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Dissociative tunneling ionization of tetrafluoromethane (CF4) in circularly polarized ultrashort intense laser fields (35 fs, 0.8 × 1014 W cm−2, 1035 nm), CF4 → CF4+ + e− → CF3+ + F + e−, has been studied by three-dimensional electron-ion coincidence momentum imaging. The photoelectron angular distribution in the recoil frame revealed that the dissociative tunneling ionization occurs efficiently when the laser electric field points from F to C. The obtained results are qualitatively consistent with the theoretical predictions by the weak-field asymptotic theory (WFAT) for tunneling ionization from the highest and next-highest occupied molecular orbitals, HOMO (1t1), and HOMO−1 (4t2), respectively. On the other hand, the angular distribution shows clear dependences on the polarization helicity, indicating that the breaking of the C-F bonds is sensitive to the helicity of the multicycle circularly polarized laser fields.

The mantle section of the central Palawan Ophiolite (CPO) in western Philippines is dominantly composed of dunites and harzburgites. Basal lherzolites and harzburgites juxtaposed with the metamorphic sole of the CPO are also exposed within the vicinity of Ulugan Bay, Puerto Princesa. These basal peridotites provide novel information regarding the processes transpiring in the upper mantle during the evolution of this preserved oceanic lithosphere. The Nasuduan lherzolite is characterized by low Cr# of spinel and high concentrations of REEs in clinopyroxenes. The Oyster Bay lherzolite displays similar fertile characteristics and occurs with harzburgites. Both contain fine-grained and interstitial clinopyroxenes derived from interstitial melts. Tremolite and talc in the Oyster Bay lherzolite and harzburgite and in other CPO harzburgites are attributed to slab-fluid metasomatism. Harzburgites and dunites from Bentoan Beach and other CPO harzburgites have high spinel Cr# and low clinopyroxene REE concentrations. These indicate that these peridotites have undergone extensive degrees of melting facilitated by fluids. The petrological and geochemical signatures of the CPO peridotites record the transition of a supra-subduction zone from back-arc spreading, incipient subduction, to the obduction of an ancient oceanic lithosphere.

The escape fraction of Lyman-continuum (LyC) photons ($f_{esc}$) is a key parameter for determining the sources of cosmic reionization at $z\geq 6$. At these redshifts, owing to the opacity of the intergalactic medium, the LyC emission cannot be measured directly. However, LyC leakers during the epoch of reionization could be identified using indirect indicators that have been extensively tested at low and intermediate redshifts. These include a high [OIII]/[OII] flux ratio, high star-formation surface density, and compact sizes. In this work, we present observations of 29 $4.5 \leq z \leq 8$ gravitationally lensed galaxies in the Abell 2744 cluster field. From a combined analysis of JWST-NIRSpec and NIRCam data, we accurately derived their physical and spectroscopic properties: our galaxies have low masses $(\log(M_\star)\sim 8.5)$, blue UV spectral slopes ($\beta \sim -2.1$), compact sizes ($r_e \sim 0.3-0.5$ kpc), and high [OIII]/[OII] flux ratios. We confirm that these properties are similar to those characterizing low-redshift LyC leakers. Indirectly inferring the fraction of escaping ionizing photons, we find that more than 80% of our galaxies have predicted $f_{esc}$ values larger than 0.05, indicating that they would be considered leakers. The average predicted $f_{esc}$ value of our sample is 0.12, suggesting that similar galaxies at $z\geq 6$ have provided a substantial contribution to cosmic reionization., Comment: Accepted for publication in the 4. Extragalactic astronomy section of A&A, 12 pages, 8 figures

The extent of partial melting of peridotites is a function of temperature, pressure, and fluid supply. Understanding the petrogenesis of ultra-depleted peridotites is important for elucidating mantle potential temperature and the role of water in the mantle. We analyzed the major and trace element compositions of ultra-depleted peridotites from the Kamuikotan zone, Japan. Geochemical models were then generated to constrain the melting conditions and their relation to boninitic melts. The peridotites are characterized by minerals with high Mg/Fe and Cr/Al ratios, and olivine and orthopyroxene with low Ti and Y contents. The mineral compositions suggest that these peridotites are among the most depleted peridotites on Earth. Orthopyroxene compositions characterized by Zr and Sr enrichments relative to Ti and Y depletion cannot be solely explained by melt extraction from typical mantle compositions. Modeling of influx melting reproduces orthopyroxene trace element compositions of ultra-depleted harzburgites formed after high degrees (>30%) of slab-fluid influx melting at a low influx rate and melt fraction. The instantaneous fractional melts equilibrated with residues produced by the melting model and the melts, which equilibrated with amphiboles have similar trace elements patterns as boninites. However, the instantaneous fractional melts have low trace element abundances indicating that ultra-depleted harzburgites are residues after extraction of refractory melts. Boninites are probably accumulated melts formed during the melting processes, or fractionated melt from the instantaneous fractional melts. High temperatures (>1350°C) and continuous fluid supply are key to the formation of ultra-depleted peridotites and boninites during subduction initiation.

We present new observations of MRG-M2129, a quiescent galaxy at z = 2.15, with the Atacama Large Millimeter/submillimeter Array (ALMA). With the combination of the effect of gravitational lensing by the foreground galaxy cluster and the angular resolution provided by ALMA, our data reveal 1.2 mm continuum emission at ∼130 pc angular resolution. Compact dust continuum is detected at 7.9σ in the target but displaced from its stellar peak position by 62 ± 38 mas, or ∼169 ± 105 pc in the source plane. We find a considerably high dust-to-stellar mass ratio, 4 × 10−4. From nondetection of the [C i] 3P2 → 3P1 line, we derive 3σ upper limits on the molecular gas-to-dust mass ratio δ GDR < 60 and the molecular gas-to-stellar mass ratio f H2 < 2.3%. The derived δ GDR is ≳2× smaller than the typical value assumed for quiescent galaxies in the literature. Our study supports the idea that there exists a broad range of δ GDR and urges submillimeter follow-up observations of quenching/recently quenched galaxies at similar redshifts. Based on the inferred low δ GDR and other observed properties, we argue that the central black hole is still active and regulates star formation in the system. Our study exhibits a rare case of a gravitationally lensed type 2 QSO harbored by a quiescent galaxy.

We exploit James Webb Space Telescope (JWST) NIRCam observations from the GLASS-JWST-Early Release Science program to investigate galaxy stellar masses at z>7. We first show that JWST observations reduce the uncertainties on the stellar mass by a factor of at least 5-10, when compared with the highest quality data sets available to date. We then study the UV mass-to-light ratio, finding that galaxies exhibit a two orders of magnitude range of M/L_UV values for a given luminosity, indicative of a broad variety of physical conditions and star formation histories. As a consequence, previous estimates of the cosmic star stellar mass density - based on an average correlation between UV luminosity and stellar mass - can be biased by as much as a factor of ~6. Our first exploration demonstrates that JWST represents a new era in our understanding of stellar masses at z>7, and therefore of the growth of galaxies prior to cosmic reionization., Comment: Accepted for publication in ApJL. Revised analysis with updated NIRCam calibrations (minor changes, conclusions unaffected)

BackgroundHealthy older adults show a decrease in motor learning capacity as well as in working memory (WM) performance. WM has been suggested to be involved in motor learning processes, such as sequence learning. Correlational evidence has shown the involvement of the fronto-parietal network (FPN), a network underlying WM processes, in motor sequence learning. However, causal evidence is currently lacking. Non-invasive brain stimulation (NIBS) studies have focused so far predominantly on motor related areas to enhance motor sequence learning while areas associated with more cognitive aspects of motor learning have not yet been addressed.HypothesisIn this study, we aim to provide causal evidence for the involvement of WM processes and the underlying FPN in successful motor sequence learning by using a theta transcranial alternating current stimulation (tACS) paradigm targeting the FPN during motor sequence learning.MethodsIn a cohort of 20 healthy older adults, we applied bifocal tACS in the theta range to the FPN during a sequence learning task. With the use of a double-blind, cross-over design, we tested the efficacy of active compared with sham stimulation. Two versions of the motor task were used: one with high and one with low WM load, to explore the efficacy of stimulation on tasks differing in WM demand. Additionally, the effects of stimulation on WM performance were addressed using an N-back task. The tACS frequency was personalized by means of EEG measuring the individual theta peak frequency during the N-back task.ResultsThe application of personalized theta tACS to the FPN improved performance on the motor sequence learning task with high WM load (p p p =.03) during the task with high WM load. In addition, the stimulation paradigm improved performance on the N-back task for the 2-back task (p = .013), but not for 1-back and 3-back.ConclusionMotor sequence learning can be enhanced with the use of personalized bifocal theta tACS to the FPN when WM load is high. This indicates that the efficacy of this stimulation paradigm is dependent on the cognitive demand during the learning task and provides further causal evidence for the critical involvement of WM processes and the FPN in motor sequence learning in healthy older adults. These findings open new exciting possibilities to counteract the age-related decline in motor learning capacity and WM performance.

3C186, a radio-loud quasar at $z=1.0685$, was previously reported to have both velocity and spatial offsets from its host galaxy, and has been considered as a promising candidate for a gravitational wave recoiling black hole triggered by a black hole merger. Another possible scenario is that 3C186 is in an on-going galaxy merger, exhibiting a temporary displacement. In this study, we present analyses of new deep HST/WFC3-IR and ACS images, aiming to characterize the host galaxy and test this alternative scenario. We carefully measure the light-weighted center of the host and reveal a significant spatial offset from the quasar core ($11.1\pm0.1$kpc). The direction of the confirmed offset aligns almost perpendicularly to the radio jet. We do not find evidence of a recent merger, such as a young starburst in disturbed outskirts, but only marginal light concentration in F160W at $\sim30$kpc. The host consists of matured ($>200$Myr) stellar populations and one compact star-forming region. We compare with hydro-dynamical simulations and find that those observed features are consistently seen in late-stage merger remnants. Taken together, those pieces of evidence indicate that the system is not an on-going/young merger remnant, suggesting that the recoiling black hole scenario is still a plausible explanation for the puzzling nature of 3C186., Accepted for publication in ApJ. 14 pages, 8 figures, 2 tables

The GLASS-JWST Early Release Science (hereafter GLASS-JWST-ERS) Program will obtain and make publicly available the deepest extragalactic data of the ERS campaign. It is primarily designed to address two key science questions, namely, “what sources ionized the universe and when?” and “how do baryons cycle through galaxies?”, while also enabling a broad variety of first look scientific investigations. In primary mode, it will obtain NIRISS and NIRSpec spectroscopy of galaxies lensed by the foreground Hubble Frontier Field cluster, Abell 2744. In parallel, it will use NIRCam to observe two fields that are offset from the cluster center, where lensing magnification is negligible, and which can thus be effectively considered blank fields. In order to prepare the community for access to this unprecedented data, we describe the scientific rationale, the survey design (including target selection and observational setups), and present pre-commissioning estimates of the expected sensitivity. In addition, we describe the planned public releases of high-level data products, for use by the wider astronomical community.

Wide Field Slitless Spectroscopy (WFSS) provides a powerful tool for detecting strong line emission in star forming galaxies (SFGs) without the need for target pre-selection. As part of the GLASS-JWST-ERS program, we leverage the near-infrared wavelength capabilities of NIRISS ($1-2.2\mu$m) to observe rest-optical emission lines out to $\rm{z}\sim 3.4$, to a depth and with a spatial resolution higher than ever before (H$\alpha$ to z750$A in our sample to be $12\%$. We determine a strong correlation between the measured H$\beta$ and [OIII]$\lambda5007$ EWs, supporting that the high [OIII]$\lambda5007$ EW objects require massive stars in young stellar populations to generate the high energy photons needed to doubly ionise oxygen. We extracted spectra for objects up to 2 mag fainter in the near-infrared than previous WFSS studies with the Hubble Space Telescope. Thus, this work clearly highlights the potential of JWST/NIRISS to provide high quality WFSS datasets in crowded cluster environments., Comment: 9 pages, 3 figures, submitted to APJL

We study star formation and metallicity enrichment histories of 24 massive galaxies at 1.6 < z < 2.5. Deep slitless spectroscopy + imaging data set collected from multiple HST surveys allows robust determination of their SEDs. Our new SED modeling with no functional assumptions on star formation histories revels that 1. most of the sample galaxies have already formed >50% of their extant masses ∼1.5 Gyr before the time of observed redshifts, with a trend where more massive galaxies form earlier, 2. most of our galaxies already have stellar metallicities compatible with those of local early-type galaxies, and 3. inferred metallicities are on average ∼ 0.25 dex higher than observed gas-phase metallicities of star forming galaxies at the time of their formation. Continuation of low-level star formation, rather than abrupt termination of star forming activity, may explain the observed gap of metallicities.

We developed practical high school educational material for a stereo vision autonomous simple and compact robot, which has not been previously reported until now in the technical education field. The results of this program are summarized as follows: The opinions of the high school students, which can be verified from the pre-program questionnaire, and the final questionnaire was `We never had an opportunity to touch the vision technology until now, which is considered to become an important future technology'. This opinion is almost similar to that expressed by both the first and second grade students from an undergraduate engineering university; this is because both the technical knowledge and the educational environment are almost the same as that of the technical high school students. This educational program can impart practical education including vision technology fundamentals, which have a far-reaching impact. The salient features of this program can be summarized as follows: 1) As the educational program was formulated to encourage the pleasure of experimenting with robot technology in practical exercises, it motivated the students positively. 2) This program was intended to cultivate each basic technology and technological capability, interest and awareness among the students. 3) Furthermore, the educational materials also attained the educational goal as set in the beginning. As for the student's opinion regarding the vision sensor, the application of vision technology in robotics is important in the field of robot research. However, the conventional educational materials use infrared sensors for basic technical education, which is not an actual vision sensor. This vision sensor module holds significant potential in education since the module is compact, has high usability and is very affordable. Visual information processing has long been researched; however, educational programs that use this

We publicly release the spectroscopic and photometric redshift catalog of the sources detected with Chandra in the field of the $z$=6.3 quasar SDSS J1030+0525. This is currently the fifth deepest X-ray field, and reaches a 0.5-2 keV flux limit $f_{\rm 0.5-2}$=6$\times$10$^{-17}$ erg s$^{-1}$ cm$^{-2}$. By using two independent methods, we measure a photometric redshift for 243 objects, while 123 (51%) sources also have a spectroscopic redshift, 110 of which coming from an INAF-Large Binocular Telescope (LBT) Strategic Program. We use the spectroscopic redshifts to determine the quality of the photometric ones, and find it in agreement with that of other X-ray surveys which used a similar number of photometric data-points. In particular, we measure a sample normalized median absolute deviation $\sigma_{NMAD}$=1.48||$z_{phot}$-$z_{spec}$||/(1+$z_{spec}$)=0.065. We use these new spectroscopic and photometric redshifts to study the properties of the Chandra J1030 field. We observe several peaks in our spectroscopic redshift distribution between $z$=0.15 and $z$=1.5, and find that the sources in each peak are often distributed across the whole Chandra field of view. This evidence confirms that X-ray selected AGN can efficiently track large-scale structures over physical scales of several Mpc. Finally, we computed the Chandra J1030 $z>$3 number counts: while the spectroscopic completeness at high-redshift of our sample is limited, our results point towards a potential source excess at $z\geq$4, which we plan to either confirm or reject in the near future with dedicated spectroscopic campaigns., Comment: 21 pages, 15 figures. Accepted for publication in Astronomy and Astrophysics

We present results from the KMOS Lens-Amplified Spectroscopic Survey (KLASS), an ESO Very Large Telescope (VLT) large program using gravitational lensing to study the spatially resolved kinematics of 44 star-forming galaxies at 0.61), we find a weak increase or flat trend. We investigate the relation between the rest-frame UV clumpiness of galaxies and their global kinematic properties. We find no clear trend between the clumpiness and the velocity dispersion and $\upsilon_{rot}/\sigma_0$. This could suggest that the kinematic properties of galaxies evolve after the clumps formed in the galaxy disk or that the clumps can form in different physical conditions., Comment: 19 pages, 9 figures. Accepted for publication in MNRAS

International audience; Structural changes in the Zr55Cu30Ni5Al10 liquid alloy on cooling from above the equilibrium liquidus temperature are studied by synchrotron radiation X-ray diffraction and compared with the results of first-principles molecular dynamics simulation. In-situ vitrification of the studied alloy is achieved using a containerless levitation technique. Subsequent analysis of the atomic and electronic structure of the alloy in liquid and glassy states reveals formation of medium-range order on cooling and its relationship with liquid fragility. The structural changes in this alloy are smaller in comparison with a more fragile one.

To extend the search for quasars in the epoch of reionization beyond the tip of the luminosity function, we explore point source candidates at redshift $z\sim8$ in SuperBoRG, a compilation of $\sim$0.4deg$^2$ archival medium-deep ($m_{\rm F160W}\sim 26.5$ABmag, 5$\sigma$) parallel IR images taken with the Hubble Space Telescope (HST). Initial candidates are selected by using the Lyman-break technique. We then carefully analyze source morphology, and robustly identify 3 point sources at $z\sim8$. Photometric redshift analysis reveals that they are preferentially fit by extra-galactic templates, and we conclude that they are unlikely to be low-$z$ interlopers, including brown dwarfs. A clear IRAC ch2 flux excess is seen in one of the point sources, which is expected if the source has strong H$\beta$+[O III] emission with rest-frame equivalent width of $\sim3000$AA. Deep spectroscopic data taken with Keck/MOSFIRE, however, do not reveal Ly$\alpha$ emission from the object. In combination with the estimated H$\beta$+[O III] equivalent width, we place an upper limit on its Ly$\alpha$ escape fraction $f_{\rm esc, Ly\alpha}< 2 \%$. We estimate the number density of these point sources $\sim1\times10^{-6}$Mpc$^{-3}$mag$^{-1}$ at $M_{\rm UV}\sim-23$mag. The final interpretation of our results remains inconclusive: extrapolation from low-$z$ studies of $faint$ quasars suggests that $>100\times$ survey volume may be required to find one of this luminosity. The James Webb Space Telescope will be able to conclusively determine the nature of our luminous point source candidates, while the Roman Space Telescope will probe $\sim 200$ times the area of the sky with the same observing time considered in this HST study., Comment: Accepted for publication in ApJ. 11 pages, 7 figures, 4 tables

A critical component of our understanding of the evolution of Earth's mantle comes from rocks identified as direct mantle samples. Eoarchaean dunite lenses from the Isua Supracrustal Belt (ISB), North Atlantic Craton, Greenland, have been previously interpreted as depleted mantle wedge residues, complementary to arc-like volcanic rocks in the supracrustal sequence. This would place the ISB dunites among Earth's oldest mantle samples. We present new major element, platinum-group element (PGE) and Re-Os isotopic data for the ISB dunites, and critically assess the criteria previously used to invoke a mantle origin for the dunites. We find no evidence that uniquely supports a mantle origin. Instead, evidence of chromite and Os-Ir alloy fractionation, consistent Pt and Pd depletion, elevated Ni contents, and trace element systematics indicate that the dunites formed as olivine ± chromite cumulates with varying amounts of intercumulus melt. Their compositions indicate crystallisation from magmas represented by ISB volcanic rocks, and their Re-Os model ages overlap the ∼3720 Ma age of the volcanic sequence, consistent with the dunites representing magma chambers or conduits that fed the volcanic eruptions. Formation of the Isua dunites as cumulates removes an important line of evidence used to interpret the ISB as an ophiolite, and highlights the risks of using criteria that do not discriminate mantle residues from olivine-rich cumulates. Extending this reasoning to other Eoarchaean crustal peridotites previously identified as mantle rocks suggests there may be no mantle residues anywhere in the Itsaq Gneiss Complex, and that the oldest mantle samples may only be found as xenoliths in volcanic rocks.

We constrain the distribution of spatially offset Lyman-alpha emission (Ly$\alpha$) relative to rest-frame ultraviolet emission in $\sim300$ high redshift ($36$. Spatially resolved observations of Ly$\alpha$ and UV continuum at $6, Comment: Submitted to MNRAS

International audience; 809 deep IODP Hole U1473A at Atlantis Bank, SWIR, is 2.2 km from 1,508-m Hole 735B and 1.4 from 158-m Hole 1105A. With mapping, it provides the first 3-D view of the upper levels of a 660-km 2 lower crustal batholith. It is laterally and vertically zoned, representing a complex interplay of cyclic intrusion, and ongoing deformation, with kilometer-scale upward and lateral migration of interstial melt. Transform wall dives over the gabbro-peridotite contact found only evolved gabbro intruded directly into the mantle near the transform. There was no high-level melt lens, rather the gabbros crystallized at depth, and then emplaced into the zone of diking by diapiric rise of a crystal mush followed by crystal-plastic deformation and faulting. The residues to mass balance the crust to a parent melt composition lie at depth below the center of the massif-likely near the crust-mantle boundary. Thus, basalts erupted to the seafloor from >1,550 mbsf. By contrast, the Mid-Atlantic Ridge lower crust drilled at 23°N and at Atlantis Massif experienced little high-temperature deformation and limited late-stage melt transport. They contain primitive cumulates and represent direct intrusion, storage, and crystallization of parental MORB in thinner crust below the dike-gabbro transition. The strong asymmetric spreading of the SWIR to the south was due to fault capture, with the northern rift valley wall faults cutoff by a detachment fault that extended across most of the zone of intrusion. This caused rapid migration of the plate boundary to the north, while the large majority of the lower crust to spread south unroofing Atlantis Bank and uplifting it into the rift mountains.

Synopsis We present a theoretical study for coherent control based on resonant excitation to doubly excited states of helium. Bichromatic schemes are designed, using XUV light from the seeded free-electron laser FERMI, where the phase of the third harmonic relative to the fundamental can be controlled. In addition to demonstrate the interference effects, we provide detailed theoretical analyses to identify the FEL parameters, such as intensities and pulse durations, needed for experimentally observable coherent control of the photoionization yields.

Local massive early-type galaxies are believed to have completed most of their star formation $\sim10$Gyr ago and evolved without having substantial star formation since. If so, their progenitors should have roughly solar stellar metallicities ($Z_*$), comparable to their values today. We report the discovery of two lensed massive ($\log M_*/M_\odot\sim11$), $z\sim2.2$ dead galaxies, that appear markedly metal deficient given this scenario. Using 17-band $HST$+$K_{s}$+$Spitzer$ photometry and deep $HST$ grism spectra from the GLASS and SN Refsdal follow-up campaigns covering features near $\lambda_{\rm rest}\sim4000$\AA, we find these systems to be dominated by A-type stars with $\log Z_*/Z_\odot=-0.40\pm0.02$ and $-0.49\pm0.03$ ($30$-$40\%$ solar) under standard assumptions. The second system's lower metallicity is robust to isochrone changes, though this choice can drive the first system's from $\log Z_*/Z_\odot=-0.6$ to 0.1. If these two galaxies are representative of larger samples, this finding suggests that evolutionary paths other than dry minor-merging are required for these massive galaxies. Future analyses with direct metallicity measurements-e.g., by the $James\ Webb\ Space\ Telescope$-will provide critical insight into the nature of such phenomena., Comment: Accepted for publication in Astrophysical Journal Letters; 6 pages, 3 figures, 1 table

Each type of testing machine has its own characteristics, but most of multiaxial fatigue studies have been performed by a push-pull and reversed torsion loading testing machine. This type of testing machine can perform multiaxial fatigue tests under non-proportional loading in which principal directions of stress and strain are changed in a cycle. However, a principal strain ratio range performable in this testing method is −1≤ ϕ ≤−ν, where ϕ and ν are the principal strain ratio and the Poisson's ratio. This study discusses about stress and strain states and multiaxial fatigue testing method. In order to perform fatigue test in −1≤ϕ≤+1 under non-proportional loading, a multiaxial fatigue testing machine of combining the push-pull and reversed torsion loading and cyclic inner and outer pressures is also developed. Then, this paper presents experimental results under several multiaxial loadings carried by the testing machine, too.

International Ocean Discovery Program (IODP) Expedition 360 was the first leg of Phase I of the SloMo (shorthand for “The nature of the lower crust and Moho at slower spreading ridges”) Project, a multiphase drilling program that proposes to drill through the outermost of the global seismic velocity discontinuities, the Mohorovicic seismic discontinuity (Moho). The Moho corresponds to a compressional wave velocity increase, typically at ~7 km beneath the oceans, and has generally been regarded as the boundary between crust and mantle. An alternative model, that the Moho is a hydration front in the mantle, has recently gained credence upon the discovery of abundant partially serpentinized peridotite on the seafloor and on the walls of fracture zones, such as at Atlantis Bank, an 11–13 My old elevated oceanic core complex massif adjacent to the Atlantis II Transform on the Southwest Indian Ridge. Hole U1473A was drilled on the summit of Atlantis Bank during Expedition 360, 1–2 km away from two previous Ocean Drilling Program (ODP) holes: Hole 735B (drilled during ODP Leg 118 in 1987 and ODP Leg 176 in 1997) and Hole 1105A (drilled during ODP Leg 179 in 1998). A mantle peridotite/gabbro contact has been traced by dredging and diving along the transform wall for 40 km. The contact is located at ~4200 m depth on the transform wall below the drill sites but shoals considerably 20 km to the south, where it was observed in outcrop at 2563 m depth. Moho reflections, however, have been found at ~5–6 km beneath Atlantis Bank and

This chapter documents the procedures and methods employed in the various shipboard laboratories of the R/V JOIDES Resolution during International Ocean Discovery Program (IODP) Expedition 360. This information applies only to shipboard work described in the Expedition Reports section of the Expedition 360 Proceedings volume, which used the shipboard sample registry, imaging and analytical instruments, core description tools, and the Laboratory Information Management System (LIMS) database. Methods for shore-based analysis of Expedition 360 samples and data will be described in the individual peer-reviewed scientific contributions to be published in the Research Results section of the Expedition 360 Proceedings volume and in international scientific journals and books.