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We report the surface exploration by the lunar rover Yutu that landed on the young lava flow in the northeastern part of the Mare Imbrium, which is the largest basin on the nearside of the Moon and is filled with several basalt units estimated to date from 3.5 to 2.0 Ga. The onboard lunar penetrating radar conducted a 114-m-long profile, which measured a thickness of ∼5 m of the lunar regolith layer and detected three underlying basalt units at depths of 195, 215, and 345 m. The radar measurements suggest underestimation of the global lunar regolith thickness by other methods and reveal a vast volume of the last volcano eruption. The in situ spectral reflectance and elemental analysis of the lunar soil at the landing site suggest that the young basalt could be derived from an ilmenite-rich mantle reservoir and then assimilated by 10-20% of the last residual melt of the lunar magma ocean.volcanic history | Imbrium basin | lunar rover Yutu | lunar penetrating radar | Chang'e-3 mission

Angular analysis of B 0 d → K * µ + µ − decays in p p collisions at √ s = 8 TeV with the ATLAS detector The ATLAS Collaboration An angular analysis of the decay B 0 d → K * µ + µ − is presented, based on proton-proton collision data recorded by the ATLAS experiment at the LHC. The study is using 20.3 fb −1 of integrated luminosity collected during 2012 at centre-of-mass energy of √ s = 8 TeV. Measurements of the K * longitudinal polarisation fraction and a set of angular parameters obtained for this decay are presented. The results are compatible with the Standard Model predictions.Flavour-changing neutral currents (FCNC) have played a significant role in the construction of the Standard Model of particle physics (SM). These processes are forbidden at tree level and can proceed only via loops, hence are rare. An important set of FCNC processes involve the transition of a b-quark to an sµ + µ − final state mediated by electroweak box and penguin diagrams. If heavy new particles exist, they may contribute to FCNC decay amplitudes, affecting the measurement of observables related to the decay under study. Hence FCNC processes allow searches for contributions from sources of physics beyond the SM (hereafter referred to as new physics). This analysis focuses on the decay B 0 d → K * 0 (892)µ + µ − , where K * 0 (892) → K + π − . Hereafter, the K * 0 (892) is referred to as K * and charge conjugation is implied throughout, unless stated otherwise. In addition to angular observables such as the forward-backward asymmetry A FB 1, there is considerable interest in measurements of the charge asymmetry, differential branching fraction, isospin asymmetry, and ratio of rates of decay into dimuon and dielectron final states, all as a function of the invariant mass squared of the dilepton system q 2 . All of these observable sets can be sensitive to different types of new physics that allow for FCNCs at tree or loop level. The BaBar, Belle, CDF, CMS, and LHCb collaborations have published the results of studies of the angular distributions forThe LHCb Collaboration has reported a potential hint, at the level of 3.4 standard deviations, of a deviation from SM calculations [3,4] in this decay mode when using a parameterization of the angular distribution designed to minimise uncertainties from hadronic form factors. Measurements using this approach were also reported by the Belle and CMS Collaborations [6,8] and they are consistent with the LHCb experiment's results and with the SM calculations. This paper presents results following the methodology outlined in Ref. [3] and the convention adopted by the LHCb Collaboration for the definition of angular observables described in Ref. [9]. The results obtained here are compared with theoretical predictions that use the form factors computed in Ref. [10].This article presents the results of an angular analysis of the decay B 0 d → K * µ + µ − with the ATLAS detector, using 20.3 fb −1 of pp collision data at a centre-of-mass energy √ s = 8 TeV delivered by the Large Hadron Collider (LHC...

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The distribution of water in the Moon's interior carries key implications for the origin of the Moon 1 , the crystallisation of the lunar magma ocean 2 , and the duration of lunar volcanism 2 . The Chang'E-5 (CE5) mission returned the youngest mare basalt samples, dated at ca. 2.0 billion years ago 3 , from the northwestern Procellarum KREEP Terrane (PKT), providing a probe into the spatio-temporal evolution of lunar water. Here we report the water abundance and hydrogen isotope composition of apatite and ilmenite-hosted melt inclusions from CE5 basalts, from which we derived a maximum water abundance of 370 ± 30 g.g -1 and a δD value (-330 ± 160‰) for their parent magma. During eruption, hydrogen degassing led to an increase in the D/H ratio of the residual melts up to δD values of 300-900‰. Accounting for low degrees of mantle partial melting followed by extensive magma fractional crystallisation 4 , we estimate a maximum mantle water abundance of 2-6 g.g -1 , which are too low for water contents alone to account for generating the Moon's youngest basalts. Such modest water abundances for the lunar mantle are at the lower end of those estimated from mare basalts that erupted from ca. 4.0-2.8 Ga 5, 6 , suggesting the mantle source of CE5 basalts dried up by ca. 2.0 Ga through previous melt extraction from the PKT mantle during prolonged volcanic activity.Water abundance in the lunar mantle places strict constraints on high-temperature processes, including the Moon-forming giant impact 1 , the ensuing crystallisation of the lunar magma ocean 7 , and the longevity of volcanism on the Moon 2 . Based upon the analyses carried out since the Apollo era, the Moon was long thought to be an anhydrous body. Advances in in situ analytical techniques over the past decade have allowed analysis of water abundances at micro-scale in various lunar samples, including in olivine-and pyroxene-hosted melt inclusions in mare basalts [8][9][10][11][12] , apatite in mare basalts and highlands samples [13][14][15][16][17][18][19][20] , pyroclastic glass beads 21, 22 , and

Zircons and apatites in clasts and matrix from the Martian breccia NWA 7034 are well documented, timing ancient geologic events on Mars. Furthermore, in this study, zircon trace elemental content, apatite volatile content, and apatite volatile isotopic compositions measured in situ could constrain the evolution of those geologic events. The U‐Pb dates of zircons in basalt, basaltic andesite, trachyandesite igneous clasts, and the matrix are similar (4.4 Ga) suggesting intense volcanism on ancient Mars. However, two metamict zircon grains found in the matrix have an upper intercept date of ~4465 Ma in crystalline, whereas amorphous areas have a lower intercept date of 1634 ± 93 Ma. The younger date is consistent with the date of apatites (1530 ± 65 Ma), suggesting a metamorphic event that completely reset the U‐Pb system in both the amorphous areas of zircon and all apatites. δD values in all apatites negatively correlate with water content in a two‐endmember mixing trend. The D (δD up to 2459‰) and 37Cl heavy core (3.8‰) of a large apatite grain suggest a D‐, 37Cl‐rich fluid during the metamorphic event ~1.6 Ga ago, consistent with the trace elements Y, Hf and Ti and P in zircons. The fluid was also therefore P‐rich. The D‐, 37Cl‐poor H2O‐rich rim (<313‰) suggests the degassing of water from the Martian Cl‐poor interior at a later time. This D‐, 37Cl‐poor Martian mantle reservoir could have derived from volcanic intrusions postdating the younger metamorphic event recorded in NWA 7034.

Apatite and silicate glasses share the same water content calibration curves in isotope modes where water was determined from the H− intensity regardless of multicollection or peak jumping. In contrast, the slope of apatite significantly differs from that of silicate glasses in element mode where OH− was counted for the water content.

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