41 research outputs found
Nuclear Charge Radius of Be
The nuclear charge radius of Be was precisely determined using the
technique of collinear laser spectroscopy on the transition in the Be ion. The mean square charge radius increases
from Be to Be by \delta ^{10,12} = 0.69(5) \fm^{2}
compared to \delta ^{10,11} = 0.49(5) \fm^{2} for the
one-neutron halo isotope Be. Calculations in the fermionic molecular
dynamics approach show a strong sensitivity of the charge radius to the
structure of Be. The experimental charge radius is consistent with a
breakdown of the N=8 shell closure.Comment: 5 pages, 3 figure
Timing and tracking for the Crystal Barrel detector
The aim of the project D.3 is the upgrade of several detector components used in the CBELSA/TAPS experiment at ELSA. The readout of the Crystal Barrel Calorimeter will be extended by a timing branch in order to gain trigger capability for the detector, which will allow to measure completely neutral final states in photoproduction reactions (see projects A.1 and C.5). Additionally, the readout of the inner crystals of the TAPS detector, which covers the forward opening of the Crystal Barrel Calorimeter, will be modified to be capable of high event rates due to the intensity upgrade of ELSA. Furthermore, a full-scale prototype Time Projection Chamber (TPC) has been built to be used as a new central tracker for the CBELSA/TAPS experiment at ELSA and the FOPI experiment at GSI
Research campaign : macroscopic quantum resonators (MAQRO)
The objective of the proposed macroscopic quantum resonators (MAQRO) mission is to harness space for achieving long free-fall times, extreme vacuum, nano-gravity, and cryogenic temperatures to test the foundations of physics in macroscopic quantum experiments at the interface with gravity. Developing the necessary technologies, achieving the required sensitivities and providing the necessary isolation of macroscopic quantum systems from their environment will lay the path for developing novel quantum sensors. Earlier studies showed that the proposal is feasible but that several critical challenges remain, and key technologies need to be developed. Recent scientific and technological developments since the original proposal of MAQRO promise the potential for achieving additional science objectives. The proposed research campaign aims to advance the state of the art and to perform the first macroscopic quantum experiments in space. Experiments on the ground, in micro-gravity, and in space will drive the proposed research campaign during the current decade to enable the implementation of MAQRO within the subsequent decade
Timing and tracking for the Crystal Barrel detector
The aim of the project D.3 is the upgrade of several detector components used in the CBELSA/TAPS experiment at ELSA. The readout of the Crystal Barrel Calorimeter will be extended by a timing branch in order to gain trigger capability for the detector, which will allow to measure completely neutral final states in photoproduction reactions (see projects A.1 and C.5). Additionally, the readout of the inner crystals of the TAPS detector, which covers the forward opening of the Crystal Barrel Calorimeter, will be modified to be capable of high event rates due to the intensity upgrade of ELSA. Furthermore, a full-scale prototype Time Projection Chamber (TPC) has been built to be used as a new central tracker for the CBELSA/TAPS experiment at ELSA and the FOPI experiment at GSI
Timing and tracking for the Crystal Barrel detector
The aim of the project D.3 is the upgrade of several detector components used in the CBELSA/TAPS experiment at ELSA. The readout of the Crystal Barrel Calorimeter will be extended by a timing branch in order to gain trigger capability for the detector, which will allow to measure completely neutral final states in photoproduction reactions (see projects A.1 and C.5). Additionally, the readout of the inner crystals of the TAPS detector, which covers the forward opening of the Crystal Barrel Calorimeter, will be modified to be capable of high event rates due to the intensity upgrade of ELSA. Furthermore, a full-scale prototype Time Projection Chamber (TPC) has been built to be used as a new central tracker for the CBELSA/TAPS experiment at ELSA and the FOPI experiment at GSI
Characterization and Applications of New High Quality LuAG:Ce and LYSO:Ce fibers
Inorganic scintillating fibers have a large potential as highly granular detector components in hadron and particle physics as well as in medical applications. With the micropulling-down-method a fast and cost efficient technique was developed over the last decades to grow such fibers from the melt. This paper will present the recent development of the quality of LuAG:Ce and LYSO:Ce fibers in terms of light output and light attenuation inside the fiber. For this purpose different steps in optimizing the fiber growth will be compared with the achieved fiber performance. In addition the response of the fibers to low energetic gamma rays will be studied and different readout concepts for the fibers will be discussed and compared
Regeneration of baroafferents after implantation into different vessels
Regeneration of peripheral nerves involves an essential contribution by surrounding tissues. This study focuses on the role of the target tissue on the regeneration of afferent peripheral nerves. We hypothesized that nerves implanted into the appropriate target tissue regain their function, whereas they degenerate when implanted into a different tissue. Therefore, aortic nerves of rabbits were transected and implanted into arteries or veins, and their function and structure was reevaluated after 1.5, 3, and 10 months. In a subset of animals, the nerves were again severed and implanted into the other vessel. Twelve of 18 nerves implanted into arteries regained typical neurophysiological activity, but none of those implanted into veins. Two times even baroreflexes were elicited through the newly built nerve endings. The structure of the nerve endings implanted into arteries resembled baroreceptors, whereas no fiber growth was detected in veins. Morphometrically, the fiber number and diameter increased over the observed time period after implantation into arteries. Nerves implanted into veins, transected after 3 months, and then implanted into arteries also regained neurophysiological activity. Again, they rebuilt baroreceptors and significantly increased their fiber number and diameter. In conclusion, when severed baroafferents are implanted into arteries, they regenerate new baroreceptors and restore the normal myelination and fiber size of the nerve over time, whereas veins seem to inhibit nerve fiber sprouting and regeneration of severed fiber