{Search for direct production of GeV-scale resonances decaying to a pair of muons in proton-proton collisions at s \sqrt{s} = 13 TeV}

A search for direct production of low-mass dimuon resonances is performed using = 13 TeV proton-proton collision data collected by the CMS experiment during the 2017–2018 operation of the CERN LHC with an integrated luminosity of 96.6 fb−1. The search exploits a dedicated high-rate trigger stream that records events with two muons with transverse momenta as low as 3 GeV but does not include the full event information. The search is performed by looking for narrow peaks in the dimuon mass spectrum in the ranges of 1.1–2.6 GeV and 4.2–7.9 GeV. No significant excess of events above the expectation from the standard model background is observed. Model-independent limits on production rates of dimuon resonances within the experimental fiducial acceptance are set. Competitive or world’s best limits are set at 90% confidence level for a minimal dark photon model and for a scenario with two Higgs doublets and an extra complex scalar singlet (2HDM+S). Values of the squared kinetic mixing coefficient ε2 in the dark photon model above 10−6 are excluded over most of the mass range of the search. In the 2HDM+S, values of the mixing angle sin(θH) above 0.08 are excluded over most of the mass range of the search with a fixed ratio of the Higgs doublets vacuum expectation tan β = 0.5

Sea ice drift tracks from the Distributed Network of autonomous buoys deployed during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition 2019 - 2021

The largest ever network of autonomous ice-tethered buoys was deployed as a Distributed Network (DN) surrounding the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Central Observatory (CO). This extensive network of 112 Global Positioning System (GPS) buoys and 12 multi-instrumented ice stations captured the annual cycle of Arctic sea ice drift and deformation for the first time as the DN traversed the Transpolar Drift Stream. GPS position data from buoys deployed during the year-long MOSAiC experiment capture sea ice drift and deformation at spatial scales ranging from 100s of meters to 200 kilometers (km) from late September 2019 into 2021. This dataset contains 216 quality-controlled drift tracks from buoys deployed at sites within a 45 km radius of the MOSAiC CO. Initial deployments began 26 September 2019 (Leg 1) with new deployments of buoys in mid-March-April 2020 (Leg 3), and August-September 2020 (leg 5). This dataset has been fully reprocessed to update drift tracks with the last of the data collected by buoys that were still operational after the initial download and processing. Complete temporal coverage of this data set is now 26 September 2019 through 23 May 2021. CC BY 4.