Two pairs of positive-and negative-parity doublet bands together with eight strong electric dipole transitions linking their yrast positive-and negative-parity bands have been identified in 78 Br. They are interpreted as multiple chiral doublet bands with octupole correlations, which is supported by the microscopic multidimensionally-constrained covariant density functional theory and triaxial particle rotor model calculations. This observation reports the first example of chiral geometry in octupole soft nuclei. DOI: 10.1103/PhysRevLett.116.112501 Spontaneous symmetry breaking is a fundamental concept in nature. As a many-body quantum system, the atomic nucleus carries a wealth of information on fundamental symmetries and symmetry breaking. As one example, chiral symmetry breaking in atomic nuclei has attracted considerable attention and intensive discussion since it was first predicted by Frauendorf and Meng [1]. They pointed out that, in the intrinsic frame of the rotating triaxial nucleus, the total angular momentum vector may lie outside the three principal planes, referred to as chiral geometry. The spontaneous chiral symmetry breaking in the laboratory frame may give rise to pairs of nearly degenerate ΔI ¼ 1 bands with the same parity, i.e., chiral doublet bands. Such chiral doublet bands were first observed in N ¼ 75 isotones [2]. So far, more than 30 experimental candidates have been reported in the A ∼ 80, 100, 130, and 190 mass regions [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].Based on constrained triaxial covariant density functional theory (CDFT) calculations, it has been suggested that multiple chiral doublet (MχD) bands can exist in a single nucleus [21][22][23][24][25][26]. The theoretical prediction of MχD bands stimulated lots of experimental efforts [27][28][29][30][31]. The first experimental evidence for MχD bands was reported in 133 Ce [27], which confirmed the manifestation of triaxial shape coexistence in this nucleus. Later, Kuti et al. reported a novel type of MχD bands with the same configuration in 103 Rh [29], which showed that chiral geometry can be robust against the increase of the intrinsic excitation energy.Compared to the A ∼ 130 and 100 mass regions, the A ∼ 80 mass region is a relatively new and less studied territory for the investigation of chiral symmetry breaking in rotating nuclei, with only one report of chiral doublet bands based on the πg 9=2 ⊗ νg 9=2 configuration in odd-odd 80 Br [18]. In 78 Br, the πg 9=2 ⊗ νg 9=2 band was suggested to have an obvious triaxial shape [32], which is suitable for the construction of chiral doublet bands.

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In this paper, we report the effect of soda lime substrate deposition temperature (T s) on the crystal structure and the metal insulator transition of VO 2 thin films. Samples were deposited at substrate deposition temperature ranging from 450 to 600 0 C by pulsed-laser deposition and characterized by x-ray diffraction and UV-VIS spectrophotometer. At a substrate temperature of 550°C, the VO 2 (100) reflection dominate the spectrum showing a change in crystalline grains orientation. The highest transition temperatures of 74 o C with the lowest hysteresis width of 11 o C were obtained on the same sample grown at a substrate deposition temperature of 500 o C and also corresponding to the largest grains size of a value of 350 nm.

A search for isomeric states was performed in the nucleus 140 60 Nd 80 using in-beam γ -ray spectroscopy and the 126 Te( 18 O,4n) reaction. Prompt and delayed γ -ray coincidences were measured with the AFRODITE spectrometer using the pulsed beam delivered by the Separated Sector Cyclotron of iThemba LABS. One new isomer was identified, with spin-parity I π = 20 + and lifetime T 1/2 400 ns, at an excitation energy E x = 7430 keV. The lifetime of the 10 + isomer at E x = 3619 keV was determined to be 32.9(1.8) ns, confirming the previously reported value. The configuration of the I π = 20 + isomer is assigned based on configuration-dependent cranked Nilsson-Strutinsky (CNS) calculations as a state π (d 5/2 g 7/2 ) −4 10 + ⊗ν (h −2 11/2 ) 10 + , with the spin vectors of the six holes in the 146 64 Gd 82 core fully aligned.