arXiv subjects

V. Peskov

Publications and source records attributed to V. Peskov.

At least 55 records · Page 3Linked to original sources

arXiv2007

Development of innovative micropattern gaseous detectors with resistive electrodes and first results of their applications

The paper summarizes our latest progress in the development of newly introduced micro pattern gaseous detectors with resistive electrodes. These resistive electrodes protect the detector and the front-end electronics in case of occasional discharges and thus make the detectors very robust and reliable in operation. As an example, we describe in greater detail a new recently developed GEM-like detector, fully spark-protected with electrodes made of resistive kapton. We discovered that all resistive layers used in these studies (including kapton), that are coated with photosensitive layers, such as CsI, can be used as efficient photo cathodes for detectors operating in a pulse counting mode. We describe the first applications of such detectors combined with CsI or SbCs photo cathodes for the detection of UV photons at room and cryogenic temperatures.

physics.ins-det↗

arXiv2007

The current progress of the ALICE Ring Imaging Cherenkov Detector

Recently, the last two modules (out of seven) of the ALICE High Momentum Particle Identification detector (HMPID) were assembled and tested. The full detector, after a pre-commissioning phase, has been installed in the experimental area, inside the ALICE solenoid, at the end of September 2006. In this paper we review the status of the ALICE/HMPID project and we present a summary of the series production of the CsI photo-cathodes. We describe the key features of the production procedure which ensures high quality photo-cathodes as well as the results of the quality assessment performed by means of a specially developed 2D scanner system able to produce a detailed map of the CsI photo-current over the entire photo-cathode surface. Finally we present our recent R&D efforts toward the development of a novel generation of imaging Cherenkov detectors with the aim to identify, in heavy ions collisions, hadrons up to 30 GeV/c.

physics.ins-det↗

arXiv2007

First Tests of Thick GEMs with Electrodes Made of a Resistive Kapton

We have developed a new design of a GEM-like detector with single-layer electrodes made of a resistive kapton. This detector can operate at gains close to 10E5 even in pure Ar and Ne and if transited to discharges at higher gains they, due to the high resistivity of electrodes, do not damage either the detector or the front-end electronics. Gains ~ 106 can be achieved in a cascaded mode of the operation. The detector can operate without gain degradation at counting rates up to 10E4Hz/cm2 and thus it could be very useful in many applications which require safe high gain operation, for example in RICH, TPCs, calorimetric.

physics.plasm-ph↗

arXiv2006

A New GEM-like Imaging Detector with Electrodes Coated with Resistive Layers

We have developed and tested several prototypes of GEM-like detectors with electrodes coated with resistive layers: CuO or CrO. These detectors can operate stably at gains close to 10E5 and they are very robust. We discovered that the cathodes of these detectors could be coated by CsI layers and in such a way the detectors gain high efficiency for the UV photons. We also demonstrated that such detectors can operate stably in the cascade mode and high overall gains (~10E6) are reachable. This opens applications in several areas, for example in RICH or in noble liquid TPCs. Results from the first applications of these devices for UV photon detection at room and cryogenic temperatures are given.

physics.ins-det↗

arXiv2006

The first applications of novel gaseous detectors for UV visualization

We have demonstrated experimentally that recently developed gaseous detectors combined with solid or gaseous photo-cathodes have exceptionally low noise and high quantum efficiency for UV photons while being solar blind. For this reason they can be used for the detection of weak UV sources in daylight conditions. These detectors are extremely robust, can operate in poor gas conditions and are cheap. We present the first results of their applications to hyper-spectroscopy and flame detection in daylight conditions.

physics.ins-det↗

arXiv2006

The Development of Sealed UV Sensitive Gaseous Detectors and their Applications

We have developed commercial prototypes of sealed gaseous detectors combined with CsI photocathodes and/or filled with photosensitive vapors. The rirst results of application of these devices for the detection of flames in daylight conditions and for the detection of scintillation lights from noble liquids will be presented. The main conclusion from our studies is that for some applications the sealed UV sensitive gaseous detectors have superior performance (higher practical quantum efficiency and better signal to noise ratio) than existing commercial UV sensitive detectors. Additionally, they are much cheaper.

physics.ins-det↗

arXiv2006

A Novel UV Photon Detector with Resistive Electrodes

In this study we present first results from a new detector of UV photons: a thick gaseous electron multiplier (GEM) with resistive electrodes, combined with CsI or CsTe/CsI photocathodes. The hole type structure considerably suppresses the photon and ion feedback, whereas the resistive electrodes protect the detector and the readout electronics from damage by any eventual discharges. This device reaches higher gains than a previously developed photosensitive RPC and could be used not only for the imaging of UV sources, flames or Cherenkov light, for example, but also for the detection of X-rays and charged particles.

physics.ins-det↗

arXiv2005

A Study of the Operation of Especially Designed Photosensitive Gaseous Detectors at Cryogenic Temperatures

In some experiments and applications there is need for large-area photosensitive detectors to operate at cryogenic temperatures. Nowadays, vacuum PMs are usually used for this purpose. We have developed special designs of planar photosensitive gaseous detectors able to operate at cryogenic temperatures. Such detectors are much cheaper PMs and are almost insensitive to magnetic fields. Results of systematic measurements of their quantum efficiencies, the maximum achievable gains and long-term stabilities will be presented. The successful operation of these detectors open realistic possibilities in replacing PMs by photosensitive gaseous detectors in some applications dealing with cryogenic liquids; for example in experiments using noble liquid TPCs or noble liquid scintillating calorimeters.

physics.ins-det↗

arXiv2005

Advanced Photodetectors for Hyperspectroscopy and Other Applications

Hyperspectroscopy is a new method of surface image taking, providing simultaneously high position and spectral resolutions which allow one to make some conclusions about chemical compositions of the surfaces. We are now studying applications of the hyperspctroscopic technique to be used for medicine. This may allow one to develop early diagnostics of some illnesses, as for example, skin cancer. For image taking advanced MCPs are currently used, sensitive in the spectral interval of 450-850 nm. One of the aims of this work is to extend the hyperspectrocpic method to the UV region of spectra: 185-280 nm. For this we have developed and successfully tested innovative 1D and 2D UV sealed photosensitive gaseous detectors with resistive electrodes. These detectors are superior MCPs due to the very low rate of noise pulses and thus due to the high signal to noise ratio. Other important features of these detectors are that they have excellent position resolutions - 30 micron in digital form, are vibration stable and are spark protected. The first results from the application of these detectors for spectroscopy, hyperspectroscopy and the flame detection are presented.

physics.ins-det↗

arXiv2005

Photosensitive Gaseous Detectors for Cryogenic Temperature Applications

There are several proposals and projects today for building LXe Time Projection Chambers (TPCs) for dark matter search. An important element of these TPCs are the photomultipliers operating either inside LXe or in vapors above the liquid. We have recently demonstrated that photosensitive gaseous detectors (wire type and hole-type) can operate perfectly well until temperatures of LN2. In this paper results of systematic studies of operation of the photosensitive version of these detectors (combined with reflective or semi-transparent CsI photocathodes) in the temperature interval of 300-150 K are presented. In particular, it was demonstrated that both sealed and flushed by a gas detectors could operate at a quite stable fashion in a year/time scale. Obtained results, in particular the long-term stability of photosensitive gaseous detectors, strongly indicate that they can be cheap and simple alternatives to photomultipliers or avalanche solid-state detectors in LXe TPC applications.

physics.ins-det↗

arXiv2005

Novel Single Photon Detectors for UV Imaging

There are several applications which require high position resolution UV imaging. For these applications we have developed and successfully tested a new version of a 2D UV single photon imaging detector based on a microgap RPC. The main features of such a detectors is the high position resolution - 30 micron in digital form and the high quantum efficiency (1-8% in the spectral interval of 220-140 nm). Additionally, they are spark- protected and can operate without any feedback problems at high gains, close to a streamer mode. In attempts to extend the sensitivity of RPCs to longer wavelengths we have successfully tested the operation of the first sealed parallel-plate gaseous detectors with CsTe photocathodes. Finally, the comparison with other types of photosensitive detectors is given and possible fields of applications are identified.

physics.ins-det↗

arXiv2004

A High Position Resolution X-ray Detector: an Edge on Illuminated Capillary Plate Combined with a Gas Amplification Structure

We have developed and successfully tested a prototype of a new type of high position resolution hybrid X-ray detector. It contains a thin wall lead glass capillary plate converter of X-rays combined with a microgap parallel-plate avalanche chamber filled with gas at 1 atm. The operation of these converters was studied in a wide range of X-ray energies (from 6 to 60 keV) at incident angles varying from 0-90 degree. The detection efficiency, depending on the geometry, photon energy, incident angle and the mode of operation, was between 5-30 percent in a single step mode and up to 50 percent in a multi-layered combination. Depending on the capillary geometry, the position resolution achieved was between 0.050-0.250 mm in digital form and was practically independent of the photon energy or gas mixture. The usual lead glass capillary plates operated without noticeable charging up effects at counting rates of 50 Hz/mm2, and hydrogen treated capillaries up to 10E5 Hz/mm2. The developed detector may open new possibilities for medical imaging, for example in mammography, portal imaging, radiography (including security devices), crystallography and many other applications.

physics.ins-det↗

arXiv2004

The Successful Operation of Hole-type Gaseous Detectors at Cryogenic Temperatures

We have demonstrated that hole-type gaseous detectors, GEMs and capillary plates, can operate up to 77 K. For example, a single capillary plate can operate at gains of above 10E3 in the entire temperature interval between 300 until 77 K. The same capillary plate combined with CsI photocathodes could operate perfectly well at gains (depending on gas mixtures) of 100-1000. Obtained results may open new fields of applications for capillary plates as detectors of UV light and charge particles at cryogenic temperatures: noble liquid TPCs, WIMP detectors or LXe scintillating calorimeters and cryogenic PETs.

physics.ins-det↗

arXiv2004

Micropattern Gaseous Detectors

Currently a revolution is taking place in the development of gaseous detectors of photons and particles. Parallel plate-type and wire-type detectors which dominated for years in high energy and space flight experiments are now being replaced by recently invented Micropattern gaseous detectors. We will now review the main achievements in this field and discuss the most promising directions in future developments and applications.

physics.ins-det↗

arXiv2004

Study of capillary-based gaseous detectors

We have studied gain vs. voltage characteristics and position resolutions of multistep capillary plates (two or three capillary plates operating in a cascade), as well as capillary plates operating in a mode when the main amplification occurs between plates or between the capillary plate and the readout plate (parallel plate amplification mode). Results of these studies demonstrated that in the parallel-plate amplification mode one can reach both high gains (>100000) and good position resolutions (~100 micro meter) even with a single step arrangement. It offers a compact amplification structure, which can be used in many applications. For example, in preliminary tests we succeeded to combine it with a photocathode and use it as a position sensitive gaseous photomultiplier. CsI coated capillary plates could also be used as a high position resolution and high rate X-ray converter.

physics.ins-det↗

arXiv2004

The development of gaseous detectors with solid photocathodes for low temperature

There are several applications and fundamental research areas which require the detection of VUV light at cryogenic temperatures. For these applications we have developed and successfully tested special designs of gaseous detectors with solid photocathodes able to operate at low temperatures: sealed gaseous detectors with MgF2 windows and windowless detectors. We have experimentally demonstrated, that both primary and secondary (due to the avalanche multiplication inside liquids) scintillation lights could be recorded by photosensitive gaseous detectors. The results of this work may allow one to significantly improve the operation of some noble liquid gas TPCs.

physics.ins-det↗

arXiv2002

The Development and Study of High-Position Resolution (50 micron) RPCs for Imaging X-rays and UV photons

Nowadays, commonly used Resistive Plate Chambers (RPCs) have counting rate capabilities of ~10E4Hz/cm2 and position resolutions of ~1cm. We have developed small prototypes of RPCs (5x5 and 10x10cm2) having rate capabilities of up to 10E7Hz/cm2 and position resolutions of 50 micron("on line" without application of any treatment method like "center of gravity"). The breakthrough in achieving extraordinary rate and position resolutions was only possible after solving several serious problems: RPC cleaning and assembling technology, aging, spurious pulses and afterpulses, discharges in the amplification gap and along the spacers. High-rate, high-position resolution RPCs can find a wide range of applications in many different fields, for example in medical imaging. RPCs with the cathodes coated by CsI photosensitive layer can detect ultraviolet photons with a position resolution that is better than ~30 micron. Such detectors can also be used in many applications, for example in the focal plane of high resolution vacuum spectrographs or as image scanners.

physics.ins-det↗

arXiv2002

Beyond the RICH: Innovative Photosensitive Gaseous Detectors for new Fields of Applications

We have developed and successfully used several innovative designs of detectors with solid photocathodes. The main advantage of these detectors is that rather high gains (>10E4) can be achieved in a single multiplication step. This is possible by, for instance, exploiting the secondary electron multiplication and limiting the energy of the steamers by distributed resistivity. The single step approach also allows a very good position resolution to be achieved in some devices: 50 micron on line without applying any treatment method (like center of gravity). The main focus of our report is new fields of applications for these detectors and the optimization of their designs for such purposes.

physics.ins-det↗