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with rapid response capabilities, and a daily planning of its observing schedule, the neil gehrels swift observatory is ideal for monitoring transient and variable sources. here we present a sample of the 12 novae with the most detailed ultraviolet (uv) follow-up by swift—the first uniform analysis of such uv light-cur... | ultraviolet and x-ray light-curves of novae observed by the neil gehrels swift observatory |
the search for faint emission or absorption lines in astronomical spectra has received considerable attention in recent years, especially in the x-ray wavelength range. these features usually appear as a deficit or excess of counts in a single resolution element of the detector, and as such they are referred to as unre... | probability models of chance fluctuations in spectra of astronomical sources with applications to x-ray absorption lines |
the hard x-ray modulation telescope (hxmt) is a broad-band x-ray astronomical satellite from 1 to 250 kev. understanding the x-ray background in detail will help to achieve a good performance of the instrument. in this work, we make use of the mass modeling technique to estimate the background of high energy telescope ... | simulation of the in-flight background for hxmt/he |
we present dabs (database of accreting binary simulations), an open-access database of modelled low mass x-ray binaries (lmxbs). dabs has been created using evolutionary tracks of neutron star and black hole lmxbs, spanning a large set of initial conditions for the accretor mass, donor mass, and orbital period. the lmx... | low mass x-ray binary simulation data release |
as china's first x-ray astronomical satellite, insight-hxmt (hard x-ray modulation telescope) successfully launched on jun 15, 2017. it performs timing and spectral studies of bright sources to determine their physical parameters. hxmt carries three main payloads onboard: the high energy x-ray telescope (he, 20-250 kev... | in-orbit calibration status of the insight-hxmt |
shocks, turbulence, and winds all influence the electron velocity distribution in hot plasmas, exciting lower-energy electrons and generating a high-energy (typically power-law) tail. this effect, typically described as a κ distribution can affect both the line and continuum x-ray spectra emitted by the plasma. hahn &a... | x-ray spectra from plasmas with high-energy electrons: κ-distributions and e--e- bremsstrahlung |
from hubble space telescope/cosmic origins spectrograph spectra of five quasars, 16 outflows are detected. for 11 outflows, we are able to constrain their distances to the central source (r) and their energetics. in instances of multiple electron number density determinations (used in the calculation of r) for the same... | hst/cos observations of quasar outflows in the 500-1050 šrest frame. vii. distances and energetics for 11 outflows in five quasars |
open clusters are thought to be the birthplace of most stars in the galaxy. thus, they are excellent laboratories for investigating stellar evolution, and x-ray properties of various types of stars (including binary stars, evolved stars, and compact objects). in this work, we investigate the population of x-ray sources... | population of x-ray sources in the intermediate-age cluster ngc 3532: a test bed for machine-learning classification |
scanning sky monitor (ssm) onboard astrosat is an xray sky monitor in the soft x-ray band designed with a large field of view to detect and locate transient x-ray sources and alert the astronomical community about interesting phenomena in the x-ray sky. ssm comprises position sensitive proportional counters with 1d cod... | scanning sky monitor (ssm) onboard astrosat |
the pre-maximum evolution of a nova is the last frontier in studying such objects. yz reticuli 2020 is the only nova whose x-ray flash was detected. the x-ray flash occurs immediately after the onset of thermonuclear runaway, so its physical properties impose severe constraints on the nova model. we discuss what we can... | pre-maximum evolution of the classical nova yz reticuli |
a major source of background for x-ray focal plane detectors in space instrumentation aboard missions, such as extended roentgen survey with an imaging telescope array and athena wide field imager, is the space radiation environment. high-energy radiations from the environment interact with the spacecraft structure lea... | impact of impurities in shielding material on simulations of instrument background in space |
all-sky monitors can measure the fluxes of astrophysical sources by measuring the changes in observed counts as the source is occulted by the earth. such measurements have typically been carried out by all-sky monitors like cgro-batse and fermi-gbm. we demonstrate for the first time the application of this technique to... | using collimated czti as all-sky x-ray detector based on earth occultation technique |
arrays of position-sensitive virtual frisch-grid cdznte (czt) detectors offer an economical approach to making high efficiency and high energy resolution gamma cameras for spectroscopy and imaging of radioactive sources. there are many application areas for such instruments including gamma-rays astronomy, medical and i... | a 4 × 4 array module of position-sensitive virtual frisch-grid cdznte detectors for gamma-ray imaging spectrometers |
scanning sky monitor (ssm) onboard astrosat is an x-ray sky monitor in the energy range 2.5-10 kev. ssm scans the sky for x-ray transient sources in this energy range of interest. if an x-ray transient source is detected in outburst by ssm, the information will be provided to the astronomical community for follow-up ob... | study of x-ray transients with scanning sky monitor (ssm) onboard astrosat |
we report on the detection of the new x-ray outburst from the neutron star low-mass x-ray binary aql x-1 by leia (lobster eye imager for astronomy). the position of the leia source is r.a. = 287.801 deg, dec = -0.585 deg with an uncertainty of 1.7 arcmin (radius, 90%c.l. | leia observations of the outburst from aql x-1 |
circumstantial evidence suggests that magnetism and enhanced x-ray emission are likely correlated in early b-type stars: similar fractions of them ( 10%) are strong and hard x-ray sources and possess strong magnetic fields. it is also known that some b-type stars have spots on their surface. yet up to now no x-ray acti... | detection of magnetic field in the b2 star ρ ophiuchi a with eso fors2 |
compact x-rays detectors made of 1/2" or 1" :labr3:ce crystals of cubic shape with sipm array readout have been developed for the famu experiment at riken-ral. the aim is a precise measurement of the proton zemach radius with incoming muons. additional applications may be found in medical physics, such as pet, homeland... | large area labr3:ce crystals read by sipm arrays with improved timing and temperature gain drift control |
the x-ray soi pixel sensor onboard the force satellite will be placed in the low earth orbit and will consequently suffer from the radiation effects mainly caused by geomagnetically trapped cosmic-ray protons. based on previous studies on the effects of radiation on soi pixel sensors, the positive charges trapped in th... | radiation damage effects on double-soi pixel sensors for x-ray astronomy |
the advent of gravitational wave (gw) astronomy has provided us with observations of black holes more massive than those known from x-ray astronomy. however, the observation of an intermediate-mass black hole (imbh) remains a big challenge. after their second observing run, the ligo \& virgo scientific collaboratio... | nuria: numerical relativity injection analysis of spinning binary black hole signals in advanced ligo data |
the earth occultation technique has broad applications in both astronomy and atmospheric density measurements. we construct the background model during the occultation of the crab nebula observed by the insight-hard x-ray modulation telescope (insight-hxmt) at energies between 6 and 100 kev. we propose a bayesian atmos... | neutral atmospheric density measurement using insight-hxmt data by the earth occultation technique |
we look for simulated star-forming linear features such as the one recently discovered by van dokkum et al. in the cosmological hydrodynamical simulation astrid. among the runaway black holes in astrid, none are able to produce clear star-forming wakes. meanwhile, flyby encounters, typically involving a compact galaxy ... | flyby galaxy encounters with multiple black holes produce star-forming linear features |
neutrino interactions with stellar material are widely believed to be fundamental to the explosion of massive stars. however, this important process has remained difficult to confirm observationally. we propose a new method to verify it using x-ray observations of the supernova remnant cassiopeia a. the elemental compo... | examining neutrino-matter interactions in the cassiopeia a supernova |
we analyze three observations of grs 1915+105 in 2017 by insight-hard x-ray modulation telescope when the source was in a spectrally soft state. we find strong absorption lines from highly ionized iron, which are due to absorption by disk wind outflowing at a velocity of ~1000 km s-1 along our line of sight. two of the... | the disk wind in grs 1915+105 as seen by insight-hard x-ray modulation telescope |
in this chapter we present a brief summary of methods, instruments and calibration techniques used in modern astronomical polarimetry in the optical wavelengths. we describe the properties of various polarisation devices and detectors used for optical broadband, imaging and spectropolarimetry, and discuss their advanta... | optical polarimetry: methods, instruments and calibration techniques |
the cherenkov telescope array (cta) will be the next generation gamma-ray observatory and will be the major global instrument for very-high-energy astronomy over the next decade, offering 5 - 10 x better flux sensitivity than current generation gamma-ray telescopes. each telescope will provide a snapshot of gamma-ray i... | application of pattern spectra and convolutional neural networks to the analysis of simulated cherenkov telescope array data |
in this paper, we report on the development of a monolithic active pixel sensor for x-ray imaging using 0.2 µm fully depleted silicon-on-insulator (soi)-based technology to support next generation astronomical satellite missions. detail regarding low-noise dual-gain soi based pixels with a charge sensitive amplifier an... | a silicon-on-insulator-based dual-gain charge-sensitive pixel detector for low-noise x-ray imaging for future astronomical satellite missions |
the laue project, supported by the italian space agency (asi), is devoted to the development of a long focal length (even 20 m or longer) laue lens for gamma ray astronomy between 80 and 600 kev. these lenses take advantage of bragg diffraction to focus radiation onto a small spot drastically improving the signal to no... | a simulation study on the focal plane detector of the laue project |
we present new x-ray observations of the optically obscured protostar hl tau and the intermediate-mass herbig be star hd 100546. both objects are surrounded by spectacular disks showing complex morphology, including rings and gaps that may have been sculpted by protoplanets. hl tau was detected as a variable hard x-ray... | x-ray emission and disk irradiation of hl tau and hd 100546 |
nasa's chandra x-ray observatory has ushered in a revolution in x-ray astronomy. over the last two decades chandra has captured stunning celestial x-ray images, measured spectra and monitored light curves to reveal and map the hottest, most energetic regions of the universe. celebrating its 20th anniversary, this book ... | the chandra x-ray observatory; exploring the high energy universe |
artificial intelligence techniques like machine learning and deep learning are being increasingly used in astronomy to address the vast quantities of data, which are now widely available. we briefly introduce some of these techniques and then describe their use through the examples of star-galaxy classification and the... | machine learning in astronomy |
we present the design of tessim, a simulator for the physics of transition edge sensors developed in the framework of the athena end to end simulation effort. designed to represent the general behavior of transition edge sensors and to provide input for engineering and science studies for athena, tessim implements a nu... | tessim: a simulator for the athena-x-ifu |
3d printing, also called additive manufacturing, offers a new vision for optical fabrication in term of achievable optical quality and reduction of weight and cost. in this paper we describe two different ways to use this technique in the fabrication process. the first method makes use of 3d printing in the fabrication... | 3d printing for astronomical mirrors |
historical observations of transients are crucial for studies of their long-term evolution. this paper forms part of a series of papers in which we develop methods for the analysis of ancient data of transient events and their usability in modern science. prior research on this subject by other authors has focused on l... | counterparts of far eastern guest stars: novae, supernovae, or something else? |
in recent years, a number of purpose-built scintillator-based polarimeters have studied bright astronomical sources for the first time in the hard x-ray band (tens to hundreds of kev). the addition of polarimetry can help data interpretation by resolving model-dependent degeneracies. the typical instrument approach is ... | a compton polarimeter using scintillators read out with mppcs through citiroc asic |
we report on resolving power measurements of an x-ray reflection grating designed for use in an astronomical soft x-ray spectrograph. the grating was patterned via electron-beam lithography (ebl) to have fanned grooves to match the convergence of an illuminating beam. grating measurements were conducted in an echelle-l... | large-format x-ray reflection grating operated in an echelle-like mounting |
the solar dynamics observatory (sdo)/euv variability experiment (eve) provides rich information on the thermodynamic processes of solar activities, particularly on solar flares. here, we develop a method to construct thermodynamic spectrum (tds) charts based on the eve spectral lines. this tool could potentially be use... | thermodynamic spectrum of solar flares based on sdo/eve observations: techniques and first results |
micropore optics have recently been implemented in a lobster eye geometry as a compact x-ray telescope. fields generated by rare-earth magnets are used to reduce the flux of energetic electrons incident upon the focal plane detector in such a setup. we present the design and implementation of the electron diverters for... | design and implementation of electron diverters for lobster eye space-based x-ray optics |
resonance scattering (rs) is an important process in astronomical objects, because it affects measurements of elemental abundances and distorts surface brightness of the object. it is predicted that rs can occur in plasmas of supernova remnants (snrs). although several authors reported hints of rs in snrs, no strong ob... | evidence for resonance scattering in the x-ray grating spectrum of the supernova remnant n49 |
a series of gravitational instabilities in a circumnuclear gas disk (cnd) are required to trigger gas transport to a central supermassive black hole and ignite active galactic nuclei (agns). a test of this scenario is to investigate whether an enhanced molecular gas mass surface density (σmol) is found in the cnd-scale... | circumnuclear molecular gas in low-redshift quasars and matched star-forming galaxies |
hess j0632+057 is a gamma-ray binary composed of a compact object orbiting a be star with a period of about 315 days. extensive x-ray and tev gamma-ray observations have revealed a peculiar light curve containing two peaks, separated by a dip. we present the results of simultaneous observations in hard x-rays with nust... | probing the properties of the pulsar wind in the gamma-ray binary hess j0632+057 with nustar and veritas observations |
svom (space-based multi-band astronomical variable objects monitor) is a sino-french space mission dedicated to the study of gamma-ray bursts (grbs) in the next decade, capable to detect and localise the grb emission, and to follow its evolution in the high-energy and x-ray domains, and in the visible and nir bands. th... | scientific prospects for spectroscopy of the gamma-ray burst prompt emission with svom |
understanding star formation in resolved low mass systems requires the integration of information obtained from observations at different wavelengths. we have combined new and archival multi-wavelength observations on a set of 20 nearby starburst and post-starburst dwarf galaxies to create a data archive of calibrated,... | the panchromatic starburst irregular dwarf survey (starbirds): observations and data archive |
the jovian system is a treasure trove of x-ray sources: diverse and dynamic atmospheric and auroral emissions, diffuse radiation belt and io torus emissions, and plasma-surface interactions with jupiter's moons. the system is a rich natural laboratory for astronomical x-rays with each region showcasing its own x-ray pr... | x-ray emissions from the jovian system |
we present an analysis of the dispersed spectral data from 11 epochs (2011 march-2018 september) of supernova remnant (snr) 1987a observations performed with chandra. these observations were performed with the high energy transmission grating (hetg) as part of our ongoing chandra monitoring campaign of snr 1987a, whose... | high-cadence dispersed spectral analysis of supernova remnant 1987a |
labr3:ce crystals have been introduced for radiation imaging in medical physics, with photomultiplier or single sipm readout. an r&d was pursued with 1/2″ and 1″ labr3:ce crystals, from different producers, to realize compact large area detectors (up to some cm2 area) with sipm array readout, aiming at high light y... | online control of the gain drift with temperature of sipm arrays used for the readout of labr3:ce crystals |
context. xmm-newton provides unprecedented insight into the x-ray universe, recording variability information for hundreds of thousands of sources. manually searching for interesting patterns in light curves is impractical, requiring an automated data-mining approach for the characterization of sources.aims: straightfo... | exploring x-ray variability with unsupervised machine learning. i. self-organizing maps applied to xmm-newton data |
x-ray flares, lasting for ∼100-1000 s in the x-ray band, are often observed following gamma-ray bursts (grbs). the physical origin of x-ray flares is still unknown merely with the temporal/spectral information. on the other hand, some polarimeters are expected to be launched within several years, thanks to the increasi... | probing magnetic fields of grb x-ray flares with polarization observations |
high-resolution magnetic susceptibility and % caco3 records (5 to 10 cm sampling interval) are used to track astronomical cycles from a lower berriasian record from central tunisia. 622 samples were measured for magnetic susceptibility and carbonate content as paleoclimate proxies for the detection of potential milanko... | linking the variation of sediment accumulation rate to short term sea-level change using cyclostratigraphy: case study of the lower berriasian hemipelagic sediments in central tunisia (southern tethys) |
gamma-400 γ-ray telescope is designed to measure fluxes of γ-rays and the electron-positron cosmic ray component possibly generated in annihilation or decay of dark matter particles; to search for and study in detail discrete γ-ray sources, to examine the energy spectra of galactic and extragalactic diffuse γ-rays, to ... | space γ-observatory gamma-400 current status and perspectives |
in this paper we review the physics and performance of back-illuminated ccds. models of back-illuminated ccds are used to derive requirements for stable, strong surface passivation in space-relevant environments. models and data are used to compare state-of-the-art surface passivation methods with 2d-doped surfaces. mb... | 2d-doped silicon detectors for uv/optical/nir and x-ray astronomy |
the einstein probe (ep) mission is a science mission designed for the time domain astronomy, which is approved by the chinese academy of sciences (cas) in 2017 and is to be launched in 2023 with a duration time of more than 3 years. the follow-up x-ray telescope (fxt) is an important payload onboard ep, which employs t... | design and testing of the optics for fxt onboard ep satellite |
expected to launch in 2021 spring, the imaging x-ray polarimetry explorer (ixpe) is a nasa astrophysics small explorer mission with significant contributions from the italian space agency (asi). the ixpe observatory features three identical x-ray telescopes, each comprised of a 4-m-focal length mirror module assembly (... | ixpe mirror module assemblies |
the massive binary system, ? car, is a colliding wind binary with strong stellar winds that can reach hypersonic velocities up to 3000 km/s. with a high eccentricity of 0.9 and a period of 5.53 years the binary system passed periastron in february 2020. when the strong winds from the luminous blue variable component (?... | characterization of the colliding wind region in the superluminous massive ? carinae |
toward an era of x-ray astronomy, next-generation x-ray optics are indispensable. to meet a demand for telescopes lighter than the foil optics but with a better angular resolution <1 arcmin, we are developing micropore x-ray optics based on micromaching technologies. using sidewalls of micropores through a thin sili... | ultralightweight x-ray telescope missions: orbis and geo-x |
silicon photodiodes are very useful devices as x-ray beam monitors in synchrotron radiation beamlines, as well as other astronomy and space applications. owing to their lower susceptibility to variable temperature and illumination conditions, there is also special interest in silicon carbide devices for some of these a... | four-quadrant silicon and silicon carbide photodiodes for beam position monitor applications: electrical characterization and electron irradiation effects |
this paper is focused on recent progress in the development of broad-band multilayer coatings designed for hard x-ray energies, for use in future astronomical telescopes. we describe a new laboratory-based hard x-ray reflectometer for atwavelength characterization of multilayer films, we present the results of an exper... | advancements in hard x-ray multilayers for x-ray astronomy |
depfet active pixel sensors (aps) have been introduced as focal plane detectors for x-ray astronomy already in 1996. fabricated on high resistivity, fully depleted silicon and back-illuminated they can provide high quantum efficiency and low noise operation even at very high read rates. in 2009 a new type of depfet aps... | first results on depfet active pixel sensors fabricated in a cmos foundry—a promising approach for new detector development and scientific instrumentation |
we present the latest update and progress on the future japanese x-ray satellite mission diffuse intergalactic oxygen surveyor (dios). dios is proposed to jaxa as a small satellite mission, and would be launched with an epsilon rocket. dios would carry on the legacy of astro-h, which carries semiconductor-based microca... | future japanese x-ray tes calorimeter satellite: dios (diffuse intergalactic oxygen surveyor) |
the imaging x-ray polarimetry explorer (ixpe) will add polarization to the properties (time, energy, and position) observed in x-ray astronomy. a nasa astrophysics small explorer (smex) in partnership with the italian space agency (asi), ixpe will measure the 2-8-kev polarization of a few dozen sources during the first... | the imaging x-ray polarimetry explorer (ixpe): technical overview ii |
neutron stars cooling after sustained accretion outbursts provide unique information about the neutron star crust and underlying dense matter. comparisons between astronomical observations of these cooling transients and model calculations of neutron star crust cooling have frequently been used to constrain neutron sta... | crust-cooling models are insensitive to the crust-core transition pressure for realistic equations of state |
richardson-lucy (rl) deconvolution is one of the classical methods widely used in x-ray astronomy and other areas. amid recent progress in image processing, rl deconvolution still leaves much room for improvement under realistic situations. one direction is to include the positional dependence of a point-spread functio... | richardson-lucy deconvolution with a spatially variant point-spread function of chandra: supernova remnant cassiopeia a as an example |
unexpected structure in images of astronomical sources often presents itself upon visual inspection of the image, but such apparent structure may either correspond to true features in the source or be due to noise in the data. this paper presents a method for testing whether inferred structure in an image with poisson ... | detecting unspecified structure in low-count images |
prompted by x-ray detections from multiple surveys, we investigated the a-type star hd 63021 and found that it is a double-lined spectroscopic binary with highly variable emission associated with the primary star. analysis of our multiepoch spectroscopic observations, the majority of which were carried out on small-ape... | hd 63021: chromospheric activity and mass transfer in a close binary |
polarlight is a gas pixel x-ray polarimeter mounted on a cubesat, which was launched into a sun-synchronous orbit in 2018 october. we build a mass model of the whole cubesat with the geant4 toolkit to simulate the background induced by the cosmic x-ray background (cxb) and high-energy charged particles in the orbit. th... | modeling the in-orbit background of polarlight |
the spatial distribution of energetic protons contributes to the understanding of magnetospheric dynamics. based upon 17 yr of the cluster/rapid observations, we have derived machine-learning-based models to predict the proton intensities at energies from 28 to 962 kev in the 3d terrestrial magnetosphere at radial dist... | prediction of soft proton intensities in the near-earth space using machine learning |
electromagnetic observations of gravitational-wave and high-energy neutrino events are crucial in understanding the physics of their astrophysical sources. x-ray counterparts are especially useful in studying the physics of the jet, the energy of the outflow, and the particle acceleration mechanisms in the system. ultr... | swift follow-up observations of gravitational-wave and high-energy neutrino coincident signals |
the einstein probe (ep) satellite is designed for x-ray time-domain astronomy. the follow-up x-ray telescope (fxt) is one of the scientific payloads onboard ep. it will mainly be used for the follow-up x-ray observation, and it will also be used for the sky survey and target of opportunity (too) observation. the focal ... | design and performance of the focal plane camera for fxt onboard the einstein probe satellite |
it is important to map the large-scale matter distribution in the local universe for cosmological studies, such as the tracing of the large-scale peculiar velocity flow, the characterisation of the environment for different astronomical objects, and for precision measurements of cosmological parameters. we used x-ray l... | the cosmic large-scale structure in x-rays (classix) cluster survey. iv. superclusters in the local universe at z ≤ 0.03 |
aims: we present a multiwavelength study of the be/x-ray binary system xte j1946+274 with the main goal of better characterizing its behavior during x-ray quiescence. we also aim to shed light on the possible mechanisms which trigger the x-ray activity for this source.methods: xte j1946+274 was observed by chandra-acis... | detection of a large be circumstellar disk during x-ray quiescence of xte j1946+274 |
astrosat is india's first satellite fully devoted to astronomical observations covering a wide spectral band from optical to hard x-rays by a complement of 4 co-aligned instruments and a scanning sky x-ray monitor. one of the instruments is large area x-ray proportional counter with 3 identical detectors. in order to a... | performance of large area x-ray proportional counters in a balloon experiment |
yz ret is the first x-ray flash detected classical nova, and is also observed in optical, x-ray, and gamma-ray. we propose a comprehensive model that explains the observational properties. the white dwarf mass is determined to be ~1.33 m ☉, which reproduces the multiwavelength light curves of yz ret, from optical, x-ra... | a multiwavelength light-curve analysis of the classical nova yz ret: an extension of the universal decline law to the nebular phase |
we report the in-orbit performance of scanning sky monitor (ssm) onboard astrosat. the ssm operates in the energy range 2.5 to 10 kev and scans the sky to detect and locate transient x-ray sources. this information of any interesting phenomenon in the x-ray sky as observed by ssm is provided to the astronomical communi... | early in-orbit performance of scanning sky monitor onboard astrosat |
progress in the fabrication technology of normal incidence multilayer interference mirrors permits the traditional optical methods of microscopy, astronomy, and lithography to be transferred to the vacuum ultraviolet (vuv, wavelength: 10-200 nm) and the long-wavelength part of the soft x-ray (sxr, wavelength: 2-10 nm) ... | diffraction limited x-ray optics: technology, metrology, applications |
in order to achieve monochromatic x-rays of higher energy, and so as to calibrate the hard x-ray satellite-borne detectors and to test the energy response at high energy values, a hard x-ray test facility which is based on a single crystal monochromator was designed and built. the facility consists of four parts, namel... | the realization and study of (21-301) kev monochromatic x-rays |
the author formed his theory on black hole and white hole juxtapose in 2004 and was introduced to modern astronomical instrumentation and space telescopes by astronomy: exploring time and space. since the theory were built upon quantum physics, nuclear dynamics applied to cosmology, and special relativity in relation t... | research on the kerr-newman black hole in m82 confirms black hole and white hole thermonuclear binding |
the neil gehrels swift observatory has proven to be an extraordinary supernova (sn) observatory. the clearest application of swift's unique strengths is obtaining very early uv and x-ray data of young sne, which enables robust constraints on their progenitor systems. as part of a year-long swift guest investigator key ... | a swift response to newly discovered, nearby transients |
the fermi large area telescope (fermi-lat) 3fhl catalog is the latest catalog of >10 gev sources and will remain an important resource for the high-energy community for the foreseeable future. therefore, it is crucial that this catalog is made complete by providing associations for most sources. in this paper, we pr... | identifying the 3fhl catalog. iv. swift observations of unassociated fermi-lat 3fhl sources |
we report on total ionizing dose effects on the x-ray soi pixel sensor, xrpix. xrpix has been developed as an imaging spectrometer for x-ray astronomical use in space. front- and back-illuminated (fi and bi) devices were irradiated with hard x-rays from an x-ray tube operated at 30 kv with a molybdenum target. we found... | total ionizing dose effects on the soi pixel sensor for x-ray astronomical use |
x-ray pulsars are complex magnetized astronomical objects in which many different attributes shape the pulse profiles of the emitted radiation. for each pulsar, the orientation of the spin axis relative to our viewing angle, the inclination of the magnetic dipole axis relative to the spin axis, and the geometries of th... | on the geometry of the x-ray emission from pulsars. i. model formulation and tests |
we have been developing monolithic active pixel sensors, named "xrpix", based on the silicon-on-insulator (soi) pixel technology for future x-ray astronomy satellites. xrpix has the function of event trigger and hit address outputs. this function allows us to read out analog signals only of hit pixels on trigger timing... | evaluation of kyoto's event-driven x-ray astronomical soi pixel sensor with a large imaging area |
the 2p-3s lines of fe xvii in the x-ray spectrum of the o-type star ζ puppis exhibit an anomalous (3g + m2)/(3f) line ratio of ~1.4, in comparison with ~2.4 for almost all other collisionally excited astrophysical spectra. based on the work of mauche et al., we conjectured that the strong uv field of ζ puppis produces ... | fe xvii 2p-3s line ratio diagnostic of shock formation radius in o stars |
we present the results of an intensive multiwavelength campaign on nova lmc 2012. this nova evolved very rapidly in all observed wavelengths. the time to fall two magnitudes in the v band was only 2 days. in x-rays the super soft phase began 13 ± 5 days after discovery and ended around day 50 after discovery. during th... | pan-chromatic observations of the remarkable nova large magellanic cloud 2012 |
we present a powerful new algorithm that combines both spatial information (event locations and the point-spread function) and spectral information (photon energies) to separate photons from overlapping sources. we use bayesian statistical methods to simultaneously infer the number of overlapping sources, to probabilis... | disentangling overlapping astronomical sources using spatial and spectral information |
the multiple star system of δ orionis is one of the closest examples of a system containing a luminous o-type, bright giant star (component aa1). it is often used as a spectral-type standard and has the highest observed x-ray flux of any hot-star binary. the main component aa1 is orbited by two lower mass stars, faint ... | hst/stis ultraviolet spectroscopy of the components of the massive triple star δ ori a |
w49b is the youngest supernova remnant (snr) to date that exhibits recombining plasma. the two prevailing theories of this overionization are rapid cooling via adiabatic expansion or through thermal conduction with an adjacent cooler medium. to constrain the origin of the recombining plasma in w49b, we perform a spatia... | spatially resolved study of recombining plasma in w49b using xmm-newton |
icecube has detected many tev-pev neutrinos, but their astrophysical origins remain largely unknown. motivated by the observed late-time x-ray/optical bumps in some gamma-ray bursts (grbs), we examine the correlation between icecube neutrinos and grbs allowing delayed neutrinos ∼days after the prompt gamma-rays. althou... | neutrino production associated with late bumps in gamma-ray bursts and potential contribution to diffuse flux at icecube |
we summarize the outcome of the 13th meeting of the international astronomical consortium for high energy calibration (iachec), held at tenuta dei ciclamini (avigliano umbro, italy) in april 2018. fifty-one scientists directly involved in the calibration of operational and future high-energy missions gathered during 3.... | summary of the 13th iachec meeting |
the cygnus superbubble (csb) is a region of soft x-ray emission approximately 13 degrees wide in the direction of the local spiral arm. such a large region might be the result of strong stellar winds and supernovae from nearby stellar nurseries, or it could be the result of a single event—a hypernova. halosat observed ... | a halosat analysis of the cygnus superbubble |
the analysis of individual x-ray sources that appear in a crowded field can easily be compromised by the misallocation of recorded events to their originating sources. even with a small number of sources, which none the less have overlapping point spread functions, the allocation of events to sources is a complex task ... | ebascs: disentangling overlapping astronomical sources ii, using spatial, spectral, and temporal information |
this work studies the dynamic response of solar wind charge exchange (swcx) soft x-ray emission in the earth's magnetosphere to the solar wind proton flux. unlike previous studies that attempted to use complex magnetohydrodynamic models to match the details of observed swcx of a necessarily limited number of cases, thi... | dynamical response of solar wind charge exchange soft x-ray emission in earth's magnetosphere to the solar wind proton flux |
progress within the field of x-ray astronomy depends on astronomical x-ray observations of ever-increasing quality and speed. fast and high-resolution x-ray observations over a broad spectral range promise amazing new discoveries. these observations, however, require a spaceborne x-ray telescope of unprecedented imagin... | fabrication of monocrystalline silicon x-ray mirrors |
diagnostics based on x-ray computed tomography (ct) are becoming increasingly important, not only in the medical field but in industry and cultural heritage. ct devices typical for medical applications, however, can seldom be used on art objects because both they are not easily transportable and they often present high... | computed tomography of a medium size roman bronze statue of cupid |
during its first 10 years of orbital operations swift dedicated approximately 11% of its observing time to blazars, carrying out more than 12,000 observations of ∼1600 different objects, for a total exposure time of over 25 million seconds. in this paper i briefly discuss the impact that swift is having on blazar multi... | multi-frequency, multi-messenger astrophysics with swift. the case of blazars |
recently, an original method for the statistical modeling of surface topography of state-of-the-art mirrors for usage in xray optical systems at light source facilities and for astronomical telescopes [opt. eng. 51(4), 046501, 2012; ibid. 53(8), 084102 (2014); and ibid. 55(7), 074106 (2016)] has been developed. in mode... | modeling surface topography of state-of-the-art x-ray mirrors as a result of stochastic polishing process: recent developments |
we present suzaku off-center observations of two poor galaxy groups, ngc 3402 and ngc 5129, with temperatures below 1 kev. through spectral decomposition, we measured their surface brightnesses and temperatures out to 530 and 1430 times the critical density of the universe for ngc 3402 and ngc 5129, respectively. these... | suzaku measurements of hot halo emission at outskirts for two poor galaxy groups: ngc 3402 and ngc 5129 |
the svom (space-based multi-band astronomical variable objects monitor) french-chinese mission is dedicated to the detection, localization and study of gamma ray bursts (grbs) and other high-energy transient phenomena. we first present the general description of the french payload composed of the eclairs instrument, de... | mxt instrument on-board the french-chinese svom mission |
a significant portion toward understanding evolution of the universe comes from x-ray astronomy since many astronomical objects of interest, such as black holes, supernovae and distant galaxies, emit radiation in the x-ray band. as basically all materials have almost unity refractive index for x-rays focusing x-ray bea... | ion-beam figuring of x-ray mirrors |
astronomical imaging with micro-arcsecond ($\mu$as) angular resolution could enable breakthrough scientific discoveries. previously-proposed $\mu$as x-ray imager designs have been interferometers with limited effective collecting area. here we describe x-ray telescopes achieving diffraction-limited performance over a w... | optical design of diffraction-limited x-ray telescopes |
the transition-edge sensor (tes) is an extremely sensitive device, which is used to measure the energy of individual x-ray photons. for astronomical spectrometry applications, sron develops a frequency domain multiplexing readout system for kilopixel arrays of such tess. each tes is voltage biased at a specific frequen... | frequency shift algorithm: design of a baseband phase locked loop for frequency-domain multiplexing readout of x-ray transition-edge sensor microcalorimeters |
planetary nebulae (pne) are expected to have a ∼105 k interface layer between the ≥slant 106 k inner hot bubble and the ∼104 k optical nebular shell. the pn structure and evolution, and the x-ray emission, depend critically on the efficiency of the mixing of material at this interface layer. however, neither its locati... | hst stis observations of the mixing layer in the cat’s eye nebula |
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