Physics beyond the Standard Model predicts the possible existence of new particles that can be searched at the low energy frontier in the sub-eV range. The OSQAR photon regeneration experiment looks ...for "Light Shining through a Wall" from the quantum oscillation of optical photons into "Weakly Interacting Sub-eV Particles", such as axion or Axion-Like Particles (ALPs), in a 9 T transverse magnetic field over the unprecedented length of 2 × 14.3 m. In 2014, this experiment has been run with an outstanding sensitivity, using an 18.5 W continuous wave laser emitting in the green at the single wavelength of 532 nm. No regenerated photons have been detected after the wall, pushing the limits for the existence of axions and ALPs down to an unprecedented level for such a type of laboratory experiment. The di-photon couplings of possible pseudoscalar and scalar ALPs can be constrained in the nearly massless limit to be less than 3.5·10 −8 GeV −1 and 3.2·10 −8 GeV −1 , respectively, at 95% Confidence Level.
After pioneering gaseous detectors of single photon for RICH applications using CsI solid state photocathodes in MWPCs within the RD26 collaboration and by the constructions for the RICH detector of ...the COMPASS experiment at CERN SPS, in 2016 we have upgraded COMPASS RICH by novel gaseous photon detectors based on MPGD technology. Four novel photon detectors, covering a total active area of 1.5m2 have been installed in order to cope with the challenging efficiency and stability requirements of the COMPASS physics programme. They are the first application in an experiment of MPGD-based single photon detectors. All aspects of the upgrade are presented, including engineering, mass production, quality assessment and performance.
Perspectives for further developments in the field of gaseous single photon detectors are also presented.
Recent theoretical and experimental studies highlight the possibility of new fundamental particle physics beyond the Standard Model that can be probed by sub-eV energy experiments. The OSQAR photon ...regeneration experiment looks for “Light Shining through a Wall” from the quantum oscillation of optical photons into “Weakly Interacting Sub-eV Particles”, like axion or axion-like particles (ALPs), in a 9 T transverse magnetic field over the unprecedented length of
2
×
14.3
m. No excess of events has been detected over the background. The di-photon couplings of possible new light scalar and pseudo-scalar particles can be constrained in the massless limit to be less than
8.0
×
10
-
8
GeV
-
1
. These results are very close to the most stringent laboratory constraints obtained for the coupling of ALPs to two photons. Plans for further improving the sensitivity of the OSQAR experiment are presented.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In 2016 we have upgraded the COMPASS RICH by novel gaseous photon detectors based on MPGD technology. Four new photon detectors, covering a total active area of 1.5
m
2
, have been installed in order ...to cope with the challenging efficiency and stability requirements of the COMPASS physics programme. The new detector architecture consists in a hybrid MPGD combination: two layers of THGEMs, the first of which also acts as a reflective photocathode thanks to CsI coating, are coupled to a bulk Micromegas on a pad-segmented anode. These detectors are the first application in an experiment of MPGD-based single photon detectors. Presently, we are further developing the MPGD-based PDs to make them adequate for a setup at the future EIC collider. All aspects of the COMPASS RICH-1 Photon Detectors upgrade are presented: R&D, engineering, mass production, QA and performance; the on-going development for collider application is also presented.
We report about the development status of large area gaseous single photon detectors based on a novel hybrid concept for RICH applications.
The hybrid concept combines Thick Gaseous Electron ...Multipliers (THGEMs) coupled to CsI, working as a photon sensitive pre-amplification stage, and Micromegas, as a multiplication stage. The most recent achievements within the research and development programme consist in the assembly and study of 300×300mm2 hybrid photon detectors, the optimization of front-end electronics, and engineering towards large area detectors. Hybrid detectors with an active area of 300×300mm2 have been successfully operated in laboratory conditions and at a CERN PS T10 test beam, achieving effective gains in the order of 105 and good time resolution (σ=7ns); APV25 front-end chips have been coupled to the detector resulting in noise levels lower than 1000 electrons; the production and characterization of 300×600mm2 THGEMs is ongoing.
A set of hybrid detectors with 600×600mm2 active area is envisaged to upgrade COMPASS RICH-1 at CERN in 2016.
•The hybrid detector is a novel concept for large area gaseous photon detectors.•The hybrid concept combines Thick Gaseous Electron Multipliers and Micromegas.•The COMPASS RICH-1 upgrade will adopt hybrid detectors to replace the existing MWPCs
We are developing large size THick GEM (THGEM)-based detectors of single photons, mainly meant for Cherenkov imaging applications. The R&D programme includes the complete characterisation of the ...THGEM electron multipliers, the study of the aspects related to the detection of single photons and the engineering towards large size detector prototypes. Our most recent achievements include dedicated studies concerning the ion backflow to the photocathode; relevant progress in the engineering aspects, in particularly related to the production of large-size THGEMs, where the strict correlation between the local gain-value and the local thickness-value has been demonstrated and a 300300 mm super(2) active area detector has been successfully operated at the CERN PS T10 test beam; the introduction of a new hybrid detector architecture, offering promising performance, which is formed by a THGEM layer which acts both as photocathode and pre-amplification device, followed by a MICROMEGAS (MM) multiplication stage. We report about the general status of the R&D programme and, in detail, about the recent progress.
THGEM-based photon detectors for the upgrade of COMPASS RICH-1 Alexeev, M.; Birsa, R.; Bradamante, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2013, Letnik:
732
Journal Article
Recenzirano
Odprti dostop
New Cherenkov photon detectors are being developed for the upgrade of COMPASS RICH-1. The detectors are based on THGEMs, arranged in a three layer architecture, with a CsI film on the first layer ...acting as a reflective photocathode. The response of THGEMs with various geometries under different conditions has been studied and photon detector prototypes have been built, tested in laboratory and operated during test beam runs providing a typical gain of 105 and a time resolution of better than 10ns. A photon detector prototype with 300×300mm2 active area, operated at the CERN PS T10 test beam in November 2012, has confirmed the validity of this novel technology and has allowed further studies of the detector response.
•The COMPASS THGEM R&D team has performed systematic studies and parameter optimization for THGEMs to be used in RICH applications.•A triple-THGEM photon detector with 300×300mm2 active area has been successfully tested at the CERN PS T10 test-beam.•A photon detector prototype based on coupling THGEM and Micromegas has provided encouraging results in laboratory tests.•For the upgrade of COMPASS RICH-1 a set of THGEM-based photon detectors will be produced.
COMPASS is a fixed target experiment at CERN SPS aimed to study hadron structure and spectroscopy. Hadron identification in the momentum range between 3 and 55 GeV/c is provided by a large gaseous ...Ring Imaging Cherenkov Counter, RICH-1. To cope with the challenges imposed by the new physics program of COMPASS, RICH-1 has been upgraded by replacing four MWPC-based photon detectors with newly developed MPGD-based photon detectors. The architecture of the novel detectors is a hybrid combination of two layers of THGEMs and a Micromegas. The top of the first THGEM is coated with CsI acting as a reflective photo-cathode. The anode is segmented in pads capacitively coupled to the APV-25 based readout. The new hybrid detectors have been commissioned during the 2016 COMPASS data taking and stably operated during the 2017 run. In this paper design, construction, operation and performance aspects of the novel photon detectors for COMPASS RICH-1 are discussed.
THGEM based photon detector for Cherenkov imaging applications Alexeev, M.; Birsa, R.; Bradamante, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2010, Letnik:
617, Številka:
1
Journal Article
Recenzirano
We are developing a single photon detector for Cherenkov imaging counters. This detector is based on the use of THGEM electron multipliers in a multilayer design. The major goals of our project are ...ion feedback suppression down to a few per cent, large gain, fast response, insensitivity to magnetic fields, and a large detector size.
We report about the project status and perspectives. In particular, we present a systematic study of the THGEM response as a function of geometrical parameters, production techniques and the gas mixture composition. The first figures obtained from measuring the response of a CsI coated THGEM to single photons are presented.
After pioneering gaseous detectors of single photon for RICH applications using CsI solid state photocathodes in MWPCs within the RD26 collaboration and by the constructions for the RICH detector of ...the COMPASS experiment at CERN SPS, in 2016 we have upgraded COMPASS RICH by novel gaseous photon detectors based on MPGD technology. Four novel photon detectors, covering a total active area of 1.5 m2, have been installed in order to cope with the challenging effciency and stability requirements of the COMPASS physics programme. They are the first application in an experiment of MPGD-based single photon detectors. All aspects of the upgrade are presented, including engineering, mass production, quality assessment and performance. Perspectives for further developments in the field of gaseous single photon detectors are also indicated.
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