Abstract The drift chambers of the HADES experiment at SIS-18 at GSI, Darmstadt/Germany, form the main tracking system of the spectrometer. Designed more than twenty years ago, the whole front-end ...electronics chain is being replaced with state-of-the-art electronics to cope with the increasing failure rate of the old electronics and with advanced requirements of the experiment, e.g. the trigger rate. The new analog signal processing is based on the PASTTREC ASIC, developed for the Straw Tube Tracker of the PANDA Experiment. The digitization of data happens in FPGA-based TDCs. The main challenges of the project are the strict spatial constraints given by the experiment setup to place the front-end boards and the noise sensitivity of the large area gas detectors. In addition, the power consumption needed to be kept low due to thermal constraints.
The ultra-thin and highly granular CMOS Monolithic Active Pixel Sensors (MAPS) are typically optimized for high rate high precision tracking, which implies the use of a very thin active medium and ...digital readout. Both features hamper using the devices for identifying low momentum particles by means of dE/dx. Still, MAPS feature charge sharing and typically clusters of more than one fired pixel per impinging particles are formed. It was previously shown that the number of fired pixels per cluster scales with the dE/dx, which allowed identifying highly ionizing nuclear fragments 1. Assuming a sufficiently strong response to different dE/dx, this approach could also be considered for distinguishing minimum ionizing particles (MIP) from light fragments like alpha particles in tracking detectors. In this work, we study this response with particle beams with a dE/dx of up to four times the ones of MIPs, for non-irradiated and irradiated chips, with different sensing nodes as implemented in the MIMOSIS-1 prototype used for the vertex detector of the CBM experiment.
Abstract
MIMOSIS is a CMOS Monolithic Active Pixel Sensor (CPS) developed to equip the Micro Vertex Detector (MVD) of the Compressed Baryonic Matter (CBM) experiment at FAIR/GSI. The sensor will ...combine a spatial resolution of -5 µm with a time resolution of 5 µs and provide a peak hit rate capability of ∼80 MHz/cm
2
. To fulfil its task, MIMOSIS will have to withstand ionising radiation doses of ∼5 MRad and fluences of ∼7 × 10
13
n
eq
/cm
2
per year of operation.
The paper summarises major requirements of the CBM-MVD and compares them to the detection performances of the first full scale prototype, called MIMOSIS-1, recently evaluated in the laboratory and with particle beams. The tolerance of the sensor to the expected ionising radiation load was evaluated; the paper describes the measurements performed and their outcome.
Abstract
Being installed as close as 5.5 mm to the beam axis, the Micro Vertex Detector (
mvd
) of the
cbm
experiment will be exposed to a sizable flow of heavy beam ions and nuclear fragments. The
...cmos
Monolithic Active Pixel Sensor for the
mvd, mimosis
, must resist the related heavy ion impacts without permanent damage or frequent interrupt of operation as caused by single event effects (
see
). We motivate the requirements on the sensor and introduce our concept for protecting the device against
see
s. Moreover, we report the results of a related test campaign carried out with the first full size sensor prototype,
mimosis
-1, and different heavy ion beams at
gsi
.
The HADES collaboration uses the e
+
e
−
production as a probe of the resonance matter produced in collisions at incident energies of 1-3.5 GeV/nucleon at GSI. Elementary reactions provide useful ...references for these studies and give information on resonance Dalitz decays (R→Ne
+
e
−
). Such processes are sensitive to the structure of time-like electromagnetic baryon transitions in a kinematic range where (off-shell) vector mesons play a crucial role. Results obtained in proton-proton reactions and in a commissioning pion-beam experiment are reported and prospects for future pion beam experiments and for first hyperon Dalitz decay measurements are described. The connection with the investigations of medium effects to be continued with HADES in the next years at SIS18 and SIS100 is also discussed.
A first generation prototype for the CBM micro vertex detector Deveaux, M.; Amar-Youcef, S.; Fröhlich, I. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2013, Letnik:
718
Journal Article
Recenzirano
The Compressed Baryonic Matter (CBM) experiment will be a fixed target heavy ion experiment at the future FAIR facility in Darmstadt, Germany. Its Micro Vertex Detector (MVD) is to identify open ...charm particles in the rich background of 15–35AGeV heavy ion collisions. We show a concept how to match the required combination of high rate capability and excellent secondary vertex resolution and discuss the status of the MVD prototype.
CMOS Monolithic Active Pixel Sensors (MAPS) demonstrated excellent performances in the field of charged particle tracking. Among their strong points are an single point resolution few μm, a light ...material budget of 0.05% X0 in combination with a good radiation tolerance and high rate capability. Those features make the sensors a valuable technology for vertex detectors of various experiments in heavy ion and particle physics. To reduce the load on the event builders and future mass storage systems, we have developed algorithms suited for preprocessing and reducing the data streams generated by the MAPS. This real-time processing employs remaining free resources of the FPGAs of the readout controllers of the detector and complements the on-chip data reduction circuits of the MAPS.
CMOS Monolithic Active Pixel Sensors (MAPS) demonstrated excellent performances in the field of charged particle tracking. They feature an excellent single point resolution of few μm, a light ...material budget of 0.05% Xo in combination with a good radiation tolerance and time resolution. This makes the sensors a valuable technology for micro vertex detectors (MVD) of various experiments in heavy ion and particle physics like STAR and CBM. State of the art MAPS are equipped with a rolling shutter readout. Therefore, the data of one individual event is typically found in more than one data train generated by the sensor. This paper presents a concept to introduce this feature in both simulation and data analysis, taking profit of the sensor topology of the MVD. This topology allows to use for massive parallel data streaming and handling strategies within the FairRoot framework.
CMOS Monolithic Active Pixel Sensors (MAPS) demonstrate excellent performances in the field of charged particle tracking. A single point resolution of 1--2 mu m and a detection efficiency close to ...100% were routinely observed with various MAPS designs featuring up to 10 super(6) pixels on active areas as large as 4 cm super(2)1. Those features make MAPS an interesting technology for vertex detectors in particle and heavy ion physics. In order to adapt the sensors to the high particle fluxes expected in this application, we designed a sensor with fast column parallel readout and partially depleted active volume. The latter feature was expected to increase the tolerance of the sensors to non-ionizing radiation by one order of magnitude with respect to the standard technology. This paper discusses the novel sensor and presents the results on its radiation tolerance.
The unexplained disagreement in the dependence of spectroscopic factors ( C 2 S exp ) on the binding energy obtained by nucleon knockout using different targets is still a puzzle that needs to be ...addressed. To find an explanation of this riddle through exclusive measurements using different targets. The exclusive measurements were performed by using a Ne 17 beam with an energy of 500 MeV/u incident on C and CH 2 targets. Through the standard theoretical approach, C 2 S exp were derived from the analysis of the experimental data on proton ejection from the proton halo in Ne 17 as well as from its core O 15 . For the C target, proton ejection from the proton halo gave C 2 S exp about 37% smaller than for the H target. But when protons are ejected from the core of Ne 17 , C 2 S exp are identical within statistical uncertainties. An explanation for the difference in C 2 S exp could be the removal of both halo protons, a more important reaction pathway for the C target. The C 2 S exp values obtained by analyzing the proton ejection from the core indicate that it is not affected by the interaction with the halo protons. Published by the American Physical Society 2024
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