23 research outputs found
Mexico-UK Sub-millimeter Camera for AsTronomy
MUSCAT is a large format mm-wave camera scheduled for installation on the
Large Millimeter Telescope Alfonso Serrano (LMT) in 2018. The MUSCAT focal
plane is based on an array of horn coupled lumped-element kinetic inductance
detectors optimised for coupling to the 1.1mm atmospheric window. The detectors
are fed with fully baffled reflective optics to minimize stray-light
contamination. This combination will enable background-limited performance at
1.1 mm across the full 4 arcminute field-of-view of the LMT. The easily
accessible focal plane will be cooled to 100 mK with a new closed cycle
miniature dilution refrigerator that permits fully continuous operation. The
MUSCAT instrument will demonstrate the science capabilities of the LMT through
two relatively short science programmes to provide high resolution follow-up
surveys of Galactic and extra-galactic sources previously observed with the
Herschel space observatory, after the initial observing campaigns. In this
paper, we will provide an overview of the overall instrument design as well as
an update on progress and scheduled installation on the LMT.Comment: Accepted for publication in the Journal of Low Temperature Detector
MUSCAT: The Mexico-UK Sub-Millimetre Camera for AsTronomy
The Mexico-UK Sub-millimetre Camera for AsTronomy (MUSCAT) is a large-format,
millimetre-wave camera consisting of 1,500 background-limited lumped-element
kinetic inductance detectors (LEKIDs) scheduled for deployment on the Large
Millimeter Telescope (Volc\'an Sierra Negra, Mexico) in 2018. MUSCAT is
designed for observing at 1.1 mm and will utilise the full 40' field of view of
the LMTs upgraded 50-m primary mirror. In its primary role, MUSCAT is designed
for high-resolution follow-up surveys of both galactic and extra-galactic
sub-mm sources identified by Herschel. MUSCAT is also designed to be a
technology demonstrator that will provide the first on-sky demonstrations of
novel design concepts such as horn-coupled LEKID arrays and closed continuous
cycle miniature dilution refrigeration.
Here we describe some of the key design elements of the MUSCAT instrument
such as the novel use of continuous sorption refrigerators and a miniature
dilutor for continuous 100-mK cooling of the focal plane, broadband optical
coupling to Aluminium LEKID arrays using waveguide chokes and anti-reflection
coating materials as well as with the general mechanical and optical design of
MUSCAT. We explain how MUSCAT is designed to be simple to upgrade and the
possibilities for changing the focal plane unit that allows MUSCAT to act as a
demonstrator for other novel technologies such as multi-chroic polarisation
sensitive pixels and on-chip spectrometry in the future. Finally, we will
report on the current status of MUSCAT's commissioning.Comment: Presented at SPIE Astronomical Telescopes + Instrumentation, 2018,
Austin, Texas, United State
Pre-deployment verification and predicted mapping speed of MUSCAT
The Mexico-UK Submillimetre Camera for AsTronomy (MUSCAT) is a 1.1 mm receiver consisting of 1,500 lumped-element kinetic inductance detectors (LEKIDs) for the Large Millimeter Telescope (LMT; Volcán Sierra Negra in Puebla, México). MUSCAT utilises the maximum field of view of the LMT's upgraded 50-metre primary mirror and is the first México-UK collaboration to deploy a millimetre/sub-mm receiver on the Large Millimeter Telescope. Using a simplistic simulator, we estimate a predicted mapping speed for MUSCAT by combining the measured performance of MUSCAT with the observed sky conditions at the LMT. We compare this to a previously calculated bolometric-model mapping speed and find that our mapping speed is in good agreement when this is scaled by a previously reported empirical factor. Through this simulation we show that signal contamination due to sky fluctuations can be effectively removed through the use of principle component analysis. We also give an overvie
Design and characterization of the MUSCAT detectors
MUSCAT is a second-generation continuum camera for the Large Millimeter Telescope (LMT) 'Alfonso Serrano', to observe at the 1.1 mm atmospheric window. The camera has 1500 background-limited, horn-coupled lumped- element kinetic inductance detectors (LEKIDs) split across six arrays operating at 130-mK. The detector design for MUSCAT is based on a large-volume, double-meander geometry used as the inductive and two-polarization absorbing section of the LEKID resonator. In this paper we present the optical coupling of the meander to a choked waveguide output, the microwave design of the LEKID architecture, the device fabrication process and results demonstrating the detector sensitivity under a range of optical loads. Also presented are the performance of an aluminum absorbing layer used to minimize the optical cross-talk between detectors
MUSCAT focal plane verification
The Mexico-UK Submillimetre Camera for Astronomy (MUSCAT) is the second-generation large-format continuum camera operating in the 1.1 mm band to be installed on the 50-m diameter Large Millimeter Telescope (LMT) in Mexico. The focal plane of the instrument is made up of 1458 horn coupled lumped-element kinetic inductance detectors (LEKID) divided equally into six channels deposited on three silicon wafers. Here we present the preliminary results of the complete characterisation in the laboratory of the MUSCAT focal plane. Through the instrument's readout system, we perform frequency sweeps of the array to identify the resonance frequencies, and continuous timestream acquisitions to measure and characterise the intrinsic noise and 1/f knee of the detectors. Subsequently, with a re-imaging lens and a blackbody point source, the beams of every detector are mapped, obtaining a mean FWHM size of ~3.27 mm, close to the expected 3.1 mm. Then, by varying the intensity of a beam filling blackbody source, we measure the responsivity and noise power spectral density (PSD) for each detector under an optical load of 300 K, obtaining the noise equivalent power (NEP), with which we verify that the majority of the detectors are photon noise limited. Finally, using a Fourier Transform Spectrometer (FTS), we measure the spectral response of the instrument, which indicate a bandwidth of 1.0-1.2 mm centred on 1.1 mm, as expected
El rol del Instituto Mexicano del Petróleo (IMP) en el desarrollo de la industria petrolera en México al 2015.
Tesis (Maestría en geociencias y administración de los recursos naturales), Instituto Politécnico Nacional, SEPI, ESIA, 2017, 1 archivo PDF, (85 páginas).tesis.ipn.m
Embedded system upgrade based on Raspberry Pi computer for a 23/31 GHz dual-channel water vapor radiometer
We present the refurbishment of a 23.8/31.5 GHz tipping radiometer (WVR-III) to characterize atmospheric opacity for
astronomical sites. The mid-life upgrade will bring new life to the 20-year-old WVR-III with most control functions now
embedded on a Raspberry PI 3B+ (RPi-3B+). The radiometer will be installed alongside the 225 GHz radiometer at the
Large Millimeter Telescope site in Mexico and in 2021 it will be taken to the Hartebeesthoek Radio Astronomy
Observatory in South Africa. Later, it will be deployed to Mt Gamsberg, Namibia to perform PWV site surveying for
potential future radio astronomy telescopes. This paper describes the new control and data acquisition sub-systems that
are controlled by the RPi-3B+.The Consejo Nacional de Ciencia y Tecnología (CONACyT-Mexico), the National Research Foundation (South Africa), the Universidad Nacional Autónoma de México (UNAM).https://www.spiedigitallibrary.org/conference-proceedings-of-spieam2021Electrical, Electronic and Computer Engineerin
The optical design and performance of TolTEC: a millimeter-wave imaging polarimeter
TolTEC is an imaging polarimeter that will be mounted on the 50m diameter Large Millimeter Telescope (LMT) in Mexico. This camera simultaneously images the focal plane at three wavebands centered at 1.1, 1.4, and 2.0mm. TolTEC combines polarization-sensitive Kinetic Inductance Detectors (KIDs) with the LMT to produce 5-10 arcmin resolution maps of the sky in both total intensity and polarization. The light from the telescope is coupled to the TolTEC instrument using three room temperature mirrors. Before entering the cryostat, the light passes through a rapid-spinning achromatic half-wave plate, and once inside it passes through a 1 K Lyot stop that controls the telescope illumination. Inside the cryostat, a series of aluminum mirrors, silicon lenses, and dichroic filters split the light into three wavelength bands and direct each band to a different detector array. We will describe the design, and performance of the optics before installation at the telescope