Gravitational wave recoil in Robinson-Trautman spacetimes

We consider the gravitational recoil due to nonreflection-symmetric gravitational wave emission in the context of axisymmetric Robinson-Trautman spacetimes. We show that regular initial data evolve generically into a final configuration corresponding to a Schwarzschild black hole moving with constant speed. For the case of (reflection-)symmetric initial configurations, the mass of the remnant black hole and the total energy radiated away are completely determined by the initial data, allowing us to obtain analytical expressions for some recent numerical results that have appeared in the literature. Moreover, by using the Galerkin spectral method to analyze the nonlinear regime of the Robinson-Trautman equations, we show that the recoil velocity can be estimated with good accuracy from some asymmetry measures (namely the first odd moments) of the initial data. The extension for the nonaxisymmetric case and the implications of our results for realistic situations involving head-on collision of two black holes are also discussed.

Cavity-Controlled Collective Scattering at the Recoil Limit

We study collective scattering with Bose-Einstein condensates interacting with a high-finesse ring cavity. The condensate scatters the light of a transverse pump beam superradiantly into modes which, in contrast to previous experiments, are not determined by the geometrical shape of the condensate, but specified by a resonant cavity mode. Moreover, since the recoil-shifted frequency of the scattered light depends on the initial momentum of the scattered fraction of the condensate, we show that it is possible to employ the good resolution of the cavity as a filter selecting particular quantized momentum states.

Corrosion resistance enhancement of SAE 1020 steel after Chromium implantation by nitrogen ion recoil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A novel method for modeling the recoil in W boson events at hadron colliders

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Measurement of the proton recoil spectrum in neutron beta decay with the spectrometer aSPECT : study of systematic effects

Precision measurements of observables in neutron beta decay address important open questions of particle physics and cosmology. In this thesis, a measurement of the proton recoil spectrum with the spectrometer aSPECT is described. From this spectrum the antineutrino-electron angular correlation coefficient a can be derived. In our first beam time at the FRM II in Munich, background instabilities prevented us from presenting a new value for a. In the latest beam time at the ILL in Grenoble, the background has been reduced sufficiently. As a result of the data analysis, we identified and fixed a problem in the detector electronics which caused a significant systematic error. The aim of the latest beam time was a new value for a with an error well below the present literature value of 4%. A statistical accuracy of about 1.4% was reached, but we could only set upper limits on the correction of the problem in the detector electronics, too high to determine a meaningful result. This thesis focused on the investigation of different systematic effects. With the knowledge of the systematics gained in this thesis, we are able to improve aSPECT to perform a 1% measurement of a in a further beam time.

Comparison of in vivo acute stent recoil between the bioresorbable everolimus-eluting coronary scaffolds (revision 1.0 and 1.1) and the metallic everolimus-eluting stent

The ABSORB cohort A trial using the bioresorbable everolimus-eluting scaffold (BVS revision 1.0, Abbott Vascular) demonstrated a slightly higher acute recoil with BVS than with metallic stents. To reinforce the mechanical strength of the scaffold, the new BVS scaffold (revision 1.1) with modified strut design was developed and tested in the ABSORB cohort B trial. This study sought to evaluate and compare the in vivo acute scaffold recoil of the BVS revision 1.0 in ABSORB cohort A and the BVS revision 1.1 in ABSORB cohort B with the historical recoil of the XIENCE V® everolimus-eluting metal stent (EES, SPIRIT I and II).

The recoil transfer chamber - An interface to connect the physical preseparator TASCA with chemistry and counting setups

Performing experiments with transactinide elements demands highly sensitive detection methods due to the extremely low production rates (one-atom-at-a-time conditions). Preseparation with a physical recoil separator is a powerful method to significantly reduce the background in experiments with sufficiently long-lived isotopes (t1/2≥0.5 s). In the last years, the new gas-filled TransActinide Separator and Chemistry Apparatus (TASCA) was installed and successfully commissioned at GSI. Here, we report on the design and performance of a Recoil Transfer Chamber (RTC) for TASCA—an interface to connect various chemistry and counting setups with the separator. Nuclear reaction products recoiling out of the target are separated according to their magnetic rigidity within TASCA, and the wanted products are guided to the focal plane of TASCA. In the focal plane, they pass a thin Mylar window that separates the ∼1 mbar atmosphere in TASCA from the RTC kept at ∼1 bar. The ions are stopped in the RTC and transported by a continuous gas flow from the RTC to the ancillary setup. In this paper, we report on measurements of the transportation yields under various conditions and on the first chemistry experiments at TASCA—an electrochemistry experiment with osmium and an ion exchange experiment with the transactinide element rutherfordium.

Cosmogenic production rates and recoil loss effects in micrometeorites and interplanetary dust particles

We present a purely physical model to determine cosmogenic production rates for noble gases and radionuclides in micrometeorites (MMs) and interplanetary dust particles (IDPs) by solar cosmic-rays (SCR) and galactic cosmic-rays (GCR) fully considering recoil loss effects. Our model is based on various nuclear model codes to calculate recoil cross sections, recoil ranges, and finally the percentages of the cosmogenic nuclides that are lost as a function of grain size, chemical composition of the grain, and the spectral distribution of the projectiles. The main advantage of our new model compared with earlier approaches is that we consider the entire SCR particle spectrum up to 240 MeV and not only single energy points. Recoil losses for GCR-produced nuclides are assumed to be equal to recoil losses for SCR-produced nuclides. Combining the model predictions with Poynting-Robertson orbital lifetimes, we calculate cosmic-ray exposure ages for recently studied MMs, cosmic spherules, and IDPs. The ages for MMs and the cosmic-spherule are in the range <2.2–233 Ma, which corresponds, according to the Poynting-Robertson drag, to orbital distances in the range 4.0–34 AU. For two IDPs, we determine exposure ages of longer than 900 Ma, which corresponds to orbital distances larger than 150 AU. The orbital distance in the range 4–6 AU for one MM and the cosmic spherule indicate an origin either in the asteroid belt or release from comets coming either from the Kuiper Belt or the Oort Cloud. Three of the studied MMs have orbital distances in the range 23–34 AU, clearly indicating a cometary origin, either from short-period comets from the Kuiper Belt or from the Oort Cloud. The two IDPs have orbital distances of more than 150 AU, indicating an origin from Oort Cloud comets.