Task E - A0 and related activities

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Task E - A0 and related activities

• A.C.MELISSINOS Faculty
• S.VORONOV Res. Assoc. (2003)
• R.TIKHOPLAV Graduate Students
• S.SELETSKIY
• W.BUTLER
• --- NLC SOURCE DEVELOPMENT
• --- LASER ACCELERATION EXPERIMENT
• ELECTRON COOLING OF ANTIPROTONS IN RECYCLER
• A0 PHOTOINJECTOR (FERMILAB)
  
• SEARCH FOR COHERENT BACKGROUND FIELDS (proposed)
• PHENOMENOLOGY

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A0 (FNPL) PHOTOINJECTOR
--- Train of 800 pulses spaced 1 µs ---
Charge per pulse gt 1 nC ---
Emittance
?-mm-mr --- Pulse length
lt 1 ps Can be operated remotely from LBL,
DESY EXPERIMENTS --- Generation of
flat beams
--- Beam diagnostics for ultra-short
pulses
--- Plasma wakefield acceleration
                                           
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TEM01 (DOUGHNUT-SHAPE) MODE

• Ndglass laser with wavelength ?1054 nm is used
  compressed and amplified it will deliver 1J in
  1ps pulse
• The laser operates in the TEM01 mode
• Radial polarization (TEM01 mode) is used for
  symmetry reasons and to gain a factor of ?2 in
  accelerating field

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15 MeV
50 MeV
150 MeV
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ELECTRON COOLING
Electron Energy
3.5 MeV Electron Current
500 mA Cooling section
length 20
m Preserve electron beam focussing by using
longitudinal magnetic field 100
Gauss Tolerance on transverse field
.001 Gauss Tolerance on beam loss
lt 2
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Uncompensated field
Compensated field

The angular spread of the beam must be less than
10-4 radians
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DETECTION OF COHERENT FIELDS ?
Possibilities Coherent axion field
Dilaton field
Quintessence field
?
? ?
?
? - ?
?
In the LIGO interferometer ? 2?(3x1014)
is resonant if ? ? is also resonant,
The SIDEBANDS build up
EXAMPLE Coherent axion field h 10-20
LIGO sensitivity h 10-23
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Response of the LIGO interferometer to a
coherent high frequency wave incident at an
angle of 30
The first peak is at 37.52 kHz
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NEUTRINO SCATTERING IN A MAGNETIC
FIELD K.S.McFarland, A.C.Melissinos, N.V.Mikheev
and W.W.Repko Yaroslav University (2003)
? B ? ? ? (high energy)
Conversion probability for 50 GeV
neutrinos When B 2.2 T L 10 m
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RUNNING OF THE GRAVITATIONAL COUPLING
CONSTANT
Solid line Classical
Evolution Dotted line
Unification with the Gauge couplings
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• Supplementary slides

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Beam recirculation experiment with U-bend beam
line
Multiple improvements let us to demonstrate
stable recirculation of 0.5 A electron beam
Better understanding of beam optics and
improvements in the gun and collector design made
it possible to recirculate a beam of up to 1.7 A
at 3.5 MV for several minutes its 6 MW of beam
power!
Beam recovery after an interruption of a 1-A beam
recirculation
The use of a protection system, allowing to shut
the gun off during interruptions, helped to avoid
large drops of the Pelletron voltage and large
pressure jumps. As a result, the beam recovery
time is as low as 15 seconds
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Cooling section
Parameter Value Units
Number of solenoids 10
Length of solenoids 190 cm
Working magnetic field 100-150 G
Maximal magnetic field 200 G
Solenoid current 4 A
Coefficient of the shielding of solenoids 1000
Gap length 8 cm
Number of gap correctors 20
Number of transverse field correctors per solenoid 10
To cancel the solenoid edge effect electron at
the entrance of the cooling section should have a
proper angular momentum. To impart an angular
momentum onto the electron beam the electron gun
is immersed in a solenoidal magnetic field. Thus,
a beam is produced by a 5-mm diameter cathode in
a 600-G magnetic field and then propagated to the
cooling section, where it is injected into a
150-G solenoid.
Algorithm of field correction was used to set the
field of required properties
Simulation of electrons motion in the
compensated magnetic field
Simulation of electrons motion in uncompensated
magnetic field
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