Latest in astro-ph.im

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Spatially resolved spectroscopy of the debris disk HD 32297: Further evidence of small dust grainsAug 22 2019Spectro-photometry of debris disks in total intensity and polarimetry can provide new insight into the properties of the dust grains therein (size distribution and optical properties). We aim to constrain the morphology of the highly inclined debris disk ... More
Characterization of Two PMT Models for the IceCube Upgrade mDOMAug 22 2019The IceCube Upgrade will expand the IceCube Neutrino Observatory with nearly 800 new optical modules. A large fraction of these will be multi-PMT optical modules (mDOMs), featuring 24 PMTs pointing uniformly in all directions, providing an almost homogeneous ... More
Into the Darkness: Classical and Type II Cepheids in the Zona Galactica IncognitaAug 22 2019The far side of the Milky Way's disk is one of the most concealed parts of the known Universe due to extremely high interstellar extinction and point source density toward low Galactic latitudes. Large time-domain photometric surveys operating in the ... More
Contour Detection in Cassini ISS images based on Hierarchical Extreme Learning Machine and Dense Conditional Random FieldAug 22 2019In Cassini ISS (Imaging Science Subsystem) images, contour detection is often performed on disk-resolved object to accurately locate their center. Thus, the contour detection is a key problem. Traditional edge detection methods, such as Canny and Roberts, ... More
Revisiting the expected Micro-X signal from the 3.5 keV lineAug 22 2019One of the future instruments to resolve the origin of the unidentified 3.5 keV emission line is the Micro-X sounding rocket telescope. According to the estimate made in 2015, Micro-X will be able to detect on average about 18.2 photons from the 3.5 keV ... More
Modeling the Gaia Color-Magnitude Diagram with Bayesian Neural Flows to Constrain Distance EstimatesAug 21 2019We demonstrate an algorithm for learning a flexible color-magnitude diagram from noisy parallax and photometry measurements using a normalizing flow, a deep neural network capable of learning an arbitrary multi-dimensional probability distribution. We ... More
An improved muon track reconstruction for IceCubeAug 21 2019IceCube is a cubic-kilometer Cherenkov telescope operating at the South Pole. One of its main objectives is to detect astrophysical neutrinos and identify their sources. High-energy muon neutrinos are identified through the secondary muons produced via ... More
Symmetrizing the signal distribution of radio emission from inclined air showersAug 21 2019Radio detection of inclined air showers currently receives special attention. It can be performed with very sparse antenna arrays and yields a pure measurement of the electromagnetic air-shower component, thus delivering information that is highly complementary ... More
Rotational spectroscopy of methyl mercaptan CH$_3$$^{32}$SH at millimeter and submillimeter wavelengthsAug 21 2019We present a new global study of the millimeter (mm) wave, submillimeter (sub-mm) wave, and terahertz (THz) spectra of the lowest three torsional states of methyl mercaptan (CH$_3$SH). New measurements have been carried out between 50 and 510 GHz using ... More
The camera system for the IceCube UpgradeAug 21 2019The IceCube Neutrino Observatory is a cubic kilometer volume neutrino detector installed in the Antarctic at the geographic South Pole. Neutrinos are detected through the observation of Cherenkov light from charged relativistic particles generated in ... More
The SPICEcore Hole Camera SystemAug 21 2019IceCube is a cubic-kilometer scale neutrino telescope located at the geographic South Pole. The detector utilizes the extremely transparent Antarctic ice as a medium for detecting Cherenkov radiation from neutrino interactions. As a result of extensive ... More
GAUSS -- A Sample Return Mission to CeresAug 21 2019The goal of Project GAUSS is to return samples from the dwarf planet Ceres. Ceres is the most accessible ocean world candidate and the largest reservoir of water in the inner solar system. It shows active cryovolcanism and hydrothermal activities in recent ... More
Recent Advances in Frequency-Multiplexed TES Readout: Vastly Reduced Parasitics and an Increase in Multiplexing Factor with sub-Kelvin SQUIDsAug 20 2019Cosmic microwave background (CMB) measurements are fundamentally limited by photon statistics. Therefore, ground-based CMB observatories have been increasing the number of detectors that are simultaneously observing the sky. Thanks to the advent of monolithically ... More
Latest news from the HAWC outrigger arrayAug 20 2019The High Altitude Water Cherenkov (HAWC) observatory is a very high energy gamma-ray detector located in Mexico. In late 2018, the HAWC collaboration completed a major upgrade consisting of the addition of a sparse outrigger array of 345 small water Cherenkov ... More
Light diffusion in birefringent polycrystals and the IceCube ice anisotropyAug 20 2019The IceCube Neutrino Observatory instruments about 1 km^3 of deep, glacial ice at the geographic South Pole with 5160 photomultipliers to detect Cherenkov light from charged relativistic particles. The experiment pursues a wide range of scientific questions ... More
Precise Radial Velocities of Cool Low Mass Stars With iSHELLAug 20 2019The coolest dwarf stars are intrinsically faint at visible wavelengths and exhibit rotationally modulated stellar activity from spots and plages. It is advantageous to observe these stars at near infrared (NIR) wavelengths (1-2.5 microns) where they emit ... More
How to Find Variable Active Galactic Nuclei with Machine LearningAug 20 2019Machine-learning (ML) algorithms will play a crucial role in studying the large datasets delivered by new facilities over the next decade and beyond. Here, we investigate the capabilities and limits of such methods in finding galaxies with brightness-variable ... More
PICO: Probe of Inflation and Cosmic OriginsAug 20 2019The Probe of Inflation and Cosmic Origins (PICO) is a proposed probe-scale space mission consisting of an imaging polarimeter operating in frequency bands between 20 and 800 GHz. We describe the science achievable by PICO, which has sensitivity equivalent ... More
Effects of the atmospheric electric field on the HAWC scaler rateAug 20 2019Strong electric fields in thunderclouds have long been known to accelerate secondary charged particles. We investigate this effect using three years (2015-2017) of data from the scalar system of the High Altitude Water Cherenkov (HAWC) observatory, which ... More
Atmospheric pressure dependance of HAWC scaler systemAug 20 2019The variation in atmospheric pressure is due to changes in mass of the air column above, which in turn resembles the density variation of atmosphere and will affect the decay of secondary particles of cosmic rays. The ground based cosmic ray detectors ... More
New Spatially Resolved Imaging of the SR 21 Transition Disk and Constraints on the Small-Grain Disk GeometryAug 20 2019We present new 0.6 - 4 $\mu$m imaging of the SR 21 transition disk from Keck/NIRC2 and Magellan/MagAO. The protoplanetary disk around SR 21 has a large (~ 30 - 40 AU) clearing first inferred from its spectral energy distribution and later detected in ... More
Numerical Error in Interplanetary Orbit Determination SoftwareAug 20 2019The core of every orbit determination process is the comparison between the measured observables and their predicted values, computed using the adopted mathematical models, and the minimization, in a least square sense, of their differences, known as ... More
Data Quality Monitoring system in the Baikal-GVD experimentAug 20 2019The quality of the incoming experimental data has a significant importance for both analysis and running the experiment. The main point of the Baikal-GVD DQM system is to monitor the status of the detector and obtained data on the run-by-run based analysis. ... More
Enabling a new detection channel for beyond standard model physics with in-situ measurements of ice luminescenceAug 20 2019The IceCube neutrino observatory uses $1\,\mathrm{km}^{3}$ of the natural Antarctic ice near the geographic South Pole as optical detection medium. When charged particles, such as particles produced in neutrino interactions, pass through the ice with ... More
$L_1$ Trend Filtering: A Modern Statistical Tool for Time-Domain Astronomy and Astronomical SpectroscopyAug 20 2019The problem of estimating a one-dimensional signal possessing mixed degrees of smoothness is ubiquitous in time-domain astronomy and astronomical spectroscopy. For example, in the time domain, an astronomical object may exhibit a smoothly varying intensity ... More
Atomic Layer Deposition Niobium Nitride Films for High-Q ResonatorsAug 20 2019Niobium nitride (NbN) is a useful material for fabricating detectors because of its high critical temperature and relatively high kinetic inductance. In particular, NbN can be used to fabricate nanowire detectors and mm-wave transmission lines. When deposited, ... More
The Third Data Release of the Beijing-Arizona Sky SurveyAug 19 2019The Beijing-Arizona Sky Survey (BASS) is a wide and deep imaging survey to cover a 5400 deg$^2$ area in the Northern Galactic Cap with the 2.3m Bok telescope using two filters ($g$ and $r$ bands). The Mosaic $z$-band Legacy Survey (MzLS) covers the same ... More
Upgraded antennas for pulsar observations in the Argentine Institute of Radio astronomyAug 19 2019The Argentine Institute of Radio astronomy (IAR) is equipped with two single-dish 30mts radio antennas capable of performing daily observations of pulsars and radio transients in the southern hemisphere at 1.4 GHz. We aim to introduce to the international ... More
Machine Learning Classifiers for Intermediate Redshift Emission Line GalaxiesAug 19 2019Classification of intermediate redshift ($z$ = 0.3--0.8) emission line galaxies as star-forming galaxies, composite galaxies, active galactic nuclei (AGN), or low-ionization nuclear emission regions (LINERs) using optical spectra alone was impossible ... More
The K2 Bright Star Survey I: Methodology and Data ReleaseAug 19 2019While the Kepler Mission was designed to look at tens of thousands of faint stars (V > 12), brighter stars that saturated the detector are important because they can be and have been observed very accurately by other instruments. By analyzing the unsaturated ... More
Geant4-based electromagnetic background model for the CRESST dark matter experimentAug 19 2019The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) dark matter search experiment aims for the detection of dark matter particles via elastic scattering off nuclei in $\mathrm{CaWO_4}$ crystals. To understand the CRESST electromagnetic ... More
Calibration and operation of SiPM-based cameras for gamma-ray astronomy in presence of high night-sky lightAug 19 2019The next generation of Cherenkov telescope cameras feature Silicon Photo Multipliers (SiPM), which can guarantee excellent performance and allow for observation also under moonlight, increasing duty-cycle and therefore the physics reach. A 4 m-diameter ... More
Quest for detection of a cosmological signal from neutral hydrogen with a digital radio array developed for air-shower measurementsAug 19 2019Digital radio arrays are widely used for the low-frequency radio astronomy as well as for detection of air-showers induced by high-energy cosmic rays and neutrinos. Since the radio emission from air-showers forms short broadband pulses with duration of ... More
NAOMI: the adaptive optics system of the Auxiliary Telescopes of the VLTIAug 19 2019The tip-tilt stabilisation system of the 1.8 m Auxiliary Telescopes of the Very Large Telescope Interferometer was never dimensioned for robust fringe tracking, except when atmospheric seeing conditions are excellent. Increasing the level of wavefront ... More
Air shower reconstruction using HAWC and the Outrigger arrayAug 19 2019The High Altitude Water Cherenkov (HAWC) gamma-ray observatory detects cosmic- and gamma-ray initiated air showers in the TeV energy range using 300 water Cherenkov detectors (WCDs). To improve its sensitivity at the highest energies, HAWC has been upgraded ... More
Experimental Study of a Planar-integrated Dual-Polarization Balanced SIS MixerAug 19 2019A dual-polarization balanced superconductor-insulator-superconductor mixer operating at 2 mm wavelength is realized in form of a monolithic planar integrated circuit. Planar orthomode transducers and LO couplers are enabled by using silicon membranes ... More
VERITAS Observations of Fast Radio BurstsAug 18 2019Fast radio bursts (FRBs) are bright, unresolved, millisecond-duration flashes of radio emission originating from outside of the Milky Way. The source of these mysterious outbursts is unknown, but their high luminosity, high dispersion measure and short ... More
Predictive model of persistence in H2RG detectorsAug 18 2019Infrared hybridized detectors are widely used in astronomy, and their performance can be degraded by image persistence. This results in remnant images that can persist in the detector for many hours, contaminating any subsequent low-background observations. ... More
Modeling subgrid combustion processes in simulations of thermonuclear supernovaeAug 16 2019Supernovae of type Ia are thought to arise from the thermonuclear incineration of a carbon-oxygen white dwarf stellar remnant. However, the detailed explosion scenario and stellar evolutionary origin scenario -- or scenarios -- which lead to observed ... More
On the optimal calibration of VVV photometryAug 16 2019Prompted by some inconsistencies in the photometry of the VISTA Variables in the V\'ia L\'actea (VVV) survey, we conduct a revision of the standard calibration procedure of VISTA data in the $J$, $H$, and $K_S$ passbands. Two independent sources of bias ... More
A Low-Profile, Self-Contained System for Atmospheric Monitoring and Mid-flight Collection of Viable Microbiological Samples at High AltitudeAug 16 2019The prevalence of bacteria in the atmosphere has been well established in relevant literature, suggesting that airborne bacteria can influence atmospheric characteristics including the development of clouds. Studies have also demonstrated that the atmospheric ... More
Astrometric planet search around southern ultracool dwarfs IV. Relative motion of the FORS2/VLT CCD chipsAug 16 2019We present an investigation of the stability of the two chips in the FORS2 camera CCD mosaic on the basis of astrometric observations of stars in 20 sky fields, some of which were monitored for four to seven years. We detected a smooth relative shear ... More
Gaia Parallax of Milky Way Globular Clusters -- A Solution of Mixture ModelAug 16 2019We have established a mixture model approach to derive the parallax of the Milky Way globular clusters. It avoids the problem of cluster membership determination and provides a completely independent astrometrical solution by purely using the parallax ... More
Nulling at short wavelengths: theoretical performance constraints and a demonstration of faint companion detection inside the diffraction limit with a rotating-baseline interferometerAug 16 2019The Palomar Fiber Nuller (PFN) is a rotating-baseline nulling interferometer that enables high-accuracy near-infrared (NIR) nulling observations with full azimuth coverage. To achieve NIR null-depth accuracies of several x 10-4, the PFN uses a common-mode ... More
Modeling of rigidity dependent CORSIKA simulations for GRAPES-3Aug 16 2019The GRAPES-3 muon telescope located in Ooty, India records 4x10^9 muons daily. These muons are produced by interaction of primary cosmic rays (PCRs) in the atmosphere. The high statistics of muons enables GRAPES-3 to make precise measurement of various ... More
Summary of the plenary sessions at European Space Weather Week 15: space weather users and service providers working together now and in the futureAug 16 2019During European Space Weather Week 15 two plenary sessions were held to review the status of operational space weather forecasting. The first session addressed the topic of working with space weather service providers now and in the future, the user perspective. ... More
Design and experimental demonstration of a laser modulation system for future gravitational-wave detectorsAug 16 2019Detuning the signal-recycling cavity length from a cavity resonance significantly improves the quantum noise beyond the standard quantum limit, while there is no km-scale gravitational-wave detector successfully implemented the technique. The detuning ... More
OPTICAM: A triple-camera optical system designed to explore the fastest timescales in AstronomyAug 15 2019We report the development of a high-time resolution, 3-colour, simultaneous optical imaging system for the 2.1 m telescope in San Pedro M\'artir Observatory, M\'exico. OPTICAM will be equipped with three Andor Zyla 4.2-Plus sCMOS cameras and a set of ... More
Detecting Gravitational Waves in Data with Non-Gaussian NoiseAug 15 2019Searches for gravitational waves crucially depend on exact signal processing of noisy strain data from gravitational wave detectors, which are known to exhibit significant non-Gaussian behavior. In this paper, we study two distinct non-Gaussian effects ... More
A Method for an Untriggered, Time-Dependent, Source-Stacking Search for Neutrino FlaresAug 15 2019Recent results from IceCube regarding TXS 0506+056 suggest that it may be useful to test the hypothesis of multiple neutrino flares, where each flare is not necessarily accompanied by a corresponding gamma-ray flare. An untriggered, time-dependent, source-stacking ... More
REBOUNDx: A Library for Adding Conservative and Dissipative Forces to Otherwise Symplectic N-body IntegrationsAug 15 2019Symplectic methods, in particular the Wisdom-Holman map, have revolutionized our ability to model the long-term, conservative dynamics of planetary systems. However, many astrophysically important effects are dissipative. The consequences of incorporating ... More
A positioning system for Baikal-GVDAug 15 2019A cubic kilometer scale neutrino telescope Baikal-GVD is currently under construction in Lake Baikal. Baikal-GVD is designed to detect Cerenkov radiation from products of astrophysical neutrino interactions with Baikal water by a lattice of photodetectors ... More
Development of a UV-transparent Lens Array for Enlarging the Effective Area of Multichannel SiPMsAug 15 2019We developed a UV-transparent lens array that can increase the photon detection efficiency of a silicon photomultiplier (SiPM) array comprising of 64 pixels ($3\times3$ mm$^2$ each) and 0.2-mm gaps. Through the plano-convex spherical lens on each $3.2\times3.2$ ... More
The nature of the diffuse light near cities detected in nighttime satellite imageryAug 15 2019Diffuse glow has been observed around brightly lit cities in nighttime satellite imagery since at least the first publication of large scale maps in the late 1990s. In the literature, this has often been assumed to be an error related to the sensor, and ... More
The Baikal-GVD detector calibrationAug 15 2019In April 2019, the Baikal-GVD collaboration finished the installation of the fourth and fifth clusters of the neutrino telescope Baikal-GVD. Momentarily, 1440 Optical Modules (OM) are installed in the largest and deepest freshwater lake in the world, ... More
Search for cascade events with Baikal-GVDAug 15 2019Baikal-GVD is a next generation, kilometer-scale neutrino telescope currently under construction in Lake Baikal. GVD is formed by multi-megaton sub-arrays (clusters) and is designed for the detection of astrophysical neutrino fluxes at energies from a ... More
The NANOGrav Program for Gravitational Waves and Fundamental PhysicsAug 14 2019We describe the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) and its efforts to directly detect and study gravitational waves and other synergistic physics and astrophysics using radio timing observations of millisecond pulsars. ... More
The NANOGrav Program for Gravitational Waves and Fundamental PhysicsAug 14 2019Aug 16 2019We describe the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) and its efforts to directly detect and study gravitational waves and other synergistic physics and astrophysics using radio timing observations of millisecond pulsars. ... More
A 3-Dimensional Likelihood analysis method for detecting extended sources in VERITASAug 14 2019Gamma ray observations from a few hundred MeV up to tens of TeV are a valuable tool for studying particle acceleration and diffusion within our galaxy. Constructing a coherent physical picture of particle accelerators such as supernova remnants, pulsar ... More
Pixel space convolution for cosmic microwave background experimentsAug 14 2019Cosmic microwave background experiments have experienced an exponential increase in complexity, data size and sensitivity. One of the goals of current and future experiments is to characterize the B-mode power spectrum, which would be considered a strong ... More
A Catalog of Astrophysical Neutrino Candidates for IceCubeAug 14 2019Multi-messenger astrophysics will enable the discovery of new astrophysical neutrino sources and provide information about the mechanisms that drive these objects. We present a curated online catalog of astrophysical neutrino candidates. Whenever single ... More
Near L-edge photoionization of triply charged iron ionsAug 14 2019Relative cross sections for $m$-fold photoionization ($m=1,\ldots,5$) of Fe$^{3+}$ by single photon absorption were measured employing the photon-ion merged-beams setup PIPE at the PETRA III synchrotron light source operated at DESY in Hamburg, Germany. ... More
Sky Brightness Measurements and Ways to Mitigate Light Pollution in Kirksville, MissouriAug 14 2019We describe the level of light pollution in and around Kirksville, Missouri and at Anderson Mesa near Flagstaff, Arizona by measuring the sky brightness using Unihedron sky quality meters. We report that, on average, the Anderson Mesa site is approximately ... More
SkyLLH -- A generalized Python-based tool for log-likelihood analyses in multi-messenger astronomyAug 14 2019Common analysis techniques in multi-messenger astronomy involve hypothesis tests with unbinned log-likelihood (LLH) functions using data recorded in celestial coordinates to identify sources of high-energy cosmic particles in the Universe. We present ... More
Linking the Solar System and Extrasolar Planetary Systems with Radar Astronomy: Infrastructure for "Ground Truth" ComparisonAug 14 2019Planetary radars have obtained unique science measurements about solar system bodies and they have provided orbit determinations allowing spacecraft to be navigated throughout the solar system. Notable results have been on Venus, Earth's "twin," and small ... More
Visible blue-to-red 10 GHz frequency comb via on-chip triple-sum frequency generationAug 14 2019A broadband visible blue-to-red, 10 GHz repetition rate frequency comb is generated by combined spectral broadening and triple-sum frequency generation in an on-chip silicon nitride waveguide. Ultra-short pulses of 150 pJ pulse energy, generated via electro-optic ... More
The Kelvin-Helmholtz instability and smoothed particle hydrodynamicsAug 14 2019There has been interest in recent years to assess the ability of astrophysical hydrodynamics codes to correctly model the Kelvin-Helmholtz instability. Smoothed particle hydrodynamics (SPH), in particular, has received significant attention, though there ... More
The Next Generation of IceCube Realtime Neutrino AlertsAug 13 2019In 2016, IceCube initiated a system of public real-time alerts that are typically issued within one minute, following the detection of a neutrino candidate event that is likely to be of astrophysical origin. The goal of these alerts is to enable multi-messenger ... More
Properties of Radial Velocities measurement based on LAMOST-II Medium-Resolution Spectroscopic ObservationsAug 13 2019The radial velocity (RV) is a basic physical quantity which can be determined through Doppler shift of the spectrum of a star. The precision of RV measurement depends on the resolution of the spectrum we used and the accuracy of wavelength calibration. ... More
Bayesian automated posterior repartitioning for nested samplingAug 13 2019Priors in Bayesian analyses often encode informative domain knowledge that can be useful in making the inference process more efficient. Occasionally, however, priors may be unrepresentative of the parameter values for a given dataset, which can result ... More
Sensitivity Improvements of Very-High-Energy Gamma-Ray Detection with the Upgraded H.E.S.S. I Cameras using Full Waveform ProcessingAug 13 2019The High Energy Stereoscopic System (H.E.S.S.) is an array of five imaging atmospheric Cherenkov telescopes in Namibia observing gamma-rays in the energy range from a few tens of GeV to a few tens of TeV. The Cherenkov signal detected by photomultiplier ... More
Sensitivity Improvements of Very-High-Energy Gamma-Ray Detection with the Upgraded H.E.S.S. I Cameras using Full Waveform ProcessingAug 13 2019Aug 14 2019The High Energy Stereoscopic System (H.E.S.S.) is an array of five imaging atmospheric Cherenkov telescopes in Namibia observing gamma-rays in the energy range from a few tens of GeV to a few tens of TeV. The Cherenkov signal detected by photomultiplier ... More
Response to 'Room Temperature, Quantum-Limited THz Heterodyne Detection? Not Yet'Aug 13 2019This commentary is written in response to arXiv:1907.13198. In this article, Zmuidzinas et al. raise questions about the results reported by our group in Nature Astronomy (DOI: 10.1038/s41550-019-0828-6) regarding our experimental methodology and our ... More
Geometric Distortion Calibration with Photo-lithographic Pinhole Masks for High-Precision AstrometryAug 13 2019Adaptive optics (AO) systems deliver high-resolution images that may be ideal for precisely measuring positions of stars (i.e. astrometry) if the system has stable and well-calibrated geometric optical distortions. A calibration unit, equipped with back-illuminated ... More
The Compton Spectrometer and ImagerAug 12 2019In this Astro2020 APC White Paper, we describe a Small Explorer (SMEX) mission concept called the Compton Spectrometer and Imager. COSI is a Compton telescope that covers the bandpass often referred to as the "MeV Gap" because it is the least explored ... More
On the cosmological performance of photometric classified supernovae with machine learningAug 12 2019The efficient classification of the different types of Supernova is one of the most important problems of the observational cosmology. Spectroscopic confirmation of most objects in upcoming photometric surveys, such as the Dark Energy Survey and the Large ... More
Peering into the Dark (Ages) with Low-Frequency Space InterferometersAug 12 2019Neutral hydrogen pervades the infant Universe, and its redshifted 21-cm signal allows one to chart the Universe. This signal allows one to probe astrophysical processes such as the formation of the first stars, galaxies, (super)massive black holes and ... More
Subsystem Development for the All-Sky Medium Energy Gamma-ray Observatory (AMEGO) prototypeAug 12 2019The gamma-ray sky from several hundred keV to $\sim$ a hundred MeV has remained largely unexplored due to the challenging nature of detecting gamma rays in this regime. At lower energies, Compton scattering is the dominant interaction process whereas ... More
Massive stars in extremely metal-poor galaxies: A window into the pastAug 12 2019Cosmic History has witnessed the lives and deaths of multiple generations of massive stars, all of them invigorating their host galaxies with ionizing photons, kinetic energy, fresh material and stellar-mass black holes. Ubiquitous engines as they are, ... More
Cosmic Ray Extremely Distributed Observatory: Status and perspectives of a global cosmic ray detection frameworkAug 12 2019Aug 19 2019The Cosmic-Ray Extremely Distributed Observatory (CREDO) is a project dedicated to global studies of extremely extended cosmic-ray phenomena, the cosmic-ray ensembles (CRE), beyond the capabilities of existing detectors and observatories. Up to date cosmic-ray ... More
Cosmic Ray Extremely Distributed Observatory: Status and perspectives of a global cosmic ray detection frameworkAug 12 2019Aug 13 2019The Cosmic-Ray Extremely Distributed Observatory (CREDO) is a project dedicated to global studies of extremely extended cosmic-ray phenomena, the cosmic-ray ensembles (CRE), beyond the capabilities of existing detectors and observatories. Up to date cosmic-ray ... More
Cosmic Ray Extremely Distributed Observatory: Status and perspectives of a global cosmic ray detection frameworkAug 12 2019The Cosmic-Ray Extremely Distributed Observatory (CREDO) is a project dedicated to global studies of extremely extended cosmic-ray phenomena, the cosmic-ray ensembles (CRE), beyond the capabilities of existing detectors and observatories. Up to date cosmic-ray ... More
A Study of NaI(Tl) crystal Encapsulation using Organic scintillators for the Dark Matter SearchAug 12 2019Scintillating NaI(Tl) crystals are used for various rare decay experiments, such as dark matter searches. The hygroscopicity of NaI(Tl) crystal makes the construction of crystal detectors in these experiments challenging and requires a tight encapsulation ... More
Prospects for Wideband VLBI Correlation in the CloudAug 12 2019This paper proposes a cloud architecture for the correlation of wide bandwidth VLBI data. Cloud correlation facilitates processing of entire experiments in parallel using flexibly allocated and practically unlimited compute resources. This approach offers ... More
Improved Coupling of Hydrodynamics and Nuclear Reactions via Spectral Deferred CorrectionsAug 10 2019Simulations in stellar astrophysics involve the coupling of hydrodynamics and nuclear reactions under a wide variety of conditions, from simmering convective flows to explosive nucleosynthesis. Numerical techniques such as operator splitting (most notably ... More
High-resolution Infrared Spectrograph for Exoplanet Characterization with the Keck and Thirty Meter TelescopesAug 09 2019HISPEC (High-resolution Infrared Spectrograph for Exoplanet Characterization) is a proposed diffraction-limited spectrograph for the W.M. Keck Observatory, and a pathfinder for the MODHIS facility project (Multi-Object Diffraction-limited High-resolution ... More
Optimising Automatic Morphological Classification of Galaxies with Machine Learning and Deep Learning using Dark Energy Survey ImagingAug 09 2019There are several supervised machine learning methods used for the application of automated morphological classification of galaxies; however, there has not yet been a clear comparison of these different methods using imaging data, or a investigation ... More
Astrophysical measurements with the VERITAS Stellar Intensity InterferometerAug 09 2019Imaging Atmospheric Cherenkov Telescopes have long been viewed as potential light collectors to be used for long baseline optical intensity interferometry observations. Intensity interferometry, as implemented with Cherenkov telescopes, is well suited ... More
On the accuracy of symplectic integrators for secularly evolving planetary systemsAug 09 2019Symplectic integrators have made it possible to study the long-term evolution of planetary systems with direct N-body simulations. In this paper we reassess the accuracy of such simulations by running a convergence test on 20Myr integrations of the Solar ... More
Lunar occultations with Aqueye+ and IqueyeAug 09 2019We report the first-time use of the Aqueye+ and Iqueye instruments to record lunar occultation events. High-time resolution recordings in different filters have been acquired for several occultations taken from January 2016 through January 2018 with Aqueye+ ... More
(Very) Fast astronomical photometry for meter-class telescopesAug 09 2019Our team at the INAF-Astronomical Observatory of Padova and the University of Padova is engaged in the design, construction and operations of instruments with very high time accuracy in the optical band for applications to High Time Resolution Astrophysics ... More
Proving the outstanding capabilities of IACTs in high time resolution optical astronomyAug 09 2019Imaging Atmospheric Cherenkov Telescopes (IACTs) are very-large telescopes designed to detect the nanosecond-timescale flashes produced within extended air showers. Because IACTs are sensitive to the Cherenkov light (UV/blue) and use photodetectors with ... More
Applying matched-filter technique to the search for dark matter transients with networks of quantum sensorsAug 09 2019There are several networks of precision sensors in existence, including networks of atomic clocks, magnetometers, and gravitational wave detectors. These networks can be re-purposed for searches of exotic physics, such as direct dark matter searches. ... More
A Great Successor to the Hubble Space TelescopeAug 08 2019Aug 14 2019The Hubble Space Telescope (HST) has been the most impactful science-driven mission ever flown by NASA. However, when HST reaches the end of its life, there will be a void due to the loss of some of the science capabilities afforded by HST to astronomers ... More
A Great Successor to the Hubble Space TelescopeAug 08 2019The Hubble Space Telescope (HST) has been the most impactful science-driven mission ever flown by NASA. However, when HST reaches the end of its life, there will be a void due to the loss of some of the science capabilities afforded by HST to astronomers ... More
Integral Field Spectroscopy of Green Peas (I): Disentangling disk-like, turbulence and strong outflow kinematics in SDSSJ083843.63+385350.5Aug 08 2019Integral Field Spectroscopy (IFS) is well known for providing detailed insight of extended sources thanks to the possibility of handling space resolved spectroscopic information. Simple and straightforward analysis such as single line fitting yield interesting ... More
Analytic Planetary Transit Light Curves and Derivatives for Stars with Polynomial Limb DarkeningAug 08 2019We derive analytic, closed-form solutions for the light curve of a planet transiting a star with a limb darkening profile which is a polynomial function of the stellar elevation, up to arbitrary integer order. We provide improved analytic expressions ... More
Science opportunities enabled by the era of Visible Band Stellar Imaging with sub-100 μarc-sec angular resolutionAug 08 2019This white paper briefly summarizes stellar science opportunities enabled by ultra-high resolution (sub-100 {\mu} arc-sec) astronomical imaging in the visible (U/V) wavebands. Next generation arrays of Imaging Cherenkov telescopes, to be constructed in ... More
A Fiber Optic Based High Voltage System for Stellar Intensity Interferometry ObservationsAug 08 2019Beginning in Fall 2018, the VERITAS high energy gamma-ray observatory (Amado, AZ) was upgraded to enable Stellar Intensity Interferometry (SII) observations during bright moon conditions. The system potentially allows VERITAS to spatially characterize ... More
GAPS: Searching for Dark Matter using Antinuclei in Cosmic RaysAug 08 2019The General Antiparticle Spectrometer (GAPS) will carry out a sensitive dark matter search by measuring low-energy ($\mathrm{E} < 0.25 \mathrm{GeV/nucleon}$) cosmic ray antinuclei. The primary targets are low-energy antideuterons produced in the annihilation ... More