Czech Contribution to LOFT

We describe the current status of the Czech contribution to the ESA LOFT space mission, with emphasis on technical aspects. Expertise available in the Czech Republic will play a positive role in the LOFT project and related developments

Vytvoření komplexního informačního systému integrované prevence v ČR

Výsledkem projektu bude funkční řádně dokumentovaný informační systém, který zajistí potřeby resortních organizací, orgánů státní a veřejné správy, odborné i laické veřejnosti v oblasti poskytování informací o stavu životního prostředí. Bude podporovat poskytování reportingových zpráv pro EU i pro další účely. V rámci jednotlivých krajů byly shromážděny veřejně dostupné informace o prevenci závažných havárií. Byl shrnut legislativní rámec pro danou problematiku. Byl vypracován rejstřík chemických látek, který obsahuje cca 900 druhů chemických látek klasifikovaných do skupin podle vybraných nebezpečných vlastností uvedených v zákoně č. 59/2006 Sb. Při návštěvách krajských úřadů bylo provedeno šetření stávajícího stavu zařazených a nezařazených podniků do systému integrované prevence. Proběhlo dotazníkové šetření s cílem popsat činnosti státní správy v oblasti prevence závažných havárií. Byly vedeny diskuse s pracovníky úřadů o způsobech vedení evidence, jejích nedostatcích, možných vylepšeních současného stavu a o potenciálních výstupech projektu. Především k výstupům z těchto jednání by mělo být při tvorbě informačního systému přihlíženo. Zpráva obsahuje v příloze i vlastní dotazníky

Towards the first measurement of matter-antimatter gravitational interaction

The AEgIS (Antimatter Experiment: Gravity, Interferometry, Spectroscopy) is a CERN based experiment with the central aim to measure directly the gravitational acceleration of antihydrogen. Antihydrogen atoms will be produced via charge exchange reactions which will consist of Rydberg-excited positronium atoms sent to cooled antiprotons within an electromagnetic trap. The resulting Rydberg antihydrogen atoms will then be horizontally accelerated by an electric field gradient (Stark effect), they will then pass through a moiré deflectometer. The vertical deflection caused by the Earth's gravitational field will test for the first time the Weak Equivalence Principle for antimatter. Detection will be undertaken via a position sensitive detector. Around 103 antihydrogen atoms are needed for the gravitational measurement to be completed. The present status, current achievements and results will be presented, with special attention toward the laser excitation of positronium (Ps) to the n=3 state and the production of Ps atoms in the transmission geometry

Antiproton tagging and vertex fitting in a Timepix3 detector

Studies of antimatter are important for understanding our universe at a fundamental level. There are still unsolved problems, such as the matter-antimatter asymmetry in the universe. The AEgIS experiment at CERN aims at measuring the gravitational fall of antihydrogen in order to determine the gravitational force on antimatter. The proposed method will make use of a position-sensitive detector to measure the annihilation point of antihydrogen. Such a detector must be able to tag the antiproton, measure its time of arrival and reconstruct its annihilation point with high precision in the vertical direction. This work explores a new method for tagging antiprotons and reconstructing their annihilation point. Antiprotons from the Antiproton Decelerator at CERN were used to obtain data on direct annihilations on the surface of a silicon pixel sensor with Timepix3 readout. These data were used to develop and verify a detector response model for annihilation of antiprotons in this detector. Using this model and the antiproton data it is shown that a tagging efficiency of 50± 10% and a vertical position resolution of 22 ± 0.5 μm can be obtained

Producing long-lived 2 3S positronium via 3 3P laser excitation in magnetic and electric fields

Producing positronium (Ps) in the metastable 2 3 S state is of interest for various applications in fundamental physics. We report here on an experiment in which Ps atoms are produced in this long-lived state by spontaneous radiative decay of Ps excited to the 3 3 P level manifold. The Ps cloud excitation is obtained with a UV laser pulse in an experimental vacuum chamber in presence of guiding magnetic field of 25 mT and an average electric field of 300 V cm−1. The evidence of the 2 3 S state production is obtained to the 3.6σ level of statistical significance using a novel analysis technique of the single-shot positronium annihilation lifetime spectra. The dynamic of the Ps population on the involved levels has been studied with a rate equation model

Antiproton tagging and vertex fitting in a Timepix3 detector

Studies of antimatter are important for understanding our universe at a fundamental level. There are still unsolved problems, such as the matter-antimatter asymmetry in the universe. The AEgIS experiment at CERN aims at measuring the gravitational fall of antihydrogen in order to determine the gravitational force on antimatter. The proposed method will make use of a position-sensitive detector to measure the annihilation point of antihydrogen. Such a detector must be able to tag the antiproton, measure its time of arrival and reconstruct its annihilation point with high precision in the vertical direction. This work explores a new method for tagging antiprotons and reconstructing their annihilation point. Antiprotons from the Antiproton Decelerator at CERN were used to obtain data on direct annihilations on the surface of a silicon pixel sensor with Timepix3 readout. These data were used to develop and verify a detector response model for annihilation of antiprotons in this detector. Using this model and the antiproton data it is shown that a tagging efficiency of 50± 10% and a vertical position resolution of 22 ± 0.5 μm can be obtained

The AEgIS Experiment

The AEgIS experiment aims at performing the first test of the Weak Equivalence Principle of General Relativity in the antimatter sector by measuring the gravitational acceleration acting on a beam of cold antihydrogen to a precision of 1%. The installation of the apparatus is making good progress and large parts were taken into operation. Parasitic detector tests during the beamtime in December 2012 gave essential input for an optimal moiré deflectometer and the detector layout necessary to perform the gravity measurement.ISSN:0304-3843ISSN:0304-3834ISSN:1572-954