PoS(KMI2017)008 http://pos.sissa.it/ ∗ [email protected] Speaker. is a chargeless massivesuitable particle for precision with measurement the of lifetimeexperimental the in studies small the to influence macroscopic search of range, new unknownpulsed physics. interactions which provided by with is We J-PARC have and slow the started neutrons.types advanced the optical of devices high Combination enables precision us of measurements. to The perform the explain unknown new the source matter of universe. large One of CP the violation strongestis should constraint the exist of result the to of search neutron for electric the large dipole CP-violation neutron moment. EDM We by are using now dynamical discussing another of approach neutronThe to wave search enhancement with non-centrosymmetric of . the violation ofreaction time-reversal for symmetry some is nuclei. predicted in Weneutron have the resonance also started capture reaction the at feasibility J-PARC.range Non-Newtonian to is effect search of lead the the by T-violation gravity with thegas at the existence target the enables of short us extra-dimension to ofhand, measure the we the space. are interaction now at planning Neutron the theby scattering range unknown using of with force the the search noble interferometer. order lead of by 1 dark energy, nm. like chameleon On field, the other ∗ Copyright owned by the author(s) under the terms of the Creative Commons c Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). The 3rd International Symposium on "Quest5-7 for January the 2017 Origin of Particles andNagoya University, the Japan Universe" Masaaki Kitaguchi Center for Experimental Studies, KMI, NagoyaE-mail: University Search for unknown interaction with neutrons PoS(KMI2017)008 (2.1) can be writ- ) and the spin ) In, and so on, J J is the angular- ( 115 ) Masaaki Kitaguchi κ J ( κ Xe, 131 -rays from the compound γ La, 139 times larger in a several nuclei. 6 , P σ ∆ T W W ) J 1 ( κ = ]. The advantage to apply the enhancement mechanism 2 CP σ ]. The asymmetry of the capture cross section with respect ∆ 1 denote the CP- and P-violating matrix elements. This means that must be measured. The angular-momentum factor ) W J ( -ray transition are known. κ are the CP-violating and P-violating cross section, and γ germanium spectrometer. Target nuclei were T P σ W π -rays has been also measured. Detailed analysis is now in progress. ∆ γ and ]. This measurement requires that both the spin of the compound state ( 3 CP σ ∆ Combination of the intense pulsed neutrons and the germanium detectors with high energy res- Neutron is a chargeless massive particle with the lifetime in the macroscopic range, which The large charge-parity (CP) symmetry violation is required to explain theThe today’s large enhancement matter of parity (P) violation of the weak interaction contained in the nuclear ten with the partial neutronneutron widths width of can p-wave be resonance. measured by Whenresonance the we [ angular assume distribution s-p of mixing, individual the partial the candidate nuclei for T-violationhowever, search the parameter are the nuclei with large enhancement of P-violation, The enhancement is explained asboring s-wave the and result p-wave amplitudes. of The thetheoretically mechanism to of entrance be the applicable channel P-violating to effect interference enhance has the betweenviolation been experimental effect neigh- proposed sensitivity in to the search p-wave the resonances time-reversal [ (T) where momentum factor, of the final state of the olution enables us to perform thisat kind the of beamline measurements. BL04 We ANNRI areis in now measured performing J-PARC. with The the 4 experiments angular distribution of resonance capture reaction is that takes T-odd effectsthe due neutron to propagation the through final-state theenhancement interaction target of T-violation is material is can expected given as be to described be by negligibly the small neutron as optics. The to the helicity of incident neutrons was enhanced by at most 10 which were the nuclei withcompound large nuclei enhancements has of been P-violation. measuredof with the The very individual resonance high parameters energy of resolution. the The angular distributions is suitable for precision measurementexperimental of studies to the search small unknown interactions influence with slow ofneutrons neutrons. provided new Combination by physics. of J-PARC the and pulsed We the have advancedhigh optical started precision devices the enables measurements. us to In perform thistwo new are paper, types about four of CP-violation topics search, of and our the research others are project about are exotic reported. interaction. 2. The CP violation 2.1 Search for T-violating effect in resonance capture reaction universe. In order to discuss newlarge physics CP-violation beyond is the quite standard important. model of particle, the search for the interaction was discovered in 2000’s [ Search for unknown interaction with neutrons 1. Introduction PoS(KMI2017)008 (2.2) cm (90% · e 26 − . t 10 Masaaki Kitaguchi × 3 epi-thermal detector neutron < | n d is the interaction time. The | at sample position sample at t )$"

× "'"( ˆ & I ( ·

!"#"$% Xe , ) nat N ˆ k 1 √ × 4cm x 4cm x 20cm Solid Polarization 0.25 ˆ Et I 2 ( · ∝

n σ ′ d ∆ ˆ k σ ′ is the applied electric field, and × ]. Although next-generation UCN sources are being devel- 4 E 100 atm cm He spin filter 3 Polarization 0.7 ). Helium and/or proton spin filter are discussed as a neutron po- Transmission 0.4 Transmission 1 Experimental design for T-violation search at J-PARC. $'(+ )* &'( Schematic view of T-violating correlation in the neutron-nuclei reaction. Figure 2: ], it is valuable and very important to develop different methods to measure the 8 , !"!#$% 7 . We have started the development of the detector with liquid scintillator. We empha- , 6 6 − Figure 1: , is the number of neutrons, 5 J-PARC Moderator J-PARC ). N 2 The sensitivity of nEDM search written as Non-zero value of the permanent electric dipole moment of neutrons (nEDM) signals the vi- To measure the T-odd correlation term, both of neutron polarization and target polarization where high sensitivity of the UCN method is achieved with the extremely large value of nEDM for confirming the present upperimprove limit the with experimental different sensitivity. systematic uncertainties and hopefully oped intensively at accelerator-based neutron facilities formethod improving [ the upper limit with the UCN olation of time-reversal (T) invariance.world, Although the experimental nEDM searches has have not yet been been pursued observed. in The the present upper limit is 2.2 EDM search with diffraction size that the series of existingexample, technique we can be are applied discussing for the the(Fig. T-violation feasibility search of experiments. the For experiment with polarized Xe target in J-PARC techniques are required (Fig. Search for unknown interaction with neutrons larizer. We are also discussing thepumping (SEOP) polarization and/or of dynamical the nuclear polarization target (DNP). nucleispeed Research by and neutron development using detector of are spin High required exchange to optical order measure of the 10 small asymmetry of capture cross section of the C.L.), which is very close tophysics, the for predictions example, of supersymmetry. new The physicswas beyond most obtained the stringent in standard upper the model limit spin of of precessionultra-cold particle frequency the neutrons in nEDM (UCN both measurement method) magnetic field [ and electric field of confined PoS(KMI2017)008 , 11 V/cm. The 8 10 × Masaaki Kitaguchi ). This wave feels 2 3 = E V/cm 8 electric field ~ 10 3 neutron standing wave neutron neutron standing wave neutron

non-centrosymmetric crystal non-centrosymmetric neutron beam neutron ) crystal. 20 ]. We have started to study the feasibility of EDM measurement with Bismuth GeO 12 10 , instead of quartz. The electric field in the bismuth germanate crystal is estimated ··· ]. The effective electric field was experimentally measured to be Neutron wave propagation according to dynamical diffraction in non-centrosymmetric crystal. 9 V/cm [ ]. A new possible force which couples to mass can be seen at short-range. Generally, the 9 Some models beyond the standard model predict the existence of non-Newtonian gravity [ Neutrons with the proper incident angle are reflected and transmitted in the crystal according to On the other hand, some types of non-centrosymmetric crystals have strong effective electric 13 , Figure 3: 12 3. Intermediate-range force 3.1 Short-range force search with gas scattering the strong effective electric field inThe the effective crystal, electric which makes field precession can ofrotation be electric in measured dipole the by moment. Schwinger using magnetic thisin field, dynamical the which diffraction electric effects. is field, induced The is bypolarized spin neutron measured. passing beamline neutron BL17 We magnetic Sharaku are moment in now J-PARC. trying to measure the electric field of BGO at the Germanate (Bi Bragg’s law. On the entry to theIn crystal, the both case waves are of refracted the duecan periodic to be boundary the written Fermi condition as pseudopotential. a of superposition the ofwaves single two makes crystal, Bloch the functions. propagation the of The propagation standing result of of wave each along the interference to wave between the the crystal lattice (Fig. field inside their lattice.the Although crystal the is interaction shorter timethe than of strong that the electric of field cold UCNs, and neutronsto the more which improve achieved intense pass the sensitivity incident through sensitivity flux. can iffield be Furthermore, and we competitive this has successfully because method a prepare of has largereported a a [ dimension. crystal potential which The has nEDM experiments much with stronger quartz electric crystals have been already Search for unknown interaction with neutrons electric field can be increasedlead by oxide, about an order ofas magnitude 10 by employing bismuth germanate, PoS(KMI2017)008 (3.1)

Masaaki Kitaguchi 600 mm is a Compton wave He two dimensional 3 λ 3 He 2D PSD ]. This means that the 22 ]. In the range below 10 nm, , 16 ,  r λ 15 , − ]. Scattering of slow neutron with atom  14 18 LiF Beam stopper , exp 17 α 2 4 m Vacuum chamber Vacuum are masses of two particles, 1 1790 mm r 2 m N m , G 1 m − Gas cell 145 mm ) = r ( V 530 mm . For the target, we used the noble gases because they don’t have 4 neutrons is a coupling constant. The constraints above 10 nm were measured α ]. One of the candidates of the dark energy is the chameleon mecha- The setup of gas scattering experiment at BL05 NOP in J-PARC. 21 , is written as Yukawa-type potential like Collimator 20 V , 19 Figure 4: is the gravitational constant, N G The accelerating expansion of the universe suggests that the unknown energy called as dark We are planning to improve our statistics by increasing the Xe gas pressure in the gas cell and Neutron interferometer has the advantage to measure the gravitational potential precisely (Fig. The apparatus was installed into beamline BL05 NOP. The schematic view of the experimen- ). The change of the potential results the phase shift of the interferogram. The experimental 5 where nism, which modify the gravity in the presence of the matter density [ 3.2 Dark energy search with neutron interferometer energy exists [ by using torsion balances or isoelectronic techniques [ using a larger beam size to update the sensitivity. length of new boson and molecular or crystal structure, atomic spin.dependence In of order the to target, estimate we the used effectplates helium, of were argon, gas and utilized pressure xenon for gas and the for mass windowsposition the of targets. sensitive the The gas detector thin cells was aluminum to used reducewas to the performed scattering. in measure June the 2016. scatteringscattering We distribution. are distribution also including The developing finite first the volumeeffects physics Monte-Carlo precisely. of simulation run The to the analysis calculate gas by the comparing cell, the gas data thermal with the motion, simulations and are on the going. other gravitational potential should change near the matter. tal setup is shown in figure Search for unknown interaction with neutrons unknown potential with atoms has theinteraction advantage and to Van der make Waals a force constraint arecan because suppressed be the explained [ by electromagnetic using Bornforward approximation. scattering The existence distribution, of although the Yukawa-typemeasurement the force causes of nuclear the the interaction angular makes distributionrange of isotropic force. the scattering. We scattering are enables The now us performing to the search neutron the scattering experiment unknown at short- J-PARC. PoS(KMI2017)008 Masaaki Kitaguchi 5 bulk matter Neutron interferometer Neutron

Chameleon field Neutron Schematic view of chameleon search with neutron interferometer. Figure 5: Neutron is suitable for precision measurement to search new physics. Combination of the [1] G. E. Mitchell, Physics Reports 354,[2] 157?241 (2001). V. P. Gudkov, Phys. Rep. 212, 77[3] (1992). Flambaum,V.V. O.P. Sushkov, Nucl. Phys. A 412,[4] 13 (1984). C.A. Baker, et al., Phys. Rev.[5] Lett. 97 131801A. (2006). Saunders, et al., Phys. Lett.[6] B 593A. 55 Anghel, (2004). et al., Nucl. Instr.[7] and Meth.Y. A Masuda, 611 et 272 al., (2009). Phys. Rev. Lett.[8] 89 284801N. (2002). Fomin, et. al., Nucl. Instr.[9] and Meth. Fedorov,V.V. A et. 773, al., 45-51 Physica (2015). B: Condensed Matter 297, 293 (2001). intense pulsed neutrons and the advancedprecision optical measurements. devices The enables large us enhancement toone perform of of new T-violating the effect types powerful in of techniques compound high way nuclei to to can search measure be CP-violation. the nEDM Theneutron with crystal different interferometer diffraction systematic have method uncertainties. is the Gasdevelopment another advantage scattering for experiment to each and experiment study have gravity-like started in unknown J-PARC. forces. ResearchReferences and [10] V.L. Alexeev, et al., Nucl. Instr. and[11] Meth. A,Nima 284, Arkani-Hamed, 181 Savas (1989). Dimopoulos, and Gia[12] Dvali, Phys.Nima Lett. Arkani-Hamed, B Savas 429, Dimopoulos, 263?272 and (1998). Gia[13] Dvali., Phys.Y. Rev. fujii, D Nature 59, Physical 086004 Science, (1999). 234, 5?7 (1971). 4. Conclusion Search for unknown interaction with neutrons searches was performed bychameleon using dark energy. small neutron Theeter. sensitivity interferometer, Large depends scale there on of was silicon the perfectsmall no interaction crystal piece length evidence ingots of inside are for interferometer prepared the for the forOptics interferom- test this and the experiment. Interferometry ingots. We Facility fabricated (NIOF) The a in test NIST. experiments are now started at Neutron PoS(KMI2017)008 Masaaki Kitaguchi 6 Search for unknown interaction with neutrons [14] E. Fischbach, et. al., Phys. Rev.[15] D 64, 075010M. (2001). Bordag, et. al., Phys. Rep.[16] 353, 1?205R. (2001). S. Decca, et. al., Phys.[17] Rev. Lett. 94,V. V. 240401 Nesvizhevsky, et. (2005). al., Phys. Rev. D[18] 77, 034020Y. Kamiya, (2008). et. al., Phys. Rev. Lett.[19] 114, 161101J.A. (2015). Frieman, M.S. Turner, and D.[20] Huterer, Annu. Rev.B. Astron. Ratra Astrophys. and 46, P. 385 J. (2008). E.[21] Peebles, Phys. Rev.R. D R. 37, Caldwell, 3406 R. (1988). Dave, and[22] P. J. Steinhardt,J. Phys. Khoury Rev. and Lett. A. 80, Weltman, 1582 Phys. (1998). [23] Rev. Lett. 93,H. 171104 Lemmel (2004). et al. Phys. Lett. B 743, 310 (2015).