadronization), recently implemented in the PYTHIA8 and DIPSY event generators. Rope hadronization is shown to give a good description of strangeness enhancement across pp, pA and AA collision systems, while string shoving qualitatively describes the ridge observed in pp collisions.
47.	Burdeinyi, D., et al. (författare) Cross section asymmetry of two-body carbon disintegration 12C(γ,p)11B with polarized photons at energy 40–50 MeV 2017 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 957, s. 321-331 Tidskriftsartikel (refereegranskat)abstract The cross section asymmetry of C12(γ,p01)B11 and C12(γ,p2−6)B11 reactions has been studied at the energy range 40–55 MeV, using linearly polarized tagged photons of the MAX-lab facility. The asymmetry of the C12(γ,p01)B11 processes, which assume the one-body mechanism of the reaction, is Σ≈0.82±0.05 for photon energies 45–50 MeV. The asymmetry for the C12(γ,p2−6)B11 reactions, which produce a maximum at excitation energy ∼6 MeV, is Σ≈0.53±0.13 for a photon energy 49 MeV. It is close to the asymmetry of reaction of the free deuteron photodisintegration, and can be resulted from the two-body mechanism of the photon absorption.
48.	Christiansen, Peter (författare) High p(T) identified particle production. in ALICE 2013 Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474. ; 910, s. 20-26 Tidskriftsartikel (refereegranskat)abstract The ALICE experiment is a dedicated heavy-ion physics detector at the LHC with unique capabilities for studying identified particle production. In this proceeding preliminary results for R-AA of pi and K+p (sum), are reported, based on measurements in pp at root s = 2.76 TeV and Pb-Pb at root s(NN) = 2.76 TeV. The results are compared to theoretical predictions and measurements at RHIC.
49.	Christiansen, Peter (författare) Identified particle production in p-Pb collisions measured with the ALICE detector 2014 Ingår i: Nuclear Physics, Section A. - : Elsevier BV. - 0375-9474. ; 926, s. 264-269 Tidskriftsartikel (refereegranskat)abstract ALICE has unique capabilities among the LHC experiments for particle identification (PID) at mid-rapidity (vertical bar eta vertical bar < 0.9) over a wide range of transverse momentum (pT). In this proceeding(1) recent measurements of PT spectra for pi, K, K-s(0), p, and Lambda in p-Pb collisions are presented and compared to results from Pb-Pb and pp. In particular the implications for the question of the existence of radial flow in small systems is discussed. (C) 2014 CERN. Published by Elsevier B.V. All rights reserved.
50.	Cortina-Gil, D., et al. (författare) One-neutron knockout of n-rich Ne isotopes at relativistic energies 2010 Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 834:1-4, s. 485C-487C Konferensbidrag (refereegranskat)abstract Longitudinal fragment-momentum distributions resulting front one-neutron knockout of 40 different neutron-rich exotic species (Z ranging from 6-13) have been recently measured at high-energy (700 A MeV) using the FRS at GSI. This paper concentrates on results obtained for the Ne isotopic chain where five isotopes (Ne-24-Ne-28) have been Studied. The comparison of those experimental results with simple model calculations shows the evolution of the nuclear structure across neutron numbers N=14,16 in this transitional region in the neighbourhood of the island of inversion.

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