Search results for "Temporal resolution"
showing 10 items of 110 documents
The synergy of water quality and sea surface currents data in determining the spatio-temporal evolution of large-scale circulation features
2014
Chlorophyll-a (CHL-a) and Sea Surface Temperature (SST), amongst others, are proxies or indicators for water quality and can be easily retrieved synoptically and almost in near-real time through satellite remote-sensing. However, as they evolve in space and time in response to winds and currents, a full resolution of the temporal and spatial scales of these latters is required and their influence in shaping the distribution of water quality parameters needs to be assessed. While providing synoptic views and revealing mesoscale features, satellites suffer, indeed, from inadequate representation of sub-grid physical processes and lack of temporal resolution. Conventional point-wise measuremen…
Improved orbital parameters of accreting millisecond pulsar SAX J1808.4-3658
2006
Abstract We analyze the three outbursts of the X-ray millisecond pulsar SAX J1808.4-3658 that occurred in 1998, 2000, and 2002 observed with RXTE. With a technique based on epoch folding search we find an unique orbital solution valid over the five years of high temporal resolution data available. We revise the estimate of the orbital period, P orb = 7249.1569(1) s and of its error, which we decrease by one order of magnitude. We also give the first constraint on the orbital period derivative, - 6.6 × 10 - 12 P ˙ orb + 0.8 × 10 - 12 s s - 1 . We find that in 2002 the pulse profile shape is clearly asymmetric, showing a secondary peak at about 145° from the main pulse, which is different fr…
Skin-remitted photon path lengths: experimental study
2020
Skin-remitted picosecond laser pulses were detected at four input-output fiber distances in the spectral range 560-800 nm. After deconvolution procedures, distributions and mean values of the remitted photon path lengths in forearm skin were analyzed.
Statistics of reversible bond dynamics observed in force-clamp spectroscopy
2010
We present a detailed analysis of two-state trajectories obtained from force-clamp spectroscopy (FCS) of reversibly bonded systems. FCS offers the unique possibility to vary the equilibrium constant in two-state kinetics, for instance the unfolding and refolding of biomolecules, over many orders of magnitude due to the force dependency of the respective rates. We discuss two different kinds of counting statistics, the event-counting usually employed in the statistical analysis of two-state kinetics and additionally the so-called cycle-counting. While in the former case all transitions are counted, cycle-counting means that we focus on one type of transitions. This might be advantageous in p…
ESTIMATING SMALL ANGULAR SCALE COSMIC MICROWAVE BACKGROUND ANISOTROPY WITH HIGH-RESOLUTIONN-BODY SIMULATIONS: WEAK LENSING
2010
We estimate the impact of weak lensing by strongly nonlinear cosmological structures on the cosmic microwave background. Accurate calculation of large l multipoles requires N-body simulations and ray-tracing schemes with both high spatial and temporal resolution. To this end, we have developed a new code that combines a gravitational Adaptive Particle-Particle, Particle-Mesh solver with a weak-lensing evaluation routine. The lensing deviations are evaluated while structure evolves during the simulation so that all evolution steps—rather than just a few outputs—are used in the lensing computations. The new code also includes a ray-tracing procedure that avoids periodicity effects in a univer…
Strong Exciton-Coherent Phonon Coupling in Single-Layer MoS2
2020
Broadband transient absorption with sub-20fs temporal resolution, supported by ab-initio calculations, quantitatively provides the strength of exciton-coherent phonon coupling in 1L-MoS2, showing a resonant profile around the C exciton.
HINODE /EIS SPECTROSCOPIC VALIDATION OF VERY HOT PLASMA IMAGED WITH THE SOLAR DYNAMICS OBSERVATORY IN NON-FLARING ACTIVE REGION CORES
2012
We use coronal imaging observations with SDO/AIA, and Hinode/EIS spectral data, to explore the potential of narrow band EUV imaging data for diagnosing the presence of hot (T >~5MK) coronal plasma in active regions. We analyze observations of two active regions (AR 11281, AR 11289) with simultaneous AIA imaging, and EIS spectral data, including the CaXVII line (at 192.8A) which is one of the few lines in the EIS spectral bands sensitive to hot coronal plasma even outside flares. After careful coalignment of the imaging and spectral data, we compare the morphology in a 3 color image combining the 171, 335, and 94A AIA spectral bands, with the image obtained for CaXVII emission from the an…
GrailQuest: hunting for atoms of space and time hidden in the wrinkle of Space-Time: A swarm of nano/micro/small-satellites to probe the ultimate str…
2021
AbstractGrailQuest(Gamma Ray Astronomy International Laboratory for QUantum Exploration of Space-Time) is a mission concept based on a constellation (hundreds/thousands) of nano/micro/small-satellites in low (or near) Earth orbits. Each satellite hosts a non-collimated array of scintillator crystals coupled with Silicon Drift Detectors with broad energy band coverage (keV-MeV range) and excellent temporal resolution (≤ 100 nanoseconds) each with effective area$\sim 100 \text {cm}^{2}$∼100cm2. This simple and robust design allows for mass-production of the satellites of the fleet. This revolutionary approach implies a huge reduction of costs, flexibility in the segmented launching strategy, …
2017
Accretion dynamics in the formation of young stars is still a matter of debate because of limitations in observations and modeling. Through scaled laboratory experiments of collimated plasma accretion onto a solid in the presence of a magnetic field, we open a first window on this phenomenon by tracking, with spatial and temporal resolution, the dynamics of the system and simultaneously measuring multiband emissions. We observe in these experiments that matter, upon impact, is ejected laterally from the solid surface and then refocused by the magnetic field toward the incoming stream. This ejected matter forms a plasma shell that envelops the shocked core, reducing escaped x-ray emission. T…
Dissipative rogue wave generation from a mode-locked fiber laser experiment
2012
Rare events of extremely high optical intensity are experimentally recorded at the output of a mode-locked fiber laser operating in a chaotic multiple-pulse regime. These fluctuations result from ceaseless nonlinear interactions between pulses.