119417898
Has Nucleonic Matter at the Critical Point Been Produced in Recent Multifragmentation Experiments
For nuclei in five different mass regions the critical temperatures, at which the surface tension vanishes, are derived from information on the liquid branch of the coexistence curve. These critical temperatures increase with increasing mass and, for higher masses are well above recently reported critical temperatures obtained from Fisher Droplet model and percolation model analyses. However, for the lowest mass region nuclei, with 30<A<60, this analysis indicates that nucleonic matter has been produced essentially at the critical point, characterized by Tc and rho_c.
122288526
High pT Physics in the Forward Region
Abstract Two of the most interesting results to emerge from RHIC have been suppression of high p T particles produced at y = 0 in AuAu collisions and a suppression of high p Z particles in d-Au collisions. These have been explained in terms of quark energy loss in the final state and suppression of the initial soft gluon density respectively. In gold-gold collisions one would naively expect the first effect to get weaker and the second stronger with increasing rapidity. Intriguingly the nuclear modification factor shows almost no change with rapdity. We will use several tools to try to understand this result. The theoretical constructs of color glass condensate and quark recombination have been proposed as answers to this problem. The experimental work begins with operational definitions of high p T and forward rapidity and a review of pp collisions. Using a wide range of data on limiting fragmentation, proton/pion ratios and the dependence of R AuAu on energy density we tentatively conclude that the hot partonic matter extends into the forward region and that high p T particles emerge from the surface of this matter.
119203216
Performance of the combined zero degree calorimeter for CMS
The combined zero degree calorimeter (ZDC) is a combination of sampling quartz/tungsten electromagnetic and hadronic calorimeters. Two identical combined calorimeters are located in the LHC tunnel at CERN at the straight section ~140 m on each side of the CMS interaction vertex and between the two beam pipes. They will detect very forward |?| ? 8.5 photons and neutrons. ZDC information can be used for a variety of physics measurements as well as improving the collision centrality determination in heavy-ion collisions. Results are presented for ZDC performance studies with the CERN SPS H2 test beam.
118726538
Detecting Elastic pp Scattering by Radiative Photons in CMS at the LHC
Photon bremsstrahlung is studied for identifying elastic proton-proton interactions in the CMS experiment at the LHC. In addition to measurement of the elastic pp cross section (assuming that the elastic slope is known) the bremsstrahlung photons will allow evaluation of the total pp cross section, luminosity and alignment of the Zero Degree Calorimeters (ZDCs).
117724729
Particle spectra and interferometry results from NA44
16904212
Caloric curves and critical behavior in nuclei
Data from a number of different experimental measurements are used to construct caloric curves for five different regions of nuclear mass. These curves are qualitatively similar, and exhibit plateaus at the higher excitation energies. The limiting temperatures represented by the plateaus decrease with increasing nuclear mass, and are in very good agreement with results of recent calculations employing either a chiral symmetry model or the Gogny interaction. This agreement strongly favors a soft equation of state. Evidence is presented which suggests that critical excitation energies and critical temperatures might be determined from caloric curve measurements when the mass variations inherent in such measurements are taken into account.
119217305
Overview of Deeply Virtual Compton Scattering at HERMES
Deeply Virtual Compton Scattering represents the best experimental channel through which to understand Generalised Parton Distributions. The HERMES experiment measured the most diverse set of DVCS results of any experiment; this talk discusses the most recent sets of DVCS results released by HERMES and the unique experimental conditions found at HERMES that facilitated the measurements. We also examine the various ways in which the HERMES experimental measurements are being used to constrain GPDs and how future experiments can learn from the HERMES program.
120484753
The front-end readout electronics for the P̄ANDA Focussing-Lightguide Disc DIRC
One of the key detectors of the upcoming ANDA experiment for particle identification will be the Focussing-Lightguide Disc DIRC, based on a novel detector technique. It will use a fused silica disc as a solid radiator to generate Cherenkov light by the passing of charged particles. These photons will be transported by total-internal-reflection to the rim, where LiF crystals will be used to perform dispersion corrections. Focussing lightguides will map propagation angles to spatial positions on the surface of photon detectors. Fast single photon detection devices will be used to measure azimuthal angles and spatial positions, which can be used to reconstruct kinematic properties of the passing particles. The expected average interaction rate of 20 MHz yields a photon detection rate of 1.3 MHz, as it is foreseen to use 128 MCP-PMT, each with 32 channels, for continuous readout. Moderate timing resolution of 300 ps improves signal from noise separation. The readout design requirements for the Focussing-Lightguide Disc DIRC will be introduced. The current candidate for implementation of the front-end readout electronic system will be described and several alternative readout scenarios will be discussed. Finally, a summary and an outlook for further developments and tests will be given.
120848137
The bar PANDA focussing-lightguide disc DIRC
ANDA will be a fixed target experiment internal to the HESR antiproton storage ring at the future FAIR complex. The ANDA detector requires excellent particle-identification capabilities in order to achieve its scientific potential. Cherenkov counters employing the DIRC principle were chosen as PID detectors for the Target Spectrometer. The proposed Focussing-Lightguide Disc DIRC will cover the forward part of the Target Spectrometer acceptance in the angular range between 5° and 22°. Its design includes a novel approach to mitigate dispersion effects in the solid radiator of a DIRC counter using optical elements. The dispersion correction will enable the Focussing-Lightguide Disc DIRC to provide pion-kaon identification for momenta well above 3.5 GeV/c.
54846524
Development of DIRC counters for the PANDA Experiment at FAIR
The PANDA experiment at the planned FAIR facility at GSI, Darmstadt, aims at measuring hadronic final states with unprecedented precision and luminosity. Superior particle identification of charged and neutral particles is mandatory to fulfil PANDA's physics aims. DIRC (Detection of Internally Reflected Cherenkov light) counters are foreseen for charged particle identification. A barrel DIRC will cover the central region while a disc DIRC will provide particle identification in the forward region. 
 
Three DIRC concepts differing in the radiator geometry and method for dispersion correction are studied. The barrel DIRC uses a novel imaging system and aims at exploiting a 3D reconstruction to mitigate dispersion effects. Two concepts are investigated for the forward disc DIRC. One concept employs passive dispersion correction and focussing light guides for image reconstruction. Alternatively, time-of-propagation measurements and a wave-length dependent photon detection system are investigated. The three detector designs share common developments such as investigating radiator properties and photon detection systems, and use the same test beam facilities.