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radiometry, i.e. measuring the power of electromagnetic radiation—hitherto often referred to as "photometry"—is of fundamental importance in astronomy. we provide an overview of how to achieve a valid laboratory calibration of space telescopes and discuss ways to reliably extend this calibration to the spectroscopic te... | spectroradiometry with space telescopes |
the japanese x-ray astronomy satellite, hitomi (astro-h) carries hard x-ray imaging system, covering the energy band from 5 kev to 80 kev. the hard x-ray imaging system consists of two hard x-ray telescopes (hxt) and the focal plane detectors (hxi). the hxt employs tightly-nested, conically-approximated thin foil wolte... | performance of astro-h hard x-ray telescope (hxt) |
one of the developments at msfc that is underway to meet the demand of high-resolution x-ray optics for future x-ray astronomy missions is the `differential deposition' technique. this process corrects the axial figure profile of optics by selectively depositing material onto the mirror's reflective surface. the proces... | progress in differential deposition for improving the figures of full-shell astronomical grazing incidence x-ray optics |
we present the spex software package for modeling and fitting x-ray spectra. our group has developed spectral models, atomic data and code for x-ray applications since the 1970's. since the 1990's these are further developed in the public spex package. in the last decades, x-ray spectroscopy has been revolutionized by ... | spex: high-resolution spectral modeling and fitting for x-ray astronomy |
astronomical x-ray observatories with grazing incidence optics face the problem of pseudo-focusing of low energy protons from the mirrors towards the focal plane. those protons constitute a variable, unpredictable component of the non x-ray background that strongly affects astronomical observations and a correct estima... | soft proton scattering at grazing incidence from x-ray mirrors: analysis of experimental data in the framework of the non-elastic approximation |
one of the youngest known remnants of a core-collapse supernova (sn) in our galaxy is g320.4-1.2/msh 15-52, containing an energetic pulsar with a very short (1700 yr) spindown age and likely produced by a stripped-envelope sn ibc. bright x-ray and radio emission north of the pulsar overlaps with an hα nebula rcw 89. th... | fast blast wave and ejecta in the young core-collapse supernova remnant msh 15-52/rcw 89 |
son of x-shooter (soxs) will be a new instrument designed to be mounted at the nasmyth--a focus of the eso 3.5 m new technology telescope in la silla site (chile). soxs is composed of two high-efficiency spectrographs with a resolution slit product 4500, working in the visible (350 -- 850 nm) and nir (800 -- 2000 nm) r... | son of x-shooter: a multi-band instrument for a multi-band universe |
in the last decade, using single epoch virial based techniques in the optical band, it has been possible to measure the central black hole mass on large type 1 active galactive nuclei (agn) samples. however these measurements use the width of the broad line region as a proxy of the virial velocities and are therefore d... | detection of faint blr components in the starburst/seyfert galaxy ngc 6221 and measure of the central bh mass |
astronomical observations of distant quasars may be important to test models for quantum gravity, which posit planck-scale spatial uncertainties ('spacetime foam') that would produce phase fluctuations in the wavefront of radiation emitted by a source, which may accumulate over large path lengths. we show explicitly ho... | new constraints on quantum foam models from x-ray and gamma-ray observations of distant quasars |
astronomical observations in the x-ray band are subject to atmospheric attenuation and have to be performed in the space. cubesats offer a cost effective means for space-based x-ray astrophysics but allow only limited mass and volume. in this article, we describe two successful cubesat-based missions, halosat and polar... | the halosat and polarlight cubesat missions for x-ray astrophysics |
over the past two decades, i have been actively involved in teaching astronomy and astrophysics to chicago public school (cps) students and their teachers, in collaboration with various groups as well as by myself. valuable resources that we have created for schools include the multiwavelength astronomy website, with m... | two decades of education and public outreach with chicago public schools |
despite the impressive progresses achieved both by x-ray and gamma-ray observatories in the last decades, the energy range between $\sim 200\,\mathrm{kev}$ and $\sim 50\,\mathrm{mev}$ remains poorly explored. comptel, on-board cgro (1991-2000), was the last telescope to accomplish a complete survey of the mev-sky with ... | mevcube: a cubesat for mev astronomy |
in the context of time domain astronomy, we present an offline detection search of gamma-ray transients using a wild binary segmentation analysis called f-wbsb targeting both short and long gamma-ray bursts (grbs) and covering the soft and hard gamma-ray bands. we use nasa fermi/gbm archival data as a training and test... | detection of gamma-ray transients with wild binary segmentation |
we summarize the 14th meeting of the international astronomical consortium for high energy calibration (iachec) held at \textit{shonan village} (kanagawa, japan) in may 2019. sixty scientists directly involved in the calibration of operational and future high-energy missions gathered during 3.5 days to discuss the stat... | summary of the 14th iachec meeting |
aims: we aim to analyse our study of the x-ray transient swift j1745-26, using observations obtained from its outburst in september 2012, up to its decay towards quiescence in march 2013.methods: we obtained optical and infrared observations, through override programme at eso/vlt with fors2 and isaac instruments, and a... | broad-band spectral energy distribution of the x-ray transient swift j1745-26 from outburst to quiescence |
arguably, no mission changed x-ray astronomy in as short a time as did hitomi. the planned x-ray astronomy recovery mission, xarm, will carry its legacy forward. | fourth time's a xarm |
x-ray hybrid cmos detectors (hcds) have advantages over x-ray ccds due to their higher readout rate abilities, flexible readout, inherent radiation hardness, and low power, which make them more suitable for the next generation large-area x-ray telescope missions. the penn state high energy astronomy laboratory has been... | x-ray hybrid cmos detectors: recent development and characterization progress |
over the past half-century, x-ray and radio observations of accreting neutron stars and stellar-mass black holes have yielded a rich observational picture, with common features including state transitions and jet formation, but also sharp differences. while black hole x-ray binaries overwhelmingly suppress jets in so-c... | the generalized hardness-intensity diagram for black hole and neutron star x-ray binaries |
pulsar studies in the recent years have shown, more than others, to have benefited from a multi-wavelength approach. the inaf-astronomical observatory in cagliari (inaf-oac) is a growing facility with a young group devoted to pulsar and fast-transient studies across the electromagnetic spectrum. taking advantage of thi... | a multi-wavelength pipeline for pulsar searches |
phase retrieval (pr), also sometimes referred to as quadratic sensing, is a problem that occurs in numerous signal and image acquisition domains ranging from optics, x-ray crystallography, fourier ptychography, sub-diffraction imaging, and astronomy. in each of these domains, the physics of the acquisition system dicta... | non-convex structured phase retrieval |
the intracluster medium of a galaxy cluster often shows an extended quasi-spiral structure, accentuated by tangential discontinuities known as cold fronts (cfs). these discontinuities are thought to isolate between low-entropy, high-metallicity gas inside (i.e., below) the cf that was lifted from the center of the clus... | advection by large-scale spiral flows in galaxy clusters |
we present two years of neutron star interior composition explorer (nicer) x-ray observations of three energetic rotation-powered millisecond pulsars (msps): psrs b1937+21, b1821-24, and j0218+4232. we fit gaussians and lorentzians to the pulse profiles for different energy sub-bands of the soft x-ray regime to measure... | a nicer view of spectral and profile evolution for three x-ray-emitting millisecond pulsars |
after many years of flying in space primarily for educational purposes, cubesats - tiny satellites with form factors corresponding to arrangements of "1u" units, or cubes, each 10 cm on a side - have come into their own as valuable platforms for technology advancement and scientific investigations. cubesats offer compa... | cubesats for gamma-ray astronomy |
it is well established that brightest cluster galaxies (bcgs), residing in the centers of galaxy clusters, are typically massive and quenched galaxies with cd or elliptical morphology. an optical survey suggested that an exotic galaxy population, superluminous spiral and lenticular galaxies, could be the bcgs of some g... | detection of a superluminous spiral galaxy in the heart of a massive galaxy cluster |
we have developed a simulation-based method of spectral analysis for pile-up-affected data of x-ray ccds without any loss of photon statistics. as effects of the photon pile-up appear as complicated nonlinear detector responses, we employ a detailed simulation to calculate the important processes in an x-ray observatio... | simulation-based spectral analysis of x-ray ccd data affected by photon pile-up |
the next generation of electromagnetic and gravitational wave observatories will open unprecedented windows to the birth of the first supermassive black holes. this has the potential to reveal their origin and growth in the first billion years, as well as the signatures of their formation history in the local universe.... | revealing the origin and cosmic evolution of supermassive black holes |
in december 2020, at the 2-m telescope of the terskol branch of the institute of astronomy, we carried out spectrophotometric observations in the range of ~0.36-0.95 μm of nine asteroids of the main belt (19 fortuna, 52 europa, 102 miriam, 177 irma, 203 pompeja, 250 bettina, 266 aline, 379 huenna, and 383 janina), whic... | spectral signs of simultaneous sublimation activity and the appearance of a dust exosphere on eight asteroids of the main belt near perihelion |
ultraviolet and x-rays from radiation sources disperse nearby gas clumps by driving winds due to heating associated with the photochemical processes. this dispersal process, photoevaporation, constrains the lifetimes of the parental bodies of stars and planets. to understand this process in a universal picture, we deve... | anatomy of photoevaporation base: linking the property of the launched wind to irradiation flux |
fast radio bursts (frbs) are cosmological radio transients with an unclear generation mechanism. known characteristics such as their luminosity, duration, spectrum, and repetition rate, etc., suggest that frbs are powerful coherent radio signals at ghz frequencies, but the status of frbs near the source remains unknown... | upper field-strength limit of fast radio bursts |
we have been developing the monolithic active pixel detector xrpix onboard the future x-ray astronomical satellite force. xrpix is composed of complementary metal-oxide-semiconductor pixel circuits, sio2 insulator, and si sensor by utilizing the silicon-on-insulator (soi) technology. when the semiconductor detector is ... | x-ray radiation damage effects on double-soi pixel detectors for the future astronomical satellite force |
transition edge sensors detector devices, like the core of the x-ifu instrument that will be on-board the athena x-ray observatory, produce current pulses as a response to the incident x-ray photons. the reconstruction of these pulses has been traditionally performed by means of a triggering algorithm based on the deri... | event detection and reconstruction using neural networks in tes devices: a case study for athena/x-ifu |
we present a joint spectral analysis of rosat pspc, swift x-ray telescope, and nuclear spectroscopic telescope array focal plane module a/b (fpma/b) data of the nova-like (nl) cataclysmic variables (cvs) bz cam and v592 cas in the 0.1-78.0 kev band. plasma models of collisional equilibrium fail to model the 6.0-7.0 iro... | characterizing the advective hot flows of nova-like cataclysmic variables in the x-rays: the case of bz cam and v592 cas |
astrosat is india's first ultra-violet (uv) and x-ray astronomy observatory in space. the satellite was launched by the indian space research organisation on a polar satellite launch vehicle on 28 september 2015 from sriharikota range north of chennai on the eastern coast of india. astrosat carries five scientific inst... | the astrosat observatory |
the most recent studies suggest that almost all galaxies in the local universe host super-massive black holes (smbhs) in their center. smbhs are responsible for the most powerful phenomena in the universe, the active galactic nuclei (agn). when smbhs accrete matter, strong radiation is emitted at all wavelengths of the... | identification of active galactic nuclei through different selection techniques |
our present knowledge of the properties of blazars mostly comes from small samples of bright objects, especially regarding studies on their cosmological evolution. statistically well-defined and completely identified samples of faint blazars are very difficult to obtain. we present a new x-ray selected sample of 62 bla... | a new sample of x-ray selected swift/sdss faint blazars and blazar candidates |
the off-plane grating rocket experiment (ogre) is a sub-orbital rocket payload that will make the highest spectral resolution astronomical observation of the soft x-ray universe to date. capella, ogre's science target, has a well-defined line emission spectrum and is frequently used as a calibration source for x-ray ob... | the off-plane grating rocket experiment (ogre) system overview |
contained within a galaxy cluster, the intracluster medium is comprised of hot, x-ray emitting material between member galaxies. the nearest (~16.1 mpc) large galaxy cluster is virgo. virgo covers an approximately 12° diameter field, making it challenging to observe in its entirety. the halosat satellite utilized a 7° ... | halosat observation of the virgo intracluster medium |
incom inc. is developing and commercializing microchannel plate (mcp) electron multiplier devices made from leadfree glass capillary array (gca) substrates that are functionalized using atomic layer deposition (ald) thin film coating technology. notable benefits over conventional lead-oxide based mcp technology are lar... | large-area, high-resolution atomic layer deposited microchannel plates for uv imaging and particle identification in space science applications |
the gamma-ray monitor (grm), which is one of the four main scientific instruments onboard the space-based multi-band astronomical variable objects monitor (svom) satellite, is dedicated to the spectrum measurement and study of gamma-ray bursts (grbs) in the 15 kev to 5 mev energy band, as well as to perform real-time t... | calibration study of the gamma-ray monitor onboard the svom satellite |
recent advances in the fabrication of silicon mirrors and their alignment and integration methods make it possible to build large-area, lightweight, high-resolution x-ray telescopes with arc-second angular resolution. such a telescope, having simultaneously arc-second resolution and large (> 1 m2 ) collecting area, ... | alignment and bonding of silicon mirrors for high-resolution astronomical x-ray optics |
the beatrix (beam expander testing x-ray) facility, being completed at inaf-brera astronomical observatory, will represent an important step in the acceptance roadmap of silicon pore optics mirror modules, and so ensure the final angular resolution of the athena x-ray telescope. aiming at establishing the final angular... | performance simulations for the ground-based, expanded-beam x-ray source beatrix |
magnetic fields have an enormous influence on the behavior of plasma, especially around stars and planets. when winds flowing from stars encounter strong magnetic structures, both field and flow change their very natures. in this thesis, i ask the question: how do stellar winds interact with planetary and stellar magne... | tools for studying magnetospheric-wind interactions |
since 2009, cea have started a long term program to achieve the collective realisation of a large (32x32 pixels) μ-calorimeters camera for x-ray astrophysics. this camera is based on silicon doped sensors with composite tantalum absorber readout thanks to hemt/sige based cryo-electronics. the goal of this development i... | large x-rays high impedance μ-calorimeters matrices: status and prospects |
teledyne e2v has developed the capella cis120 which is a general purpose cmos image sensor with high quantum efficiency that has been specifically designed for space applications and is planned to be used for different copernicus programs. we will describe the considerations that led to this cmos sensor concept and the... | capella: cis120 general purpose cmos sensor for space applications |
we report on a concept for curved diffractive x-ray optics (cdxo). cdxo would enable potential new optical designs for x-ray instruments, such as a two element spectrometer, in which the secondary element of an x- ray mirror pair is patterned with an x-ray grating. a two-element spectrometer design eliminates the grati... | curved diffractive x-ray optics for astronomy |
adjustable x-ray optics is the technology under study by sao and psu for the realization of the proposed x-ray telescope lynx. the technology is based on thin films of lead-zirconate-titanate (pzt) deposited on the back of thermally formed thin substrates, and represents a potential solution to the challenging trade-of... | progress in development of adjustable optics for x-ray astronomy |
future astronomical x-ray spectrometer missions call for high spectral resolution in conjunction with high throughput. to achieve both of these requirements simultaneously, many grating elements must be aligned such that their diffraction arcs overlap at the focal plane. methods for the alignment of reflection gratings... | a comprehensive line spread function error budget for the off-plane grating rocket experiment |
the beatrix (beam expander testing x-ray) facility under construction at inaf-brera astronomical observatory aims at performing the acceptance tests of the silicon pore optics mirror modules of the athena (advanced telescope for high-energy astrophysics) x-ray observatory. the facility implements a grazing-incidence co... | manufacturing and testing of the x-ray collimating mirror for the beatrix facility |
here we report our first spectral observations of be/x-ray and γ-ray binaries obtained with the new echelle spectrograph of the national astronomical observatory rozhen. for four objects (lsi+61°303, γ cas, mwc 148, 4u 2206+54), we report the parameters and estimate the sizes of their circumstellar discs using differen... | circumstellar discs in x/γ-ray binaries: first results from the echelle spectrograph |
here we present research on an ultra-luminous x-ray source (ulx) candidate 2xmm j140229.91+542118.8. the x-ray light curves of this ulx candidate in m101 exhibit features of a flare star. more importantly, the chandra light curve displays unusual x-ray double flares, which is comprised of two close peaks. the x-ray (0.... | an active m star with x-ray double flares disguised as an ultra-luminous x-ray source |
over the past 2 decades, researchers have found hundreds of radioactive atoms, trapped in seafloor minerals, that came from an ancient supernova explosion marking the death of a nearby star. erupting from hundreds of light-years away, the flash of x-rays and gamma rays probably did no harm on earth. but the expanding f... | starstruck |
a crystal of ammonium dihydrogen phosphate is characterized with respect to its crystallographic quality and the presence of residual strain. the crystal quality is fundamental in view of its use in the beatrix x-ray facility for testing silicon pore optics modules of the athena x-ray telescope. | characterization of ammonium dihydrogen phosphate crystals for soft x-ray optics of the beam expander testing x-ray facility (beatrix) |
we present surveys and related studies of active galaxies carried out at the nas ra v.ambartsumian byurakan astrophysical observatory (bao). this has been one of the main research subjects at bao for many years since the mid-1950s, when viktor ambartsumian suggested the hypothesis of the activity of the galactic nuclei... | multiwavelength search for and studies of active galaxies |
in this work we present the results of imaging simulations performed with the help of the geant4 package for the protomirax hard x-ray balloon experiment. the instrumental background was simulated taking into account the various radiation components and their angular dependence, as well as a detailed mass model of the ... | telescope performance and image simulations of the balloon-borne coded-mask protomirax experiment |
since 2018 july, the black hole x-ray binary grs 1915+105 has been in an x-ray low luminous state (xlls), which is the faintest period ever observed in a soft x-ray band. we present here the results of near-infrared (nir) observations from 2019 april-december in the xlls using honir attached to the kanata telescope, to... | origins of the long-term variability of the near-infrared emission of the black hole x-ray binary grs 1915+105 in the x-ray low luminous state |
the intrinsic random variability of an astronomical source hampers the detection of possible periodicities that we are interested in. we find that a simple first-order autoregressive [ar(1)] process gives a poor fit to the power decay in the observed spectrum for astrophysical sources and geodetic observations. thus, a... | detecting periodic oscillations in astronomy data: revisiting wavelet analysis with coloured and white noise |
we have employed electron stimulated desorption (esd) and x-ray photoelectron spectroscopy (xps) to study the chemical species generated from multilayer films of n2o, c2d2, and mixtures thereof (i.e., n2o/c2d2) by the impact of low energy electrons with energies between 30 and 70 ev. our esd results for pure films of n... | chemical transformation of molecular ices containing n2o and c2d2 by low energy electrons: new chemical species of astronomical interest |
soft x-ray telescope (sxt) built on the principle of grazing incidence optics was launched on-board astrosat on september 28, 2015, and made operational on october 26, 2015. the telescope optics consists of two conical sections of approximate paraboloid and hyperboloid mirror segments arranged in wolter type-i design. ... | pre-flight evaluation of the soft x-ray telescope optics aboard astrosat |
we discuss mathematical methods for analysis of the x-ray observational data to obtain a distribution of the main physical parameters of x-ray galaxy clusters. first of all, this is the binning of galaxy cluster imagery on the concentration rings around the central parts. it allows us to calculate the integrated amount... | new approach for analysis of the x-ray data in cores of galaxy clusters: binning on the concentration rings, contour binning, and wavelet transforms |
this memoir is a summary of my early childhood, education, and research career at the naval research laboratory (nrl) in washington, dc. i describe my early interest in astronomy and how i wound up working in the fields of solar physics and x-ray-uv spectroscopy of high temperature plasmas. i describe some of my home l... | adventures in space science |
the detector modelling (demo) workshops aim to bring together a community of scientists and engineers who are interested in modelling detector effects and simulating detectors for astronomy. the first such workshop was held online over three afternoons from 14 to 16 june 2021. the three afternoons were organised around... | report on the eso/esa workshop "detector modelling workshop 2021" |
thermonuclear supernovae (sne ia) are one of the building blocks of modern cosmology and laboratories for the explosion physics of white dwarf star/s (wd) in close binary systems. the second star may be a wd (double degenerate systems, dd), or a non-degenerated star (sd) with a main sequence star, red giant or a helium... | signatures of progenitors of type ia supernovae |
the virtual telescope for x-ray observations (vtxo) is a conceptual mission under development to demonstrate a new instrument for astronomical observations in the x-ray band using a set of 6u cubesats. vtxo will use a phase fresnel lens, which has the potential to improve the imaging resolution several orders of magnit... | vtxo - virtual telescope for x-ray observations |
the medium energy gamma-ray astronomy library (megalib) simulates, calibrates, and analyzes data of hard x-ray and gamma-ray detectors, with a specialization on compton telescopes. the library comprises all necessary data analysis steps for these telescopes, from simulation/measurements via calibration, event reconstru... | megalib: medium energy gamma-ray astronomy library |
data on the cassiopeia a supernova remnant from nasa and other sources have been rendered into a three-dimensional virtual reality (vr) and augmented reality (ar) programme, which is the first of its kind. this data-driven experience of a supernova remnant allows viewers to take a virtual walk inside the leftovers of a... | walking through an exploded star: rendering supernova remnant cassiopeia a into virtual reality |
context. laboratory analogues can provide physical constraints to the interpretation of astronomical observations of cosmic dust but clearly do not experience the same formation conditions. to distinguish between properties intrinsic to the material and properties imprinted by their means of formation requires extensiv... | amorphous mg-fe silicates from microwave-dried sol-gels. multi-scale structure, mid-ir spectroscopy and thermal crystallisation |
particle-induced background, or "instrument background", produced from the interaction of background photons and charged particles with a detector, either as primaries or through the generation of secondary photons or particles, is one of the major sources of background for the focal plane sensors in x-ray astronomy mi... | predicting the particle-induced background for future x-ray astronomy missions: the importance of experimental validation for geant4 simulations |
1. introduction; 2. gathering light - the telescope; 3. sensing the light: detectors for the optical and infrared; 4. imaging and astrometry; 5. photometry and polarimetry; 6. spectroscopy; 7. adaptive optics (ao) and high contrast imaging; 8. submillimeter and radio astronomy; 9. interferometry and aperture synthesis;... | measuring the universe |
x-ray astronomy uses space-based telescopes to overcome the disturbing absorption of the earth's atmosphere. the telescope mirrors are operating at grazing incidence angles and are coated with thin metal films of high-z materials to get sufficient reflectivity for the high-energy radiation to be observed. in addition t... | prototyping iridium coated mirrors for x-ray astronomy |
the x-ray astronomy satellite astro-h, which is the 6th japanese x-ray astronomy satellite and is renamed hitomi after launch, is designed to observe celestial x-ray objects in a wide energy band from a few hundred ev to 600 kev. the soft x-ray telescopes (sxts) onboard astro-h play a role of collecting and imaging x-r... | the astro-h sxt performance to the large off-set angles |
high-resolution, high throughput optics for x-ray astronomy entails fabrication of well-formed mirror segments and their integration with arc-second precision. in this paper, we address issues of aligning and bonding thin glass mirrors with negligible additional distortion. stability of the bonded mirrors and the curin... | aligning, bonding, and testing mirrors for lightweight x-ray telescopes |
we have been developing a monolithic active pixel sensor, "xrpix", for the japan led future x-ray astronomy mission "force" observing the x-ray sky in the energy band of 1-80 kev with angular resolution of better than 15''. xrpix is an upper part of a stack of two sensors of an imager system onboard force, and covers t... | subpixel response of soi pixel sensor for x-ray astronomy with pinned depleted diode: first result from mesh experiment |
we propose an image reconstruction method for an x-ray telescope system with an angular resolution booster proposed by maeda et al. (2018, pasj, submitted). the system consists of double multi-grid masks in front of an x-ray mirror and an off-focused two-dimensional imager. because the obtained image is off-focused, an... | an image reconstruction method for an x-ray telescope system with an angular resolution booster |
the short-term x-ray variability of tidal disruption events (tdes) and its similarities with that of active galactic nuclei are poorly understood. in this work, we show the diversity of tdes' short-term x-ray variability, and take swift j1644+57 as an example to study the evolution of various properties related to the ... | long-term evolution of the short-term x-ray variability of the jetted tde swift j1644+57 |
çukurova university space sciences and solar energy research and application center (uzaymer) was founded in 1991. in this work, we present current research in the fields of astronomy, astrophysics and solar energy and the astronomical infrastructure of the center. in addition, the astrometrological status of uzaymer w... | ç.ü. uzay bilimleri ve güneş enerjisi araştırma ve uygulama merkezi (uzaymer) : i. gözlem koşulları ve güncel projeler |
with the application of advanced astronomical technologies, equipments and methods all over the world, astronomical observations cover the range from radio, infrared, visible light, ultraviolet, x-ray and gamma-ray bands, and enter into the era of full wavelength astronomy. how to effectively integrate data from differ... | astronomical data fusion tool based on postgresql |
we present the status of the laue project devoted to develop a technology for building a 20 meter long focal length laue lens for hard x-/soft gamma-ray astronomy (80-600 kev). the laue lens is composed of bent crystals of gallium arsenide (gaas, 220) and germanium (ge, 111), and, for the first time, the focusing prope... | hard x-ray broad band laue lenses (80-600 kev): building methods and performances |
making mock simulated catalogs is an important component of astrophysical data analysis. selection criteria for observed astronomical objects are often too complicated to be derived from first principles. however the existence of an observed group of objects is a well-suited problem for machine learning classification.... | machine learning etudes in astrophysics: selection functions for mock cluster catalogs |
astronomy has been an inherently visual area of science for millenia, yet a majority of its significant discoveries take place in wavelengths beyond human vision. there are many people, including those with low or no vision, who cannot participate fully in such discoveries if visual media is the primary communication m... | touching the stars: improving nasa 3d printed data sets with blind and visually impaired audiences |
we have been developing monolithic active pixel sensors for x-rays based on the silicon-on-insulator technology. our device consists of a low-resistivity si layer for readout cmos electronics, a high-resistivity si sensor layer, and a sio$_2$ layer between them. this configuration allows us both high-speed readout circ... | performance of soi pixel sensors developed for x-ray astronomy |
x-ray astronomy recovery mission (xarm) scheduled to be launched in early 2020's carries two soft x-ray telescopes. one is resolve consisting of a soft x-ray mirror and a micro calorimeter array, and the other is soft x-ray imaging telescope (xtend), a combination of an x-ray mirror assembly (xma) and an x-ray ccd came... | soft x-ray imaging telescope (xtend) onboard x-ray astronomy recovery mission (xarm) |
we performed a detailed modelling of the background counts observed in a phoswich scintillator x-ray detector at balloon altitude, used for astronomical observations, on board small scientific balloon. we used monte carlo simulation technique in geant4 simulation environment, to estimate the detector background from va... | background model of phoswich x-ray detector on board small balloon |
the long-standing galactic center gamma-ray excess could be explained by gev dark matter (dm) annihilation, but the dm interpretation seems to conflict with recent joint limits from different astronomical scale observations such as dwarf spheroidal galaxies, the milky way halo, and galaxy groups/clusters. motivated by ... | interpretation of the galactic gamma-ray excess with the dark matter indicated by 8be and 4he anomalous transitions |
soft protons are a potential threat for x-ray missions using grazing incidence optics, as once focused onto the detectors they can contribute to increase the background and possibly induce radiation damage as well. the assessment of these undesired effects is especially relevant for the future esa x-ray mission athena,... | scattering efficiencies measurements of soft protons at grazing incidence from an athena silicon pore optics sample |
metals form an essential part of the universe at all scales. without metals we would not exist, and the cosmos would look completely different. metals are primarily born through nuclear processes in stars. they leave their cradles through winds or explosions, and then start their journey through space. this can lead th... | the voyage of metals in the universe from cosmological to planetary scales: the need for a very high-resolution, high throughput soft x-ray spectrometer |
x-ray spectral fitting of astronomical sources requires convolving the intrinsic spectrum or model with the instrumental response. standard forward modeling techniques have proven success in recovering the underlying physical parameters in moderate to high signal-to-noise regimes; however, they struggle to achieve the ... | a data-driven approach to x-ray spectral fitting: quasi-deconvolution |
the icecube neutrino observatory has detected high-energy astrophysical neutrinos in the tev-pev range. these neutrinos have an isotropic distribution on the sky, and therefore, likely originate from extragalactic sources. active galactic nuclei form a class of astronomical objects which are promising neutrino source c... | search for high-energy neutrino emission from hard x-ray agn with icecube |
aims: in this paper we present new optical observations of the galaxy ngc 185 intended to reveal the status of supernova remnants (snrs) in this dwarf companion of the andromeda galaxy. previously, it was reported that this galaxy hosts one snr.methods: our deep photometric study with the 2m telescope at rozhen nationa... | revealing the nature of central emission nebulae in the dwarf galaxy ngc 185 |
prof. gregory sivakoff (university of alberta) provides the following material: "patrick schmeer has identified that vy aqr, an accreting white dwarf (aka cataclysmic variable) has gone into an outburst that looks to be a superoutburst (https://www.aavso.org/vy-aqr-outburst). vy aqr is brighter than 10th magnitude righ... | vy aqr observing campaign |
continuing advances in observational astronomy may detect exoplanets around exotic systems such as a binary of a compact object - white dwarf, neutron star or black hole - with a stellar companion. their formation history includes tidal capture, familiar from studies of x-ray binaries, that may put exoplanets on co- or... | stability of p-type orbits around stellar binaries: an extension to counter-rotating orbits |
the space-based multi-band astronomical variable objects monitor (svom) is a chinese-french satellite dedicated to the observation and study of gamma-ray bursts (grbs) and other variable sources. among the four scientific payloads onboard svom, the gamma-ray monitor (grm) is designed to detect grbs in the 15 kev to 5 m... | in-orbit background simulation study of svom/grm |
in x ray region, the supermirror can provide better optical performance than metal substrate or two-layer mirror. w/si supermirrors are designed in 0.2-10 kev by block method. these mirrors have big grazing incidence angles of 1.0, 1.4, and 1.7 degrees, which is the most important characteristic in our job. compared wi... | design of w/si supermirror by block method |
a new time-domain astronomy experiment performed with the swift satellite is ongoing since mid oct. 2016 on the peculiar bl lac object oj 287 (z=0.306) after the observation of a very-high optical flux (private communication and follow-up atel#9650 and atel#9675). | swift observation of strong optical-uv and x-ray flaring activity of oj 287 |
soxs (son of x-shooter) is a single object spectrograph, characterized by offering a wide simultaneous spectral coverage from u- to h-band, built by an international consortium for the 3.6-m eso new technology telescope at the la silla observatory, in the southern part of the chilean atacama desert. the consortium is f... | development status of the soxs spectrograph for the eso-ntt telescope |
mechanical active galactic nucleus (agn) feedback plays a key role in massive galaxies, galaxy groups, and clusters. however, the energy content of agn jets that mediate this feedback process is still far from clear. here we present a preliminary study of radial elongations τ of a large sample of x-ray cavities, which ... | probing the physics of mechanical agn feedback with radial elongations of x-ray cavities |
the hot universe baryon surveyor (hubs) is a satellite mission that is proposed to probe "hidden" baryons in the universe and thus to fill a void in observational astronomy that seriously affects our understand of galaxy formation and evolution. the hubs payload is highly optimized for detecting diffuse x-ray emission ... | making mock hubs observations with illustristng |
all galaxies evolve embedded in a vast gaseous halo --- the circumgalactic medium (cgm) --- that dwarfs the mass and spatial extent of the stars in the galactic disk. recent ultraviolet (uv) absorption studies reveal that the cgm has a rich, multiphase structure shaped by metal-rich galactic winds that expel the byprod... | simulating multiphase galactic halos: the impact of cosmic rays through an observational lens |
for space-born astronomical x-ray telescopes, iridium-based reflective layer systems are known as highly effective mirrors coatings. during the recent years, aschaffenburg university of applied sciences and the czech technical university in prague jointly developed stress compensated chromium-iridium coatings for this ... | lobster eye type x-ray telescope with chromium-iridium coated tri-layer mirrors |
understanding and reducing in-orbit instrumental backgrounds are essential to achieving high sensitivity in hard x-ray astronomical observations. the observational data of the hard x-ray imager (hxi) onboard the hitomi satellite provide useful information on the background components due to its multilayer configuration... | origin of the in-orbit instrumental background of the hard x-ray imager onboard hitomi |
we report the first x-ray detection of sn2020tcw with the chandra x-ray observatory (cxo) at 60 days post-discovery (program #21500443, pi margutti). sn2020tcw was discovered on september 12th 2020 (tonry et al., tns astronomical transient report no. 81951) and classified as a hydrogen-poor super-luminous supernova (pe... | x-ray detection of the slsn-i 2020tcw |
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