Currently, the HADES spectrometer undergoes un upgrade program to be prepared for measurements at the upcoming SIS-100 synchrotron at FAIR. We describe the current status of the HADES di-electron measurements at the SIS-18 and our future plans for SIS-100.
The TRB hardware module is a multi-purpose Trigger and Readout Board with on-board DAQ functionality developed for the upgrade of the HADES experiment. It contains a single computer chip (Etrax) running Linux as a well as a 100 Mbit/s Ethernet interf
ace. It has been orginally designed to work as a 128-channel Time to Digital Converter based on the HPTDC chip from CERN. The new version contains a 2 Gbit/s optical link and an interface connector (15 Gbit/s) in order to realize an add-on card concept which makes the hardware very flexible. Moreover, an FPGA chip (Xilinx, Virtex 4 LX 40) and a TigerSharc DSP provide new computing resources which can be used to run on-line analysis algorithms. The TRB is proposed as a prototype for new modules for the planned detector systems PANDA and CBM at the future FAIR facility at GSI-Darmstadt.
The Facility for Antiproton and Ion Research (FAIR) is an international accelerator facility which will use antiprotons and ions to perform research in the fields of nuclear, hadron and particle physics, atomic and anti-matter physics, high density p
lasma physics and applications in condensed matter physics, biology and the bio-medical sciences. It is located at Darmstadt (Germany) and it is under construction. Among all projects in development at FAIR in this moment, this report focuses on the $bar PANDA$ experiment (antiProton ANnihilation at DArmstadt). Some topics from the Charm and Charmonium physics program of the $bar PANDA$ experiment will be highlighted, where $bar PANDA$ is expected to provide first measurements and original contributions, such as the measurement of the width of very narrow states and the measurements of high spin particles, nowaday undetected. The technique to measure the width of these very narrow states will be presented, and a general overview of the machine is provided.
A feasibility study has been performed in order to investigate the performance of the HADES detector to measure the electromagnetic decays of the hyperon resonances $Sigma(1385)^0$, $Lambda(1405)$ and $Lambda{Lambda}(1520)$ as well as the production
of double strange baryon systems $Xi^-$ and $LambdaLambda$ in p+p reactions at a beam kinetic energy of 4.5 GeV. The existing HADES detector will be upgraded by a new Forward Detector, which extends the detector acceptance into a range of polar angles that plays a crucial role for these investigations. The analysis of each channel is preceded by a consideration of the production cross-sections. Afterwards the expected signal count rates using a target consisting of either liquid hydrogen or polyethylene are summarized.
The centrality determination for Au+Au collisions at 1.23A GeV, as measured with HADES at the GSI-SIS18, is described. In order to extract collision geometry related quantities, such as the average impact parameter or number of participating nucleons
, a Glauber Monte Carlo approach is employed. For the application of this model to collisions at this relatively low centre-of-mass energy of $sqrt{s_{mathrm{NN}}} = 2.42$ GeV special investigations were performed. As a result a well defined procedure to determine centrality classes for ongoing analyses of heavy-ion data is established.
In pp collisions at 1.25 GeV kinetic energy, the HADES collaboration aimed at investigating the di-electron production related to $Delta$ (1232) Dalitz decay ($Delta^+ to pe^+e^-$). In order to constrain the models predicting the cross section and th
e production mechanisms of $Delta$ resonance, the hadronic channels have been measured and studied in parallel to the leptonic channels. The analyses of $ppto nppi^+$ and $ppto pppi^0$ channels and the comparison to simulations are presented in this contribution, in particular the angular distributions being sensitive to $Delta$ production and decay. The accurate acceptance corrections have been performed as well, which could be tested in all the phase space region thanks to the high statistic data. These analyses result in an overall agreement with the one-$pi$ exchange model and previous data.