Latest in astro-ph

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Novel Techniques for Constraining Neutron-Capture Rates Relevant for r-Process Heavy-Element NucleosynthesisApr 22 2019The rapid-neutron capture process ($r$ process) is identified as the producer of about 50\% of elements heavier than iron. This process requires an astrophysical environment with an extremely high neutron flux over a short amount of time ($\sim$ seconds), ... More
The young stellar population in NGC 247 Main properties and hierarchical clusteringApr 22 2019The aim of this work is to investigate the characteristics of the young stellar population in the spiral galaxy NGC 247. In particular, we focused our attention in its hierarchical clustering distributions and the properties of the smallest groups. We ... More
The Scalar Hexaquark $uuddss$: a Candidate for Dark Matter?Apr 22 2019It is conventionally argued that Dark Matter (DM) has a non-baryonic nature, but if we assume that DM was frozen out before primordial nucleosynthesis and could not significantly impact primordial abundances this argument may be evaded. Then a hypothetical ... More
Theoretical foundations of the reduced relativistic gas in the cosmological perturbed contextApr 22 2019The Reduced Relativistic Gas (RRG) is a simplified version of the ideal relativistic gas, which assumes that all particles have the same momentum magnitude. Although this is a very idealized situation, the resulting model preserves the phenomenology of ... More
A tale of two clusters: dynamical history determines disc survival in Tr14 and Tr16 in the Carina NebulaApr 22 2019Understanding how the birthplace of stars affects planet-forming discs is important for a comprehensive theory of planet formation. Most stars are born in dense star-forming regions where the external influence of other stars, particularly the most massive ... More
Chandra, MDM, Swift, and NuSTAR observations confirming the SFXT nature of AX J1949.8+2534Apr 22 2019AX J1949.8+2534 is a candidate supergiant fast X-ray transient (SFXT) observed in outburst by INTEGRAL (IGR J19498+2534). We report on the results of six Neil Gehrels Swift-XRT, one Chandra, and one NuSTAR observation of the source. We find evidence of ... More
Fast orbital shrinkage of black hole X-ray binaries driven by circumbinary disksApr 22 2019Recently, the black hole X-ray binary (BHXB) Nova Muscae 1991 has been reported to be experiencing an extremely rapid orbital decay. So far, three BHXBs have anomalously high orbital period derivatives, which can not be interpreted by the standard stellar ... More
The Hyper Suprime-Cam SSP Transient Survey in COSMOS: OverviewApr 22 2019We present an overview of a deep transient survey of the COSMOS field with the Subaru Hyper Suprime-Cam (HSC). The survey was performed for the 1.77 deg$^2$ ultra-deep layer and 5.78 deg$^2$ deep layer in the Subaru Strategic Program over 6- and 4-month ... More
The Local Volume HI Survey (LVHIS)Apr 21 2019The `Local Volume HI Survey' (LVHIS) comprises deep HI spectral line and 20-cm radio continuum observations of 82 nearby, gas-rich galaxies, supplemented by multi-wavelength images. Our sample consists of all galaxies with Local Group velocities v_LG ... More
Towards Efficient Detection of Small Near-Earth Asteroids Using the Zwicky Transient Facility (ZTF)Apr 21 2019We describe ZStreak, a semi-real-time pipeline specialized in detecting small, fast-moving near-Earth asteroids (NEAs) that is currently operating on the data from the newly-commissioned Zwicky Transient Facility (ZTF) survey. Based on a prototype originally ... More
Surface slopes of asteroid pairs as indicators of mechanical properties and cohesionApr 21 2019Asteroid pairs had a single progenitor that split due to rotational-fission of a weak, rubble-pile structured body. By constructing shape models of asteroid pairs from multiple-apparition observations and using a lightcurve inversion technique, we mapped ... More
Analytic computation of the secular effects of encounters on a binary: features arising from second-order perturbation theoryApr 21 2019Binary-single interactions play a crucial role in the evolution of dense stellar systems such as globular clusters. In addition, they are believed to drive black hole (BH) binary mergers in these systems. A subset of binary-single interactions are secular ... More
TiK-means: $K$-means clustering for skewed groupsApr 21 2019The $K$-means algorithm is extended to allow for partitioning of skewed groups. Our algorithm is called TiK-Means and contributes a $K$-means type algorithm that assigns observations to groups while estimating their skewness-transformation parameters. ... More
The Nucleosynthesis and Reaction Rates of Fluorine 19 ($^{19}F$) in the SunApr 21 2019We investigate the abundance of $^{19}F$ in the Sun through the nucleosynthesis scenario. In addition, we calculate the rate equations and reaction rates of the nucleosynthesis of $^{19}F$ at different temperature scale. Other important functions of this ... More
Can Luminous, Rapidly Evolving Optical Transients be Explained by the Magnetar-powered Stripped Core-Collapse Supernova Model?Apr 21 2019Over the past decade, many rapidly evolving optical transients (REOTs), whose rise and decline timescales are significantly shorter than those of canonical supernovae (SNe), have been discovered and studied. Some REOTs have high peak luminosity ($\gtrsim ... More
Metal-poor stars observed with the automated planet finder telescope. I. Discovery of five carbon-enhanced metal-poor stars from LAMOSTApr 21 2019We report on the discovery of five carbon-enhanced metal-poor (CEMP) stars in the metallicity range of $-3.3<$ [Fe/H] $<-2.4$. These stars were selected from the LAMOST DR3 low-resolution (R$ \sim$ 2,000) spectroscopic database as metal-poor candidates ... More
The Stellar CME-flare relation: What do historic observations reveal?Apr 21 2019Solar CMEs and flares have a statistically well defined relation, with more energetic X-ray flares corresponding to faster and more massive CMEs. How this relation extends to more magnetically active stars is a subject of open research. Here, we study ... More
Spectropolarimetric analysis of an active region filament. I. Magnetic and dynamical properties from single component inversionsApr 21 2019The determination of the magnetic filed vector in solar filaments is possible by interpreting the Hanle and Zeeman effects in suitable chromospheric spectral lines like those of the He I multiplet at 10830 A. We study the vector magnetic field of an active ... More
First astrophysical detection of the helium hydride ion (HeH$^+$)Apr 21 2019During the dawn of chemistry when the temperature of the young Universe had fallen below $\sim$4000 K, the ions of the light elements produced in Big Bang nucleosynthesis recombined in reverse order of their ionization potential. With its higher ionization ... More
A statistical method to detect non-stationarities of gamma-ray burst jetsApr 20 2019We propose a method to detect possible non-stationarities of gamma-ray burst jets. Assuming that the dominant source of variability in the prompt gamma light curve is the non-stationarity of the jet, we show that there should be a connection between the ... More
3-micron Reflectance Spectroscopy of Carbonaceous Chondrites under Asteroid-like ConditionsApr 20 2019We measured 3-micron reflectance spectra of 21 meteorites that represent all carbonaceous chondrite types available in terrestrial meteorite collections. The measurements were conducted at the Laboratory for Spectroscopy under Planetary Environmental ... More
GeV-TeV Cosmic Ray Leptons in the Solar System from the Bow Shock Wind Nebula of the Nearest Millisecond Pulsar J0437-4715Apr 20 2019We consider acceleration of leptons up to GeV-TeV energies in the bow shock wind nebula of PSR J0437-4715 and their subsequent diffusion through the interstellar magnetic fields. The leptons accelerated at the pulsar wind termination surface are injected ... More
3D reconstructions of EUV wave front heights and their influence on wave kinematicsApr 20 2019EUV waves are large-scale disturbances in the solar corona initiated by coronal mass ejections. However, solar EUV images show only the wave fronts projections along the line-of-sight of the spacecraft. We perform 3D reconstructions of EUV wave front ... More
Identification of organic molecules with a laboratory prototype based on the Laser Ablation-CosmOrbitrapApr 20 2019In the Solar System, extra-terrestrial organic molecules have been found on cometary primitive objects, on Titan and Enceladus icy moons and on Mars. Identification could be achieved for simple organic species by remote sensing based on spectroscopic ... More
New powerful outburst of the unusual young star V1318 Cyg S (LkHα 225)Apr 20 2019Young double star V1318 Cyg, which is associated with a small isolated star-forming region around HAeBe star BD+40o4124, has very unusual photometric and spectral behavior. We present results of photometric and spectroscopic observations in the optical ... More
Exoplanet Reflected Light Spectroscopy with PICASOApr 19 2019Here we present the first open-source radiative transfer model for computing the reflected light of exoplanets at any phase geometry, called PICASO: Planetary Intensity Code for Atmospheric Scattering Observations. This code, written in Python, has heritage ... More
On the dynamics of Comet 1P/Halley: Lyapunov and power spectraApr 19 2019Using a purely Newtonian model for the Solar System, we investigate the dynamics of comet 1P/Halley considering in particular the Lyapunov and power spectra of its orbit, using the nominal initial conditions of JPL's Horizons system. We carry out precise ... More
A Search for Pulsed Very High-Energy Gamma Rays from Thirteen Young Pulsars in Archival VERITAS DataApr 19 2019We conduct a search for periodic emission in the very high-energy gamma-ray band (VHE; E > 100 GeV) from a total of 13 pulsars in an archival VERITAS data set with a total exposure of over 450 hours. The set of pulsars includes many of the brightest young ... More
Disentangling nature from nurture: tracing the origin of seed black holesApr 19 2019The origin and properties of black hole seeds that grow to produce the detected population of supermassive black holes are unconstrained at present. Despite the existence of several potentially feasible channels for the production of initial seeds in ... More
A survey of C2H, HCN, and C18O in protoplanetary disksApr 19 2019Molecular lines observed towards protoplanetary disks carry information about physical and chemical processes associated with planet formation. We present ALMA Band 6 observations of C2H, HCN, and C18O in a sample of 14 disks spanning a range of ages, ... More
Astro2020 Science White Paper: Using X-Ray Polarimetry to Probe the Physics of Black Holes and Neutron StarsApr 19 2019This white paper highlights compact object and fundamental physics science opportunities afforded by high-throughput broadband (0.1-60 keV) X-ray polarization observations. X-ray polarimetry gives new observables with geometric information about stellar ... More
Line Ratios Reveal N2H+ Emission Originates Above the Midplane in TW HydraeApr 19 2019Line ratios for different transitions of the same molecule have long been used as a probe of gas temperature. Here we use ALMA observations of the N2H+ J~=~1-0 and J~=~4-3 lines in the protoplanetary disk around TW Hya to derive the temperature at which ... More
Merging galaxies in isolated environments I. Multiband photometry, classification, stellar masses, and star formation ratesApr 19 2019Extragalactic surveys provide significant statistical data for the study of crucial galaxy parameters used to constrain galaxy evolution, e.g. stellar mass (M$_*$) and star formation rate (SFR), under different environmental conditions. These quantities ... More
DarkHistory: A code package for calculating modified cosmic ionization and thermal histories with dark matter and other exotic energy injectionsApr 19 2019We present a new public Python package, DarkHistory, for computing the effects of dark matter annihilation and decay on the temperature and ionization history of the early universe. DarkHistory simultaneously solves for the evolution of the free electron ... More
Characterization of numerical relativity waveforms of eccentric binary black hole mergersApr 19 2019We introduce a method to quantify the initial eccentricity, gravitational wave frequency, and mean anomaly of numerical relativity simulations that describe non-spinning black holes on moderately eccentric orbits. We demonstrate that this method provides ... More
Discovery and Early Evolution of ASASSN-19bt, the First TDE Detected by TESSApr 19 2019We present the discovery and early evolution of ASASSN-19bt, a tidal disruption event (TDE) discovered by the All-Sky Automated Survey for Supernovae at a distance of $d\simeq115$ Mpc and the first TDE to be detected by TESS. As the TDE is located in ... More
Common Envelope Evolution on a Moving MeshApr 19 2019We outline the methodology of simulating common envelope evolution (CEE) with the moving-mesh code MANGA. We extend MANGA to include multiple time-steps. This provides substantial speedups for problems with large dynamic range. We describe the implementation ... More
Photometry of active Centaurs: Colors of dormant active Centaur nucleiApr 19 2019We present multiband photometric observations of nine Centaurs. Five of the targets are known active Centaurs (167P/CINEOS, 174P/Echeclus, P/2008 CL94, P/2011 S1, and C/2012 Q1), and the other four are inactive Centaurs belonging to the redder of the ... More
Ultra Light Boson Dark Matter and Event Horizon Telescope Observations of M87*Apr 19 2019The initial data from the Event Horizon Telescope (EHT) on M87$^*$, the supermassive black hole at the center of the M87 galaxy, provide direct observational information on its mass, spin, and accretion disk properties. A combination of the EHT data and ... More
Effects of winds on the leftover hydrogen in massive stars following Roche-lobe overflowApr 19 2019We find that applying a theoretical wind mass-loss rate from Monte Carlo radiative transfer models for hydrogen-deficient stars results in significantly more leftover hydrogen following stable mass transfer through Roche-lobe overflow than when we use ... More
Non-thermal X-rays from Colliding Wind Shock Acceleration in the Massive Binary Eta CarinaeApr 19 2019Cosmic-ray acceleration has been a long-standing mystery and despite more than a century of study, we still do not have a complete census of acceleration mechanisms. The collision of strong stellar winds in massive binary systems creates powerful shocks, ... More
The digest2 NEO Classification CodeApr 19 2019We describe the digest2 software package, a fast, short-arc orbit classifier for small Solar System bodies. The digest2 algorithm has been serving the community for more than 13 years. The code provides a score, D2, which represents a pseudo-probability ... More
Terrestrial deuterium-to-hydrogen ratio in water in hyperactive cometsApr 19 2019The D/H ratio in cometary water has been shown to vary between 1 and 3 times the Earth's oceans value, in both Oort cloud comets and Jupiter-family comets originating from the Kuiper belt. We present new sensitive spectroscopic observations of water isotopologues ... More
New insight on Young Stellar Objects accretion shocks - a claim for NLTE opacities -Apr 19 2019Context. Accreted material onto CTTSs is expected to form a hot quasi-periodic plasma structure that radiates in X-rays. Simulations of this phenomenon only partly match with observations. They all rely on the assumption that radiation and matter are ... More
Chromospheric polarimetry through multi-line observations of the 850 nm spectral region III: Chromospheric jets driven by twisted magnetic fieldsApr 19 2019We investigate the diagnostic potential of the spectral lines at 850 nm for understanding the magnetism of the lower atmosphere. For that purpose, we use a newly developed 3D simulation of a chromospheric jet to check the sensitivity of the spectral lines ... More
The expectation of cosmic ray proton and helium energy spectrum below 4 PeV measured by LHAASOApr 19 2019Large High Altitude Air Shower Observatory(LHAASO) is a composite cosmic ray observatory consisting of three detector arrays: kilometer square array (KM2A) which includes the electromagnetic detector array and muon detector array, water Cherenkov detector ... More
Secondary CMB temperature anisotropies from magnetic reheatingApr 19 2019Spatially fluctuating primordial magnetic fields~(PMFs) inhomogeneously reheat the Universe when they dissipate deep inside the horizon before recombination. Such an entropy production turns into the additional photon temperature perturbations, in particular, ... More
Long-term spectral study of the black hole Cygnus X-1 using INTEGRALApr 19 2019We utilize the joint capabilities of IBIS and SPI to perform a state-resolved 20--2000\,keV analysis of the microquasar Cygnus X-1. In both LHS and HSS, the spectral analysis reveals the presence of a high-energy tail above 400\,keV in addition to a standard, ... More
Unexpectedly strong effect of supergranulation on the detectability of Earth twins orbiting Sun-like stars with radial velocitiesApr 19 2019Magnetic activity and surface flows at different scales pertub radial velocity measurements. This affects the detectability of low-mass exoplanets. In these flows, the effect of supergranulation is not as well characterized as the other flows, and we ... More
Parameter Estimation for Scarce Stellar PopulationsApr 19 2019We present a Bayesian method to determine simultaneously the age, metallicity, distance modulus, and interstellar reddening by dust of any resolved stellar population, by comparing the observed and synthetic color magnitude diagrams on a star by star ... More
New and Extended Data Processing of Mars Odyssey Neutron Spectrometer DataApr 18 2019The Los Alamos National Laboratory designed and built Mars Odyssey Neutron Spectrometer (MONS) has been in excellent health operating from February 2002 to the present. MONS measures the neutron leakage albedo from galactic cosmic ray bombardment of Mars. ... More
Constraints on a Putative Planet Sculpting the V4046 Sagittarii Circumbinary DiskApr 18 2019We analyze the highest-resolution millimeter continuum and near-infrared (NIR) scattered-light images presented to date of the circumbinary disk orbiting V4046 Sgr, a ~20 Myr old actively accreting, close binary T Tauri star system located a mere 72.4 ... More
Performance of the Gemini Planet Imager Non-Redundant Mask and spectroscopy of two close-separation binaries HR 2690 and HD 142527Apr 18 2019The Gemini Planet Imager (GPI) contains a 10-hole non-redundant mask (NRM), enabling interferometric resolution in complement to its coronagraphic capabilities. The NRM operates both in spectroscopic (integral field spectrograph, henceforth IFS) and polarimetric ... More
Gravitational probes of ultra-light axionsApr 18 2019The axion is a hypothetical, well-motivated dark-matter particle whose existence would explain the lack of charge-parity violation in the strong interaction. In addition to this original motivation, an `axiverse' of ultra-light axions (ULAs) with masses ... More
Observations of Solar Coronal Rain in Null Point TopologiesApr 18 2019Coronal rain is the well-known phenomenon in which hot plasma high in the Sun's corona undergoes rapid cooling (from > 10^6 K to < 10^4 K), condenses, and falls to the surface. Coronal rain appears frequently in active region coronal loops and is very ... More
Sub-GeV Dark Matter Searches and Electric Field Studies for the LUX and LZ ExperimentsApr 18 2019The nature of dark matter (DM) remains a mystery since it has so far eluded detection in the laboratory. To that end, the Large Underground Xenon (LUX) experiment was built to directly observe the interaction of DM with xenon target nuclei. LUX acquired ... More
Atomic Modeling of Photoionization Fronts in Nitrogen GasApr 18 2019Photoionization fronts play a dominant role in many astrophysical environments, but remain difficult to achieve in a laboratory experiment. Recent papers have suggested that experiments using a nitrogen medium held at ten atmospheres of pressure that ... More
The Supersonic Project: Shining Light on SIGOs - a New Formation Channel for Globular ClustersApr 18 2019Supersonically induced gas objects (SIGOs) with little to no dark matter component are predicted to exist in patches of the Universe with non-negligible relative velocity between baryons and the dark matter at the time of recombination. Using {\sc arepo} ... More
Radio spectra and sizes of ALMA-identified submillimetre galaxies: evidence of age-related spectral curvature and cosmic ray diffusion?Apr 18 2019We analyse the multi-frequency radio spectral properties of $41$ 6GHz-detected ALMA-identified, submillimetre galaxies (SMGs), observed at 610MHz, 1.4GHz, 6GHz with GMRT and the VLA. Combining high-resolution ($\sim0.5''$) 6GHz radio and ALMA $870\,\mu$m ... More
Anatomy of a Cooling Flow: The Feedback Response to Pure Cooling in the Core of the Phoenix ClusterApr 18 2019We present new, deep observations of the Phoenix cluster from the Chandra X-ray Observatory, the Hubble Space Telescope, and the Karl Jansky Very Large Array. These data provide an order of magnitude improvement in depth and/or angular resolution at X-ray, ... More
Blue, white, and red ocean planets - Simulations of orbital variations in flux and polarization colorsApr 18 2019An exoplanet's habitability will depend strongly on the presence of liquid water. Flux and/or polarization measurements of starlight that is reflected by exoplanets could help to identify exo-oceans. We investigate which broadband spectral features in ... More
Cosmic-ray transport from AMS-02 B/C data: benchmark models and interpretationApr 18 2019This article aims at establishing new benchmark scenarios for Galactic cosmic-ray propagation in the GV-TV rigidity range, based on fits to the AMS-02 B/C data with the USINE v3.5 propagation code. We employ a new fitting procedure, cautiously taking ... More
Axion-Dilaton Destabilization and the Hubble TensionApr 18 2019The discrepancy in measurements of the Hubble constant indicates new physics in dark energy, dark matter, or both. Drawing inspiration from string theory, where axions interact with the other moduli fields, including the dilaton, here we demonstrate that ... More
Constraining the equation of state of high-density cold matter using nuclear and astronomical measurementsApr 18 2019The increasing richness of data related to cold dense matter, from laboratory experiments to neutron star observations, requires a framework for constraining the properties of such matter that makes use of all relevant information. Here we present a rigorous ... More
Non-ideal MHD simulation of HL Tau disk: formation of ringsApr 18 2019Recent high resolution observations unveil ring structures in circumstellar disks. The origin of these rings has been widely investigated under various theoretical scenarios. In this work we perform global 3D non-ideal MHD simulations including effects ... More
Modelling the periodical variations in multiband polarisation and photometry for discs of binary Be starsApr 18 2019The tidal interaction of a Be star with a binary companion forms two spiral arms that cause orbital modulation of the Be disc structure. The aim of this work is to identify observables in which this modulation is apparent. The structure of a Be disc in ... More
Eigenfunctions of Galactic Phase Space Spirals from Dynamic Mode DecompositionApr 18 2019We introduce the method of Dynamic Mode Decomposition (DMD) to the field of galactic dynamics. In DMD the dynamics of non-linear systems is studied by determining the dominant modes of an approximate linear model for the evolution. Typically, the DMD ... More
The accelerating rotation of the magnetic He-weak star HD 142990Apr 18 2019HD 142990 (V 913 Sco; B5 V) is a He-weak star with a strong surface magnetic field and a short rotation period ($P_{\rm rot} \sim 1$ d). While it is clearly a rapid rotator, recent determinations of $P_{\rm rot}$ are in formal disagreement. In this paper ... More
Nonlinear flavor development of a two-dimensional neutrino gasApr 18 2019We present a numerical survey of the nonlinear flavor development of dense neutrino gases. This study is based on the stationary, two-dimensional ($x$ and $z$), two-beam, monochromatic neutrino line model with a periodic boundary condition along the $x$ ... More
A joint deconvolution algorithm to combine single dish and interferometer data for wideband multi-term and mosaic imagingApr 18 2019Imaging in radio astronomy is usually carried out with a single-dish radio telescope doing a raster scan of a region of the sky or with an interferometer that samples the visibility function of the sky brightness. Mosaic observations are the current standard ... More
Cool spots on the surface of the active giant PZ MonApr 18 2019Based on the multiband (BVRIJHKL) photometric observations of the active red giant PZ Mon performed for the first time in the winter season of 2017-2018, we have determined the main characteristics of the spotted stellar surface in a parametric three-spot ... More
Redshift-weighted constraints on primordial non-Gaussianity from the clustering of the eBOSS DR14 quasars in Fourier spaceApr 18 2019We present constraints on local primordial non-Gaussianity (PNG), parametrized through $f^{\rm loc}_{\rm NL}$, using the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey Data Release 14 quasar sample. We measure and analyze ... More
Shaping Asteroids with Genetic Evolution (SAGE)Apr 18 2019In this work we present SAGE (Shaping Asteroid models using Genetic Evolution) asteroid modelling algorithm based solely on photometric lightcurve data. It produces non-convex shapes, rotation axes orientati and rotational periods of asteroids. The main ... More
Integral constraints in spectroscopic surveysApr 18 2019Current clustering analyses of galaxy surveys rely on the knowledge of the survey selection function. Density fluctuations are estimated by comparing the galaxy density field to a random synthetic catalogue accounting for the survey density and geometry. ... More
All-Sky Near Infrared Space AstrometryApr 18 2019Gaia is currently revolutionizing modern astronomy. However, much of the Galactic plane, center and the spiral arm regions are obscured by interstellar extinction, rendering them inaccessible because Gaia is an optical instrument. An all-sky near infrared ... More
Damping of Propagating Kink Waves in the Solar CoronaApr 18 2019Alfv\'enic waves have gained renewed interest since the existence of ubiquitous propagating kink waves were discovered in the corona. {It has long been suggested that Alfv\'enic} waves play an important role in coronal heating and the acceleration of ... More
Confirming interstellar C$_{60}^+$ using the Hubble Space TelescopeApr 18 2019Recent advances in laboratory spectroscopy lead to the claim of ionized Buckminsterfullerene (C60+) as the carrier of two diffuse interstellar bands (DIBs) in the near-infrared. However, irrefutable identification of interstellar C60+ requires a match ... More
Anomalous Cepheids discovered in a sample of Galactic short period Type II CepheidsApr 18 2019We revisited the short period Type II Cepheids (T2Cs), called the BL Herculis (BLHs), in the Galactic Field to derive a homogeneous analysis of their Fourier parameters. Only V-band data were compiled to make sure that it was directly comparable between ... More
A merger shock in Abell 1367Apr 18 2019Multi-wavelength observations show that Abell 1367 (A1367) is a dynamically young cluster, with at least two subclusters merging along the SE-NW direction. With the wide-field XMM-Newton mosaic of A1367, we discover a previously unknown merger shock at ... More
Debris Disk Composition: A Diagnostic Tool for Planet Formation and MigrationApr 18 2019Debris disks are exoplanetary systems containing planets, minor bodies (such as asteroids and comets) and debris dust. Unseen planets are presumed to perturb the minor bodies into crossing orbits, generating small dust grains that are detected via remote ... More
Why do some probabilistic forecasts lack reliability?Apr 18 2019In this work, we investigate the reliability of the probabilistic binary forecast. We mathematically prove that a necessary, but not sufficient, condition for achieving a reliable probabilistic forecast is maximizing the Peirce skill score (PSS) at the ... More
Structured jets and X-ray plateaus in Gamma-ray BurstsApr 18 2019The first multi-messenger detection of a binary system of neutron stars, GW170817, brought to the forefront the structured jet model as a way to explain multi-wavelength observations taken over one year. Here we show that high-latitude emission (HLE) ... More
Spot evolution on LQ Hya during 2006--2017: temperature maps based on SOFIN and FIES dataApr 18 2019Context. LQ Hya is one of the most frequently studied young solar analogue stars. Recently, it has been observed to show intriguing behaviour by analysing long-term photometry: during 2003--2009, a coherent spot structure migrating in the rotational frame ... More
Convolutional neural networks: a magic bullet for gravitational-wave detection?Apr 18 2019In the last few years, machine learning techniques, in particular convolutional neural networks, have been investigated as a method to replace or complement traditional matched filtering techniques that are used to detect the gravitational-wave signature ... More
The Fornax Deep Survey (FDS) with VST. VI. Optical properties of the dwarf galaxies in the Fornax clusterApr 18 2019The Fornax Deep Survey Dwarf galaxy Catalog (FDSDC) includes 564 dwarf galaxies in the Fornax cluster and the in-falling Fornax A subgroup. We use the FDSDC galaxies for statistical analysis of the structural and stellar population differences in the ... More
Collisionless Energy Transfer in Kinetic Turbulence: Field-Particle Correlations in Fourier SpaceApr 18 2019Turbulence is commonly observed in nearly collisionless heliospheric plasmas, including the solar wind and corona and the Earth's magnetosphere. Understanding the collisionless mechanisms responsible for the energy transfer from the turbulent fluctuations ... More
SkyMapper SEDs of nearby galaxies: quenching and bursting probed by a change index for star formationApr 18 2019The wish list of astronomers includes a tool that reveals quenching of star formation in galaxies directly as it proceeds. Here, we present a proof-of-concept for a new quenching-and-bursting diagnostic, a "change index" for star formation, that requires ... More
Uncovering Red and Dusty Ultraluminous X-ray Sources with SpitzerApr 18 2019We present a mid-infrared (IR) sample study of nearby ultraluminous X-ray sources (ULXs) using multi-epoch observations with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. Spitzer/IRAC observations taken after 2014 were obtained as part ... More
Particle Energy Diffusion in Linear Magnetohydrodynamic WavesApr 18 2019In high-energy astronomical phenomena, the stochastic particle acceleration by turbulences is one of promising processes to generate non-thermal particles. In this paper, providing a temporally evolving wave ensemble, which consists of a single mode (Alfv\'en, ... More
Search for nearby Earth analogs I. 15 planet candidates found in PFS dataApr 18 2019The radial velocity method plays a major role in the discovery of nearby exoplanets. To efficiently find planet candidates from the data obtained in high precision radial velocity surveys, we apply a signal diagnostic framework to detect radial velocity ... More
Vacuum Decay in Real Time and Imaginary Time FormalismsApr 18 2019We analyze vacuum tunneling in quantum field theory in a general formalism by using the Wigner representation. In the standard instanton formalism, one usually approximates the initial false vacuum state by an eigenstate of the field operator, imposes ... More
Kinematics of the OVI Circumgalactic Medium: Halo Mass Dependence and Outflow SignaturesApr 18 2019We probe the high-ionization circumgalactic medium by examining absorber kinematics, absorber-galaxy kinematics, and average absorption profiles of 31 OVI absorbers from the "Multiphase Galaxy Halos" Survey as a function of halo mass, redshift, inclination, ... More
The time-resolved spectra of photospheric emission from a structured jet for gamma-ray burstsApr 17 2019The quasi-thermal components found in many Fermi gamma-ray bursts (GRBs) imply that the photosphere emission indeed contributes to the prompt emission of many GRBs. But whether the observed spectra empirically fitted by the Band function or cutoff power ... More
Astro2020 Science White Paper: Are Supernovae the Dust Producer in the Early Universe?Apr 17 2019Whether supernovae are a significant source of dust has been a long-standing debate. The large quantities of dust observed in high-redshift galaxies raise a fundamental question as to the origin of dust in the Universe since stars cannot have evolved ... More
Supergranular turbulence in a quiet Sun: Lagrangian coherent structuresApr 17 2019The quiet Sun exhibits a wealth of magnetic activities that are fundamental for our understanding of solar and astrophysical magnetism. The magnetic fields in the quiet Sun are observed to evolve coherently, interacting with each other to form distinguished ... More
Fast W-Projection for Wide-field ImagingApr 17 2019Wide-field imaging has become a major challenge for modern radio astronomy, which uses high sensitivity acquisition systems that deal with huge amounts of data. In this paper we investigate a fast wide-field imaging solution based on the w-projection ... More
The Tilt of the Local Velocity Ellipsoid as Seen by GaiaApr 17 2019The Gaia Radial Velocity Spectrometer (RVS) provides a sample of 7,224,631 stars with full six-dimensional phase space information. Bayesian distances of these stars are available from the catalogue of Sch\"onrich et al. (2019). We exploit this to map ... More
Action-based models for dwarf spheroidal galaxies and globular clustersApr 17 2019A new family of self-consistent DF-based models of stellar systems is explored. The stellar component of the models is described by a distribution function (DF) depending on the action integrals, previously used to model the Fornax dwarf spheroidal galaxy ... More
Mars Obliquity History Constrained by Elliptic Crater OrientationsApr 17 2019The dynamics of Mars' obliquity are believed to be chaotic, and the historical ~3.5 Gyr (late-Hesperian onward) obliquity probability density function (PDF) is high uncertain and cannot be inferred from direct simulation alone. Obliquity is also a strong ... More
Astro2020 Science White Paper: Measuring Protostar Masses: The Key to Protostellar EvolutionApr 17 2019Knowledge of protostellar evolution has been revolutionized with the advent of surveys at near-infrared to submillimeter wavelengths. This has enabled the bolometric luminosities and bolometric temperatures (traditional protostellar evolution diagnostics) ... More