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li2o-(2-3x)mgo-(x)al2o3-p2o5 (lmap) (x = 0.00-0.08) ceramic system was prepared through solid state synthesis route at different sintering temperatures (800-925 °c). a small addition of al2o3 (x = 0.02) in lmap ceramics lowers the sintering temperature by more than 100 °c with good relative density of 94.13%. the sinte... | synthesis and characterisation of novel low temperature ceramic and its implementation as substrate in dual segment cdra |
the results of a study of h2o and oh maser emission in the complex region of active star formation w75 n are presented. observations were obtained using the 22-m radio telescope of the pushchino radio astronomy observatory (russia) and the nan3ay radio telescope (france). flaring h2o maser features may be identified wi... | evolution of the h2o and oh maser emission in w75 n |
we report a design solution for a highly reliable, low-noise and extremely efficient cryogenically cooled transmit/receive unit for a large antenna system meant for radio-astronomical observations and deep-space communications in the x band. we describe our design solution and the results of a series of laboratory and ... | cryogenically cooled low-noise amplifier for radio-astronomical observations and centimeter-wave deep-space communications systems |
high synchrotron peak (hsp; ${\nu }_{\mathrm{sy}}^{\mathrm{pk}}\gt {10}^{15}$ hz) bl lac objects are some of the most extreme accelerators in the universe. those found at high redshifts (z > 1) challenge our understanding of blazar evolution models and are crucial for cosmological measurements of the extragalactic b... | nustar observations and multiwavelength modeling of the high-redshift bl lacertae object 4fgl j2146.5-1344 |
we have compiled a new multiwavelength spectral energy distribution (sed) for the closest obscured low-ionization emission-line region active galactic nucleus (agn), ngc 4736, also known as m94. the sed comprises mainly high-resolution (mostly sub-arcsecond, or, at the distance to m94, ≲23 pc from the nucleus) observat... | a jet-dominated model for a broad-band spectral energy distribution of the nearby low-luminosity active galactic nucleus in m94 |
phased array feed (paf) receivers are at the forefront of modern day radio astronomy. pafs are currently being developed for spectral line and radio continuum surveys and to search for pulsars and fast radio bursts. here, we present results of the pilot survey for pulsars and fast radio bursts using the focal plane l-b... | a 21 cm pilot survey for pulsars and transients using the focal l-band array for the green bank telescope |
basing our analysis on rogue i, a catalog of over 32,000 radio sources associated with optical galaxies, we provide two diagnostics to select the galaxies where the radio emission is dominated by an active galactic nucleus (agn), referred to in the paper as radio-agns. each of these diagnostics can be applied independe... | identifying radio-active galactic nuclei among radio-emitting galaxies |
the radio spectra of main-sequence stars remain largely unconstrained due to the lack of observational data to inform stellar atmosphere models. as such, the dominant emission mechanisms at long wavelengths, how they vary with spectral type, and how much they contribute to the expected brightness at a given radio wavel... | the first radio spectrum of a rapidly rotating a-type star |
with this research note, we are releasing the carma-nro orion survey data first presented in kong et al., enhanced with additional coverage of the l1641-c region to the south of the integral-shaped filament. we are including position-position-velocity cubes for the molecular lines 12co(1-0), 13co(1-0), and c18o(1-0). t... | the carma-nro orion survey—data release |
advances in astronomy are intimately linked to advances in digital signal processing (dsp). this special issue is focused upon advances in dsp within radio astronomy. the trend within that community is to use off-the-shelf digital hardware where possible and leverage advances in high performance computing. in particula... | introduction to the special issue on digital signal processing in radio astronomy |
new detections of radio emission from the geminga pulsar at three low radio frequencies are presented. the observations were carried out at 42-112 mhz on two sensitive transit radio telescopes of the pushchino radio astronomy observatory. three new digital receivers were used to detect the pulses and obtain dynamical s... | the geminga radio pulsar. new low-frequency results |
the fits (flexible image transport system) data format was developed in the late 1970s for storage and exchange of astronomy-related image data. since then, it has become a standard file format not only for images, but also for radio interferometer data (e.g. uvfits, fits-idi). but is fits the right format for next-gen... | is hdf5 a good format to replace uvfits? |
shanghai astronomical observatory has upgraded its difx cluster to 420 cpu cores and a 432-tb storage system at the end of 2014. an international network connection for the raw data transfer has also been established. the routine operations for ivs sessions including crf, aov, and apsg series began in early 2015. in ad... | current status of shanghai vlbi correlator |
the tens of millions of radio sources to be detected with next-generation surveys pose new challenges, quite apart from the obvious ones of processing speed and data volumes. for example, existing algorithms are inadequate for source extraction or cross-matching radio and optical/ir sources, and a new generation of alg... | astroinformatics challenges from next-generation radio continuum surveys |
this chapter focuses on approaches to real-time stream processing when computation is spread over multiple boards. one of the major challenges with digital systems in radio astronomy is dealing with the huge data volumes generated by digitization of wide-bandwidth signals from multiple receivers. massive data rates are... | real-time stream processing in radio astronomy |
we report the likely gev γ-ray emission from the composite supernova remnant (snr) comp g327.1+1.1 by analyzing ∼12.2 yr of the fermi large area telescope (fermi-lat) pass 8 data. we found the features of its spectrum and luminosity are well consistent with those of the observed comp snrs in the milky way. moreover, th... | likely detection of gev gamma-ray emission from the composite supernova remnant comp g327.1+1.1 with fermi-lat |
radio, millimeter, and sub-millimeter astronomy experiments as well as remote sensing applications often require castable absorbers with well known electromagnetic properties to design and realize calibration targets. in this context, we fabricated and characterized two samples using different ratios of two easily comm... | permittivity and permeability of epoxy-magnetite powder composites at microwave frequencies |
dynamic modification of the pattern of a reflector antenna system traditionally requires an array of feeds. this paper presents an alternative approach in which the scattering from a fraction of the reflector around the rim is passively modified using, for example, an electronically-reconfigurable reflectarray. this fa... | sidelobe modification for reflector antennas by electronically reconfigurable rim scattering |
we present the first detailed polarimetric studies of cygnus a at 230 ghz with the submillimeter array (sma) to constrain the mass accretion rate onto its supermassive black hole. we detected the polarized emission associated with the core at a fractional polarization of $0.73\pm 0.15 \% $ . this low fractional polariz... | constraints on the mass accretion rate onto the supermassive black hole of cygnus a using the submillimeter array |
aims: in this work, we aim to achieve the first laboratory detection of acetohydroxamic acid (ch3conhoh), a relevant glycine isomer, to enable its eventual identification in the ism.methods: we employed a battery of state-of-the-art rotational spectroscopic techniques in the time domain to measure the microwave spectru... | laboratory detection and astronomical study of interstellar acetohydroxamic acid, a glycine isomer |
the nonthermal filament (ntf) radio structures clustered within a few hundred parsecs of the galactic center (gc) are apparently unique to this region of the galaxy. recent radio images of the gc using meerkat at 1 ghz have revealed a multitude of faint, previously unknown ntf bundles (ntfbs), some of which are compris... | a very large array study of newly discovered southern latitude nonthermal filaments in the galactic center: radio continuum total-intensity and spectral index properties |
esa's international gamma-ray astrophysics laboratory (integral) was launched on 17 oct 2002 at 06:41 cest. since then, it has been providing long, uninterrupted observations (up to about 47 hr, or 170 ksec, per satellite orbit of 2.7 days) with a large field-of-view (fully coded: 100 deg^2), msec time resolution, kev ... | integral reloaded: spacecraft, instruments and ground system |
correlation for radio interferometer array applications, including very long baseline interferometry (vlbi), is a multidisciplinary field that traditionally involves astronomy, geodesy, signal processing, and electronic design. in recent years, however, high-performance computing has been taking over electronic design,... | model-based performance characterization of software correlators for radio interferometer arrays |
a pilot project has been proceeded to map $1 \textrm{deg}^2$ on the galactic plane for radio recombination lines (rrls) using the five-hundred-metre aperture spherical telescope (fast). the motivation is to verify the techniques and reliabilities for a large-scale galactic plane rrl survey with fast aiming to investiga... | baseline correction for fast radio recombination lines: a modified penalised least squares smoothing technique |
nobeyama 45m radio telescope (nro45m) is a large single-dish radio telescope that has been operating for more than 35 years. the data processing pipeline for nro45m (nro pipeline) is developed recently as an extension of the single-dish pipeline for the atacama large millimeter/submillimeter array (alma). the nro pipel... | pipeline calibration and imaging for the nobeyama 45m radio telescope |
superconducting flux-flow-oscillators (ffos) based on unidirectional flow of magnetic vortices in a single-long josephson junction (jj) and operating at 4.2 k are key elements of sub-terahertz integrated-receivers used in radio-astronomy and atmospheric science. here, we report on the development of sub-terahertz ffos ... | magnetic flux quantum periodicity of the frequency of the on-chip detectable electromagnetic radiation from superconducting flux-flow-oscillators |
a dual beam, dual polarization, low noise receiver has been installed at a cassegrain focus of the nasa 70m antenna near canberra, australia. it operates in five pairs of 1ghz bands from 17 to 27ghz simultaneously. the receiver temperature measured at the feed is 21-22k at 22ghz and, during dry winter night-time condit... | the 17-27 ghz dual horn receiver on the nasa 70 m canberra antenna |
the thermal expansion of radio telescopes has been recognized as a significant systematic error in very long baseline interferometry (vlbi) data analysis. although the thermal expansion model recommended by international earth rotation service (iers) conventions 2010 can achieve millimeter accuracy for the internationa... | investigations of thermal deformation based on the monitoring system of tianma 13.2 m vgos telescope |
ragavi is a python based tool that generates self-contained interactive plots of calibration solutions and visibilities. it has two aspects which perform these tasks, namely ragavi-gains and ragavi-vis respectively. ragavi-gains provides interactivity by displaying useful identification information for each data point ... | ragavi: a radio astronomy gains and visibilities inspector |
ice nucleating particle (inp) measurements were made at two high-altitude stations in india. aerosols collected on filter paper at girawali observatory, inter university center for astronomy & astrophysics (igo), and at the radio astronomy center, ooty (rac), were activated in deposition mode using a thermal gradie... | multiyear observations of deposition-mode ice nucleating particles at two high-altitude stations in india |
the raw outputs of a radio interferometer, i.e. the complex visibility data and all associated metadata, while of little interest to the end-user astronomer per se, contain a wealth of information about the functioning of the instrument and software pipelines, and can provide vital diagnostics during the entire data re... | shadems: rapid plotting of big radio interferometry data |
we present pure rotational transitions of the rare iron monoxide isotopologues. ? , ? and ? in their lowest spin states ? . for ? , the rotational spectrum reveals hyperfine splitting due to the nuclear spin of ? . we use dunham-like parameters to analyse the new laboratory data together with data from the literature. ... | rotational spectroscopy of rare iron monoxide isotopologues: a mass-independent analysis |
this paper proposes, and practically implements, a technique for finding equivalent frequencies, which are attributed to the atmospheric optical depths measured by a two-channel wideband radiometric system in the millimeter wavelength range. establishment of the equivalent frequency (averaged over the frequency respons... | consistent determination of the integral humidity and effective optical depth of the atmosphere in the millimeter wavelength range using wideband radiometers |
our report presents the results of the experimental dependence of the ionospheric scintillations intensity of cosmic radio sources on their position in the visible celestial hemisphere. the results refer to the mean geographical latitudes and decameter range of radio waves. the intensity of ionospheric scintillations i... | dependence of the ionospheric scintillations intensity of cosmic radio sources on their position in the sky |
high-mass stars have masses greater than 8 solar masses and are the main source of heavy elements such as iron in the interstellar medium. this type of stars form in giant molecular clouds. studying the molecular environment in star-forming regions is crucial to understand the physical structure and conditions that lea... | survey for c-band high spectral lines with the arecibo telescope |
space debris are human-made objects, of variable sizes and shapes, that orbit the earth or reenter the atmosphere. they represent a serious problem for every active spacecraft and satellite, due to the high risk of collision and consequently the generation of new debris. one of the main segments of the space situationa... | status of the sardinia radio telescope as a receiver of the biralet radar for space debris observations |
we introduce a new imaging method for radio interferometry based on sparse- modeling. the direct observables in radio interferometry are visibilities, which are fourier transformation of an astronomical image on the sky-plane, and incomplete sampling of visibilities in the spatial frequency domain results in an under-d... | imaging black holes with sparse modeling |
machine learning techniques have proven to be increasingly useful in astronomical applications over the last few years, for example in object classification, estimating redshifts and data mining. one example of object classification is classifying galaxy morphology. this is a tedious task to do manually, especially as ... | galaxy classifications with deep learning |
we investigate the effectiveness of the statistical radio frequency interference (rfi) mitigation technique spectral kurtosis ( $\widehat{{sk}}$ ) in the face of simulated realistic rfi signals. $\widehat{{sk}}\,$ estimates the kurtosis of a collection of m power values in a single channel and provides a detection metr... | simulating spectral kurtosis mitigation against realistic radio frequency interference signals |
this book introduces the five-hundred-meter aperture spherical radio telescope (fast), also known as the "the sky eye", one of the china's big science facilities. using easy-to-understand language, the book covers the scientific background, construction process, achievements, and effects of fast on the development of t... | the sky eye: five-hundred-meter aperture spherical radio telescope (fast) |
the 197 radio astronomy dishes of the square kilometre array (ska) in south africa, due for completion later this decade, may find itself threatened from above by tens of thousands of communications satellites beaming down radio signals. the rocket company spacex has already launched hundreds of starlink satellites, th... | satellite swarm threatens radio array |
jupiter's decimeter-wavelength flux density is dominated by synchrotron emission from magnetically trapped ~5-50 mev electrons in the radiation belts. synchrotron radio emission remains the most useful diagnostic of the radiation belts, and a global picture is provided by ground-based observations. monitoring of the lo... | variability of jupiter's synchrotron radiation: goldstone apple valley radio telescope (gavrt) observations -ii |
traditional walsh technique is used to eliminate cross-talk in a array of radio telescope where achieving synchronization between modulator and demodulator without compromising sensitivity is a real challenge. the paper describes a novel approach named walsh delay hunting (wdh) to synchronize independently running modu... | reducing effects of cross-talk in a radio telescope using walsh modulation |
high speed data transfer and high performance imaging can be realized by using radio waves in high frequency bands, such as millimeter waves and thz waves, where wide frequency bands are available. however, the cell size would be smaller than a few hundred meters, due to large free space propagation loss and large atmo... | terahertz and photonics seamless short distance links for future mobile networks |
tunka-rex, the tunka radio extension at the taiga facility (tunka advanced instrument for cosmic ray physics and gamma astronomy) in siberia, has recently been expanded to a total number of 63 salla antennas, most of them distributed on an area of one square kilometer. in the first years of operation, tunka-rex was sol... | tunka-rex: status, plans, and recent results |
signal channelization enables efficient frequency domain processing and is a mainstay of astronomical signal processing, but applications that require high time resolution necessitate reconstruction of the original wide band signal. in a previous paper, a near-perfect method of reconstructing a time-limited input signa... | performance of oversampled polyphase filterbank inversion via fourier transform: continuous signals |
the casa team is working to design and prototype the next generation of common astronomy software applications (casa) for radio interferometry data reduction. the next generation casa technology stack invests heavily in python-based frameworks for parallelization and data manipulation, including dask and xarray, along ... | casa next generation infrastructure |
in recent years, there have been an increasing concern in the world regarding the impact of technology on the development prospects of astronomical observations from the earth's surface and near-earth space, which was called the dark and quiet sky problem. there are three categories of artificial interference negativel... | satellite mega-constellations and the dark and quiet sky problem |
china plans to establish a lunar orbital vlbi (very long baseline interferometer) station around 2025, which will carry a space passive hydrogen maser as the time and frequency reference. since it is the first time to use a space passive hydrogen maser for vlbi observation, its feasibility needs to be studied and verif... | the experiment and analysis on vlbi observations of space passive hydrogen maser |
we investigate the impact of anomalous microwave emission (ame) on the radio-millimeter spectral energy distribution for three typical interstellar medium (ism) conditions surrounding star-forming regions-cold neutral medium, warm neutral medium, and photodissociation regions-by comparing the emissivities of three majo... | spinning nanoparticles impacted by c-shock: implications for radio-millimeter emission from star-forming regions |
in this paper, we reported the measured results of the antenna efficiency, sensitivity, and system noise temperature of the tm65m radio telescope. the key parameters describing a radio astronomy receiving system were introduced at first. then, we discussed the measurement methods and the measuring errors. finally, the ... | antenna performance measurements at l, s, c, and x bands for the tm65m radio telescope |
the uncertainties in meteor radar data and the problem of hyperbolic meteors are interconnected. meteor orbital data, obtained by the meteor automatic radar system (mars) at the kharkiv institute of radio electronics, ukraine, was used to develop the algorithm to determine the uncertainties of the orbital elements obta... | uncertainties in mars meteor orbit radar data |
five-hundred-meter aperture spherical radio telescope (fast) is the most sensitive single-dish telescope in the world. in the past few years since it was put into use, there have been some relatively important scientific research achievements in the fields of pulsars and fast radio bursts (frb). in the future, there ma... | development of key technologies of the radio astronomy phased array feed digital backend |
alto is a concept/project in the exploratory phase since 2013 aiming to build a wide-field vhe gamma-ray observatory at very high altitude in the southern hemisphere. the operation of such an observatory will complement the northern hemisphere observations performed by hawc and will make possible the exploration of the... | very-high-energy gamma-ray astronomy with the alto observatory |
probabilistic cross-identification has been successfully applied to a number of problems in astronomy from matching simple point sources to associating stars with unknown proper motions and even radio observations with realistic morphology. here we study the bayes factor for clustered objects and focus in particular on... | probabilistic cross-identification of galaxies with realistic clustering |
we selected 90 massive star-forming clumps with strong n2h+(1-0), hco+(1-0), hcn(1-0), and hnc(1-0) emission from the millimetre astronomy legacy team 90 ghz survey. we obtained herschel data for all 90 sources and nrao vla sky survey data for 51 of them. we convolved and regridded all images to the same resolution and... | spatial variation of the chemical properties of massive star-forming clumps |
vlbi measurements of the absolute proper motions of 23 radio stars have been collected from published data. these are stars with maser emission, or very young stars, or asymptotic-giant-branch stars. by comparing these measurements with the stellar proper motions from the optical catalogs of the hipparcos celestial ref... | residual hcrf rotation relative to the inertial coordinate system |
we present simultaneous 22 and 43 ghz observations of the microquasar cyg x-3 during a series of small-scale flaring activity in a hard state. in the end of january 2016, cyg x-3 was in a state transition from a soft to hard state after a minimum hard x-ray flux at 15-50 kev. we have observed cyg x-3 in 3-6 february im... | spectral inversion of 43 to 22 ghz during small flares in a hard state of cyg x-3 in february 2016 |
the taiga observatory addresses ground-based gamma-ray astronomy at energies from a few tev to several pev, as well as cosmic ray physics from 100 tev to several eev . taiga will be located in the tunka valley, ~ 50 km west from lake baikal. the different detectors of the taiga will be grouped in 6 arrays to measure ch... | taiga experiment: present status and perspectives |
building a 3d picture of the universe at any distance is one of the major challenges in astronomy, from the nearby solar system to distant quasars and galaxies. this goal has forced astronomers to develop techniques to estimate or to measure the distance of point sources on the sky. while most distance estimates used s... | modern geometric methods of distance determination |
in order to satisfy the research needs of nanshan 25 m radio telescope of xinjiang astronomical observatory (xao) and study the key technology of the planned qitai radio telescope (qtt), the receiver group of xao studied the gpu (graphics processing unit) based real-time frb searching algorithm which developed from the... | the research and test of fast radio burst real-time search algorithm based on gpu acceleration |
to celebrate the tenth anniversary since the launch of fermi gamma-ray space telescope, we take a retrospect to a series of breakthroughs fermi has contributed to pulsar astronomy in the last decade. apart from significantly enlarging the population of γ-ray pulsars, observations with the large area telescope onboard f... | a golden decade of gamma-ray pulsar astronomy |
modern scientific research particularly radio astronomical spectroscopic observations cannot be imagined without appropriate software suite. that is necessary for two reasons: 1) data are in digital form and 2) data processing is a complex multi-step process. in this paper created in virac data processing suite for a s... | virac maser data processing suite |
low frequency radio astronomy in tasmania began with the arrival of grote reber to the state in 1954. after analysing ionospheric data from around the world, he concluded that tasmania would be a very suitable place to carry out low frequency observations. communications with graeme ellis in tasmania, who had spent sev... | the history of early low frequency radio astronomy in australia. 3: ellis, reber and the cambridge field station near hobart |
context. the active star-forming region w33b is a source of oh and h2o maser emission located in distinct zones around the central object.aims: the aim was to obtain the complete stokes pattern of polarised oh maser emission and to trace its variability and to investigate flares and long-term variability of the h2o mas... | oh and h2o maser variations in w33b |
this work sketches a possible design architecture of a low-frequency radio interferometer located on the lunar surface. the design has evolved from single antenna experiments aimed at the global signal detection of the epoch of reionization (eor) to the square kilometre array (ska) which, when complete, will be capable... | low-frequency technology for a lunar interferometer |
the 2007 discovery of fast radio bursts (frbs), bright and millisecond-duration astronomical radio pulses, presented to the astronomical community a tantalizing opportunity into the transient universe. understanding the origins, mechanisms and applications of frbs is currently one of the most rapidly evolving sub-field... | fast helps push the study of fast radio bursts into statistical regimes |
enhancing interoperable data access to radio data has become a science priority within the international virtual observatory alliance (ivoa). this lead to the foundation of the ivoa radio astronomy interest group. several radio astronomers and project scientists enrolled in various projects (nrao, askap, lofar, jive, a... | radio astronomy visibility data discovery and access using ivoa standards |
the results of observations of oh (λ = 18 cm) and h2o (λ = 1.35 cm) masers toward as 501 obtained with the nançay observatory radio telescope (france) and the 22-m radio telescope of the pushchino radio astronomy observatory (russia), respectively, are presented. nine cycles of h2o maser activity ranging from 2.8 to 6.... | variability of the oh and h2o maser emission toward as 501 |
the atacama large millimeter/sub-millimeter array (alma) is currently the largest (sub-)mm wave telescope in the world and will be used for astronomical observations in all atmospheric windows from 35 to 950 ghz when completed. the alma band 1 (35-50 ghz) receiver will be used for the longest wavelength observations wi... | alma band 1 optics (35-50 ghz): tolerance analysis, effect of cryostat infrared filters and cold beam measurements |
in the present paper, recent measurement results of refurbished irbene rt-16 radio telescope receiving system performance are presented. the aim of the research is to evaluate characteristics of rt-16, which will allow carrying out necessary amplitude calibration in both single dish and vlbi observations, to improve th... | performance evaluation of irbene rt-16 radio telescope receiving system |
in radio astronomy instrumentation, the benefit of increased spectral grasp must be evaluated against a decrease in overall system performance (e.g., system noise, stability, and optical efficiency) and considerable effort has gone into quantifying the best overall choice to define receiver bands for a particular teles... | octave bandwidth receiver technology for radio and millimetre-wave telescopes |
radio frequency interference (rfi) has plagued radio astronomy which potentially might be as bad or worse by the time the square kilometre array (ska) comes up. rfi can be either internal (generated by instruments) or external that originates from intentional or unintentional radio emission generated by man. with the h... | radio frequency interference detection using machine learning. |
an analysis of observations obtained over 26 years beginning in 1992 have indicated the appearance of sinusoidal variations with a period of about 12 years in the residual deviations of the pulse arrival times (pats) for the pulsar psr b0943+10. this behavior in the pat residuals could be due to the influence of a plan... | a 12-year periodicity in the pulse arrival times for the pulsar psr b0943+10 |
radio telescopes are a scarce resource designed to provide experimental data for astrophysical research, and various studies have focused on the design of observing schedules that make optimal use of available telescope time. we consider strategies for minimising the time required to observe a fixed set of pulsars, whi... | dispatch approaches for scheduling radio telescope observations |
we present results from pulsar observations using the giant metrewave radio telescope (gmrt) as a phased array with infield phasing. the antennas were kept in phase throughout the observation by applying antenna based phase corrections derived from visibilities that were obtained in parallel with the phased array beam ... | phased array observations with infield phasing |
kliko is a docker-based container specification for running one or multiple related compute jobs. the key concepts of kliko are the encapsulation of data processing software into a container and the formalization of the input, output and task parameters. by formalizing the parameters, the software is represented as abs... | kliko-the scientific compute container format |
in radio interferometry, the quantization process introduces a bias in the magnitude and phase of the measured correlations which translates into errors in the measurement of source brightness and position in the sky, affecting both the system calibration and image reconstruction. in this paper, we investigate the bias... | quantization bias for digital correlators |
we present high-resolution (0.″17 × 0.″14) atacama large millimeter/submillimeter array (alma) observations of the co (6-5) line and 435 μm dust continuum emission within a ∼9″ × 9″ area centered on the nucleus of the galaxy ngc 5135. ngc 5135 is a well-studied luminous infrared galaxy that also harbors a compton-thick... | alma observation of ngc 5135: the circumnuclear co (6-5) and dust continuum emission at 45 pc resolution |
context. galactic all-sky maps at very disparate frequencies, such as in the radio and γ-ray regime, show similar morphological structures. this mutual information reflects the imprint of the various physical components of the interstellar medium.aims: we want to use multifrequency all-sky observations to test resoluti... | sharpening up galactic all-sky maps with complementary data. a machine learning approach |
master-saao robotic telescope (global master-net: http://observ.pereplet.ru, lipunov et al., 2010, advances in astronomy, vol. 2010, 30l) located in south africa (south african astronomical observatory) was pointed to the frb 181228a ( ferah et al., atel #12335 ) 17723 sec after trigger time at 2018-12-28 18:44:13 ut, ... | master psn discovery during frb181228 error line inspection |
spectral polarization observations of radio sources above sunspots are regularly carried out with the ratan-600 radio telescope (ratan is a russian acronym for the radio astronomical telescope of the academy of sciences). the in-depth studies of the spectra reveal new effects. in this paper, we analyze the manifestatio... | on detecting the fourth gyrofrequency harmonic in microwave emission spectra above sunspots |
the mid-infrared instrument (miri) extends the reach of the james webb space telescope (jwst) to 28.5 μm. it provides subarcsecond-resolution imaging, high sensitivity coronagraphy, and spectroscopy at resolutions of λ/δλ ~ 100-3500, with the high-resolution mode employing an integral field unit to provide spatial data... | the mid-infrared instrument for jwst and its in-flight performance |
leveraging the unrivalled performance of optical clocks as key tools for geo-science, for astronomy and for fundamental physics beyond the standard model requires comparing the frequency of distant optical clocks faithfully. here, we report on the comparison and agreement of two strontium optical clocks at an uncertain... | a clock network for geodesy and fundamental science |
context. sky surveys produce enormous quantities of data on extensive regions of the sky. the easiest way to access this information is through catalogues of standardised data products. xmm-newton has been surveying the sky in the x-ray, ultra-violet, and optical bands for 20 years.aims: the xmm-newton survey science c... | the xmm-newton serendipitous survey. ix. the fourth xmm-newton serendipitous source catalogue |
we present an overview of the national science foundation's daniel k. inouye solar telescope (dkist), its instruments, and support facilities. the 4 m aperture dkist provides the highest-resolution observations of the sun ever achieved. the large aperture of dkist combined with state-of-the-art instrumentation provide ... | the daniel k. inouye solar telescope - observatory overview |
within the last decade, optical atomic clocks have surpassed the best cesium clocks, which are used to realize the unit of time and frequency, in terms of accuracy and stability by about two orders of magnitude. when remote optical atomic clocks are connected by links without degradation in the clock signals, an optica... | optical clock networks |
the problem of imaging through thick scattering media is encountered in many disciplines of science, ranging from mesoscopic physics to astronomy. photons become diffusive after propagating through a scattering medium with an optical thickness of over 10 times the scattering mean free path. as a result, no image but on... | learning-based lensless imaging through optically thick scattering media |
optical microcombs represent a new paradigm for generating laser frequency combs based on compact chip-scale devices, which have underpinned many modern technological advances for both fundamental science and industrial applications. along with the surge in activity related to optical microcombs in the past decade, the... | applications of optical microcombs |
optical spectrometry is a tool to investigate wavelength-dependent light-matter interactions and is widely used in astronomy, physics and chemistry. integration and miniaturization of the currently bulky spectrometers will have an impact on applications where compactness and low complexity are key, such as air- and spa... | an integrated broadband spectrometer on thin-film lithium niobate |
optical frequency combs, which emit pulses of light at discrete, equally spaced frequencies, are cornerstones of modern-day frequency metrology, precision spectroscopy, astronomical observations, ultrafast optics and quantum information1-7. chip-scale frequency combs, based on the kerr and raman nonlinearities in monol... | gate-tunable frequency combs in graphene-nitride microresonators |
the wave-particle duality of light introduces two fundamental problems to imaging, namely, the diffraction limit and the photon shot noise. quantum information theory can tackle them both in one holistic formalism: model the light as a quantum object, consider any quantum measurement, and pick the one that gives the be... | resolving starlight: a quantum perspective |
multispectral imaging plays an important role in many applications from astronomical imaging, earth observation to biomedical imaging. however, the current technologies are complex with multiple alignment-sensitive components, predetermined spatial and spectral parameters by manufactures. here, we demonstrate a single-... | single-shot multispectral imaging with a monochromatic camera |
the recent demonstration of dissipative kerr solitons in microresonators has opened a new pathway for the generation of ultrashort pulses and low-noise frequency combs with gigahertz to terahertz repetition rates, enabling applications in frequency metrology, astronomy, optical coherent communications, and laser-based ... | sub-milliwatt-level microresonator solitons with extended access range using an auxiliary laser |
we produce a set of 72 nir-through-uv extinction curves by combining new hubble space telescope/stis optical spectrophotometry with existing international ultraviolet explorer spectrophotometry (yielding gapless coverage from 1150 to 10000 å) and nir photometry. these curves are used to determine a new, internally cons... | an analysis of the shapes of interstellar extinction curves. vii. milky way spectrophotometric optical-through-ultraviolet extinction and its r-dependence |
tunable narrowband spectral filtering across arbitrary optical wavebands is highly desirable in a plethora of applications, from chemical sensing and hyperspectral imaging to infrared astronomy. yet, the ability to reconfigure the optical properties, with full reversibility, of a solid-state large-area narrowband filte... | reversible optical tuning of gesbte phase-change metasurface spectral filters for mid-wave infrared imaging |
we present the ancillary data and basic physical measurements for the galaxies in the alma large program to investigate c+ at early times (alpine) survey - the first large multiwavelength survey that aims at characterizing the gas and dust properties of 118 main-sequence galaxies at redshifts 4.4 < z < 5.9 via th... | the alpine-alma [c ii] survey: multiwavelength ancillary data and basic physical measurements |
astronomical roentgen telescope - x-ray concentrator (art-xc) is the hard x-ray instrument with grazing incidence imaging optics on board the spektr-roentgen-gamma (srg) observatory. the srg observatory is the flagship astrophysical mission of the russian federal space program, which was successively launched into orbi... | the art-xc telescope on board the srg observatory |
two new imaging instruments, `alopeke and zorro, were designed, built, and commissioned at the gemini-north and gemini-south telescopes in 2018 and 2019, respectively. here we describe them and present the results from over a year of operation. the two identical instruments are based on the legacy of the dssi (differen... | twin high-resolution, high-speed imagers for the gemini telescopes: instrument description and science verification results |
the generation of temporal cavity solitons in microresonators results in coherent low-noise optical frequency combs that are critical for applications in spectroscopy, astronomy, navigation or telecommunications. breather solitons also form an important part of many different classes of nonlinear wave systems, manifest... | breather soliton dynamics in microresonators |
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