The Magdalena Ridge Observatory Interferometer has been designed to be a 10 × 1.4 m aperture long-baseline optical/near-infrared interferometer in an equilateral "Y" configuration, and is being deployed west of Socorro, NM on the Magdalena Ridge. Unfortunately, first light for the facility has been delayed due to the current difficult funding regime, but during the past two years we have made substantial progress on many of the key subsystems for the array. The design of all these subsystems is largely complete, and laboratory assembly and testing, and the installation and site acceptance testing of key components on the Ridge are now underway. This paper serves as an overview and update on the facility's present status and changes since 2012, and the plans for future activities and eventual operations of the facilities.
The loop is closed on ICONN, the Magdalena Ridge Observatory Interferometer fringe tracker. Results from laboratory experiments demonstrating ICONN's ability to track realistic, atmospheric-like path difference perturbations in real-time are shown. Characterizing and understanding the behavior and limits of ICONN in a controlled environment are key for reaching the goals of the MROI. The limiting factors in the experiments were found to be the light delivery system and temporary path length correction mechanism; not the on-sky components of ICONN. ICONN was capable of tracking fringes with a coherence loss below 5%; this will only improve in its final deployment.
The characterization of ICoNN, the Magdalena Ridge Observatory Interferometer's fringe tracker, through labor tory simulations is presented. The performance limits of an interferometer are set by its ability to keep the optical path difference between combination partners minimized. This is the job of the fringe tracker. Understanding the behavior and limits of the fringe tracker in a controlled environment is key to maximize the science output. This is being done with laboratory simulations of on-sky fringe tracking, termed the closed-loop fringe experi ment. The closed-loop fringe experiment includes synthesizing a white light source and atmospheric piston with estimation of the tracking error being fed back to mock delay lines in real-time. We report here on the progress of the closed-loop fringe experiment detailing its design, layout, controls and software.
Most subsystems of the Magdalena Ridge Observatory Interferometer (MROI) have progressed towards
final mechanical design, construction and testing since the last SPIE meeting in San Diego - CA. The first
1.4-meter telescope has successfully passed factory acceptance test, and construction of telescopes #2 and
#3 has started. The beam relay system has been prototyped on site, and full construction is awaiting
funding. A complete 100-meter length delay line system, which includes its laser metrology unit, has been
installed and tested on site, and the first delay line trolley has successfully passed factory acceptance
testing. A fully operational fringe tracker is integrated with a prototyped version of the automated
alignment system for a closed looping fringe tracking experiment. In this paper, we present details of the
final mechanical and opto-mechanical design for these MROI subsystems and report their status on
fabrication, assembly, integration and testing.
The Magdalena Ridge Observatory Interferometer has been designed to be a 10 x 1.4 m aperture long-baseline
optical/near-infrared interferometer in an equilateral "Y" configuration, and is being deployed west of Socorro, NM on
the Magdalena Ridge. Unfortunately, first light for the facility has been delayed due to the current difficult funding
regime, but during the past two years we have made substantial progress on many of the key subsystems for the array.
The design of all these subsystems is largely complete, and laboratory assembly and testing, and the installation of many of its components on the Ridge are now underway. This paper serves as an overview and update on the facility's present status, and the plans for future funding and eventual operations of the facilities.
The MROI fringe tracking beam combiner will be the first fringe instrument for the interferometer. It was designed to
utilize the array geometry and maximize sensitivity to drive the interferometer for faint source imaging. Two primary
concerns have driven the design philosophy: 1) maintaining high throughput and visibilities in broadband polarized light,
and 2) mechanical stability. The first concern was addressed through tight fabrication tolerances of the combiner substrates, and custom coatings. In order to optimize mechanical stability, a unique modular design approach was taken that minimizes the number of internal adjustments. This paper reports initial laboratory fringe and stability measurements.
The Magdalena Ridge Observatory Interferometer is a 10 x 1.4 meter aperture long baseline optical and near-infrared
interferometer being built at 3,200 meters altitude on Magdalena Ridge, west of Socorro, NM. The interferometer layout
is an equilateral "Y" configuration to complement our key science mission, which is centered on imaging faint and
complex astrophysical targets. This paper serves as an overview and update on the status of the observatory and our
progress towards first light and first fringes in 2012.
Here is presented the current outline and progress of MROI's automated alignment system design. Depending on the
location of each of MROI's unit telescopes (UT), light can travel distances ranging from 460 to 660 meters via
several reflections that redirect the beam's path through the beam relay system (BRS), delay line system (DLS),
beam compressing telescope (BCR), switchyards and finally to the beam combiners (BC). All of these sub-systems
comprise three major optical axes of the MROI which must be coaligned on a nightly basis by the AAS. The AAS
consists of four subsystems: the primary fiducial-for beam injection, the UT tilt and shear measurement
components (TASM), the BC TASM components, and the secondary fiducial-for quick alignment checks. All of
these subsystems contribute to the unique design of the AAS which will allow for simultaneous measurements from
the visible to the near-IR wavelengths, full automation, the capability to perform optical path difference (OPD)
alignment and spectral calibration, making it cost effective and saving on realty in the beam combining area (BCA).
The AAS is nearing completion and assembly of the various subsystems is expected to commence soon. The latest
results on all of the following are reviewed here.
KEYWORDS: Mirrors, Telescopes, Mechanical engineering, Fourier transforms, Optical benches, Interferometers, Spectrographs, Aluminum, Beam splitters, Simulation of CCA and DLA aggregates
We report on the mechanical design currently performed at the Magdalena Ridge Observatory
Interferometer (MROI) and how the construction, assembly, integration and verification are planned
towards commissioning. Novel features were added to the mechanical design, and high level of automation
and reliability are being devised, which allows the number of reflections to be kept down to a minimum
possible. This includes unit telescope and associated enclosure and transporter, fast tip-tilt system, beam
relay system, delay line system, beam compressor, automated alignment system, beam turning mirror,
switchyard, fringe tracker and vacuum system.
The Magdalena Ridge Observatory Interferometer (MROI) will be a reconfigurable (7.5-345 meter baselines) 10
element optical/near-infrared imaging interferometer. Depending on the location of each unit telescope (UT), light
can travel distances ranging from 460 to 660 meters via several reflections that redirect the beam's path through the
beam relay trains, delay lines (DL), beam reducing telescope (BCR), switchyards and finally to the beam combiners
(BC). All of these sub-systems comprise three major optical axes of the MROI to be coaligned on a nightly basis by
the alignment system. One major obstacle in designing the automated alignment system (AAS) is the required
simultaneous measurements from the visible through near-IR wavelengths. Another difficulty is making it fully
automated, which has not been accomplished at other optical/near-IR interferometers. The conceptual design of this
system has been completed and is currently in its preliminary design phase. Prototyping has also commenced with
designs of some hardware near completion. Here is presented the current outline and progress of MROI's automated
alignment system design and some results of the prototyping.
The Magdalena Ridge Observatory Interferometer is a 10-element 1.4 meter aperture optical and near-infrared
interferometer being built at 3,200 meters altitude on Magdalena Ridge, west of Socorro, NM. The
interferometer layout is an equilateral "Y" configuration to complement our key science mission, which is
centered around imaging faint and complex astrophysical targets. This paper serves as an overview and
update on the status of the observatory and our progress towards first light and first fringes in the next few
years.
The Magdalena Ridge Observatory Interferometer (MROI) is a ten element optical and near-infrared imaging interferometer being built in the Magdalena mountains west of Socorro, NM at an altitude of 3230 m. The interferometer is being designed and built by a collaboration which includes the New Mexico Institute of Mining and Technology (NMT) as the prime contractor and center for the technical team, and the University of Cambridge, Physics Department at the Cavendish Laboratory, which participates in the design and executes work packages under contract with NMT. This manuscript serves as a status update on MROI, and will present progress and milestones toward the observatory's first fringes in 2008.
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