Thorsten Brand's research while affiliated with Friedrich-Alexander-University of Erlangen-Nürnberg and other places

... Figure 22 shows the expected instrument throughput performance as a function of count rate/flux for the different observation types specified in the X-IFU count rate requirements, and relying on the defocusing capability of the Athena telescope (see Fig. 22 to visualise how the point spread function of the optics varies with energy at an out-of-focus distance of 35 mm, [77]). These results were obtained using detailed End-to-End simulations performed in the SIXTE environment [79], taking into account all the above-mentioned processes [78]. As can be seen, a significant margin exists with respect to all performance requirements, and almost all goals are met. ...

... We note here that the eROSITA X-ray detection algorithm for extended sources does not correspond to a pure flux limit, as we discuss in section 3.4 below (see alsoClerc et al. 2018;Seppi et al. 2022).MNRAS 000, 1-15(2015) ...

... In superconductors research series, ILS method was widely applied [3][4][5][6][39][40][41][42][43][44][45][46][47][48][49]. Genetic Algorithms (GA) method was applied on Hg-Cuprates HTSC class [3][4][5]48,49] with acceptable results. ...

... However, these absorption models do not allow for complex geometries, which are often needed to reproduce all the complex features observed in the X-ray spectra of astrophysical sources. The advent of the high spectral resolution instruments on board XRISM (Resolve, XRISM Science Team 2020) and Athena (X-IFU, Barret et al. 2016) will require improved models, which include all the relevant physical processes, taking into account reprocessed radiation and absorbed emission, and consider realistic geometries of the material around X-ray sources. In this work we report on the implementation of dust absorption and scattering in the raytracing platform REFLEX 4 (Paltani & Ricci 2017), which allows us to create self-consistent physical models of the environment of X-ray sources including dusty gas. ...

... Accurate thermalisation of large format and high-density arrays of microcalorimeters plays a crucial role in the minimisation of the thermal crosstalk between nearby pixels [12]. Facing this problem turns out to be crucial in order to meet the energy resolution requirements for the specific project [13]. For instance, Athena has allocated 0.2 eV inside the instrument's energy resolution budget for the impact of the thermal crosstalk. ...

... The strength of this numerical time-domain model is that, beside predicting the steady state of the TES, it can also be used to simulate the TES response to the incoming photons in the non-linear and large signal regime. As a matter of fact, this TES simulator will become part of the end-to-end (e2e) simulator of the X-IFU on Athena [67,68]. In Figure 5, we give an example of the simulation of high normal resistance TES microcalorimeters developed at NASA-GSFC for the Athena/X-IFU and characterized at SRON under MHz bias. ...

... In this section, we review the count rate capability of X-IFU, starting with the list of requirements to be met (see the last column, Table 6). One of the most emblematic count rate requirements for X-IFU is the one related to mCrab intensity sources observed out-of-focus requiring a throughput of 80% for 2.5 eV spectral resolution, and is driven by the capability to observe bright gamma-ray burst afterglows to probe the Warm Hot Intergalactic Medium [75,76]. Another one is certainly the one related to the capability of observing very bright X-ray sources (1 Crab intensity level) with X-IFU, thanks to the optics defocussing and the addition of thick filters along the light path. ...

... Rights reserved. [50][51][52][53]. The accurate energy of the photon in keV will then be obtained on-ground accounting for the gain scale (and other corrections). ...

... One of the two instruments in its focal plane is the Wide Field Imager (WFI). It will be comprised of four 512 × 512 monolithic DePFET matrices ( Figure 4B) with 130 × 130 μm 2 pixel size [9,10]. Addressing and readout are done by the next generation of Switcher (SwitcherA) and readout ASIC (Veritas-2) [11]. ...

... DEPFETs are planned to be used in the large area detector system (Ott et al. 2016). ...