Natalia Korotkova

Instrument for Exotic Particles Search in Cosmic Rays (INSTEPS)

An Instrument for an exotic particle search (INSTEPS) in cosmic rays is proposed for detailed investigation of cosmic ray flux in the charge region 0.5 - 2 minimum-ionizing particles (mip), where a few strange results have been registered. These results could not be understood because of poor charge resolution. There is also 0.1 - 0.5 mip region, which is practically unknown because of a limited signal to noise ratio. The instrument includes a set of self-triggered modules with 6 layers of 1 mm thick silicon microstrip detectors 10 x 10 cm^2 size for precise charge measurements. Every module can be also used as a separate device in many other experiments where precise charge determination is required. For exotic particle search a group of the charge measuring modules is placed on the top of a scintillator calorimeter. The calorimeter will measure particle energy and trajectory and generate a special trigger for the charge modules when the energy is above 50 GeV. This serves to decrease particle flux, because the already mentioned anomalies have been observed between high energy hadrons. We plan to expose the instrument at mountain level where it can register the particles that have arrived from space as well as those generated in the atmosphere.

SIDR Experiment status and first results

A two channel version of the SIDR (Solar Influence on Decay Rate) experiment setup is taking data in Yerevan (Armenia) and first results are presented. Two identical Sr-90 sources with scintillator detectors and fast electronics are permanently working at the Yerevan Physics Institute, located approximately 800 m above sea level. Every channel decay rate is 150 000/s. This gives us an opportunity to investigate rather fast rate changes with better than 0.1% accuracy for 10 s time intervals. The channels are synchronized, and the number of decays in each channel is recorded every 100 ms. This allows us to register correlations in rate changes between the channels, and also with various environmental events, with 1% accuracy per channel within 0.1 s.

Studies of the possibility to use Gas Pixel Detector as a fast trigger tracking device

Gas Pixel Detector (GPD) technology offers new possibilities, which make them very attractive for application in existing and future accelerator experiments and beyond. GPDs combine advantages of silicon and gaseous detectors. They can be produced radiation hard and with low power consumption using relatively cheap technology. Low capacitance of the individual pixel channel allows us to obtain a large signal to noise ratio. Using a time projection method for GPD readout one obtains 3D track image with precise coordinate (31 µm) and angular information (0.40°). This feature would allow us to achieve performance of one GPD layer equal to a few layers of silicon detectors. Implementation of a fast readout and data processing at the front-end level allows one to reconstruct a track segment in less than 1 μs, and to use this information for the first level trigger generation. The relevant algorithms of data acquisition and analysis are described and the results of simulations are presented in this paper.