Abstract Direct photons play an important role as electromagnetic probes from the quark-gluon plasma (QGP) which occurs during ultrarelativistic heavy-ion collisions. In this context, it is of particular interest how the finite lifetime of the QGP affects the resulting photon production. Earlier investigations on this question were accompanied by a divergent contribution from the vacuum polariz...

In heavy ion synchrotrons like SIS 18 high energetic ions can impact on the beam pipe and release gas molecules. This so called ”ion induced desorption” deteriorates the accelerator vacuum and, as a consequence, the beam life time and luminosity. Desorption yields η (released gas atoms or molecules per incident ion) of various materials have been studied at GSI since 2003. A scaling of the deso...

A bstract Flat-space holography requires a thorough understanding of BMS symmetry. We introduce an oscillator construction the highest-weight representation $$ {\mathfrak{bms}}_3 bms3 algebra and show that it is consistent with known results concerning module. take advantag...

The problem of anomalous heat production by hydrogenated metals is analysed in the light of deep sub-barrier nucleon transfer reactions. Consideration of the phenomena of condensed matter low energy nuclear reactions and in-vacuum few-body nuclear transfer reactions suggests that LENRs could be due to interactions among the isotopes of hydrogen and certain metals. It is postulated that hydrogen...

5 We demonstrate how commodity producers can take strategic specula6 tive positions in derivatives markets to soften competition in the spot mar7 ket. In our game, suppliers first choose a portfolio of call options and then 8 compete in supply functions. In equilibrium firms sell forward contracts 9 and buy call options to commit to downward sloping supply functions. Al10 though this strategy i...

This paper reviews techniques for assessing how joint clearances affect the precision of multiloop, multifreedom linkages. Slop, or backlash, arises from the small movements as joint clearances are taken up and, as these movements are generally uncontrolled, the precise location of bodies in the linkage becomes uncertain. This is particularly important when such linkages are used as robot manip...

Theoretical predictions for Bhabha scattering at the two-loop level require the inclusion of hadronic vacuum polarization in the photon propagator. We present predictions for the contributions from reducible amplitudes which are proportional to the vacuum polarization π(q) and from irreducible ones where the vacum polarization appears in a loop representing vertex or box diagramms. The second c...

The Cornell potential with the best fitted parameters αs and κ are modified by adding terms derived from non-perturbative QCD, which are characterized by a series of non-vanishing vacuum condensates of quarks and gluons. In terms of this potential, we study the system of heavy quarkonia. The results show that the correction caused by the additional terms reduces the deviation between the data a...

We discuss the coupling of heavy moduli fields to light fields when the dynamics of the latter, absent such couplings, yields metastable vacua. We show that the survival of the vacuum structure of the local model depends nontrivially on the cross-couplings of the two sectors. In particular we find that for ”local” models (such as those realized by D-branes in type II string theories) with metas...