text stringlengths 73 2.82k | category stringclasses 21
values |
|---|---|
Search for Outbursts in the Narrow 511-keV Line from Compact Sources
Based on INTEGRAL Data: We present the results of a systematic search for outbursts in the narrow
positron annihilation line on various time scales (5x10^4 - 10^6 s) based on
the SPI/INTEGRAL data obtained from 2003 to 2008. We show that no outburst... | astro-ph |
Testing the Frozen-Flow Approximation: We investigate the accuracy of the frozen--flow approximation (FFA), recently
proposed by Matarrese \etal (1992), for following the nonlinear evolution of
cosmological density fluctuations under gravitational instability. We compare a
number of statistics between results of the FF... | astro-ph |
Full Monte Carlo simulations of radio emission from extensive air
showers with CoREAS: CoREAS is a Monte Carlo simulation code for the calculation of radio emission
from extensive air showers. It is based on the "endpoint formalism" for
radiation from moving charges implemented directly in CORSIKA. Consequently,
the ... | astro-ph |
Rest-frame UV single-epoch black hole mass estimates of low-luminosity
AGN at intermediate redshifts: The ability to accurately derive black hole (BH) masses at progressively
higher redshifts and over a wide range of continuum luminosities has become
indispensable in the era of large-area extragalactic spectroscopic ... | astro-ph |
Detrending algorithms in large time-series: Application to TFRM-PSES
data: Certain instrumental effects and data reduction anomalies introduce
systematic errors in photometric time-series. Detrending algorithms such as the
Trend Filtering Algorithm (TFA) (Kov\'{a}cs et al. 2004) have played a key role
in minimizing t... | astro-ph |
Proper Motions of H2O Masers in the Water Fountain Source IRAS
19190+1102: We report on the results of two epochs of Very Long Baseline Array (VLBA)
observations of the 22 GHz water masers toward IRAS 19190+1102. The water maser
emission from this object shows two main arc-shaped formations perpendicular to
their NE-... | astro-ph |
Radio Relics in Clusters of Galaxies: In this paper we review the observational results on Relic radio sources in
clusters of galaxies. We discuss their observational properties, structures and
radio spectra. We will show that Relics can be divided according to their size,
morphology, and location in the galaxy cluster... | astro-ph |
Energy balance and Alfvén Mach numbers in compressible
magnetohydrodynamic turbulence with a large-scale magnetic field: Energy equipartition is a powerful theoretical tool for understanding
astrophysical plasmas. It is invoked, for example, to measure magnetic fields
in the interstellar medium (ISM), as evidence for... | astro-ph |
Radio Emission from UV Cet: Auroral Emission from a Stellar
Magnetosphere: The archetypical flare star UV Cet was observed by MeerKAT on 5-6 October
2021. A large radio outburst with a duration of $\sim\!2$ hr was observed
between 886-1682 MHz with a time resolution of 8s and a frequency resolution of
0.84 MHz, enabl... | astro-ph |
A multidimensional hydrodynamic code for structure evolution in
cosmology: A cosmological multidimensional hydrodynamic code is described and tested.
This code is based on modern high-resolution shock-capturing techniques. It can
make use of a linear or a parabolic cell reconstruction as well as an
approximate Rieman... | astro-ph |
Statistical Analysis of Soft X-Ray Solar Flares During Solar Cycles 21,
22 and 23: This paper presents a statistical analysis of Soft X-ray (SXR) flares during
the period January 1976 to December 2007 covering solar cycles (SCs) 21, 22,
and 23. We have analysed north-south (N-S) and east-west (E-W) asymmetry of SXR
a... | astro-ph |
Search for sub-millimeter H2O masers in active galaxies - the detection
of a 321 GHz H2O maser in NGC4945: We present further results of a search for extragalactic submillimeter H2O
masers using the Atacama Large Millimeter/Submillimeter Array (ALMA). The
detection of a 321 GHz H2O maser in the nearby Type 2 Seyfert ... | astro-ph |
The effects of relativistic bulk motion of X-ray flares in the corona on
the iron Kalpha line in Seyfert 1 galaxies: We study the effects of the bulk motion of X-ray flares on the shape and
equivalent width of the iron Kalpha line from an untruncated cold disk around a
Kerr black hole using fully relativistic calcula... | astro-ph |
Statistical properties of flares and sunspots over the solar cycle: The present paper reviews results derived from statistical studies on solar
activity indices. The prolonged minimum phase of cycle 23 raised the question
of peculiarities inherent in cycle 23. The most important solar activity index
is the relative sun... | astro-ph |
Radiative and dynamic stability of a dilute plasma: We analyze the linear stability of a dilute, hot plasma, taking into account
the effects of stratification and anisotropic thermal conduction. The work is
motivated by attempts to understand the dynamics of the intracluster medium in
galaxy clusters. We show that magn... | astro-ph |
Intrinsic Instrumental Polarization and High-Precision Pulsar Timing: Radio telescopes are used to accurately measure the time of arrival (ToA) of
radio pulses in pulsar timing experiments that target mostly millisecond
pulsars (MSPs) due to their high rotational stability. This allows for detailed
study of MSPs and fo... | astro-ph |
WIMP decay as a possible Warm Dark Matter model: The Weakly Interacting Massive Particles(WIMPs) have long been the favored
CDM candidate in the standard $\Lambda$CDM model. However, owing to great
improvement in the experimental sensitivity in the past decade, some parameter
space of the SUSY-based WIMP model is ruled... | astro-ph |
WMAP2006: Cosmological Parameters and Large-scale Structure of the
Universe: The parameters of cosmological model with cold dark matter and cosmological
constant (Lambda CDM) have been determined on a basis of three-year cosmic
microwave background observations by space mission WMAP, as well as the data on
the large-... | astro-ph |
Numerical and analytical studies on model gravitating systems: In this thesis we study the evolution of systems of concentric shells
interacting gravitationally and in the process (1) propose and implement a
nearly energy-conserving numerical integration scheme for evolving the
concentric spherical shells systems with ... | astro-ph |
Spectral Survey of X-Ray Bright Active Galactic Nuclei from the Rossi
X-ray Timing Explorer: Using long-term monitoring data from the Rossi X-ray Timing Explorer (RXTE),
we have selected 23 active galactic nuclei (AGN) with sufficient brightness and
overall observation time to derive broadband X-ray spectra from 3 to... | astro-ph |
The Temporal Analysis of Light Pollution in Turkey using VIIRS data: Artificial Light pollution (AL) in Turkey and in Turkish observatories
between 2012--2020 have been studied using the archival data of Visible
Infrared Imaging Radiometer Suite (VIIRS) instrument. The astroGIS database has
been used in processing the ... | astro-ph |
The Imprint of Presupernova Winds on Supernova Remnant Evolution:
Towards More Realistic Models for Type Ia Supernova Remnants and their
Spectra: Supernova remnants are usually analysed in the light of hydrodynamical models
of the interaction of supernova ejecta with either a constant density ambient
medium or a ci... | astro-ph |
Formation of the Musca filament: Evidence for asymmetries in the
accretion flow due to a cloud-cloud collision: Context. Dense molecular filaments are ubiquituous in the interstellar
medium, yet their internal physical conditions and formation mechanism remain
debated. Aims. We study the kinematics and physical condi... | astro-ph |
Joint analysis of EDGES $21$-cm line observations with standard candles
and rulers in $Λ$CDM and non-adiabatic gCg models: A decomposed generalised Chaplygin gas (gCg) with energy flux from dark
energy to dark matter, represented by a negative value for the gas parameter
$\alpha$, is shown to alleviate the tension be... | astro-ph |
Bisymmetric normal modes in soft-centred and realistic galactic discs: We test methods for the determination of unstable modes in stellar discs: a
point collocation scheme in the action sub-space, a scheme based on expansion
of the density and potential on the biorthonormal basis, and a finite element
method. Using mod... | astro-ph |
Cosmology with Modified Newtonian Dynamics (MOND): It is well-known that the application of Newtonian dynamics to an expanding
spherical region leads to the correct relativistic expression (the Friedmann
equation) for the evolution of the cosmic scale factor. Here, the cosmological
implications of Milgrom's modified Ne... | astro-ph |
Multi-wavelength observation of cosmic-ray air-showers with
CODALEMA/EXTASIS: Since 2003, significant efforts have been devoted to the understanding of the
radio emission of extensive air shower in the range [20-200] MHz. Despite some
studies led until the early nineties, the [1-10] MHz band has remained unused
for 2... | astro-ph |
Origin of the long-term modulation of radio emission of LS I +61 303: One of the most unusual aspects of the X-ray binary LSI +61 303 is that at
each orbit (P1=26.4960 \pm 0.0028 d) one radio outburst occurs whose amplitude
is modulated with Plong, a long-term period of more than 4 yr. It is still not
clear whether the... | astro-ph |
Fossil Signatures of Main-sequence Convective Core Overshoot Estimated
through Asteroseismic Analyses: Some physical processes that occur during a star's main-sequence evolution
also affect its post main-sequence evolution. It is well known that stars with
masses above approximately 1.1 $M_{\odot}$ have well-mixed co... | astro-ph |
Generation of High-Energy Photons at Ultra-Relativistic Shock Breakout
in Supernovae: We present theoretical expectations for non-thermal emission due to the bulk
Comptonization at the ultra-relativistic shock breakout. We calculate the
transfer of photons emitted from the shocked matter with a Monte Carlo code
fully... | astro-ph |
A new class of pulsating hot subdwarfs: Using high-cadence observations from the Zwicky Transient Facility at low
Galactic latitudes, we have discovered a new class of pulsating, hot, compact
stars. We have found four candidates, exhibiting blue colors ($g-r\leq-0.1$
mag), pulsation amplitudes of $>5\%$, and pulsation ... | astro-ph |
Understanding Radio-Selected Thermal Sources in M 33: Ultraviolet,
Optical, Near-Infrared, Spitzer Mid-Infrared, and Radio Observations: We present ultraviolet, optical, near-infrared, Spitzer mid-infrared, and
radio images of 14 radio-selected objects in M 33. These objects are thought to
represent the youngest phas... | astro-ph |
A star disrupted by a stellar black hole as the origin of the cloud
falling toward the Galactic center: We propose that the cloud moving on a highly eccentric orbit near the central
black hole in our Galaxy, reported by Gillessen et al., is formed by a
photoevaporation wind originating in a disk around a star that is... | astro-ph |
Coronal Polarization: We present an overview of the physical mechanisms responsible for the coronal
polarization at different wavelength regimes. We also review different
techniques using coronal polarization to determine various quantities necessary
for understanding the thermodynamic properties of the solar coronal p... | astro-ph |
Improving convergence in smoothed particle hydrodynamics simulations
without pairing instability: The numerical convergence of smoothed particle hydrodynamics (SPH) can be
severely restricted by random force errors induced by particle disorder,
especially in shear flows, which are ubiquitous in astrophysics. The incr... | astro-ph |
Large Inverse Transient Phase Response of Titanium-nitride-based
Microwave Kinetic Inductance Detectors: Following optical pulses ($\lambda=405~\text{nm}$) on titanium nitride (TiN)
Microwave Kinetic Inductance Detectors (MKIDs) cooled down at temperatures $T
\le T_c / 20$ ($T_c \simeq 4.6~\text{K}$), we observe a la... | astro-ph |
Hydrodynamics of Embedded Planets' First Atmospheres. I. A Centrifugal
Growth Barrier for 2D Flows: In the core accretion paradigm of planet formation, gas giants only form a
massive atmosphere after their progenitors exceeded a threshold mass: the
critical core mass. Most (exo)planets, being smaller and rock/ice-dom... | astro-ph |
Stellar collisions in galactic centers: black hole growth and color
gradients: We study the effects of stellar collisions, particularly on feeding massive
black holes (BHs) and color gradients, in realistic galactic centers. We find
that the mass released by stellar collisions is not sufficient to account for
the pre... | astro-ph |
Decaying dark matter search with NuSTAR deep sky observations: We present the results of the search for decaying dark matter with particle
mass in the 6-40 keV range with NuSTAR deep observations of COSMOS and ECDFS
empty sky fields. We show that main contribution to the decaying dark matter
signal from the Milky Way g... | astro-ph |
HST Imaging in the Chandra Deep Field South: I. Multiple AGN Populations: We present preliminary results from imaging three HST/WFPC2 fields in V and I
within the Chandra Deep Field South (CDFS). HST's sensitivity and resolution
are sufficient to reveal optical counterparts for 24 of the 26 CDFS X-ray
sources detected ... | astro-ph |
Modelling extragalactic extinction through gamma-ray burst afterglows: We analyze extragalactic extinction profiles derived through gamma-ray burst
afterglows, using a dust model specifically constructed on the assumption that
dust grains are not immutable but respond time-dependently to the local
physics. Such a model... | astro-ph |
Likelihood Methods for the Detection and Characterization of Gamma-ray
Pulsars with the Fermi Large Area Telescope: The sensitivity of the Large Area Telescope (LAT) aboard the Fermi Gamma-ray
Space Telescope allows detection of thousands of new gamma-ray sources and
detailed characterization of the spectra and varia... | astro-ph |
Astroinformatics based search for globular clusters in the Fornax Deep
Survey: In the last years, Astroinformatics has become a well defined paradigm for
many fields of Astronomy. In this work we demonstrate the potential of a
multidisciplinary approach to identify globular clusters (GCs) in the Fornax
cluster of gal... | astro-ph |
Significance for signal changes in gamma-ray astronomy: We describe a straightforward modification of frequently invoked methods for
the determination of the statistical significance of a gamma-ray signal
observed in a counting process. A simple criterion is proposed to decide
whether a set of measurements of the numbe... | astro-ph |
Evidence of residual Doppler shift on three pulsars, PSR B1259-63,
4U1627-67 and PSR J2051-0827: The huge derivative of orbital period observed in binary pulsar PSR B1259-63,
the torque reversal displaying on low mass X-ray binary, 4U1627-67 and the long
term change of orbital period of PSR J2051-0827, seem totally u... | astro-ph |
The small observed scale of AGN--driven outflows, and inside--out disc
quenching: Observations of massive outflows with detectable central AGN typically find
them within radii $\lesssim 10$ kpc. We show that this apparent size
restriction is a natural result of AGN driving if this process injects total
energy only of... | astro-ph |
The state of globular clusters at birth II: primordial binaries: (abridged) In this paper, we constrain the properties of primordial binary
populations in Galactic globular clusters using the MOCCA Monte Carlo code for
cluster evolution. Our results are compared to the observations of Milone et
al. (2012) using the pho... | astro-ph |
Kinematic evolution of the young local associations and the Sco-Cen
complex: In this work we propose a scenario for the history of the recent star
formation (during the last 20-30 Myr) in the nearest solar neighbourhood (~150
pc), from the study of the spatial and kinematic properties of the members of
the so-called ... | astro-ph |
Science Highlights from VERITAS: The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is a
ground-based array located at the Fred Lawrence Whipple Observatory in southern
Arizona and is one of the world's most sensitive gamma-ray instruments at
energies of 85 GeV to $>$30 TeV. VERITAS has a wide scient... | astro-ph |
CMB Polarization can constrain cosmology better than CMB temperature: We demonstrate that for a cosmic variance limited experiment, CMB E
polarization alone places stronger constraints on cosmological parameters than
CMB temperature. For example, we show that EE can constrain parameters better
than TT by up to a factor... | astro-ph |
Intra Cluster Light properties in the CLASH-VLT cluster MACS
J1206.2-0847: We aim at constraining the assembly history of clusters by studying the intra
cluster light (ICL) properties, estimating its contribution to the fraction of
baryons in stars, f*, and understanding possible systematics/bias using
different ICL ... | astro-ph |
Planetary Nebulae in the Magellanic Clouds: Probing Stellar Evolution
and Populations: This review contains: (1) the scientific motivations for studying Planetary
Nebulae in the Magellanic Clouds; (2) a review of this field of study, from the
origins to the most recent results, focusing on the papers that have been
p... | astro-ph |
Constraints on Helium Enhancement in the Globular Cluster M3 (NGC 5272):
The Horizontal Branch Test: It has recently been suggested that the presence of multiple populations
showing various amounts of helium enhancement is the rule, rather than the
exception, among globular star clusters. An important prediction of t... | astro-ph |
Is there a polarization horizon?: Modern radio spectrometers make measurement of polarized intensity as a
function of Faraday depth possible. I investigate the effect of depolarization
along a model line of sight. I model sightlines with two components informed by
observations: a diffuse interstellar medium with a logn... | astro-ph |
Asteroseismic modeling of gravity modes in slowly rotating A/F stars
with radiative levitation: It has been known for several decades that transport of chemical elements is
induced by the process of microscopic atomic diffusion. Yet, the effect of
atomic diffusion, including radiative levitation, has hardly been stud... | astro-ph |
The Mexican Million Models Database: a virtual observatory for gaseous
nebulae: The 3MdB (Mexican Million Models database) is a large database of
photoionization models for H II regions. The number of free parameters for the
models is close to 15, including the description of the ionizing Spectral
Energy Distribution... | astro-ph |
Probing the magnetosphere of the M8.5 dwarf TVLM513-46546 by modelling
its auroral radio emission. Hint of star exoplanet interaction?: In this paper we simulate the cyclic circularly-polarised pulses of the
ultra-cool dwarf TVLM513-46546, observed with the VLA at 4.88 and 8.44 GHz on
May 2006, by using a 3D model of... | astro-ph |
Magnetic flux emergence in fast rotating stars: Fast rotating cool stars are characterised by high magnetic activity levels
and frequently show dark spots up to polar latitudes. Their distinctive surface
distributions of magnetic flux are investigated in the context of the
solar-stellar connection by applying the solar... | astro-ph |
Gemini Near-Infrared Field Spectrograph Observations of the Seyfert 2
Galaxy Mrk 3: Feeding and Feedback on Galactic and Nuclear Scales: We explore the kinematics of the stars, ionized gas, and warm molecular gas
in the Seyfert 2 galaxy Mrk~3 (UGC~3426) on nuclear and galactic scales with
{\it Gemini} Near-Infrared F... | astro-ph |
Inverse Compton cooling in Klein-Nishina regime and GRB prompt spectrum: Synchrotron radiation mechanism, when electrons are accelerated in a
relativistic shock, is known to have serious problems to explain the observed
gamma-ray spectrum below the peak for most Gamma-Ray Bursts (GRBs); the
synchrotron spectrum below t... | astro-ph |
Photometric Study on Stellar Magnetic Activity: I. Flare Variability of
Red Dwarf Stars in the Open Cluster M37: Based on one-month long MMT time-series observations of the open cluster M37,
we monitored light variations of nearly 2500 red dwarfs and successfully
identified 420 flare events from 312 cluster M dwarf s... | astro-ph |
On the early chemical evolution of the Milky Way: A few topics concerning the early chemical evolution of the Milky Way are
critically discussed. In particular, it is argued that: 1) Observed abundance
patterns of extremely metal poor stars (of Pop. II) do not constrain the mass
range of the first generation (Pop. III)... | astro-ph |
Shedding Light on the Isolation of Luminous Blue Variables: In the standard view of massive star evolution, luminous blue variables
(LBVs) are transitional objects between the most massive O-type stars and
Wolf-Rayet (WR) stars. With short lifetimes, these stars should all be found
near one another. A recent study of L... | astro-ph |
Luminosity effect of O I 7771-5 triplet and atmospheric microturbulence
in evolved A-, F-, and G-type stars: It is known that the strength of neutral oxygen triplet lines at 7771-5 A
shows a luminosity effect in evolved A through G stars. However, its general
behavior across the HR diagram is not yet well understood,... | astro-ph |
HST/ACS color-magnitude diagrams of candidate intermediate-age M 31
globular clusters. The role of blue horizontal branches: We present deep (V ~ 28.0) BV photometry obtained with the wide field channel
of the Advanced Camera for Surveys on board HST for four M31 globular clusters
that were identified as candidate in... | astro-ph |
Dissipative dark matter explains rotation curves: Dissipative dark matter, where dark matter particles interact with a massless
(or very light) boson, is studied. Such dark matter can arise in simple hidden
sector gauge models, including those featuring an unbroken $U(1)'$ gauge
symmetry, leading to a dark photon. Prev... | astro-ph |
Investigating the Effects of Finite Resolution on Observed Transverse
Jet Profiles: Both the emission properties and evolution of Active Galactic Nuclei (AGN)
radio jets are dependent on the magnetic fields that thread them. Faraday
Rotation gradients are a very important way of investigating these magnetic
fields, a... | astro-ph |
The Bright Rim Prominences according to 2.5D Radiative Transfer: Solar prominences observed close to the limb commonly include a bright
feature that, from the perspective of the observer, runs along the interface
between itself and the underlying chromosphere. Despite several idealised
models being proposed to explain ... | astro-ph |
Methoxymethanol Formation Starting from CO-Hydrogenation: Methoxymethanol (CH3OCH2OH, MM) has been identified through gas-phase
signatures in both high- and low-mass star-forming regions. This molecule is
expected to form upon hydrogen addition and abstraction reactions in CO-rich
ice through radical recombination of C... | astro-ph |
Ram Pressure Stripping in the Low Luminosity Virgo Cluster Elliptical
Galaxy NGC 4476: We present a deep VLA search for HI emission from the low-luminosity Virgo
Cluster elliptical galaxy NGC 4476, which contains 1.1 x 10^8 M_sun of
molecular gas in an undisturbed disk in regular rotation. No HI was detected.
The rms... | astro-ph |
The Crab Pulsar at Centimeter Wavelengths II: Single Pulses: We have carried out new, high-frequency, high-time-resolution observations of
the Crab pulsar. Combining these with our previous data, we characterize bright
single pulses associated with the Main Pulse, both the Low-Frequency and
High-Frequency Interpulses, ... | astro-ph |
The Role for the Inner Disk in Mass Accretion to the Star in the Early
Phase of Star Formation: A physical mechanism that drives FU Orionis-type outbursts is reconsidered.
We study the effect of inner part of a circumstellar disk covering a region
from near the central star to the radius of approximately $5$ AU (here... | astro-ph |
Kinetic "jets" from fast moving pulsars: Some fast-moving pulsars, like the Guitar and the Lighthouse, exhibit
asymmetric non-thermal emission features that extend well beyond their ram
pressure confined pulsar wind nebulae (PWNe). Using 3D relativistic simulations
we explain these features as kinetically streaming pul... | astro-ph |
The Spitzer ice legacy: Ice evolution from cores to protostars: Ices regulate much of the chemistry during star formation and account for up
to 80% of the available oxygen and carbon. In this paper, we use the Spitzer
c2d ice survey, complimented with data sets on ices in cloud cores and
high-mass protostars, to determ... | astro-ph |
X-ray properties of early-type stars in the Tarantula Nebula from T-ReX: We reassess the historical $L_{X}/L_{Bol}$ relation for early-type stars from
a comparison between T-ReX, the Chandra ACIS X-ray survey of the Tarantula
Nebula in the LMC, and contemporary spectroscopic analysis of massive stars
obtained primarily... | astro-ph |
Extreme chemical abundance ratio suggesting an exotic origin for an
ultra-diffuse galaxy: Ultra diffuse galaxies are a population of extended galaxies but with
relatively low luminosities. The origin of these objects remains unclear,
largely due to the observational challenges of the low surface brightness
Universe. ... | astro-ph |
Discerning Exoplanet Migration Models Using Spin-Orbit Measurements: We investigate the current sample of exoplanet spin-orbit measurements to
determine whether a dominant planet migration channel can be identified, and at
what confidence. We use the predictions of Kozai migration plus tidal friction
(Fabrycky and Trem... | astro-ph |
Laboratory Observations and Simulations of Phase Reddening: The visible reflectance spectrum of many solar system bodies changes with
changing viewing geometry for reasons not fully understood. It is often
observed to redden (increasing spectral slope) with increasing solar phase
angle, an effect known as phase reddeni... | astro-ph |
The COS CGM Compendium. III: Metallicity and Physical Properties of the
Cool Circumgalactic Medium at z<1: We characterize the metallicities and physical properties of cool,
photoionized gas in a sample of 152 z<1 strong Lya forest systems (SLFSs,
absorbers with 15<log N(HI)<16.2). The sample is drawn from our COS
ci... | astro-ph |
Particle Acceleration in Relativistic Shearing Flows: Energy Spectrum: We consider the acceleration of charged particles in relativistic shearing
flows, with Lorentz factor up to $\Gamma_0 \sim 20$. We present numerical
solutions to the particle transport equation and compare these with results
from analytical calculat... | astro-ph |
Relativistic outflows from remnants of compact object mergers and their
viability for short gamma-ray bursts: We present the first general relativistic hydrodynamic models of the launch
and evolution of relativistic jets and winds, driven by thermal energy
deposition, possibly due to neutrino-antineutrino annihilatio... | astro-ph |
Distance measurements as a probe of cosmic acceleration: A major recent evelopment in observational cosmology has been an accurate
measurement of the luminosity distance-redshift relation out to redshifts z=0.8
from Type Ia supernova standard candles. The results have been argued as
evidence for cosmic acceleration. It... | astro-ph |
Light Nuclei solving Auger puzzles. The Cen-A imprint: Ultra High Energy Cosmic Rays (UHECR) map at 60 EeV have been found recently
by AUGER group spreading anisotropy signatures in the sky. The result have been
interpreted as a manifestation of AGN sources ejecting protons at GZK edges
mostly from Super-galactic Plane... | astro-ph |
Selecting Quasar Candidates by a SVM Classification System: We develop and demonstrate a classification system constituted by several
Support Vector Machines (SVM) classifiers, which can be applied to select
quasar candidates from large sky survey projects, such as SDSS, UKIDSS, GALEX.
How to construct this SVM classif... | astro-ph |
Broadband Observations of the Compton-thick Nucleus of NGC 3393: We present new NuSTAR and Chandra observations of NGC 3393, a galaxy reported
to host the smallest separation dual AGN resolved in the X-rays. While past
results suggested a 150 pc separation dual AGN, three times deeper Chandra
imaging, combined with ada... | astro-ph |
Estimation of the XUV radiation onto close planets and their evaporation: Context: The current distribution of planet mass vs. incident stellar X-ray
flux supports the idea that photoevaporation of the atmosphere may take place
in close-in planets. Integrated effects have to be accounted for. A proper
calculation of th... | astro-ph |
Twenty Years of Searching for (and Finding) Globular Cluster Pulsars: Globular clusters produce orders of magnitude more millisecond pulsars per
unit mass than the Galactic disk. Since the first cluster pulsar was uncovered
twenty years ago, at least 138 have been identified - most of which are binary
millisecond pulsa... | astro-ph |
Survey of Li-rich giants among Kepler and LAMOST fields: Determination
of Li-rich giants Evolutionary Phase: In this letter, we report the discovery of 24 new super Li-rich (A(Li) $\ge$
3.2) giants of He-core burning phase at red clump region. Results are based on
systematic search of a large sample of about 12,500 g... | astro-ph |
Planet formation via pebble accretion in externally photoevaporating
discs: We demonstrate that planet formation via pebble accretion is sensitive to
external photoevaporation of the outer disc. In pebble accretion, planets grow
by accreting from a flux of solids (pebbles) that radially drift inwards from
the pebble ... | astro-ph |
Galaxies behind the Milky Way and the Great Attractor: Dust and stars in the plane of the Milky Way create a "Zone of Avoidance" in
the extragalactic sky. Galaxies are distributed in gigantic labyrinth
formations, filaments and great walls with occasional dense clusters. They can
be traced all over the sky, except wher... | astro-ph |
Dark energy with rigid voids versus relativistic voids alone: The standard model of cosmology is dominated - at the present epoch - by dark
energy. Its voids are rigid and Newtonian within a relativistic background. The
model prevents them from becoming hyperbolic. Observations of rapid velocity
flows out of voids are ... | astro-ph |
Serendipitous discovery of a cluster of galaxies with a peculiar central
galaxy: We report the serendipitous discovery of a cluster of galaxies at z=0.369.
Thirty-eight candidate members were identified based on rough broad-band
photometric redshifts, and three members were confirmed spectroscopically. The
brightest ... | astro-ph |
A deterministic model for forecasting long-term solar activity: A phenomenological model is presented for the quantitative description of
individual solar cycles' features, such as onset, intensity, evolution, in
terms of the number of M and X-class solar flares. The main elements of the
model are the relative ecliptic... | astro-ph |
NGC 5128 globular cluster candidates out to 150 kpc: a comprehensive
catalog from Gaia and ground based data: We present a new catalog of 40502 globular cluster (GC) candidates in NGC
5128 out to a projected radius of $\sim$150 kpc, based on data from the
Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS), G... | astro-ph |
Probing Flavor Structure of Cosmic Ray $e^\mp$ Spectrum and Implications
for Dark Matter Indirect Searches: Measuring high energy cosmic ray electrons/positrons (CRE) provides important
means for the dark matter (DM) indirect detection and for probing the nearby
galactic sources. In this work, we perform a systematic... | astro-ph |
Constraining the equation of state of neutron stars using multimessenger
observations: Neutron stars are the densest objects known in our visible universe.
Properties of matter inside a neutron star are encoded in its equation of
state, which has wide-ranging uncertainty from a theoretical perspective. With
the curre... | astro-ph |
Timing calibration of the APOLLO experiment: The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) began
millimeter-precision ranging to the Moon in 2006. Until now, a comprehensive
validation of APOLLO system range accuracy has not been possible because of
centimeter-scale deficiencies in computational m... | astro-ph |
Mass measurements and 3D orbital geometry of PSR J1933$-$6211: PSR J1933$-$6211 is a 3.5-ms pulsar in a 12.8-d orbit with a white dwarf
(WD). Its high proper motion and low dispersion measure result in such
significant interstellar scintillation that high signal-to-noise detections
require long observing durations or f... | astro-ph |
Searching for Low-mass Population III Stars Disguised as White Dwarfs: It is uncertain whether or not low-mass Population III stars ever existed.
While limits on the number density of Population III stars with $M_{\ast}
\approx 0.8~M_{\odot}$ have been derived using Sloan Digital Sky Survey (SDSS)
data, little is known... | astro-ph |
Applicability of the linearly perturbed FRW metric and Newtonian
cosmology: It has been argued that the effect of cosmological structure formation on the
average expansion rate is negligible, because the linear approximation to the
metric remains applicable in the regime of non-linear density perturbations. We
discus... | astro-ph |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.