Latest in astro-ph.he

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The amplitude of the kilohertz quasi-periodic oscillations in 4U 1636$-$53 in the frequency-energy spaceAug 22 2019We present for the neutron-star low-mass X-ray binary 4U 1636$-$53, and for the first time for any source of kilohertz quasi-periodic oscillations (kHz QPOs), the two-dimensional behaviour of the fractional rms amplitude of the kHz QPOs in the parameter ... More
Searches for steady neutrino emission from 3FHLblazars using eight years of IceCube data from theNorthern hemisphereAug 22 2019Located at the South Pole, the IceCube Neutrino Observatory is the world largest neutrino telescope, instrumenting one cubic kilometre of Antarctic ice at a depth between 1450m to 2450m. In 2013 IceCube reported the first observations of a diffuse astrophysical ... 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
Multi-messenger tests of cosmic-ray acceleration in radiatively inefficient accretion flowsAug 22 2019The cores of active galactic nuclei (AGNs) have been suggested as the sources of IceCube neutrinos, and recent numerical simulations have indicated that hot AGN coronae of Seyfert galaxies and radiatively inefficient accretion flows (RIAFs) of low-luminosity ... More
Puffy accretion disks: sub-Eddington, optically thick, and stableAug 22 2019We report on a new class of solutions of black hole accretion disks that we have found through three-dimensional, global, radiative magnetohydrodynamic simulations in general relativity. It combines features of the canonical thin, slim and thick disk ... More
The gravitational-wave follow-up program of the Cherenkov Telescope ArrayAug 22 2019The birth of gravitational-wave / electromagnetic astronomy was heralded by the joint observation of gravitational waves (GWs) from a binary neutron star (BNS) merger by Advanced LIGO and Advanced Virgo, GW170817, and of gamma-rays from the short gamma-ray ... More
H.E.S.S. searches for TeV gamma rays associated to high-energy neutrinosAug 22 2019The detection of an astrophysical flux of high-energy neutrinos by IceCube is a major step forward in the search for the origin of cosmic rays, as this emission is expected to originate in hadronic interactions taking place in or near cosmic-ray accelerators. ... More
First search for GeV neutrinos from bright gamma-ray solar flares using the IceCube Neutrino ObservatoryAug 22 2019In response to a reported increase in the total neutrino flux in the Homestake experiment in coincidence with solar flares at the end of the eighties, solar neutrino detectors have searched for solar flare signals. Solar flares convert magnetic energy ... More
Probing neutrino emission at GeV energies from compact binary mergers with IceCubeAug 22 2019The advent of Multi-Messenger Astronomy has allowed for new types of source searches within the neutrino community. We present the results of the first search for GeV astrophysical neutrinos emitted from Compact Binary Mergers, i.e. binary black hole ... More
A Sparkler in the Fireworks Galaxy: Discovery of an Ultraluminous X-ray Transient with a Strong Oxygen Line in NGC 6946Aug 22 2019We discovered and studied an ultraluminous X-ray source (CXOU J203451.1+601043) that appeared in the spiral galaxy NGC 6946 at some point between 2008 February and 2012 May, and has remained at luminosities $\approx$2-4 $\times 10^{39}$ erg s$^{-1}$ in ... 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
A short observational view of black hole X-ray binaries with INTEGRALAug 22 2019Accreting black holes are unique tools to understand the physics under extreme gravity. While black hole X-ray binaries differ vastly in mass from AGN, their accretion and ejection flows are assumed to be essentially similar. Black hole X-ray binaries ... More
Searches for point-like sources of cosmic neutrinos with 11 years of ANTARES dataAug 22 2019The main goal of the ANTARES neutrino telescope is the identification of neutrinos from cosmic accelerators. The good visibility towards the Southern sky for neutrino energies below 100 TeV and the good angular resolution for reconstructed events make ... More
Dark matter searches with the IceCube UpgradeAug 22 2019Weakly Interacting Massive Particles (WIMPs) are well-motivated candidates for Dark Matter (DM). WIMP models often include self-annihilation into Standard Model particles such as neutrinos which could potentially be detected by the IceCube Neutrino Observatory. ... More
Discovery of an Outbursting 12.8 Minute Ultracompact X-Ray BinaryAug 22 2019We report the discovery of OGLE-UCXB-01, a 12.8 minute variable object located in the central field of Galactic bulge globular cluster Djorg 2. The presence of frequent, short-duration brightenings at such an ultrashort period in long-term OGLE photometry ... More
Early acceleration of electrons and protons at the nonrelativistic quasiparallel shocks with different obliquity anglesAug 22 2019The early acceleration of protons and electrons in the nonrelativistic collisionless shocks with three obliquities are investigated through 1D particle-in-cell simulations. In the simulations, the charged particles possessing a velocity of $0.2\, c$ flow ... More
X-ray Intra-day Variability of the TeV Blazar Mrk 421 with SuzakuAug 22 2019We present X-ray flux and spectral analyses of the three pointed Suzaku observations of the TeV high synchrotron peak blazar Mrk 421 taken throughout its complete operational duration. The observation taken on 5 May 2008 is, at 364.6 kiloseconds (i.e., ... More
Cosmic Ray Spectrum and Composition from PeV to EeV from the IceCube Neutrino ObservatoryAug 21 2019The IceCube Neutrino Observatory at the South Pole is a multi-component detector capable of measuring the cosmic ray energy spectrum and composition from PeV to EeV, the energy region typically thought to cover the transition from galactic to extragalactic ... More
Kinetic Simulations of Radiative Magnetic Reconnection in the Magnetized Coronae of Accreting Black HolesAug 21 2019We perform two-dimensional particle-in-cell simulations of reconnection in magnetically dominated electron-positron plasmas subject to strong Compton cooling. Magnetic reconnection under such conditions can operate in accretion disk coronae around black ... More
X-ray properties of z>4 blazarsAug 21 2019We present the X-ray analysis of the largest flux-limited complete sample of blazar candidates at z>4 selected from the Cosmic Lens All Sky Survey (CLASS). After obtaining a nearly complete (24/25) X-ray coverage of the sample (from Swift-XRT, XMM-Newton ... More
Consistency of the Infrared Variability of Sgr A* over 22 yearsAug 21 2019We report new infrared measurements of the supermassive black hole at the Galactic Center, Sgr A*, over a decade that was previously inaccessible at these wavelengths. This enables a variability study that addresses variability timescales that are ten ... More
A search for IceCube events in the direction of ANITA neutrino candidatesAug 21 2019The Antarctic Impulsive Transient Antenna (ANITA) collaboration has reported a total of three neutrino candidates from the experiment's first three flights. One of these was the lone candidate in a search for Askaryan radio emission, and the others can ... More
The Progenitors of Calcium-Strong TransientsAug 21 2019A new class of faint, spectroscopically peculiar transients has emerged in the last decade. We term these events "calcium-strong transients" (CaSTs) because of their atypically high calcium-to-oxygen nebular line ratios. Previous studies have struggled ... More
The Optical Afterglow of GW170817: An Off-axis Structured Jet and Deep Constraints on a Globular Cluster OriginAug 21 2019We present a revised and complete optical afterglow light curve of the binary neutron star merger GW170817, enabled by deep Hubble Space Telescope (HST) F606W observations at $\approx\!584$ days post-merger, which provide a robust optical template. The ... More
Kinetic turbulence in shining pair plasma: intermittent beaming and thermalization by radiative coolingAug 21 2019High-energy astrophysical systems frequently contain collisionless relativistic plasmas that are heated by turbulent cascades and cooled by emission of radiation. Understanding the nature of this radiative turbulence is a frontier of extreme plasma astrophysics. ... More
A NICER Look at Strong X-ray Obscuration in the Seyfert-2 Galaxy NGC 4388Aug 21 2019We present an analysis of the time-averaged spectrum of the Seyfert-2 active galaxy NGC 4388, obtained by NICER. The intrinsic strength of the reflection spectrum in NGC 4388, the large collecting area and favorable pass band of NICER, and a net exposure ... More
Glitching pulsars: unraveling the interactions of general relativity with quantum fields in the strong field regimesAug 21 2019We present a modification of our previous model for the mechanisms underlying the glitch phenomena in pulsars and young neutron stars. Accordingly, pulsars are born with embryonic cores comprising of purely incompressible superconducting gluon-quark superfluid ... More
Main trends of the quasar main sequence -- effect of viewing angleAug 21 2019We address the effect of the viewing angle of the accretion disk plane and the geometry of the broad-line region (BLR) with the goal of interpreting the distribution of quasars along the main sequence (MS). We utilize photoionization code CLOUDY to model ... 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
The lateral distribution function of cosmic-ray induced air showers studied with the HAWC observatoryAug 21 2019The particle lateral distribution function (LDF) of air showers at a given altitude is sensitive to the mass composition and primary energy of cosmic rays. Studies of the LDF are difficult to perform due to experimental effects such as sampling bias, ... More
Electron acceleration in non-relativistic quasi-perpendicular collisionless shocksAug 21 2019We study diffusive shock acceleration (DSA) of electrons in non-relativistic quasi-perpendicular shocks using self-consistent one-dimensional particle-in-cell (PIC) simulations. By exploring the parameter space of sonic and Alfv\'{e}nic Mach numbers we ... More
SN 2018hna: 1987A-like supernova with a signature of shock breakoutAug 21 2019High cadence ultraviolet, optical and near-infrared photometric and low-resolution spectroscopic observations of the peculiar Type II supernova (SN) 2018hna are presented. The early phase multiband light curves exhibit the adiabatic cooling envelope emission ... More
Six-dimensional Myers-Perry rotating black hole cannot be overspunAug 21 2019Though under non-linear accretion, all black holes in four and higher dimensions obey the weak Cosmic Censorship Conjecture, however they generally violate it for the linear test particle accretion with the exception of five dimensional rotating black ... More
Supernova lightCURVE POPulation Synthesis II: Validation against supernovae with an observed progenitorAug 21 2019We use the results of a supernova light-curve population synthesis to predict the range of possible supernova light curves arising from a population of single-star progenitors that lead to type IIP supernovae. We calculate multiple models varying the ... More
Blast Waves from Magnetar Flares and Fast Radio BurstsAug 21 2019Magnetars younger than one century are expected to be hyper active. Besides winds powered by rotation they generate frequent magnetic flares, which launch powerful blast waves into the wind. These internal shocks act as masers producing fast (millisecond) ... 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
XMM-Newton observations of the symbiotic recurrent nova T CrB: evolution of X-ray emission during the active phaseAug 21 2019We present an analysis of the XMM-Newton observations of the symbiotic recurrent nova T CrB, obtained during its active phase that started in 2015. The XMM-Newton spectra of T CrB have two prominent components: a soft one (0.2 - 0.6 keV), well represented ... More
Search for very-high-energy photons from Gamma-ray bursts with HAWCAug 21 2019Detections of very-high-energy (VHE; > 100 GeV) photons from Gamma-ray bursts (GRBs) can provide fundamental information on the involved radiative processes, physical composition of the ejecta and acceleration processes. The High Altitude Water Cherenkov ... More
A Search for IceCube Neutrinos from the First 33 Detected Gravitational Wave EventsAug 21 2019The discoveries of high-energy astrophysical neutrinos by IceCube in 2013 and of gravitational waves by LIGO in 2015 have enabled a new era of multi-messenger astronomy. Gravitational waves can identify the merging of compact objects such as neutron stars ... More
Radio Pulsar Sub-Populations (I) : The Curious Case of Nulling PulsarsAug 21 2019About 200 radio pulsars have been observed to exhibit nulling episodes - short and long. In this work, we consider the general characteristics of this sub-population of radio pulsars. It appears that the phenomenon of nulling may be preferentially experience ... 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
Spallation-altered accreted compositions for X-ray bursts: Impact on ignition conditions and burst ashesAug 20 2019Dependable predictions of the X-ray burst ashes and light curves require a stringent constraint on the composition of the accreted material as an input parameter. Lower metallicity models are generally based on a metal deficient donor and all metals are ... 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
Quest for new physics using astrophysical neutrino flavor in IceCubeAug 20 2019We have detected astrophysical neutrinos in IceCube that can be used to probe astrophysical sources at ultra high scales. Here we report a search for anomalous space time effects using astrophysical neutrino flavor data in IceCube. New effective operators ... More
Quest for new physics using astrophysical neutrino flavor in IceCubeAug 20 2019Aug 22 2019We have detected astrophysical neutrinos in IceCube that can be used to probe astrophysical sources at ultra high scales. Here we report a search for anomalous space time effects using astrophysical neutrino flavor data in IceCube. New effective operators ... More
A Three-dimensional Reconstruction of Cosmic Ray Events in IceCubeAug 20 2019The IceCube Neutrino Observatory at the geographic South Pole consists of two components, a km2 surface array IceTop and a km3 in-ice array between 1.5 and 2.5 km below the surface. Cosmic ray events with primary energy above a few tens of TeV may trigger ... More
Sensitivity of Super-Kamiokande with Gadolinium to Low Energy Anti-neutrinos from Pre-supernova EmissionAug 20 2019Supernova detection is a major objective of the Super-Kamiokande (SK) experiment. In the next stage of SK (SK-Gd), gadolinium (Gd) sulfate will be added to the detector, which will improve the ability of the detector to identify neutrons. A core-collapse ... More
BAT AGN Spectroscopic Survey -- XIII. The nature of the most luminous obscured AGN in the low-redshift universeAug 20 2019We present a multi wavelength analysis of 28 of the most luminous low-redshift narrow-line, ultra-hard X-ray selected active galactic nuclei (AGN) drawn from the 70 month Swift/BAT all-sky survey, with bolometric luminosities of log(L_bol/erg/s) > 45.25. ... 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
Do three-body encounters in galactic nuclei affect compact binary merger rates?Aug 20 2019High-density cusps of compact remnants are expected to form around supermassive black holes (SMBHs) in galactic nuclei via dynamical friction and two-body relaxation. Due to the high density, binaries in orbit around the SMBH can frequently undergo close ... More
Linear spectropolarimetry of 35 Type Ia Supernovae with VLT/FORS: An analysis of the Si II line polarizationAug 20 2019Spectropolarimetry enables us to measure the geometry and chemical structure of the ejecta in supernova explosions, which is fundamental for the understanding of their explosion mechanism(s) and progenitor systems. We collected archival data of 35 Type ... More
Particle acceleration in a nearby galaxy cluster pair: the role of cluster dynamicsAug 20 2019Diffuse radio emission associated with the intra-cluster medium (ICM) is observed in a number of merging galaxy clusters. It is currently believed that in mergers a fraction of the kinetic energy is channeled into non-thermal components, such as turbulence, ... More
Galactic Cosmic Ray Sun Shadow during the declining phase of cycle 24 observed by HAWCAug 20 2019The High Altitude Water Cherenkov (HAWC) array is sensitive to high energy Cosmic Rays (CR) in the $\sim 10$ to $\sim 200$ TeV energy range, making it possible to construct maps of the so called "Sun Shadow" ($SS$), i. e. of the deficit of CR coming from ... More
Searching for optical and VHE counterparts of fast radio bursts with MAGICAug 20 2019Fast radio bursts (FRBs) are an enigmatic class of extragalactic transients emitting Jy-level radio bursts in the GHz band, lasting for only a few ms. So far, some objects are known to repeat while several others are not, likely indicating multiple origins. ... 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
ANTARES and IceCube combined search for neutrino point-like and extended sources in the Southern SkyAug 20 2019The ANTARES neutrino telescope, located in the Mediterranean Sea, and the IceCube neutrino observatory, located at the geographic South Pole, both search for cosmic neutrino events with an instantaneous full-sky field of view. The different characteristics ... More
Optical follow-up of the tidal disruption event iPTF16fnl: new insights from X-shooter observationsAug 20 2019We present the results from Nordic Optical Telescope and X-shooter follow-up campaigns of the tidal disruption event (TDE) iPTF16fnl, covering the first $\sim$100 days after the transient discovery. We followed the source photometrically until the TDE ... More
Time-Reversed Gamma-Ray Burst Light Curve Characteristics as Transitions between Subluminal and Superluminal MotionAug 20 2019We introduce a simple model to explain the time-reversed and stretched residuals in gamma-ray burst (GRB) pulse light curves. In this model an impactor wave in an expanding GRB jet accelerates from subluminal to superluminal velocities, or decelerates ... More
Combined Search for Neutrinos from Dark Matter Annihilation in the Galactic Centre using ANTARES and IceCubeAug 20 2019The ANTARES and IceCube neutrino telescopes have both searched for neutrinos from dark matter annihilation in the Galactic Centre, putting limits on the thermally-averaged dark matter self-annihilation cross section $\langle \sigma_A \upsilon \rangle$. ... More
High Density Reflection Spectroscopy: II. the Density of the Inner Black Hole Accretion Disc in AGNAug 20 2019Aug 21 2019We present a high density disc reflection spectral analysis of a sample of 17 Seyfert 1 galaxies to study the inner disc densities at different black hole mass scales and accretion rates. All the available XMM-Newton observations in the archive are used. ... More
High Density Reflection Spectroscopy: II. the Density of the Inner Black Hole Accretion Disc in AGNAug 20 2019We present a high density disc reflection spectral analysis of a sample of 17 Seyfert 1 galaxies to study the inner disc densities at different black hole mass scales and accretion rates. All the available XMM-Newton observations in the archive are used. ... 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
Search for dark matter annihilation in the center of the Earth with 8 years of IceCube dataAug 20 2019Dark matter particles in the galactic halo can scatter off particles in celestial bodies such as stars or planets, lose energy and become gravitationally trapped. In this process, an accumulation of dark matter in the center of celestial bodies is expected, ... More
Eleven Year Search for Supernovae with the IceCube Neutrino ObservatoryAug 20 2019The IceCube Neutrino Observatory, which instruments 1$\,$km$^3$ of clear ice at the geographic South Pole, was mainly designed to detect particles with energies in the multi-GeV to PeV range. Due to ice temperatures between $-20^\circ$C to $-43^\circ$C ... More
Non-thermal emission from cosmic rays accelerated in HII regionsAug 20 2019Aug 21 2019Radio observations at metre-centimetre wavelengths shed light on the nature of the emission of HII regions. Usually this category of objects is dominated by thermal radiation produced by ionised hydrogen, namely protons and electrons. However, a number ... More
Non-thermal emission from cosmic rays accelerated in HII regionsAug 20 2019Radio observations at metre-centimetre wavelengths shed light on the nature of the emission of HII regions. Usually this category of objects is dominated by thermal radiation produced by ionised hydrogen, namely protons and electrons. However, a number ... More
Search for dark matter with metastable mediators with the IceCube observatoryAug 20 2019The IceCube neutrino observatory is a 3D array of photodetectors installed in the Antarctic ice. It consists of 5,160 photomultiplier-tubes spread among 86 vertical strings making a total detector volume of more than a cubic kilometer. It detects neutrinos ... 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
Force-free electrodynamics near rotation axis of a Kerr black holeAug 20 2019Despite their potential importance for understanding astrophysical jets, physically realistic exact solutions for magnetospheres around Kerr black holes have not been found, even in the force-free approximation. Instead approximate analytical solutions ... More
Diagnosing Cosmic Ray Modified Shocks with H α PolarimetryAug 20 2019A novel diagnostic of cosmic-ray modified shocks by polarimetry of H $\alpha$ emissions is suggested. In a cosmic-ray modified shock, the pressure of cosmic rays is sufficiently high compared to the upstream ram pressure to force the background plasma ... More
Potential Kick Velocity distribution of black hole X-ray binaries and implications for natal kicksAug 20 2019We use Very Long Baseline Interferometry to measure the proper motions of three black hole X-ray binaries (BHXBs). Using these results together with data from the literature and Gaia-DR2 to collate the best available constraints on proper motion, parallax, ... More
Low Energy Cosmic Ray Spectrum from 250 TeV to 10 PeV using IceTopAug 20 2019Using IceTop, the surface component of the IceCube Neutrino Observatory, the all-particle cosmic ray energy spectrum has been determined above a few PeV. The measured energy spectrum leaves a gap of more than a decade in energy to direct measurements ... More
The Origin of the X-ray Emission in Two Well-Aligned Extragalactic Jets: The Case for IC/CMBAug 20 2019Aug 22 2019Over the past two decades, the most commonly adopted explanation for high and hard X-ray emission in resolved quasar jets has been inverse Compton upscattering of the Cosmic Microwave Background (IC/CMB), which requires jets which remain highly relativistic ... More
The Origin of the X-ray Emission in Two Well-Aligned Extragalactic Jets: The Case for IC/CMBAug 20 2019Over the past two decades, the most commonly adopted explanation for high and hard X-ray emission in resolved quasar jets has been inverse Compton upscattering of the Cosmic Microwave Background (IC/CMB), which requires jets which remain highly relativistic ... More
Parameterized and Consistency Tests of Gravity with Gravitational Waves: Current and FutureAug 19 2019Gravitational wave observations offer unique opportunities to probe gravity in the strong and dynamical regime, which was difficult to access previously. We here review two theory-agnostic ways to carry out tests of general relativity with gravitational ... 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
Measurement of the high-energy all-flavor neutrino-nucleon cross section with IceCubeAug 19 2019The flux of high-energy neutrinos passing through the Earth is attenuated due to their interactions with matter. Their transmission probability is modulated by the neutrino interaction cross section and affects the arrival flux at the IceCube Neutrino ... More
IceTop as veto for IceCube: resultsAug 19 2019The IceCube Neutrino Observatory features both a kilometer-cubed detector between 1.45 and 2.45 km depth and an array of ice-filled tanks, called IceTop, located at the surface. The presence of both detectors at the same location allows for detailed studies ... More
Early supernova emission -- logarithmic corrections to the planar phaseAug 19 2019When the shock wave generated in a supernova explosion breaks out of the stellar envelope, the first photons, typically in the X-ray to UV range, escape to the observer. Following this breakout emission, radiation from deeper shells diffuses out of the ... More
Probing the Survival of Planetary Systems in Globular Clusters with Tidal Disruption EventsAug 19 2019Among the growing list of confirmed exoplanets, the number of planets identified in dense star clusters remains sparse. Previous analyses have suggested this may be due in part to dynamical interactions that unbind large fractions of planets from their ... More
Probing the Survival of Planetary Systems in Globular Clusters with Tidal Disruption EventsAug 19 2019Aug 22 2019Among the growing list of confirmed exoplanets, the number of planets identified in dense star clusters remains sparse. Previous analyses have suggested this may be due in part to dynamical interactions that unbind large fractions of planets from their ... More
Multi-wavelength observation of MAXI J1820+070 with MAGIC, VERITAS and H.E.S.SAug 19 2019MAXI J1820+070 is a new low-mass microquasar hosting a black hole recently discovered in X-rays by the MAXI instrument. It is the counterpart of ASASSN-18ey, discovered in optical a few days before by ASAS-SN. This source underwent a major outburst in ... More
Frequency drifts in FRBs due to radius-to-frequency mapping in magnetospheres of neutron starsAug 19 2019We interpret recent observations of high-to-low frequency drifting features in the spectra of the repeating FRBs as evidence of sharply changing plasma properties in the emission region, presumably the neutron stars magnetospheres. The drifts are then ... More
Neutrino Fluence from Gamma-Ray Bursts: Off-Axis View of Structured JetsAug 19 2019We investigate the expected high-energy neutrino fluence from internal shocks produced in the relativistic outflow of gamma-ray bursts. Previous model predictions have primarily focussed on on-axis observations of uniform jets. Here we present a generalization ... More
Physics of Pair Producing Gaps in Black Hole Magnetospheres II -- General RelativityAug 19 2019This is the second paper in a series where we examine the physics of pair producing gaps in low-luminosity accreting supermassive black hole systems. In this paper, we carry out time-dependent self-consistent fully general relativistic 1D PIC simulations ... More
A survey of Active Galaxies with the HAWC Gamma-ray ObservatoryAug 19 2019The High Altitude Water Cherenkov Gamma-Ray Observatory has been accumulating a progressively deeper exposure of the TeV sky since its inauguration in March 2015. Located at geographical latitude $+19^\circ$N, HAWC has been able to perform a deep and ... More
Observations of blazar PKS 2023-07 in flaring state with HESS and Fermi-LAT in 2016-2017 and constraints on an intrinsic cut-offAug 19 2019PKS 2023-07 is a flat spectrum radio quasar located at a redshift $z=1.388$, farther than any source currently detected at very high energies ($E>100$ GeV). At such energies, absorption by the extragalactic background light (EBL) renders the detection ... More
Effects of Radiation in Accretion Regions of Classical T Tauri Stars: Pre-heating of accretion column in non-LTE regimeAug 19 2019Models and observations indicate that the impact of matter accreting onto the surface of young stars produces regions at the base of accretion columns, in which optically thin and thick plasma components coexist. Thus an accurate description of these ... More
Effects of Radiation in Accretion Regions of Classical T Tauri Stars: Pre-heating of accretion column in non-LTE regimeAug 19 2019Aug 20 2019Models and observations indicate that the impact of matter accreting onto the surface of young stars produces regions at the base of accretion columns, in which optically thin and thick plasma components coexist. Thus an accurate description of these ... More
Observations of the FSRQ 3C 279 during the flaring state of 2017 and 2018 with H.E.S.SAug 19 2019The Flat Spectrum Radio Quasar 3C 279 has been very active since a few years with multiple flaring events occurring at high energies. As part of the H.E.S.S. Target of Opportunity program, 3C 279 was observed multiple times in 2017 and 2018 following ... More
Bondi accretion in the finite luminous region of elliptical galaxiesAug 19 2019The classical Bondi model is adopted to study accretion onto the finite luminous region around the central massive black hole (MBH) in an elliptical galaxy. Unlike Bondi (1952), we define the boundary conditions at a certain finite radius ($r_f$) instead ... More
Searches for counterparts of gravitational waves at very high energies with H.E.S.SAug 19 2019The recent milestones in multi-messenger astronomy have opened new ways to study the Unverse. The unprecedented gravitational wave (GW) follow-up campaigns established the power that the combination of different messengers has to identify and study the ... More
A complementary view of the Galactic plane in TeV gamma rays by HAWC and H.E.S.SAug 19 2019The H.E.S.S. collaboration recently published its Galactic Plane Survey, which is a deep survey of half of the Milky Way in TeV gamma-rays, using almost 10 years of observations. It contains 78 sources, including 16 new sources. On the other hand, the ... More
IceCube search for high-energy neutrinos produced in the precursor stages of gamma-ray burstsAug 19 2019While gamma-ray bursts (GRBs) were once believed to be a dominant source of astrophysical neutrinos, the lack of any significant correlation between high-energy photons and neutrinos has resulted in stringent limits on their neutrino fluxes. Previous ... 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
The beamed jet and quasar core of the distant blazar 4C 71.07Aug 19 2019The object 4C 71.07 is a high-redshift blazar whose spectral energy distribution shows a prominent big blue bump and a strong Compton dominance. We present the results of a two-year multiwavelength campaign led by the Whole Earth Blazar Telescope (WEBT) ... More
Measurement of the Diffuse Muon Neutrino Fluxusing Starting Track Events in IceCubeAug 19 2019IceCube measures the diffuse neutrino flux across several neutrino flavors and energy ranges. ESTES focuses on the measurement of the diffuse neutrino flux using high purity astrophysical muon neutrinos with energies above 1 TeV. We use the Enhanced Starting ... More
Characterization of diffuse X-ray emission from IGR~J17448-3232: an implication of a line of sight merging activityAug 19 2019Results of the spectral analysis for the galaxy cluster IGR J17448-3232 are presented. The intracluster medium (ICM) in the central region (r<300", 320 kpc) has a high electron temperature plasma of kTe~13-15 keV and an ionization temperature estimated ... More