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Pulsating auroras (PsAs) are thought to be generated by precipitating electrons scattered by lower‐band chorus (LBC) waves near the magnetic equator. One‐to‐one correlation between the LBC intensity and the PsA intensity has been reported. Electrostatic electron cyclotron harmonic (ECH) waves can also scatter electrons. However, direct correlation between ECH and PsA has not been reported yet. In this study, using a coordinated Exploration of energization and Radiation in Geospace (Arase) satellite and ground‐based imager observation, we report that not only LBC but also ECH have correlation with PsA. We estimated the precipitating electron energy by assuming that the time lag when the cross‐correlation coefficient became the highest was travel time of electrons from the modulation region. We found that the estimated energies show reasonable values as the cyclotron resonance energy of each wave.

Low Earth orbit satellites frequently encounter Pc1 pulsations, but most have been observed with limited latitudinal extent or short lifetime. In this study we analyze two large‐scale Pc1 pulsations (both latitudinally wide and long‐lasting) generated by ionospheric ducting effect using Swarm and ground magnetometers on 25 June and 3 September 2015. Swarm observed the 25 June pulsations on both dayside and nightside during the storm time substorm (a strong geomagnetic storm on 23 June with \(D_{st} = − 204~nT\)). We found the Pc1 pulsations were pervasive in both magnetic local time sectors of dayside and nightside for at least 2 hr. Another large Pc1 pulsation on 3 September was observed during a nonstorm substorm period. We conclude that (1) ionospheric ducting can transmit Pc1 waves to a wide range of L shells, (2) geomagnetic storm is not a prerequisite for such large‐scale ducting, and (3) wave intensity can abruptly decrease across sharp gradients in the ionospheric plasma density.

The severity of metabolic syndrome depends on the degree of insulin resistance. However, currently there is no adequate clinical marker for quantitative analysis of insulin resistance. A small quantity of lipoprotein lipase (LPL) protein, which is an inactive form and commonly called 'preheparin LPL mass', exists in serum and is detected by a sensitive immunoassay system. Recent studies have reported the clinical significance of serum preheparin LPL mass levels in various aspects. For example, preheparin LPL mass is negatively related to serum triglyceride and positively related to HDL-cholesterol, is low in type 2 diabetes mellitus, is increased by administration of insulin sensitizer, and shows an inverse relationship with visceral adiposity. Furthermore, preheparin LPL mass level is significantly lower in patients with coronary atherosclerosis compared to patients with no lesion, and correlates negatively with the severity of these lesions. From these reports, preheparin LPL mass may be considered to be the most important quantitative indicator of insulin resistance of the whole body.

One-neutron knockout from 24 O leading to the first excited state in 23 O has been measured for a proton target at a beam energy of 62 MeV/nucleon. The decay energy spectrum of the neutron unbound state of 23 O was reconstructed from the measured four momenta of the 22 O fragment and emitted neutron. A sharp peak was found at Edecay=50±3 keV , corresponding to an excited state in 23 O at 2.78±0.11 MeV , as observed in previous measurements. The longitudinal momentum distribution for this state was consistent with d -wave neutron knockout, providing support for a Jπ assignment of 5/2+ . The associated spectroscopic factor was deduced to be C2S(0d5/2)=4.1±0.4 by comparing the measured cross section ( σ−1nexp=61±6 mb ) with a distorted wave impulse approximation calculation. Such a large occupancy for the neutron 0d5/2 orbital is in line with the N=16 shell closure in 24 O.

Open Access; International audience; One-neutron knockout from 24O leading to the first excited state in 23O has been measured for a proton target at a beam energy of 62 MeV/nucleon. The decay energy spectrum of the neutron unbound state of 23O was reconstructed from the measured four momenta of the 22O fragment and emitted neutron. A sharp peak was found at Edecay=50±3 keV, corresponding to an excited state in 23O at 2.78±0.11 MeV, as observed in previous measurements. The longitudinal momentum distribution for this state was consistent with d -wave neutron knockout, providing support for a Jπ assignment of 5/2+. The associated spectroscopic factor was deduced to be C2S(0d5/2)=4.1±0.4 by comparing the measured cross section (View the MathML source) with a distorted wave impulse approximation calculation. Such a large occupancy for the neutron 0d5/2 orbital is in line with the N=16 shell closure in 24O.The neutron drip-line nucleus 24O, which has been studied extensively in recent years [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13] and [14], is now considered a doubly-closed-shell nucleus. In particular, the high excitation energy of the first 2+ state [7] and small quadrupole transition parameter [14] are strong indicators of an N=16 spherical shell closure. In addition, Kanungo et al. [8] found a large spectroscopic factor – C2S(1s1/2)=1.74±0.19 – for one-neutron knockout from 24O reflecting an almost complete occupancy of the 1s1/2 orbital.In this Letter we report on the spectroscopic factor for d5/2 neutron removal from 24O. The first excited state of 23O, which is neutron unbound [15], [13] and [16], was populated by one-neutron knockout from 24O with a proton target. The excitation energy, cross section, and longitudinal momentum distribution were determined and allowed the 0d5/2 neutron-hole nature of this state to be identified. The large spectroscopic factor deduced for this state is in line with the N=16 shell closure in 24O.The experiment was performed at the RIPS facility [17] at RIKEN. The experimental setup has been described in Refs. [14] and [18], and is depicted in Fig. 1. The secondary 24O beam was produced using a 1.5 mm-thick Be production target and a 95 MeV/nucleon 40Ar primary beam of ∼40 pnA. The average intensity of the 24O beam was ∼4 particles/sec. The momentum of the secondary beam was determined particle-by-particle by measuring the position at the dispersive focus F1 of RIPS with a parallel plate avalanche counter. The energy loss (ΔE ) and time-of-flight (TOF) were measured using 350 μm-thick silicon and 500 μm-thick plastic scintillator detectors, respectively, at the achromatic focus F2. The liquid-hydrogen (LH2) target [19] was installed at the achromatic focus F3. The effective target thickness and the mid-target energy of 24O were 159±3 mg/cm2 and 62 MeV/nucleon, respectively. The 24O beam incident on the target was tracked particle-by-particle by using two multi-wire drift chambers installed just upstream of the target. The target was surrounded by an array consisting of 48 NaI(Tl) crystals (DALI) to detect γ rays from de-excitation of the fragments.