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following the procedure described in pol et al., we update the galactic double neutron star (dns) merger rate by including the new, highly eccentric dns system j0509+3801 (lynch et al.). this leads to a new galactic dns merger rate of $\mathcal{r}_{\rm mw} = 37^{+24}_{-11}$ myr$^{-1}$, where the errors represent 90% co... | an updated galactic double neutron star merger rate based on radio pulsar populations |
we report the phase-connected timing ephemeris, polarization pulse profiles, faraday rotation measurements, and rotating-vector-model (rvm) fitting results of 12 millisecond pulsars (msps) discovered with the five-hundred-meter aperture spherical radio telescope (fast) in the commensal radio astronomy fast survey (craf... | arecibo and fast timing follow-up of 12 millisecond pulsars discovered in commensal radio astronomy fast survey |
this proceeding summarizes the talk given at the opening of the uhecr 2022 conference in l'aquila on the whitepaper `ultra-high-energy cosmic rays: the intersection of the cosmic and energy frontiers' [astroparticle physics 149 (2023) 102819 - arxiv:2205.05845] that has been prepared for the snowmass survey in the usa.... | the snowmass uhecr white paper on ultra-high-energy cosmic rays |
discovering pulsars is a significant and meaningful research topic in the field of radio astronomy. with the advent of astronomical instruments, the volume and rate of data acquisition have grown exponentially. this development necessitates a focus on artificial intelligence (ai) technologies that can mine large astron... | pulsar candidate classification using generative adversary networks |
broadband receiver data need color corrections applying to correct for the different source spectra across their wide bandwidths. the full integration over a receiver bandpass may be computationally expensive and redundant when repeated many times. color corrections can be applied, however, using a simple quadratic fit... | fastcc: fast color corrections for broadband radio telescope data |
a new version of the optical characteristics of astrometric radio sources (ocars) catalog is presented. this compiled catalog includes radio sources observed in different vlbi programs and experiments that result in source position determination, their redshift, and photometry in the visible and near-infrared bands. a ... | a new version of the ocars catalog of optical characteristics of astrometric radio sources |
low-latency detections of gravitational waves (gws) from compact stellar binary coalescences are crucial to enable prompt follow-up observations to astrophysical transients by conventional telescopes, as demonstrated by the first joint gw and electromagnetic observations on july 17, 2017. searching over the gw paramete... | gpu-acceleration on a low-latency binary-coalescence gravitational wave search pipeline |
the bluebild algorithm is a new technique for image synthesis in radio astronomy which forms a least-squares estimate of the sky intensity function using the theory of sampling and interpolation operators. we present an hpc implementation of the bluebild algorithm for radio-interferometric imaging: bluebild imaging++ (... | bipp: an efficient hpc implementation of the bluebild algorithm for radio astronomy |
astronomers occasionally detect an object having unexpected shape, unexplainable photometry, or unprecedented spectra that are inconsistent with our contemporary knowledge of the universe. upon careful assessment, many of these anomalies are discarded as mere noise, contamination, or faulty analysis. but some anomalies... | astronomical anomalies: their role in the quest for extraterrestrial life |
context. the advent of the fermi gamma-ray space telescope with its superb sensitivity, energy range, and unprecedented capability to monitor the entire 4π sky within less than 2-3 h, introduced a new standard in time domain gamma-ray astronomy. among several breakthroughs, fermi has - for the first time - made it poss... | f-gamma: multi-frequency radio monitoring of fermi blazars. the 2.64 to 43 ghz effelsberg light curves from 2007-2015 |
in 2012 markarian 421 underwent the largest flare ever observed in this blazar at radio frequencies. in the present study, we start exploring this unique event and compare it to a less extreme event in 2013. we use 15 ghz radio data obtained with the owens valley radio observatory 40-m telescope, 95 ghz millimetre data... | a combined radio and gev γ-ray view of the 2012 and 2013 flares of mrk 421 |
we present a catalog of 47 wide-angle tailed radio galaxies (wats), the watcat, mainly built including a radio morphological classification; wats were selected by combining observations from the national radio astronomy observatory/very large array sky survey (nvss), the faint images of the radio sky at twenty-centimet... | watcat: a tale of wide-angle tailed radio galaxies |
the fundamental limits of the microwave noise performance of high electron-mobility transistors (hemts) are of scientific and practical interest for applications in radio astronomy and quantum computing. self-heating at cryogenic temperatures has been reported to be a limiting mechanism for the noise, but cryogenic coo... | self-heating of cryogenic high electron-mobility transistor amplifiers and the limits of microwave noise performance |
we have identified outflows and bubbles in the taurus molecular cloud based on the ∼100 deg2 five college radio astronomy observatory 12co(1-0) and 13co(1-0) maps and the spitzer young stellar object catalogs. in the main 44 deg2 area of taurus, we found 55 outflows, of which 31 were previously unknown. we also found 3... | outflows and bubbles in taurus: star-formation feedback sufficient to maintain turbulence |
faraday rotation measures (rms) have been used for many studies of cosmic magnetism, and in most cases having more rms is beneficial for those studies. this has lead to the development of rm surveys that have produced large catalogs, as well as meta-catalogs collecting rms from many different publications. however, it ... | rmtable2023 and polspectra2023: standards for reporting polarization and faraday rotation measurements of radio sources |
closure phases and closure amplitudes have proven critical to modern radio interferometry due to their insensitivity to the uncertain station gains. we present the first set of closure quantities constructed from parallel-hand and cross-hand visibilities that are insensitive to both station gains and to polarimetric le... | closure traces: novel calibration-insensitive quantities for radio astronomy |
the physics of core-collapse (cc) supernovae (sne) and how the explosions depend on progenitor properties are central questions in astronomy. for only a handful of sne, the progenitor star has been identified in pre-explosion images. supernova remnants (snrs), which are observed long after the original sn event, provid... | measurement of the core-collapse progenitor mass distribution of the small magellanic cloud |
determining the mechanism by which high-mass stars are formed is essential for our understanding of the energy budget and chemical evolution of galaxies. by using the new iram kids array 2 (nika2) camera on the institut de radio astronomie millimétrique (iram) 30-m telescope, we have conducted high-sensitivity and larg... | gaston: galactic star formation with nika2 - evidence for the mass growth of star-forming clumps |
the sampling strategy of the transiting exoplanet survey satellite (tess) makes tess light curves extremely valuable for investigating the high cadence optical variability of active galactic nuclei (agn). however, because the tess instrument was primarily designed for exoplanet science, the use of the satellite for oth... | the rapid optical variability of the nearby radio-loud agn pictor a: introducing the quaver pipeline for agn science with tess |
source finding is one of the most challenging tasks in upcoming radio continuum surveys with ska precursors, such as the evolutionary map of the universe (emu) survey of the australian ska pathfinder (askap) telescope. the resolution, sensitivity, and sky coverage of such surveys is unprecedented, requiring new feature... | astronomical source detection in radio continuum maps with deep neural networks |
we present the results on the physical properties of filaments and dense cores in ic 5146, as a part of the trao funs project. we carried out on-the-fly mapping observations using the taeduk radio astronomy observatory (trao) 14 m telescope covering about 1 square degree of the area of ic 5146 using various molecular l... | trao survey of the nearby filamentary molecular clouds, the universal nursery of stars (trao funs). ii. filaments and dense cores in ic 5146 |
sensitive radio instruments are optimized for observing faint astronomical sources, and usually need to attenuate the received signal when observing the sun. there are only a handful of flux density calibrators that can comfortably be observed with the same attenuation setup as the sun. additionally, for wide field-of-... | robust absolute solar flux density calibration for the murchison widefield array |
we present the detection of a secondary outflow associated with a class i source, ser-emb 15, in the serpens molecular cloud. we reveal two pairs of molecular outflows consisting of three lobes, that is, primary and secondary outflows, using atacama large millimeter/submillimeter array 12co and sio line observations at... | secondary outflow driven by the protostar ser-emb 15 in serpens |
the axion is well motivated in physics. it solves the strong charge conjugation-parity reversal problem c p in fundamental physics and the dark matter problem in astronomy. its interaction with the electromagnetic field has been expected but never detected experimentally. such particles may convert to radio waves in th... | identifying axion conversion in compact star magnetospheres with radio-wave polarization signatures |
recent advances in technology coupled with the progress of observational radio astronomy methods resulted in achieving a major milestone of astrophysics - a direct image of the shadow of a supermassive black hole, taken by the earth-based event horizon telescope (eht). the eht was able to achieve a resolution of ∼ 20 μ... | orbital configurations of spaceborne interferometers for studying photon rings of supermassive black holes |
the arrival of the square kilometer array (ska) will revitalize all aspects of very long baseline interferometry (vlbi) astronomy at lower frequencies. in the last decade, there have been huge strides toward routinely achieving high precision vlbi astrometry at frequencies dominated by tropospheric contributions, most ... | multiview high precision vlbi astrometry at low frequencies |
in this paper we propose a model in which the coalescence of primordial black hole (pbhs) binaries with equal mass m ∼1028 g can emit luminous gigahertz (ghz) radio transient, which may be candidate sources for the observed fast radio bursts (frbs), if at least one black hole holds an appropriate amount of net electric... | fast radio bursts from primordial black hole binaries coalescence |
coronal magnetic fields are well known to be one of the crucial parameters defining coronal physics and space weather. however, measuring the global coronal magnetic fields remains challenging. the polarization properties of coronal radio emissions are sensitive to coronal magnetic fields. while they can prove to be us... | tackling the unique challenges of low-frequency solar polarimetry with the square kilometre array low precursor: the algorithm |
spectral structures due to the instrument response is the current limiting factor for the experiments attempting to detect the redshifted 21 cm signal from the epoch of reionization (eor). recent advances in the delay spectrum methodology for measuring the redshifted 21 cm eor power spectrum brought new attention to th... | the hydrogen epoch of reionization array dish iii: measuring chromaticity of prototype element with reflectometry |
due to the demand for high-speed wireless communications, carrier frequencies have increased in the search for both available and wider bands. the millimeter-wave and terahertz bands (0.1-3 thz) are commonly believed to be impractical for all but short-range links due to severe attenuation by atmospheric water vapor. h... | terabit-per-second satellite links: a path toward ubiquitous terahertz communication |
we report on eight millisecond pulsars (msps) in binary systems discovered with the arecibo l-band feed array (palfa) pulsar survey. phase-coherent timing solutions derived from 2.5-5 yr of observations carried out at the arecibo and jodrell bank observatories are provided. psr j1921+1929 is a 2.65 ms pulsar in a 39.6 ... | eight millisecond pulsars discovered in the arecibo palfa survey |
we present a statistical analysis of polarized near-infrared light from sgr a*, the radio source associated with the supermassive black hole at the center of the milky way. the observations were carried out using the adaptive optics instrument naco at the vlt ut4 in the infrared ks-band from 2004 to 2012. several polar... | polarized light from sagittarius a* in the near-infrared ks-band |
the physical origin of radio emission in radio-quiet active galactic nuclei (rq agn) remains unclear, whether it is a downscaled version of the relativistic jets typical of radio-loud (rl) agn, or whether it originates from the accretion disc. the correlation between 5 ghz and x-ray luminosities of rq agn, which follow... | discovery of millimetre-wave excess emission in radio-quiet active galactic nuclei |
we report the discovery of sdss j0849+1114 as the first known triple type 2 seyfert nucleus. it represents three active black holes that are identified from new spatially resolved optical slit spectroscopy using the dual imaging spectrograph on the 3.5 m telescope at the apache point observatory. we also present new co... | a trio of massive black holes caught in the act of merging |
ultra-diffuse galaxies have generated significant interest due to their large optical extents and low optical surface brightnesses, which challenge galaxy formation models. here we present resolved synthesis observations of 12 h i-bearing ultra-diffuse galaxies (huds) from the karl g. jansky very large array, as well a... | vla imaging of h i-bearing ultra-diffuse galaxies from the alfalfa survey |
in the interval of 4-10 september 2017, the sun presented multiple solar flares from active region ar 2673. there were also coronal mass ejections that interacted with the earth's magnetosphere. this solar activity produced several space weather events. these events were observed with ground-based instruments of the me... | space weather events, hurricanes, and earthquakes in mexico in september 2017 |
gas and dust in star-forming galaxies at the peak epoch of galaxy assembly are presently the topic of intense study, but little is known about the interstellar medium (ism) of distant, passively evolving galaxies. we report on a deep 3 mm band search with the iram/plateau de bure interferometer for molecular (h2) gas i... | a direct constraint on the gas content of a massive, passively evolving elliptical galaxy at z = 1.43 |
ir-uv spectroscopy of a benzene discharge reveals larger pahs and intermediates showing that different gas-phase pah growth mechanisms can occur under the same conditions. the identifications are promising candidates for radio astronomy searches. infrared signatures of polycyclic aromatic hydrocarbons (pahs) are detect... | polycyclic aromatic hydrocarbon growth in a benzene discharge explored by ir-uv action spectroscopy |
recent developments in astronomical radio telescopes opened new opportunities in imaging and spectroscopy of solar radio bursts at subsecond timescales. imaging in narrow frequency bands has revealed temporal variations in the positions and source sizes that do not fit into the standard picture of type iii solar radio ... | subsecond time evolution of type iii solar radio burst sources at fundamental and harmonic frequencies |
the advanced telescope for high energy astrophysics (athena) is the x-ray observatory large mission selected by the european space agency (esa), within its cosmic vision 2015-2025 programme, to address the "hot and energetic universe" scientific theme (nandra et al. 2013), and it is provisionally due for launch in the ... | ska-athena synergy white paper |
materials exhibiting negative differential resistance have important applications in technologies involving microwave generation, which range from motion sensing to radio astronomy. despite their usefulness, there has been few physical mechanisms giving rise to materials with such properties, i.e. gaas employed in the ... | negative differential resistance and characteristic nonlinear electromagnetic response of a topological insulator |
we extract interstellar scintillation parameters for pulsars observed by the nanograv radio pulsar timing program. dynamic spectra for the observing epochs of each pulsar were used to obtain estimates of scintillation timescales, scintillation bandwidths, and the corresponding scattering delays using a stretching algor... | the nanograv 12.5 year data set: monitoring interstellar scattering delays |
thirteen dwarf galaxies have recently been found to host radio-selected accreting massive black hole (mbh) candidates, some of which are "wandering" in the outskirts of their hosts. we present 9 ghz very long baseline array (vlba) observations of these sources at milliarcsecond resolution. our observations have beam so... | wandering black hole candidates in dwarf galaxies at vlbi resolution |
currently, fast radio bursts (frbs) have become a very active field in astronomy and cosmology. however, the origin of frbs is still unknown to date. the studies on the intrinsic frb distributions might help us to reveal the possible origins of frbs, and improve the simulations for frb cosmology. recently, the first ch... | fast radio burst distributions consistent with the first chime/frb catalog |
we present a new catalog of absolute proper motions and updated positions derived from the same space telescope science institute digitized schmidt survey plates utilized for the construction of guide star catalog ii. as special attention was devoted to the absolutization process and the removal of position, magnitude,... | absolute proper motions outside the plane (apop)&mdasha step toward the gsc2.4 |
the rotational spectra of the two stable conformers syn- and gauche-propanal (ch3ch2cho) were studied in the millimeter and submillimeter wave regions from 75 to 500 ghz with the cologne (sub-)millimeter wave spectrometer. furthermore, the first excited states associated with the aldehyde torsion and with the methyl to... | millimeter and submillimeter wave spectroscopy of propanal |
we report the discovery of the first new pulsar with the murchison widefield array (mwa), psr j0036-1033, a long-period (0.9 s) nonrecycled pulsar with a dispersion measure (dm) of 23.1 pc cm-3. it was found after processing only a small fraction (∼1%) of data from an ongoing all-sky pulsar survey. follow-up observatio... | discovery of a steep-spectrum low-luminosity pulsar with the murchison widefield array |
we present the results from the timing and spectral study of mrk 421 based mainly on the swift data in the x-ray energy range obtained during the time interval 2015 december-2018 april. the most extreme x-ray flaring activity on long-term, daily, and intraday timescales was observed during the 2 month period that start... | swift observations of mrk 421 in selected epochs. iii. extreme x-ray timing/spectral properties and multiwavelength lognormality during 2015 december-2018 april |
a search for astrophysical pointlike neutrino sources using the data collected by the antares detector between 2007 january 29 and 2017 december 31 is presented. a likelihood method is used to assess the significance of an excess of muon neutrinos inducing track-like events in correlation with the location of a list of... | antares search for point sources of neutrinos using astrophysical catalogs: a likelihood analysis |
using the five-hundred-meter aperture spherical radio telescope (fast), we have recorded ∼105 single pulses from psr j1022+1001. we studied the polarization properties, their energy distribution, and their times of arrival. this is only possible with the high sensitivity available using fast. there is no indication tha... | a single-pulse study of psr j1022+1001 using the fast radio telescope |
fast radio bursts (frbs) are mysterious radio transients whose physical origin is still unknown. within a few astronomical units near an frb source, the electric field of the electromagnetic wave is so large that the electron oscillation velocity becomes relativistic, which makes the classical thomson scattering theory... | fast radio bursts as strong waves interacting with the ambient medium |
giant radio pulses (grps) are sporadic bursts emitted by some pulsars that last a few microseconds and are hundreds to thousands of times brighter than regular pulses from these sources. the only grp-associated emission outside of radio wavelengths is from the crab pulsar, where optical emission is enhanced by a few pe... | enhanced x-ray emission coinciding with giant radio pulses from the crab pulsar |
3c 286 is a well-known calibrator source in radio astronomy. it is also one of very few compact steep-spectrum (css) sources detected in γ-rays. here, we perform a detailed spectroscopic and variability analysis and present the first quasi-simultaneous optical to x-ray spectral energy distribution (sed) in order to rev... | spectroscopic classification, variability, and sed of the fermi-detected css 3c 286: the radio-loudest nls1 galaxy? |
context. lyman-α (lyα) is the brightest emission line in star-forming galaxies. however, its interpretation in terms of physical properties is hampered by the resonant nature of lyα photons. in order to remedy this complicated situation, the lyman alpha reference sample (lars) was defined, enabling the study of lyα pro... | the lyman alpha reference sample. xi. efficient turbulence-driven lyα escape and an analysis of ir, co, and [c ii]158 μm |
cubesats are small satellites built in standard sizes and form factors, which have been growing in popularity but have thus far been largely ignored within the field of astronomy. when deployed as space-based telescopes, they enable science experiments not possible with existing or planned large space missions, filling... | on the verge of an astronomy cubesat revolution |
one key challenge in detecting a 21 cm cosmological signal at z > 6 is to separate the cosmological signal from foreground emission. this can be studied in a power spectrum space where the foreground is confined to low delay (or, equivalently, k ∥) modes, whereas the cosmological signal can spread out to high delay ... | the impact of beam variations on power spectrum estimation for 21 cm cosmology. ii. mitigation of foreground systematics for hera |
clean is an iterative deconvolution method for radio and hard-x-ray solar imaging. in a specific step of its pipeline, clean requires the convolution between an idealized version of the instrumental point-spread function (psf), and a map collecting point sources located at positions from where most of the flaring radia... | unbiased clean for stix in solar orbiter |
a quarter century after the detection of the last interstellar carboxylic acid, acetic acid (ch3cooh), we report the discovery of a new one, the cis-trans form of carbonic acid (hocooh), toward the galactic center molecular cloud g+0.693-0.027. hocooh stands as the first interstellar molecule containing three oxygen at... | discovery of the elusive carbonic acid (hocooh) in space |
context. the availability of large bandwidth receivers for millimeter radio telescopes allows for the acquisition of position-position-frequency data cubes over a wide field of view and a broad frequency coverage. these cubes contain a lot of information on the physical, chemical, and kinematical properties of the emit... | deep learning denoising by dimension reduction: application to the orion-b line cubes |
the physical origin of fast radio bursts (frbs) remains unclear. finding multiwavelength counterparts of frbs can provide a breakthrough for understanding their nature. in this work, we perform a systematic search for astronomical transients whose positions are consistent with frbs. we find an unclassified optical tran... | at2020hur: a possible optical counterpart of frb 180916b |
indirect detection of dark matter (dm) by multiwavelength astronomical observations provides a promising avenue for probing the particle nature of dm. in the case of dm consisting of weakly interacting massive particles (wimps), self-annihilation ultimately produces various observable products including e± pairs and ga... | multiwavelength analysis of annihilating dark matter as the origin of the gamma-ray emission from m31 |
the next-generation, broadband geodetic very long baseline interferometry system, named vgos, is developing its global network, and vgos networks with a small size of 3-7 stations have already made broadband observations from 2017 to 2019. we made quality assessments for two kinds of observables in the 21 vgos sessions... | observable quality assessment of broadband very long baseline interferometry system |
the ability to detect ultrafast waveforms arising from randomly occurring events is essential to such diverse fields as bioimaging, spectroscopy, radio-astronomy, sensing and telecommunications. however, noise remains a significant challenge to recover the information carried by such waveforms, which are often too weak... | full recovery of ultrafast waveforms lost under noise |
the discovery of ubiquitous habitable extrasolar planets, combined with revolutionary advances in instrumentation and observational capabilities, has ushered in a renaissance in the search for extraterrestrial intelligence (seti). large scale seti activities are now underway at numerous international facilities. the fi... | opportunities to search for extraterrestrial intelligence with the fast |
discovering pulsars is a significant and meaningful research topic in the field of radio astronomy. with the advent of astronomical instruments such as he five-hundred-meter aperture spherical telescope (fast) in china, data volumes and data rates are exponentially growing. this fact necessitates a focus on artificial ... | pulsar candidate identification with artificial intelligence techniques |
we present the generalized polarization calibration pipeline (gpcal), an automated pipeline for instrumental polarization calibration of very long baseline interferometry (vlbi) data. the pipeline is designed to achieve a high calibration accuracy by means of fitting the instrumental polarization model, including the s... | gpcal: a generalized calibration pipeline for instrumental polarization in vlbi data |
blazars are active galactic nuclei with their relativistic jets pointing toward the observer, comprising two major subclasses, flat-spectrum radio quasars (fsrqs) and bl lac objects. we present multiwavelength photometric and spectroscopic monitoring observations of the blazar b2 1420+32, focusing on its outbursts in 2... | the changing-look blazar b2 1420+32 |
while still in its infancy, the budding field of gravitational-wave astronomy has so far exceeded most expectations, and the achievements that have already been made bode well for the decade to come. while the discoveries made possible by ligo have captured the imagination of experts and nonexperts alike, it is importa... | astro2020 decadal science white paper: the state of gravitational-wave astrophysics in 2020 |
radio pulsar signals are significantly perturbed by their propagation through the ionized interstellar medium. in addition to the frequency-dependent pulse times of arrival due to dispersion, pulse shapes are also distorted and shifted, having been scattered by the inhomogeneous interstellar plasma, affecting pulse arr... | deconvolving pulsar signals with cyclic spectroscopy: a systematic evaluation |
to make a power spectrum (ps) detection of the 21-cm signal from the epoch of reionisation (eor), one must avoid/subtract bright foreground sources. sources such as fornax a present a modelling challenge due to spatial structures spanning from arc seconds up to a degree. we compare modelling with multi-scale (ms) clean... | modelling and peeling extended sources with shapelets: a fornax a case study |
the age of a supernova remnant (snr) is, though undoubtedly one of the most important properties for study of its evolution, difficult to estimate reliably in most cases. in this study, we compare the dynamical and plasma ages of the snrs and characteristic ages of their associated pulsars with the corresponding snrs' ... | quantitative age estimation of supernova remnants and associated pulsars |
context. time variability of astronomical sources provides crude information on their typical size and on the implied physical mechanisms. pks 1830−211 is a remarkable radio-bright lensed quasar with a foreground molecular absorber in the lens galaxy at z = 0.89. small-scale morphological changes in the core-jet struct... | cosmo-tomography toward pks 1830−211: variability of the quasar and of its foreground molecular absorption monitored with alma |
we present a multiwavelength study of ic 860, a nearby post-starburst galaxy at the early stage of transitioning from blue and star forming to red and quiescent. optical images reveal a galaxy-wide, dusty outflow originating from a compact core. we find evidence for a multiphase outflow in the molecular and neutral gas... | a multiwavelength view of ic 860: what is in action inside quenching galaxies |
the detection of the first electromagnetic counterpart to the binary neutron star (bns) merger remnant gw170817 established the connection between short γ-ray bursts and bns mergers. it also confirmed the forging of heavy elements in the ejecta (a so-called kilonova) via the r-process nucleosynthesis. the appearance of... | probing the magnetic field in the gw170817 outflow using h.e.s.s. observations |
we present long-term (2012-2022) optical monitoring of the candidate black hole x-ray binary swift j1910.2-0546 with the faulkes telescopes and las cumbres observatory network. following its initial bright 2012 outburst, we find that the source displayed a series of at least seven quasi-periodic, high-amplitude (~3 mag... | seven reflares, a mini outburst, and an outburst: high-amplitude optical variations in the black hole x-ray binary swift j1910.2-0546 |
the concept of a multi-functional astronomical complex as applied to robotic astronomy networks and systems is formulated. the practical realization of this concept in the master global network of robotic telescopes of moscow state university is described. the dynamically integrated master database, which transforms a ... | the concept of a multi-functional astronomy complex and dynamically integrated database applied to multi-channel observations with the master global network |
one of the major priorities of international radio astronomy is to study the early universe through the detection of the 21 cm hi line from the epoch of reionisation (eor). due to the weak nature of the 21 cm signal, an important part in the detection of the eor is removing contaminating foregrounds from our observatio... | imaging the southern sky at 159 mhz using spherical harmonics with the engineering development array 2 |
the ages and durations of the stages in the early cretaceous commonly show discrepancies of several million years when the geologic time scale (2020) from the international commission of stratigraphy (ics) and recently published radio-astrochronologic data are compared. here, we provide an astronomical time scale for t... | integrated astrochronology of the barremian stage (early cretaceous) and its biostratigraphic subdivisions |
radio frequency interference (rfi) detection and excision are key steps in the data-processing pipeline of the five-hundred-meter aperture spherical radio telescope (fast). because of its high sensitivity and large data rate, fast requires more accurate and efficient rfi flagging methods than its counterparts. in the l... | deep residual detection of radio frequency interference for fast |
the detection of non-repeating or irregular events in time-domain radio astronomy has gained importance over the last decade due to the discovery of fast radio bursts. existing or upcoming radio telescopes are gathering more and more data, and consequently, the software, which is an important part of these telescopes, ... | single-pulse detection algorithms for real-time fast radio burst searches using gpus |
the square kilometre array telescope at low-frequency (ska-low) will be a phased array telescope supporting a wide range of science cases covering the frequency band 50 - 350 mhz, while at the same time asking for high sensitivity and excellent characteristics. these extremely challenging requirements resulted in a des... | a prototype model for evaluating ska-low station calibration |
a measurement of the cosmological 21 {cm} signal remains a promising but as-of-yet unattained ambition of radio astronomy. a positive detection would provide direct observations of key unexplored epochs of our cosmic history, including the cosmic dark ages and reionization. in this paper, we concentrate on measurements... | measuring the cosmological 21 cm monopole with an interferometer |
much data on the galactic polarized radio emission has been gathered in the last five decades. all-sky surveys have been made, but only in narrow, widely spaced frequency bands—and the data are inadequate for the characterization of faraday rotation, the main determinant of the appearance of the polarized radio sky at ... | the global magneto-ionic medium survey: polarimetry of the southern sky from 300 to 480 mhz |
the radio arc is one of the brightest systems of nonthermal filaments (ntfs) in the galactic center, located near several prominent h ii regions (sickle and pistol) and the quintuplet stellar cluster. we present observations of the arc ntfs using the s, c, and x bands of the very large array interferometer. our images ... | a vla polarimetric study of the galactic center radio arc: characterizing polarization, rotation measure, and magnetic field properties |
the galaxy cluster rx j0603.3+4214 at z = 0.225 is one of the rarest clusters boasting an extremely large (∼2 mpc) radio relic. because of the remarkable morphology of the relic, the cluster is nicknamed the “toothbrush cluster.” although the cluster's underlying mass distribution is one of the critical pieces of infor... | mc2: mapping the dark matter distribution of the "toothbrush" cluster rx j0603.3+4214 with hubble space telescope and subaru weak lensing |
long-term observations of synchrotron emission from supernovae (sne), covering more than a year after the explosion, provide a unique opportunity to study the poorly understood evolution of massive stars in the final millennium of their lives via changes in the mass-loss rate. here we present a result of our long-term ... | resurrection of type iil supernova 2018ivc: implications for a binary evolution sequence connecting hydrogen-rich and hydrogen-poor progenitors |
the commensal real-time australian square kilometre array pathfinder fast transients survey is the first extensive astronomical survey using phased array feeds. since january 2017, it has been searching for fast radio bursts in fly's eye mode. here, we present a calculation of the sensitivity and total exposure of the ... | the performance and calibration of the craft fly's eye fast radio burst survey |
the operational period of the first generation of dedicated space vlbi (svlbi) missions commenced in 1997 with the launch of the japan-led mission vsop/halca and is coming to closure in 2019 with the completion of in-flight operations of the russia-led mission radioastron. they were preceded by the svlbi demonstration ... | space vlbi: from first ideas to operational missions |
the binary system v404 cygni consists of a red giant star orbiting a black hole. in 2015, a surge of accretion by the black hole caused the surrounding plasma to brighten suddenly for the first time since 1989, briefly becoming the brightest x-ray source in the sky. dallilar et al. combined observations from radio, inf... | a precise measurement of the magnetic field in the corona of the black hole binary v404 cygni |
though the neutrino-driven convection model for the core-collapse explosion mechanism has received strong support in recent years, there are still many uncertainties in the explosion parameters—such as explosion energy, remnant mass, and end-of-life stellar abundances as initial conditions. using a broad set of spheric... | the nucleosynthetic yields of core-collapse supernovae: prospects for the next generation of gamma-ray astronomy |
we report barely visible detection of a radio burst (s/n =5.1) from the recently discovered fast radio burst frb20220912a (atel #15679) in october 2022 daily archived data with the big scanning antenna (bsa) at 111 mhz of the pushchino radio astronomy observatory. | detection of frb 20220912a at 111 mhz with bsa radio telescope |
we use the combined array for research in millimeter-wave astronomy (carma) millimeter interferometer to map the antennae galaxies (ngc 4038/39), tracing the bulk of the molecular gas via the 12co(1-0) line and denser molecular gas via the high density transitions hcn(1-0), hco+(1-0), cs(2-1), and hnc(1-0). we detect b... | dense gas fraction and star-formation efficiency variations in the antennae galaxies |
the recently published fourth fermi large area telescope source catalog (4fgl) reports 5065 gamma-ray sources in terms of direct observational gamma-ray properties. among the sources, the largest population is the active galactic nuclei (agns), which consists of 3137 blazars, 42 radio galaxies, and 28 other agns. the b... | evaluating the classification of fermi bcus from the 4fgl catalog using machine learning |
context. c-cyanomethanimine (hnchcn), existing in the two z and e isomeric forms, is a key prebiotic molecule, but, so far, only the e isomer has been detected toward the massive star-forming region sagittarius b2(n) using transitions in the radio wavelength domain.aims: with the aim of detecting hnchcn in sun-like-sta... | laboratory measurements and astronomical search for cyanomethanimine |
uncertainty quantification is a critical missing component in radio interferometric imaging that will only become increasingly important as the big-data era of radio interferometry emerges. statistical sampling approaches to perform bayesian inference, like markov chain monte carlo (mcmc) sampling, can in principle rec... | uncertainty quantification for radio interferometric imaging: ii. map estimation |
we present 1 mm observations constructed from atacama large (sub)millimeter array (alma) data of so2, so, and kcl when io went from sunlight into eclipse (2018 march 20) and vice versa (2018 september 2 and 11). there is clear evidence of volcanic plumes on march 20 and september 2. the plumes distort the line profiles... | alma observations of io going into and coming out of eclipse |
fast radio bursts (frbs) are one of the most mysterious astronomical transients. observationally, they can be classified into repeaters and apparent non-repeaters. however, due to the lack of continuous observations, some apparent repeaters may have been incorrectly recognized as non-repeaters. in a series of two paper... | machine learning classification of chime fast radio bursts - ii. unsupervised methods |
the discovery of a fast radio burst (frb) associated with a magnetar in the milky way by the canadian hydrogen intensity mapping experiment frb collaboration (chime/frb) and the survey for transient astronomical radio emission 2 has provided an unprecedented opportunity to refine frb emission models. the burst discover... | scintillation can explain the spectral structure of the bright radio burst from sgr 1935+2154 |
ss433 is a galactic microquasar with powerful jets, where very-high-energy particles are produced. we study particle acceleration in the jets of ss433 through the use of recent multiwavelength data from radio to tev gamma-ray. we first present a general framework for the particle acceleration, cooling, and transport in... | multiwavelength emission from galactic jets: the case of the microquasar ss433 |
a likely detection of γ-ray emission from the region of kepler's supernova remnant (snr) is reported by analyzing ∼12 yr of pass 8 data of the fermi large area telescope. its photon flux is (4.85 ± 0.60) × 10-10 ph cm-2 s-1 with ∼4σ significance in 0.2-500 gev. moreover, our results show that there is no significant va... | detection of gev gamma-ray emission of kepler's snr with fermi-lat |
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