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maunakea is one of the world's primary sites for astronomical observing, with multiple telescopes operating over submillimeter to optical wavelengths. with its summit higher than 4200 m above sea level, maunakea is an ideal location for astronomy, with a historically dry, stable climate and minimal turbulence above the... | climate change and astronomy: a look at long-term trends on maunakea |
the astronomical applications greatly benefit from the knowledge of the instrument psf. we describe the psf reconstruction algorithm developed for the lbt luci instrument assisted by the soul scao module. the reconstruction procedure considers only synchronous wavefront sensor telemetry data and a few asynchronous cali... | brute, psf reconstruction for the soul pyramid-based single conjugate adaptive optics facility of the lbt |
an n -element interferometer measures correlations among pairs of array elements. closure invariants associated with closed loops among array elements are immune to multiplicative, element-based ("local") corruptions that occur in these measurements. till recently, it has been unclear how a complete set of independent ... | invariants in copolar interferometry: an abelian gauge theory |
the early and complete temporal characterization of optical, fast, transient sources requires continuous and multiband observations over different timescales (hours to months). for time-domain astronomy, using several telescopes to analyze single objects is the usual method, allowing the acquisition of highly sampled l... | muphoten: a multi-band photometry tool for telescope network |
non-maxwellian κ electron energy distributions (eeds) have been proposed in recent years to resolve the so-called "electron temperature and abundance discrepancy problem" in the study of planetary nebulae (pns). thus the need to develop diagnostic tools to determine from observations the eed of pns is raised. arising f... | the ultraviolet c ii lines as a diagnostic of κ-distributed electrons in planetary nebulae |
we obtained an optical spectrum (range 390-860 nm) of sn 2018lkg (= master ot j070634.76+635056.9), discovered by master (see atel 12345), on 2019-01-01.6528 ut with the xinglong 2.16-m telescope (+bfosc) of national astronomical observatories of china (naoc). | xinglong 2.16-m telescope spectroscopic classification of sn 2018lkg as a type iin supernova |
the sodium monoxide radical (nao) is observed in night-glow in the earth's mesosphere and likely has astronomical importance. this study concerns the optical transitions within the ground x 2π state and to the very low-lying (te ≈ 2000 cm-1) excited a 2σ+ state. a line list consisting of rovibronic term values, allowed... | exomol molecular line lists - xliii. rovibronic transitions corresponding to the close-lying x 2π and a 2σ+ states of nao |
the ubvri ccd photometric data of open star cluster ngc 1513 are obtained with the 3.6-m indo-belgian devasthal optical telescope (dot). analyses of the gaia edr3 astrometric data have identified 106 possible cluster members. the mean proper motion of the cluster is estimated as μαcosδ =1.29 ±0.02 and μδ=-3.74 ±0.02 ma... | optical observations of star clusters ngc 1513 and ngc 4147; white dwarf wd 1145+017 and k band imaging of star-forming region sh 2-61 with the 3.6-m devasthal optical telescope |
the stellar cataclysms producing astronomical transients have long been modeled as either a point-like explosion or jet-like engine ignited at the center of a spherically symmetric star. however, many stars are observed, or are expected on theoretical grounds, not to be precisely spherically symmetric, but rather to ha... | ellipsars: ring-like explosions from flattened stars |
binary stars are a very important source of astronomical information. those short-period binaries observed by means of both spectroscopy and interferometry can provide, through their corresponding orbits, precise values regarding individual masses as well as orbital parallaxes. for this reason, it is fundamental to att... | the most probable 3d orbit for spectroscopic binaries |
context. cutting-edge, ground-based astronomical instruments are fed by adaptive optics (ao) systems that are aimed at providing high performance down to the visible wavelength domain on 10 m class telescopes and in the near infrared for the first generation instruments of extremely large telescopes (elts). both applic... | super-resolution wavefront reconstruction |
the metrology of membrane structures, especially inflatable, curved, optical surfaces, remains challenging. internal pressure, mechanical membrane properties, and circumferential boundary conditions imbue highly dynamic slopes to the final optic surface. here, we present our method and experimental results for measurin... | surface measurement of a large inflatable reflector in cryogenic vacuum |
in optical wavelengths, the light emitted by comets consists of sunlight, reflected by dust, and the emission features of atoms and molecules. in his paper from 1957, l. haser develops the mathematical framework to describe the density distribution of cometary comas. when comet scientists refer to the haser model, they... | intensity distribution in the heads of comets |
results of a four-month campaign of astronomical seeing measurements at maidanak astronomical observatory (mao) are presented. a differential image motion monitor (dimm) was used for seeing estimations during the period from august to november 2018. the observation was organized within the framework of a site testing f... | astronomical seeing at maidanak observatory during the year 2018 |
we present the design and performance verification of a fiber-fed fourier transform spectrograph (fts) for spectroscopy in the optical band with the ability to reach a maximum optical path difference of 15 mm and allowing for an adjustable spectral resolution (λ / δλ) between 1 and 15,000. the designed fts system was s... | design and laboratory performance of a fiber-fed fourier transform spectrograph based on off-the-shelf components for astronomical medium and high-resolution spectroscopy |
context. high resolution spectroscopy at high signal-to-noise ratios (s/ns) is one the key techniques of the quantitative study of the atmospheres of extrasolar planets. observations at near-infrared wavelengths with fiber-fed spectrographs coupled to extremely large telescopes are particularly important to tackle the ... | experimental characterization of modal noise in multimode fibers for astronomical spectrometers |
the wide field infrared survey telescope (wfirst) coronagraph instrument (cgi) will be the first high-performance stellar coronagraph using active wavefront control for deep starlight suppression in space, providing unprecedented levels of contrast and spatial resolution for astronomical observations in the optical. on... | the wfirst coronagraph instrument: a major step in the exploration of sun-like planetary systems via direct imaging |
we report new branching fraction measurements for 199 uv and optical transitions of hf ii. these transitions range in wavelength (wavenumber) from 2068 to 6584 å (48,322-15,183 cm-1) and originate in 17 odd-parity upper levels ranging in energy from 38,578 to 53,227 cm-1. the branching fractions are combined with radia... | improved atomic transition probabilities for uv and optical lines of hf ii and determination of the hf abundance in two metal-poor stars |
the productivity of lick observatory (lo) is reviewed over the years from 1965 to 2019, a 55 yr period which commences with the shane 3 m telescope being the second-largest astronomical reflector in the world, but transitions into the era of 10 m ground-based optical telescopes. the metric of productivity used here is ... | research output between 1965 and 2019 from the use of telescopes at lick observatory |
the debris disc around hd 172555 was recently imaged in near-infrared polarized scattered light by the very large telescope's spectro-polarimetric high-contrast exoplanet research instrument. here we present optical aperture polarization measurements of hd 172555 by the high precision polarimetric instrument (hippi), a... | polarimetric and radiative transfer modelling of hd 172555 |
high sensitivity imaging at the level of single photons is an invaluable tool in many areas, ranging from microscopy to astronomy. however, development of single-photon sensitive detectors with high spatial resolution is very non-trivial. here we employ the single-pixel imaging approach and demonstrate a proof-of-princ... | single-pixel camera with a large-area microstrip superconducting single photon detector on a multimode fiber |
cosmic microwave background (cmb) b-modes detection is the main focus of future cmb experiments because of the valuable information it contains, particularly to probe the physics of the very early universe. for this reason, we have developed an optimized polarimeter demonstrator sensitive to the 10–20 ghz band in which... | optimization of a microwave polarimeter for astronomy with optical correlation and detection |
ultracool dwarfs (ucds) encompass a wide variety of compact stellar-like objects with spectra classified as late-m, l, t, and y. most of them have been discovered using wide-field imaging surveys. the virtual observatory (vo) has proven to be of great utility to efficiently exploit these astronomical resources. we aim ... | ultracool dwarfs in deep extragalactic surveys using the virtual observatory: alhambra and cosmos |
we present rest-frame optical spectra of 12 "nitrogen-loud" quasars at z 2.2, whose rest-frame ultraviolet (uv) spectra show strong nitrogen broad emission lines. to investigate their narrow-line region (nlr) metallicities, we measure the equivalent width (ew) of the [o iii]λ5007 emission line: if the nlr metallicity i... | chemical enrichment and accretion of nitrogen-loud quasars |
earth-like civilizations generate heat from the energy that they utilize. the thermal radiation from this heat can be a thermodynamic marker for civilizations. here we model such planetary radiation on earth-like planets and propose a strategy for detecting such an alienunintentionalthermodynamic electromagnetic biomar... | global warming as a detectable thermodynamic marker of earth-like extrasolar civilizations: the case for a telescope like colossus |
a small number of anomalously bright boulders on the near-earth rubble-pile asteroid (101955) bennu were recently identified as eucritic material originating from asteroid (4) vesta. building on this discovery, we explored the global presence of exogenic boulders on bennu. our analysis focused on boulders larger than 1... | characterization of exogenic boulders on the near-earth asteroid (101955) bennu from osiris-rex color images |
we present the local volume complete cluster survey (lovoccs; we pronounce it as "low-vox" or "law-vox," with stress on the second syllable), an nsf's national optical-infrared astronomy research laboratory survey program that uses the dark energy camera to map the dark matter distribution and galaxy population in 107 ... | lovoccs. i. survey introduction, data processing pipeline, and early science results |
in light of the newly opened and rapidly growing gravitational waves window in multi-messenger astronomy, in order to fully take advantage of the new opportunities we are provided with, new ideas are required for a better and deeper employ of the state-of-the-art probes we handle. following this goal, here we suggest a... | high accuracy on h0 constraints from gravitational wave lensing events |
optical sparse aperture (osa) systems show great potential for the next generation astronomical telescope system due to its excellent high resolution with low volume and weight. however, the sparse arrangement causes its mid-frequency modulation transfer function to be lower compared with a single fully-filled aperture... | image restoration of optical sparse aperture systems based on a dual target network |
context. earth's atmosphere imprints a large number of telluric absorption and emission lines on astronomical spectra, especially in the near infrared, that need to be removed before analysing the affected wavelength regions.aims: these lines are typically removed by comparison to a- or b-type stars used as telluric st... | modelling telluric line spectra in the optical and infrared with an application to vlt/x-shooter spectra |
context. this observational paper has been prepared in the context of the large multi-wavelength effort by many observers with the aim of following up the transient flaring event of v404 cygni that took place for several weeks in 2015 june.aims: our main original aim was to contribute to the study of this transient sou... | multi-colour optical photometry of v404 cygni in outburst |
aims: we present a study of the be/x-ray binary system v 0332+53 with the main goal of characterizing its behaviour mainly during the intermediate-luminosity x-ray event in 2008. in addition, we aim to contribute to the understanding of the behaviour of the donor companion by including optical data from our dedicated c... | activity from the be/x-ray binary system v0332+53 during its intermediate-luminosity outburst in 2008 |
context. an essential step to understanding protoplanetary evolution is the study of disks that contain gaps or inner holes. the pre-transitional disk around the herbig star hd 169142 exhibits multi-gap disk structure, differentiated gas and dust distribution, planet candidates, and near-infrared fading in the past dec... | a study of dust properties in the inner sub-au region of the herbig ae star hd 169142 with vlti/pionier |
the recent “planet nine” hypothesis has led to many observational and archival searches for this giant planet proposed to orbit the sun at hundreds of astronomical units. while trans-neptunian object searches are typically conducted in the optical, models suggest planet nine could be self-luminous and potentially brigh... | a 3π search for planet nine at 3.4 μm with wise and neowise |
we present results from laboratory detector characterizations of the first kilopixel bug arrays for the high- resolution wideband camera plus (hawc+) which is the imaging far-infrared polarimeter camera for the stratospheric observatory for infrared astronomy (sofia). our tests demonstrate that the array performance is... | performance of backshort-under-grid kilopixel tes arrays for hawc+ |
nasa cosmic origins (cor) program identified the development of high reflectivity mirror coatings for large astronomical telescopes particularly for the far ultra violet (fuv) part of the spectrum as a key technology requiring significant materials research and process development. in this paper we describe the challen... | aluminum mirror coatings for uvoir telescope optics including the far uv |
observations of the sun as a star have been key to guiding models of stellar atmospheres and additionally provide useful insights on the effects of granulation and stellar activity on radial velocity measurements. most high-resolution solar atlases contain telluric lines that span the optical and limit the spectral reg... | the iag solar flux atlas: telluric correction with a semiempirical model |
we introduce the swift/uvot+manga (swim) value-added catalog, which comprises 150 galaxies that have both sloan digital sky survey (sdss)/manga integral field spectroscopy and archival swift/uvot near-uv (nuv) images. the similar angular resolution between the three swift/uvot nuv images and the manga maps allows for a... | swift/uvot+manga (swim) value-added catalog |
earth-based gravitational-wave detectors will be limited by quantum noise in a large part of their spectrum. the most promising technique to achieve a broadband reduction of such noise is the injection of a frequency-dependent squeezed vacuum state from the output port of the detector, with the squeeze angle rotated by... | measurement of optical losses in a high-finesse 300 m filter cavity for broadband quantum noise reduction in gravitational-wave detectors |
a new generation of telescopes with mirror diameters of 20 m or more, called extremely large telescopes (elts) has the potential to provide unprecedented imaging and spectroscopy of exo-planetary systems, if the difficulties in achieving the extremely high dynamic range required to differentiate the planetary signal fr... | statistical framework for the utilization of simultaneous pupil plane and focal plane telemetry for exoplanet imaging i accounting for aberrations in multiple planes |
context. the evolution of massive stars surviving the red supergiant (rsg) stage remains unexplored due to the rarity of such objects. the yellow hypergiants (yhgs) appear to be the warm counterparts of post-rsg classes located near the humphreys-davidson upper luminosity limit, which are characterized by atmospheric i... | monitoring luminous yellow massive stars in m 33: new yellow hypergiant candidates |
we studied the dissociation reactions of electron impact on water vapor for several fragment species at optical and near-ultraviolet wavelengths (200-850 nm). the resulting spectrum is dominated by the hydrogen balmer series, by the oh (a 2σ+ - x 2π) band, and by the emission of ionic h2o+(a 2a1 - x 2b1) and oh+(a 3π -... | diagnostics of collisions between electrons and water molecules in near-ultraviolet and visible wavelengths |
we introduce a new generic archetype technique for source classification and identification, based on the np-complete set cover problem (scp) in computer science and operations research (or). we have developed a new heuristic scp solver, by combining the greedy algorithm and the lagrangian relaxation (lr) approximation... | a new view of classification in astronomy with the archetype technique: an astronomical case of the np-complete set cover problem |
we have conducted an imaging survey with the hubble space telescope wide field camera 3 (wfc3) of 70 galactic cepheids, typically within 1 kpc, with the aim of finding resolved physical companions. the wfc3 field typically covers the 0.1 pc area where companions are expected. in this paper, we identify 39 cepheids havi... | hubble space telescope snapshot survey for resolved companions of galactic cepheids |
a fully automatic remote telescope and dome control system has been installed at the university of athens observatory (uoao) in august 2012. it was constructed in the laboratory of astronomy and applied optics of the department and incorporated the already existing automation for observations and data gathering techniq... | the robotic and remotely controlled telescope at the university of athens observatory |
the large binocular telescope interferometer (lbti) combines the light from the two 8.4 m primary mirrors of the lbt for interferometry and adaptive optics (ao) imaging. with two high performance, state-of-the-art ao systems and adaptive secondary mirrors, a cryogenic instrument, and an edge-to-edge baseline of 23 m, t... | overview and prospects of the lbti beyond the completed hosts survey |
we consider the radiation properties and processes of a gas with a population inversion using the formalism based on the maxwell-bloch equations. we focus on the maser action and dicke's superradiance to establish their relationship in the overall radiation process during the temporal evolution of the system as a funct... | astronomical masers and dicke's superradiance |
infrared space interferometers can surpass the spatial resolution limitations of single-dish space telescopes. however, stellar interferometers from space have not been realized because of technical difficulties. two beams coming from individual satellites separated by more than a few tens of meters should precisely in... | high spatial resolution spectral imaging method for space interferometers and its application to formation flying small satellites |
cometary activity may be driven by ices with very low sublimation temperatures, such as carbon monoxide ice, which can sublimate at distances well beyond 20 au. this point is emphasized by the discovery of the oort cloud comet c/2014 un271 (bernardinelli-bernstein) and its observed activity out to ~26 au. through obser... | a look at outbursts of comet c/2014 un271 (bernardinelli-bernstein) near 20 au |
we present the result of the infrared medium-deep survey (ims) z ~ 6 quasar survey, using the combination of the ims near-infrared images and the canada-france-hawaii telescope legacy survey optical images. the traditional color selection method results in 25 quasar candidates over 86 deg2. we introduce the corrected a... | the infrared medium-deep survey. ix. discovery of two new z 6 quasars and space density down to m 1450 -23.5 mag |
in the context of adaptive optics for astronomy, one can rely on the statistics of the turbulent phase to assess a part of the system's performance. temporal statistics with one source and spatial statistics with two sources are well-known and are widely used for classical adaptive optics systems. a more general framew... | spatiotemporal statistics of the turbulent piston-removed phase and zernike coefficients for two distinct beams |
galaxy morphology is a long-standing subfield of astronomy, moving from visual qualifications to quantitative morphometrics. this book covers the descriptions developed by astronomers to describe the appearance of galaxies, primarily in optical, ultraviolet and near-infrared wavelengths. these descriptions range from g... | galaxy morphology |
as telescopes become larger, into the era of ∼40 m extremely large telescopes, the high-resolution vertical profile of the optical turbulence strength is critical for the validation, optimization and operation of optical systems. the velocity of atmospheric optical turbulence is an important parameter for several appli... | turbulence velocity profiling for high sensitivity and vertical-resolution atmospheric characterization with stereo-scidar |
carbon contamination induced by ultraviolet (uv) radiation affects precision optics in applications as diverse as semiconductor lithography and satellite observations of the sun. our previous experiments have shown that low-intensity uv-induced surface contamination depends quasilogarithmically on the partial pressure ... | extreme-ultraviolet-induced carbon growth at contaminant pressures between 10−10 and 10−6 mbar: experiment and model |
the first generation solar adaptive optics (ao) system, which consists of a fine tracking loop with a tip-tilt mirror (ttm) and a correlation tracker, and a high-order correction loop with a 37-element deformable mirror (dm), a correlating shack-hartmann (sh) wavefront sensor (wfs) based on the absolute difference algo... | first generation solar adaptive optics system for 1-m new vacuum solar telescope at fuxian solar observatory |
arduino microcontrollers are becoming increasingly popular in the physics/astronomy community. these devices can provide more in-depth labs on mechanics, electricity and magnetism, light and optics, etc., in addition to programming. these devices can be readily utilized to reach more non-physics/astronomy majors and un... | using arduino uno microcontroller to create interest in physics |
the goal of the present study is twofold. first, we employ new hst/stis spectra and photoionization modeling techniques to determine the progenitor masses of eight planetary nebulae (ic 2165, ic 3568, ngc 2440, ngc 3242, ngc 5315, ngc 5882, ngc 7662, and pb 6). second, for the first time we are able to compare each obj... | co-spatial long-slit uv/optical spectra of ten galactic planetary nebulae with hst/stis. ii. nebular models, central star properties, and he+cno synthesis |
ccd photometry of the recurrent nova rs oph has been performed with the 50/70 cm schmidt telescope of the rozhen national astronomical observatory (bulgaria) and the 41 cm telescope at the observatory of the university of jaen (spain) on 2021 september 2, october 4 and october 7. we have not detected flickering on minu... | rs oph - disappearance of the optical flickering |
the zwicky transient facility camera (ztfc) is a key element of the ztf observing system, the integrated system of optoelectromechanical instrumentation tasked to acquire the wide-field, high-cadence time-domain astronomical data at the heart of the zwicky transient facility. the ztfc consists of a compact cryostat wit... | the zwicky transient facility camera |
poppy (physical optics propagation in python) simulates physical optical propagation including diffraction. it implements a flexible framework for modeling fraunhofer and fresnel diffraction and point spread function formation, particularly in the context of astronomical telescopes. poppy provides the optical modeling ... | poppy: physical optics propagation in python |
telluric absorption lines impact the measuring of precise radial velocities (rvs) from high-resolution ground-based spectrographs. in this paper, we simulate the dependence of this impact on stellar spectral type and extend the work of the first paper in this series, which studied a g-type star, to a synthetic m-dwarf ... | characterizing and mitigating telluric absorption in precise radial velocities. ii. a study of an m2-type star |
the solar upper transition region imager (sutri) focuses on the solar transition region to achieve dynamic imaging observation of the upper transition region. in this paper, we report the optical system design, mechanical design, ultrasmooth mirror manufacture and measurement, euv multilayer film coating, prelaunch ins... | design, fabrication and assembly of the solar upper transition region imager (sutri) |
this paper focuses on point-spread function (psf) estimation for astronomical images containing only single extended objects captured by adaptive optics systems. the problem is very different from, and much more challenging than, psf estimation with point-like source images. we propose a new psf estimation framework ba... | point-spread function estimation for adaptive optics imaging of astronomical extended objects |
the astronomical light optical hybrid analysis project investigates the combined use of a telescope array interferometer and nonlinear optics to propose a new generation of instruments dedicated to high-resolution imaging for infrared astronomy. the nonlinear process of optical frequency conversion transfers the astron... | first on-sky fringes with an up-conversion interferometer tested on a telescope array |
optical wide-field surveys with a high cadence are expected to create a new field of astronomy, so-called “movie astronomy,” in the near future. the amount of data from the observations will be huge, and hence efficient data compression will be indispensable. here we propose a low-rank matrix approximation with sparse ... | data compression for the tomo-e gozen using low-rank matrix approximation |
nowadays more than two billion people own smartphones, without necessarily realizing they have a mobile physics lab that can be used to study acoustics, mechanics, astronomy, optics, fluids mechanics, or even serves as an oscilloscope. all smartphones have at least one camera, which is probably the most well-known and ... | studying ray optics with a smartphone |
the astrochemical importance of polycyclic aromatic hydrocarbons (pahs) is widespread, and a complete understanding of these pahs' photophysical and photochemical properties is of great interest to the astronomical community. the absorption of interstellar radiation by these molecules initiate various physical and chem... | electronic structure and ultrafast fragmentation dynamics of polycyclic aromatic hydrocarbons |
in this paper we describe the fitspec code, a data mining tool for the automatic fitting of synthetic stellar spectra. the program uses a database of 27,000 cmfgen models of stellar atmospheres arranged in a six-dimensional (6d) space, where each dimension corresponds to one model parameter. from these models a library... | fitspec: a new algorithm for the automated fit of synthetic stellar spectra for ob stars |
wave retarders having spatially varying optical axes orientations, called q-plates are extremely efficient devices for converting spin to orbital angular momentum of light and for the generation of optical vortices. most often, these plates are designed for a specific wavelength and have a homogeneous constant retardan... | wavelength-adaptable effective q-plates with passively tunable retardance |
since galileo's first observations in 1609, telescopes have grown dramatically in size. larger telescopes collect more light, allowing astronomers to detect fainter sources and to look further back in time towards the birth of the universe. the angular resolution of these telescopes, however, has been limited by turbul... | adaptive optics in astronomy |
we obtained an optical spectrum (range 360-860 nm) of master ot j081506.13+381123.3 (see atel #9971), discovered by master robotic net, on ut jan.20.6 2017 with the 2.16-m telescope (+bfosc) at xinglong station of national astronomical observatories of china (naoc). | spectroscopic classification of master ot j081506.13+381123.3 as a type ia supernova |
we report spatially resolved (fwhm ∼ 3.″8-4.″6) mid-ir imaging observations of the planetary nebula (pn) ngc 7027 taken with the 2.5 m telescope on board the stratospheric observatory for infrared astronomy (sofia). images of ngc 7027 were acquired at 6.3, 6.6, 11.1, 19.7, 24.2, 33.6, and 37.1 μ {{m}} using the faint o... | evidence from sofia imaging of polycyclic aromatic hydrocarbon formation along a recent outflow in ngc 7027 |
we report an optical spectrum (range 350-900 nm) of at 2016g that was obtained on ut jan. 10.6 2015 with the 2.4-m telescope (+yfosc) at the gaomeigu station of yunnan astronomical observatories of china. | spectroscopic classification of at 2016g as a broadlined type ic supernova |
aims: in the context of the future developments of long baseline interferometry at visible wavelengths, we have built a prototype instrument called fibered spectrally resolved interferometer - new design (friend) based on single mode fibers and a new generation detector called electron multiplying charge-coupled device... | fibered visible interferometry and adaptive optics: friend at chara |
the european extremely large telescope will see first lights by the end of 2024. with a diameter of almost 40 meters, it will be the biggest optical telescope ever built from the ground. the elt will open a brand new window in a sensitivity / spatial angular resolution parameter space. to take the full benefit of the s... | overview of the european extremely large telescope and its instrument suite |
context. gaseous and dust debris disks around white dwarfs (wds) are formed from tidally disrupted planetary bodies. this offers an opportunity to determine the composition of exoplanetary material by measuring element abundances in the accreting wd's atmosphere. a more direct way to do this is through spectral analysi... | the gaseous debris disk of the white dwarf sdss j1228+1040. hst/cos search for far-ultraviolet signatures |
we report on high-resolution spectroscopy of the 2009.0 spectroscopic event of η carinae collected via smarts observations using the ctio 1.5 m telescope and echelle spectrograph. our observations were made almost every night over a two-month interval around the photometric minimum of η car associated with the periastr... | the optical wind line variability of η carinae during the 2009.0 event |
current imaging atmospheric cherenkov telescopes for very high energy γ-ray astrophysics are pointing instruments with a field of view up to a few tens of sq deg. we propose to build an array of two non-steerable (drift) telescopes. each of the telescopes would have a camera with a fov of 5 × 60 sq deg oriented along t... | machete: a transit imaging atmospheric cherenkov telescope to survey half of the very high energy γ-ray sky |
we present new high-resolution (∼ 0\buildrel{\prime\prime}\over{.} 09) h-band imaging observations of the circumstellar disk around the t tauri star su aur. our observations with subaru-hiciao have revealed the presence of scattered light as close as 0.″ 15 (∼20 au) to the star. within our image, we identify bright emi... | near-ir high-resolution imaging polarimetry of the su aur disk: clues for tidal tails? |
we report a discovery of six massive galaxies with both extremely large lyα equivalent widths (ews) and evolved stellar populations at z ∼ 3. these massive extremely strong lyα emitting objects (maestlos) have been discovered in our large-volume systematic survey for strong lyα emitters (laes) with 12 optical intermedi... | discovery of massive, mostly star formation quenched galaxies with extremely large lyα equivalent widths at z ∼ 3 |
context. modern space telescopes are currently providing high-precision light curves for a large fraction of the sky, such that many new variable stars are being discovered. however, some stars have periodic variability with periods on the order of minutes and require high-cadence photometry to probe the physical mecha... | adaptive elliptical aperture photometry: a software package for high-cadence ground-based photometry. i. application to rapid oscillators observed from saao |
adaptive optics systems are an essential technology for the modern astronomy for ground-based telescopes. one of the most recent revolution in the field is the introduction of the pyramid wavefront sensor. the higher performance of this device is paid with increased complexity in the control. in this work, we report ab... | advances in control of a pyramid single conjugate adaptive optics system |
we have derived elemental abundances of a remarkable star, hd 179821, with unusual composition (e.g. [na/fe] = 1.0 ± 0.2 dex) and extra-ordinary spectral characteristics. its metallicity at [fe/h] = 0.4 dex places it among the most metal-rich stars yet analysed. the abundance analysis of this luminous star is based on ... | hd 179821 (v1427 aql, iras 19114+0002) - a massive post-red supergiant star? |
optical turbulence in the enclosure of a ground-based telescope can be a major contributor to the total optical turbulence strength and can therefore limit the precision of astronomical observations, in terms of angular resolution, or signal to noise ratio, depending on the instrumentation used. here we propose a new d... | line-of-sight optical dome turbulence monitor |
in practical applications, it is often crucial to track high-speed rotating objects. however, the traditional fourier transform techniques are not applicable under such circumstances because the fourier spectrum of a rotating object is changing. here, we propose a laguerre-gaussian (lg) transform to analyze the rotatin... | laguerre-gaussian transform for rotating image processing |
the origin of the gamma-ray burst (grb) x-ray plateau, especially the internal plateau, is still unclear, but it could be related to a grb's magnetar central engine. it is generally believed that the spin-down power of the magnetar is injected into forward external shock; however, we propose here that most of the power... | to power the x-ray plateaus of gamma-ray bursts through larger amplitude electromagnetic waves |
next generation astronomical optics will enable science discoveries across all fields and impact the way we perceive the universe in which we live. to build these systems, optical metrology tools have been developed that push the boundary of what is possible. we present a summary of a few key metrology technologies tha... | emerging technology for astronomical optics metrology |
our team at the inaf-astronomical observatory of padova and the university of padova is engaged in the design, construction and operations of instruments with very high time accuracy in the optical band for applications to high time resolution astrophysics and quantum astronomy. two instruments were built to perform ph... | (very) fast astronomical photometry for meter-class telescopes |
light pollution poses a growing threat to optical astronomy, in addition to its detrimental impacts on the natural environment, the intangible heritage of humankind related to the contemplation of the starry sky and, potentially, on human health. the computation of maps showing the spatial distribution of several light... | fast fourier-transform calculation of artificial night sky brightness maps |
nova eruptions, thermonuclear explosions on the surfaces of white dwarfs (wds), are now recognized to be among the most common shock-powered astrophysical transients. we present the early discovery and rapid ultraviolet (uv), optical, and infrared (ir) temporal development of at 2019qyl, a recent nova in the nearby scu... | at 2019qyl in ngc 300: internal collisions in the early outflow from a very fast nova in a symbiotic binary |
context. precise photometric and astrometric measurements on astronomical images require an accurate knowledge of the point spread function (psf). when the psf cannot be modelled directly from the image, psf-reconstruction techniques become the only viable solution. so far, however, their performance on real observatio... | successful application of psf-r techniques to the case of the globular cluster ngc 6121 (m 4) |
we report the detection of an optical impact flash on jupiter on 2021 october 15 by a dedicated telescope, planetary observation camera for optical transient surveys, for the first time. our temporally resolved three-band observations of the flash allowed investigations of its optical energy without the need for approx... | detection of an extremely large impact flash on jupiter by high-cadence multiwavelength observations |
the detection of emission lines associated with accretion processes is a direct method for studying how and where gas giant planets form, how young planets interact with their natal protoplanetary disk, and how volatile delivery to their atmosphere takes place. hα (λ = 0.656 μm) is expected to be the strongest accretio... | magao-x and hst high-contrast imaging of the as209 disk at hα |
theoretical predictions of the population of galactic symbiotic stars (systs) are highly inconsistent with the current known population. despite intense effort over the past decades, observations are still far below the predictions. the majority of known systs so far are identified based on selection criteria establish... | where are the missing symbiotic stars? uncovering hidden symbiotic stars in public catalogues |
the rapid imaging planetary spectrograph (rips) was designed as a long-slit high-resolution spectrograph for the specific application of studying atmospheres of spatially extended solar system bodies. with heritage in terrestrial airglow instruments, rips uses an echelle grating and order-sorting filter to obtain optic... | rapid imaging planetary spectrograph |
transient sources such as supernovae (sne) and tidal disruption events are candidates of high-energy neutrino sources. however, sne commonly occur in the universe and a chance coincidence of their detection with a neutrino signal cannot be avoided, which may lead to a challenge of claiming their association with neutri... | identifying high-energy neutrino transients by neutrino multiplet-triggered follow-ups |
adaptive optics normally concerns the feedback correction of phase aberrations. such correction has been of benefit in various optical systems, with applications ranging in scale from astronomical telescopes to super-resolution microscopes. here we extend this powerful tool into the vectorial domain, encompassing highe... | vectorial adaptive optics |
in this paper, we report a search for vanishing sources in poss i red images using virtual observatory (vo) archives, tools, and services. the search, conducted in the framework of the vasco project, aims at finding poss i (red) sources not present in recent catalogues like pan-starrs dr2 (limiting magnitude r = 21.4) ... | discovering vanishing objects in poss i red images using the virtual observatory |
an observatory class national large optical-ir telescope (nlot), is proposed to be built and located in the country. the telescope consists of a 10-12 m segmented primary. in order to cater to a diversity of observational programs, the telescope is designed with high throughput in both the optical and ir regions (0.3-5... | a 10-m class national large optical-ir telescope |
we investigate the accretion disk for a sort of regular black holes which are characterized by sub-planckian curvature and minkowskian core. we derive null geodesics outside the horizon of such regular black holes and analyze the feature of the light rays from the accretion disk which can be classified into direct emis... | accretion disk for regular black holes with sub-planckian curvature |
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