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Abstract Acoustic waves generated by seismic waves contain information on the internal structure of planets, and can be sensed by pressure sensors onboard high-altitude balloons. To identify the various contributions (infrasound signal, noise, balloon response, etc.) in such pressure records, a full waveform modeling is implemented and completed by infrasound ray tracing and additional data analysis. Here, we analyze the Stratéole-2 pressure data associated with two earthquakes (Garcia et al. Geophys. Res. Lett. 49(15):e98844, 2022) and compared these to full waveform simulations by SPECFEM2D-DG-LNS software. Even if our simulations do not precisely reproduce the waveform observed in the frequency range [0.05, 0.3] Hz, we show that the waveform presents more sensitivity to quake and internal structure parameters than to atmospheric structure, and that seismic surface wave dispersion is observed in balloon pressure records. The long-duration pressure oscillations observed after the main infrasonic signal cannot be fully reproduced by our one-dimensional input model even when source time function complexity and aftershocks are considered. These features are ascribed mainly to the complex vertical ground movements below the balloon and partly to late secondary infrasound arrivals excited by the interactions of seismic waves with the topography. These results enhance the advantages and limitations of quake-related infrasound observations on board terrestrial and planetary balloon platforms. Graphical Abstract

We propose an experimental scheme for performing sensitive, high-precision laser spectroscopy studies on fast exotic isotopes. By inducing a stepwise resonant ionization of the atoms traveling inside an electric field and subsequently detecting the ion and the corresponding electron, time-, and position-sensitive measurements of the resulting particles can be performed. Using a mixture density network, we can leverage this information to predict the initial energy of individual atoms and thus apply a Doppler correction of the observed transition frequencies on an event-by-event basis. We conduct numerical simulations of the proposed experimental scheme and show that kHz-level uncertainties can be achieved for ion beams produced at extreme temperatures (>10^{8} K), with energy spreads as large as 10 keV and nonuniform velocity distributions. The ability to perform in-flight spectroscopy, directly on highly energetic beams, offers unique opportunities to study short-lived isotopes with lifetimes in the millisecond range and below, produced in low quantities, in hot and highly contaminated environments, without the need for cooling techniques. Such species are of marked interest for nuclear structure, astrophysics, and new physics searches.

Abstract We have modeled the high‐frequency seismogram envelopes of the large event S1222a and four recently identified near impacts recorded by the InSight mission by introducing a stratification of velocity and attenuation into a multiple‐scattering approach. We show that a simple conceptual model composed of a strongly diffusive, weakly attenuating layer overlying a transparent medium captures the essential features of the observed envelopes. The attenuation profiles reveal that the minimal extension of heterogeneities at depth is of the order of 20 km in the vicinity of InSight and 60 km on the path to S1222a. We interpret this result as an indication that the Martian crust as a whole is at the origin of the strong scattering. Our heterogeneity model suggests that the sources of a number of distant Very‐high‐Frequency seismic events are shallow and located to the south or in close vicinity of the Martian dichotomy.

Laser spectroscopic measurements of isotopes near the doubly-magic 100-Sn are challenging due to difficulties in their production. Here the authors measure the ground state charge radius of the proton-rich 96-Ag isotope and find a discontinuity in the nuclear size when crossing the neutron number N equal to 50.

Abstract The tidal response of Mars, due to the Sun and the Martian moons, Phobos and Deimos, provides information about the interior structure of Mars. By using the Very Broad Band (VBB) seismometer of Seismic Experiment for Interior Structure (SEIS) as a gravimeter on the surface of Mars, the InSight mission will provide the long‐period data suited to tidal analysis: most notably, the proximity of Phobos implies that degree 2, 3, 4, and further tides will be detectable by the VBB and are expected to provide information about the rheology at different depths within Mars. In order to expedite the recovery of these tidal signals in the SEIS measurements, we model the tides raised by Phobos using a tidal potential deduced from JPL Horizons ephemerides. From this potential, we calculate the expected tidal acceleration at InSight's location and gravimetric factors using a set of plausible interior models of Mars. To simulate the expected long period signal on the VBB seismometer, we use the InSight Auxiliary Payload Sensor Suite data to model the noise seen at low frequency by SEIS mainly due to temperature and pressure variations. Based on this synthetic signal, by applying filtering methods such as stacking and matched filtering to these synthetic data, we show that by recovering the gravimetric factors, it should be possible to constrain the state of the core and its size with an accuracy of 125 km after two Earth years.

Abstract: The aim of this work was to evaluate the operational performance of a tractor and precision planter-fertilizer set during corn sowing, under three displacement speeds: 3.0, 5.0 and 8.0 km h-1 (0.83, 1.40 and 22.2 m s-1) and two kinds of sowing – direct and conventional. The design used was on randomized blocks, in a 3x2 factorial arrangement, with three repetitions for each treatment. Data was gathered on tractor average traction power; average power on tractor drawbar; performance on drawbar; effective field capacity; field efficiency; hourly fuel consumption; specific fuel consumption; operational fuel consumption; energetic fuel consumption per area; slip of wheelsets and longitudinal distribution of seeds. It was observed that displacement speed influenced the variables: power on tractor drawbar; performance on drawbar; hourly fuel consumption; specific fuel consumption; operational fuel consumption; effective field capacity; field efficiency; slip of wheelsets and longitudinal distribution of seeds.

We demonstrate that the pulsed-time structure and high-peak ion intensity provided by the laser-ablation process can be directly combined with the high resolution, high efficiency, and low background offered by collinear resonance ionization spectroscopy. This simple, versatile, and powerful method offers new and unique opportunities for high-precision studies of atomic and molecular structures, impacting fundamental and applied physics research. We show that even for ion beams possessing a relatively large energy spread, high-resolution hyperfine-structure measurements can be achieved by correcting the observed line shapes with the time-of-flight information of the resonantly ionized ions. This approach offers exceptional advantages for performing precision measurements on beams with large energy spreads and allows measurements of atomic parameters of previously inaccessible electronic states. The potential of this experimental method in multidisciplinary research is illustrated by performing, for the first time, hyperfine-structure measurements of selected states in the naturally occurring isotopes of indium, ^{113,115}In. Ab initio atomic-physics calculations have been performed to highlight the importance of our findings in the development of state-of-the-art atomic many-body methods, nuclear structure, and fundamental-physics studies.

This paper reports on the hyperfine-structure and radioactive-decay studies of the neutron-deficient francium isotopes ^{202–206}Fr performed with the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at the ISOLDE facility, CERN. The high resolution innate to collinear laser spectroscopy is combined with the high efficiency of ion detection to provide a highly sensitive technique to probe the hyperfine structure of exotic isotopes. The technique of decay-assisted laser spectroscopy is presented, whereby the isomeric ion beam is deflected to a decay-spectroscopy station for alpha-decay tagging of the hyperfine components. Here, we present the first hyperfine-structure measurements of the neutron-deficient francium isotopes ^{202–206}Fr, in addition to the identification of the low-lying states of ^{202,204}Fr performed at the CRIS experiment.

In this paper, we report a new design of a multifunction RFID tag antenna operating in the European band (665-868.5MHz) and the North American band (902-928 MHz) separately. The multifunction behavior can be achieved by changing the position of the RFID chip. It is found that at each feeding position, the RFID tag antenna can operate separately on both bands. The characteristics of the proposed design including S-parameters, impedance and reading range pattern have been investigated using simulation software CST Microwave Studio and experimental results. Further insight into the mechanism radiation is sought through the investigation of the current density and the equivalent circuit model. The tolerance of this design on various background materials is also investigated experimentally. The measured and simulated results show good agreement, providing a simple and low-cost design.

Summary.  Our purpose was to determine the blood amino acid concentration during insulin induced hypoglycemia (IIH) and examine if the administration of alanine or glutamine could help glycemia recovery in fasted rats. IIH was obtained by an intraperitoneal injection of regular insulin (1.0 U/kg). The blood levels of the majority of amino acids, including alanine and glutamine were decreased (P [ABSTRACT FROM AUTHOR]

With increasing demand for accurate calculation of isotope shifts of atomic systems for fundamental and nuclear structure research, an analytic energy derivative approach is presented in the relativistic coupled-cluster (CC) theory framework to determine the atomic field shift and mass shift (MS) factors. This approach allows the determination of expectation values of atomic operators, overcoming fundamental problems that are present in existing atomic physics methods, i.e. it satisfies the Hellmann–Feynman theorem, does not involve any non-terminating series, and is free from choice of any perturbative parameter. As a proof of concept, the developed analytic response relativistic CC theory has been applied to determine MS and field shift factors for different atomic states of indium. High-precision isotope-shift measurements of In were performed in the 246.8 nm (5p 2P3/2 9s 2S1/2) and 246.0 nm (5p 2P1/2 8s 2S1/2) transitions to test our theoretical results. An excellent agreement between the theoretical and measured values is found, which is known to be challenging in multi-electron atoms. The calculated atomic factors allowed an accurate determination of the nuclear charge radii of the ground and isomeric states of the In isotopes, providing an isotone-independent comparison of the absolute charge radii. [ABSTRACT FROM AUTHOR]

An experimental setup for sensitive high-resolution measurements of hyperfine structure spectra of exotic calcium isotopes has been developed and commissioned at the COLLAPS beam line at ISOLDE, CERN. The technique is based on the radioactive detection of decaying isotopes after optical pumping and state selective neutralization (ROC) (Vermeeren et al 1992 Phys. Rev. Lett.68 1679). The improvements and developments necessary to extend the applicability of the experimental technique to calcium isotopes produced at rates as low as few ions s–1 are discussed. Numerical calculations of laser-ion interaction and ion-beam simulations were explored to obtain the optimum performance of the experimental setup. Among the implemented features are a multi-step optical pumping region for sensitive measurements of isotopes with hyperfine splitting, a high-voltage platform for adequate control of low-energy ion beams and simultaneous β-detection of neutralized and remaining ions. The commissioning of the experimental setup, and the first online results on neutron-rich calcium isotopes are presented. [ABSTRACT FROM AUTHOR]

The odd-odd 54,56,58,60,62,64Mn isotopes (z = 25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperhne spectra the spins and magnetic moments of Mn isotopes up to N = 39 were extracted. The previous tentative ground state spin assignments of 58,60,62,64Mn are now firmly determined to be I = 1 along with an I = 4 assignment for the isomeric states in 58,60,62Mn. The I = 1 magnetic moments show a decreasing trend with increasing neutron number while the I = 4 moments remain quite constant between N = 33 and N = 37. The results are compared to large-scale shell-model calculations using the GXPF1A and LNPS effective interactions. The excellent agreement of the ground state moments with the predictions from the LNPS calculations illustrates the need for an increasing amount of proton excitations across Z = 28 and neutron excitations across N = 40 in the ground state wave functions from N = 31 onwards. [ABSTRACT FROM AUTHOR]

The magnetic dipole moments and changes in mean-square charge radii of the neutron-rich 2l8m,2l9,229,23lFr isotopes were measured with the newly installed Collinear Resonance Ionization Spectroscopy (CRIS) beam line at the On-Line Isotope Mass Separator (ISOLDE), CERN, probing the 7s²S1/2 to 8p2 P3/2 atomic transition. The δ(r²)A-221 values for 218m,219Fr and 229,23lFr follow the observed increasing slope of the charge radii beyond N = 126. The charge radii odd-even staggering in this neutron-rich region is discussed, showing that 220Fr has a weakly inverted odd-even staggering while 228Fr has normal staggering. This suggests that both isotopes reside at the borders of a region of inverted staggering, which has been associated with reflection-asymmetric shapes. The g(2l9Fr) = +0.69 (1) value supports a π1h9/2 shell-model configuration for the ground state. The g(229,231Fr) values support the tentative Iπ(229,231Fr) = (l/2+) spin and point to a πS-11/2 intruder ground-state configuration. [ABSTRACT FROM AUTHOR]

Precision nuclear charge radii measurements in the light-mass region are essential for understanding the evolution of nuclear structure, but their measurement represents a great challenge for experimental techniques. At the Collinear Resonance Ionization Spectroscopy (CRIS) setup at ISOLDE-CERN, a laser frequency calibration and monitoring system was installed and commissioned through the hyperfine spectra measurement of 38-47K. It allowed for the extraction of the hyperfine parameters and isotope shifts with better than 1 MHz precision. These results are in excellent agreement with available literature values and they demonstrate the suitability of the CRIS technique for the study of nuclear observables in light atomic systems. In addition, the spectral line shapes obtained under different conditions were systematically investigated, highlighting the importance of finding optimal conditions, under which the extracted nuclear properties remain unaffected by laser-atom interactions. [ABSTRACT FROM AUTHOR]

Magnetic-dipole and electric-quadrupole moments for 65,67,69,75,79-82Ga are reported using the Collinear Resonance Ionization Spectroscopy (CRIS) technique at the ISOLDE facility, CERN. The moments of 65Ga have been measured for the first time: μ=+1.775(3)μN and Qs=+21.0(15)efm². These results are compared to shell-model calculations using the GXPF1 and JUN45 interactions and the trends of the moments approaching the region of the doubly magic 56Ni are discussed. Additionally, new values for the change in mean-square charge radii for 65Ga and 67Ga allow investigation into the odd-even staggering in the region below N=40. [ABSTRACT FROM AUTHOR]

Nuclear spins and precise values of the magnetic dipole and electric quadrupole moments of the ground states of neutron-rich 73-78Cu isotopes were measured using the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at the CERN On-Line Isotope Mass Separator (ISOLDE) facility. The nuclear moments of the less exotic 73,75Cu isotopes were remeasured with similar precision, yielding values that are consistent with earlier measurements. The moments of the odd-odd isotopes, and 7829Cu (N=49) in particular, are used to investigate excitations of the assumed doubly magic 78Ni core through comparisons with large-scale shell-model calculations. Despite the narrowing of the Z=28 shell gap between N~45 and N=50, the magicity of Z=28 and N=50 is restored toward 78Ni. This is due to weakened dynamical correlations, as clearly probed by the present moment measurements. [ABSTRACT FROM AUTHOR]

The hyperfine spectra of Mn51,53-64 were measured in two experimental runs using collinear laser spectroscopy at ISOLDE, CERN. Laser spectroscopy was performed on the atomic 3d54s²5S/26 → 3d54s 4p P3/26 and ionic 3d5 4s 5S2 → 3d54p 5P3 transitions, yielding two sets of isotope shifts. The mass and field shift factors for both transitions have been calculated in the multiconfiguration Dirac-Fock framework and were combined with a King plot analysis in order to obtain a consistent set of mean-square charge radii which, together with earlier work on neutron-deficient Mn, allow the study of nuclear structure changes from N=25 across N=28 up to N=39. A clear development of deformation is observed towards N=40, confirming the conclusions of the nuclear moments studies. From a Monte Carlo shell-model study of the shape in the Mn isotopic chain, it is suggested that the observed development of deformation is not only due to an increase in static prolate deformation but also due to shape fluctuations and triaxiality. The changes in mean-square charge radii are well reproduced using the Duflo-Zuker formula except in the case of large deformation. [ABSTRACT FROM AUTHOR]

Combined decay and laser spectroscopy measurements of the isotope 124Fr are reported, using the collinear resonance ionization spectroscopy (CRIS) technique at the ISOLDE facility at CERN. For the Iπ=(1-) spin assignment, the g-factor value of g(124Fr)=+0.241(16) corresponds to a relatively pure (π1h9/2 v2g9/2) ground-state configuration. An alternative interpretation with g(124Fr)=+0.144(10), for a (2-) spin assignment suggests a greater contribution of configuration mixing with the v1i11/2 orbital. As the N=126 shell closure is passed, a kink is observed at the δ (r²)213,214 value, which is analogous to the behavior observed in the neighboring isotopic chains. [ABSTRACT FROM AUTHOR]

Collinear laser spectroscopy is performed on the 3079Zn49 isotope at ISOLDE-CERN. The existence of a long-lived isomer with a few hundred milliseconds half-life is confirmed, and the nuclear spins and moments of the ground and isomeric states in 79Zn as well as the isomer shift are measured. From the observed hyperfine structures, spins I=9/2 and I=1/2 are firmly assigned to the ground and isomeric states. The magnetic moment μ (79Zn)=-1.1866(10)μN, confirms the spin-parity 9/2+ with a νg9/2- shell-model configuration, in excellent agreement with the prediction from large scale shell-model theories. The magnetic moment μ (79mZn)=-1.0180(12)μN supports a positive parity for the isomer, with a wave function dominated by a 2h-1p neutron excitation across the N=50 shell gap. The large isomer shift reveals an increase of the intruder isomer mean square charge radius with respect to that of the ground state, δ〈rc²〉79,79m=+0.204(6) fm², providing first evidence of shape coexistence. [ABSTRACT FROM AUTHOR]

We investigate the effects of two-body currents on magnetic dipole moments of medium-mass and heavy nuclei using the valence-space in-medium similarity renormalization group with chiral effective field theory interactions and currents. Focusing on near doubly magic nuclei from oxygen to bismuth, we have found that the leading two-body currents globally improve the agreement with experimental magnetic moments. Moreover, our results show the importance of multishell effects for ^{41}Ca, which suggest that the Z=N=20 gap in ^{40}Ca is not as robust as in ^{48}Ca. The increasing contribution of two-body currents in heavier systems is explained by the operator structure of the center-of-mass dependent Sachs term.

Collinear laser spectroscopy is performed on the nickel isotopes ^{58-68,70}Ni, using a time-resolved photon counting system. From the measured isotope shifts, nuclear charge radii R_{c} are extracted and compared to theoretical results. Three ab initio approaches all employ, among others, the chiral interaction NNLO_{sat}, which allows an assessment of their accuracy. We find agreement with experiment in differential radii δ⟨r_{c}^{2}⟩ for all employed ab initio methods and interactions, while the absolute radii are consistent with data only for NNLO_{sat}. Within nuclear density functional theory, the Skyrme functional SV-min matches experiment more closely than the Fayans functional Fy(Δr,HFB).

Isotope shifts of ^{223-226,228}Ra^{19}F were measured for different vibrational levels in the electronic transition A^{2}Π_{1/2}←X^{2}Σ^{+}. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the electronic density within the radium nucleus. Ab initio quantum chemical calculations are in excellent agreement with experimental observations. These results highlight some of the unique opportunities that short-lived molecules could offer in nuclear structure and in fundamental symmetry studies.

We present the first laser spectroscopic measurement of the neutron-rich nucleus ^{68}Ni at the N=40 subshell closure and extract its nuclear charge radius. Since this is the only short-lived isotope for which the dipole polarizability α_{D} has been measured, the combination of these observables provides a benchmark for nuclear structure theory. We compare them to novel coupled-cluster calculations based on different chiral two- and three-nucleon interactions, for which a strong correlation between the charge radius and dipole polarizability is observed, similar to the stable nucleus ^{48}Ca. Three-particle-three-hole correlations in coupled-cluster theory substantially improve the description of the experimental data, which allows to constrain the neutron radius and neutron skin of ^{68}Ni.