Latest in astro-ph.im

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Remote sensing of geomagnetic fields and atomic collisions in the mesosphereFeb 09 2018Magnetic-field sensing has contributed to the formulation of the plate-tectonics theory, the discovery and mapping of underground structures on Earth, and the study of magnetism in other planets. Filling the gap between space-based and near-Earth observation, ... More
Dispersion of velocity gradients: Mapping magnetization with the Velocity Gradient TechniqueFeb 08 2018Recent developments of the Velocity Gradient Technique (VGT) show that the velocity provides a robust measure of magnetic field direction. In this paper, we use velocity centroids as the measures of velocity and propose a new way of studying media magnetization. ... More
Towards the First Catalog of Fermi-LAT sources below 100 MeVFeb 08 2018Previous analyses of point sources in the gamma-ray range were done either below 30 MeV or above 100 MeV. Below 30 MeV, the imaging Compton telescope (COMPTEL) onboard NASA's Compton Gamma-Ray Observatory detected 26 steady sources in the energy range ... More
A simple method to determine the time delays in presence of microlensing: application to HE 0435-1223 and PG1115+080Feb 07 2018A method for determining the time delays in gravitationally lensed quasars is proposed, which offers a simple and transparent procedure to mitigate the effects of microlensing. The method is based on fundamental properties of representation of quadratically ... More
Fast estimation of orbital parameters in Milky-Way-like potentialsFeb 07 2018Orbital parameters, such as the eccentricity and maximum vertical excursion, of stars in the Milky Way are an important tool for understanding its dynamics and evolution, but the calculation of such parameters usually relies on computationally-expensive ... More
New variable Stars from the Photographic Archive: Semi-automated Discoveries, Attempts of Automatic Classification, and the New Field 104 HerFeb 07 2018Using 172 plates taken with the 40-cm astrograph of the Sternberg Astronomical Institute (Lomonosov Moscow University) in 1976-1994 and digitized with the resolution of 2400 dpi, we discovered and studied 275 new variable stars. We present the list of ... More
EMC design for the actuators of FAST reflectorFeb 07 2018The active reflector is one of the three main innovations of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The deformation of such a huge spherically shaped reflector into different transient parabolic shapes is achieved by using 2225 ... More
Interstellar communication. IX. Message decontamination is impossibleFeb 06 2018A complex message from space may require the use of computers to display, analyze and understand. Such a message cannot be decontaminated with certainty, and technical risks remain which can pose an existential threat. Complex messages would need to be ... More
Analytic Reflected Lightcurves for ExoplanetsFeb 06 2018The disk-integrated reflected brightness of an exoplanet changes as a function of time due to orbital and rotational motion coupled with an inhomogeneous albedo map. We have previously derived analytic reflected lightcurves for spherical harmonic albedo ... More
Astrophysicists and physicists as creators of ArXiv-based commenting resources for their research communities. An initial surveyFeb 06 2018This paper conveys the outcomes of what results to be the first, though initial, overview of commenting platforms and related 2.0 resources born within and for the astrophysical community (from 2004 to 2016). Experiences were added, mainly in the physics ... More
Denoising, Deconvolving and Decomposing multi-Dimensional Photon Observations- The D4PO AlgorithmFeb 06 2018Astronomical imaging based on photon count data is a highly non-trivial task. In this context we show how to denoise, deconvolve, and decompose multidimensional photon observations. The primary objective is to incorporate accurate and well motivated likelihood ... More
BoGEMMS: the Bologna Geant4 multi-mission simulatorFeb 06 2018BoGEMMS, (Bologna Geant4 Multi-Mission Simulator) is a software project for fast simulation of payload on board of scientific satellites for prompt background evaluation that has been developed at the INAF/IASF Bologna. By exploiting the Geant4 set of ... More
Monte Carlo simulations of Gamma-ray space telescopes: a BoGEMMS multi-purpose applicationFeb 06 2018After the development of a BoGEMMS (Bologna Geant4 Multi-Mission Simulator) template for the back- ground study of X-ray telescopes, a new extension is built for the simulation of a Gamma-ray space mission (e.g. AGILE, Fermi), conceived to work as a common, ... More
Calibration of EFOSC2 broadband linear imaging polarimetryFeb 06 2018EFOSC2 (the European Southern Observatory Faint Object Spectrograph and Camera v2) is one of the workhorse instruments on ESO's New Technology Telescope (NTT), and is one of the most popular instruments at La Silla observatory. It is mounted at a Nasmyth ... More
Large Synoptic Survey Telescope Solar System Science RoadmapFeb 06 2018The Large Synoptic Survey Telescope (LSST) is uniquely equipped to search for Solar System bodies due to its unprecedented combination of depth and wide field coverage. Over a ten-year period starting in 2022, LSST will generate the largest catalog of ... More
Solar Imaging using Low Frequency ArraysFeb 06 2018Low frequency imaging radio arrays such as MWA, LWA and LOFAR have been recently commissioned, and significantly more advanced and flexible arrays are planned for the near term. These powerful instruments offer new opportunities for direct solar imaging ... More
Wavefront Sensing in Space: Flight Demonstration II of the PICTURE Sounding Rocket PayloadFeb 05 2018A NASA sounding rocket for high-contrast imaging with a visible nulling coronagraph, the PICTURE payload, has made two suborbital attempts to observe the warm dust disk inferred around Epsilon Eridani. The first flight in 2011 demonstrated a 5 milliarcsecond ... More
On-Orbit Performance of the Helioseismic and Magnetic Imager Instrument onboard the Solar Dynamics ObservatoryFeb 05 2018The Helioseismic and Magnetic Imager (HMI) instrument is a major component of NASA's Solar Dynamics Observatory (SDO) spacecraft. Since beginning normal science operations on 1 May 2010, HMI has operated with remarkable continuity, e.g. during the more ... More
On the PDS of GRB light curvesFeb 05 2018In spite of the complicated behavior in the time domain, long GRBs show a simpler behavior in the Fourier domain of frequencies, represented by power density spectra, PDS. Recently, there are some relations found between GRBs properties and PDS parameters, ... More
Gravitational Waves optical follow-up at VSTFeb 05 2018We report on the deep optical follow-up surveys of the first two gravitational-wave events, GW150914 and GW151226, accomplished by the GRAvitational Wave Inaf TeAm Collaboration (GRAWITA) using the VLT Survey Telescope (VST). We responded promptly to ... More
GRB follow-up and science with THESEUS/IRTFeb 05 2018The aim of the space mission concept \theseus~is to continue to collect and study the GRB events like \swift. It will allow us to study the early Universe. Moreover, it will offer us to study with unprecedented sensitivity GRB emission and to measure ... More
Infrared emission from gravitational wave sources with THESEUS/IRTFeb 05 2018With the discovery of the electromagnetic counterpart of the gravitational wave source GW170817 the multi-messenger era is started. The identification of an electromagnetic counterpart is crucial to understand the nature of the detected gravitational ... More
Synergies between the Cherenkov Telescope Array and THESEUSFeb 05 2018The Cherenkov Telescope Array (CTA) is designed to be the next major observatory operating in the Very High Energy (VHE, $\gtrsim 100$ GeV) gamma-ray band. It will build on the imaging atmospheric Cherenkov technique but will go much further in terms ... More
GPU-accelerated broadband analysis of multi-messenger GRB light curvesFeb 05 2018High-frequency multi-messenger observations provide a powerful probe of gamma-ray bursts (GRBs), pioneered by {\em BeppoSAX} in gamma-rays and LIGO-Virgo in gravitational waves. Identifying the central engines - magnetars or black holes - also promises ... More
GRB Cosmography with THESEUSFeb 05 2018Gamma-ray Bursts can be used as distance indicators using the Combo relation. We show how the proposed THESEUS mission will allow us to investigate the evolution history of the Universe at high redshift with GRBs. Assuming that THESEUS will measure the ... More
The SVOM mission, a pathfinder for THESEUSFeb 05 2018The Sino-French space mission SVOM (Space-based multi-band astronomical Variable Objects Monitor) is mainly designed to detect and localize Gamma-Ray Burst events (GRBs). The satellite, to be launched late 2021, embarks a set of gamma-ray, X-ray and optical ... More
First Stars, Reionization and Gamma-Ray BurstsFeb 05 2018Gamma-Ray Bursts represent unique tools to study the early phases of cosmic evolution, the formation of the first stars and galaxies. Absorption line spectra of these sources located in the Epoch of Reionization might provide us with key information about ... More
THESEUS and the high redshift universeFeb 05 2018Long-duration gamma-ray bursts (long-GRBs) can be detected throughout cosmic history and provide several unique insights into star-formation and galaxy evolution back to the era of reionization. They can be used to map star formation, identify galaxies ... More
THESEUS in the era of Multi-Messenger AstronomyFeb 05 2018The recent discovery of the electromagnetic counterpart of the gravitational wave source GW170817 has demonstrated the huge informative power of multi-messenger observations. Late '20s and early '30s will be a mature era for multi-messenger astronomy. ... More
The Infra-Red Telescope on board the THESEUS missionFeb 05 2018The Infra-Red Telescope (IRT) on board the Transient High Energy Sky and Early Universe Surveyor (THESEUS) ESA M5 candidate mission will play a key role in identifying and characterizing moderate to high redshift Gamma-Ray Bursts afterglows. The IRT is ... More
The Soft X-ray Imager (SXI) on-board the THESEUS missionFeb 05 2018We summarize in this contribution the capabilities, design status, and the en- abling technologies of the Soft X-ray Imager (SXI) planned to be on-board the THESEUS mission. We describe its central role in making THESEUS a powerful machine to probe the ... More
The X-Gamma Imaging Spectrometer (XGIS) onboard THESEUSFeb 05 2018A compact and modular X and gamma-ray imaging spectrometer (XGIS) has been designed as one of the instruments foreseen on-board the THESEUS mission proposed in response to the ESA M5 call. The experiment envisages the use of CsI scintillator bars read ... More
Modal Noise Mitigation through Fiber Agitation for Fiber-fed Radial Velocity SpectrographsFeb 05 2018Optical fiber modal noise is a limiting factor for high precision spectroscopy signal-to-noise in the near-infrared and visible. Unabated, especially when using highly coherent light sources for wavelength calibration, modal noise can induce radial velocity ... More
ATLAS Probe: Breakthrough Science of Galaxy Evolution, Cosmology, Milky Way, and the Solar SystemFeb 05 2018ATLAS (Astrophysics Telescope for Large Area Spectroscopy) Probe is a concept for a NASA probe-class space mission, the spectroscopic follow-up to WFIRST, multiplexing its scientific return by obtaining deep 1 to 4 micron slit spectroscopy for ~90% of ... More
The S-PASS view of polarized Galactic Synchrotron at 2.3 GHz as a contaminant to CMB observationsFeb 04 2018We analyze the Southern Sky emission in linear polarization at 2.3 GHz as observed by the S-band Polarization All Sky Survey S-PASS. Our purpose is to study the properties of the diffuse Galactic polarized synchrotron as a contaminant to CMB B-mode observations. ... More
Numerical verification of the microscopic time reversibility of Newton's equations of motion: Fighting exponential divergenceFeb 03 2018Numerical solutions to Newton's equations of motion for chaotic self gravitating systems of more than 2 bodies are often regarded to be irreversible. This is due to the exponential growth of errors introduced by the integration scheme and the numerical ... More
ProFound: Source Extraction and Application to Modern Survey DataFeb 03 2018We introduce ProFound, a source finding and image analysis package. ProFound provides methods to detect sources in noisy images, generate segmentation maps identifying the pixels belonging to each source, and measure statistics like flux, size and ellipticity. ... More
ATLAS: A High-Cadence All-Sky Survey SystemFeb 02 2018Technology has advanced to the point that it is possible to image the entire sky every night and process the data in real time. The sky is hardly static: many interesting phenomena occur, including variable stationary objects such as stars or QSOs, transient ... More
Development of a Lunar Scintillometer as part of the National Large Optical Telescope Site SurveyFeb 01 2018Ground layer turbulence is a very important site characterization parameter used to assess the quality of an astronomical site. The Lunar Scintillometer is a simple and effective site-testing device for measuring the ground layer turbulence. It consists ... More
The zenithal 4-m International Liquid Mirror Telescope: a unique facility for supernova studiesFeb 01 2018The 4-m International Liquid Mirror Telescope (ILMT) will soon become operational at the newly developed Devasthal observatory near Nainital (Uttarakhand, India). Coupled with a 4k $\times$ 4k pixels CCD detector and TDI optical corrector, it will reach ... More
Methods for multiple telescope beam imaging and guiding in the near infraredJan 31 2018Atmospheric turbulence and precise measurement of the astrometric baseline vector between any two telescopes are two major challenges in implementing phase referenced interferometric astrometry and imaging. They limit the performance of a fibre-fed interferometer ... More
Modelling the Performance of Single-Photon Counting Kinetic Inductance DetectorsJan 31 2018Using conventional superconductor theory we discuss and validate a model that describes the energy-resolving performance of an aluminium LEKID to single-photon absorption events. While aluminium is not the optimum material for single-photon counting applications, ... More
A blind search for a common signal in gravitational wave detectorsJan 31 2018We propose a blind, template-free method for the extraction of a common signal between the Hanford and Livingston detectors and apply it especially to the GW150914 event. We construct a log-likelihood method that maximizes the cross-correlation between ... More
Wide-field Ultraviolet Imager for Astronomical Transient StudiesJan 31 2018Though the ultraviolet (UV) domain plays a vital role in the studies of astronomical transient events, the UV time-domain sky remains largely unexplored. We have designed a wide-field UV imager that can be flown on a range of available platforms, such ... More
A Gaussian Mixture Model for Nulling PulsarsJan 29 2018The phenomenon of pulsar nulling -- where pulsars occasionally turn off for one or more pulses -- provides insight into pulsar-emission mechanisms and the processes by which pulsars turn off when they cross the "death line." However, while ever more pulsars ... More
In-flight measurement of Planck telescope emissivityJan 29 2018The Planck satellite in orbit mission ended in October 2013. Between the end of Low Frequency Instrument (LFI) routine mission operations and the satellite decommissioning, a dedicated test was also performed to measure the Planck telescope emissivity. ... More
Identification of multiple hard X-ray sources in solar flares: A Bayesian analysis of the February 20 2002 eventJan 27 2018Hard X-ray emission in solar flares is typically characterized by a number of discrete sources, each with its own spectral, temporal, and spatial variability. Establishing the relationship amongst these sources is critical to determine the role of each ... More
AAS WorldWide Telescope: Seamless, Cross-Platform Data Visualization Engine for Astronomy Research, Education, and Democratizing DataJan 27 2018The American Astronomical Society's WorldWide Telescope (WWT) project enables terabytes of astronomical images, data, and stories to be viewed and shared among researchers, exhibited in science museums, projected into full-dome immersive planetariums ... More
Polarized Beam Patterns from a Multi-Moded Feed For Observations of the Cosmic Microwave BackgroundJan 26 2018We measure linearly polarized beam patterns for a multi-moded concentrator and compare the results to a simple model based on geometric optics. We convolve the measured co-polar and cross-polar beams with simulated maps of CMB polarization to estimate ... More
Antarctic Surface Reflectivity Calculations and Measurements from the ANITA-4 and HiCal-2 ExperimentsJan 26 2018The balloon-borne HiCal radio-frequency (RF) transmitter, in concert with the ANITA radio-frequency receiver array, is designed to measure the Antarctic surface reflectivity in the RF wavelength regime. The amplitude of surface-reflected transmissions ... More
Perspectives on Reproducibility and Sustainability of Open-Source Scientific Software from Seven Years of the Dedalus ProjectJan 24 2018As the Science Mission Directorate contemplates establishing an open code policy, we consider it timely to share our experiences as the developers of the open-source partial differential equation solver Dedalus. Dedalus is a flexible framework for solving ... More
Initial investigation into the susceptibility of antenna-coupled LEKIDs to two level system affectsJan 24 2018Optical coupling to a lumped-element kinetic inductance detector (LEKID) via an antenna and transmission line structure enables a compact detector architecture, easily optimised for the required sensitivity and multiplexing performance of future cosmic ... More
Machine learning in APOGEE: Unsupervised spectral classification with $K$-meansJan 24 2018Feb 08 2018The data volume generated by astronomical surveys is growing rapidly. Traditional analysis techniques in spectroscopy either demand intensive human interaction or are computationally expensive. In this scenario, machine learning, and unsupervised clustering ... More
SkyMapper Southern Survey: First Data Release (DR1)Jan 24 2018We present the first data release (DR1) of the SkyMapper Southern Survey, a hemispheric survey carried out with the SkyMapper Telescope at Siding Spring Observatory in Australia. Here, we present the survey strategy, data processing, catalogue construction ... More
Technology Needs for Detecting Life Beyond the Solar System: A White Paper in Support of the Astrobiology Science StrategyJan 23 2018Jan 31 2018In support of the Astrobiology Science Strategy, this whitepaper outlines some key technology challenges pertaining to the remote search for life in exoplanetary systems. Finding evidence for life on rocky planets outside of our solar system requires ... More
The EUCLID VIS read-out shutter unit: a low disturbance mechanism at cryogenic temperatureJan 23 2018Euclid is the second medium-size mission (M2) of the ESA Cosmic Vision Program, currently scheduled for a launch in 2020. The two instruments on-board Euclid, VIS (VISible imager) and NISP (Near Infrared Spectrometer and Photometer), will provide key ... More
Towards an automatic wind speed and direction profiler for Wide Field AO systemsJan 23 2018Wide Field Adaptive Optics (WFAO) systems are among the most sophisticated AO systems available today on large telescopes. The knowledge of the vertical spatio-temporal distribution of the wind speed (WS) and direction (WD) are fundamental to optimize ... More
A Continuous 100-mK Helium-Light Cooling System for MUSCAT on the LMTJan 23 2018The MUSCAT instrument is a large-format camera planned for installation on the Large Millimeter Telescope (LMT) in 2018. MUSCAT requires continuous cooling of several large-volume stages to sub-Kelvin temperatures, with the focal plane cooled to 100 mK. ... More
Machine Learning-based Brokers for Real-time Classification of the LSST Alert StreamJan 22 2018The unprecedented volume and rate of transient events that will be discovered by the Large Synoptic Survey Telescope (LSST) demands that the astronomical community update its followup paradigm. Alert-brokers -- automated software system to sift through, ... More
ChromaStarPy: A stellar atmosphere and spectrum modeling and visualization lab in pythonJan 22 2018We announce ChromaStarPy, an integrated general stellar atmospheric modeling and spectrum synthesis code written entirely in python V. 3. ChromaStarPy is a direct port of the ChromaStarServer (CSServ) Java modeling code described in earlier papers in ... More
Identification and mitigation of narrow spectral artifacts that degrade searches for persistent gravitational waves in the first two observing runs of Advanced LIGOJan 22 2018Searches are under way in Advanced LIGO and Virgo data for persistent gravitational waves from continuous sources, e.g. rapidly rotating galactic neutron stars, and stochastic sources, e.g. relic gravitational waves from the Big Bang or superposition ... More
Excitation and charge transfer in low-energy hydrogen atom collisions with neutral ironJan 22 2018Data for inelastic processes due to hydrogen atom collisions with iron are needed for accurate modelling of the iron spectrum in late-type stars. Excitation and charge transfer in low-energy Fe+H collisions is studied theoretically using a previously ... More
The LiteBIRD Satellite Mission - Sub-Kelvin InstrumentJan 22 2018Jan 24 2018Inflation is the leading theory of the first instant of the universe. Inflation, which postulates that the universe underwent a period of rapid expansion an instant after its birth, provides convincing explanation for cosmological observations. Recent ... More
Measurement of low-energy background events due to $^{222}$Rn contamination on the surface of a NaI(Tl) crystalJan 22 2018It has been known that decays of $^{222}$Rn and its daughter elements on the surface of a detector cause significant background at energies below 10~keV. In particular $^{210}$Pb and $^{210}$Po decays on the crystal surface result in significant background ... More
Soft X-ray Imager aboard Hitomi (ASTRO-H)Jan 22 2018Feb 02 2018The Soft X-ray Imager (SXI) is an imaging spectrometer using charge-coupled devices (CCDs) aboard the Hitomi X-ray observatory. The SXI sensor has four CCDs with an imaging area size of $31~{\rm mm} \times 31~{\rm mm}$ arranged in a $2 \times 2$ array. ... More
Peak-locking centroid bias in Shack-Hartmann wavefront sensingJan 21 2018Shack-Hartmann wavefront sensing relies on accurate spot centre measurement. Several algorithms were developed with this aim, mostly focused on precision, i.e. minimizing random errors. In the solar and extended scene community, the importance of the ... More
Precision Projector Laboratory: Detector Characterization with an Astronomical Emulation TestbedJan 19 2018As astronomical observations from space benefit from improved sensitivity, the effectiveness of scientific programs is becoming limited by systematics that often originate in poorly understood image sensor behavior. Traditional, bottom-up detector characterization ... More
Design and performance of the antenna coupled lumped-element kinetic inductance detectorJan 19 2018Focal plane arrays consisting of low-noise, polarisation-sensitive detectors have made possible the pioneering advances in the study of the cosmic microwave background (CMB). To make further progress, the next generation of CMB experiments (e.g. CMB-S4) ... More
Evidence of a non universal stellar Initial Mass Function. Insights from HST optical imaging of 6 Ultra Faint Dwarf Milky Way SatellitesJan 18 2018Using deep HST/ACS observations, we demonstrate that the sub-solar stellar initial mass function (IMF) of 6 ultra-faint dwarf Milky Way Satellites (UFDs) is more bottom light than the IMF of the Milky Way disk. Our data have a lower mass limit of about ... More
Revealing compact structures of interstellar plasma in the Galaxy with RadioAstronJan 18 2018Jan 24 2018The aim of our work was to study the spatial structure of inhomogeneities of interstellar plasma in the directions of five pulsars: B0823+26, B0834+06, B1237+25, B1929+10, and B2016+28. Observations of these pulsars were made with RadioAstron space-ground ... More
The contact binary VW Cephei revisited: surface activity and period variationJan 18 2018Context. Despite the fact that VW Cephei is one of the well-studied contact binaries in the literature, there is no fully consistent model available that can explain every observed property of this system. Aims. Our motivation is to obtain new spectra ... More
Formation of massive seed black holes via collisions and accretionJan 17 2018Models aiming to explain the formation of massive black hole seeds, and in particular the direct collapse scenario, face substantial difficulties. These are rooted in rather ad hoc and fine-tuned initial conditions, such as the simultaneous requirements ... More
Resolving discrete pulsar spin-down states with current and future instrumentationJan 17 2018An understanding of pulsar timing noise offers the potential to improve the timing precision of a large number of pulsars as well as facilitating our understanding of pulsar magnetospheres. For some sources, timing noise is attributable to a pulsar switching ... More
Life Beyond the Solar System: Space Weather and Its Impact on Habitable WorldsJan 16 2018The search of life in the Universe is a fundamental problem of astrobiology and a major priority for NASA. A key area of major progress since the NASA Astrobiology Strategy 2015 (NAS15) has been a shift from the exoplanet discovery phase to a phase of ... More
Searching for Exoplanets Using a Microresonator AstrocombJan 16 2018Detection of weak radial velocity shifts of host stars induced by orbiting planets is an important technique for discovering and characterizing planets beyond our solar system. Optical frequency combs enable calibration of stellar radial velocity shifts ... More
FSD: Frequency Space Differential measurement of CMB spectral distortionsJan 16 2018Although the Cosmic Microwave Background agrees with a perfect blackbody spectrum within the current experimental limits, it is expected to exhibit certain spectral distortions with known spectral properties. We propose a new method, Frequency Space Differential ... More
Planck intermediate results. LIV. Polarized dust foregroundsJan 15 2018The study of polarized dust emission has become entwined with the analysis of the cosmic microwave background (CMB) polarization. We use new Planck maps to characterize Galactic dust emission as a foreground to the CMB polarization. We present Planck ... More
Radio Galaxy Zoo: Compact and extended radio source classification with deep learningJan 15 2018Machine learning techniques have been increasingly useful in astronomical applications over the last few years, for example in the morphological classification of galaxies. Convolutional neural networks have proven to be highly effective in classifying ... More
Cobalt: A GPU-based correlator and beamformer for LOFARJan 15 2018For low-frequency radio astronomy, software correlation and beamforming on general purpose hardware is a viable alternative to custom designed hardware. LOFAR, a new-generation radio telescope centered in the Netherlands with international stations in ... More
Inferring Galactic magnetic field model parameters using IMAGINE - An Interstellar MAGnetic field INference EngineJan 12 2018Context. The Galactic magnetic field (GMF) has a huge impact on the evolution of the Milky Way. Yet currently there exists no standard model for it, as its structure is not fully understood. In the past many parametric GMF models of varying complexity ... More
Influence of misalignments on performance of externally occulted solar coronagraphs. Application to PROBA-3/ASPIICSJan 12 2018ASPIICS is a novel externally occulted coronagraph that will be launched onboard the PROBA-3 mission of ESA. The external occulter (EO) will be placed on one satellite ~150 m ahead of the second satellite with an optical instrument. During part of each ... More
A recent history of science cases for interferometryJan 12 2018Optical long-baseline interferometry is a unique and powerful technique for astronomical research. Since 2004, optical interferometers have produced an increasing number of scientific papers covering various fields of astrophysics. As current interferometric ... More
Space-based infrared interferometry to study exoplanetary atmospheresJan 12 2018The quest for other habitable worlds and the search for life among them are major goals of modern astronomy. One way to make progress towards these goals is to obtain high-quality spectra of a large number of exoplanets over a broad range of wavelengths. ... More
The path towards high-contrast imaging with the VLTI: the Hi-5 projectJan 12 2018The development of high-contrast capabilities has long been recognized as one of the top priorities for the VLTI. As of today, the VLTI routinely achieves contrasts of a few 10$^{-3}$ in the near-infrared with PIONIER (H band) and GRAVITY (K band). Nulling ... More
Optical Follow-up of Planck Cluster Candidates with Small InstrumentsJan 12 2018We report on the search for optical counterparts of Planck Sunyaev-Zel'dovich (SZ) cluster candidates using a 0.6 meter non-professional telescope. Among the observed sources, an unconfirmed candidate, PSZ2 G156.24+22.32, is found to be associated with ... More
QUBIC - The Q&U Bolometric Interferometer for Cosmology - A novel way to look at the polarized Cosmic Microwave BackgroundJan 11 2018In this paper we describe QUBIC, an experiment that takes up the challenge posed by the detection of primordial gravitational waves with a novel approach, that combines the sensitivity of state-of-the art bolometric detectors with the systematic effects ... More
Experimental Confirmation of the Magnetorotational Instability MechanismJan 10 2018The Magnetorotational Instability (MRI) has long been considered a plausibly ubiquitous mechanism to destabilize Keplerian flows, transport angular momentum, and facilitate fast accretion in astrophysical objects. But heretofore, experimental validation ... More
Another unWISE Update: The Deepest Ever Full-sky Maps at 3-5 micronsJan 10 2018We have uniformly reprocessed ~140 terabytes of WISE and NEOWISE exposures to create the deepest ever full-sky maps at 3.4 microns (W1) and 4.6 microns (W2). Our coadds include ~4 years of observations and therefore feature ~4 times greater integer frame ... More
The Dark Energy Survey Data Release 1Jan 09 2018We describe the first public data release of the Dark Energy Survey, DES DR1, consisting of reduced single epoch images, coadded images, coadded source catalogs, and associated products and services assembled over the first three years of DES science ... More
The Dark Energy Survey Image Processing PipelineJan 09 2018The Dark Energy Survey (DES) is a five-year optical imaging campaign with the goal of understanding the origin of cosmic acceleration. DES performs a 5000 square degree survey of the southern sky in five optical bands (g,r,i,z,Y) to a depth of ~24th magnitude. ... More
Advanced Environmentally Resistant Lithium Fluoride Mirror Coatings for the Next-Generation of Broadband Space ObservatoriesJan 09 2018Recent advances in the physical vapor deposition (PVD) of protective fluoride films have raised the far-ultraviolet (FUV: 912-1600 {\AA}) reflectivity of aluminum-based mirrors closer to the theoretical limit. The greatest gains, at more than 20%, have ... More
Breakthrough Listen Observations of 1I/'Oumuamua with the GBTJan 09 2018Jan 10 2018We have conducted a search for radio emission consistent with an artificial source targeting 1I/'Oumuamua with the Robert C. Byrd Green Bank Telescope (GBT) between 1.1 and 11.6 GHz. We searched the data for narrowband signals and found none. Given the ... More
The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core packageJan 08 2018Jan 16 2018The Astropy project supports and fosters the development of open-source and openly-developed Python packages that provide commonly-needed functionality to the astronomical community. A key element of the Astropy project is the core package Astropy, which ... More
Realistic Image Degradation with Measured PSFJan 07 2018Training autonomous vehicles requires lots of driving sequences in all situations\cite{zhao2016}. Typically a simulation environment (software-in-the-loop, SiL) accompanies real-world test drives to systematically vary environmental parameters. A missing ... More
Radiation pressure in galactic disks: stability, turbulence, and winds in the single-scattering limitJan 04 2018The radiation force on dust grains may be dynamically important in driving turbulence and outflows in rapidly star-forming galaxies. Recent studies focus on the highly optically-thick limit relevant to the densest ultra-luminous galaxies and super star ... More
Results from the Atacama B-mode Search (ABS) ExperimentJan 04 2018The Atacama B-mode Search (ABS) is an experiment designed to measure cosmic microwave background (CMB) polarization at large angular scales ($\ell>40$). It operated from the ACT site at 5190~m elevation in northern Chile at 145 GHz with a net sensitivity ... More
OGLE-2016-BLG-1045: A Test of Cheap Space-Based Microlens ParallaxesDec 30 2017Microlensing is a powerful and unique technique to probe isolated objects in the Galaxy. To study the characteristics of these interesting objects based on the microlensing method, measurement of the microlens parallax is required to determine the properties ... More
Interstellar communication. VII. Benchmarking inscribed matter probesDec 29 2017We have explored the optimal frequency of interstellar photon communications (arXiv:1711.05761) and benchmarked other particles as information carriers (arXiv:1711.07962) in previous papers of this series. We now compare the latency and bandwidth of sending ... More
Systematic calibration error requirements for gravitational-wave detectors via the Cramér-Rao boundDec 28 2017Gravitational-wave (GW) laser interferometers such as Advanced LIGO transduce spacetime strain into optical power fluctuation. Converting this optical power fluctuations back into an estimated spacetime strain requires a calibration process that accounts ... More
Noise Budget and Interstellar Medium Mitigation Advances in the NANOGrav Pulsar Timing ArrayDec 26 2017Gravitational wave (GW) detection with pulsar timing arrays (PTAs) requires accurate noise characterization. The noise of our Galactic-scale GW detector has been systematically evaluated by the Noise Budget and Interstellar Medium Mitigation working groups ... More