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Nach einer Eigenzeit des Ästhetischen zu fragen, heißt, sich auf das Problem einzulassen, was für eine Zeit und welche Zeiterfahrung in der Eigenzeit eines Kunstwerks eine besondere Geltung beanspruchen. Die Möglichkeit, dieser Frage nachzugehen, setzt voraus, dass die in der ästhetischen Form verankerten und im Kunstwerk auf Erfahrung drängenden Spannungen einer künstlerischen Eigenzeit auf jeweils begründbare Weise so verstanden werden können, dass sie sich von anderen Formen der Zeit und Zeiterfahrung in bedeutsamer Hinsicht unterscheiden. Ist diese begriffliche Voraussetzung grundsätzlich erfüllt, dann kann von der ästhetischen Eigenzeit als einer Praxis der Zeitgestaltung ausgegangen werden, die bestimmte Modelle und Konstellationen des Zeitlichen auf eine der Kunst eigenen Weise dem Bereich des prinzipiell Erfahrbaren und auf idiomatisch-bestimmte Weise Erkennbaren einschreibt.
A measurement of the transverse momentum spectra of jets in Pb-Pb collisions at sNN−−−√=2.76 TeV is reported. Jets are reconstructed from charged particles using the anti-kT jet algorithm with jet resolution parameters R of 0.2 and 0.3 in pseudo-rapidity |η|<0.5. The transverse momentum pT of charged particles is measured down to 0.15 GeV/c which gives access to the low pT fragments of the jet. Jets found in heavy-ion collisions are corrected event-by-event for average background density and on an inclusive basis (via unfolding) for residual background fluctuations and detector effects. A strong suppression of jet production in central events with respect to peripheral events is observed. The suppression is found to be similar to the suppression of charged hadrons, which suggests that substantial energy is radiated at angles larger than the jet resolution parameter R=0.3 considered in the analysis. The fragmentation bias introduced by selecting jets with a high pT leading particle, which rejects jets with a soft fragmentation pattern, has a similar effect on the jet yield for central and peripheral events. The ratio of jet spectra with R=0.2 and R=0.3 is found to be similar in Pb-Pb and simulated PYTHIA pp events, indicating no strong broadening of the radial jet structure in the reconstructed jets with R<0.3.
[Es] sollen hier einige wenige repräsentative Momente der Konstellation von Erinnerung und Bildlichkeit in das Blickfeld gerückt werden. In diesem Zurückrufen einiger Motive, das ein Offenes bleiben muß, sollen sich wesentliche Züge der Beziehung von Erinnerung und Bild bei Heidegger herauskristallieren, um diese Begriffe in seinem Denken in einem etwas weniger rätselhaften Lichte erscheinen zu lassen. Unter dem Gesichtspunkt dieser Beziehung läßt sich möglicherweise auch Heideggers ebenso grundsätzliche wie apodiktische Behauptung nachvollziehen, "vielleicht ist 'das Denken' stets 'Andenken'". So ließe sich für sie im Sinne einer Heideggerschen Erörterung unvorgreiflich ein Ort finden.
Two-particle angular correlations between unidentified charged trigger and associated particles are measured by the ALICE detector in p–Pb collisions at a nucleon–nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum range 0.7 < pT,assoc < pT,trig < 5.0 GeV/c is examined, to include correlations induced by jets originating from low momentum-transfer scatterings (minijets). The correlations expressed as associated yield per trigger particle are obtained in the pseudorapidity range |η| < 0.9. The near-side long-range pseudorapidity correlations observed in high-multiplicity p–Pb collisions are subtracted from both near-side short-range and away-side correlations in order to remove the non-jet-like components. The yields in the jet-like peaks are found to be invariant with event multiplicity with the exception of events with low multiplicity. This invariance is consistent with the particles being produced via the incoherent fragmentation of multiple parton–parton scatterings, while the yield related to the previously observed ridge structures is not jet-related. The number of uncorrelated sources of particle production is found to increase linearly with multiplicity, suggesting no saturation of the number of multi-parton interactions even in the highest multiplicity p–Pb collisions. Further, the number scales only in the intermediate multiplicity region with the number of binary nucleon–nucleon collisions estimated with a Glauber Monte-Carlo simulation.
We have studied one-proton-removal reactions of about 500MeV/u 17Ne beams on a carbon target at the R3B/LAND setup at GSI by detecting beam-like 15O-p and determining their relative-energy distribution. We exclusively selected the removal of a 17Ne halo proton, and the Glauber-model analysis of the 16F momentum distribution resulted in an s2 contribution in the 17Ne ground state of about 40%.
Beim Nachdenken über die Logik des Nachs im modernen Diskurs drängen sich [...] eine Reihe offener Fragen auf, die uns gegebenenfalls in die Lage versetzen, das Nachdenken über das Nach als eine Art von Nach-Denken aufzufassen. Um zu diesem Bindestrich zu gelangen, könnte zunächst gefragt werden, was es wohl bedeuten möge, wenn es heißt, daß etwas einem anderen "folge". Was hieße es demnach, einem Nach nachzudenken? Markiert das Folgende einen klaren Bruch mit dem Vorausgegangenen, oder schreibt es vielmehr das ihm Vorausgehende in gewisser Weise fort, weil es unausweichlich den Begriffen und Bedingungen dessen verhaftet bleibt, von dem es geglaubt hatte, Abschied genommen zu haben? Ja, ist nicht gerade die Abkehr und das auf sie Folgende eine Art und Weise, nachträglich eben jenes zu stärken und gar zu konnstruieren, desen Verabschiedung die Bewegung des Folgen ja erst ins Leben gerufen hatte?
New experimental data for dissociation of relativistic 17Ne projectiles incident on targets of lead, carbon, and polyethylene targets at GSI are presented. Special attention is paid to the excitation and decay of narrow resonant states in 17Ne. Distributions of internal energy in the three-body system have been determined together with angular and partial-energy correlations between the decay products in different energy regions. The analysis was done using existing experimental data on 17Ne and its mirror nucleus 17N. The isobaric multiplet mass equation is used for assignment of observed resonances and their spins and parities. A combination of data from the heavy and light targets yielded cross sections and transition probabilities for the Coulomb excitations of the narrow resonant states. The resulting transition probabilities provide information relevant for a better understanding of the 17Ne structure.
Experimental study of the ¹⁵O(2p,γ)¹⁷Ne cross section by Coulomb dissociation for the rp process
(2016)
The time-reversed reaction 15O(2p, γ)17Ne has been studied by the Coulomb dissociation technique. Secondary 17Ne ion beams at 500 AMeV have been produced by fragmentation reactions of 20Ne in a beryllium production target and dissociated on a secondary Pb target. The incoming beam and the reaction products have been identified with the kinematically complete LAND-R3B experimental setup at GSI. The excitation energy prior to decay has been reconstructed by using the invariant-mass method. The preliminary differential and integral Coulomb Dissociation cross sections (σCoul) have been calculated, which provide a photoabsorption (σphoto) and a radiative capture cross section (σcap). Additionally, important information about the nuclear structure of the 17Ne nucleus will be obtained. The analysis is in progress.
Freeze-out radii extracted from three-pion cumulants in pp, p–Pb and Pb–Pb collisions at the LHC
(2014)
In high-energy collisions, the spatio-temporal size of the particle production region can be measured using the Bose–Einstein correlations of identical bosons at low relative momentum. The source radii are typically extracted using two-pion correlations, and characterize the system at the last stage of interaction, called kinetic freeze-out. In low-multiplicity collisions, unlike in high-multiplicity collisions, two-pion correlations are substantially altered by background correlations, e.g. mini-jets. Such correlations can be suppressed using three-pion cumulant correlations. We present the first measurements of the size of the system at freeze-out extracted from three-pion cumulant correlations in pp, p–Pb and Pb–Pb collisions at the LHC with ALICE. At similar multiplicity, the invariant radii extracted in p–Pb collisions are found to be 5–15% larger than those in pp, while those in Pb–Pb are 35–55% larger than those in p–Pb. Our measurements disfavor models which incorporate substantially stronger collective expansion in p–Pb as compared to pp collisions at similar multiplicity.
The proton drip-line nucleus 17Ne is investigated experimentally in order to determine its two-proton halo character. A fully exclusive measurement of the 17Ne(p, 2p)16F∗ →15O+p quasi-free one-proton knockout reaction has been performed at GSI at around 500 MeV/nucleon beam energy. All particles resulting from the scattering process have been detected. The relevant reconstructed quantities are the angles of the two protons scattered in quasi-elastic kinematics, the decay of 16F into 15O (including γ decays from excited states) and a proton, as well as the 15O+p relative-energy spectrum and the 16F momentum distributions. The latter two quantities allow an independent and consistent determination of the fractions of l = 0 and l = 2 motion of the valence protons in 17Ne. With a resulting relatively small l = 0 component of only around 35(3)%, it is concluded that 17Ne exhibits a rather modest halo character only. The quantitative agreement of the two values deduced from the energy spectrum and the momentum distributions supports the theoretical treatment of the calculation of momentum distributions after quasi-free knockout reactions at high energies by taking into account distortions based on the Glauber theory. Moreover, the experimental data allow the separation of valence-proton knockout and knockout from the 15O core. The latter process contributes with 11.8(3.1) mb around 40% to the total proton-knockout cross section of 30.3(2.3) mb, which explains previously reported contradicting conclusions derived from inclusive cross sections.