The Liquid Argon Jet Trigger of the H1 Experiment at HERA

We report on a novel trigger for the liquid argon calorimeter which was installed in the H1 Experiment at HERA.This trigger, called the “Jet Trigger”, was running at level 1 and implemented a real-time cluster algorithm. Within only 800 ns, the Jet Trigger algorithm found local energy maxima in the calorimeter, summed their immediate neighbors, sorted the resulting jets by energy, and applied topological conditions for the final level 1 trigger decision. The Jet Trigger was in operation from the year 2006 until the end of the HERA running in the summer of 2007. With the Jet Trigger it was possible to substantially reduce the thresholds for triggering on electronsand jets, giving access to a largely extended phase space for physical observables which could not have been reached in H1 before. The concepts of the Jet Trigger may be an interesting upgrade option for the LHC experiments

Electron Identification with a Prototype of the Transition Radiation Tracker for the ATLAS experiment

A prototype of the Transition Radiation Tracker (TRT) for the ATLAS detector at the LHC has been built and tested. The TRT is an array of straw tubes which integrate tracking and electron identification by transition radiation into one device. Results of experimental measurements and of comparisons with Monte Carlo simulations are presented for the electron identification performance as a function of various detector parameters. Under optimal operating conditions, a rejection against pions of a factor 100 was achieved with 90\% electron efficiency

Quadrupole collectivity in Ca 42 from low-energy Coulomb excitation with AGATA

A Coulomb-excitation experiment to study electromagnetic properties of Ca42 was performed using a 170-MeV calcium beam from the TANDEM XPU facility at INFN Laboratori Nazionali di Legnaro. γ rays from excited states in Ca42 were measured with the AGATA spectrometer. The magnitudes and relative signs of ten E2 matrix elements coupling six low-lying states in Ca42, including the diagonal E2 matrix elements of 21+ and 22+ states, were determined using the least-squares code gosia. The obtained set of reduced E2 matrix elements was analyzed using the quadrupole sum rule method and yielded overall quadrupole deformation for 01,2+ and 21,2+ states, as well as triaxiality for 01,2+ states, establishing the coexistence of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in Ca42. The experimental results were compared with the state-of-the-art large-scale shell-model and beyond-mean-field calculations, which reproduce well the general picture of shape coexistence in Ca42

Superdeformed and Triaxial States in Ca 42

Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in ^{42}Ca were determined from E2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 0_{2}^{+} has been obtained and the role of triaxiality in the A∼40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time

Assessment of exposure to X - rays during patient positioning at the proton eye radiotherapy facility at IFJ PAN, Kraków

At the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN, Kraków, Poland) the proton eye radiotherapy facility has recently been developed and is now fully operational. A set of two X-ay RAD-14 Varian medical systems tubes are used to obtain orthogonal images of the patient’s eyeball undergoing radiotherapy with tantalum clips already attached to its surface to delineate the tumour volume. We assessed the dose received by the patient from multiple X-ray exposures during the patient positioning procedure. Measurements of Kair were performed using various types of ionization chambers and MCP-N thermoluminescent (TL) detectors and calculated using the PCXMC code. Good agreement between measurements and calculations was found. The mean absorbed dose to the brain was measured using TL detectors placed inside the head of a Rando anthropomorphic phantom used in simulation of the patient positioning procedure. The measured maximum incident air kerma absorbed during the entire procedure of patient positioning was found not to exceed 7 mGy, while the mean absorbed dose to the brain did not exceed 2 mSv

Silicon ultra fast cameras for electron and gamma sources in medical applications: a progress report

SUCIMA (Silicon Ultra fast Cameras for electron and gamma sources In Medical Applications) is a project approved by the European Commission within the Fifth Framework Programme, with the primary goal of developing a real time dosimeter based on direct detection of ionising particles in a position sensitive Silicon sensor. The main applications of this device are imaging of intravascular brachytherapy radioactive sources with-activities up to 3 GBq and real time monitoring of hadrontherapy beams. In order to perform a feasibility study, during the first two years a real time dosimeter has been engineered using Silicon microstrip detectors read out by an integrating dead-timeless front-end electronics. The prototypes have been qualified as relative dosimeter with respect to certified secondary standards; moreover, further measurements are on going in order to investigate the possibility to use the sensors as absolute dosimeters. Since the final device is supposed to provide a two dimensional image, two different Monolithic Active Pixel dosimeters have been designed and produced by the collaboration based on CMOS and Silicon On Insulator technologies. The main features of the two sensors are presented in this paper