51 research outputs found
Russian-German collaboration in the arctic environmental research
The overview of the 20-years joint Russian-German multidisciplinary researches in the Arctic are represented in this article. Data were obtained during numerous marine and terrestrial expeditions, all-year-round measurements and observations. On the basis of modern research methods including satellite observation, radiocarbon (AMS 14C) dating of the Arctic sea sediments, isotope, biochemical and other methods, the new unique records were obtained. Special emphasis devoted to the latest data concerning modern sea-ice, ocean and sedimentation processes, evolution of the permafrost and paleoenvironments in the Laptev Sea System
Toward a warmer Arctic Ocean: Spreading of the early 21st century Atlantic Water warm anomaly along the Eurasian Basin margins
We document through the analysis of 2002–2005 observational data the recent Atlantic Water (AW) warming along the Siberian continental margin due to several AW warm impulses that penetrated into the Arctic Ocean through Fram Strait in 1999–2000. The AW temperature record from our long-term monitoring site in the northern Laptev Sea shows several events of rapid AW temperature increase totaling 0.8°C in February–August 2004. We hypothesize the along-margin spreading of this warmer anomaly has disrupted the downstream thermal equilibrium of the late 1990s to earlier 2000s. The anomaly mean velocity of 2.4–2.5 ± 0.2 cm/s was obtained on the basis of travel time required between the northern Laptev Sea and two anomaly fronts delineated over the Eurasian flank of the Lomonosov Ridge by comparing the 2005 snapshot along-margin data with the AW pre-1990 mean. The magnitude of delineated anomalies exceeds the level of pre-1990 mean along-margin cooling and rises above the level of noise attributed to shifting of the AW jet across the basin margins. The anomaly mean velocity estimation is confirmed by comparing mooring-derived AW temperature time series from 2002 to 2005 with the downstream along-margin AW temperature distribution from 2005. Our mooring current meter data corroborate these estimations
Alignment of the ALICE Inner Tracking System with cosmic-ray tracks
37 pages, 15 figures, revised version, accepted by JINSTALICE (A Large Ion Collider Experiment) is the LHC (Large Hadron Collider) experiment devoted to investigating the strongly interacting matter created in nucleus-nucleus collisions at the LHC energies. The ALICE ITS, Inner Tracking System, consists of six cylindrical layers of silicon detectors with three different technologies; in the outward direction: two layers of pixel detectors, two layers each of drift, and strip detectors. The number of parameters to be determined in the spatial alignment of the 2198 sensor modules of the ITS is about 13,000. The target alignment precision is well below 10 micron in some cases (pixels). The sources of alignment information include survey measurements, and the reconstructed tracks from cosmic rays and from proton-proton collisions. The main track-based alignment method uses the Millepede global approach. An iterative local method was developed and used as well. We present the results obtained for the ITS alignment using about 10^5 charged tracks from cosmic rays that have been collected during summer 2008, with the ALICE solenoidal magnet switched off.Peer reviewe
Transverse momentum spectra of charged particles in proton-proton collisions at GeV with ALICE at the LHC
The inclusive charged particle transverse momentum distribution is measured
in proton-proton collisions at GeV at the LHC using the ALICE
detector. The measurement is performed in the central pseudorapidity region
over the transverse momentum range GeV/.
The correlation between transverse momentum and particle multiplicity is also
studied. Results are presented for inelastic (INEL) and non-single-diffractive
(NSD) events. The average transverse momentum for is (stat.) (syst.) GeV/ and
\left_{\rm NSD}=0.489\pm0.001 (stat.) (syst.)
GeV/, respectively. The data exhibit a slightly larger than measurements in wider pseudorapidity intervals. The results are
compared to simulations with the Monte Carlo event generators PYTHIA and
PHOJET.Comment: 20 pages, 8 figures, 2 tables, published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/390
The ALICE experiment at the CERN LHC
ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries. Its overall dimensions are 161626 m3 with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008
TransArctic-2019 expedition ice thickness and snow height direct measurements at points of hydrological stations
Direct (contact) measurements of sea ice thickness, elevation and snow height performed at points of 59 hydrological (oceanographic) stations during the TransArctic-2019 expedition (28 March - 04 May 2019) are presented. Variables include time, geographical location (lat, lon) and measurements of minimum (imin, m) and maximum (imax, m) sea ice thickness, minimum (iemin, m) and maximum (iemax, m) sea ice elevation (above sea level), minimum (smi, m) and maximum (sma, m) snow height, hummock concentration (huct, in 1/10 of area coverage) and maximum hummocks height (humh, m). Data is presented in CSV, DBF and shapefile formats.
TransArctic-2019 expedition was convened by the Arctic and Antarctic Research Institute (AARI) aboard AARI research vessel "Akademik Tryoshnikov" within the area of the Arctic Basin northward of the Franz-Josef Land archipelago. Points of the stations were the helicopter landing sites chosen on sufficiently level and thick ice along the sections at a distance of 10s-100s km from the drifting ship
New records of lichens and allied fungi from the Leningrad region, Russia. X
Ten lichen species and three lichenicolous fungi are reported for the first time for St. Petersburg, the whole Leningrad Region or its western part. The lichens Bacidina indigens and Lecidella asema are new for European Russia, the lichens Bryoria kuemmerleana, Caloplaca turkuensis, Scoliciosporum pruinosum, and the lichenicolous fungus Raesaenenia huuskonenii are new for North-Western European Russia
Northern Boundary of the Range of the Clouded Apollo Butterfly Parnassius Mnemosyne (L.) (Papilionidae): Climate Influence Or Degradation of Larval Host Plants?
Volume: 36Start Page: 19End Page: 3
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