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Crystal technology at PNPI. Yuri M.Ivanov Petersburg Nuclear Physics Institute. PNPI involved in channeling studies since 1970s: 1979 - prediction of volume capture effect in bent crystals ( O.I.Sumbaev ) - PowerPoint PPT Presentation
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Crystal technology at PNPICrystal technology at PNPI
Yuri M.IvanovYuri M.Ivanov
Petersburg Nuclear Physics InstitutePetersburg Nuclear Physics Institute
PNPI involved in channeling studies since 1970s:
1979 - prediction of volume capture effect in bent crystals (O.I.Sumbaev)
1982 - observation of volume capture effect with 1GeV protons at PNPI (V.M.Samsonov, O.I.Sumbaev et al.)
1987 - invention of crystal design to focus charged particle beams (A.I.Smirnov)
1989-1992 - spin precession of particles channeled in bent crystal at FNAL
1991-1995 - focusing of proton beam at IHEP
1993-1996 - extraction of proton beam from Tevatron at FNAL
1997-2004 - multi-turn extraction and collimation of proton beam at IHEP
33Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Processing of the crystalsProcessing of the crystalsOrienting with X-rays
Cutting
Grinding and polishing
44Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Double crystal X-ray spectrometerDouble crystal X-ray spectrometer
55Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Scheme of rocking curve measurementScheme of rocking curve measurement
66Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Focusing with bent crystalFocusing with bent crystal
A.I.Smirnov 1987 Experiment PNPI-IHEPA.I.Smirnov 1987 Experiment PNPI-IHEP 1991 1991
F2 = 4r2 – R2
F - focal distance
R - bending radius of the crystal
r - radius of the exit crystal face
77Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Samples of focusing crystals Samples of focusing crystals
88Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Main results with focusing crystalsMain results with focusing crystals
Focusing of 1-5 mm parallel beam into 30-Focusing of 1-5 mm parallel beam into 30-50 micron line at distances 1-10 m50 micron line at distances 1-10 m
Deflection and transformation of divergent Deflection and transformation of divergent beamsbeams
New approach to prepare secondary New approach to prepare secondary particle beamsparticle beams
99Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Deflection and transformation of Deflection and transformation of divergent beams divergent beams
Experiment IHEP-PNPI 1995
1010Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
New approach to formation of secondary
particle beams with focusing crystals
1111Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Multi-pass extraction of proton beam Multi-pass extraction of proton beam with short bent crystalswith short bent crystals
Short bent crystal - to deflect beam into septum apertureShort bent crystal - to deflect beam into septum apertureMagnet system - to extract beamMagnet system - to extract beam
IHEP-PNPI 1998
1212Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Requirements for crystalRequirements for crystal
Hight of working area Hight of working area ~5 mm~5 mm
Width of working area Width of working area ~1 mm~1 mm
Length along beam Length along beam 0.5-5 mm0.5-5 mm
Thickness of broken layer Thickness of broken layer ~0.001 mm~0.001 mm
Precision of orientation Precision of orientation ~0. ~0.33 mrad mrad
Bending angle Bending angle 1- 1-2 mrad2 mrad
1313Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
O-crystal designO-crystal design
TypicalTypical dimensionsdimensions 5 x 5 x 50 mm35 x 5 x 50 mm3
1414Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Samples of O-crystals prepared in PNPISamples of O-crystals prepared in PNPI
Crystal
5mm
Beam Direction
Crystal Courtesy of IHEP, Protvino
Slide taken from report to EPAC02 (Paris, France) on Crystal Collimation at RHIC
1515Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Typical interference pattern from a bent face of the O-crystals
1616Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Main results with O-crystals at Main results with O-crystals at IHEPIHEP
Length along beam 3-5 mmLength along beam 3-5 mm
Extraction efficiency 60-70%Extraction efficiency 60-70%
Intensity of extracted beam ~1x10Intensity of extracted beam ~1x101212
Radiation hardness ~10Radiation hardness ~102020
Still working with efficiency ~ 40%Still working with efficiency ~ 40%
1717Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
New approach – to use Sumbaev New approach – to use Sumbaev (elastic quasimosaic) effect(elastic quasimosaic) effect
Studied by Sumbaev in 1957Studied by Sumbaev in 1957Resulted in broadening of Resulted in broadening of gamma-ray diffraction peaks gamma-ray diffraction peaks from bent quartz platesfrom bent quartz platesCaused by bending of the Caused by bending of the reflecting atomic planes (initially reflecting atomic planes (initially flat and normal to large faces of flat and normal to large faces of plate) due to crystal anisotropy plate) due to crystal anisotropy Depends on choice of Depends on choice of crystallographic plane and crystallographic plane and orientation angle of plate cutting orientation angle of plate cutting relative to a normal to the relative to a normal to the chosen crystallographic planechosen crystallographic plane
Figure from article: O.I.Sumbaev, Reflection of gamma-rays from bent quartz plates, 1957
1818Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Crystal designCrystal design
1919Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Elastic quasimosaic in Elastic quasimosaic in ddependence on ependence on cut angle for Si (111) plancut angle for Si (111) planee
T – thickness of plate
k9 – deformation coefficient
= 2k9 T , where
Plate bending radius R = 1 m
2020Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Cut Cut = 0
2121Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Rocking curves for plate with cut angle = 0
before and after bending.
EExperiment with X-raysxperiment with X-rays
2222Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Experiment with protons at IHEPExperiment with protons at IHEP
2323Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Some details of experimental setupSome details of experimental setup
2424Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
First rFirst resultesult
2525Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Quasimosaic crystals prepared for U-70Quasimosaic crystals prepared for U-70
2626Yuri M.IvanovYuri M.Ivanov CC-2005, CERN, March 7-8, 2005 CC-2005, CERN, March 7-8, 2005
Some preliminaty results with Some preliminaty results with quasimosaic crystals at IHEPquasimosaic crystals at IHEP
Length along beam 0.3-10 mmLength along beam 0.3-10 mm
Extraction efficiency 70-80%Extraction efficiency 70-80%
Intensity of extracted beam 1-4 x 10Intensity of extracted beam 1-4 x 101212