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ORCA (2.37 GV) is a suit of two neutron monitors and a muon telescope. It was installed at Juan Carlos I Antarctic Base on January 2019 being in operation since. Because the low level of the solar activity, only a few of solar events have been detected. The GLE 73 and three Forbush decreases. A new ORCA like detector (ICaRO, 11.5 GV) is being installed at 2200 m a.s.l in Izaña Atmospheric Observatory (Tenerife Island, Spain). On the other hand, CaLMa neutron monitor (6.95 GV) will be updated with a muon telescope made by eight 1 m2 scintillators arranged in two layers of four scintillators at some point during the next two years. These three detector will measure muons and neutrons from cosmic ray interaction with atmosphere at three different locations allowing to study the solar activity from a new perspective

Neutron monitor counting rates show, among others, a $\sim$ 1.6--2.2-year period. This period has been associated with a solar origin affecting the cosmic ray propagation conditions through the heliosphere. The duration of this period varies from one Solar Cycle to another.\cite{Comazzi_Blanco_2022} found the duration of the $\sim$ 1.6--2.2-year period ($\tau$) is linearly related to the averaged sunspot number ($SSN_a$) in each Solar Cycle.In this piece of research, we have analyzed this relationship. This equation shows that shorter $\sim$1.6--2.2-year periods occur during stronger cycles when $SSN_a$ is higher. Drawing on this relationship given by $SSN_a = (-130 \pm 10) \: \tau + (330 \pm 30)$, we computed $\tau$ for the cycles previous to the existence of neutron monitors (Solar Cycles 7--19). By means of the Huancayo neutron monitor spectrum we checked the validity of this equation along the Solar Cycle 19. Once the previous relationship is checked, $\tau$ for the current Solar Cycle 25 is computed giving $\sim$ 2.22 years.An internal mechanism of the solar dynamo called Rossby waves could produce these variations in the solar magnetic field and, indirectly, in neutron monitor counting rates.The harmonic of fast Rossby waves with $m=1$ and $n=8$ fit with the detected periodicity and the variation of the solar magnetic field strength from weaker to stronger Solar Cycles could explain the different periods detected in each cycle.Finally, a solar magnetic field strength of $\sim$ 7--25 kG in the tachocline have been estimated based on the detected periodicities using the dispersion relation for fast Rossby waves.

Neutron monitor counting rates show periodicities in the ≈ 1.6 – 2.2-year range. These periodicities have been associated with a solar origin affecting the cosmic ray propagation conditions through the heliosphere. Our hypothesis is that the periodicities in the ≈ 1.6 – 2.2-years range correspond to a single periodicity that changes its duration over time.López-Comazzi and Blanco (Astrophys. J.927(2), 155, 2022) found that the duration of the ≈ 1.6 – 2.2-year period ($\tau $ τ ) is linearly related to the average sunspot number ($SSN_{a}$ S S N a ) in each solar cycle. The relationship shows that shorter ≈ 1.6 – 2.2-year periods occur during stronger cycles when $SSN_{a}$ S S N a is higher. Therefore, the duration of this period varies from one solar cycle to another. This study focuses on this relation. For obtaining this relation, the values of the duration of the ≈ 1.6 – 2.2-year period in global neutron monitor counting rates (a virtual station determined by averaging of the different neutron monitor counting rates along the world) along the Solar Cycles 20 – 24 have been used. We extend the sample by adding the duration of the ≈ 1.6 – 2.2-year period in Huancayo neutron monitor counting rates along Solar Cycle 19 to this linear relationship. Once the linear relationship is extended, $\tau $ τ for the current Solar Cycle 25 is computed giving ≈ 2.24 years. Drawing on this more accurate relationship given by $SSN_{a} = (-120 \pm 10) \: \tau + (320 \pm 20)$ S S N a = ( − 120 ± 10 ) τ + ( 320 ± 20 ) , we computed $\tau $ τ for the cycles previous to the existence of neutron monitors (Solar Cycles 7 – 18).These ≈ 1.6 – 2.2-year periodicities in neutron monitor counting rates could be produce by variations in the solar magnetic field due to an internal mechanism of the solar dynamo called Rossby waves. Concretely, the harmonic of fast Rossby waves with $m=1$ m = 1 and $n=8$ n = 8 fit with the detected ≈ 1.6 – 2.2-year periodicity. In addition, the variation of the solar magnetic-field strength from weaker to stronger solar cycles could explain the different periods detected in each cycle. Based on the detected periodicities using the dispersion relation for fast Rossby waves, a solar tachocline magnetic-field strength of ≈ 7 – 25 kG has been estimated.

This is the fourth data paper publishing lightcurve survey work of 52 Near Earth Asteroids (NEAs) using 10 telescopes available to the EURONEAR network between 2017 and 2020. Forty six targets were not observed before our runs (88% of the sample) but some of these were targeted during the same oppositions mainly by Brian Warner. We propose new periods for 20 targets (38% of the sample), confirming published data for 20 targets, while our results for 8 targets do not match published data. We secured periods for 15 targets (29% of the sample), candidate periods for 23 objects (44%), tentative periods for 11 asteroids (21%), and have derived basic information about 3 targets (6% of the sample). We calculated the lower limit of the ellipsoid shape ratios a/b for 46 NEAs (including 13 PHAs). We confirmed or suggested 4 binary objects, recommending two of them for follow-up during future dedicated campaigns. © Crown 2022., The Isaac Newton Telescope is operated on the island of La Palma by the Isaac Newton Group of Telescopes in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias. The INT time was granted by the Spanish TAC (19 nights, proposals C85/2018A and C9/2018B), to which we added some bright time awarded by the Spanish and Dutch TACs to another project led by the same PI (proposals C29/2018A, C10/2018B and N2+C10/2020A) and other time available during the ING internal S/D service and student training. This paper is based on observations collected at the Wise Observatory with the 1 meter telescope. F. Pozo Nunez gratefully acknowledges the generous and invaluable support of the Klaus Tschira Foundation. This article is based on observations made in the Observatorios de Canarias del IAC with the Mercator telescope operated by the Institute of Astronomy, University of Leuven (Belgium) in the Observatorio del Roque de los Muchachos (10 nights, proposal C85/2018A granted by the Spanish TAC). We thank former ING student L. R. Holden for his INT observations for this project. The work of R. Gherase and M. Popescu is financed by a grant of the Romanian National Authority for Scientific Research and Innovation CNCS - UEFISCDI, project number PN-III-P1-1.1-TE-2019-1504. This research has made use of SAOImage DS9, developed by Smithsonian Astrophysical Observatory. We also made use of the VizieR service developed at CDS, Strasbourg, France, whose original description was published by Ochsenbein et al. 2000., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

[EN] Objective. The goal of this work is to extend previous peripheral nerve stimulation (PNS) studies to scenarios relevant to magnetic particle imaging (MPI) and low-field magnetic resonance imaging (MRI), where field dynamics can evolve at kilo-hertz frequencies. Approach. We have constructed an apparatus for PNS threshold determination on a subject's limb, capable of narrow and broad-band magnetic stimulation with pulse characteristic times down to 40 mu s. Main result. From a first set of measurements on 51 volunteers, we conclude that the PNS dependence on pulse frequency/rise-time is compatible with traditional stimulation models where nervous responses are characterized by a rheobase and a chronaxie. Additionally, we have extended pulse length studies to these fast timescales and confirm thresholds increase significantly as trains transition from tens to a few pulses. We also look at the influence of field spatial distribution on PNS effects, and find that thresholds are higher in an approximately linearly inhomogeneous field (relevant to MRI) than in a rather homogeneous distribution (as in MPI). Significance. PNS constrains the clinical performance of MRI and MPI systems. Extensive magneto-stimulation studies have been carried out recently in the field of MPI, where typical operation frequencies range from single to tens of kilo-hertz. However, PNS literature is scarce for MRI in this fast regime, relevant to small (low inductance) dedicated MRI setups, and where the resonant character of MPI coils prevents studies of broad-band stimulation pulses. This work advances in this direction., We thank all 51 anonymous volunteers for their participation in these studies, and Manuel Murbach for discussions. This work was supported by the European Commission under grant 737 180 (FET-Open: HistoMRI) and Ministerio de Ciencia e Innovacion of Spain for research grant PID2019-111436RB-C21. Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022)

Last January 2019, a new neutron monitor was installed at Juan Carlos I Spanish Antarctic Station (62º 39’ 46’’ S, 60º23’20’’ W, 12 m asl) located in Livingston Island (South Shetland Archipelago) close to the Antarctic Peninsula. The vertical rigidity cut-off for this new station is estimated as 3.52 GV. This new station (ORC) is composed of a BF3-based 3NM64 (ORCA) and 3 bare BF3 counters (ORCB). The neutron monitor is complemented by a muon telescope sharing a common room in a single stack. ORCA and ORCB with the Castilla-La Mancha neutron monitor (CaLMa) are the Spanish contributions to the Neutron Monitor Data Base. Because Juan Carlos I station is a summer station, one minute data is providing once a day during the Antarctic summer. One hour data are sent once a day during Antarctic winter. First measurements and future plans are provided in this work.

This paper examines the short- and mid-term periodicities (≲2 yr) in the cosmic-ray flux along 55 yr, from 1964 to 2019. The cosmic-ray flux has been computed by averaging the counting rates, in typified units, of a set of selected neutron monitors. This builds a representative virtual neutron monitor, named the global neutron monitor. The relevant discovered periodicities are ∼13.5, ∼27, ∼46–64, ∼79–83 day; Rieger-type (∼134–190 days); ∼225–309 day; and ∼1.06–1.15, ∼1.31–1.40, and ∼1.75–2.20 yr periods. The same analyses have been applied to the sunspot number (SSN) with the aim to compare the discovered periodicities and look for possible origins of these periodicities. Two main results have been achieved: the periodicities of 77–83 days, 134–190 days (Rieger type), 225–309 days, ∼1.3 yr, and ∼1.7 yr could be related to the solar dynamo, and an inversely linear relationship has been found between the average of the SSN versus the duration time for each solar cycle of the ∼1.75–2.20 yr period.

Neutron monitor counting rates and solar wind velocity, interplanetary magnetic field, sunspot number and total solar irradiance measurements from 2013 to 2018 corresponding to the end of solar maximum and the decreasing phase of the Solar Cycle 24 have been used. The main objective is to check whether the periodicities observed in the cosmic rays are affected by the magnetic rigidity or the height at which the neutron monitors are placed. A Global Neutron Monitor (GNM) has been defined as representative of the neutron monitor global network. This GNM is constructed by averaging the counting rates of a set of selected neutron monitors. The selection process is based on the combination of three new data quality criteria, which are applied to neutron monitors in the Neutron Monitor Data Base giving a final pool of 22 selected neutron monitors. Morlet wavelet analysis is applied to the GNM and the selected solar activity parameters to find the common periodicities. Short-term periodicities of 13.5, 27, 48, 92, 132 and 298 days have been observed in cosmic ray intensity. A clear inverse relationship between rigidity and spectral power has been obtained for the 13.5-, 48-, 92-, 132-day periods. A not so clear but still observed direct relationship between the height of the neutron monitors and the spectral power for the 48-, 92-, 132-day periods has been also found. The periodicity of 92 days is the one which shows the highest dependence with rigidity cutoff and height. As far as we know, this is the first time that these dependencies are reported. We think that these observations could be explained by assuming some cosmic ray intensity energy dependence in such periodicities and a competitive effect between rigidity and height.

International audience; A set of detectors devoted to investigate secondary cosmic rays has performed a latitudinal observation from Vigo (Spain) to Juan Carlos I Spanish Antarctic Station (Livingston Island, Antarctic Peninsula) aboard the Sarmiento de Gamboa oceanographic vessel from November $14^{th}$ to January $2^{nd}$. The experiment is split into two modules, one composed by a stack of 3NM64, three BF3 bare counters (NEMO) and a muon telescope (MITO) with a mini neutron monitor in a $20^{\prime}$ maritime container on the Sarmiento de Gamboa$^{\prime}$s deck and a second module (TRISTAN) consisting of a set of 3 RPC planes with a lead layer in between the second and the third plane placed in a separate temperature controlled room below the ship$^{\prime}$s deck. The complete set of instruments is the Antarctic Cosmic Ray Observatory (ORCA) that has been be installed in the Juan Carlos I Spanish Antarctic Base in Livingston Island (Antarctica). The latitudinal survey took ORCA throughout the South Atlantic magnetic anomaly along the Brazilian coast. ORCA is able to measure fluxes of neutrons of different energies, charged particles (mostly muons) and muon incident directions on the detector surface. In this work, we present the preliminary results of the latitudinal survey.

A new neutron monitor was installed at Juan Carlos I Spanish Antarctic Base (S $62^{\circ}$ $39^{'}$ $46^{''}$, W $60^{\circ}$ $23^{'}$ $20^{''}$, 12 m asl) last January 2019. The Base is located at Livingston Island (South Shetland Archipelago) close to the Antarctic Peninsula. The vertical rigidity cut-off for this new station is estimated as 3.52 GV. This new station (Antarctic Cosmic Ray Observatory) is composed by a BF3-based 3NM64 (ORCA) and 3 bare BF3 counters (ORCB). The neutron monitor is complemented by a muon telescope sharing a common room in a single stack. ORCA and ORCB with the Castilla-La Mancha neutron monitor (CaLMa) are the Spanish contribution to the Neutron Monitor Data Base. Juan Carlos I Base is a summer station, that that it operates only during the antarctic summer. This affects to communications and data transmission implying two different modes of data transmission, one minute resolution data and almost real time in summer and one hour resolution data that is sent once a day. Nevertheless, data with one minute resolution is stored in a NAS hard drive system along the year. First measurements and future plans are presented in this work.

The Muon Impact Tracer and Observer (MITO) is a new cosmic ray detector, part of the Antarctic Cosmic Ray Observatory (ORCA), recently deployed by the University of Alcala at the Juan Carlos I Spanish Antarctic Station (JCI) on Livingston Island, Antarctic Peninsula (S62o39’46”, W60o23’20”, 12 m asl). MITO is composed of two stacked 100 cm x 100 cm x 5 cm BC-400 organic scintillators, eight photomultiplier tubes (PMTs) with corresponding light guides, a 16 cm lead separation layer, and an electronic data acquisition module able to register muon flux and pulse amplitude data. The goal of this setup is to provide a real-time estimation of the muon impact points on each scintillator and, thus, the muon arrival directions, based on the comparison of the pulse heights registered by each PMT. The electronic data acquisition module has been designed using different approaches and processing technologies (analogue and digital) producing some theoretically equivalent and redundant results which can be compared and used for better reliability. In this work we present the MITO design and discuss the preliminary results of the latitudinal survey of cosmic ray fluxes performed during its cruise aboard the Sarmiento de Gamboa oceanographic research vessel from Vigo (Spain) to the Antarctic Peninsula, from November 14th, 2018 to January 2nd, 2019.

Morlet Wavelet Analysis is applied to the period 2013--2018 corresponding to the decreasing phase of the solar cycle 24. The aim is to identify characteristic periodicities between days to one years in the neutron monitor counting rates of a set of 22 neutron monitors distributed around the world and at different elevation above sea level (a.s.l). Six periodicities are observed once the one day period is removed: The synodic solar rotation (27--28.3 days) and its second harmonic, the near annual period and 47, 93 and 133 days periods. The last one is especially strong since 2014. An artificial neutron monitor power spectrum has been built by averaging the obtained power spectrum of the 22 neutron monitors. This average power spectrum is used as reference for the rest of neutron monitors. After the comparison, we have defined two indices, $Q_{j}$ and $Q_{x}$, the first one determines how much the power spectrum of a single station differs with respect to the reference spectrum and the second one is the weighted cross-correlation between a single neutron monitor and the other 21. Finally, we define a station factor quality as the mean value of $Q_{j}$ and $Q_{x}$.

Context. Teegarden's Star is the brightest and one of the nearest ultra-cool dwarfs in the solar neighbourhood. For its late spectral type (M7.0 V), the star shows relatively little activity and is a prime target for near-infrared radial velocity surveys such as CARMENES. Aims. As part of the CARMENES search for exoplanets around M dwarfs, we obtained more than 200 radial-velocity measurements of Teegarden's Star and analysed them for planetary signals. Methods. We find periodic variability in the radial velocities of Teegarden's Star. We also studied photometric measurements to rule out stellar brightness variations mimicking planetary signals. Results. We find evidence for two planet candidates, each with 1.1 M minimum mass, orbiting at periods of 4.91 and 11.4 d, respectively. No evidence for planetary transits could be found in archival and follow-up photometry. Small photometric variability is suggestive of slow rotation and old age. Conclusions. The two planets are among the lowest-mass planets discovered so far, and they are the first Earth-mass planets around an ultra-cool dwarf for which the masses have been determined using radial velocities.© ESO 2019., M.Z. acknowledges support from the Deutsche Forschungsgemeinschaft under DFG RE 1664/12-1 and Research Unit FOR2544 >Blue Planets around Red Stars>, project no. RE 1664/14-1. CARMENES is an instrument for the Centro Astronomico Hispano-Aleman de Calar Alto (CAHA, Almeria, Spain). CARMENES is funded by the German Max-Planck-Gesellschaft (MPG), the Spanish Consejo Superior de Investigaciones Cientificas (CSIC), the European Union through FEDER/ERF FICTS-2011-02 funds, and the members of the CARMENES Consortium (Max-Planck-Institut fur Astronomie, Instituto de Astrofisica de Andalucia, Landessternwarte Konigstuhl, Institut de Ciencies de l'Espai, Institut fur Astrophysik Gottingen, Universidad Complutense de Madrid, Thuringer Landessternwarte Tautenburg, Instituto de Astrofisica de Canarias, Hamburger Sternwarte, Centro de Astrobiologia and Centro Astronomico Hispano-Aleman), with additional contributions by the Spanish Ministry of Economy, the German Science Foundation through the Major Research Instrumentation Programme and DFG Research Unit FOR2544 >Blue Planets around Red Stars>, the Klaus Tschira Stiftung, the states of Baden-Wurttemberg and Niedersachsen, and by the Junta de Andalucia. Based on data from the CARMENES data archive at CAB (INTA-CSIC). This article is based on observations made with the MuSCAT2 instrument, developed by ABC, at Telescopio Carlos Sanchez operated on the island of Tenerife by the IAC in the Spanish Observatorio del Teide. Data were partly collected with the 150-cm and 90-cm telescopes at the Sierra Nevada Observatory (SNO) operated by the Instituto de Astrofisica de Andalucia (IAA-CSIC). Data were partly obtained with the MONET/South telescope of the MOnitoring NEtwork of Telescopes, funded by the Alfried Krupp von Bohlen und Halbach Foundation, Essen, and operated by the Georg-August-Universitat Gottingen, the McDonald Observatory of the University of Texas at Austin, and the South African Astronomical Observatory. We acknowledge financial support from the Spanish Agencia Estatal de Investigacion of the Ministerio de Ciencia, Innovacion y Universidades and the European FEDER/ERF funds through projects AYA2015-69350-C3-2-P, AYA2016-79425-C3-1/2/3-P, AYA2018-84089, BES-2017-080769, BES-2017-082610, ESP2015-65712-C5-5-R, ESP2016-80435-C2-1/2-R, ESP2017-87143-R, ESP2017-87676-2-2, ESP2017-87676-C5-1/2/5-R, FPU15/01476, RYC-2012-09913, the Centre of Excellence >Severo Ochoa> and >Maria de Maeztu> awards to the Instituto de Astrofisica de Canarias (SEV-2015-0548), Instituto de Astrofisica de Andalucia (SEV-2017-0709), and Centro de Astrobiologia (MDM-2017-0737), the Generalitat de Catalunya through CERCA programme>, the Deutsches Zentrum fur Luft-und Raumfahrt through grants 50OW0204 and 50OO1501, the European Research Council through grant 6 94 513, the Italian Ministero dell'instruzione, dell'universita de della ricerca and Universita degli Studi di Roma Tor Vergata through FFABR 2017 and >Mission: Sustainability 2016>, the UK Science and Technology Facilities Council through grant ST/P000592/1, the Israel Science Foundation through grant 848/16, the Chilean CONICYT-FONDECYT through grant 31 80 405, the Mexican CONACYT through grant CVU 4 48 248, the JSPS KAKENHI through grants JP18H01265 and 18H05439, and the JST PRESTO through grant JPMJPR1775.