SPOT and GPRS drifting buoys for HF Radar calibration

Traditional drifting buoys have been designed to measure the surface currents at a nominal depth of 15m with drogues of 6m height. Herein, in order to assess the performance of HF Radars two designs of Lagrangian drifting buoys have been developed and targeted to provide the vertically averaged velocity of the currents in the frst 2 and 0.5 meters of the water column. These are the layer heights of the HF Radars of RAIA observatory. The buoys were made with standard materials and of-the-shelf electronics, to keep costs as low as possible.Peer Reviewe

SPOT and GPRS drifting buoys for HF Radar calibration

9th International Workshop on Marine Technology (MARTECH), virtual, 16-18 June 2021Traditional drifting buoys have been designed to measure the surface currents at a nominal depth of 15m with drogues of 6m height. Herein, in order to assess the performance of HF Radars two designs of Lagrangian drifting buoys have been developed and targeted to provide the vertically averaged velocity of the currents in the frst 2 and 0.5 meters of the water column. These are the layer heights of the HF Radars of RAIA observatory. The buoys were made with standard materials and of-the-shelf electronics, to keep costs as low as possibleN

Model type II regression for lagrangian validation of HF radar velocities in the NW Iberian Peninsula

Two designs of lagrangian low-cost drifting buoys have been developed in order to monitor the ocean surface dynamics in the North-west Iberian Peninsula and provide ground-truth observations that can be used to assess the performance of High Frequency (HF) Radars of RAIA observatory from 2020 to 2022. Since regression model type I, which is typically used in buoy-HF radar antennas validations, does not consider the presence of errors in the observations from both instruments, regression model type II was proposed to instrument intercomparison. Furthermore, a new metric was developed to better assess both model types regressions in lagrangian validations.Peer Reviewe

Model type II regression for lagrangian validation of HF Radar velocities in the NW Iberian Peninsula

2 pages, 1 figure.-- MARTECH23, 10th Marine International Workshop on Marine Technology, 19-20 de Junio de 2023, Castellón de la PlanaTwo designs of lagrangian low-cost drifting buoys have been developed in order to monitor the ocean surface dynamics in the North-west Iberian Peninsula and provide ground-truth observations that can be used to assess the performance of High Frequency (HF) Radars of RAIA observatory from 2020 to 2022. Since regression model type I, which is typically used in buoy-HF radar antennas validations, does not consider the presence of errors in the observations from both instruments, regression model type II was proposed to instrument intercomparison. Furthermore, a new metric was developed to better assess both model types regressions in lagrangian validationsThe authors also would like to thank the support from projects RADAR ON RAIA (0461_RADAR ON RAIA_1_E, co- funded by the European Union through EP-INTERREG V-A España-Portugal POCTEP program) and STRAUSS (PID2019-106008RB-C21) funded by MCIN/AEI/10.13039/501100011033N

Angular analysis of B0→D∗−D∗+s with D∗+s→D+sγ decays

The first full angular analysis of the B0→D∗−D∗+s decay is performed using 6 fb−1 of pp collision data collected with the LHCb experiment at a centre-of-mass energy of 13 TeV. The D∗+s→D+sγ and D*− → D¯¯¯¯0π− vector meson decays are used with the subsequent D+s → K+K−π+ and D¯¯¯¯0 → K+π− decays. All helicity amplitudes and phases are measured, and the longitudinal polarisation fraction is determined to be fL = 0.578 ± 0.010 ± 0.011 with world-best precision, where the first uncertainty is statistical and the second is systematic. The pattern of helicity amplitude magnitudes is found to align with expectations from quark-helicity conservation in B decays. The ratio of branching fractions [ℬ(B0→D∗−D∗+s) × ℬ(D∗+s→D+sγ)]/ℬ(B0 → D*−D+s) is measured to be 2.045 ± 0.022 ± 0.071 with world-best precision. In addition, the first observation of the Cabibbo-suppressed Bs → D*−D+s decay is made with a significance of seven standard deviations. The branching fraction ratio ℬ(Bs → D*−D+s)/ℬ(B0 → D*−D+s) is measured to be 0.049 ± 0.006 ± 0.003 ± 0.002, where the third uncertainty is due to limited knowledge of the ratio of fragmentation fractionsS

Searches for 25 rare and forbidden decays of D+ and D+s mesons

A search is performed for rare and forbidden charm decays of the form D+(s)→h±ℓ+ℓ(′)∓, where h± is a pion or kaon and ℓ(′)± is an electron or muon. The measurements are performed using proton-proton collision data, corresponding to an integrated luminosity of 1.6 fb−1, collected by the LHCb experiment in 2016. No evidence is observed for the 25 decay modes that are investigated and 90 % confidence level limits on the branching fractions are set between 1.4 × 10−8 and 6.4 × 10−6. In most cases, these results represent an improvement on existing limits by one to two orders of magnitudeWe acknowledge support from CERN and from the national agencies: CAPES, CNPq, FAPERJ and FINEP (Brazil); MOST and NSFC (China); CNRS/IN2P3 (France); BMBF, DFG and MPG (Germany); INFN (Italy); NWO (Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MSHE (Russia); MICINN (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC (United Kingdom); DOE NP and NSF (U.S.A.). We acknowledge the computing resources that are provided by CERN, IN2P3 (France), KIT and DESY (Germany), INFN (Italy), SURF (Netherlands), PIC (Spain), GridPP (United Kingdom), RRCKI and Yandex LLC (Russia), CSCS (Switzerland), IFINHH (Romania), CBPF (Brazil), PL-GRID (Poland) and OSC (U.S.A.). Individual groups or members have received support from AvH Foundation (Germany); EPLANET, Marie Skłodowska-Curie Actions and ERC (European Union); A*MIDEX, ANR, Labex P2IO and OCEVU, and Région Auvergne-Rhône-Alpes (France); Key Research Program of Frontier Sciences of CAS, CAS PIFI, Thousand Talents Program, and Sci. & Tech. Program of Guangzhou (China); RFBR, RSF and Yandex LLC (Russia); GVA, XuntaGal and GENCAT (Spain); the Royal Society and the Leverhulme Trust (United Kingdom)S

STRAUSS GPRS drifting buoys, Atlantic Ocean - Ría de Vigo (NW Iberia) - Jul. 2022 - Sep. 2022

This item is made of 2 files: the dataset in netcdf format, a Readme.txt file including a small description of the computed variables, and 4 figures representing the buoy and the three experiments.-- Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)GPS fixes of the drifts of manufactured buoys (GPRS) under Radar On Raia Project. These buoys were used in three short experiments (< 2 day) in July - september 2022 in order to collect lagrangian observations of the superficial currents of Ría de Vigo. The data collected can also be used to validate the data collected by the HF Radar of RAIA_Vigo system. http://radaronraia.eu/Funding for this experiments were provided by Project --, funded by MCIN/AEI/10.13039/501100011033 in the R&D Projects “Research Challenges” modalityN

HF radar lagrangian validations with GPRS and SPOT buoys

Encuentro de Oceanografía Física 2022 (EOF), Las Palmas de Gran Canarias (Spain), 6-8th July 2022After adding the Leça de Palmeira (13.5 MHz) HF Radar antenna to the Galician (5 MHz) HF Radar system the project RADAR_ON_RAIA has established an international cross-border (Spain-Portugal) HF Radar network consisting in 5 sites, from Leça de Palmeira to Cabo Prior [1]. This network (Leça, Silleiro, Fisterra, Prior and Vilán) estimates the currents in the first 2 meters of the water column on shelf overlapping areas. In addition, there is another HF Radar system in the Ría de Vigo, formed by two sites (Toralla and Cíes) that works at 42.6MHz, providing high-spatial resolution observations of surface velocities in the first 0.5m of the water column. In order to correct the signals received at each station, the antennas are routinely calibrated with transponders, obtaining the Antenna Pattern Measurement (APM) used in the corrections [2]. However, to assess the quality of the data gathered by the antennas an external validation with other independent sources of velocity observations is advisable. One of the best options to undertake such a task is the use of drifting buoys [3]. To validate de data obtained by the antennas, a comparison between the surface current velocity given by the radial and total vectors with the velocity of the buoys at certain positions is done. The comparisons are based on metrics such as the root mean square error (RMSE) and the statistics derived from the linear regressions (slope, intercept, coefficient of determination and probability of rejection). In the comparisons, the standard deviations (variances) of both the data from the buoys and the HF Radar are taken into account to increase or decrease the number of data, and their quality, which enters into the comparisonsThe authors also would like to thank the support of Project RADAR ON RAIA (0461_RADAR ON RAIA_1_E) co-funded by the European Union through EP-INTERREG V-A España-Portugal (POCTEP) programN