text stringlengths 89 2.49k | category stringclasses 19
values |
|---|---|
Comptonization by Reconnection Plasmoids in Black Hole Coronae III:
Dependence on the Guide Field in Pair Plasma: We perform two-dimensional particle-in-cell simulations of magnetic
reconnection for various strengths of the guide field (perpendicular to the
reversing field), in magnetically-dominated electron-positro... | astro-ph_HE |
NGC 4388: A Test Case for Relativistic Disk Reflection and Fe K
Fluorescence Features: We present a new analysis of the Suzaku X-ray spectrum of the Compton-thin
Seyfert 2 galaxy NGC 4388. The spectrum above $\sim$2 keV can be described by a
remarkably simple and rather mundane model, consisting of a uniform, neutral... | astro-ph_HE |
Optical photometry and spectroscopy of the low-luminosity, broad-lined
Ic supernova iPTF15dld: Core-collapse stripped-envelope supernova (SN) explosions reflect the
diversity of physical parameters and evolutionary paths of their massive star
progenitors. We have observed the type Ic SN iPTF15dld (z = 0.047), reporte... | astro-ph_HE |
Spin down during quiescence of the fastest known accretion-powered
pulsar: We present a timing solution for the 598.89 Hz accreting millisecond pulsar,
IGR J00291+5934, using Rossi X-ray Timing Explorer data taken during the two
outbursts exhibited by the source on 2008 August and September. We estimate the
neutron s... | astro-ph_HE |
Multi-wavelength Photometry and Progenitor Analysis of the Nova V906 Car: We present optical and infrared photometry of the classical nova V906 Car,
also known as Nova Car 2018 and ASASSN-18fv, discovered by ASASS-SN survey on
16.32 March 2018 UT (MJD 58193.0). The nova reached its maximum on MJD 58222.56
at $V_{\rm{ma... | astro-ph_HE |
Swift monitoring of the central X-ray source in RCW 103: The X-ray source 1E 161348-5055 lies at the centre of the 2-kyr-old supernova
remnant RCW 103. Owing to its 24-ks modulation, orders-of-magnitude flux
variability over a few months/years, and lack of an obvious optical
counterpart, 1E 161348-5055 defies assignmen... | astro-ph_HE |
Between the cosmic-ray `knee' and the `ankle': Contribution from star
clusters: We show that massive young star clusters may be possible candidates that can
accelerate Galactic cosmic rays (CRs) in the range of $10^7\hbox{--}10^9$ GeV
(between the `knee' and `ankle'). Various plausible scenarios such as
acceleration ... | astro-ph_HE |
Detection of X-ray flares from AX J1714.1-3912, the unidentified source
near RX J1713.7-3946: Molecular clouds are predicted to emit nonthermal X-rays when they are close
to particle-accelerating supernova remnants (SNRs), and the hard X-ray source
AX J1714.1-3912, near the SNR RX J1713.7-3946, has long been consider... | astro-ph_HE |
Neutrino-Driven Outflows and the Elemental Abundance Patterns of Very
Metal-Poor Stars: The elemental abundances between strontium and silver ($Z = 38-47$) observed
in the atmospheres of very metal-poor stars (VMP) in the Galaxy may contain the
fingerprint of the weak $r$-process and $\nu p$-process occurring in earl... | astro-ph_HE |
Progenitors and Explosion Properties of Supernova Remnants Hosting
Central Compact Objects: I. RCW 103 Associated with the Peculiar Source 1E
161348-5055: We present a Chandra and XMM-Newton imaging and spectroscopic study of the
supernova remnant (SNR) RCW 103 (G332.4-00.4) containing the Central Compact
Object 1E... | astro-ph_HE |
Inflows, Outflows, and a Giant Donor in the Remarkable Recurrent Nova
M31N 2008-12a? - Hubble Space Telescope Photometry of the 2015 Eruption: The recurrent nova M31N 2008-12a experiences annual eruptions, contains a
near-Chandrasekhar mass white dwarf, and has the largest mass accretion rate in
any nova system. In t... | astro-ph_HE |
Simultaneous X-ray, gamma-ray, and Radio Observations of the repeating
Fast Radio Burst FRB 121102: We undertook coordinated campaigns with the Green Bank, Effelsberg, and
Arecibo radio telescopes during Chandra X-ray Observatory and XMM-Newton
observations of the repeating fast radio burst FRB 121102 to search for
s... | astro-ph_HE |
MAGIC observations provide compelling evidence of the hadronic multi-TeV
emission from the putative PeVatron SNR G106.3+2.7: The SNR G106.3+2.7, detected at 1--100 TeV energies by different $\gamma$-ray
facilities, is one of the most promising PeVatron candidates. This SNR has a
cometary shape which can be divided in... | astro-ph_HE |
A JWST Near- and Mid-Infrared Nebular Spectrum of the Type Ia Supernova
2021aefx: We present JWST near- and mid-infrared spectroscopic observations of the
nearby normal Type Ia supernova SN 2021aefx in the nebular phase at $+255$ days
past maximum light. Our Near Infrared Spectrograph (NIRSpec) and Mid Infrared
Instr... | astro-ph_HE |
The Varying Kinematics of Multiple Ejecta from the Black Hole X-ray
Binary MAXI J1820+070: During a 2018 outburst, the black hole X-ray binary MAXI J1820+070 was
comprehensively monitored at multiple wavelengths as it underwent a hard to
soft state transition. During this transition a rapid evolution in X-ray timing
... | astro-ph_HE |
Predicting Short-duration GRB Rates in the Advanced LIGO Volume: Starting with models for the compact object merger event rate, the
short-duration Gamma-ray Burst (sGRB) luminosity function, and the Swift/BAT
detector, we calculate the observed Swift sGRB rate and its uncertainty. Our
probabilistic sGRB world model rep... | astro-ph_HE |
The unreasonable weakness of r-process cosmic rays in the
neutron-star-merger nucleosynthesis scenario: We reach the robust conclusion that, by combining the observed cosmic rays of
r-process elements with the fact that the velocity of the neutron-star-merger
ejecta is much higher than that of the supernova ejecta, e... | astro-ph_HE |
Formation of Lower Mass-gap Black Hole--Neutron Star Binary Mergers
through Super-Eddington Stable Mass Transfer: Super-Eddington accretion of neutron stars (NSs) has been suggested both
observationally and theoretically. In this paper, we propose that NSs in
close-orbit binary systems with companions of helium (He) ... | astro-ph_HE |
Long-term multi-wavelength study of 1ES 0647+250: The BL Lac object 1ES 0647+250 is one of the few distant $\gamma$-ray
emitting blazars detected at very high energies (VHE, $\gtrsim$100 GeV) during
a non-flaring state. It was detected with the MAGIC telescopes during its low
activity in the years 2009-2011, as well as... | astro-ph_HE |
Energetic Gamma Radiation from Rapidly Rotating Black Holes: Supermassive black holes are believed to be the central power house of active
galactic nuclei. Applying the pulsar outer-magnetospheric particle accelerator
theory to black-hole magnetospheres, we demonstrate that an electric field is
exerted along the magnet... | astro-ph_HE |
Magnetar as the Central Engine of AT2018cow: Optical, Soft X-Ray, and
Hard X-Ray Emission: AT2018cow is the most extensively observed and widely studied fast blue
optical transient to date; its unique observational properties challenge all
existing standard models. In this paper, we model the luminosity evolution of
... | astro-ph_HE |
K-shell photoionization of Nickel ions using R-matrix: We present R-matrix calculations of photoabsorption and photoionization cross
sections across the K edge of the Li-like to Ca-like ions stages of Ni.
Level-resolved, Breit-Pauli calculations were performed for the Li-like to
Na-like stages. Term-resolved calculatio... | astro-ph_HE |
Chandra observations of NGC4342, an optically faint, X-ray gas-rich
early-type galaxy: Chandra X-ray observations of NGC4342, a low stellar mass (M_K=-22.79 mag)
early-type galaxy, show luminous, diffuse X-ray emission originating from hot
gas with temperature of kT~0.6 keV. The observed 0.5-2 keV band luminosity of
... | astro-ph_HE |
Gamma-Ray Burst long lasting X-ray flaring activity: In this paper we shed light on late time (i.e. with peak time t_{pk} \gtrsim
1000 s) flaring activity. We address the morphology and energetic of flares in
the window \sim 10^3-10^6 s to put constraints on the temporal evolution of the
flare properties and to identif... | astro-ph_HE |
On the Geometry of Curvature Radiation and Implications for Subpulse
Drifting: The phenomenon of subpulse drifting offers unique insights into the emission
geometry of pulsars, and is commonly interpreted in terms of a rotating
carousel of "spark" events near the stellar surface. We develop a detailed
geometric model... | astro-ph_HE |
Low Mass X-ray Binary Simulation Data Release: We present DABS (Database of Accreting Binary Simulations), an open-access
database of modelled Low Mass X-ray Binaries (LMXBs). DABS has been created
using evolutionary tracks of neutron star and black hole LMXBs, spanning a
large set of initial conditions for the accreto... | astro-ph_HE |
Electromagnetic Helicity in Classical Physics: This pedagogical note revisits the concept of electromagnetic helicity in
classical systems. In particular, magnetic helicity and its role in mean field
dynamo theories is briefly discussed highlighting the major mathematical
inconsistency in most of these theories---viola... | astro-ph_HE |
On the relation between hard X-ray photon index versus accretion rate
for super-Eddington accreting quasars: We investigate whether the hard X-ray photon index (${\Gamma}$) versus
accretion rate correlation for super-Eddington accreting quasars is different
from that for sub-Eddington accreting quasars. We construct ... | astro-ph_HE |
XMM-Newton and Swift Observations of the Seyfert 1 AGN NGC 5940: Probing the physics of the accretion flow around active galactic nuclei (AGN)
is crucial to understanding their emission mechanisms as well as being able to
constrain the geometrical and variability properties of the different regions
around them. The sof... | astro-ph_HE |
First observation of MeV gamma-ray universe with bijective imaging
spectroscopy using the Electron-Tracking Compton Telescope aboard SMILE-2+: MeV gamma-rays provide a unique window for the direct measurement of line
emissions from radioisotopes, but observations have made little significant
progress after COMPTEL/{\... | astro-ph_HE |
Feature Extraction on Synthetic Black Hole Images: The Event Horizon Telescope (EHT) recently released the first horizon-scale
images of the black hole in M87. Combined with other astronomical data, these
images constrain the mass and spin of the hole as well as the accretion rate
and magnetic flux trapped on the hole.... | astro-ph_HE |
The High Energy X-ray Probe (HEX-P): A New Window into Neutron Star
Accretion: Accreting neutron stars (NSs) represent a unique laboratory for probing the
physics of accretion in the presence of strong magnetic fields ($B\gtrsim 10^8$
G). Additionally, the matter inside the NS itself exists in an ultra-dense,
cold st... | astro-ph_HE |
Cooling of neutron stars and hybrid stars with a stiff hadronic EoS: Within the "nuclear medium cooling" scenario of neutron stars all reliably
known temperature - age data, including those of the central compact objects in
the supernova remnants of Cassiopeia A and XMMU-J1732, can be comfortably
explained by a set of ... | astro-ph_HE |
Delving Into X-ray Obscuration of Type 2 AGN, Near and Far: Using self-consistent, physically motivated models, we investigate the X-ray
obscuration in 19 Type 2 [OIII] 5007 \AA\ selected AGN, 9 of which are local
Seyfert 2 galaxies and 10 of which are Type 2 quasar candidates. We derive
reliable line-of-sight and glob... | astro-ph_HE |
Giant Primeval Magnetic Dipoles: Macroscopic magnetic dipoles are considered as cosmic dark matter. Permanent
magnetism in relativistic field structures can involve some form of
superconductivity, one example being current-carrying string loops (`springs')
with vanishing net tension. We derive the cross section for fre... | astro-ph_HE |
Penetration of cosmic rays into dense molecular clouds: role of diffuse
envelope: A flux of cosmic rays (CRs) propagating through a diffuse ionized gas can
excite MHD waves, thus generating magnetic disturbances. We propose a generic
model of CR penetration into molecular clouds through their diffuse envelopes,
and i... | astro-ph_HE |
Testing the millisecond pulsar scenario of the Galactic center gamma-ray
excess with very high energy gamma-rays: The recent analyses of the Fermi Large Area Telescope data show an extended
GeV $\gamma$-ray excess on top of the expected diffuse background in the
Galactic center region, which can be explained with ann... | astro-ph_HE |
Study of general relativistic magnetohydrodynamic accretion flow around
black holes: We present a novel approach to study the global structure of steady,
axisymmetric, advective, geometrically thin, magnetohydrodynamic (MHD)
accretion flow around black holes in full general relativity (GR). Considering
ideal MHD cond... | astro-ph_HE |
Supernovae Powered by Collapsar Accretion in Gamma-Ray Burst Sources: The association of long-duration gamma-ray bursts (LGRBs) with Type Ic
supernovae presents a challenge to supernova explosion models. In the collapsar
model for LGRBs, gamma rays are produced in an ultrarelativistic jet launching
from the magnetosphe... | astro-ph_HE |
Superbroad Component in Emission Lines of SS 433: We have detected new components in stationary emission lines of SS 433; these
are the superbroad components that are low-contrast substrates with a width of
2000--2500 km s-1 in He I $\lambda4922$ and H$\beta$ and 4000--5000 km s-1 in
He II $\lambda4686$. Based on 44 sp... | astro-ph_HE |
Statistics of X-ray flares of Sagittarius A*: evidence for solar-like
self-organized criticality phenomenon: X-ray flares have routinely been observed from the supermassive black hole,
Sagittarius A$^\star$ (Sgr A$^\star$), at our Galactic center. The nature of
these flares remains largely unclear, despite of many th... | astro-ph_HE |
Measuring the delay time distribution of binary neutron stars. II. Using
the redshift distribution from third-generation gravitational wave detectors
network: We investigate the ability of current and third-generation gravitational wave
(GW) detectors to determine the delay time distribution (DTD) of binary neutron... | astro-ph_HE |
On the origin of supergiant fast X-ray transients: A fraction of high-mass X-ray binaries are supergiant fast X-ray transients.
These systems have on average low X-ray luminosities, but display short flares
during which their X-ray luminosity rises by a few orders of magnitude. The
leading model for the physics governi... | astro-ph_HE |
Cosmological effects on the observed flux and fluence distributions of
gamma-ray bursts: Several claims have been put forward that an essential fraction of
long-duration BATSE gamma-ray bursts should lie at redshifts larger than 5.
This point-of-view follows from the natural assumption that fainter objects
should, on... | astro-ph_HE |
Deep Neural Networks for Estimation of Gamma-Ray Burst Redshifts: While the available set of Gamma-ray Burst (GRB) data with known redshift is
currently limited, a much larger set of GRB data without redshift is available
from different instruments. This data includes well-measured prompt gamma-ray
flux and spectral in... | astro-ph_HE |
Search for photon line-like signatures from Dark Matter annihilations
with H.E.S.S: Gamma-ray line signatures can be expected in the very-high-energy (VHE;
E_\gamma > 100 GeV) domain due to self-annihilation or decay of dark matter
(DM) particles in space. Such a signal would be readily distinguishable from
astrophys... | astro-ph_HE |
Evidence for two neutrinos bursts from SN1987A: The SN1987A in the Giant Magellanic Cloud was an amazing and extraordinary
event because it was detected in real time for different neutrinos experiments
($\nu$s) around the world. Approximate $\sim25$ events were observed in three
different experiments: Kamiokande II (KI... | astro-ph_HE |
Combined analyses of the antiproton production from cosmic-ray
interactions and its possible dark matter origin: Recent cosmic-ray (CR) studies have claimed the possibility of an excess on
the antiproton flux over the predicted models at around $10$ GeV, which can be
the signature of dark matter annihilating into had... | astro-ph_HE |
Testing astrophysical models for the PAMELA positron excess with cosmic
ray nuclei: The excess in the positron fraction reported by the PAMELA collaboration has
been interpreted as due to annihilation or decay of dark matter in the Galaxy.
More prosaically, it has been ascribed to direct production of positrons by
ne... | astro-ph_HE |
Construction of a Multidimensional Parallel Adaptive Mesh Refinement
Special Relativistic Hydrodynamics Code for Astrophysical Applications: We have developed a new computer code, RELDAFNA, to solve the conservative
equations of special relativistic hydrodynamics (SRHD) using adaptive mesh
refinement (AMR) on paralle... | astro-ph_HE |
Dwarf (Twin) Neutron Stars I: Did GW170817 Involve One?: Dwarf neutron stars are stable twins of neutron stars but with a maximum mass
less than that of neutron stars. Their existence brings into concordance the
seemingly conflicting information on the size of neutron stars inferred from
gravitational waves from GW1708... | astro-ph_HE |
Test of the superdiffusion model in the interstellar medium around the
Geminga pulsar: The TeV $\gamma$-ray halo around the Geminga pulsar is an important indicator
of cosmic-ray (CR) propagation in the local zone of the Galaxy as it reveals
the spatial distribution of the electrons and positrons escaping from the
pu... | astro-ph_HE |
On the triple pulsar profiles generated by ordinary mode: A detailed study of the refraction of an ordinary wave in the magnetosphere
of radio pulsars was carried out. For this, a consistent theory of the
generation of secondary particles was constructed, which essentially takes into
account the dependence of the numbe... | astro-ph_HE |
Are Superluminous Supernovae Powered By Collision Or By Millisecond
Magnetars?: Using our previously derived simple analytic expression for the bolometric
light curves of supernovae, we demonstrate that the collision of the fast
debris of ordinary supernova explosions with relatively slow-moving shells from
pre-super... | astro-ph_HE |
Dark Matter Annihilation in the Universe: The astronomical dark matter is an essential component of the Universe and
yet its nature is still unresolved. It could be made of neutral and massive
elementary particles which are their own antimatter partners. These dark matter
species undergo mutual annihilations whose effe... | astro-ph_HE |
Determining the Origin of Very-high-energy Gamma Rays from Galactic
Sources by Future Neutrino Observations: Recently, the Large High Altitude Air Shower Observatory (LHAASO) identified
12 $\gamma$-ray sources emitting gamma rays with energies above 100 TeV, making
them potential PeV cosmic-ray accelerators (PeVatron... | astro-ph_HE |
A multi-wavelength study of the gamma-ray binary candidate HESS
J1832-093: We investigate the nature of the unidentified very-high-energy (VHE)
gamma-ray object, HESS J1832-093, in a multi-wavelength context. Based on X-ray
variability and spectral index ($\Gamma_X\sim\,1.5$), and its broad-band
spectrum (which was r... | astro-ph_HE |
Jets, Disks and Winds from Spinning Black Holes: Nature or Nurture?: A brief summary is given of an alternative interpretation of the Event
Horizon Telescope observations of the massive black hole in the nucleus of the
nearby galaxy M87. It is proposed that the flow is primarily powered by the
black hole rotation, not ... | astro-ph_HE |
Detecting Kozai-Lidov imprints on the gravitational waves of
intermediate-mass black holes in galactic nuclei: A third object in the vicinity of a binary system causes variations in the
eccentricity and the inclination of the binary through the Kozai-Lidov effect.
We examine if such variations leave a detectable impr... | astro-ph_HE |
Model on pulsed GeV radiation from magnetars: We discuss a possible scenario for radiation mechanism of pulsed GeV
gamma-rays from magnetars. The magnetars have shown frequent X-ray bursts,
which would be triggered by crust fractures and could release the energy of
order of ~10^{41-42}erg. If the location of the crust ... | astro-ph_HE |
Cosmic Frontier Indirect Dark Matter Detection Working Group Summary: As part of the Snowmass process, the Cosmic Frontier Indirect-Detection
subgroup (CF2) has drawn on input from the Cosmic Frontier and the broader
Particle Physics community to produce this document. The purposes of this
report are to identify opport... | astro-ph_HE |
Stripped-envelope core-collapse supernova $^{56}$Ni masses: Persistently
larger values than supernovae type II: The mass of synthesised radioactive material is an important power source for
all supernova (SN) types. Anderson 2019 recently compiled literature values and
obtained $^{56}$Ni distributions for different c... | astro-ph_HE |
GRB jet structure and the jet break: We investigate the shape of the jet break in within-beam gamma-ray burst
(GRB) optical afterglows for various lateral jet structure profiles. We
consider cases with and without lateral spreading and a range of inclinations
within the jet core half-opening angle, $\theta_c$. We fit m... | astro-ph_HE |
A 350-MHz Green Bank Telescope Survey of Unassociated Fermi LAT Sources:
Discovery and Timing of Ten Millisecond Pulsars: We have searched for radio pulsations towards 49 Fermi Large Area Telescope
(LAT) 1FGL Catalog $\gamma$-ray sources using the Green Bank Telescope at 350
MHz. We detected 18 millisecond pulsars (M... | astro-ph_HE |
High-energy emission of variable objects in the OMC--VAR catalogue: OMC-VAR is the first catalogue of variable sources observed by the Optical
Monitoring Camera (OMC) on board INTEGRAL. It includes photometry and
variability data for more than 5000 sources of very different nature. In order
to study the multi-wavelengt... | astro-ph_HE |
Evidence for Astrophysical Muon Neutrinos from the Northern Sky with
IceCube: Results from the IceCube Neutrino Observatory have recently provided
compelling evidence for the existence of a high energy astrophysical neutrino
flux utilizing a dominantly Southern Hemisphere dataset consisting primarily of
nu_e and nu_t... | astro-ph_HE |
Absolute timing of the Crab pulsar with the INTEGRAL/SPI telescope: We have investigated the pulse shape evolution of the Crab pulsar emission in
the hard X-ray domain of the electromagnetic spectrum. In particular, we have
studied the alignment of the Crab pulsar phase profiles measured in the hard
X-rays and in other... | astro-ph_HE |
The spin of the black hole GRS 1716-249 determined from the hard
intermediate state: We present three simultaneous/quasi-simultaneous NuSTAR and Swift datasets of
the black hole GRS 1716-249 in its hard intermediate state. The accretion disk
in this state may have reached the innermost stable circular orbit, and the
... | astro-ph_HE |
Uncovering Red and Dusty Ultraluminous X-ray Sources with Spitzer: We 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 par... | astro-ph_HE |
Gamma-Ray Burst Central Engines: Black Hole Vs. Magnetar: Discovered over forty years ago, Gamma-Ray Bursts (GRBs) remain a forefront
topic in modern astrophysics. Perhaps the most fundamental question associated
with GRBs is the nature of the astrophysical agent (or agents) that ultimately
powers them: the central eng... | astro-ph_HE |
The fast radio burst population evolves, consistent with the
star-formation rate: Fast radio bursts (FRBs) are extremely powerful sources of radio waves
observed at cosmological distances. We use a sophisticated model of FRB
observations -- presented in detail in a companion paper -- to fit FRB
population parameters ... | astro-ph_HE |
Anomalous bremsstrahlung and the structure of cosmic ray
electron-positron fluxes at the GeV-TeV energy range: We reveal that the energy spectra of electrons-positrons in primary cosmic
rays measured at atmosphere top have double structures: an excess component
$\Phi^s_{e^+}(E)=\Phi^s_{e^-}(E)$ around $400 GeV$, whic... | astro-ph_HE |
Magnetic field reversal in the turbulent environment around a repeating
fast radio burst: Fast radio bursts (FRBs) are brief, intense flashes of radio waves from
unidentified extragalactic sources. Polarized FRBs originate in highly
magnetized environments. We report observations of the repeating FRB 20190520B
spanni... | astro-ph_HE |
Non-linear diffusive shock acceleration: A recipe for injection of
electrons: Prescriptions for electron injection into the diffusive shock acceleration
process are required in many practical considerations of cosmic-ray
astrophysics, particularly in modeling of the synchrotron emission of
astrophysical sources. In p... | astro-ph_HE |
3D simulations of microquasar jets in clumpy stellar winds: High-mass microquasars consist of a massive star and a compact object, the
latter producing jets that will interact with the stellar wind. The evolution
of the jets, and ultimately their radiative outcome, could depend strongly on
the inhomogeneity of the wind... | astro-ph_HE |
XMM-Newton and Chandra observations of the unidentified Fermi-LAT source
3FGL J1016.5-6034: A Young Pulsar with a Nebula?: We report the discovery of a bright X-ray source in the XMM-Newton and
Chandra X-ray Observatory (CXO) images of the unidentified Fermi-LAT source
3FGL J1016.5-6034. The XMM-Newton spectrum of th... | astro-ph_HE |
Have Cherenkov telescopes detected a new light boson?: Recent observations by H.E.S.S. and MAGIC strongly suggest that the Universe
is more transparent to very-high-energy gamma rays than previously thought. We
show that this fact can be reconciled with standard blazar emission models
provided that photon oscillations ... | astro-ph_HE |
Nonparametric Representation of Neutron Star Equation of State Using
Variational Autoencoder: We introduce a new nonparametric representation of the neutron star (NS)
equation of state (EoS) by using the variational autoencoder (VAE). As a deep
neural network, the VAE is frequently used for dimensionality reduction s... | astro-ph_HE |
Brightest Fermi-LAT Flares of PKS 1222+216: Implications on Emission and
Acceleration Processes: We present a high time resolution study of the two brightest $\gamma$-ray
outbursts from a blazar PKS 1222+216 observed by the \textit{Fermi} Large Area
Telescope (LAT) in 2010. The $\gamma$-ray light-curves obtained in f... | astro-ph_HE |
Mechanism of Outflows in Accretion System: Advective Cooling Cannot
Balance Viscous Heating?: Based on no-outflow assumption, we investigate steady state, axisymmetric,
optically thin accretion flows in spherical coordinates. By comparing the
vertically integrated advective cooling rate with the viscous heating rate,... | astro-ph_HE |
Multi-wavelength temporal and spectral study of PKS 0402-362: We study the long-term behavior of the bright gamma-ray blazar PKS 0402-362.
Over a span of approximately 12.5 years, from August 2008 to January 2021, we
gathered Fermi-LAT temporal data and identified three distinct periods of
intense $\gamma$-ray activity... | astro-ph_HE |
Search for correlations between the arrival directions of IceCube
neutrino events and ultrahigh-energy cosmic rays detected by the Pierre Auger
Observatory and the Telescope Array: This paper presents the results of different searches for correlations
between very high-energy neutrino candidates detected by IceCube... | astro-ph_HE |
A Deep Observation of Gamma-ray Emission from Cassiopeia A using VERITAS: Supernova remnants (SNRs) have long been considered the leading candidates
for the accelerators of cosmic rays within the Galaxy through the process of
diffusive shock acceleration. The connection between SNRs and cosmic rays is
supported by the ... | astro-ph_HE |
Gamma-ray Observation of the Cygnus Region in the 100 TeV Energy Region: We report observations of gamma-ray emissions with energies in the 100 TeV
energy region from the Cygnus region in our Galaxy. Two sources are
significantly detected in the directions of the Cygnus OB1 and OB2
associations. Based on their position... | astro-ph_HE |
Dead zone in the polar-cap accelerator of pulsars: We study plasma flows above pulsar polar caps using time-dependent
simulations of plasma particles in the self-consistent electric field. The flow
behavior is controlled by the dimensionless parameter alpha=(j/c rho_GJ) where
j is the electric current density and rho_G... | astro-ph_HE |
Towards an Understanding of Changing-Look Quasars: An Archival
Spectroscopic Search in SDSS: The uncertain origin of the recently-discovered `changing-looking' quasar
phenomenon -- in which a luminous quasar dims significantly to a quiescent
state in repeat spectroscopy over ~10 year timescales -- may present unexpec... | astro-ph_HE |
Linear Analysis of Fast-Pairwise Collective Neutrino Oscillations in
Core-Collapse Supernovae based on the Results of Boltzmann Simulations: Neutrinos are densely populated deep inside the core of massive stars after
their gravitational collapse to produce supernova explosions and form compact
stars such as neutron s... | astro-ph_HE |
Constraining the size of the Comptonizing medium by modeling the energy
dependent time-lags of kHz QPOs of Neutron star system: In earlier works, we had shown that the observed soft lags and r.m.s versus
energy of the lower kHz QPO of neutron star binaries can be explained in the
framework of a thermal Comptonization... | astro-ph_HE |
Chasing candidate Supergiant Fast X-ray Transients in the 1,000 orbits
INTEGRAL/IBIS catalog: We report results from an investigation at hard X-rays (above 18 keV) and
soft X-rays (below 10 keV) of a sample of X-ray transients located on the
Galactic plane and detected with the bursticity method, as reported in the
l... | astro-ph_HE |
Infrared study of H1743-322 in outburst: a radio-quiet and NIR-dim
microquasar: The X-ray binary, black hole candidate, and microquasar H1743-322 exhibited a
series of X-ray outbursts between 2003 and 2008. We took optical/infrared (OIR)
observations with the ESO/NTT telescope during 3 of these outbursts (2003,
2004,... | astro-ph_HE |
Simulations of coalescing black holes: We describe the methods and results of numerical simulations of coalescing
black holes. The simulation in dynamical spacetime covers the inspiral, merger,
and ringdown phases. We analyze the emission of gravitational waves and
properties of a black hole being the merger product. W... | astro-ph_HE |
Massive BH Binaries as Periodically-Variable AGN: Massive black-hole (MBH) binaries, which are expected to form following the
merger of their parent galaxies, produce gravitational waves which will be
detectable by Pulsar Timing Arrays at nanohertz frequencies (year periods).
While no confirmed, compact MBH binary syst... | astro-ph_HE |
Evolution of Accretion Disc Geometry of GRS~1915+105 during its $χ$
state as revealed by TCAF solution: The evolution of the C-type low frequency quasi-periodic oscillations
(LFQPOs) and associated time lag in transient black hole sources as a function
of time can be explained by variation of the Compton cloud size i... | astro-ph_HE |
Potential for Precision Measurement of Low-Energy Antiprotons with GAPS
for Dark Matter and Primordial Black Hole Physics: The general antiparticle spectrometer (GAPS) experiment is a proposed
indirect dark matter search focusing on antiparticles produced by WIMP (weakly
interacting massive particle) annihilation and... | astro-ph_HE |
Effects of nuclear matter and composition in core-collapse supernovae
and long-term proto-neutron star cooling: We study the influence of hot and dense matter in core-collapse supernovae by
adopting up-to-date nuclear equation of state (EOS) based on the microscopic
nuclear many-body frameworks. We explore effects of... | astro-ph_HE |
Phase-Resolved Spectroscopy of the Low-Mass X-ray Binary V801 Ara: We present phase-resolved optical spectra of the low mass X-ray binary system
V801 Ara. The spectra, obtained in 2014 with IMACS on the Magellan/Baade
telescope at Las Campanas Observatory, cover the full binary orbit of 3.8
hours. They contain strong e... | astro-ph_HE |
Pulse Profile Modeling of Thermonuclear Burst Oscillations I: The Effect
of Neglecting Variability: We study the effects of the time-variable properties of thermonuclear X-ray
bursts on modeling their millisecond-period burst oscillations. We apply the
pulse profile modeling technique that is being used in the analys... | astro-ph_HE |
A low-mass binary neutron star: long-term ejecta evolution and kilonovae
with weak blue emission: We study the long-term evolution of ejecta formed in a binary neutron star
(BNS) merger that results in a long-lived remnant NS by performing a
hydrodynamics simulation with the outflow data of a numerical relativity
sim... | astro-ph_HE |
A VLA search for 5 GHz radio transients and variables at low Galactic
latitudes: We present the results of a 5 GHz survey with the Very Large Array, designed
to search for short-lived (<1 day) transients and to characterize the
variability of radio sources at milli-Jansky levels. A total sky area of 2.66
deg^2, sprea... | astro-ph_HE |
Dependence of inner accretion disk stress on parameters: the
Schwarzschild case: We explore the parameter dependence of inner disk stress in black hole
accretion by contrasting the results of a number of simulations, all employing
3-d general relativistic MHD in a Schwarzschild spacetime. Five of these
simulations we... | astro-ph_HE |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.