5 research outputs found
Calorimeters for the FCC-hh
The future proton-proton collider (FCC-hh) will deliver collisions at a
center of mass energy up to TeV at an unprecedented
instantaneous luminosity of cms, resulting in
extremely challenging radiation and luminosity conditions. By delivering an
integrated luminosity of few tens of ab, the FCC-hh will provide an
unrivalled discovery potential for new physics. Requiring high sensitivity for
resonant searches at masses up to tens of TeV imposes strong constraints on the
design of the calorimeters. Resonant searches in final states containing jets,
taus and electrons require both excellent energy resolution at multi-TeV
energies as well as outstanding ability to resolve highly collimated decay
products resulting from extreme boosts. In addition, the FCC-hh provides the
unique opportunity to precisely measure the Higgs self-coupling in the
di-photon and b-jets channel. Excellent photon and jet energy resolution at low
energies as well as excellent angular resolution for pion background rejection
are required in this challenging environment. This report describes the
calorimeter studies for a multi-purpose detector at the FCC-hh. The calorimeter
active components consist of Liquid Argon, scintillating plastic tiles and
Monolithic Active Pixel Sensors technologies. The technological choices, design
considerations and achieved performances in full Geant4 simulations are
discussed and presented. The simulation studies are focused on the evaluation
of the concepts. Standalone studies under laboratory conditions as well as
first tests in realistic FCC-hh environment, including pileup rejection
capabilities by making use of fast signals and high granularity, have been
performed. These studies have been performed within the context of the
preparation of the FCC conceptual design reports (CDRs)
The scientific payload of the Ultraviolet Transient Astronomy Satellite (ULTRASAT)
The Ultraviolet Transient Astronomy Satellite (ULTRASAT) is a space-borne
near UV telescope with an unprecedented large field of view (200 sq. deg.). The
mission, led by the Weizmann Institute of Science and the Israel Space Agency
in collaboration with DESY (Helmholtz association, Germany) and NASA (USA), is
fully funded and expected to be launched to a geostationary transfer orbit in
Q2/3 of 2025. With a grasp 300 times larger than GALEX, the most sensitive UV
satellite to date, ULTRASAT will revolutionize our understanding of the hot
transient universe, as well as of flaring galactic sources. We describe the
mission payload, the optical design and the choice of materials allowing us to
achieve a point spread function of ~10arcsec across the FoV, and the detector
assembly. We detail the mitigation techniques implemented to suppress
out-of-band flux and reduce stray light, detector properties including measured
quantum efficiency of scout (prototype) detectors, and expected performance
(limiting magnitude) for various objects.Comment: Presented in the SPIE Astronomical Telescopes + Instrumentation 202
Light response study of FCC-hh plastic-scintillator tiles with SiPM readout
In this study light yield measurements of scintillating plastic tiles for cosmic muons were preformed. The setup is comprised of plastic-scintillator tiles, wavelengthshifting fibers and Silicon photomultipliers (SiPMs). The measurement setups are designed to represent the conditions at the first and last layer of the FCC-hh hadronic calorimeter as proposed in [1]. The key SiPM parameters, gain and dark count rate, were measured using a full pulse-height spectrum analysis. Optimization tests concerning the wrapping material of the plastic-scintillator tiles were performed, whereby the maximum measured light yield is 7.61(+0.38 -0.23) number-of-photoelectrons per Minimum Ionizing Particle (Npe/MIP)
Sensor characterization for the ULTRASAT space telescope
The Ultraviolet Transient Astronomical Satellite (ULTRASAT) is a scientific space mission carrying an astronomical telescope. The mission is led by the Weizmann Institute of Science (WIS) in Israel and the Israel Space Agency (ISA), while the camera in the focal plane is designed and built by Deutsches Elektronen Synchrotron (DESY) in Germany. Two key science goals of the mission are the detection of counterparts to gravitational wave sources and supernovae. The launch to geostationary orbit is planned for 2024. The telescope with a field-of-view of ≈ 200 deg, is optimized to work in the near-ultraviolet (NUV) band between 220 and 280 nm. The focal plane array is composed of four 22:4-megapixel, backside-illuminated (BSI) CMOS sensors with a total active area of 90 x 90mm. Prior to sensor production, smaller test sensors have been tested to support critical design decisions for the final flight sensor. These test sensors share the design of epitaxial layer and antireflective coatings with the flight sensors. Here, we present a characterization of these test sensors. Dark current and read noise are characterized as a function of the device temperature. A temperature-independent noise level is attributed to on-die infrared emission and the read-out electronics' self-heating. We utilize a high-precision photometric calibration setup to obtain the test sensors' quantum efficiency relative to PTB/NIST-calibrated transfer standards (220-1100 nm), the quantum yield for >300 nm, the non-linearity of the system, and the conversion gain. The uncertainties are discussed in the context of the newest results on the setup's performance parameters. From the three ARC options Tstd, T1 and T2, the last assists the out-of-band rejection and peaks in the mid of the ULTRASAT operational waveband. We recommend ARC option T2 for the final ULTRASAT UV sensor
Design of the ULTRASAT UV camera
The Ultraviolet Transient Astronomical Satellite (ULTRASAT) is a scientific UV space telescope that will operate in geostationary orbit. The mission, targeted to launch in 2024, is led by the Weizmann Institute of Science (WIS) in Israel and the Israel Space Agency (ISA). Deutsches Elektronen Synchrotron (DESY) in Germany is tasked with the development of the UV-sensitive camera at the heart of the telescope. The camera's total sensitive area of ≈90mm x 90mm is built up by four back-side illuminated CMOS sensors, which image a field of view of ≈200 deg2. Each sensor has 22:4 megapixels. The Schmidt design of the telescope locates the detector inside the optical path, limiting the overall size of the assembly. As a result, the readout electronics is located in a remote unit outside the telescope. The short focal length of the telescope requires an accurate positioning of the sensors within ±50 μm along the optical axis, with a flatness of ±10 μm. While the telescope will be at around 295K during operations, the sensors are required to be cooled to 200K for dark current reduction. At the same time, the ability to heat the sensors to 343K is required for decontamination. In this paper, we present the preliminary design of the UV sensitive ULTRASAT camera