4 research outputs found
Development of the Arizona Robotic Telescope Network
The Arizona Robotic Telescope Network (ARTN) project is a long term effort to
develop a system of telescopes to carry out a flexible program of PI observing,
survey projects, and time domain astrophysics including monitoring, rapid
response, and transient/target-of-opportunity followup. Steward Observatory
operates and shares in several 1-3m class telescopes with quality sites and
instrumentation, largely operated in classical modes. Science programs suited
to these telescopes are limited by scheduling flexibility and people-power of
available observers. Our goal is to adapt these facilities for multiple
co-existing queued programs, interrupt capability, remote/robotic operation,
and delivery of reduced data. In the long term, planning for the LSST era, we
envision an automated system coordinating across multiple telescopes and sites,
where alerts can trigger followup, classification, and triggering of further
observations if required, such as followup imaging that can trigger
spectroscopy. We are updating telescope control systems and software to
implement this system in stages, beginning with the Kuiper 61'' and Vatican
Observatory 1.8-m telescopes. The Kuiper 61'' and its Mont4K camera can now be
controlled and queue-scheduled by the RTS2 observatory control software, and
operated from a remote room at Steward. We discuss science and technical
requirements for ARTN, and some of the challenges in adapting heterogenous
legacy facilities, scheduling, data pipelines, and maintaining capabilities for
a diverse user base.Comment: Proceedings of SPIE Astronomical Telescopes & Instrumentation 2018,
Observatory Operations: Strategies, Processes, and Systems VI
Search for Outer Massive Bodies around Transiting Planetary Systems: Candidates of Faint Stellar Companions around HAT-P-7
We present results of direct imaging observations for HAT-P-7 taken with the
Subaru HiCIAO and the Calar Alto AstraLux. Since the close-in transiting planet
HAT-P-7b was reported to have a highly tilted orbit, massive bodies such as
giant planets, brown dwarfs, or a binary star are expected to exist in the
outer region of this system. We show that there are indeed two candidates for
distant faint stellar companions around HAT-P-7. We discuss possible roles
played by such companions on the orbital evolution of HAT-P-7b. We conclude
that as there is a third body in the system as reported by Winn et al. (2009,
ApJL, 763, L99), the Kozai migration is less likely while planet-planet
scattering is possible.Comment: 8 pages, 3 figures, 2 tables, PASJ in pres
A Universal, Dynamically Adaptable and Programmable Network Router for Parallel Computers
Existing message-passing parallel computers employ routers designed for a specific interconnection network and deal with fixed data channel width. There are disadvantages to this approach, because the system design and development times are significant and these routers do not permit run time network reconfiguration. Changes in the topology of the network may be required for better performance or fault-tolerance. In this paper, we introduce a class of highperformance universal (statically and dynamically adaptable) programmable routers (UPRs) for message-passing parallel computers. The universality of these routers is based on their capability to adapt at run and/or static times according to the characteristics of the systems and/or applications. More specifically, the number of bidirectional data channels, the channel size and the I/O port mappings (for the implementation of a particular topology) can change dynamically and statically. Our research focuses on system-level specification issues of the UPRs, their VLSI design and their simulation to estimate their performance. Our simulation of data transfers via UPR routers employs VHDL code in the Mentor Graphics environment.The results show that the performance of the routers depends mostly on their current configuration. Details of the simulation and synthesis are presented