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the recent detection of the m dwarf gj 1151 at 144 mhz low radio frequencies using lofar has been interpreted as evidence of an exoplanet magnetically interacting with its host star. this would be the first exoplanet detected around a main-sequence star by a radio telescope. radial velocity confirmation of such a plane... | the tess view of lofar radio-emitting stars |
recently the icecube collaboration detected very high energy (vhe) neutrinos and associated them with the blazar txs 0506+056, raising a possible association of vhe neutrinos with this and other individual blazars. very long baseline interferometry (vlbi) is so far the only technique enabling the imaging of the innermo... | the parsec-scale jet of the neutrino-emitting blazar txs 0506+056 |
characterizing habitable exoplanets and/or their moons is of paramount importance. here we show the results of our magnetic field topological modeling, which demonstrate that terrestrial exoplanet-exomoon coupled magnetospheres work together to protect the early atmospheres of both the exoplanet and the exomoon. when e... | magnetospheres of terrestrial exoplanets and exomoons: implications for habitability and detection |
among the ~2157 unassociated sources in the third data release (dr3) of the fourth fermi catalog, ~1200 were observed with the neil gehrels swift observatory pointed instruments. these observations yielded 238 high signal-to-noise ratio x-ray sources within the 95% fermi uncertainty regions. recently, kerby et al. empl... | using neural networks to differentiate newly discovered bl lacertae objects and fsrqs among the 4fgl unassociated sources employing gamma-ray, x-ray, uv/optical, and ir data |
we present atacama large millimeter/submillimeter array observations at ≈100 ghz with 0.″05 (3 pc) resolution of the kiloparsec-scale jet seen in the nearby seyfert galaxy ngc 1068, and we report the presence of parsec-scale blobs at the head of the jet. the combination of the detected radio flux (≈0.8 mjy), spectral i... | alma detection of parsec-scale blobs at the head of a kiloparsec-scale jet in the nearby seyfert galaxy ngc 1068 |
eight new class ii methanol masers selected from the 6.7 ghz methanol multibeam survey catalogues i and ii were monitored at 6.7 ghz with the 26 m hartebeesthoek radio astronomy observatory radio telescope for three years and seven months, from 2011 february to 2014 september. the sources were also observed at 12.2 ghz... | new periodic 6.7 ghz class ii methanol maser associated with g358.460-0.391 |
the sardinia radio telescope (srt) is a 64-m, fully-steerable single-dish radio telescope that was recently commissioned both technically and scientifically with regard to the basic observing modes. in order to improve the scientific capability and cover all the requirements for an advanced single-dish radio telescope,... | sardinia roach2-based digital architecture for radio astronomy (sardara) |
the common phenomenon of lightning still harbors many secrets such as what are the conditions for lightning initiation and what is driving the discharge to propagate over several tens of kilometers through the atmosphere forming conducting ionized channels called leaders. since lightning is an electric discharge phenom... | a distinct negative leader propagation mode |
polycyclic aromatic hydrocarbons (pahs) are highly relevant for astrophysics as possible, though controversial, carriers of the unidentified infrared emission bands that are observed in a number of different astronomical objects. in support of radio-astronomical observations, high resolution laboratory spectroscopy has... | rotation-vibration interactions in the spectra of polycyclic aromatic hydrocarbons: quinoline as a test-case species |
we report the discovery of the bl lacertae object first j233153.20+112952.11 at redshift >6 using near-infrared spectroscopy and broadband observations in the infrared, submillimeter, and radio wavelengths. the detection of the continuum break at ~0.92 μm in the near-infrared spectrum of first j233153.20+112952.11 p... | a bl lacertae object at a cosmic age of 800 myr |
the casacore table data system (ctds) has been developed as part of the casa (formerly aips++) package for (radio-)astronomical data processing. it offers a relational-like data model extended by the ability to store large arrays. a versatile query language can be used for data queries and manipulation. ctds forms the ... | casacore table data system and its use in the measurementset |
multi-wavelength and multi-messenger astronomy will reveal the phenomena that produce fast radio bursts, turning fast radio bursts into sharper tools with which to probe extragalactic plasma. | multiple messengers of fast radio bursts |
the large-scale radio/microwave sky has been mapped over a range of frequencies from tens of mhz to tens of ghz, in intensity and polarization. the emission is primarily synchrotron radiation from cosmic ray electrons spiralling in the galactic magnetic field, in addition to free–free radiation from warm ionized gas. a... | large-scale features of the radio sky and a model for loop i |
fast radio bursts (frbs) are puzzling, millisecond, energetic radio transients with no discernible source; observations show no counterparts in other frequency bands. the birth of a quark star from a parent neutron star experiencing a quark nova - previously thought undetectable when born in isolation - provides a natu... | quark nova model for fast radio bursts |
the literature on horn antennas dedicated to radio astronomy and satellite communications applications is very extensive and at times disjointed, relevant contributions being distributed as far back as from the 60's until the present today. this work combines a compact but complete review of the different theories, met... | fundamentals of horn antennas with low cross-polarization levels for radioastronomy and satellite communications |
massive young stellar objects (mysos) have recently been shown to drive jets whose particles can interact with either the magnetic fields of the jet or ambient medium to emit non-thermal radiation. we report a search for non-thermal radio emission from a sample of 15 mysos to establish the prevalence of the emission in... | a search for non-thermal radio emission from jets of massive young stellar objects |
during the last decades, increasingly precise astronomical observations of the galactic centre (gc) region at radio, infrared, and x-ray wavelengths laid the foundations to a detailed understanding of the high energy astroparticle physics of this most remarkable location in the galaxy. recently, observations of this re... | gamma rays from the galactic centre region: a review |
one of the tightest correlations in astronomy is the relation between the integrated radio continuum and the far-infrared (fir) emission. within nearby galaxies, variations in the radio-fir correlation have been observed, mainly because the cosmic ray electrons migrate before they lose their energy via synchrotron emis... | deciphering the radio star formation correlation on kpc scales. i. adaptive kernel smoothing experiments |
there is mounting evidence that the composition and structure of planetary systems are intimately linked to their birth environments. during the past decade, several spectral surveys probed the chemistry of the earliest stages of star formation and late planet-forming disks. however, very little is known about the chem... | a 3 mm chemical exploration of small organics in class i ysos |
the upcoming square kilometre array (ska) radio telescope will become the largest astronomical observation facility, and is expected to introduce revolutionary changes in major fields of natural sciences. these revolutionary changes help us to answer the fundamental questions related to the origins of the universe, lif... | science opportunities and challenges associated with ska big data |
advanced ligo and virgo have reported 90 confident gravitational-wave (gw) observations from compact-binary coalescences from their three observation runs. in addition, numerous subthreshold gw candidates have been identified. binary neutron star (bns) mergers can produce gws and short-gamma-ray bursts, as confirmed by... | search for coincident gravitational-wave and fast radio burst events from 4-ogc and the first chime/frb catalog |
superclusters are the largest objects in the universe, and they provide a unique opportunity to study how galaxy clusters are born at the junction of the cosmic web as well as the distribution of magnetic fields and relativistic particles beyond cluster volume. the field of radio astronomy is going through an exciting ... | moss i: double radio relics in the saraswati supercluster |
the first non-electromagnetic messengers from space were discovered in the early 20th century, but it is only now that multimessenger astronomy is coming into its own. the aim of <italic>multimessenger astronomy in practice</italic> is to aid an astronomer who is new to research in a particular area of mult... | multimessenger astronomy in practice |
motivated by the desire for wide-field images with well-defined statistical properties for 21 cm cosmology, we implement an optimal mapping pipeline that computes a maximum likelihood estimator for the sky using the interferometric measurement equation. we demonstrate this "direct optimal mapping" with data from the hy... | direct optimal mapping for 21 cm cosmology: a demonstration with the hydrogen epoch of reionization array |
observations of supernova remnants (snrs) are a powerful tool for investigating the later stages of stellar evolution, the properties of the ambient interstellar medium and the physics of particle acceleration and shocks. for a fraction of snrs, multiwavelength coverage from radio to ultra-high energies has been provid... | imaging of snr ic443 and w44 with the sardinia radio telescope at 1.5 and 7 ghz |
circumstellar environments of oxygen-rich stars are among the strongest sio maser emitters. physical processes such as collisions, infrared pumping, and overlaps favor the inversion of level population and produce maser emission at different vibrational states. despite numerous observational and theoretical efforts, we... | sio, 29sio, and 30sio emission from 67 oxygen-rich stars: a survey of 61 maser lines from 7 to 1 mm |
we report the detection of three bright bursts from the repeating frb 20201124a with the nanshan 26-m (nsrt) radio telescope operated by xinjiang astronomical observatory (xao). | detection of bright bursts from the repeating frb 20201124a with the xinjiang nanshan 26-m radio telescope |
we report the discovery of three millisecond pulsars (msps): psrs j1120-3618, j1646-2142, and j1828+0625 with the giant metrewave radio telescope (gmrt) at a frequency of 322 mhz using a 32 mhz observing bandwidth. these sources were discovered serendipitously while conducting the deep observations to search for millis... | serendipitous discovery of three millisecond pulsars with the gmrt in fermi-directed survey and follow-up radio timing |
part i. spectral line investigations; part ii. point sources; part iii. galactic structure and statistical studies of point sources; part iv. the quiet sun; part v. the active sun; part vi. meteors and planets. | radio astronomy |
the primary purpose of the international very long baseline interferometry (vlbi) service for geodesy and astrometry intensive sessions is the rapid estimation of ut1-tai. improving the robustness and the precision of the ut1 estimates from the intensives is an important goal. the int01 series, which usually uses the k... | improvement of the ivs-int01 sessions by source selection: development and evaluation of the maximal source strategy |
we report the detection of linearly polarized emission at 53 and 89 μm from the radio-loud active galactic nucleus (agn) cygnus a using high-resolution airborne wideband camera-plus (hawc+) on board the stratospheric observatory for infrared astronomy (sofia). we measure a highly polarized core of 11 ± 3% and 9 ± 2% wi... | the highly polarized dusty emission core of cygnus a |
this overview provides a historical perspective highlighting the pioneering role which the fairly modest observational facilities of aries have played since the 1990s in systematically characterizing the optical variability on hour-like time scale (intra-night optical variability, or inov) of several major types of hig... | optical monitoring of active galactic nuclei from aries |
as radio astronomy enters a golden age, ground-based observatories are reaching sensitivities capable of unlocking a new and exciting field of exoplanet observation. radio observation of planetary auroral emission provides unique and complementary insight into planetary science not available via orthodox exoplanet obse... | detecting magnetospheric radio emission from giant exoplanets |
neutral gas is commonly believed to dominate over stars in the outskirts of galaxies, and investigations of the disk-halo interface are generally considered to be in the domain of radio astronomy. this may simply be a consequence of the fact that deep h i observations typically probe to a lower-mass surface density tha... | the dragonfly nearby galaxies survey. iv. a giant stellar disk in ngc 2841 |
owing to their small interaction cross-section, neutrinos are unparalleled astronomical tracers. ultra-high energy (uhe; e > 10 pev) neutrinos probe the most distant, most explosive sources in the universe, often obscured to optical telescopes. radio-frequency (rf) detection of askaryan radiation in cold polar ice i... | measurement of the real dielectric permittivity ɛr of glacial ice |
highest resolution imaging in astronomy is achieved by interferometry, connecting telescopes over increasingly longer distances and at successively shorter wavelengths. here, we present the first diffraction-limited images in visual light, produced by an array of independent optical telescopes, connected electronically... | optical aperture synthesis with electronically connected telescopes |
we test a new technique for studying magnetohydrodynamic turbulence suggested by lazarian & pogosyan, using synthetic observations of synchrotron polarization. this paper focuses on a one-point statistics, which is termed polarization frequency analysis, that is characterized by the variance of polarized emission a... | studying magnetohydrodynamic turbulence with synchrotron polarization dispersion |
we report a 3d mhd simulation study of the interactions between radio galaxies (rgs) and galaxy-cluster-media shocks in which the incident shock normals are orthogonal to the bipolar active galactic nucleus (agn) jets. before shock impact, light, supersonic jets inflate lobes (cavities) in a static, uniform intracluste... | simulated interactions between radio galaxies and cluster shocks. ii. jet axes orthogonal to shock normals |
a device capable of converting single quanta of the microwave field to the optical domain is an outstanding endeavor in the context of quantum interconnects between distant superconducting qubits, but likewise can have applications in other fields, such as radio astronomy or, in the classical realm, microwave photonics... | quantum coherent microwave-optical transduction using high-overtone bulk acoustic resonances |
the redshifted 21 cm line of neutral hydrogen (h i), potentially observable at low radio frequencies (∼50-200 mhz), is a promising probe of the physical conditions of the intergalactic medium during cosmic dawn and the epoch of reionization (eor). the sky-averaged h i signal is expected to be extremely weak (∼100 mk) i... | the impact of the ionosphere on ground-based detection of the global epoch of reionization signal |
searching for extraterrestrial, transient signals in astronomical data sets is an active area of current research. however, machine learning techniques are lacking in the literature concerning single-pulse detection. this paper presents a new, two-stage approach for identifying and classifying dispersed pulse groups (d... | detection of dispersed radio pulses: a machine learning approach to candidate identification and classification |
context. as radio telescopes increase in sensitivity and flexibility, so do their complexity and data rates. for this reason, automated system health management approaches are becoming increasingly critical to ensure nominal telescope operations.aims: we propose a new machine-learning anomaly detection framework for cl... | the road to discovery: machine-learning-driven anomaly detection in radio astronomy spectrograms |
the fast fourier transform (fft) based periodicity search methods provide an efficient way to search for millisecond and binary pulsars but encounter significant sensitivity degradation while searching for long period and short duty cycle pulsars. an alternative to fft-based search methods called the fast folding algor... | the gmrt high resolution southern sky survey for pulsars and transients. iv. discovery of four new pulsars with an ffa search |
we present a deep learning (dl) pipeline developed for the detection and characterization of astronomical sources within simulated atacama large millimeter/submillimeter array (alma) data cubes. the pipeline is composed of six dl models: a convolutional autoencoder for source detection within the spatial domain of the ... | 3d detection and characterization of alma sources through deep learning |
we have used the arecibo telescope to carry out one of the deepest-ever integrations in radio astronomy, targeting the redshifted conjugate satellite oh 18 cm lines at z ≈0.247 towards pks 1413 +135 . the satellite oh 1720 and 1612 mhz lines are, respectively, in emission and absorption, with exactly the same line shap... | stringent constraints on fundamental constant evolution using conjugate 18 cm satellite oh lines |
titan harbors a dense, organic-rich atmosphere primarily composed of n2 and ch4, with lesser amounts of hydrocarbons and nitrogen-bearing species. as a result of high-sensitivity observations by the atacama large millimeter/submillimeter array (alma) in band 6 (∼230-272 ghz), we obtained the first spectroscopic detecti... | detection of ch3c3n in titan&'s atmosphere |
the interstellar oxygen isotopic ratio of 18o/17o can reflect the relative amount of the secular enrichment by ejecta from high-mass versus intermediate-mass stars. previous observations found a galactic gradient of 18o/17o, i.e., low ratios in the galactic center and large values in the galactic disk, which supports t... | a systematic observational study on galactic interstellar ratio 18o/17o. i. c18o and c17o j = 1-0 data analysis |
the advancement in signal processing and gpu based systems has enabled new transient detectors at various telescopes to perform much more sensitive searches than their predecessors. typically the data output from the telescopes is in one of the two commonly used formats: psrfits and sigproc filterbank. software develop... | your: your unified reader |
the baryon acoustic oscillations from integrated neutral gas observations (bingo) telescope is a 40-m class radio telescope under construction that has been designed to measure the large-angular-scale intensity of hi emission at 980-1260 mhz and hence to constrain dark energy parameters. a large focal plane array compr... | baryon acoustic oscillations from integrated neutral gas observations: broadband corrugated horn construction and testing |
we present detailed observations of photoionization conditions and galaxy kinematics in 11 z = 1.39-2.59 radio-loud quasar host galaxies. data were taken with the osiris integral field spectrograph and the adaptive optics system at the w. m. keck observatory that targeted nebular emission lines (hβ, [o iii], hα, [n ii]... | a spatially resolved survey of distant quasar host galaxies. ii. photoionization and kinematics of the ism |
the five-hundred-meter aperture spherical radio telescope (fast) has started the commensal radio astronomy fast survey (crafts). in this paper, we use the technical parameters of fast derived from commissioning observations to simulate the completeness function for extragalactic h i survey of crafts, h i galaxies from ... | predictions for the fast telescope's crafts extragalactic h i survey |
we report the first detection of hot molecular cores in the small magellanic cloud (smc), a nearby dwarf galaxy with 0.2 solar metallicity. we observed two high-mass young stellar objects in the smc with the atacama large millimeter/submillimeter array and detected emission lines of co, hco+, h13co+, sio, h2co, ch3oh, ... | the detection of hot molecular cores in the small magellanic cloud |
radio frequency interference (rfi) corrupts astronomical measurements, thus affecting the performance of radio telescopes. to address this problem, supervised-segmentation models have been proposed as candidate solutions to rfi detection. however, the unavailability of large labelled data sets, due to the prohibitive c... | learning to detect radio frequency interference in radio astronomy without seeing it |
a search for laser light from proxima centauri was performed, including 107 high-resolution, optical spectra obtained between 2004 and 2019 with the harps spectrometer. the search for laser light involved rejecting sharp peaks in the spectrum from stellar flares, fluorescent city lights, and elementary particles that d... | a search for optical laser emission from proxima centauri |
unknown class distributions in unlabelled astrophysical training data have previously been shown to detrimentally affect model performance due to dataset shift between training and validation sets. for radio galaxy classification, we demonstrate in this work that removing low angular extent sources from the unlabelled ... | learning useful representations for radio astronomy "in the wild" with contrastive learning |
in 2018, the greenland telescope (glt) started scientific observation in greenland. since then, we have completed several significant improvements and added new capabilities to the telescope system. this paper presents a full review of the glt system, a summary of our observation activities since 2018, the lessons lear... | the greenland telescope-construction, commissioning, and operations in pituffik |
many pulsars in the known population exhibit nulling, which is characterized by a sudden cessation and subsequent restoration of radio emission. in this work, we present the localization, timing, and emission properties of a pulsar discovered by the gmrt high resolution southern sky survey: j1244-4708. moreover, we fin... | the gmrt high resolution southern sky survey for pulsars and transients. vi. discovery of nulling, localization, and timing of psr j1244-4708 |
a sensitive (1σ rms ≤ 3 mk; 2 mhz resolution) 1 mm spectral survey (214.5-285.5 ghz) of the envelope of the oxygen-rich supergiant star nml cygni (nml cyg) has been conducted using the 10 m submillimeter telescope of the arizona radio observatory. these data represent the first spectral line survey of nml cyg and are c... | the arizona radio observatory 1 mm spectral survey of the hypergiant star nml cygni (215-285 ghz) |
detecting cosmological signals from the epoch of reionization (eor) requires high-precision calibration to isolate the cosmological signals from foreground emission. in radio interferometry, the perturbed primary beams of antenna elements can disrupt the precise calibration, which results in the contamination of the fo... | the impact of beam variations on power spectrum estimation for 21 cm cosmology. i. simulations of foreground contamination for hera |
a new interstellar molecule, fec (x 3δ i ), has been identified in the circumstellar envelope of the carbon-rich asymptotic giant branch star irc+10216. fec is the second iron-bearing species conclusively observed in the interstellar medium, in addition to fecn, also found in irc+10216. the j = 4 → 3, 5 → 4, and 6 → 5 ... | elusive iron: detection of the fec radical (x 3δ i ) in the envelope of irc+10216 |
to date, the search for radio technosignatures has focused on sky location as a primary discriminant between technosignature candidates and anthropogenic radio frequency interference (rfi). in this work, we investigate the possibility of searching for technosignatures by identifying the presence and nature of intensity... | on detecting interstellar scintillation in narrowband radio seti |
we present high-resolution (≲0.″1) atacama large millimeter/submillimeter array observations of the strongly lensed galaxy hatlasj113526.2-01460 at redshift z ~ 3.1, discovered in the gama 12th field of the herschel-atlas survey. this gravitationally lensed system is remarkably peculiar, in that neither the background ... | alma resolves the first strongly lensed optical/near-ir-dark galaxy |
large constellations of bright artificial satellites in low earth orbit pose significant challenges to ground-based astronomy1. current orbiting constellation satellites have brightnesses between apparent magnitudes 4 and 6, whereas in the near-infrared ks band, they can reach magnitude 2 (ref. 2). satellite operators,... | the high optical brightness of the bluewalker 3 satellite |
gamma-ray emission provides constraints on the nonthermal radiation processes at play in astrophysical particle accelerators. this allows both the nature of accelerated particles and the maximum energy that they can reach to be determined. notably, it remains an open question to what extent supernova remnants contribut... | fermi-lat detection of the supernova remnant g312.4-0.4 in the vicinity of 4fgl j1409.1-6121e |
new science drivers have recently emerged in radio astronomy for observation of low-frequency radio waves, below 30 mhz. exploring this frequency requires a space-based radio telescope with a very large aperture that is impossible to realize in a monolithic fashion. a distributed system consisting of a swarm of 50 or m... | swarm-to-earth communication in olfar |
psrdada supports the development of distributed data acquisition and analysis systems; it provides a flexible and well-managed ring buffer in shared memory with a variety of applications for piping data from device to ring buffer and from ring buffer to device. psrdada allows more than one data set to be queued in the ... | psrdada: distributed acquisition and data analysis for radio astronomy |
auroral kilometric radiation (akr) is terrestrial radio emission that originates in particle acceleration regions along magnetic field lines, coinciding with discrete auroral arcs. akr viewing geometry is complex due to the confinement of the source regions to nightside local times (lts) and the anisotropy of the beami... | empirical selection of auroral kilometric radiation during a multipoint remote observation with wind and cassini |
the simultaneous detection of electromagnetic and gravitational waves from the coalescence of two neutron stars (gw170817 and grb170817a) has ushered in a new era of 'multimessenger' astronomy, with electromagnetic detections spanning from gamma to radio. this great opportunity for new scientific investigations raises ... | dynamic scheduling: target of opportunity observations of gravitational wave events |
the current understanding of the characteristics of solar and inner heliospheric electron events is inferred almost entirely from observations made by spacecraft located at 1 astronomical unit (au). previous observations within 1 au of the sun, by the helios spacecraft at ∼0.3-1 au, indicate the presence of electron ev... | small electron events observed by parker solar probe/is⊙is during encounter 2 |
low phase noise frequency synthesizers are of paramount interest in many areas of micro-mm wave technology, encompassing for example advanced wireless communication, radar, radio-astronomy, and precision instrumentation. although this broad research field is not bereft of methods for the generation of either low phase ... | a photonic frequency discriminator based on a two wavelength delayed self-heterodyne interferometer for low phase noise tunable micro/mm wave synthesis |
cross-matching catalogues at different wavelengths is a difficult problem in astronomy, especially when the objects are not point-like. at radio wavelengths, an object can have several components corresponding, for example, to a core and lobes. considering not all radio detections correspond to visible or infrared sour... | matching radio catalogues with realistic geometry: application to swire and atlas |
using 1 cm and 3 mm observations from the combined array for research in millimeter-wave astronomy and 2 mm observations from the goddard iram superconducting 2 millimeter observer observations, we follow up the first extragalactic detection of anomalous microwave emission (ame) reported by murphy et al. in an extranuc... | characterizing extragalactic anomalous microwave emission in ngc 6946 with carma |
we analyze an extremely deep 450 μm image (1σ = 0.56 mjy beam-1) of a ≃300 arcmin2 area in the candels/cosmos field as part of the sub-millimeter common user bolometric array-2 ultra deep imaging eao survey. we select a robust (signal-to-noise ratio ≥4) and flux-limited (≥4 mjy) sample of 164 submillimeter galaxies (sm... | scuba-2 ultra deep imaging eao survey (studies). iv. spatial clustering and halo masses of submillimeter galaxies |
multimessenger astronomy, combining gravitational-wave (gw) and electromagnetic-wave (em) observations, has a huge impact on physics, astrophysics, and cosmology. however, the majority of sources detected with currently running ground-based gw observatories are binary black hole (bbh) mergers, which disappointingly wer... | where are the electromagnetic-wave counterparts of stellar-mass binary black hole mergers? |
context. the sensitivity of a radio interferometer is a key figure of merit (fom) for a radio telescope. the sensitivity of a single polarized interferometer is typically given as an antenna effective area over a system temperature, ae/tsys, assuming an unpolarized source. for a dual-polarized polarimetric interferomet... | sensitivity of a low-frequency polarimetric radio interferometer |
we report the results of our optical (vri) photometric observations of the tev blazar 1es 0806+524 on 153 nights during 2011-2019 using seven optical telescopes in europe and asia. we investigated the variability of the blazar on intraday as well as on long-term timescales. we examined 18 intraday light curves for flux... | optical variability of the tev blazar 1es 0806+524 on diverse timescales |
we present a calibration component for the murchison widefield array all-sky virtual observatory (mwa asvo) utilising a newly developed postgresql database of calibration solutions. since its inauguration in 2013, the mwa has recorded over 34 petabytes of data archived at the pawsey supercomputing centre. according to ... | calibration database for the murchison widefield array all-sky virtual observatory |
we report tev gamma-ray observations of the ultra-high-energy source mgro j1908+06 using data from the high altitude water cherenkov observatory. this source is one of the highest-energy known gamma-ray sources, with emission extending past 200 tev. modeling suggests that the bulk of the tev gamma-ray emission is lepto... | hawc study of the ultra-high-energy spectrum of mgro j1908+06 |
we describe the gems of the galaxy zoos (zoo gems) project, a gap-filler project using short windows in the hubble space telescope's schedule. as with previous snapshot programs, targets are taken from a pool based on position; we combine objects selected by volunteers in both the galaxy zoo and radio galaxy zoo citize... | gems of the galaxy zoos-a wide-ranging hubble space telescope gap-filler program |
modeling of frequency-dependent effects, contributed by the turbulence in the free electron density of interstellar plasma, is required to enable the detection of the expected imprints from the stochastic gravitational-wave (gw) background in pulsar timing data. in this work, we present an investigation of temporal var... | wide-band timing of gmrt-discovered millisecond pulsars |
the empirical relationship between the nonthermal 5 ghz radio luminosity and the soft x-ray luminosity of active stellar coronae, canonically called the güdel-benz relationship, has been a cornerstone of stellar radio astronomy, as it explicitly ties the radio emission to the coronal heating mechanisms. the relationshi... | peculiar radio-x-ray relationship in active stars |
surveys conducted by radio astronomy observatories, such as ska, meerkat, very large array, and askap, have generated massive astronomical images containing radio galaxies (rgs). this generation of massive rg images has imposed strict requirements on the detection and classification of rgs and makes manual classificati... | automatic detection and classification of radio galaxy images by deep learning |
we follow up on the surprising recent announcement by vernstrom et al. (2021, mnras) of the detection of the synchrotron cosmic web. we attempt to reproduce their detection with new observations with the phase ii, extended configuration of the murchison widefield array at 118.5 mhz. we reproduce their detection methodo... | searching for the synchrotron cosmic web again: a replication attempt |
we have measured an annual parallax of the mira variable r ursae majoris (r uma) with the vlbi exploration for radio astronomy (vera). from the monitoring vlbi observations over a span of about two years, we detected h2o maser spots in the lsr velocity range from 37 to 42 km s-1. we derived an annual parallax of 1.97 ±... | parallax of a mira variable r ursae majoris studied with astrometric vlbi |
the central molecular zone, covering the inner ∼1° of the galactic plane has been mapped at 2 mm using the goddard-iram superconducting 2-millimeter observer (gismo) bolometric camera on the 30 m iram telescope. the 21″ resolution maps show abundant emission from cold molecular clouds, from star-forming regions, and fr... | 2 mm gismo observations of the galactic center. i. dust emission |
we summarize our current state of knowledge of fast radio bursts (frbs) which were first discovered a decade ago. following an introduction to radio transients in general, including pulsars and rotating radio transients, we discuss the discovery of frbs. we then discuss frb follow-up observations in the context of repe... | fast radio bursts |
ghz radio astronomy has played a fundamental role in the recent dazzling discovery of gw170817, a neutron star (ns)-ns merger observed in both gravitational waves (gws) and light at all wavelengths. here we show how the expected progress in sensitivity of ground-based gw detectors over the next decade calls for u.s.-ba... | astro2020 science white paper: radio counterparts of compact object mergers in the era of gravitational-wave astronomy |
the prospects of the progress of radio astronomy, solar energy, as well as the exploration of the earth surface and other planets from space are inherently linked to the possibility of deploying large structures (telescopes, antennas, energy platforms and so on) in space. these structures will be delivered to the space... | mathematical modeling of the deployment of a large transformable space structure |
hc3n is a ubiquitous molecule in interstellar environments, from external galaxies to galactic interstellar clouds, star-forming regions, and planetary atmospheres. observations of its rotational and vibrational transitions provide important information on the physical and chemical structures of the above environments.... | rotational and high-resolution infrared spectrum of hc3n: global ro-vibrational analysis and improved line catalog for astrophysical observations |
we emphasize that the completeness of the partition function, that is, the use of a converged partition function at the typical temperature range of the survey, is very important to decrease the uncertainty on this quantity and thus to derive reliable interstellar molecular densities. in that context, we show how the u... | impact of nonconvergence and various approximations of the partition function on the molecular column densities in the interstellar medium |
the next generation gravitational waves (gw) detectors are most sensitive to gw emitted by compact (neutron star/black hole) binary mergers. if one of those is a neutron star the merger will also emit electromagnetic radiation via three possible channels: gamma-ray bursts and their (possibly orphan) afterglows, li-pacz... | radio flares of compact binary mergers: the effect of non-trivial outflow geometry |
interferometric radio astronomy data require the effects of limited coverage in the fourier plane to be accounted for via a deconvolution process. for the last 40 years this process, known as `cleaning', has been performed almost exclusively on all stokes parameters individually as if they were independent scalar image... | an improved method for polarimetric image restoration in interferometry |
this paper describes digital radio astronomical receivers used for decameter and meter wavelength observations. since 1998, digital receivers performing on-the-fly dynamic spectrum calculations or waveform data recording without data loss have been used at the utr-2 radio telescope, the uran vlbi system, and the gurt n... | digital receivers for low-frequency radio telescopes utr-2, uran, gurt |
sagittarius a* (sgr a*)-the supermassive black hole (smbh) in the center of our galaxy-has been observed in most of the electromagnetic spectrum, from radio to x-rays. diffuse γ-ray emission has been observed around sgr a* and a γ-ray point source has been detected coinciding with the smbh's position, although there is... | fermi-lat observations of sagittarius a*: imaging analysis |
the frequency agile solar radiotelescope (fasr) is a radio spectroscopic imager addressing all of solar science. it has been strongly endorsed as a top community priority by both astronomy & astrophysics decadal surveys and solar & space physics decadal surveys in the past two decades. the community must seize ... | frequency agile solar radiotelescope |
we present a detailed characterization of the population of compact radio-continuum sources in w51 a using subarcsecond very large array and atacama large millimeter/submillimeter array observations. we analyze their 2 cm continuum, the recombination lines (rls) h77α and h30α, and the lines of ${{\rm{h}}}_{2}\mathrm{co... | recombination lines and molecular gas from hypercompact h ii regions in w51 a |
the number of active and non active satellites in earth orbit has dramatically increased in recent decades, requiring the development of novel surveillance techniques to monitor and track them. in this paper, we build upon previous non-coherent passive radar space surveillance demonstrations undertaken using the murchi... | the development of non-coherent passive radar techniques for space situational awareness with the murchison widefield array |
we present observations of 12c32s, 12c34s, 13c32s, and 12c33s j = 2-1 lines toward a large sample of massive star-forming regions by using the arizona radio observatory 12 m telescope and the iram 30 m. taking new measurements of the carbon 12c/13c ratio, the 32s/34s isotope ratio was determined from the integrated 13c... | galactic interstellar sulfur isotopes: a radial 32s/34s gradient? |
as several large single-dish radio surveys begin operation within the coming decade, a wealth of radio data will become available and provide a new window to the universe. in order to fully exploit the potential of these datasets, it is important to understand the systematic effects associated with the instrument and t... | hide & seek: end-to-end packages to simulate and process radio survey data |
we produce the first low to mid-frequency radio simulation that incorporates both traditional extragalactic radio sources as well as synchrotron cosmic web emission. the filaments & galactic radio (figaro) simulation includes 10 unique 4° × 4° fields, incorporating active galactic nucleii (agns), star-forming galax... | figaro simulation: filaments & galactic radio simulation |
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