-In the late stages of nuclear burning for massive stars (M > 8 M ⊙ ), the production of neutrino-antineutrino pairs through various processes becomes the dominant stellar cooling mechanism. As the star evolves, the energy of these neutrinos increases and in the days preceding the supernova a significant fraction of emitted electron anti-neutrinos exceeds the energy threshold for inverse beta decay on free hydrogen. This is the golden channel for liquid scintillator detectors because the coincidence signature allows for significant reductions in background signals. We find that the kiloton-scale liquid scintillator detector KamLAND can detect these pre-supernova neutrinos from a star with a mass of 25 M ⊙ at a distance less than 690 pc with 3σ significance before the supernova. This limit is dependent on the neutrino mass ordering and background levels. KamLAND takes data continuously and can provide a supernova alert to the community.

The magnetization reversal process of an ordered Co nanorod array is shown using the images obtained from successive in-field magnetic force microscope (MFM) measurements. The magnetization reversal model is discussed according to local and whole magnetization reversal properties measured by the polar magneto-optical Kerr effect (PMOKE) and an alternating gradient magnetometer (AGM), respectively. Additionally, the dipolar field was probed using in-field MFM measurements. By removing the effect of the dipolar field, an intrinsic switching field distribution (SFD) is shown in a map with a hexagonal array. A detailed study of the dipolar field in ordered nanorod arrays with various diameters and pitches was carried out by numerical calculations.

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The development of magnetic materials with large uniaxial magnetic anisotropy (K u) and high saturation magnetization has attracted much attention in various areas such as high-density magnetic storage, spintronic devices, and permanent magnets. Although FeCo alloys with the body-centred cubic structure exhibit the highest M s among all transition metal alloys, their low K u and coercivity (H c) make them unsuitable for these applications. However, recent first-principles calculations have predicted large K u for the FeCo films with the body-centred tetragonal structure. In this work, we experimentally investigated the hard magnetic properties and magnetic domain structures of nanopatterned FeCo alloy thin films. As a result, a relatively large value of the perpendicular uniaxial magnetic anisotropy K u = 2.1 × 106 J·m−3 was obtained, while the H c of the nanopatterned FeCo layers increased with decreasing dot pattern size. The maximum H c measured in this study was 4.8 × 105 A·m−1, and the corresponding value of μ 0 H c was 0.60 T, where μ 0 represented the vacuum permeability.

Magnetic properties such as magnetization, coercivity, and magnetostriction of rapidly quenched ternary Fe~oo--2--yAlzSiy (0 5 x 5 28.3, 0 5 y 5 lo), Feloo--o--yAlzBy, and Feeloo-zA1,Gey (0 2 x 5 28.3, 0 5 y 5 20.4) are investigated. I n the Fe-Al-Si system, the alloys near Fe,Al,, composition exhibit relatively soft magnetic properties. In the Fe-Al-B system, amorphous structure is achieved in the range 12 5 y 5 25 and best soft magnetic properties, H, = 1.6 A/m, Bs = 1.1 T, pm = 1.4 x lo5, e = 160 pi2 cm are obtained around Fe,,,Al,B,, composition. I n the Fe-Al-Ge system, magnetostriction is nearly zero in the composition range 0 5 x 5 15, 10 5 5 y 5 15. The Fe-rich alloys in Fe-Al-Si and Fe-Al-Ge systems show a high saturation induction above 2.0 T and a small magnetostriction less than 10 x Magnetisohe Eigenschaften, wie Magnetisierung, Koerzitivkraft und Magnetostriktion, von schnell abgeschrecktem, terniirem Feloo-2-vA1,Si-y (0 5 x 5 28,3, 0 5 y 5 lo), FelOo--z--yA1zBy und Feloo-zA1,Gey (0 5 5 5 28,3, 0 5 y 5 20,4) werden untersucht. Im Fe-Al-Si-System zeigt die Legierung in der Niihe der Fe,,Al,,-Zusammensetzung relativ weiche megnetische Eigenschaften. Im Fe-Al-B-System wird die amorphe Struktur im Bereich 12 5 y 5 26 erreicht, und die weichmagnetischen Eigenschaften, H, = 1,6 A/m, B, = 1,l T, pm =