A new method to determine the spin tune is described and tested. In an ideal planar magnetic ring, the spin tune-defined as the number of spin precessions per turn-is given by ν s ¼ γG (γ is the Lorentz factor, G the gyromagnetic anomaly). At 970 MeV=c, the deuteron spins coherently precess at a frequency of ≈120 kHz in the Cooler Synchrotron COSY. The spin tune is deduced from the up-down asymmetry of deuteron-carbon scattering. In a time interval of 2.6 s, the spin tune was determined with a precision of the PRL 115, 094801 (2015) P H Y S I C A L

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The first detailed systematic study on the tanytarsine chironomids recorded in the Eocene amber from the Rovno region (Ukraine) revealed seven new taxa. Archistempellina gen. nov., represented by A. bifurca sp. nov. (type for the genus, male) and A. falcifera sp. nov. (male), displays characters similar to those found in Stempellina Thienemann et Bause, and is recognized as one of probable basal lineages in the subtribe Stempellinina Shilova. Corneliola gen. nov., represented by C. avia sp. nov. (male, female), combines features known from several genera of the tribe Tanytarsini, and tentatively is regarded as the closest relative of Constempellina Brundin. Rheotanytarsus alliciens sp. nov. (male), featuring a long hypopygial digitus, is considered to be the oldest species of the genus. Tanytarsus congregabilis sp. nov. (male) is the first known Eocene representative of the lugens systematic species group. A complemented description of the male of Tanytarsus serafini Giłka is provided as well.

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Here we provide evidence for the presence of non-biting midges of the subfamily Chironominae in the Mesozoic, based on descriptions of exceptionally rare amber inclusions. The subfamily has already been reported, but based on a single and unspecified record from Late Cretaceous Taimyr amber (~84 Mya). That record is here revised and confirmed. Moreover, a new find in Burmese amber locates the temporal boundary of the subfamily back to the mid-Cretaceous (probably ~100 Mya). We describe two new genera assigned to the tribe Pseudochironomini: Mesoacentron gen. nov. with the species Mesoacentron kaluginae sp. nov. (Taimyr amber) and Palaeocentron gen. nov. with the species Palaeocentron krzeminskii sp. nov. (Burmese amber), the oldest known representative of the subfamily. The systematic position of the new taxa is discussed, and a key to the identification of adult males of extinct and extant Pseudochironomini genera is presented. Insights in the phylogeny and diversification tempo of the Chironominae and Pseudochironomini in the past are also provided.