pdgLive Home   >   ${{\mathit N}}$ BARYONS ($\mathit S$ = 0, $\mathit I$ = 1/2)   >   ${{\mathit n}}$   >   LIMIT ON ${{\mathit n}}{{\mathit n}^{\,'}}$ OSCILLATIONS

LIMIT ON ${{\mathit n}}{{\mathit n}^{\,'}}$ OSCILLATIONS

INSPIRE   PDGID:

S017NOS

Lee and Yang (LEE 1956 ) proposed the existence of mirror world in an attempt to restore global parity symmetry. A possible candidate for dark matter. Limits depend on assumptions about fields ${{\mathit B}}$ and ${{\mathit B}^{\,'}}$. See the papers for details. See BEREZHIANI 2018 for a recent discussion.

VALUE (s) CL% DOCUMENT ID TECN  COMMENT $> 352$ 95 1 ABEL 2021 CNTR UCN, scan of ${{\mathit B}}$ field $\bf{> 448}$ 90 SEREBROV 2009 A CNTR Assumes ${{\mathit B}^{\,'}}$ $<$ 100 nT • • We do not use the following data for averages, fits, limits, etc. • • 2 ALMAZAN 2022 CNTR STEREO, hidden neutron search $\vert{}{\mathit m}_{{{\mathit n}}}–{\mathit m}_{{{\mathit n}^{\,'}}}\vert{}{}\geq{}$ 0. $>17$ 95 3 BEREZHIANI 2018 CNTR UCN, scan of ${{\mathit B}}$ field $> 12$ 95 4 ALTAREV 2009 A CNTR UCN, scan 0${}\leq{}{{\mathit B}}{}\leq{}$12.5 $\mu $T $> 414$ 90 SEREBROV 2008 CNTR UCN, ${{\mathit B}}$ field on $\&$ off $> 103$ 95 BAN 2007 CNTR UCN, ${{\mathit B}}$ field on $\&$ off 1  ABEL 2021 determine several limits on the oscillation time as a function of the ratio mirror magnetic field ${{\mathit B}^{\,'}}$ to applied magnetic field ${{\mathit B}}$. The quoted limit of 352 s is for ${{\mathit B}^{\,'}}$ = 0. Lower limits on the oscillation time of 6 seconds are further obtained for any mirror field ${{\mathit B}^{\,'}}$ in the range $0.4 - 25.7$ $\mu $T. 2  ALMAZAN 2022 reports an experimental constraint on the probability for neutron conversion into a hidden neutron, $\mathit p$ $<$ $3.1 \times 10^{-11}$ at 95$\%$ CL, which may be used to set a limit on the ${{\mathit n}}{{\mathit n}^{\,'}}$ oscillation time. 3  The ${{\mathit B}}$ field was set to (0.09, 0.12, 0.21) G. Limits on oscillation time are valid for any mirror field ${{\mathit B}^{\,'}}$ in ($0.08 - 0.17$) G, and for aligned fields ${{\mathit B}}$ and ${{\mathit B}^{\,'}}$. For larger values of ${{\mathit B}^{\,'}}$, the limits are significantly reduced. 4  Losses of neutrons due to oscillations to mirror neutrons would be maximal when the magnetic fields ${{\mathit B}}$ and ${{\mathit B}^{\,'}}$ in the two worlds were equal. Hence the scan over ${{\mathit B}}$ by ALTAREV 2009A: the limit applies for any ${{\mathit B}^{\,'}}$ over the given range. At ${{\mathit B}^{\,'}}$ = 0, the limit is 141 s (95$\%$ CL).

References:

ALMAZAN 2022 PRL 128 061801 Searching for Hidden Neutrons with a Reactor Neutrino Experiment: Constraints from the STEREO Experiment ABEL 2021 PL B812 135993 A search for neutron to mirror-neutron oscillations using the nEDM apparatus at PSI BEREZHIANI 2018 EPJ C78 717 New experimental limits on neutron - mirror neutron oscillations in the presence of mirror magnetic field ALTAREV 2009A PR D80 032003 Neutron to Mirror-Neutron Oscillations in the Presence of Mirror Magnetic Fields SEREBROV 2009A NIM A611 137 Search for neutronmirror neutron oscillations in a laboratory experiment with ultracold neutrons SEREBROV 2008 PL B663 181 Experimental Search for Neutron$−$Mirror Neutron Oscillations using Storage of Ultracold Neutrons BAN 2007 PRL 99 161603 Direct Experimental Limit on Neutron$−$Mirror-Neutron Oscillations