The history of the Finnish botanical exploration of Russian Lapland in 1861 and 1863

The early Finnish expeditions to the Kola Peninsula were organised by the Societas pro Fauna et Flora Fennica. The first expedition, in 1861, was made by two separate teams. Petter Adolf Karsten and Nils Isak Fellman headed to the western part, and Gustaf Selin studied the southwestern coast and then also proceeded to the western part; Karl Emil Inberg, an entomologist, collected insects separately along the track from Kandalaksha to Kola. The second expedition, in 1863, with participation of Fellman, Mårten Magnus Wilhelm Brenner and Nils Johan Laurin, studied the coasts of the White and Barents Seas around the whole Peninsula. The historical background of these expeditions and their circumstances are described in detail and discussed. Literature sources and herbarium specimens are traced in order to produce precise maps and gazetteers of the expeditions. All these expeditions brought extensive collections of herbarium specimens of vascular plants, lichens and fungi, which laid the basis for the first systematic botanical inventory of the Kola Peninsula; algae, bryophytes and zoological specimens were also collected to some extent but not treated separately by the members of the expeditions.Peer reviewe

The Russian larch (Larix archangelica, Pinaceae) in the Kola Peninsula

A locality of the Russian larch (Larix archangelica) was discovered in 2015 in 2.8 km from the mouth of the Malaya Kumzhevaya River (Lapponia Ponojensis) during the expedition to the southeastern coast of the Kola Peninsula. This is the second occurrence of native larch in the Kola Peninsula, which is situated in ca. 100 km westwards from its continuous range in the northeastern part of European Russia. A possible origin of this locality is considered, and the locality is treated as a relic of the formerly wider distribution in the middle Holocene. The only larch tree in this lo-cality grows in a spruce-birch herb-rich forest on drained lands between a river bank and a swamp area. The tree is part of the plant community that is classified as association Aconito septentrionalis – Piceetum obovatae Zaugolnova & Morozova 2009, subassociation filipenduletosum ulmariae Zaugolnova & Morozova 2009 (Vaccinio – Piceetea Br.-Bl. in Br.-Bl., Siss. & Vlieger 1939). The conservation status of larch in Murmansk Region according to the IUCN criteria is assessed as Critically Endangere

Vascular Plant Herbarium at the Kandalaksha Strict Nature Reserve (KAND), Russia

Background The present-day demand for digital availability of distributional data in biodiversity studies requires a special effort in assembling and editing the data otherwise scattered in paper literature and herbarium collections, which can be poorly accessible or little understood to present-day users and especially automatic data processors. Our project on developing the information resource for the vascular plant flora of Murmansk Region, Russia, includes processing and making digitally available all the data on the taxonomy and distribution of this flora. So far, published distribution maps are limited to the old set in the Flora of Murmansk Region (published in 1953-1966) and the Red Data Book of Murmansk Region (ed. 2, published in 2014). These publications did not take into account the main part of the herbarium collections kept at the Kandalaksha Strict Nature Reserve, which are the basis for numerous local publications that appear scattered and, therefore, little accessible nowadays. New information We present a complete dataset of all holdings of vascular plants in the Herbarium of the Kandalaksha Strict Nature Reserve, totalling 10,218 specimens collected during 1947-2019, which are referable to 764 species and 19 subspecies. All specimens were georeferenced with the utmost precision available. This dataset offers a complete and dense coverage of the Nature Reserve's territory (islands and adjacent mainland coastal areas of the Barents and White Seas, Murmansk Region and Republic of Karelia, Russia); these data are little represented in herbarium collections elsewhere.Peer reviewe

Lichens and vascular plants in Duvefjorden area on Nordaustlandet, Svalbard

Floristic check-lists were compiled for the first time for Duvefjorden Bay on Nordaustlandet, Svalbard, based on field work in July 2012 and on data from literature and herbaria. The check-lists include 172 species of lichens and 51 species of vascular plants. Several species rare in Svalbard and in the Arctic were discovered: Candelariella borealis was new to Svalbard. 51 lichen species were newly recorded on Nordaustlandet and 131 lichen species were observed in the Duvefjorden area for the first time. Among lichen species rare in Svalbard and in the Arctic the following can be mentioned: Caloplaca magni-filii, C. nivalis, Lecidea silacea, Phaeophyscia nigricans, Polyblastia gothica, Protothelenella sphinctrinoidella, Rinodina conradii, Stenia geophana, and Tetramelas pulverulentus. Two species of vascular plants, Saxifraga svalbardensis and S. hyperborea, were found new to the Duvefjorden area. The investigated flora is represented mostly by species widespread in Svalbard and in the Arctic. Although Duvefjorden area is situated in the northernmost part of Svalbard, its flora is characterized by relatively high diversity of vascular plants and lichens. Apparently this is due to the influence of the warm North Atlantic Current

The flora and vegetation of Sosnovets Island, the White Sea

The flora and vegetation of Sosnovets Island (White Sea Throat, Murmansk Region, Russia) has been studied and described in detail. This is a small island situated within the tundra zone, largely covered by a permafrost peatland with the presence of flarks, a palsa mire, and rock outcrops. Vascular plants of Sosnovets Island include 167 species and subspecies, of which 134 species and subspecies are considered native and 33 species are alien. The number of tundra species is higher and that of boreal species is lower than on the other White Sea islands; a few species with eastern distributions in East Europe are present; 6 protected species are recorded. Alien species were mostly transported from Arkhangelsk Region but partly from Central Russia; main pathways were forage, construction and gardens; one species (Alchemilla cymatophylla) was likely introduced as a polemochore. The vegetation of Sosnovets Island is represented by a complex of lichen, dwarfshrub, cottongrass-sphagnous and sedge-sphagnous communities of the peatland, which covers the major part of the island, as well as dwarf-shrub and lichen tundras, coastal vegetation, willow thickets, dwarf cornel (Cornus suecica) and secondary anthropogenic meadows and grasslands. A palsa mire, marshes with Calamagrostis deschampsioides, highly dissected peatlands with cloudberry-crowberry-lichen communities on elevated sites and cottongrass-sphagnous communities in depressions are the unique features of the island’s vegetation.Peer reviewe

π

We report on measurements of neutral pion production in the inclusive reactions d + C → π0 + x and d + Cu → π0 + x at an incident momentum of 4.5 GeV/c per nucleon. The experiments were performed on the LHE 90-channel lead glass γ-spectrometer. The cross sections were measured over the kinematical region specified by the inequalities θπ ≤ 16° and Eπ ≥ 2 GeV (in the laboratory frame). The cumulative number and transverse momentum dependencies of the exponent n in the invariant cross section parameterization Ed3 σ / d3 p ~ Atn are investigated by comparing of the observed cross sections for π0 production on carbon and copper targets in the intervals 0.6 ≤ X ≤ 1.8 and 0.04 ≤ pT2 ≤ 0.40 (GeV/c)2. The double differential cross section for the reaction d + C → π0 + x is measured using statistics of about 4.5 · 104π0 mesons. On the basis of these data we verified the so-called cluster mechanism of π0 production. We have compared our data for the reaction d + C → π0 + x, extrapolated to θπ = 0°, with the data from another experiments on π− production: d + C → π−(0°) + x (P = 1.75 and 2.88 GeV/c per nucleon) [1]; p + d → π−(180°) + x and p + d → π+(180°) + x (P = 8.9 GeV/c per nucleon) [2]; d + p → π−(0°) + x (P = 8.9 GeV/c per nucleon) [3]. The invariant cross sections were approximated by an exponential function Ed3 σ / d3 p ~ exp(−X / X0). The slope parameter X0 at different kinetic energies of the projectiles in the range of 1.05÷8.0 GeV per nucleon is determined

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements