Characteristics of a vacuum-type microcalorimeter for synchrotron-radiation measurements (original) (raw)

Development of a microcalorimeter for measuring absolute intensity of synchrotron radiation

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1991

A total absorption calorimeter was developed to measure the absolute intensity of monoenergetic X-ray beams from 10 keV to 70 keV of synchrotron radiation. Experiments with synchrotron radiation have demonstrated that the heat power above about 1 +W due to monoenergetic synchrotron radiation is measured with an accuracy of about 1%.

Multiplexed microcalorimeter arrays for precision measurements from microwave to gamma-ray wavelengths

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2007

Cryogenic microcalorimeters are a promising technology for ultrasensitive measurements of electromagnetic radiation from microwave to gamma-ray wavelengths. Cryogenic microcalorimeters derive their exquisite sensitivity from the minimal thermal noise at typical operating temperatures near 0.1 K. The core technology of the microcalorimeters under development at NIST is independent of the application wavelength: thin-film thermometers whose temperature and resistance change in response to absorbed energy. However, the absorbing structures used to couple radiation into the thermometers depend strongly on the application wavelength. Here, we describe microcalorimeter technology and its application to microwave, X-ray, and gamma-ray measurements. In particular, we present results from a 13 pixel gamma-ray microcalorimeter array with a coadded energy resolution of 51 eV FWHM at 103 keV and a single pixel with resolution of 27 eV FWHM at 103 keV. One application for gamma-ray microcalorimeters is to deconvolve the complex spectrum of a mixture of Pu isotopes near 100 keV. Published by Elsevier B.V.

Beam test of the CsI(Tl) calorimeter for the BELLE detector at the KEK-B factory

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1996

We studied the performance of a prototype electromagnetic calorimeter for the BELLE detector at the KEK proton synchrotron for an energy range of 0.2.5-3.5 GeV. The prototype consisted of an array of 6 X 5 CsI(Tl) crystals with 30 cm length (16.2 radiation lengths) and about 6 cm X 6 cm cross section. The scintillation light of each CsI(Tl) crystal was read out by two large-area PIN photodiodes and charge-sensitive preamplifiers attached at the rear face of the crystal. We measured the energy and position resolution for electrons and the e/T separation for two sets of matrix configurations: one corresponded to the center and the other to the edge of the barrel calorimeter. The overall performance measured by the test proves that the prototype calorimeter is satisfactory for the use in the BELLE detector.

Homogeneous and isotropic calorimetry for space experiments

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2013

Calorimetry plays an essential role in experiments observing high energy gamma and cosmic rays in space. The observational capabilities are mainly limited by the geometrical dimensions and the mass of the calorimeter. Since deployable mass depends on the design of the detector and the total mass of the payload, it is important to optimize the geometrical acceptance of the calorimeter for rare events, its granularity for particle identification, and its absorption depth for the measurement of the particle energy. A design of a calorimeter that could simultaneously optimize these characteristics assuming a mass limit of about 1.6 t has been studied. As a result, a homogeneous calorimeter instrumented with cesium iodide (CsI) crystals was chosen as the best compromise given the total mass constraint. The most suitable geometry found is cubic and isotropic, so as to detect particles arriving from every direction in space, thus maximizing the acceptance; granularity is obtained by filling the cubic volume with small cubic CsI crystals. The total radiation length in any direction is very large, and allows for optimal electromagnetic particle identification and energy measurement, while the interaction length is at least sufficient to allow a precise reconstruction of hadronic showers. Optimal values for the size of the crystals and spacing among them have been studied. Two prototypes have been constructed and preliminary tests with high energy ion and muon beams are reported.

Calorimetry and Cherenkov radiation

Cherenkov radiation has been frequently used to measure the energy of electromagnetic showers, for instance in lead-glass calorimeters, and now it becomes increasingly useful for hadronic calorimetry as well. A sizable fraction of cascades initiated by hadrons in an absorber is quickly transformed into g rays, giving e AE as final products. In a transparent active medium, these charged particles can radiate Cherenkov light which, detected with appropriate photosensitive devices, provides a measure of the energy of high energy showering particles. The state of the art in Cherenkov calorimetry and prospects for new types of calorimeters with high granularity and energy resolution are reviewed.

The CALICE hadron calorimeters - beam test results and new developments

Proceedings of European Physical Society Europhysics Conference on High Energy Physics — PoS(EPS-HEP 2009), 2010

We present concepts and beam test results of highly granular calorimeter prototypes optimized for the application of particle flow algorithms. A scintillator-steel hadron calorimeter using SiPMs as photodetectors (AHCAL) has been tested in electron and hadron beams at CERN and Fermilab in the energy range 1-80 GeV. More than 7600 SiPMs-the highest number ever used-performed well over the period longer than 2 years and did not show an increase of noise. The analysis of the first part of data from hadron beams leads to the energy resolution of 61%/√E which can be further improved to 49%/√E applying energy dependent weights. The data on the longitudinal and transverse shower shapes allow discriminate among hadronization models of GEANT4. Specifically QGSP_BERT and LHEP prediction were compared to the data. Further we present the concept of a Digital Hadron Calorimeter (DHCAL) with two lines of R&D following different read-out and integration approach. Both are based on glass resistive pad chambers with 1 cm 2 pad read-out, alternative amplification techniques like GEMs or MICROMEGAS are also being considered. One series of studies applies a single threshold (1bit) to the signal charges, providing digital readout with the front end part integrated on the pad board. We report on the measurements with a small scale prototype in the Fermilab test beam using muons, positrons, pions, and protons and in the laboratory using cosmic rays. An alternative approach is to use semi-digital readout electronics following a design close to the ILD detector concept. The electronics will not require active cooling and rely on power-pulsing. A small prototype was built and tested with success at the CERN PS test beam in 2008. A few GRPCs as large as 1 m 2 were built with emphasis on minimized dead zones and optimized gas flow. The GRPCs were tested with an electronics board of the same size, containing 144 64channel ASICs, representing the largest ever built chamber with embedded electronics. The results will serve as the basis for the design of the fully instrumented 1 m 3 CALICE test beam digital calorimeter.

Thermal calorimeters for high resolution X-ray spectroscopy

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 1993

Thermal detection of individual X-ray photons by small (0 .5X0 .5 mm) calorimeters has been used to achieve an energy resolution as \good as 7 .5 eV FWHM for 6 keV X-rays. Such detectors should have interesting applications in X-ray astronomy as well as laboratory spectroscopy, and they promise a high tolerance for embedded sources. Ideally, it should be possible to improve the resolution greatly by making smaller detectors or operating them at lower temperatures than the 50-100 mK currently used. However, there appear to be fairly fundamental limitations when semiconductor thermistors are used as the thermometer . When trying to achieve energy resolution of 0.1% or better, fluctuations in the thermalization efficiency of the detector must also be considered, and this places additional restrictions on suitable detector materials.

Characterization and performance of PADME’s Cherenkov-based small-angle calorimeter

Nuclear Instruments and Methods in Physics Research, 2019

The PADME experiment, at the Laboratori Nazionali di Frascati (LNF), in Italy, will search for invisible decays of the hypothetical dark photon via the process e + e − → γA , where the A escapes detection. The dark photon mass range sensitivity in a first phase will be 1 to 24 MeV. We report here on performance measurements and simulation studies of a prototype of the Small-Angle Calorimeter, a component of PADME's detector dedicated to rejecting 2and 3-gamma backgrounds. The crucial requirement is a timing resolution of less than 200 ps, which is satisfied by the choice of PbF 2 crystals and the newly released Hamamatsu R13478UV photomultiplier tubes (PMTs). We find a timing resolution of 81 ps (with double-peak separation resolution of 1.8 ns) and a single-crystal energy resolution of 10% at 550 MeV with light yield of 2.05 photo-electrons per MeV, using 100 to 400 MeV electrons at the Beam Test Facility of LNF. We also propose the investigation of a two-PMT solution coupled to a single PbF 2 crystal for higher-energy applications, which has potentially attractive features.

Recent evolutions of the microcalorimeter technique

The microcalorimeter technique continues to be the key technique for the realization of the primary power standards in the high frequency, because at the state of the art, only it allows tracing the power standards to the direct current standard, that is a SI quantity. This traceability is obtained through the determination of the effective efficiency, usually indicated by € ηe, of a power sensor as a frequency function. Even though since long time the microcalorimeter is a highly explored measurement system, the first realizations being dated from the late of 1950s, still it is possible to propose improvements that should finally increase its accuracy. Actually this one ranges realistically from 0.2% to 2%, if a significant frequency band is considered, e.g. from the radio frequencies to the millimeter waves. Better values are obtainable below 1 GHz, but beyond 18 GHz a 2% still is a challenge, particularly for power sensors in coaxial line of 3.5 mm, 2.92 mm and 2.4 mm. Waveguide ...