New experimental limit on photon hidden-sector paraphoton mixing

Abstract

We report on the first results of a search for optical-wavelength photons mixing with hypothetical hidden-sector paraphotons in the mass range between 10 -5 and 10 -2 electron volts for a mixing parameter greater than 10 -7 . This was a generation-regeneration experiment using the "light shining through a wall" technique in which regenerated photons are searched for downstream of an optical barrier that separates it from an upstream generation region. The new limits presented here are approximately three times more sensitive to this mixing than the best previous measurement. The present results indicate no evidence for photon-paraphoton mixing for the range of parameters investigated.PACS numbers: 11.30. Ly, 12.20, Fv 12.60.Cn, 12.90+b, 13.40.Hq The Standard Model (SM) of particle physics [1-5] provides a wonderfully successful, well-tested description of the strong, electromagnetic, and weak interactions between half-integer spin fermions and integer spin bosons at the smallest length scales and highest energies accessible in current experiments. However it has limitations: the apparent failure to explain dark energy and dark matter, an unnaturally small CPviolating parameter associated with the strong interaction, and 19 free parameters, to name a few. If the SM is part of a more fundamental theory which has some new mass scale, new dynamics and particles would appear and hence signal the new physics associated with it. Popular extensions of the SM based upon string theory for example, predict a "hidden sector" of particles that interact with the "visible sector" SM fields only with feeble, gravitational-strength couplings [6][7]. This hidden sector can be probed using very high energy accelerators such as the Large Hadron Collider at the TeV scale, and also by laser experiments at the sub-electron volt (sub-eV) energy scale [8][9][10][11][12][13][14][15][16][17][18][19][20].

Microwave background constraints on mixing of photons with hidden photons

“…(31) that would lead to the most adiabatic resonance possible for unabsorbed photons. [36,37], magnetic fields of Jupiter and earth [38], photon-regeneration-experiments [39][40][41][42][43][44], arguments of the lifetime of the Sun and the CAST search of solar axions [7,45]. The solid black line indicates the best possible bound Eq.…”

Optimizing light-shining-through-a-wall experiments for axion and other weakly interacting slim particle searches

“…This directly increases the probability of γ → ALP → γ conversion, which at small masses scales as ∝ (BL) 4 . Nearly all the current LSW experiments (ALPS [50,51], BFRT [52,53], BMV [54,55], GammeV [56], LIPSS [57,58] and OSQAR [59]) performed so far, recycle one or two of the long superconducting dipole magnets from accelerator rings, such as the ones from HERA, Tevatron or LHC. A straightforward improvement can be achieved by using a larger number of these magnets (e.g.…”

Feasibility, engineering aspects and physics reach of microwave cavity experiments searching for hidden photons and axions

“…Also shown are current experimental limits on the possible existence of a hidden photon (left panel). Strong constraints arise from the non-observation of deviations from the Coulomb law (green-yellow) [30][31][32][33], from Cosmic Microwave Background (CMB) measurements of the effective number of neutrinos and the blackbody nature of the spectrum (black) [34,35], from light-shining-through-walls (LSW) experiments (grey) [36][37][38][39][40][41][42][43][44][45], and from searches of solar hidden photons with the CAST experiment (purple) [46,47]. The current limits on axion like particles (right panel) arise from the CAST experiment [48] and LSW experiments [36-38, 40, 42-45].…”