The geochemical characteristics of melt inclusions and their host olivines provide important information on the processes that create magmas and the nature of their mantle and crustal source regions. We report chemical compositions of melt inclusions, their host olivines and bulk rocks of Xindian basalts in Chifeng area, North China Craton. Compositions of both bulk rocks and melt inclusions are tholeiitic. Based on petrographic observations and compositional variation of melt inclusions, the crystallizing sequence of Xindian basalts is as follows: olivine (at MgO [ *5.5 wt%), plagioclase (beginning at MgO = *5.5 wt%), clinopyroxene and ilmenite (at MgO \ 5.0 wt%). High Ni contents and Fe/Mn ratios, and low Ca and Mn contents in olivine phenocrysts, combining with low CaO contents of relatively high MgO melt inclusions (MgO [ 6 wt%), indicate that Xindian basalts are possibly derived from a pyroxenite source rather than a peridotite source. In the CS-MS-A diagram, all the high MgO melt inclusions (MgO [ 6.0 wt%) project in the field between garnet ? clinopyroxene ? liquid and garnet ? clinopyroxene ? orthopyroxene ? liquid near 3.0 GPa, further suggesting that residual minerals are mainly garnet and clinopyroxene, with possible presence of orthopyroxene, but without olivine. Modeling calculations using MELTS show that the water content of Xindian basalts is 0.3-0.7 wt% at MgO = 8.13 wt%. Using 20-25 % of partial melting estimated by moderately incompatible element ratios, the water content in the source of Xindian basalts is inferred to be C450 ppm, much higher than 6-85 ppm in dry lithospheric mantle. The melting depth is inferred to be *3.0 GPa, much deeper than that of tholeiitic lavas (\2.0 GPa), assuming a peridotite source with a normal mantle potential temperature. Such melting depth is virtually equal to the thickness of lithosphere beneath Chifeng area (*100 km), suggesting that Xindian basalts are derived from the asthenospheric mantle, if the lithospheric lid effect model is assumed.

The18 Ne(α,p) 21 Na reaction is thought to be one of the key breakout reactions from the hot CNO cycles to the rp-process in type I x-ray bursts. In this work, the resonant properties of the compound nucleus 22 Mg have been investigated by measuring the resonant elastic scattering of 21 Na+p. An 89 MeV 21 Na radioactive beam delivered from the CNS Radioactive Ion Beam Separator bombarded an 8.8 mg/cm 2 thick polyethylene (CH2)n target. The 21 Na beam intensity was about 2×10 5 pps, with a purity of about 70% on target. The recoiled protons were measured at the center-of-mass scattering angles of θc.m.≈175.2• , 152.2 • , and 150.5• by three sets of ∆E-E telescopes, respectively. The excitation function was obtained with the thick-target method over energies Ex( 22 Mg)=5.5-9.2 MeV. In total, 23 states above the proton-threshold in 22 Mg were observed, and their resonant parameters were determined via an R-matrix analysis of the excitation functions. We have made several new J π assignments and confirmed some tentative assignments made in previous work. The thermonuclear 18 Ne(α,p) 21 Na rate has been recalculated based on our recommended spin-parity assignments. The astrophysical impact of our new rate has been investigated through one-zone postprocessing x-ray burst calculations. We find that the 18 Ne(α,p) 21 Na rate significantly affects the peak nuclear energy generation rate, reaction fluxes, as well as the onset temperature of this breakout reaction in these astrophysical phenomena.

High-spin states in 183 Au have been studied experimentally using the 159 Tb( 29 Si, 5n) 183 Au reaction at a beam energy of 140 MeV. Three-or higherfold γ -ray coincidences have been measured using the detector array of GASP. The level scheme of 183 Au was revised and extended. A rotational band proposed as the unfavored signature branch of the πi 13/2 band has been observed for 183 Au. Interaction properties between the two negative-signature bands of the πh 9/2 -πf 7/2 system have been discussed for the light odd-A Au nuclei.The high spin states for the odd-A Au nuclei have been extensively investigated [1][2][3][4][5][6][7][8][9][10][11][12]. The level structure in light odd-A Au nuclei consists mainly of prolate rotational bands, and the intruder 1 2 [541](h 9/2 ) and 1 2 [660](i 13/2 ) bands dominate the yrast line [4][5][6][7]. In Ref.[5], a variable moment of inertia fit was carried out for the 1 2 [660] bands in the odd-A Au nuclei, and empirical values of the deformation were subsequently deduced. The extracted deformations were maximized at neutron numbers of 98 and 100, corresponding to 177 Au and 179 Au. This result is contradictory to the total Routhian surface (TRS) prediction, which placed the maximum in deformation near midshell [5]. Due to the large signature splitting, the unfavored signature branch of the πi 13/2 band has not been observed for odd-A Au nuclei, except for 181 Au. As a by-product of the experiment dedicated to the study of 184 Au, the high-spin level scheme of 183 Au [4] has been revised, and the unfavored signature branch of πi 13/2 band in 183 Au has been observed for the fist time.The high-spin states in 183 Au were populated via the 159 Tb( 29 Si, 5n) 183 Au reaction at a bombarding energy of 140 MeV. The 29 Si beam of 8 pnA was provided by the accelerator complex of the Tandem-XTU and ALPI at the Laroratori Nazionali di Legnero, Italy, and focused onto a natural metallic 159 Tb foil of 2 mg/cm 2 thickness. The target was backed with gold of about 5 mg/cm 2 thickness to avoid the Doppler shift of emitting γ rays. In-beam γ rays were detected by the detector array of GASP, which consists of 40 Compton suppressed large-volume Ge detectors and a multiplicity filter of 80 BGO elements. The detectors were calibrated with 60 Co, 133 Ba, and 152 Eu standard sources; the average resolution was about 2.2 keV at full width at half maximum for the 1332.5-keV line. Events were collected when at least three suppressed Ge and two inner multiplicity filter detectors were fired. A total of 2 × 10 8 events was accumulated, and about 15% of the coincidence events was 183 Au. After gain matching, the coincidence events were sorted into fully symmetrized matrices and cubes for offline analysis.γ -ray coincidence relationships have been analyzed carefully using the matrices and cubes, and a representative double-gated coincidence spectrum is given in Fig. 1, showing the quality of the data. The level scheme of 183 Au has been proposed and shown in Fig. 2. The widths of the arrows represent the r...

We report the energy-resolved broadband timing analysis of the black hole X-ray transient MAXI J1631-479 during its 2019 outburst from February 11 to April 9, using data from the Insight−Hard X-ray Modulation Telescope (Insight-HXMT), which caught the source from its hard-intermediate state to the soft state. Thanks to the large effective area of Insight-HXMT at high energies, we are able to present the energy dependence of fast variability up to ∼100 keV. Type-C quasi-periodic oscillations (QPOs) with a frequency varying between 4.9 and 6.5 Hz are observed in the 1–100 keV energy band. While the QPO fractional rms increases with photon energy from 1 keV to ∼10 keV and remains more or less constant from ∼10 keV to ∼100 keV, the rms of the flat-top noise first increases from 1 keV to ∼8 keV and then drops to less than 0.1% above ∼30 keV. We suggest that the disappearance of the broadband variability above 30 keV could be caused by the nonthermal acceleration in the Comptonizing plasma. At the same time, the QPOs could be produced by the precession of either a small-scale jet or a hot inner flow model.

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High-spin states in 190 Tl have been studied experimentally by using the 160 Gd( 35 Cl,5n) fusion-evaporation reaction at beam energies of 167 and 175 MeV. A rotational band built on the πh 9/2 ⊗ νi 13/2 configuration with oblate deformation has been established for 190 Tl. Spin values are assigned by adopting the results from α-γ decay work for 194 Bi found in the literature. With the configuration and spin-parity assignments, the low-spin signature inversion has been revealed for the πh 9/2 ⊗ νi 13/2 oblate band in 190 Tl. It is the first experimental observation of low-spin signature inversion for a band associated with the oblate πh 9/2 ⊗ νi 13/2 configuration. The low-spin signature inversion for the oblate πh 9/2 ⊗ νi 13/2 band can be interpreted by the two-quasiparticle-plus-rotor model including a J-dependent p-n residual interaction.

We present a spectral study of the black hole candidate MAXI J1348−630 during its 2019 outburst, based on monitoring observations with Insight-HXMT and Swift. Throughout the outburst, the spectra are well fitted with power-law plus disk-blackbody components. In the soft-intermediate and soft states, we observed the canonical relation L ∝ T in 4 between disk luminosity L and peak color temperature T in, with a constant inner radius R in (traditionally identified with the innermost stable circular orbit). At other stages of the outburst cycle, the behavior is more unusual, inconsistent with the canonical outburst evolution of black hole transients. In particular, during the hard rise, the apparent inner radius is smaller than in the soft state (and increasing), and the peak color temperature is higher (and decreasing). This anomalous behavior is found even when we model the spectra with self-consistent Comptonization models, which take into account the upscattering of photons from the disk component into the power-law component. To explain both anomalous trends at the same time, we suggest that the hardening factor for the inner-disk emission was larger than the canonical value of ≈1.7 at the beginning of the outburst. A more physical trend of radii and temperature evolution requires a hardening factor evolving from ≈3.5 at the beginning of the hard state to ≈1.7 in the hard-intermediate state. This could be evidence that the inner disk was in the process of condensing from the hot, optically thin medium and had not yet reached a sufficiently high optical depth for its emission spectrum to be described by the standard optically thick disk solution.

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