1,754 research outputs found
SAMBA: Superconducting antenna-coupled, multi-frequency, bolometric array
We present a design for a multipixel, multiband (100 GHz, 200 GHz and 400 GHz) submillimeter instrument: SAMBA (Superconducting Antenna-coupled, Multi-frequency, Bolometric Array). SAMBA uses slot antenna coupled bolometers and microstrip filters. The concept allows for a much more compact, multiband imager compared to a comparable feedhorn-coupled bolometric system. SAMBA incorporates an array of slot antennas, superconducting transmission lines, a wide band multiplexer and superconducting transition edge bolometers. The transition-edge film measures the millimeter-wave power deposited in the resistor that terminates the transmission line
Integrated Focal Plane Arrays for Millimeter-wave Astronomy
We are developing focal plane arrays of bolometric detectors for sub-millimeter and millimeter-wave astrophysics. We propose a flexible array architecture using arrays of slot antennae coupled via low-loss superconducting Nb transmission line to microstrip filters and antenna-coupled bolometers. By combining imaging and filtering functions with transmission line, we are able to realize unique structures such as a multi-band polarimeter and a planar, dispersive spectrometer. Micro-strip bolometers have significantly smaller active volume than
standard detectors with extended absorbers, and can realize higher sensitivity and speed of response. The integrated array has natural immunity to stray radiation or spectral leaks, and minimizes the suspended mass operating at 0.1 - 0.3 K. We also discuss future space-borne spectroscopy and polarimetry applications
Morbidity and mortality in adults with congenital heart defects in the third and fourth life decade
Objectives: The population of adults with congenital heart defects (ACHD) is continuously growing. Data on morbidity and mortality of ACHD are limited. This longitudinal observational study examined a group of ACHD with surgically corrected or palliated congenital heart defects (CHD) during a 15-year period. Methods: ACHD that had participated in the initial study were invited for a follow-up examination. Mortality and hospitalization data were compared with a healthy control group. Results: From 05/2017 to 04/2019 a total of 249/364 (68%) ACHD participated in the follow-up study: 21% had mild, 60% moderate and 19% severe CHD. During the observational period, 290 health incidents occurred (cardiac catheterization 37%, cardiovascular surgery 27%, electrophysiological study/ablation 20%, catheter interventional treatment 14%, non-cardiac surgery 3%). Events were more frequent in ACHD with moderate (53%) and severe (87%) compared to those with mild CHD (p \u3c 0.001). 24 individuals died at a median age of 43 years during the observation period. 29% of them had moderate and 71% severe CHD corresponding to a mortality rate of 0%, 0.29% and 1.68% per patient-year in ACHD with mild, moderate and severe CHD. Long-term survival was significantly reduced in patients with severe CHD in comparison to individuals with mild and moderate CHD (p \u3c 0.001). Conclusion: After correction or palliation of CHD, there was remarkable ongoing morbidity and mortality in ACHD patients over the 15-year observation period, particularly in individuals with moderate and severe CHD when compared with the general population. Thus, life-long special care is required for all surgically corrected or palliated ACHD patients. Graphical abstract: [Figure not available: see fulltext.
Design of broadband filters and antennas for SAMBA
We present a design for multipixel, multiband submillimeter instrument: SAMBA (Superconducting Antenna-coupled, Multi-frequency, Bolometric Array). SAMBA uses antenna coupled bolometers and microstrip filters. The concept allows for a much more compact, multiband imager compared to a comparable feedhorn-coupled bolometric system. SAMBA incorporates an array of slot antennas, superconducting transmission lines, a wide band multiplexer and superconducting transition edge bolometers. The transition-edge film measures the millimeter-wave power deposited in the resistor that terminates the transmission line
Optical design of the EPIC-IM crossed Dragone telescope
The Experimental Probe of Inflationary Cosmology - Intermediate Mission (EPIC-IM) is a concept for the NASA Einstein Inflation Probe satellite. EPIC-IM is designed to characterize the polarization properties of the Cosmic Microwave Background to search for the B-mode polarization signal characteristic of gravitational waves generated during the epoch of Inflation in the early universe. EPIC-IM employs a large focal plane with 11,000 detectors operating in 9 wavelength bands to provide 30 times higher sensitivity than the currently operating Planck satellite. The optical design is based on a wide-field 1.4 m crossed-Dragone telescope, an aperture that allows not only comprehensive measurements of Inflationary B-mode polarization, but also measurements of the E-mode and lensing polarization signals to cosmological limits, as well as all-sky maps of Galactic polarization with unmatched sensitivity and angular resolution. The optics are critical to measuring these extremely faint polarization signals, and any design must meet demanding requirements on systematic error control. We describe the EPIC-IM crossed Dragone optical design, its polarization properties, and far-sidelobe response
TrustNShare Partizipativ entwickeltes, Smart-contract basiertes Datentreuhandmodell mit skalierbarem Vertrauen und Inzentivierung
Überblick über die Ziele, Projektpartner (DLR, UKB, UKJ) und Aufgabenbereiche des Projekts "TrusNShare". Fokus liegt auf der Erläuterung des geplanten Treuhandmodells, der Partizipativen Entwicklung möglicher Anreize und der "Healthy Navigation App"
Кейсовый метод обучения при преподавании дисциплины "Стоматология детского возраста и профилактика стоматологических заболеваний"
ОБРАЗОВАНИЕ МЕДИЦИНСКОЕМЕДИЦИНСКИЕ УЧЕБНЫЕ ЗАВЕДЕНИЯКЕЙС-МЕТОДКЕЙСОВЫЙ МЕТОДСТОМАТОЛОГИЯ ДЕТСКОГО ВОЗРАСТА И ПРОФИЛАКТИКА СТОМАТОЛОГИЧЕСКИХ ЗАБОЛЕВАНИЙ (ДИСЦИПЛИНА)ИННОВАЦИОННЫЕ МЕТОДЫ ОБУЧЕНИЯСТУДЕНТЫ МЕДИЦИНСКИХ УЧЕБНЫХ ЗАВЕДЕНИ
A complete view of galaxy evolution: panchromatic luminosity functions and the generation of metals
When and how did galaxies form and their metals accumulate? Over the last
decade, this has moved from an archeological question to a live investigation:
there is now a broad picture of the evolution of galaxies in dark matter halos:
their masses, stars, metals and supermassive blackholes. Galaxies have been
found and studied in which these formation processes are taking place most
vigorously, all the way back in cosmic time to when the intergalactic medium
(IGM) was still largely neutral. However, the details of how and why the
interstellar medium (ISM) in distant galaxies cools, is processed, recycled and
enriched in metals by stars, and fuels active galactic nuclei (AGNs) remain
uncertain. In particular, the cooling of gas to fuel star formation, and the
chemistry and physics of the most intensely active regions is hidden from view
at optical wavelengths, but can be seen and diagnosed at mid- & far-infrared
(IR) wavelengths. Rest-frame IR observations are important first to identify
the most luminous, interesting and important galaxies, secondly to quantify
accurately their total luminosity, and finally to use spectroscopy to trace the
conditions in the molecular and atomic gas out of which stars form. In order to
map out these processes over the full range of environments and large-scale
structures found in the universe - from the densest clusters of galaxies to the
emptiest voids - we require tools for deep, large area surveys, of millions of
galaxies out to z~5, and for detailed follow-up spectroscopy. The necessary
tools can be realized technically. Here, we outline the requirements for
gathering the crucial information to build, validate and challenge models of
galaxy evolution.Comment: A whitepaper submitted on 15th February 2009 in response to the call
from the Astro2010 panel: astro2010.org; uploaded as an 8-page pdf fil
Transition-edge superconducting antenna-coupled bolometer
We report test results for a single pixel antenna-coupled bolometric detector. Our device consists of a dual slot microstrip antenna coupled to an Al/Ti/Au voltage-biased transition edge superconducting bolometer (TES). The coupling architecture involves propagating the signal along superconducting microstrip lines and terminating the lines at a normal metal resistor colocated with a TES on a thermally isolated island. The device, which is inherently polarization sensitive, is optimized for 140 GHz band measurements. In the thermal bandwidth of the TES, we measure a noise equivalent power of 2.0 × 10^(-17) W/√Hz in dark tests that agrees with calculated NEP including only contributions from thermal, Johnson and amplifier noise. We do not measure any excess noise at frequencies between 1 and 200 Hz. We measure a thermal conductance G ~5.5 × 10^(-11) W/K. We measure a thermal time constant as low as 437μs at 3μV bias when stimulating the TES directly using an LED
Thermal Kinetic Inductance Detectors for millimeter-wave detection
Thermal Kinetic Inductance Detectors (TKIDs) combine the excellent noise
performance of traditional bolometers with a radio frequency multiplexing
architecture that enables the large detector counts needed for the next
generation of millimeter-wave instruments. In this paper, we first discuss the
expected noise sources in TKIDs and derive the limits where the phonon noise
contribution dominates over the other detector noise terms:
generation-recombination, amplifier, and two-level system (TLS) noise. Second,
we characterize aluminum TKIDs in a dark environment. We present measurements
of TKID resonators with quality factors of about at 80 mK. We also
discuss the bolometer thermal conductance, heat capacity, and time constants.
These were measured by the use of a resistor on the thermal island to excite
the bolometers. These dark aluminum TKIDs demonstrate a noise equivalent power
NEP = , with a knee at
0.1 Hz, which provides background noise limited performance for ground-based
telescopes observing at 150 GHz.Comment: 15 pages, 12 figure
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