Lynx is a concept under study for prioritization in the 2020 Astrophysics Decadal Survey. Providing orders of magnitude increase in sensitivity over Chandra, Lynx will examine the first black holes and their galaxies, map the large-scale structure and galactic halos, and shed new light on the environments of young stars and their planetary systems. In order to meet the Lynx science goals, the telescope consists of a high-angular resolution optical assembly complemented by an instrument suite that may include a High Definition X-ray Imager, X-ray Microcalorimeter and an X-ray Grating Spectrometer. The telescope is integrated onto the spacecraft to form a comprehensive observatory concept. Progress on the formulation of the Lynx telescope and observatory configuration is reported in this paper.

NASA's Chandra X-ray Observatory continues to provide an unparalleled means for exploring the high-energy universe. With its half-arcsecond angular resolution, Chandra studies have deepened our understanding of galaxy clusters, active galactic nuclei, galaxies, supernova remnants, neutron stars, black holes, and solar system objects. As we look beyond Chandra, it is clear that comparable or even better angular resolution with greatly increased photon throughput is essential to address ever more demanding science questions-such as the formation and growth of black hole seeds at very high redshifts; the emergence of the first galaxy groups; and details of feedback over a large range of scales from galaxies to galaxy clusters. Recently, we initiated a concept study for such a mission, dubbed X-ray Surveyor. The X-ray Surveyor strawman payload is comprised of a high-resolution mirror assembly and an instrument set, which may include an X-ray microcalorimeter, a high-definition imager, and a dispersive grating spectrometer and its readout. The mirror assembly will consist of highly nested, thin, grazing-incidence mirrors, for which a number of technical approaches are currently under development-including adjustable X-ray optics, differential deposition, and new polishing techniques applied to a variety of substrates. This study benefits from previous studies of large missions carried out over the past two decades and, in most areas, points to mission requirements no more stringent than those of Chandra.

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Modular, executable, decision-centric templates have been used as a means to model design processes computationally. The use of decision templates has been limited so far to decision making by a single stakeholder. Templates for multiple stakeholders, making concurrent decisions regarding the design of a product have not been developed. In this paper, we extend the current template-based approach using Game-Based Design, which is a method incorporating game theoretic protocols in engineering design and has been proposed as a means to solve design decision problems for multiple stakeholders. The interactions between multiple decision makers are modeled using cooperative, non-cooperative, and leader follower protocols. The proposed approach facilitates collaboration between two stakeholders by organizing design process information using decision-centric templates. The proposed approach facilitates computational modeling of designer interactions in a distributed environment by capturing the dynamics of collaborative decision making. It is demonstrated with respect to facilitating the design and prototype manufacture of a separation channel for a microscale gas chromatography system. I. Frame of Reference A. Collaborative Design in a Distributed Environment The focus in this paper is on facilitating the design of systems, complex enough to warrant resolution by multiple interacting domain experts. Although design problems can often be addressed adequately by a single designer there are many instances when the expertise of more than a single decision-maker is required, due to limited domain knowledge, assignment of responsibility, value chain configuration, etc. This necessitates effective collaboration in spite of distribution and tradeoff among conflicting objectives. In order to address the needs of collaborative design a consistent means of modeling a) stakeholder activities and b) their interactions is required. Decision templates proposed by Panchal and co-authors 4 comprise such a means and allow for the consistent (i.e., standardized) formulation of a designer's decision. A primary benefit in this regard is that the information required for making decisions and the result of these decisions can be captured in a modular, reusable, computationally executable manner. This, however, does not address the collaborative design scenario in a distributed environment. The requirements for a template-based approach addressing collaborative design include facilitatinga) Modeling of multidisciplinary , multi-objective design involving multiple decisions in a consistent, domain independent manner b) Modeling of different types of interactions between decision makers such as sequential, decentralized, and centralized decision-making c) Composability and reconfigurability of the design process d) Simulation-based design in a distributed environment e) Information capture in a reusable, adaptable, and extensible form Complex design processes generally involve designers from multiple domains making decisions about the products ...

LOFT-P is a mission concept for a NASA Astrophysics Probe-Class (<$1B) X-ray timing mission, based on the LOFT M-class concept originally proposed to ESAs M3 and M4 calls. LOFT-P requires very large collecting area, high time resolution, good spectral resolution, broad-band spectral coverage (2-30 keV), highly flexible scheduling, and an ability to detect and respond promptly to time-critical targets of opportunity. It addresses science questions such as: What is the equation of state of ultra dense matter? What are the effects of strong gravity on matter spiraling into black holes? It would be optimized for sub-millisecond timing of bright Galactic X-ray sources including X-ray bursters, black hole binaries, and magnetars to study phenomena at the natural timescales of neutron star surfaces and black hole event horizons and to measure mass and spin of black holes. These measurements are synergistic to imaging and high-resolution spectroscopy instruments, addressing much smaller distance scales than are possible without very long baseline X-ray interferometry, and using complementary techniques to address the geometry and dynamics of emission regions. LOFT-P would have an effective area of >6 m 2 , > 10× that of the highly successful Rossi X-ray Timing Explorer (RXTE). A sky monitor (2-50 keV) acts as a trigger for pointed observations, providing high duty cycle, high time resolution monitoring of the X-ray sky with ∼20 times the sensitivity of the RXTE All-Sky Monitor, enabling multi-wavelength and multimessenger studies. A probe-class mission concept would employ lightweight collimator technology and large-area solid-state detectors, segmented into pixels or strips, technologies which have been recently greatly advanced during the ESA M3 Phase A study of LOFT. Given the large community interested in LOFT (>800 supporters * , the scientific productivity of this mission is expected to be very high, similar to or greater than RXTE (∼ 2000 refereed publications). We describe the results of a study, recently completed by the MSFC Advanced Concepts Office, that demonstrates that such a mission is feasible within a NASA probe-class mission budget.