Strukturbildung und schwacher Linseneffekt in kosmologischen Modellen mit dynamischer Dunkler Energie
Final Report Abstract
Summarising, the following work was carried out during the duration of the project reported: 1. Early dark-energy models were selected which are in agreement with different classes of observational constraints; 2. Numerical realisations of these models were run at the Stuttgart computer centre with parameters suitable for later weak-lensing analysis; 3. Preliminary analyses of these simulations seem to confirm analytic predictions on early dark-energy models; 4. A ray-tracing code was newly developed and successfully tested on an existing, gas-dynamical simulation provided to us by the collaborating group of Prof. Moscardini in Bologna; 5. Using a catalog of dark-matter halos in the three-dimensional simulation, the performance of a filter optimised for detecting the weak-lensing signature of halos could be calibrated and quantified in detail; 6. Taking advantage of the gas included in the simulation, halo searches based on linear filtering techniques applied to gravitational-lensing, X-ray, and thermal SZ data could be compared and cross-calibrated. The project suffered from major delays caused by (1) the necessity to newly implement the ray-tracing code, (2) the application for computation time at the Stuttgart computer centre and the adaptation of the Gadget code to the software environment available there, and (3) the search for dark-matter halos in the unwieldily organised simulation data. Yet, Mr. Pace could complete his Ph.D. work within the duration of the project, which became possible because part of the work could be carried out on the gas-dynamical data provided by our partner group in Bologna. The numerical tools developed, the simulation data produced and the experience gained with them form an excellent basis for continuing the planned research aiming at testing early dark-energy models. Mr. Pace has achieved substantial scientific results within the project reported which allow for the first time to quantify in detail the expectations on the efficiency and reliability of searches for massive, non-linear structures with techniques based on gravitational lensing and the observable signatures of hot gas.
Publications
- Meneghetti, M., Argazzi, R., Pace, F., Moscardini, L., Dolag, K., Bartelmann, M., Li, G., Oguri, M. "Arc sensitivity to cluster ellipticity, asymmetries, and substructures". Astron. Astrophys. 461 (2007) 25
- Pace, F., Maturi, M., Meneghetti, M., Bartelmann, M., Moscardini, L, Dolag, K. "Testing the reliability of weak Iensing cluster detections". Astron. Astrophys. 471 (2007) 731.
