Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
J Low Temp Phys ; 199(3-4)2020.
Artigo em Inglês | MEDLINE | ID: mdl-33487736

RESUMO

We describe the design and measurement of feedhorn-coupled, transition-edge sensor (TES) polarimeters with two passbands centered at 220 GHz and 280 GHz, intended for observations of the cosmic microwave background. Each pixel couples polarized light in two linear polarizations by use of a planar orthomode transducer and senses power via four TES bolometers, one for each band in each linear polarization. Previous designs of this detector architecture incorporated passbands from 27 to 220 GHz; we now demonstrate this technology at frequencies up to 315 GHz. Observational passbands are defined with an on-chip diplexer, and Fourier-transform-spectrometer measurements are in excellent agreement with simulations. We find coupling from feedhorn to TES bolometer using a cryogenic, temperature-controlled thermal source. We determine the optical efficiency of our device is η = 77% ± 6% (75% ± 5%) for 220 (280) GHz, relative to the designed passband shapes. Lastly, we compare two power-termination schemes commonly used in wide-bandwidth millimeter-wave polarimeters and find equal performance in terms of optical efficiency and passband shape.

2.
J Low Temp Phys ; 193(3-4)2018.
Artigo em Inglês | MEDLINE | ID: mdl-34815585

RESUMO

Microwave Kinetic Inductance Detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the development of feedhorn-coupled MKID detectors for the TolTEC millimeter-wave imaging polarimeter being constructed for the 50-meter Large Millimeter Telescope (LMT). Observations with TolTEC are planned to begin in early 2019. TolTEC will comprise ∼7,000 polarization sensitive MKIDs and will represent the first MKID arrays fabricated and deployed on monolithic 150 mm diameter silicon wafers - a critical step towards future large-scale experiments with over 105 detectors. TolTEC will operate in observational bands at 1.1, 1.4, and 2.0 mm and will use dichroic filters to define a physically independent focal plane for each passband, thus allowing the polarimeters to use simple, direct-absorption inductive structures that are impedance matched to incident radiation. This work is part of a larger program at NIST-Boulder to develop MKID-based detector technologies for use over a wide range of photon energies spanning millimeter-waves to X-rays. We present the detailed pixel layout and describe the methods, tools, and flexible design parameters that allow this solution to be optimized for use anywhere in the millimeter and sub-millimeter bands. We also present measurements of prototype devices operating in the 1.1 mm band and compare the observed optical performance to that predicted from models and simulations.

3.
Appl Phys Lett ; 111(24)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29335654

RESUMO

Key performance characteristics are demonstrated for the microwave SQUID multiplexer (µmux) coupled to transition edge sensor (TES) bolometers that have been optimized for cosmic microwave background (CMB) observations. In a 64-channel demonstration, we show that the µmux produces a white, input referred current noise level of [Formula: see text] at -77 dB microwave probe tone power, which is well below expected fundamental detector and photon noise sources for a ground-based CMB-optimized bolometer. Operated with negligible photon loading, we measure [Formula: see text] in the TES-coupled channels biased at 65% of the sensor normal resistance. This noise level is consistent with that predicted from bolometer thermal fluctuation (i.e. phonon) noise. Furthermore, the power spectral density is white over a range of frequencies down to ~ 100 mHz, which enables CMB mapping on large angular scales that constrain the physics of inflation. Additionally, we report cross-talk measurements that indicate a level below 0.3%, which is less than the level of cross-talk from multiplexed readout systems in deployed CMB imagers. These measurements demonstrate the µmux as a viable readout technique for future CMB imaging instruments.

4.
Psychiatr Neurol Med Psychol (Leipz) ; 39(9): 551-6, 1987 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-3432445

RESUMO

The comparison of 300 infant and adolescent psychiatric patients with 300 healthy persons of the same age group has shown a number of significant differences. The patients frequently come from incomplete families or divorced marriages; they are also exposed to unsuitable educational styles. There are more first-born children and more accentuated personalities in this group. Further differences worthwhile interpreting are traceable between psychoneurotic and psychosomatic patients.


Assuntos
Transtornos do Comportamento Infantil/psicologia , Família , Transtornos Neuróticos/psicologia , Desenvolvimento da Personalidade , Transtornos Psicofisiológicos/psicologia , Adolescente , Criança , Educação Infantil , Pré-Escolar , Características da Família , Feminino , Humanos , Masculino , Fatores de Risco , Meio Social
5.
Psychiatr Neurol Med Psychol (Leipz) ; 37(5): 280-3, 1985 May.
Artigo em Alemão | MEDLINE | ID: mdl-3875113

RESUMO

The decrease of neurological illnesses and the corresponding increase of psychogenic disturbances by patients belonging to clinical departments of neuropsychiatry of child and youth are described. This conversion leads to a frequently longer staying of the patients within the clinics. Furthermore, changes of the behaviours of the whole team for treatment may be observed.


Assuntos
Transtornos Neurocognitivos/epidemiologia , Adolescente , Criança , Estudos Transversais , Epilepsia/epidemiologia , Alemanha Oriental , Hospitais Psiquiátricos , Humanos , Inteligência , Deficiências da Aprendizagem/epidemiologia , Transtornos Neurocognitivos/terapia , Transtornos Neuróticos/epidemiologia , Relações Profissional-Paciente , Transtornos Psicofisiológicos/epidemiologia , Psicoterapia
6.
Psychiatr Neurol Med Psychol (Leipz) ; 33(3): 182-8, 1981 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-7244043

RESUMO

Most of the 151 young feeble-minded adults examined by us prove to be successful at their work-places. In most cases, these work-places require a relatively low degree of qualification. The mentally disabled male persons gain on an average a higher income; often they do heavy physical work and show a higher accident risk than the female persons questioned by us. In a considerable part of the feeble-minded test persons our questioning revealed great differences between the subjective appraisal of their social recognition and the objective appraisal of the social value made by the enterprise. These divergences decrease with increasing age of the test persons. The majority of the oligophrenic young adults are not doing any social work.


Assuntos
Educação de Pessoa com Deficiência Intelectual , Reabilitação Vocacional/métodos , Adolescente , Adulto , Feminino , Humanos , Satisfação no Emprego , Masculino , Motivação , Fatores Sexuais , Ajustamento Social
8.
Psychiatr Neurol Med Psychol (Leipz) ; 32(2): 87-91, 1980 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-7394085

RESUMO

A standardised questioning of 151 former pupils of a school for backward children aged 18 to 28 years on leisure-time and consuming habits, partner relations and living conditions showed a relatively satisfactory integration. There were qualitative particularities with respect to leisure-time occupations, also in dependence upon the course of education, but not with respect to consuming habits. No indications of an accumulation of alcohol abuse were found. The share of married and engaged persons was relatively small. The cohabitation age was clearly lower, the number of illegitimate children higher than among the normal population. A separate report will be given on the efficiency in vocational activities.


Assuntos
Deficiência Intelectual/psicologia , Ajustamento Social , Transtornos do Comportamento Social/psicologia , Atividades Cotidianas , Adolescente , Adulto , Feminino , Humanos , Atividades de Lazer , Masculino , Casamento , Reabilitação Vocacional
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA