1. |
- Scandale, Walter, et al.
(författare)
-
Apparatus to study crystal channeling and volume reflection phenomena at the SPS H8 beamline
- 2008
-
Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 79:2
-
Tidskriftsartikel (refereegranskat)abstract
- A high performance apparatus has been designed and built by the H8-RD22 collaboration for the study of channeling and volume reflection phenomena in the interaction of 400 GeVc protons with bent silicon crystals, during the 2006 data taking in the external beamline H8 of the CERN SPS. High-quality silicon short crystals were bent by either anticlastic or quasimosaic effects. Alignment with the highly parallel (8 μrad divergence) proton beam was guaranteed through a submicroradian goniometric system equipped with both rotational and translational stages. Particle tracking was possible by a series of silicon microstrip detectors with high-resolution and a parallel plate gas chamber, triggered by various scintillating detectors located along the beamline. Experimental observation of volume reflection with 400 GeVc protons proved true with a deflection angle of (10.4±0.5) μrad with respect to the unperturbed beam, with a silicon crystal whose (111) planes were parallel to the beam. © 2008 American Institute of Physics.
|
|
2. |
|
|
3. |
- Scandale, Walter, et al.
(författare)
-
Deflection of 400GeV/c proton beam with bent silicon crystals at the CERN Super Proton Synchrotron
- 2008
-
Ingår i: Physical Review Special Topics - Accelerators and Beams. - 1098-4402. ; 11:6
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a detailed study of the deflection phenomena of a 400GeV/c proton beam impinging on a new generation of bent silicon crystals; the tests have been performed at the CERN Super Proton Synchrotron H8 beam line. Channeling and volume reflection angles are measured with an extremely precise goniometer and with high resolution silicon microstrip detectors. Volume reflection has been observed and measured for the first time at this energy, with a single-pass efficiency as large as 98%, in good agreement with the simulation results. This efficiency makes volume reflection a possible candidate for collimation with bent crystals at the CERN Large Hadron Collider. © 2008 The American Physical Society.
|
|
4. |
- Frolov, Ivan V., et al.
(författare)
-
Three new species of crustose Teloschistaceae in Siberia and the Far East
- 2021
-
Ingår i: Lichenologist. - 0024-2829. ; 53:3, s. 233-243
-
Tidskriftsartikel (refereegranskat)abstract
- Three species of the family Teloschistaceae (lichenized Ascomycota) are described as new to science from Southern and Eastern Siberia and the Far East. Corticolous Caloplaca saviczii belongs to the genus Caloplaca s. str.; it has C. cerina-like apothecia and green to grey-green, crateriform soralia with a white rim. Lendemeriella aureopruinosa is a saxicolous taxon with a thin grey thallus and small apothecia 0.3-0.6 mm in diameter, with a dark orange disc usually bearing epipsamma and often with a grey true exciple containing the pigment Cinereorufa-green. Orientophila infirma is a corticolous species with an endophloeodal thallus and small orange apothecia, 0.2-0.3 mm in diameter, usually with an inconspicuous thalline exciple. All new taxa presumably have a boreal north-eastern distribution in Asia.
|
|
5. |
- Afanasiev, Sergey V., et al.
(författare)
-
Experimental apparatus to study crystal channeling in an external SPS beamline
- 2007
-
Ingår i: Proceedings of SPIE, the International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. ; 6634
-
Tidskriftsartikel (refereegranskat)abstract
- For the new generation of high intensity hadronic machines as, for instance, LHC, halo collimation is a necessary issue for the accelerator to operate at the highest possible luminosity and to prevent the damage of superconductor magnets.1 We propose an experiment aimed to systematic study of the channeling phenomenology and of the newly observed "volume reflection" effect. This experiment will be performed for an external SPS beamline and will make use of a primary proton beam with 400 GeV/c momentum and very small (∼ 3 μrad) divergence. The advantage of a proposed experiment is precise tracking of particles that interacted with a crystal, so that to determine the single-pass efficiency for all the processes involved. For this purpose, a telescope equipped with high-resolution silicon microstrip detectors will be used. New generation silicon crystals and an extra-precise goniometer are mandatory issues. Main goal of the experiment is to get the precise information on channeling of relativistic particles and, ultimately, on the feasibility of such technique for halo collimation at LHC. In this contribution we review the status of the setting-up of experimental apparatus and its future development in sight of the planned run in September 2006.
|
|
6. |
|
|