scholarly journals Fully Superconducting Josephson Bolometers for Gigahertz Astronomy

2021 ◽  
Vol 11 (2) ◽  
pp. 746
Author(s):  
Federico Paolucci ◽  
Nadia Ligato ◽  
Gaia Germanese ◽  
Vittorio Buccheri ◽  
Francesco Giazotto
Keyword(s):  
Background Radiation ◽  
State Of The Art ◽  
Transition Edge Sensor ◽  
Thermal Characterization ◽  
Device Fabrication ◽  
Experimental Realization ◽  
One Dimensional ◽  
Transition Edge ◽  
Tunable Sensors ◽  
The Universe

The origin and the evolution of the universe are concealed in the evanescent diffuse extragalactic background radiation (DEBRA). To reveal these signals, the development of innovative ultra-sensitive bolometers operating in the gigahertz band is required. Here, we review the design and experimental realization of two bias-current-tunable sensors based on one dimensional fully superconducting Josephson junctions: the nanoscale transition edge sensor (nano-TES) and the Josephson escape sensor (JES). In particular, we cover the theoretical basis of the sensors operation, the device fabrication, their experimental electronic and thermal characterization and the deduced detection performance. Indeed, the nano-TES promises a state-of-the-art noise equivalent power (NEP) of about 5×10−20 W/Hz, while the JES active region is expected to show an unprecedented NEP of the order of 10−25 W/Hz. Therefore, the nano-TES and JES are strong candidates to push radio astronomy to the next level.

State-of-the-Art of Modeling Surface Water Impoundments

1982 ◽  
Vol 14 (1-2) ◽  
pp. 241-261 ◽  
Author(s):  
P A Krenkel ◽  
R H French
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
State Of The Art ◽  
Rate Coefficients ◽  
Two Dimensional ◽  
One Dimensional ◽  
Integral Energy ◽  
Range Of Values ◽  
Dimensional Integral ◽  
Water Impoundment

The state-of-the-art of surface water impoundment modeling is examined from the viewpoints of both hydrodynamics and water quality. In the area of hydrodynamics current one dimensional integral energy and two dimensional models are discussed. In the area of water quality, the formulations used for various parameters are presented with a range of values for the associated rate coefficients.

The experience of employment of the mathematical cartography methods in cosmology

2017 ◽  
Vol 923 (5) ◽  
pp. 7-16
Author(s):  
A.V. Kavrayskiy
Keyword(s):  
Background Radiation ◽  
Three Dimensional ◽  
Spherical Coordinates ◽  
Linear Element ◽  
Microwave Background ◽  
Euclidian Space ◽  
Microwave Background Radiation ◽  
Rectangular Coordinates ◽  
The Universe ◽  
Length Distortion

The experience of mathematical modeling of the 3D-sphere in the 4D-space and projecting it by mathematical cartography methods in the 3D-Euclidian space is presented. The problem is solved by introduction of spherical coordinates for the 3D-sphere and their transformation into the rectangular coordinates, using the mathematical cartography methods. The mathematical relationship for calculating the length distortion mp(s) of the ds linear element when projecting the 3D-sphere from the 4-dimensional Euclidian space into three-dimensional Euclidian space is derived. Numerical examples, containing the modeling of the ds small linear element by spherical coordinates of 3D-sphere, projecting this sphere into the 3D-Euclidian space and length of ds calculating by means of its projection dL and size of distortion mp(s) are solved. Based on the model of the Universe known in cosmology as the 3D-sphere, the hypothesis of connection between distortion mp(s) and the known observed effects Redshift and Microwave Background Radiation is considered.

scholarly journals Excess Heat Capacity in Mo/Au Transition Edge Sensor Bolometric Detectors

2021 ◽  
pp. 1-1
Author(s):  
Ari David Brown ◽  
Regis Brekosky ◽  
Felipe Colazo-Petit ◽  
Matthew Greenhouse ◽  
James Hay-Wehle ◽  
...  
Keyword(s):  
Heat Capacity ◽  
Transition Edge Sensor ◽  
Excess Heat Capacity ◽  
Excess Heat ◽  
Bolometric Detectors ◽  
Transition Edge

scholarly journals Performance and uniformity of a kilo-pixel array of Ti/Au transition-edge sensor microcalorimeters

2021 ◽  
Vol 92 (2) ◽  
pp. 023101
Author(s):  
E. Taralli ◽  
M. D’Andrea ◽  
L. Gottardi ◽  
K. Nagayoshi ◽  
M. L. Ridder ◽  
...  
Keyword(s):  
Transition Edge Sensor ◽  
Transition Edge ◽  
Pixel Array

scholarly journals Influence of the Interface Composition to the Superconductivity of Ti/PdAu Films

Nanomaterials ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 39
Author(s):  
Xiaolong Xu ◽  
Mauro Rajteri ◽  
Jinjin Li ◽  
Shuo Zhang ◽  
Jian Chen ◽  
...  
Keyword(s):  
Transition Edge Sensor ◽  
Energy Dispersive Spectrometer ◽  
Annealing Process ◽  
Bilayer Film ◽  
Superconducting Transition ◽  
Infiltration Process ◽  
Interface Composition ◽  
Transition Edge ◽  
Transmission Electron ◽  
Function Unit

In this work, the interface composition of the superconducting Ti/PdAu bilayer is tuned by an annealing process in N2 from 100 to 500 °C to control the superconducting transition temperature (Tc). This Ti-PdAu composition layer is characterized with a high-resolution transmission electron microscopy (HRTEM) and energy-dispersive spectrometer (EDS) to show the infiltration process. The surface topography, electrical, and cryogenic properties are also shown. The inter-infiltration of Ti and PdAu induced by the thermal treatments generates an intermixed layer at the interface of the bilayer film. Due to the enforced proximity effect by the annealing process, the Tc of Ti (55 nm)/PdAu (60 nm) bilayer thin films is tuned from an initial value of 243 to 111 mK which is a temperature that is suitable for the application as the function unit of a superconducting transition edge sensor.

Modelling the Resistive State in a Transition Edge Sensor

2012 ◽  
Vol 167 (3-4) ◽  
pp. 114-120
Author(s):  
A. Kozorezov ◽  
A. A. Golubov ◽  
D. D. E. Martin ◽  
P. A. J. de Korte ◽  
M. A. Lindeman ◽  
...  
Keyword(s):  
Transition Edge Sensor ◽  
Resistive State ◽  
Transition Edge

scholarly journals Thermal fluctuation noise in Mo/Au superconducting transition-edge sensor microcalorimeters

2019 ◽  
Vol 125 (16) ◽  
pp. 164503 ◽  
Author(s):  
N. A. Wakeham ◽  
J. S. Adams ◽  
S. R. Bandler ◽  
S. Beaumont ◽  
J. A. Chervenak ◽  
...  
Keyword(s):  
Transition Edge Sensor ◽  
Thermal Fluctuation ◽  
Superconducting Transition ◽  
Transition Edge ◽  
Fluctuation Noise

scholarly journals Background Light from Population III Stars

1987 ◽  
Vol 117 ◽  
pp. 414-414
Author(s):  
Jonathan C. McDowell
Keyword(s):  
Dark Matter ◽  
Background Radiation ◽  
Large Fraction ◽  
Rest Mass ◽  
Critical Density ◽  
Density Parameter ◽  
Extragalactic Background Light ◽  
Background Light ◽  
Far Ultraviolet ◽  
The Universe

It has been proposed (e.g. Carr, Bond and Arnett 1984) that the first generation of stars may have been Very Massive Objects (VMOs, of mass above 200 M⊙) which existed at large redshifts and left a large fraction of the mass of the universe in black hole remnants which now provide the dynamical ‘dark matter’. The radiation from these stars would be present today as extragalactic background light. For stars with density parameter Ω* which convert a fraction ϵ of their rest-mass to radiation at a redshift of z, the energy density of background radiation in units of the critical density is ΩR = εΩ* / (1+z). The VMOs would be far-ultraviolet sources with effective temperatures of 105 K. If the radiation is not absorbed, the constraints provided by measurements of background radiation imply (for H =50 km/s/Mpc) that the stars cannot close the universe unless they formed at a redshift of 40 or more. To provide the dark matter (of one-tenth closure density) the optical limits imply that they must have existed at redshifts above 25.

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