A proposal to use CPLEAR as antigravitometer

The reconstructed kinematics of the isotropically emitted $K^0\overline{K}^0$ and their decay vertex following a $p\overline{p}$ annihilation at rest allows to select events with specific neutral kaon topology {\it and} energy. Thus, from the accumulated events with CPLEAR one can define high statistics subgroups of any gravitationally oriented neutral kaons with $\sim \pm 60$ cm maximum vertical displacement, in order to search for (anti)gravity effects. The suggested new data analysis allows to combine for the first time upward moving $K^0$'s with downward emitted $overline{K}^0$'s, and {\it vice versa}, in order to search for any directional dependence of the $CP$ parameters. The achieved limit for the relative $K^0-overline{K}^0$ mass difference ($\sim 10^{-18}$) may be indicative of a probably unique sensitivity for the proposed antigravity search. Existing anomalous energy dependent $CP$ results along with the used non-horizontal kaon beam (having in fact an equal vertical kaon displacement per $\tau_S$ as in CPLEAR) are in favour of this proposal whatever the theoretical interpretation

Tidal streams from axion miniclusters and direct axion searches

In some axion dark matter models a dominant fraction of axions resides in dense small-scale substructures, axion miniclusters. A fraction of these substructures is disrupted and forms tidal streams where the axion density may still be an order of magnitude larger than the average. We discuss implications of these streams for the direct axion searches. We estimate the fraction of disrupted miniclusters and the parameters of the resulting streams, and find that stream-crossing events would occur at a rate of about $1/(20 {\rm yr})$ for 2-3 days, during which the signal in axion detectors would be amplified by a factor $\sim 10$. These estimates suggest that the effect of the tidal disruption of axion miniclusters may be important for direct axion searches and deserves a more thorough study.Comment: Replaced with the version accepted for publication in JCA

Overlooked astrophysical signatures of axion(-like) particles

The working principle of axion helioscopes can be behind unexpected solar X-ray emission, being associated with solar magnetic fields, which become the catalyst. Solar axion signals are transient brightenings, or, continuous radiation. We arrive at 2 exotica: a) trapped, radiatively decaying, massive axions and b) outstreaming light axions, explaining unpredictable transient solar phenomena. Then, the energy of a related phenomenon points at the birth place of the axions. The energy range below some 100 eV is a window of opportunity for direct axion searches. Indirect signatures support axions or the like as an explanation of enigmatic behaviour in the Sun and beyond. Axion antennas could take advantage of such a feed back.The working principle of axion helioscopes can be behind unexpected solar X-ray emission, being associated with solar magnetic fields, which become the catalyst. Solar axion signals can be transient brightenings as well as continuous radiation. The energy range below 1 keV is a window of opportunity for direct axion searches. (In)direct signatures support axions or the like as an explanation of striking behaviour of X-rays from the Sun