H. J. Simonis

The Belle detector at the KEKB electron-positron collider has collected almost 1 billion Y(4S) events in its decade of operation. Super-KEKB, an upgrade of KEKB is under construction, to increase the luminosity by two orders of magnitude during a three-year shutdown, with an ultimate goal of 8E35 /cm^2 /s luminosity. To exploit the increased luminosity, an upgrade of the Belle detector has been proposed. A new international collaboration Belle-II, is being formed. The Technical Design Report presents physics motivation, basic methods of the accelerator upgrade, as well as key improvements of the detector.

The recently introduced gas electron multiplier (GEM) permits the amplification of electrons released by ionizing radiation in a gas by factors approaching ten thousand; larger gains can be obtained combining two GEMs in cascade. We describe methods for implementing two- and three-dimensional projective localization of radiation, with sub-millimeter accuracy, making use of specially manufactured and patterned pick-up electrodes. Easy to implement and flexible in the choice of the readout geometry, the technology has the distinctive advantage of allowing all pick-up electrodes to be kept at ground potential, thus substantially improving the system simplicity and reliability. Preliminary results demonstrating the two-dimensional imaging capability of the devices are provided and discussed, as well as future perspectives of development.

A new extensive air shower (EAS) experiment has been installed at the laboratory site of the Forschungszentrum Karlsruhe. The main aim of the KASCADE [1] project is the determination of the chemical composition in the energy range around and above the knee of the primary cosmic ray spectrum. The main advantage of the new installation is the simultaneous measurement of a large number of observables for each individual event. This is achieved by the combination of various advanced detection techniques for the electromagnetic, the muonic, and the hadronic component of the extensive air showers. Data taking with a large part of the experiment has started at the end of 1995. The estimated accuracy of air shower data is discussed for the various detector components of KASCADE and first very preliminary results are presented.

The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $\mathrm{\mathbf{\mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $\mathbf{e^+ e^-}$ collider.

Measurements of transient magnetic fields for Coulomb-excited 28Si(2+) and 62Ni(2+) ions recoiling in Fe(Gd) host with high and low velocity, respectively, gave clear evidence that the field strengths are substantially reduced due to momentary loss in ferromagnetism when using Ni-beams for excitation. There are strong indications that many earlier measurements suffered from the same effect and must be therefore reviewed.

A beam telescope based on the CMS Tracker data acquisition prototype cards has been developed in order to test sensor candidates for S-LHC tracking systems. The telescope consists of up to eight reference silicon microstrip modules and slots for a couple of test modules. Beam tracks, as measured by the reference modules, provide a means of determining the position resolution and efficiency of the test modules. The impact point precision of reference tracks at the location of the test modules is about 4μm. This note presents a detailed description of the silicon beam telescope (SiBT) along with some results from its initial operation in summer 2007 in the CERN H2 beamline.

Geant4 low energy extensions have been used to simulate the X-ray spectra of industrial X-ray tubes with filters for removing the uncertain low energy part of the spectrum in a controlled way. The results are compared with precisely measured X-ray spectra using a silicon drift detector. Furthermore, this paper shows how the different dose rates in silicon and silicon dioxide layers of an electronic device can be deduced from the simulations.

Strip detectors with an area of 16cm2 were processed on high resistivity n-type magnetic Czochralski silicon. In addition, detectors were processed on high resistivity Float Zone wafers with the same mask set for comparison. The detectors were irradiated to several different fluences up to the fluence of 3×10151MeVneq/cm2 with protons or with mixed protons and neutrons. The detectors were fully characterized with CV- and IV-measurements prior to and after the irradiation. The beam test was carried out at the CERN H2 beam line using a silicon beam telescope that determines the tracks of the incoming particles and hence provides a reference measurement for the detector characterization. The n-type MCz-Si strip detectors have an acceptable S/N at least up to the fluence of 1×1015neq/cm2 and thus, they are a feasible option for the strip detector layers in the SLHC tracking systems.

Pad and strip detectors processed on high resistivity n-type magnetic Czochralski silicon (MCz-Si) were irradiated to several different fluences with protons.The pad detectors were characterized with the Transient Current Technique (TCT) and the full-size strip detectors with a reference beam telescope and a 225 GeV muon beam.The TCT measurements indicate a double junction structure and space charge sign inversion in MCz-Si detectors after 6 × 10 14 1 MeV n eq /cm 2 fluence.In the beam test a S/N of 50 was measured for a non-irradiated MCz-Si sensor, and a S/N of 20 for the sensors irradiated to the fluences of 1 × 10 14 1 MeV n eq /cm 2 , and 5 × 10 14 1 MeV n eq /cm 2 .

With an expected 10-fold increase in luminosity in S-LHC, the radiation environment in the tracker volumes will be considerably harsher for silicon-based detectors than the already harsh LHC environment. Since 2006, a group of CMS institutes, using a modified CMS DAQ system, has been exploring the use of Magnetic Czochralski silicon as a detector element for the strip tracker layers in S-LHC experiments. Both p+/n-/n+ and n+/p-/p+ sensors have been characterized, irradiated with proton and neutron sources, assembled into modules, and tested in a CERN beamline. There have been three beam studies to date and results from these suggest that both p+/n-/n+ and n+/p-/p+ Magnetic Czochralski silicon are sufficiently radiation hard for the R>25cm regions of S-LHC tracker volumes. The group has also explored the use of forward biasing for heavily irradiated detectors, and although this mode requires sensor temperatures less than −50 °C, the charge collection efficiency appears to be promising.

A large transient magnetic field (TF) of BTF = 621(108) T was found for Ne ions traversing Gd at vion = 3.1v0 (v0 = c137). The measurements were performed using the (α, α') reaction on Ne targets. Contrary to a previous measurement the beam-bending at the 2+ and 4+ resonances in the 12C(12C, α) reaction at bombarding energies of 34.7 MeV and 32.6 MeV, respectively, was found to be the same and small in magnitude. A critical assessment of all g-factor measurements of the 20Ne(4+) state is given.

Large transient magnetic fields have been observed for single-electron O ions for short interaction times of 10 fs and 100 fs passing through thin magnetized Gd layers. The derived value for the degree of polarization, p¯1s=0.26(1), demonstrates that the polarization transfer cross sections are large enough to generate in very short times substantial polarization of 1s electrons in these ions.

Spin polarization of $1s$ electrons has been observed for single-electron F ions on emergence from magnetized thin Fe layers into vacuum by use of the perturbed-angular-correlation technique on the isomeric $^{19}\mathrm{F}$(5/${2}^{+}$) state as a probe. The mean degree of polarization observed, ${p}_{1s}=0.10(3)$, is consistent with values relevant to measurements of transient magnetic fields.

Transient field precessions have been measured with the first excited 2 1 + -state as probe for ions of28Si traversing Fe at vion−1v0 and 13v0(v0=c/137) and62Ni being stopped in Fe. The degree of polarization deduced for the Si ions, p1s=0.19(6), is consistent with low-velocity data. There is clear evidence that the field strength is attenuated by heavy ion beams. For the62Ni(2 1 + ) state at 1.173 MeV a g-factor value of g=0.34(7) was obtained in good agreement with a previous result.

The construction of a micro-pattern gas detector of dimensions 40×10cm2 is described. Two gas electron multiplier foils (GEM) provide the internal amplification stages. A two-layer readout structure was used, manufactured using the same technology as the GEM foils. The strips of each layer cross at an effective crossing angle of 6.7° and have a 406μm pitch. The performance of the detector has been evaluated in a muon beam at CERN using a silicon telescope as reference system. The position resolutions of two orthogonal coordinates are measured to be 50μm and 1mm, respectively. The muon detection efficiency for two-dimensional space points reaches 96%.

The CMS Tracker is the world's largest silicon detector. It has only recently been moved underground and installed in the 4 T solenoid. Prior to this there has been an intensive testing on the surface, which confirms that the detector system fully meets the design specifications. Irradiation studies with the sensor material shows that the system will survive for at least 10 years in the harsh radiation environment prevailing within the Tracker volume. The planning phase for SLHC as the successor of LHC, with a 10 times higher luminosity at the same energy has already begun. First R&D studies for more robust detector materials and a new Tracker layout have started.

Spin precessions in transient magnetic fields (TF) have been measured with the 16O(3−) state as probe for oxygen ions recoiling through localized helium layers implanted into thin iron foils. Precession angles are determined to high precision for different foil thicknesses. The data can be understood only if one assumes that the TF is not operative over the helium implanted region of the ferromagnetic foil. This behaviour indicates that the iron lattice is severely damaged and loses magnetic properties by the implantation process.

Abstract A system of detector modules consisting of a large size Gas Electron Multiplier (GEM), coupled to Micro Strip Gas Counters (MSGC), has been exposed to a pion beam at the Paul Scherrer Institute Cyclotron facility. As part of a CMS tracker milestone, the aim of this test was to investigate the robustness of such detectors when exposed to experimental conditions close to what is expected at the Large Hadron Collider (LHC) of CERN. Eighteen detector modules have been operated at voltage settings corresponding to 98% detection efficiency for Minimum Ionizing Particles during a period of 5 weeks. Sparking rates and strip losses have been monitored throughout the exposure. An operation margin of at least a factor of three with respect to the required gas gain has been demonstrated.

Abstract As a result of the high luminosity phase of the SLHC, for CMS a tracking system with very high granularity is mandatory and the sensors will have to withstand an extreme radiation environment of up to 10 16  part/ 2 . On this basis, a new geometry with silicon short strip sensors (strixels) is proposed. To understand their performances, test geometries are developed whose parameters can be verified and optimized using simulation of semiconductor structures. We have used the TCAD-ISE (SYNOPSYS package) software in order to simulate the main electrical parameters of different strip geometries, for p-in-n-type wafers.

Precessions of the very short-lived 2 1 + - and 4 1 + -states in32S have been measured using the transient field technique. The deducedg-factor of the 4 1 + -state g=+0.40(15) agrees with the known value of the 2 1 + -state and with theoretical predictions. In addition, the lifetimes of both states were redetermined and are consistent with previous results.

In order to check the system aspects of the forward–backward MSGC tracker designed for the future CMS experiment at LHC, 38 trapezoidal MSGC counters assembled in six multi-substrates detector modules were built and exposed to a muon beam at the CERN SPS. Results on the gain uniformity along the wedge-shaped strip pattern and across the detector modules are shown together with measurements of the detection efficiency and the spatial resolution.

A small series production of detector modules made of MicroStrip Gas Counters (MSGC) and a Gas Electron Multiplier (GEM) foil has been exposed to a high-intensity hadron beam. We report about the reproductibility and stability of the detector responses and about the occurrence and consequences of discharges in the detector. The interdependence of the four voltage differences used in the detector has been studied by simulation and with X-ray measurements. Rate dependence of the signal amplitude is observed. The behaviour of the MSGC+GEM is compared to that of a state-of-the-art MSGC. Influence of various parameters on the detector response is investigated.

In time-differential measurements it is shown that 1s electrons of single-electron 16O(3−) ions have their spin polarized on emergence from magnetized thin Fe foils into vacuum. The mean degree of polarization deduced, p1s=0.060(6), is approximately half of what is observed inside the Fe foil.

[Theg-factor ratio of the first excited 3− and 5− states in40Ca was measured to beg 3/g 5=1.01(10) employing the implantation perturbed angular correlation technique. The static hyperfine fields (SF) in Fe and Gd hosts were used. In addition the lifetime of the 5− state was measured to be τ=426(7)ps. The values of the SF in Gd and Fe hosts were deduced and compared with systematics in this element region.

Abstract The start of the High-Luminosity LHC (HL-LHC) in 2027 requires upgrades to the Compact Muon Solenoid (CMS) experiment. In the scope of the upgrade program the complete silicon tracking detector will be replaced. The new CMS Tracker will be equipped with silicon pixel detectors in the inner layers closest to the interaction point and silicon strip detectors in the outer layers. The new CMS Outer Tracker will consist of two different kinds of detector modules called PS and 2S modules. Each module will be made of two parallel silicon sensors (a macro-pixel sensor and a strip sensor for the PS modules and two strip sensors for the 2S modules). Combining the hit information of both sensor layers, it is possible to estimate the transverse momentum of particles in the magnetic field of 3.8 T at the full bunch-crossing rate of 40 MHz directly on the module. This information will be used as an input for the first trigger stage of CMS. It is necessary to validate the Outer Tracker module functionality before installing the modules in the CMS experiment. Besides laboratory-based tests several 2S module prototypes have been studied at test beam facilities at CERN, DESY and FNAL. This article concentrates on the beam tests at DESY during which the functionality of the module concept was investigated using the full final readout chain for the first time. Additionally the performance of a 2S module assembled with irradiated sensors was studied. By choosing an irradiation fluence expected for 2S modules at the end of HL-LHC operation, it was possible to investigate the particle detection efficiency and study the trigger capabilities of the module at the beginning and end of the runtime of the CMS experiment.

We report on the performance of a large micro-pattern detector with two gas electron multiplier foils and a two-layer readout structure at ground potential. The two readout layers each have a 406μm pitch and cross at an effective angle of 6.7°. This structure allows for two orthogonal coordinates to be determined. Using a muon beam at CERN together with a silicon tracking system, the position resolutions of the two coordinates are measured to be 50μm and 1 mm respectively (1 standard deviation). The muon detection efficiency for the two-dimensional space points reaches 96%. The detector was found to be well operational over a wide range in the settings of the different electrical fields.

A large part of the inner tracker of CMS will be equipped with Micro Strip Gas Chambers (MSGCs). In addition to a high MIP rate these detectors also will be exposed to highly ionizing particles (HIP), as well as to a considerable flux of low-energy neutrons. We have performed experiments with neutrons in the energy range of 0.3–2 MeV, which covers the main part of the neutron spectrum prevailing within the CMS tracker volume. By means of time-of-flight a clear discrimination of the detector response to photons and neutrons has been achieved. The most probable neutron energy deposit has been found to be equivalent to 30 MIPs with a conversion probability of ε=10−5. Two MSGCs, one based on bare glass and another on diamond-like coated glass, were irradiated with neutrons at high dose (4×107 n/cm2 s). After an integral dose of 1×1013 n/cm2, equivalent to one LHC-year, no indication of damage could be found.

Seit 1983 wird am Universitätsklinikum Freiburg eine Tumorbasisdokumentation nach den Richtlinien der Arbeitsgemeinschaft Deutscher Tumorzentren (ADT) durchgefuhrt. Bis zum Juni 1989 wurden knapp 13.000 Patienten dokumentiert. Die Daten zu den am Tumorzentrum häufigsten Malignomlokalisationen wurden ausgewertet: Mamma, Cervix uteri, Corpus uteri, Ovar, Kolon und Rektum, Magen, Lunge und Prostata. Die Tumorbasisdokumentation dieser Malignome ist im Vergleich mit der Diagnosenstatistik nach der Bundespflegesatzverordnung zu etwa 80% vollständig und kann als repräsentativ für das Klinikkollektiv bezeichnet werden, da ein Selektionsbias bei den vorhandenen Patientenmerkmalen nicht beobachtet werden konnte.