Vacuum birefringence and dichroism signals in the PVLAS experimentUgo Gastaldi, INFN-LNL Legnaro on behalf of the PVLAS Collaboration
ICHEP’06 Moscow 27- 07- 2006
• IntroductionDYCHROISM PRL96,110406(2006) vacuum B induced rotationBIREFRINGENCE QCD-06 and ICHEP-06 vacuum B induced ellipticity
• Ellipticity measurementsPHASE and AMPLITUDE calibrations with gasesVACUUM Measurements
• OutcomeVACUUM BIREFRINGENCE has OPPOSITE SIGN of He, Ne,… Birefringencem=0.8-1.8meV M=1-7 10+5GeV 0++ boson responsible???
• ProspectsCONFIRM LIGHT BOSON INTERPRETATION by REGENERATION measurementsREDUCE NOISE INCREASE DUTY CYCLEPRECISE MEASUREMENTS OF m by changing magnet length
PVLAS Collaboration (Trieste, Pisa, Legnaro, Frascati, Ferrara): from left to right E.Polacco, E.Milotti, E.Zavattini, R.Cimino, G.Cantatore, S.Marigo, U.Gastaldi, G.Petrucci and A.Zanetti standing
G.Zavattini, M.Karuza, G.Ruoso, G.DiDomenico and F.DellaValle seated (S.Carusotto, G.Raiteri and P.Temnikov are not in the picture)
PVLAS EXPERIMENT
• SITE• MAGNET• ELLIPSOMETER• Fabry-Perot CAVITY• MODULATIONS• FINESSE • ELLIPTICITY• CONTROLS• OPERATIONS
PVLAS site:
two opposite walls of the square pit support the concrete beam (with turntable and
cryostat on top)
pit floor and pit walls rest on separate foundations
PVLAS top optical bench resting on 4 granite pillars thatsurround the (rotating) cryostat (with superconducting magnet inside)
Ne run1049_1
1.0E-6
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
1.0E-7
Frequency (Hz)507.568504.502 505.000 505.500 506.000 506.500 507.000
0.00E+0
2.00E-6
4.00E-6
6.00E-6
8.00E-6
1.00E-5
1.27E-590
180
270
N2 run1110_0 0.00E+0
2.00E-6
4.00E-6
6.00E-6
8.00E-69.33E-6
90
180
2701.0E-9
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
Frequency (Hz)507.537504.598 505.000 505.500 506.000 506.500 507.000
He run1161_00.00E+02.50E-65.00E-67.50E-61.00E-51.25E-51.50E-5
1.86E-590
180
270
1.0E-7
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
Frequency (Hz)507.474504.598 505.000 505.500 506.000 506.500 507.000
Ne run1187_0
1.0E-7
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
Frequency (Hz)507.599504.502 505.000 505.500 506.000 506.500 507.000
0.00E+0
5.00E-6
1.00E-5
1.50E-5
2.00E-5
2.67E-590
180
270
Run 807_1VacuumIR light
1.0E-6
1.0E-19
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
1.0E-7
Frequency (Hz)507.509504.514 505.000 505.500 506.000 506.500 507.000
0.00E+05.00E-81.00E-71.50E-72.00E-72.50E-73.00E-7
3.65E-790
180
270
run945_5VVacuumIR light
1.0E-5
1.0E-191.0E-18
1.0E-171.0E-161.0E-151.0E-14
1.0E-131.0E-121.0E-11
1.0E-101.0E-91.0E-81.0E-7
1.0E-6
Frequency (Hz)507.338504.647 505.000 505.500 506.000 506.500 507.000
0.00E+0
1.00E-7
2.00E-7
3.00E-7
4.00E-74.64E-7
90
180
270
Run 1101_0Vacuum
Green light
1.0E-7
1.0E-19
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
Frequency (Hz)507.504504.534 505.000 505.500 506.000 506.500 507.000
0.00E+01.00E-72.00E-73.00E-74.00E-75.00E-76.00E-7
7.98E-790
180
270
run1137_0Vacuum
Green light
1.0E-6
1.0E-19
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
1.0E-7
Frequency (Hz)507.441504.565 505.000 505.500 506.000 506.500 507.000
0.00E+02.00E-74.00E-76.00E-78.00E-71.00E-6
1.35E-690
180
270
Run 1166_0Vacuum
Green light
1.0E-6
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
1.0E-7
Frequency (Hz)507.535504.534 505.000 505.500 506.000 506.500 507.000
0.00E+02.00E-74.00E-76.00E-78.00E-71.00E-61.20E-61.40E-61.62E-6
90
180
270
1.0E-6
1.0E-19
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
1.0E-8
1.0E-7
Frequency (Hz)506.872505.197 505.400 505.600 505.800 506.000 506.200 506.400 506.600
run1167_0VacuumGreen light
0.00E+0
5.00E-7
1.00E-6
1.50E-6
2.00E-6
2.50E-6
2.99E-690
180
270
November 2005:N2+Ne + Vacuum
November 2005:N2+He + Vacuum
PVLAS: Vacuum, N2 and Ne ellipticity phases of 2004-2005 runs
PVLAS 1064nm light ISOELLIPTICITY and
ISOROTATION curves in (m,M) plane
Physics outcome
DICHROISM(IR) amplitude circa 4 10-12 (published in PRL2006) ELLIPTICITY(IR) amplitude circa 2-5 10-12, phase opposite to CME(He, Ne)
ELLIPTICITY(Gr) amplitude amplitude circa 3-15 10-12, phase opposite to CME(He, Ne)
If effects observed truly generated mostly by quantum vacuum effects and not by apparatus
If microscopic interpretation in terms of existence of ultralight bosons coupled to two photons valid
If ultralight bosons have spin zero and only one sort present
Phase opposite to CME(noble gases) tells bosons are scalars 0++m=0.8-1.8 meV M=0.1-0.7 10+5 GeV
PVLAS oasis in desert of (m,1/M)
plane
main question:oasis or mirage???
PROSPECTSConfirm LIGHT BOSON interpretation regeneration measurements (in parallel to polarization measur.s)with permanent magnet (beeing purchased to be installed below ellipsometer)
Reduce NOISEAMAGNETIC ACCESS STRUCTURE beeing installedPERMANENT MAGNETS planned in place of superconducting m.(no rotating stray field on FP mirrors and other optics elements)
Improve SIGNALIncrease DUTY CICLE with permanent magnets (no cryo. constraints)
Measure m accurately by changing length L of magnetized volume (in polarization and regeneration measurements)
PVLASafter June 2006 removal
of Fe access structure around the vertical granite support
of the top optical bench,that surrounds the cryostat
W=20 mwatt out of FP N=5 10+4 in FP, give 5 10+21 photons sec-1passing through PVLAS
magnet
C=16 10-12conversion probability
in PVLAS magnet 1m long 5.5 Tesla
8 10+10 bosons sec-1boson beams
R=16/(4x7.5) 10-12reconversion prob.
in permanent magnet0.5m long 2 Tesla
expect4 10-2 photons sec-1
regenerated in perm. mag
PVLAS superconducting Morpurgo magnet
(assembled with vertical bore)
before insertion into warm bore cryostat
Run 1092_0_2SOM 90Vacuum
B=01.0E-8
1.0E-18
1.0E-17
1.0E-16
1.0E-15
1.0E-14
1.0E-13
1.0E-12
1.0E-11
1.0E-10
1.0E-9
Frequency (Hz)507.756504.439 505.000 505.500 506.000 506.500 507.000
0.00E+0
2.00E-7
4.00E-7
6.00E-7
8.00E-7
1.00E-6
1.19E-690
180
270
Run 1091_1VacuumSOM 90B=4.35 Tesla
0.00E+0
2.00E-7
4.00E-7
6.00E-7
8.00E-7
1.00E-6
1.19E-690
180
270
0.00E+02.00E-74.00E-76.00E-78.00E-71.00E-6
1.36E-690
180
270
Run 1092_0_2VacuumSOM 90B=0 Tesla
B2 dependance of 2omegam signal
Run1091_0SOM 90
0.00E+0
2.00E-7
4.00E-7
6.00E-7
8.00E-7
1.00E-6
1.23E-690
180
270
Run1084_0SOM 0
0.00E+02.00E-74.00E-76.00E-78.00E-71.00E-6
1.36E-690
180
270
November 2005 , 1ωM peak :N2+Ne + Vacuum
November 2005 , 1ωM peak :N2+He + Vacuum
References
Iacopini and Zavattini PL85B(1979)151
Maiani, Petronzio and Zavattini PL B175(1986)359
Raffelt and Stodolsky PR D37 (1988)1237
Cameron et al. (BFST Collab.) PR D47(1993)3707
Rizzo et al. IRPC 16 (1997) 81 and refs. therein
Zavattini et al (PVLAS Collab.) PRL 96(2006)110406
Gastaldi arXiv:hep-ex/0605072 (2006) and refs. therein
October 2004:Ne + Vacuum
December 2004:Ne + Vacuum
May 2005:Ne + Vacuum
October 2004, 1ωM peak:Ne + Vacuum
December 2004 , 1ωM peak :Ne + Vacuum
May 2005 , 1ωM peak :Ne + Vacuum
B dependence:Oct. 2004, Ne 18mbar
2 ωM peak 1 ωM peak
B2
B2
B4
B dependence:Dec. 2004, Vacuum
B2
B4
PVLAS532nm and 1024nm light
ISOELLIPTICITY curves
in (m,M) plane
PVLAS 532 nmlight ISOELLIPTICITY and ISOROTATION curves
in (m,M) plane
PVLAS532nm and 1024nm light ISOROTATION curves
in (m,M) plane
---
Regeneration scheme with TWO identical OPPOSITE GOING boson beams
Regeneration scheme with TWO identical OPPOSITE GOING boson beams
Yoke of Morpurgo superconducting magnet
PVLAS Morpurgo magnet :winding of superconducting coils
PVLAS Morpurgo superconducting magnet
PVLASsuperconducting
Morpurgo magnetbefore insertion
into (liquid He) cryostat
PVLAS superconducting magnet parked in vertical assembly stand
PVLAS cryostat ( with the Morpurgo superconducting magnet inside )lowered onto the rotating table which rests onto a reinforced concrete beam
supported at its extremities by the walls of the square pit of the PVLAS site at INFN-LNL in Legnaro
Top of PVLAS cryostat parked on the floor of the pit in the PVLAS site
PVLASCRYOSTAT
PVLAScryostat
PVLAS optical bench below magnet
PVLAS optical bench
above magnet
PVLASinstallation of amagnetic
access structure (Al)to the top optical bench
and to the cryostat(July2006)
PVLAS amagnetic access structure