Articles de revues : « Bolometri »

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Ahmad Beig, Mirza Tanweer, Mukesh Kumar, Yogesh Sharma et Bhoopesh Kumar Sharma. « A Terahertz/Millimeter-Wave Based Detection and Imaging System Using Antenna-Coupled Microbolometer ». Journal of Physics : Conference Series 2335, n^o 1 (1 septembre 2022) : 012005. http://dx.doi.org/10.1088/1742-6596/2335/1/012005.

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Abstract The Terahertz (THz) region lie in the range 0.1 THz to 10 THz. It can pass easily through fog, smoke, thin walls, and clothes and be focused as a light wave to create images of objects. Terahertz waves are applied in imaging technology, such as safety, navigation, and non-destructive evaluation (NDE) technique used for materials analysis. A microbolometer is a micromachined device to measure the inherent power of incident electromagnetic radiation. The resistance of bolometer is temperature-dependent, and it varies with changes in the temperature of the exposed surface. Bolometric detectors dominate the market due to their affordability and ease of manufacturing. Despite their slow response time, the systems are still actively employed in the research area, aiming at improved terahertz detection. The antenna and bolometer are coupled. The chosen antenna has a resonance at desired frequency leading to the development of fast response time bolometers without compromising the collection area of the bolometer. The system has low cost, easy fabrication, and better isolation. Antenna simulations were conducted to design and optimize the spiral antenna for 1 to 2.5 THz using HFSS (high-frequency structure simulator) simulation software. The antenna simulation results are presented and discussed.

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Poda, Denys, et Andrea Giuliani. « Low background techniques in bolometers for double-beta decay search ». International Journal of Modern Physics A 32, n^o 30 (30 octobre 2017) : 1743012. http://dx.doi.org/10.1142/s0217751x17430126.

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Bolometers are low temperature particle detectors with high energy resolution and detection efficiency. Some types of bolometric detectors are also able to perform an efficient particle identification. A wide variety of radiopure dielectric and diamagnetic materials makes the bolometric technique favorable for applications in astroparticle physics. In particular, thanks to their superior performance, bolometers play an important role in the worldwide efforts on searches for neutrinoless double-beta decay. Such experiments strongly require an extremely low level of the backgrounds that can easily mimic the process searched for. Here, we overview recent progress in the development of low background techniques for bolometric double-beta decay searches.

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KHREBTOV, I. A. « NOISE PROPERTIES OF HIGH TEMPERATURE SUPERCONDUCTING BOLOMETERS ». Fluctuation and Noise Letters 02, n^o 02 (juin 2002) : R51—R70. http://dx.doi.org/10.1142/s0219477502000671.

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The review describes the noise properties of the high temperature superconducting (HTS) bolometers developed for the applications in the optical electronic devices of infrared and submillimeter wave-lengths. The principle of high-Tc transition edge bolometer operation and bolometer noise theory are considered, taking into account the peculiarities of constant bias current and constant bias voltage modes. The published results of bolometer noise modeling are discussed. Various sources of the excess 1/f-noise in HTS films as temperature sensitive element for bolometer are reviewed, including the experimental data and modern noise models. Comparative analysis of noise characteristics of the most developed HTS bolometers for application (antenna-coupled microbolometers and bolometers based on silicon micromachining technology) is reported.

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Uddin, Nezam, Qiwen Sheng, Seungsup Lee, Matthew L. Reinke, David Donovan, Morgan Shafer et Ming Han. « Multichannel Fiber-Optic Silicon Fabry–Pérot Interferometric Bolometer System for Plasma Radiation Measurements ». Photonics 8, n^o 9 (25 août 2021) : 344. http://dx.doi.org/10.3390/photonics8090344.

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A single-channel fiber-optic bolometer system based on a high-finesse silicon Fabry–Pérot interferometer (FPI) was previously reported, intended to measure plasma radiation from the magnetically confined fusion chamber. Recently, we developed a multichannel fiber-optic bolometer system with five bolometers multiplexed using a coarse wavelength division multiplexer (CWDM) and interrogated with a white-light system involving a superluminescent light-emission diode source and a high-speed spectrometer. One of the bolometers was used as the reference bolometer to compensate for the ambient temperature variations, and the other four bolometers were used for radiation measurement. The bolometers have a simple structure with a silicon pillar at the end of the single-mode fiber and a gold disk on the other side of the silicon pillar. They are also easy to fabricate without stringent requirements on the optical alignment. Analysis of the system optimization was performed to improve the noise performance and to mitigate the vibration effect that may present in the practical application. The system had a significantly enhanced measurement range compared to the previous high-finesse FPI bolometer system for measuring radiation. Test results performed in air using a 405 nm laser as the radiation source showed that the temperature resolution and the noise-equivalent power density of the sensing bolometers connected to each channel of the CWDM were, respectively, ~0.4 mK and ~0.1 W/m2, with a time constant of ~220 ms, which is comparable to the previous more complicated fiber-optic bolometer systems based on high-finesse FPIs that were interrogated using wavelength-scanning lasers.

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Federici, Fabio, Matthew L. Reinke, Bruce Lipschultz, Andrew J. Thornton, James R. Harrison, Jack J. Lovell et Matthias Bernert. « Design and implementation of a prototype infrared video bolometer (IRVB) in MAST Upgrade ». Review of Scientific Instruments 94, n^o 3 (1 mars 2023) : 033502. http://dx.doi.org/10.1063/5.0128768.

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A prototype infrared video bolometer (IRVB) was successfully deployed in the Mega Ampere Spherical Tokamak Upgrade (MAST Upgrade or MAST-U), the first deployment of such a diagnostic in a spherical tokamak. The IRVB was designed to study the radiation around the lower x-point, another first in tokamaks, and has the potential to estimate emissivity profiles with spatial resolution beyond what is achievable with resistive bolometry. The system was fully characterized prior to installation on MAST-U, and the results are summarized here. After installation, it was verified that the actual measurement geometry in the tokamak qualitatively matches the design; this is a particularly difficult process for bolometers and was done using specific features of the plasma itself. The installed IRVB measurements are consistent both with observations from other diagnostics, including magnetic reconstruction, visible light cameras, and resistive bolometry, as well as with the IRVB-designed view. Early results show that with conventional divertor geometry and only intrinsic impurities (for example, C and He), the progression of radiative detachment follows a similar path to that observed for large aspect ratio tokamaks: The peak of the radiation moves along the separatrix from the targets to the x-point and high-field side midplane with a toroidally symmetric structure that can eventually lead to strong effects on the core plasma inside the separatrix.

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Юсупов, Р. А., А. А. Гунбина, А. М. Чекушкин, Д. В. Нагирная, С. А. Лемзяков, В. С. Эдельман et М. А. Тарасов. « Квантовый отклик болометра на основе структуры СИНИС с подвешенным абсорбером ». Физика твердого тела 62, n^o 9 (2020) : 1403. http://dx.doi.org/10.21883/ftt.2020.09.49761.11h.

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Bolometers based on the structure of a superconductor - insulator - normal metal - insulator - superconductor with an absorber suspended above the substrate have been developed, manufactured, and experimentally investigated in the THz frequency range. In such structures, in contrast to the previously studied bolometers with an absorber located directly on the substrate, the bolometric mode of operation of the receiver is realized, i.e., more than one electron is excited per quantum of radiation (quantum efficiency greater than 1). In the studied bolometers, it was possible to achieve a quantum efficiency of 15 electrons per radiation quantum with a frequency of 350 GHz.

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Демьяненко, М. А., et В. В. Старцев. « Применение неохлаждаемых микроболометров для регистрации импульсного терагерцового и инфракрасного излучения ». Журнал технической физики 92, n^o 3 (2022) : 443. http://dx.doi.org/10.21883/jtf.2022.03.52139.190-21.

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Analytical relations for temperature response of the bolometer to periodic radiation pulses are obtained. It is theoretically shown and experimentally confirmed by the example of infrared bolometers that when detecting short radiation pulses, in contrast to the case of constant radiation, increasing the thermal conductivity of the bolometer and, accordingly, decreasing its thermal relaxation time, it is possible to significantly increase the response rate of the receiver, practically without reducing its sensitivity. The possibility of effective registration of pulsed terahertz radiation by microbolometers with a resistively coupled, thermally non-isolated antenna is considered. It is shown that such bolometers, which have increased thermal conductivity and, accordingly, reduced sensitivity to continuous-wave radiation, can be highly effective when detecting pulsed radiation with a duration shorter than the thermal relaxation time of the bolometer. On their basis, uncooled matrix detectors of pulsed terahertz radiation, characterized by a minimum detectable energy of less than 110-12 J and a frame rate of up to 1000 Hz, can be developed.

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Zolotarova, Anastasiia. « Bolometric Double Beta Decay Experiments : Review and Prospects ». Symmetry 13, n^o 12 (26 novembre 2021) : 2255. http://dx.doi.org/10.3390/sym13122255.

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This review aims to cover the history and recent developments on cryogenic bolometers for neutrinoless double beta decay (0ν2β) searches. A 0ν2β decay observation would confirm the total lepton charge non-conservation, which is related to a global U(1)LC symmetry. This discovery would also provide essential information on neutrino masses and nature, opening the door to new physics beyond the Standard Model. The bolometric technology shows good prospects for future ton-scale experiments that aim to fully investigate the inverted ordering region of neutrino masses. The big advantage of bolometers is the high energy resolution and the possibility of particle identification, as well as various methods of additional background rejection. The CUORE experiment has proved the feasibility of ton-scale cryogenic experiments, setting the most stringent limit on 130Te 0ν2β decay. Two CUPID demonstrators (CUPID-0 and CUPID-Mo) have set the most stringent limits on 82Se and 100Mo isotopes, respectively, with compatibly low exposures. Several experiments are developing new methods to improve the background in the region of interest with bolometric detectors. CUPID and AMoRE experiments aim to cover the inverted hierarchy region, using scintillating bolometers with hundreds of kg of 100Mo. We review all of these efforts here, with a focus on the different types of radioactive background and the measures put in place to mitigate them.

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Ma, He, Xinping Zhang, Zhichao Zhang, Yu Wang, Guang Wang, Feifei Liu, Ruixue Cui et al. « Infrared micro-detectors with high sensitivity and high response speed using VO2-coated helical carbon nanocoils ». Journal of Materials Chemistry C 7, n^o 39 (2019) : 12095–103. http://dx.doi.org/10.1039/c9tc02833a.

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Dem'yanenko M. A. et Startsev V. V. « Application of uncooled microbolometers for detecting pulsed terahertz and infrared radiation ». Technical Physics 92, n^o 3 (2022) : 359. http://dx.doi.org/10.21883/tp.2022.03.53266.190-21.

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Analytical relations for temperature response of the bolometer to periodic radiation pulses are obtained. It is theoretically shown and experimentally confirmed by the example of infrared bolometers that when detecting short radiation pulses, in contrast to the case of constant radiation, increasing the thermal conductivity of the bolometer and, accordingly, decreasing its thermal relaxation time, it is possible to significantly increase the response rate of the receiver, practically without reducing its sensitivity. The possibility of effective registration of pulsed terahertz radiation by microbolometers with a resistively coupled, thermally non-isolated antenna is considered. It is shown that such bolometers, which have increased thermal conductivity and, accordingly, reduced sensitivity to continuous-wave radiation, can be highly effective when detecting pulsed radiation with a duration shorter than the thermal relaxation time of the bolometer. On their basis, uncooled matrix detectors of pulsed terahertz radiation, characterized by a minimum detectable energy of less than 1·10-12 J and a frame rate of up to 1000 Hz, can be developed. Keywords: microbolometer, pulsed terahertz radiation, antenna.

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Dao, Thang Duy, Anh Tung Doan, Satoshi Ishii, Takahiro Yokoyama, Handegård Sele Ørjan, Dang Hai Ngo, Tomoko Ohki et al. « MEMS-Based Wavelength-Selective Bolometers ». Micromachines 10, n^o 6 (21 juin 2019) : 416. http://dx.doi.org/10.3390/mi10060416.

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We propose and experimentally demonstrate a compact design for membrane-supported wavelength-selective infrared (IR) bolometers. The proposed bolometer device is composed of wavelength-selective absorbers functioning as the efficient spectroscopic IR light-to-heat transducers that make the amorphous silicon (a-Si) bolometers respond at the desired resonance wavelengths. The proposed devices with specific resonances are first numerically simulated to obtain the optimal geometrical parameters and then experimentally realized. The fabricated devices exhibit a wide resonance tunability in the mid-wavelength IR atmospheric window by changing the size of the resonator of the devices. The measured spectral response of the fabricated device wholly follows the pre-designed resonance, which obviously evidences that the concept of the proposed wavelength-selective IR bolometers is realizable. The results obtained in this work provide a new solution for on-chip MEMS-based wavelength-selective a-Si bolometers for practical applications in IR spectroscopic devices.

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MONTICONE, E. « ELECTRO-THERMAL RESPONSE OF A VOLTAGE-BIASED HIGH-TC BOLOMETER ». International Journal of Modern Physics B 17, n^o 04n06 (10 mars 2003) : 740–44. http://dx.doi.org/10.1142/s0217979203016534.

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The characteristics of voltage biased HTc bolometers have been analysed by numerically solving the heat continuity equation of the system for ohmic and non-ohmic behaviour. The solutions show that the time constant and the linearity range of response depend strongly on biasing condition. For a bolometer in ohmic regime and operating in strong electrothermal feedback, the time constant can be reduced of more of one order of magnitude and linearity range increased of about 100 times with respect to the same device biased at low bias voltage. More limited improvements are obtained if the bolometer is in non-ohmic regime.

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Nandi, Sukanta, Vinod Panwar et Abha Misra. « Metal-carbon nanotube composite for wavelength-selective bolometer with improved characteristics ». Journal of Applied Physics 133, n^o 4 (28 janvier 2023) : 043104. http://dx.doi.org/10.1063/5.0129993.

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This work comprehensively discusses the utilization of a metal-multiwalled carbon nanotube (CNT) nanocomposite of gold (Au)/CNT for uncooled bolometric application synthesized by a simple rapid green synthesis technique. Enhanced light–matter interaction with the visible (532 nm) and near-infrared (1064 nm) radiations in the nanocomposite is utilized for achieving improved bolometric response at room temperature (RT, ∼300 K). A comparatively higher temperature coefficient of resistance of ∼−0.11%/K (improvement of ∼57%) was achieved in the Au/CNT nanocomposite bolometer (BM). Additionally, the composite BM demonstrated a dual (532 and 1064 nm) spectral selectively and enhanced sensitivity with respective large RT voltage responsivities of ∼11.70 ± 3.45 V/W and ∼503.54 ± 12.77 mV/W, as opposed to null response from the CNT BM. The current study, thus, demonstrates an important step toward designing high-performing CNT BMs for uncooled operation, with added functionality of wavelength-selectiveness.

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Prudkovskii, Pavel, Andrey Leontyev, Kirill Kuznetsov et Galiya Kitaeva. « Towards Measuring Terahertz Photon Statistics by a Superconducting Bolometer ». Sensors 21, n^o 15 (21 juillet 2021) : 4964. http://dx.doi.org/10.3390/s21154964.

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Statistical distributions of the analog readings of an antenna-coupled THz superconducting bolometer were measured and analyzed under a special type of irradiation by low-energy fluxes of THz photons with Poisson photon statistics and controllable mean photon numbers. The photons were generated via low-gain parametric down-conversion in pulse-pumped Mg:LiNbO3 crystal placed to a cooled cryostat together with the bolometer NbN film. Results of theoretical approximation of experimental histograms reveal the discrete nature of THz detection by superconducting bolometers and open a way for studying their quantum characteristics. It is shown that bolometer readings per pulse consist of discrete counts (“single charges”), with the mean number linearly dependent on the number of input photons. Contributions of single counts to a total analog reading are statistically distributed according to the normal law, with average values slightly depending on the number of counts in each reading. A general formula is proposed to describe the relationship between continuous statistical distribution of the bolometer readings and discrete quantum statistics of the incident photons.

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Lindeman, M. A. « Resonator-bolometer theory, microwave read out, and kinetic inductance bolometers ». Journal of Applied Physics 116, n^o 2 (14 juillet 2014) : 024506. http://dx.doi.org/10.1063/1.4890018.

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El Fatimy, Abdel, Anindya Nath, Byoung Don Kong, Anthony K. Boyd, Rachael L. Myers-Ward, Kevin M. Daniels, M. Mehdi Jadidi, Thomas E. Murphy, D. Kurt Gaskill et Paola Barbara. « Ultra-broadband photodetectors based on epitaxial graphene quantum dots ». Nanophotonics 7, n^o 4 (28 mars 2018) : 735–40. http://dx.doi.org/10.1515/nanoph-2017-0100.

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AbstractGraphene is an ideal material for hot-electron bolometers due to its low heat capacity and weak electron-phonon coupling. Nanostructuring graphene with quantum-dot constrictions yields detectors of electromagnetic radiation with extraordinarily high intrinsic responsivity, higher than 1×109 V W−1 at 3 K. The sensing mechanism is bolometric in nature: the quantum confinement gap causes a strong dependence of the electrical resistance on the electron temperature. Here, we show that this quantum confinement gap does not impose a limitation on the photon energy for light detection and these quantum-dot bolometers work in a very broad spectral range, from terahertz through telecom to ultraviolet radiation, with responsivity independent of wavelength. We also measure the power dependence of the response. Although the responsivity decreases with increasing power, it stays higher than 1×108 V W−1 in a wide range of absorbed power, from 1 pW to 0.4 nW.

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Alessandrello, A., C. Brofferio, C. Bucci, O. Cremonesi, E. Fiorini, A. Giuliani, A. Monfardini et al. « Milano Group Development of Bolometric Detectors : a 6.8Kg TeO2 bolometer array for ββ decay and high energy resolution μ-bolometers for nuclear and x-ray physics ». Nuclear Physics A 654, n^o 1 (juillet 1999) : 997c—1002c. http://dx.doi.org/10.1016/s0375-9474(00)88587-5.

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Lee, S., M. Shafer, M. Reinke, N. Uddin, Q. Sheng, M. Han, D. Donovan et R. O’Neill. « First demonstration of a fiber optic bolometer on a tokamak plasma (invited) ». Review of Scientific Instruments 93, n^o 12 (1 décembre 2022) : 123515. http://dx.doi.org/10.1063/5.0099546.

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A fiber optic bolometer (FOB) was demonstrated observing a fusion plasma for the first time at the DIII-D tokamak. A FOB uses a fiber optics-based interferometric technique that is designed to have a high sensitivity to temperature changes [75 mK/(W/m2) responsivity in high vacuum with 0.38 mK noise level] with a negligible susceptibility to electromagnetic interference (EMI) that can be problematic for resistive bolometers in a tokamak environment. A single-channel test apparatus was installed on DIII-D consisting of a measurement FOB and shielded reference FOB. The single-channel FOB showed a negligible increase in the noise level during typical plasma operations (0.39 mK) compared to the benchtop results (0.38 mK), confirming an insignificant EMI impact to the FOB. Comparisons to DIII-D resistive bolometers showed good agreement with the single-channel FOB, indicating that the FOB is comparable to a resistive bolometer when the impulse calibration is applied. The noise-equivalent power density of the calibrated FOB during a plasma operation was 0.55 W/m2 with an average sampling time of 20 ms. The major potential effect of ionizing radiation on the FOB would be the radiation-induced attenuation, which can be efficiently compensated for by adjusting the probing light power.

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Sheglov, D. V., M. A. Dem’yanenko, O. I. Semenova, S. V. Rodyakin, D. A. Nasimov, S. V. Sitnikov, D. I. Rogilo, L. I. Fedina, A. L. Aseev et A. V. Latyshev. « DEVELOPMENT OF A BROADBAND ELECTROMAGNETIC RADIATION ABSORBER BASED ON MULTIWALL CARBON NANOTUBES ; AND ITS APPLICATION IN BOLOMETRIC RECEIVERS ». RADIO COMMUNICATION TECHNOLOGY, n^o 51 (30 décembre 2021) : 75–88. http://dx.doi.org/10.33286/2075-8693-2021-51-75-88.

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This work is devoted to the development of a technique for obtaining an array of multi-walled vertically aligned carbon nanotubes (VACNT) with a thickness of up to 120 μm on Si/Al2O3/Fe substrates and to the study of their absorbing properties in the THz spectral region, as well as to the assessment of their prospects as a broadband THz radiation absorber based on calculations of the spectral dependence of absorption coefficient for traditional and inverted-type bolometric devices. It is shown that the absorption of the VACNT array transferred onto the Revalpha polymer substrate reaches 70–80% in the wavelength range of 40–200 µm. Calculations show that traditional bolometers with an absorber based on VACNT have the best sensitivity at wavelengths less than 100 μm, and inverted bolometers also having a VACNT layer have the best sensitivity at wavelengths exceeding 50 μm, which makes them complementary to each other.

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Semenov, A. D., K. Il’in, M. Siegel, A. Smirnov, S. Pavlov, H. Richter et H.-W. Hübers. « Evidence of non-bolometric mixing in the bandwidth of a hot-electron bolometer ». Superconductor Science and Technology 19, n^o 10 (11 septembre 2006) : 1051–56. http://dx.doi.org/10.1088/0953-2048/19/10/011.

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Kurtukova, Tatiana N., Daria S. Kopylova, Nikita I. Raginov, Eldar M. Khabushev, Ilya V. Novikov, Svetlana I. Serebrennikova, Dmitry V. Krasnikov et Albert G. Nasibulin. « Plasma-treated carbon nanotubes for fast infrared bolometers ». Applied Physics Letters 122, n^o 9 (27 février 2023) : 093501. http://dx.doi.org/10.1063/5.0140030.

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Carbon nanotube films are a promising class of materials for bolometric photodetectors due to a unique combination of extremely thin (nm-sized) free-standing form factor with small thermal capacity and intriguing electronic and optical properties, thereby, ensuring high sensitivity and high speed of operation. Nevertheless, the key parameter for bolometric sensor material—the temperature coefficient of resistance (TCR)—is unacceptably low limiting the application of the carbon nanotube films. Here, we examine the plasma treatment of single-walled carbon nanotube (SWCNT) films as the effective method for the TCR enhancement. We study the effect of different plasma gases (oxygen, nitrogen, and hydrogen) on the conductivity of treated films. Also, we investigate the effect of defectiveness, length, and bundling degree of the SWCNTs on TCR. The optimized procedure allows to increase the TCR up to 1.7% K−1 by modulus at 100 K and to 0.8% K−1 at 300 K. The bolometer prototypes based on the plasma-treated SWCNT films demonstrate high sensitivity over a wide IR range (∼21 V/W), a short response time (∼1 ms), and low noise equivalent power (∼8 × 10−9 W Hz−1/2) at the temperature of 100 K.

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Elamaran, Durgadevi, Yuya Suzuki, Hiroaki Satoh, Amit Banerjee, Norihisa Hiromoto et Hiroshi Inokawa. « Performance Comparison of SOI-Based Temperature Sensors for Room-Temperature Terahertz Antenna-Coupled Bolometers : MOSFET, PN Junction Diode and Resistor ». Micromachines 11, n^o 8 (24 juillet 2020) : 718. http://dx.doi.org/10.3390/mi11080718.

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Assuming that the 0.6-μm silicon-on-insulator (SOI) complementary metal–oxide–semiconductor (CMOS) technology, different Si-based temperature sensors such as metal-oxide-semiconductor field-effect transistor (MOSFET) (n-channel and p-channel), pn-junction diode (with p-body doping and without doping), and resistors (n+ or p+ single crystalline Si and n+ polycrystalline Si) were designed and characterized for its possible use in 1-THz antenna-coupled bolometers. The use of a half-wave dipole antenna connected to the heater end was assumed, which limited the integrated temperature sensor/heater area to be 15 × 15 µm. Our main focus was to evaluate the performances of the temperature sensor/heater part, and the optical coupling between the incident light and heater via an antenna was not included in the evaluation. The electrothermal feedback (ETF) effect due to the bias current was considered in the performance estimation. A comparative analysis of various SOI bolometers revealed the largest responsivity (Rv) of 5.16 kV/W for the n-channel MOSFET bolometer although the negative ETF in MOSFET reduced the Rv. The noise measurement of the n-channel MOSFET showed the NEP of 245 pW/Hz1/2, which was more than one order of magnitude smaller than that of the n+ polycrystalline Si resistive bolometer (6.59 nW/Hz1/2). The present result suggests that the n-channel MOSFET can be a promising detector for THz applications.

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Merenkov A. V., Kim T. M., Chichkov V. I., Kalinkin S. V. et Shitov S. V. « Superconducting bolometer with high-frequency readout circuit at 400 mK ». Physics of the Solid State 64, n^o 10 (2022) : 1387. http://dx.doi.org/10.21883/pss.2022.10.54223.50hh.

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The detection of a terahertz optical signal using a bolometric detector with a planar niobium resonator loaded with a hafnium micromotor using the nonlinearity of the impedance of an electron gas at a frequency of 1.5 GHz near the critical temperature of the micromotor is demonstrated for the first time. The temperature of the electron gas was shifted by the resonator current, and the superconducting transition of the micromotor occurred under the action of a terahertz signal. The test thermodynamic signal from a thin-film Fe-Cr-Ni absorber heated in the range of 1-10 K was focused from a distance of 10 mm with an immersion lens made of sapphire onto a planar antenna matched with a micro-bridge in the range of 600-700 GHz. The measured power transmission coefficient of the bolometer was +5.5 dB with a saturation power of ~1 pW and a threshold sensitivity of the receiving system (3±1)·10-17 W/sqrt(Hz)sqrt sqrt, which is close to the theoretical values for the investigated bridge with a size of 2.5x2.5x0.08 μm. The tested detector can be used to create imaging terahertz matrices with frequency multiplexing in sorption-type cryostats. Keywords: RFTES bolometer, superconducting micro bridge, high-frequency impedance of superconductor, hafnium film, electron gas, planar resonator, frequency multiplexing, planar antenna, black body, thermodynamic noise. Keywords: RFTES bolometer, superconducting microbridge, high-frequency impedance, hafnium film, electron gas, coplanar resonator, frequency-division multiplexing, planar antenna, blackbody, noise.

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Verde, Jose C., Alberto S. Viz, Martín M. Botana, Carlos Montero-Orille et Manuel V. Ramallo. « Calculations of Some Doping Nanostructurations and Patterns Improving the Functionality of High-Temperature Superconductors for Bolometer Device Applications ». Nanomaterials 10, n^o 1 (3 janvier 2020) : 97. http://dx.doi.org/10.3390/nano10010097.

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We calculate the effects of doping nanostructuration and the patterning of thin films of high-temperature superconductors (HTS) with the aim of optimizing their functionality as sensing materials for resistive transition-edge bolometer devices (TES). We focus, in particular, on spatial variations of the carrier doping into the CuO 2 layers due to oxygen off-stoichiometry, (that induce, in turn, critical temperature variations) and explore following two major cases of such structurations: First, the random nanoscale disorder intrinsically associated to doping levels that do not maximize the superconducting critical temperature; our studies suggest that this first simple structuration already improves some of the bolometric operational parameters with respect to the conventional, nonstructured HTS materials used until now. Secondly, we consider the imposition of regular arrangements of zones with different nominal doping levels (patterning); we find that such regular patterns may improve the bolometer performance even further. We find one design that improves, with respect to nonstructured HTS materials, both the saturation power and the operating temperature width by more than one order of magnitude. It also almost doubles the response of the sensor to radiation.

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Piat, M., G. Stankowiak, E. S. Battistelli, P. de Bernardis, G. D'Alessandro, M. De Petris, L. Grandsire et al. « QUBIC IV : Performance of TES bolometers and readout electronics ». Journal of Cosmology and Astroparticle Physics 2022, n^o 04 (1 avril 2022) : 037. http://dx.doi.org/10.1088/1475-7516/2022/04/037.

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Abstract A prototype version of the Q & U bolometric interferometer for cosmology (QUBIC) underwent a campaign of testing in the laboratory at Astroparticle Physics and Cosmology laboratory in Paris (APC). The detection chain is currently made of 256 NbSi transition edge sensors (TES) cooled to 320 mK. The readout system is a 128:1 time domain multiplexing scheme based on 128 SQUIDs cooled at 1 K that are controlled and amplified by a SiGe application specific integrated circuit at 40 K. We report the performance of this readout chain and the characterization of the TES. The readout system has been functionally tested and characterized in the lab and in QUBIC. The low noise amplifier demonstrated a white noise level of 0.3 nV/√Hz. Characterizations of the QUBIC detectors and readout electronics includes the measurement of I-V curves, time constant and the noise equivalent power. The QUBIC TES bolometer array has approximately 80% detectors within operational parameters. It demonstrated a thermal decoupling compatible with a phonon noise of about 5 × 10-17 W/√Hz at 410 mK critical temperature. While still limited by microphonics from the pulse tubes and noise aliasing from readout system, the instrument noise equivalent power is about 2 × 10-16 W/√Hz, enough for the demonstration of bolometric interferometry.

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Shubbar, Mustafa, et Balázs Rakos. « A Self-Adapting, Pixelized Planar Antenna Design for Infrared Frequencies ». Sensors 22, n^o 10 (12 mai 2022) : 3680. http://dx.doi.org/10.3390/s22103680.

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Infrared antennas with reconfigurable characteristics offer several advantages in the medical, military, telecommunication and energy harvesting areas, while their design and implementation is a particularly challenging task for the researchers. This paper proposes a pixel antenna, designed for mid-infrared frequencies with a bandwidth more than 25 THz, consisting of 3 × 3 square metallic planar patches. Bolometer-based switches are placed between the adjacent pixels in order to obtain the adaptable characteristics, optimized for the incoming infrared radiation. The incident wave from a certain direction will heat up the bolometers. Consequently, the conductivity of these bolometers (PTC) will be decreased, and as a result they can be considered to turn to OFF state. The simulation results suggest that the proposed structure can steer the antenna pattern toward the direction of the incident radiation in an adaptable manner, thereby considerably increasing the antenna gain. The gain of the antenna can be increased up to 2 dB with respect to the reference one, which makes it a promising structure for various applications.

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Sheikh, U. A., L. Simons, B. P. Duval, O. Février, D. Moret, A. Allegrucci, M. Bernert, F. Crisinel, T. Tersztyánszky et O. Villinger. « RADCAM—A radiation camera system combining foil bolometers, AXUV diodes, and filtered soft x-ray diodes ». Review of Scientific Instruments 93, n^o 11 (1 novembre 2022) : 113513. http://dx.doi.org/10.1063/5.0095907.

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Measurements of radiated power are critical for characterizing and optimizing tokamak performance. The RADCAM system, comprising arrays of foil bolometers, Absolute eXtreme UltraViolet (AXUV), and filtered soft x-ray diodes, has been constructed to provide improved measurements of plasma radiation on “Tokamak a Configuration Variable” (TCV). An overview of the physical geometry, electronics, and design of the system is provided. The construction of the bolometer foils together with the improved sensitivity characteristics resulting from the inclusion of an anti-reflection carbon coating are presented. The large number of lines of sight in RADCAM are shown to significantly increase the spatial resolution over the legacy system. The system calibration procedure is detailed, and the mean system sensitivity is shown to vary by less than 5% over 1000 discharges. Additionally, the methodology for cross-calibration of the AXUV diodes with the bolometer foils is presented and applied to generate high temporal resolution measurements. The RADCAM radiation camera system is a compact, versatile system that is demonstrated to provide high resolution profiles of the radiated power in TCV.

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Гунбина, А. А., М. А. Тарасов, С. А. Лемзяков, А. М. Чекушкин, Р. А. Юсупов, Д. В. Нагирная, М. А. Мансфельд et al. « Спектральный отклик матриц полуволновых и электрически малых антенн с СИНИС-болометрами ». Физика твердого тела 62, n^o 9 (2020) : 1440. http://dx.doi.org/10.21883/ftt.2020.09.49767.35h.

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Two types arrays of ring half – wave and electrically small antennas (the typical sizes of the elements correspond to 1/10 of the wavelength) of SubTHz band with integrated Superconductor – Insulator – Normal metal – Insulator-Superconductor (SINIS) bolometers have been developed, fabricated and investigated. It is necessary to make numerical modeling of the full structure and to use additional reference channels in experimental studies for improving the accuracy of the spectral response estimations of receiving arrays. In this work, three reference channels were used for normalization: a pyroelectric receiver outside the cryostat and two cold channels – a RuO2 bolometer and chain of NIS junctions as a thermometer.

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Kang, In-Ku, Y. Ashok Kumar Reddy, Young Bong Shin, Woo Young Kim et Hee Chul Lee. « Sputtering pressure dependent bolometric properties of Ni 1−x O thin films for uncooled bolometer applications ». Ceramics International 43, n^o 12 (août 2017) : 9498–504. http://dx.doi.org/10.1016/j.ceramint.2017.04.131.

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Holland, W. S., P. A. R. Ade, M. J. Griffin, I. D. Hepburn, D. G. Vickers, C. R. Cunningham, P. R. Hastings et al. « 100 mK bolometers for the submillimetre common-user bolometer array (scuba) I. Design and construction ». International Journal of Infrared and Millimeter Waves 17, n^o 4 (avril 1996) : 669–92. http://dx.doi.org/10.1007/bf02088363.

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Zakharov, Yu N., V. P. Sakhnenko, I. A. Parinov, I. P. Raevsky, M. A. Bunin, V. A. Chebanenko, M. A. Zaerko, E. I. Sitalo, A. A. Pavelko et L. I. Kiseleva. « Possibilities of the practical use of a stationary strain gradient in the interelectrode volume of unpolarized ferroceramic plates ». Journal of Advanced Dielectrics 10, n^o 01n02 (février 2020) : 2060010. http://dx.doi.org/10.1142/s2010135x20600103.

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It has been established that in plates made of hot-pressed ferroelectric ceramics PZT-19 ([Formula: see text]C), after metal electrodes from Ag are burned into opposite surfaces with different depths of mechanical damage, counter-directional stationary deformation gradients and, accordingly, internal electric displacement fields create a stationary flexoelectric effect. As a result, unpolarized ceramics below the Curie temperature become a pyroelectric, and above it become a pyroelectric bolometer. After polishing the less damaged surface and replacing the Ag (valency [Formula: see text]) electrode with Cr ([Formula: see text]) by thermal evaporation in vacuum from the intact surface, a new thermally stable polarization is created, directed from the damaged surface in the interelectrode volume. Such plates have an asymmetric dielectric hysteresis loop, retain the values of the pyroelectric effect and piezoelectric effect in the ferroelectric phase, as well as the bolometric effect in the paraelectric phase after repeated heating cycles to [Formula: see text]C and cooling to [Formula: see text].

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Tucker, G. S., J. Kim, P. Timbie, S. Ali, L. Piccirillo et C. Calderon. « Bolometric interferometry : the millimeter-wave bolometric interferometer ». New Astronomy Reviews 47, n^o 11-12 (décembre 2003) : 1173–76. http://dx.doi.org/10.1016/j.newar.2003.09.024.

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Niklaus, Frank, Adit Decharat, Christer Jansson et Göran Stemme. « Performance model for uncooled infrared bolometer arrays and performance predictions of bolometers operating at atmospheric pressure ». Infrared Physics & ; Technology 51, n^o 3 (janvier 2008) : 168–77. http://dx.doi.org/10.1016/j.infrared.2007.08.001.

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Fusetto, Samuele, Antonio Aprile, Piero Malcovati et Edoardo Bonizzoni. « Readout IC Architectures and Strategies for Uncooled Micro-Bolometers Infrared Focal Plane Arrays : A Review ». Sensors 23, n^o 5 (2 mars 2023) : 2727. http://dx.doi.org/10.3390/s23052727.

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InfraRed Focal Plane Arrays (IRFPAs) are crucial components in a wide range of applications, including night vision, thermal imaging and gas sensing. Among the various types of IRFPAs, micro-bolometer-based ones have gained significant attention due to their high sensitivity, low noise and low cost. However, their performance is heavily dependent on the readout interface, which converts the analog electrical signals provided by the micro-bolometers into digital signals for further processing and analysis. This paper briefly introduces these kinds of devices and their function, reporting and discussing a list of key parameters used to evaluate their performance; after that, the focus is shifted to the readout interface architecture with particular attention to the different strategies adopted, across the last two decades, in the design and development of the main blocks included in the readout chain.

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Runnoe, Jessie C., Michael S. Brotherton et Zhaohui Shang. « Updating quasar bolometric luminosity corrections - II. Infrared bolometric corrections ». Monthly Notices of the Royal Astronomical Society 426, n^o 4 (17 octobre 2012) : 2677–88. http://dx.doi.org/10.1111/j.1365-2966.2012.21644.x.

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Kim, Dohyeong, Daye Lee et Myungshin Im. « Bolometric luminosity estimators using infrared hydrogen lines for dust obscured active galactic nuclei ». Monthly Notices of the Royal Astronomical Society 509, n^o 1 (25 octobre 2021) : 1147–59. http://dx.doi.org/10.1093/mnras/stab3072.

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ABSTRACT Bolometric luminosity is an important quantity that tells us the radiative energy output of an active galactic nucleus (AGN). A common way to estimate bolometric luminosity is to use ultraviolet (UV) or optical luminosities as its proxies, but the UV- or optical-based-bolometric luminosity estimators can be easily affected by dust extinction. In this study, we present new methods for estimating bolometric luminosities using infrared (IR) hydrogen Paschen and Brackett line luminosities to alleviate the dust extinction effects. We show that there exist tight correlations between the bolometric luminosities and the IR hydrogen line luminosities, and present the IR hydrogen line-based-bolometric luminosity estimators. As an example, we apply the relation to dust obscured red AGNs, confirming previous results that red AGNs have higher Eddington rations than unobscured AGNs. The new bolometric luminosity estimator will be useful for studying obscured AGNs (e.g. red AGNs, Compton thick AGNs, and Type 2 AGNs), during the coming era of sensitive near-infrared (NIR) and mid-infrared (MIR) missions, such as the James Webb Space Telescope.

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Duras, F., A. Bongiorno, F. Ricci, E. Piconcelli, F. Shankar, E. Lusso, S. Bianchi et al. « Universal bolometric corrections for active galactic nuclei over seven luminosity decades ». Astronomy & ; Astrophysics 636 (avril 2020) : A73. http://dx.doi.org/10.1051/0004-6361/201936817.

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Context. The AGN bolometric correction is a key element for understanding black hole (BH) demographics and computing accurate BH accretion histories from AGN luminosities. However, current estimates still differ from each other by up to a factor of two to three, and rely on extrapolations at the lowest and highest luminosities. Aims. Here we revisit this fundamental question by presenting general hard X-ray (KX) and optical (KO) bolometric corrections, computed by combining several AGN samples spanning the widest (about 7 dex) luminosity range ever used for this type of studies. Methods. We analysed a total of ∼1000 type 1 and type 2 AGN for which we performed a dedicated SED-fitting. Results. We provide a bolometric correction separately for type 1 and type 2 AGN; the two bolometric corrections agree in the overlapping luminosity range. Based on this we computed for the first time a universal bolometric correction for the whole AGN sample (both type 1 and type 2). We found that KX is fairly constant at log(LBOL/L⊙) < 11, while it increases up to about one order of magnitude at log(LBOL/L⊙) ∼ 14.5. A similar increasing trend has been observed when its dependence on either the Eddington ratio or the BH mass is considered, while no dependence on redshift up to z ∼ 3.5 has been found. In contrast, the optical bolometric correction appears to be fairly constant (i.e. KO ∼ 5) regardless of the independent variable. We also verified that our bolometric corrections correctly predict the AGN bolometric luminosity functions. According to this analysis, our bolometric corrections can be applied to the whole AGN population in a wide range of luminosity and redshift.

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Spielman, R. B., C. Deeney, D. L. Fehl, D. L. Hanson, N. R. Keltner, J. S. McGurn et J. L. McKenney. « Fast resistive bolometry ». Review of Scientific Instruments 70, n^o 1 (janvier 1999) : 651–55. http://dx.doi.org/10.1063/1.1149488.

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Ekstrom, H., B. Karasik, E. Kollberg et S. K. Yngvesson. « Superconducting bolometric mixers ». IEEE Microwave and Guided Wave Letters 4, n^o 7 (juillet 1994) : 253–55. http://dx.doi.org/10.1109/75.298257.

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Mitko, S. V., A. Yu Oudalov, Yu B. Udalov, P. J. M. Peters et K. J. Boller. « Thermo reflectance bolometry ». Review of Scientific Instruments 76, n^o 1 (janvier 2005) : 013101. http://dx.doi.org/10.1063/1.1823655.

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Pennell, Alison, Jessie C. Runnoe et M. S. Brotherton. « Updating quasar bolometric luminosity corrections – III. [O iii] bolometric corrections ». Monthly Notices of the Royal Astronomical Society 468, n^o 2 (7 mars 2017) : 1433–41. http://dx.doi.org/10.1093/mnras/stx556.

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Pritchard, T. A., et P. W. A. Roming. « Early Time Bolometric Light Curves of Type-II Supernovae Observed by Swift ». Proceedings of the International Astronomical Union 7, S279 (avril 2011) : 383–84. http://dx.doi.org/10.1017/s1743921312013452.

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AbstractWe present early time (~0-50 days) bolometric light curves of UV-bright Core Collapse Supernovae observed with the Swift UV/Optical Telescope. We also generate pseudo-bolometric light curves from Swift UV and optical data and examine these by subtype as well as the observed and interpolated UV and IR flux contributions by epoch and bolometric corrections at early times from UV data.

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Davis, J., A. J. Booth, M. J. Ireland, A. P. Jacob, J. R. North, S. M. Owens, J. G. Robertson, W. J. Tango et P. G. Tuthill. « The Emergent Flux and Effective Temperature of δ Canis Majoris ». Publications of the Astronomical Society of Australia 24, n^o 3 (2007) : 151–58. http://dx.doi.org/10.1071/as07017.

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AbstractNew angular diameter determinations for the bright southern F8 supergiant δ CMa enable the bolometric emergent flux and effective temperature of the star to be determined with improved accuracy. The spectral flux distribution and bolometric flux have been determined from published photometry and spectrophotometry and combined with the angular diameter to derive the bolometric emergent flux ℱ = (6.50 ± 0.24) × 107 Wm−2 and the effective temperature Teff = 5818 ± 53 K. The new value for the effective temperature is compared with previous interferometric and infrared flux method determinations. The accuracy of the effective temperature is now limited by the uncertainty in the bolometric flux rather than by the uncertainty in the angular diameter.

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Eker, Z., V. Bakış, F. Soydugan et S. Bilir. « On the zero point constant of the bolometric correction scale ». Monthly Notices of the Royal Astronomical Society 503, n^o 3 (15 mars 2021) : 4231–41. http://dx.doi.org/10.1093/mnras/stab684.

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ABSTRACT Arbitrariness attributed to the zero-point constant of the V-band bolometric corrections (BCV) and its relation to ‘bolometric magnitude of a star ought to be brighter than its visual magnitude’ and ‘bolometric corrections must always be negative’ was investigated. The falsehood of the second assertion became noticeable to us after IAU 2015 General Assembly Resolution B2, where the zero-point constant of bolometric magnitude scale was decided to have a definite value CBol(W) = 71.197 425 ... . Since the zero-point constant of the BCV scale could be written as C2 = CBol − CV, where CV is the zero-point constant of the visual magnitudes in the basic definition BCV = MBol − MV = mbol − mV, and CBol > CV, the zero-point constant (C2) of the BCV scale cannot be arbitrary anymore; rather, it must be a definite positive number obtained from the two definite positive numbers. The two conditions C2 > 0 and 0 < BCV < C2 are also sufficient for LV < L, a similar case to negative BCV numbers, which means that ‘bolometric corrections are not always negative’. In sum it becomes apparent that the first assertion is misleading causing one to understand bolometric corrections must always be negative, which is not necessarily true.

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Alessandrello, A., C. Brofferio, D. V. Camin, O. Cremonesi, E. Fiorini, A. Giuliani, G. Pessina et E. Previtali. « Bolometers ». Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment 289, n^o 3 (avril 1990) : 504–11. http://dx.doi.org/10.1016/0168-9002(90)91523-e.

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Mauri, Luca. « The discrete vacuum packaging of IR-microbolometers ». Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2015, DPC (1 janvier 2015) : 001123–39. http://dx.doi.org/10.4071/2015dpc-tp64.

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Packaging of Micro Electro Mechanical Systems (MEMS) requires technical challenges to be solved and overcome when stringent vacuum and hermetic sealing is required. This is typical for a wide class of devices, such as inertial sensors, MEMS atomic clocks, IR micro-bolometers, where such conditions need to be achieved to provide the performance stability during the lifetime of the devices. The most challenging vacuum requirements are related to micro-bolometers, since good vacuum level is needed for thermal insulation. Typical target pressure is ≈ 10-3 – 10-4 mbar. Vacuum hermetic packaging can be successfully achieved by dedicated getter film integration, key technology for vacuum requirements, in combination with a specific sealing process and choice of vacuum compatible materials. The discrete packaging of the device requires the attachment of the sensing element into a ceramic package, like LCC. Typically, adhesives are used as die attach material. From the vacuum point of view, adhesives are not ideal candidates and therefore the compatibility with stringent vacuum requirements is not always guaranteed. Preliminary outgassing tests on these components are recommended to select appropriate materials. Thermal treatment of components is another key point for vacuum sealing, since specific degassing treatments before and during sealing can effectively reduce the amount of gas inside the volume of the device. The getter film integration is mandatory in such kind of devices because of the stringent vacuum requirements. SAES' proprietary technology is fully compliant with micro-bolometer manufacturing and the optimization of the getter activation step, during the bonding process, enables the functionality of the device along its lifetime. Moreover, capabilities of performing residual gas analyses and leak rate measurements of sealed devices are fundamental for quality control of vacuum sealing as well as for analyses and prediction of device lifetime.

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Masini, Alberto, Annalisa Celotti et Samuele Campitiello. « Toward measuring the spin of obscured supermassive black holes ». Astronomy & ; Astrophysics 658 (février 2022) : A68. http://dx.doi.org/10.1051/0004-6361/202142451.

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Context. Mass and spin are two fundamental properties of astrophysical black holes. While some established indirect methods are adopted to measure both these properties of active galactic nuclei (AGN) when viewed relatively face-on, very few suggested methods exist to measure these properties when AGN are highly inclined and potentially obscured by large amounts of gas. Aims. In this context we explore the accuracy and performance of a recently proposed method to estimate the spin of AGN by fitting the accretion disk spectral energy distribution, when adapted for highly inclined and obscured systems, and in particular to a sample of six local water megamasers. For these sources the accretion rate and inclination angle are both known, allowing us to rely only on the AGN bolometric luminosity to infer their spin. Methods. Using the bolometric luminosity as a proxy for the accretion disk peak luminosity, we derived the expected bolometric luminosity as a function of spin. Then, we measured the bolometric luminosity of each source through X-ray spectroscopy, and compared it with the expected value to constrain the spin of the AGN. Results. The quality of the constraints depend critically on the accuracy of the measured bolometric luminosity, which is difficult to estimate in heavily obscured systems. Three out of six sources do not show consistency between the expected and measured bolometric luminosities, while the other three (four, when considering the [OIII] line as tracer of the bolometric luminosity) are formally consistent with high spin values. Conclusions. Our results suggest that this method, although promising (and possibly considered as a future calibrator for other methods) needs better observational data and further theoretical modeling to be successfully applied to obscured AGN and to infer robust results.

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Charlassier, R., E. F. Bunn, J. Ch Hamilton, J. Kaplan et S. Malu. « Bandwidth in bolometric interferometry ». Astronomy and Astrophysics 514 (mai 2010) : A37. http://dx.doi.org/10.1051/0004-6361/200913446.

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Cabrera, Blas, Lawrence M. Krauss et Frank Wilczek. « Bolometric detection of neutrinos ». Physical Review Letters 55, n^o 1 (1 juillet 1985) : 25–28. http://dx.doi.org/10.1103/physrevlett.55.25.

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Magalhães, Regina, Andres Garcia-Ruiz, Hugo F. Martins, João Pereira, Walter Margulis, Sonia Martin-Lopez et Miguel Gonzalez-Herraez. « Fiber-based distributed bolometry ». Optics Express 27, n^o 4 (6 février 2019) : 4317. http://dx.doi.org/10.1364/oe.27.004317.

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