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the wootton center for astrophysical plasma properties (wcapp) is a new center focusing on the spectroscopic properties of stars and accretion disks using "at-parameter" experiments. currently, these experiments use the x-ray output of the z machine at sandia national laboratories — the largest x-ray source in the worl... | the wootton center for astrophysical plasma properties: first results for helium |
x-ray reflection near the brewster's angle by multilayer mirrors can be used to detect the polarization from x-ray sources. the photon emission spectra from some isolated neutron stars and agn/blazars etc. show that their emission is peaked at low energies near 250ev, which is just below carbon k-absorption edge. the l... | high efficiency carbon-based multilayers for lamp at 250 ev |
around 1900, a group of sponge divers, pulled out from an ancient roman shipwreck, near the antikythera island, a piece of a hardly distinguishable geared mechanism which is known since then as "the antikythera mechanism". until now the exact use of some of its survived gears is investigated and there are speculations ... | the influence of hipparchus in antikythera mechanism |
the astronomical resource cross-matching for high energy studies (arches) project is a fp7-space funded programme started in 2013 and involving the observatoire astronomique de strasbourg including the cds (france), the leibniz- institut für astrophysik potsdam (germany), the university of leicester (uk), the universid... | the arches project |
we have developed a process for indirectly coating arbitrarily small diameter electroformed nickel replicated optics with multilayers to increase their response at high energy (i.e. >10 kev). the ability to fabricate small diameter multilayer coated full shell wolter x-ray optics with narrow bandpass opens the door ... | characterization of multilayer coated replicated wolter optics for imaging x-ray emission from pulsed power |
canada has thriving communities in cmb (cosmic microwave background) studies, cosmology and submillimetre (submm) astronomy, with involvement in many facilities that featured prominently in previous astronomy long range plans. the standard cosmological model continues to be well fit using a small number of parameters. ... | cosmology in front of the background: studying the growth of structure at cmb wavelengths |
akari performed about 10,000 spectroscopic observations with the infrared camera (irc). these irc observations provide unique spectral data at near- and mid-infrared wavelengths. these data enable astronomical research in the various fields throughout the next few decades, empowered by its high sensitivity and unique w... | akari/irc near-infrared point source spectral catalogue |
the multiwavelength detection of gw170817 has inaugurated multimessenger astronomy. the next step consists in interpreting observations coming from population of gravitational wave sources. we introduce sapremo, a tool aimed at predicting the number of electromagnetic signals characterized by a specific light curve and... | sapremo: a simplified algorithm for predicting detections of electromagnetic transients in surveys |
v404 cyg, an x-ray nova and a low mass x-ray binary (lmxb) with black hole component, is undergoing its first reported x-ray and optical outburst since 1989. large scale, rapid variations are being reported in wavelengths from x-ray to radio by professional and amateur astronomers worldwide. satellite and ground-based ... | x-ray nova and lmxb v404 cyg in rare outburst |
the slumping glass optics technology for the fabrication of astronomical x-ray mirrors has been developed in recent years in usa and europe. the process has been used for making the mirrors of the nustar, mission. the process starts with very thin glass foils hot formed to copy the profile of replication moulds. at ina... | x-ray mirror prototype based on cold shaping of thin glass foils |
the large magellanic cloud (lmc) is among the best laboratories for studying various astronomical objects and their physics because of its almost face-on inclination to us, and a well-known distance ( 50 kpc). supernova remnants (snrs) in the lmc were well studied by radio continuum, optical, and x-ray observations (e.... | alma co observations toward the magellanic supernova remnants |
the only space weather monitor located in colombia, that at the present time continuously reports on x-ray solar activity, is the monitor that belongs to the research group astroingeniería alfa orión. this device is officially registered as utp 0383 in the stanford solar center server and is located at the observatorio... | space weather monitoring from observatorio astronómico of the universidad tecnológica de pereira |
we discuss a technique for detecting and locating rapid transient electromagnetic counterparts to gravitational wave sources that affords a reprieve of several hours after the gravitational wave event. the technique relies on detecting a scattering halo produced if x-rays emitted at the gravitational wave event scatter... | detecting and locating electromagnetic counterparts to gravitational wave sources using galactic dust scattering halos |
on 25 march 2016, the japanese 6th x-ray astronomical satellite astro-h (hitomi), launched on february 17, lost communication after a series of mishap in its attitude control system. in response to the mishap the x-ray astronomy community and jaxa analyzed the direct and root cause of the mishap and investigated possib... | the x-ray astronomy recovery mission |
similarity metrics, kernels and similarity-based algorithms have gained much attention due to their increasing applications in information retrieval, data mining, pattern recognition and machine learning. similarity graphs are often adopted as the underlying representation of similarity matrices and are at the origin o... | clustering by reordering of similarity and laplacian matrices: application to galaxy clusters |
we present six vrcic light curves of ux crb from observations carried out from 2011-2015. we also obtained three optical spectra using the 2.16-m optical telescope and lamost survey at the national astronomical observatories. we classified its spectral type as g2±2v. we noticed that there are strong absorptions in the ... | photospheric and chromospheric activity of the short period x-ray and algol eclipsing binary ux crb |
the dawn of the gravitational-wave (gw) era has sparked a greatly renewed interest into possible links between sources of high-energy radiation and gws. the most luminous high-energy sources-gamma-ray bursts (grbs)-have long been considered as very likely sources of gws, particularly from short-duration grbs, which are... | high-energy astrophysics and the search for sources of gravitational waves |
we present the recent results of studies on active galaxies (both agn and starbursts) by the extragalactic group of byurakan astrophysical observatory (bao) research department "astronomical surveys". the research has been carried out in 2017-2019 and the results are published in 2018-2019. these studies are characteri... | studies of active galaxies in byurakan: recent results |
type ia supernovae (sne ia) are the thermonuclear explosions of carbon-oxygen white dwarfs (wds) in binary stellar systems. after many decades of research, the nature of their progenitors is still unclear. there are two main proposed channels: the single-degenerate scenario, where the wd companion is a non-degenerate s... | reconciling models and observations of type ia supernovae and supernova remnants |
it was previously suggested that e ± pair halos could be observed in γ-rays. searching for pair halos is a challenging topic in γ-ray astronomy that has not yet yielded a convincing detection for an individual object. here we propose that x-ray observations could reveal the existence of e ± pair halos. to support our s... | x-rays from e ± pair halos |
ngc 281 is a complex region of star formation at 2.8 kpc. this complex is situated 300 pc above the galactic plane, and appears to be part of a 270 pc diameter ring of atomic and molecular clouds expanding at 22 km/s (megeath et al. 2003). it appears that two modes of triggered star formation are at work here: an initi... | spectroscopic study of ngc 281 west |
spherex, a mission in nasa's medium explorer (midex) program that was selected for phase a study in august 2017, will perform an all-sky near-infrared spectral survey between 0.75 - 5.0 microns. the survey will reach 18.3 ab mag (5 sigma) in r=41 filters, with r=135 coverage between 4.2 - 5.0 microns. the key science t... | spherex: science opportunities for the astronomical community |
we describe a model of tidal disruption events (tdes) with input physical parameters that include the black hole (bh) mass m•, the specific orbital energy e, the angular momentum j, the star mass m⊙ and radius r⊙. we calculate the rise time of the tdes, the peak bolometric luminosity in terms of these physical paramete... | physics and observations of tidal disruption events |
application of cubesats in astronomical observations has been getting more and more mature in recent years. here we report a concept study of a small compton polarimeter to fly on a cubesat for observing polarization of soft gamma-rays from a black-hole x-ray binary, cygnus x-1. polarization states provide very useful ... | concept study of a small compton polarimeter to fly on a cubesat |
we performed h-alpha spectroscopic observations of the be/x-ray binary x per, optical counterpart of the slow x-ray pulsar 4u 0352+30, using the 2.0m telescope of the rozhen national astronomical observatory, bulgaria and the 1.2m tigre telescope located in mexico. | x persei - correlation between h-alpha and x-ray variability |
using the archival data obtained from chandra and suzaku spanning over '8 years, we present an analysis of a wn6h+o4f wolf-rayet binary, wr 25. the x-ray light curves folded over a period of '208 d in the 0.3 - 10.0 kev energy band showed phase-locked variability where the count rates were found to be maximum near the ... | x-ray observations of the colliding wind binary wr 25 |
quark-novae leave behind quark stars with a surrounding metal-rich fall-back (ring-like) material. these compact remnants have high magnetic fields and are misconstrued as magnetars; however, several observational features allow us to distinguish a quark star (l behind by a quark-nova) from a neutron star with high mag... | quark-nova compact remnants: observational signatures in astronomical data and implications to compact stars |
line coincidence photopumping is a process where the electrons of an atomic or molecular species are radiatively excited through the absorption of line emission from another species at a coincident wavelength. there are many instances of line coincidence photopumping in astrophysical sources at optical and ultraviolet ... | x-ray line coincidence photopumping in a solar flare |
the chinese-french space mission svom (space-based multiband astronomical variable objects monitor) is mainly designed to detect and localize gamma-ray burst (grb) events. the satellite, to be launched in late 2021, will carry a set of gamma-ray, x-ray, and optical imagers. thanks to its pointing strategy, quick slew c... | the svom mission. |
this paper presents the results of processing the data on the partial solar eclipse that occurred on march 20, 2015, and was observed with the rt-3 (λ = 4.9 cm) and rt-2 (λ = 3.2 cm) radio telescopes of the kislovodsk mountain astronomical station, central astronomical observatory, russian academy of sciences (mas cao ... | chromospheric and coronal radio sources from observations of the partial solar eclipse of march 20, 2015, at the mountain astronomical station of the central astronomical observatory |
we report our first optical spectropolarimetric observations of the be/x-ray binary lsi+61°303. the observations are performed with the 2.0m telescope of bulgarian national astronomical observatory rozhen on march 18, 2015. we obtain degree of linear polarization pint = 2.36±0.19% and position angle θint = 17°:90±9°.98... | spectropolarimetric observations of the be/x-ray binary star lsi+61°303 |
c2h4o2 isomers, methyl formate (hcooch3), acetic acid (ch3cooh) and glycoaldehyde (hoch2cho), have been detected in a lot of sources in ism. however, their abundances are very different, with methyl formate much more abundant than the other two isomers. this fact may be related to the different destruction by ionizing ... | destruction of c2h4o2 isomers in ice-phase by x-rays: implication on the abundance of acetic acid and methyl formate in the interstellar medium |
the paper provides a description of recent progress in the development of lightweight, precision and highthroughput grazing-incidence mirrors for x-ray astronomy made of glass. in particular, the indirect slumping technology under investigation at the max planck institute for extraterrestrial physics (mpe) is reviewed ... | indirect glass slumping of grazing incidence mirror segments for lightweight x-ray telescopes |
driven by the requirements in synchrotron radiation applications, astronomical observation, and dense plasma diagnostics, the euv, soft x-rays and x-rays multilayer optics have been tremendously developed. based on the lamp project for soft x-ray polarimetry, co/c and cr/c multilayers have been fabricated and character... | multilayers for euv, soft x-ray and x-ray optics |
this paper describes a new variation of the differential deposition/differential erosion technique for mid-frequency surface-height error correction. in our approach, the technique is extended to two dimensions in order to correct surfaceheight errors in thin-shell cylindrical mirror segments with high throughput. we d... | two-dimensional differential deposition: figure correction of thin-shell mirror substrates for x-ray astronomy |
for several years, the max-planck-institute for extraterrestrial physics in germany (mpe) and the astronomical observatory of brera in italy (inaf-oab) have been studying the slumping technology for the manufacturing of segmented glass x-ray optics for astronomy. despite some differences in their specific approaches, t... | jim: a joint integrated module of glass x-ray optics for astronomical telescopes |
this paper presents a new method to model the transverse scattering from random rough surfaces. it uses the same approach as our 2003 spie paper - pz and lvs,1 but considers the scattering in the direction perpendicular to the incident plane. for a given power spectral density, a model surface is constructed by assigni... | transverse x-ray scattering on random rough surfaces |
since the april 2002 first version of the xmm-newton science archive (xsa), the esa science data centre team (esdc) has improved and updated this valuable service to the x-ray astronomical community. based on the absi (archive building system infrastructure), the xsa has a common architecture with the rest of the archi... | xmm-newton science archive (xsa) |
active galactic nuclei (agn) are among the brightest and most frequent sources on the extragalactic x-ray and gamma-ray sky. their central supermassive blackhole generates an enormous luminostiy through accretion of the surrounding gas. a few agn harbor highly collimated, powerful jets in which are observed across the ... | classifying the high-energy sky with spectral and timing methods |
we calculate the x-ray signal that should arise due to reflection of the putative collimated x-ray emission of the galactic supercritical accretor ss 433 on the molecular clouds in its vicinity. the molecular gas distribution in the region of interest has been constructed based on the data of the boston university-five... | constraints on the collimated x-ray emission of ss 433 from the reflection on molecular clouds |
every 10 years, x-ray astronomers gather in bologna, italy, to review the state of the field. after 30 years of these meetings, is there really still a separate field of x-ray astronomy? | x-ray astronomy in 2019 |
recent rapid developments in deep learning, which can implicitly capture structures in high-dimensional data, will lead to the opening of a new chapter of astronomical data analysis. as a new implementation of deep learning techniques in the fields of astronomy, we here report our application of variational auto-encode... | a new implementation of deep neural network for spatio-spectral analysis in x-ray astronomy |
quark-novae leave behind quark stars with a surrounding metal-rich fall-back (ring-like) material. these compact remnants have high magnetic fields and are misconstrued as magnetars; however, several observational features allow us to distinguish a quark star (left behind by a quark-nova) from a neutron star with high ... | quark-nova compact remnants: observational signatures in astronomical data and implications to compact stars |
with the observation of the gravitational wave event of august 17th 2017 and then with those of the extragalactic neutrino of september 22nd, the multi messenger astronomy era has definitely begun. with the opening of this new panorama, it is necessary to have a perfect coordination of the several observatories. crysta... | crystal eye: a wide sight on the universe looking for the electromagnetic counterpart of gravitational waves |
as we have seen for digital camera market and a sensor resolution increasing to "megapixels", all the scientific and high-tech imagers (whatever the wave length - from radio to x-ray range) tends also to always increases the pixels number. so the constraints on front-end signals transmission increase too. an almost una... | front-end multiplexing—applied to squid multiplexing: athena x-ifu and qubic experiments |
this white paper is a summarising report of the forum on monitoring the transient x-ray universe in the multi-messenger era organized by the international space science institute in beijing (issi-bj) on may 6-7, 2014. time-domain astronomy will enter a golden era towards the end of this decade with the advent of major ... | exploring the dynamic x-ray universe (summarising report of the issi-bj forum on monitoring the transient x-ray universe in the multi-messenger era, beijing, may 6-7, 2014) |
it has recently been pointed out that ultra-long gamma-ray bursts (ulgrbs), with very atypical durations of more than 1000 seconds, could form a new class of grbs (levan+13). ulgrbs could have a different progenitor than standard grbs and be produced by the core collapse of a low metallicity supergiant blue star (gendr... | detection capability of ultra-long gamma-ray bursts with the eclairs telescope aboard the svom mission under development |
'what is the science impact of your observatory?' is the dreaded question most observatories face in one way or another. classically, the number of science papers and citation rates of those papers are presented to show the science impact of an observatory with perhaps some download statistics thrown in for good measur... | indicators of the science impact of an observatory |
thanks to incredible advances in instrumentation, surveys like the sloan digital sky survey have been able to find and catalog billions of objects, ranging from local m dwarfs to distant quasars. machine learning algorithms have greatly aided in the effort to classify these objects; however, there are regimes where the... | there are (super)giants in the sky: searching for misidentified massive stars in algorithmically-selected quasar catalogs |
the world's premier x-ray astronomical observatories, chandra and xmm-newton, have been operating for about 20 years. the next flagship x-ray observatory launched will be esa's athena mission. we discuss planned us contributions to the athena wide field imager instrument, which encompass transient source detection, bac... | us contributions to the athena wide field imager |
the infrared astronomical satellite akari conducted deep (∼0.4 deg2) and wide (∼ 5.4 deg2) surveys around the north ecliptic pole (nep) with its infrared camera (irc) with nine filters continuously covering the 2-25 μm range. these photometric bands include three filters that fill the " spitzer gap" between the wavelen... | x-ray - infrared relation of agns and search for highly obscured accretion in the akari nep field |
we analyzed the microwave radiation of the sun observed on radio telescopes of the kislovodsk astronomical station rt-3 (4.9 cm) and rt-2 (3.2 cm). comparisons of long series of observations with observations on other radio instruments and also in the optical and x-ray ranges have been made. a study is made of the fore... | forecast of solar flares from observations in the microwave range at the kislovodsk station |
through out the ancient history, chinese astronomers had made tremendous achievements. since the main purpose of the ancient chinese astronomy was to study the correlation between man and the universe, all the emperors made ancient chinese astronomy the highly regarded science throughout the history. after a brief intr... | past, present and future of chinese astronomy |
we are presenting a novel concept for a fully depleted, monolithic, pinned photodiode cmos image sensor using reverse substrate bias. the principle of operation allows the manufacture of backside illuminated cmos sensors with active thickness in excess of 100 μm. this helps increase the qe at near-ir and soft x-ray wav... | fully depleted and backside biased monolithic cmos image sensor |
the australian ska pathfinder (askap) is an array of 36 antennas under construction in western australia. it is designed as a survey instrument for extensive radio astronomy surveys of the southern sky. askap is a data driven facility where the data rates are extremely high. in full operations the volume of archived da... | casda: the csiro askap science data archive |
in this thesis, we studied physical and evolutionary aspects of the intergalactic medium throughout the universe. we used the archived subaru telescope data and measured the ionization radiation escape fraction of 207 lyalpha emitting galaxies at z ≃ 3.3 in the sxds field which does not contain any known overdensity re... | the ionized intergalactic medium and its influence on galaxies and galaxy clusters |
sifap: a simple sub-millisecond astronomical photometer (ambrosino et al.: 2013, j. astron. instrum. vol. 2 (01), 1350006; ambrosino et al.: 2014, proc of the spie, 9147, 91478r) has been used at the cassegrain focus of the g.d. cassini 152 cm loiano telescope in order to detect possible short term periodicities and/or... | milli-second optical observations of v 404 cyg with sifap |
thin glass mirrors are a viable solution to build future x-ray telescopes with high angular resolution and large collecting area. this approach is very attractive for the optics implementation of future x-ray astronomy projects like the x-ray surveyor missions in usa, the xtp mission in china and the force mission in j... | slumped glass optics development with pressure assistance |
adjustable x-ray optics represent a potential enabling technology for simultaneously achieving large effective area and high angular resolution for future x-ray astronomy missions. the adjustable optics employ a bimorph mirror composed of a thin (1.5 μm) film of piezoelectric material deposited on the back of a 0.4 mm ... | using iridium films to compensate for piezo-electric materials processing stresses in adjustable x-ray optics |
since the discovery of cosmic rays, earth's upper atmosphere at depths of 1-10 g cm-2 has been used for balloon-borne observations probing the high-energy universe. however, the interaction of cosmic rays with the earth atmosphere generates numerous particles, each with their own flux and interaction physics that contr... | modern assessment of the high-energy background environment at small atmospheric depths using the x-calibur x-ray polarimeter and its implications |
five characteristics determine the utility of an x-ray optics technology for astronomy: (1) angular resolution, (2) field of view, (3) energy bandwidth, (4) mass per unit photon collecting area, and (5) production cost per unit photon collecting area. these five desired characteristics are always in conflict with each ... | toward diffraction-limited lightweight x-ray optics for astronomy |
observations of solar active regions (ars) in the soft x-ray spectral range (0.5 to 3.0 nm) were made on sounding rocket flight nasa 36.290 using a modified solar aspect monitor (sam), a pinhole camera on the euv variability experiment (eve) sounding rocket instrument. the suite of eve rocket instruments is designed fo... | active region soft x-ray spectra as observed using sounding rocket measurements from the solar aspect monitor (sam), - a modified sdo/eve instrument |
consistent improvements in the design and fabrication of thin-foil, epoxy-replicated x-ray mirrors for astronomical telescopes have yielded increasingly higher quality and more precise astrophysical data. the neutron star interior composition explorer (nicer) x-ray timing mission optics continues this tradition and int... | shrink tape technique for heat-forming aluminum substrates for thin foil x-ray mirrors and the neutron star interior composition explorer x-ray concentrators |
pyxel is an new python package for modeling astronomical x-ray imaging data. it is built on numpy, scipy, matplotlib, and astropy, and distributed under an open-source license. the package aims to provide a common set of image analysis tools for astronomers working with extended x-ray sources. i will present an overvie... | pyxel: a python package for astronomical x-ray data modeling |
we describe an approach to building mirror assemblies for next generation x-ray telescopes. it incorporates knowledge and lessons learned from building existing telescopes, including chandra, xmm-newton, suzaku, and nustar, as well as from our direct experience of the last 15 years developing mirror technology for the ... | lightweight and high-resolution single crystal silicon optics for x-ray astronomy |
c. knigge (university of southampton) et al. announce (atel #7735) that far-ultraviolet (fuv) and near-ultraviolet (nuv) spectroscopic observations of the black hole x-ray transient lmxb v404 cyg with the hubble space telescope have been scheduled for 2015 july 10, 11, and 12 at the satellite's earliest availability, a... | v404 cyg hst multiwavelength observations scheduled |
when the most massive stars perish, their cores may remain intact in the form of extremely dense and compact stars. these stellar remnants, called neutron stars, are on the cusp of becoming black holes and reach mass densities greater than an atomic nucleus in their centers. although the interiors of neutron stars were... | starquakes, heating anomalies, and nuclear reactions in the neutron star crust |
we present the results of an analysis of the archival xmm-newton epic data (203ks for pn and 556/574ks for mos1/mos2) and the chandra x-ray observatory acis data (89ks) of the brightest x-ray supernova remnant (snr) in the large magellanic cloud (lmc) n132d. n132d has been classified as an ``o-rich'' remnant based on t... | n132d: chandra and xmm-newton x-ray imaging and spectral analysis |
with the high sensitivity and wide-field coverage of the square kilometre array (ska), large samples of explosive transients are expected to be discovered. radio wavelengths, especially in commensal survey mode, are particularly well-suited for uncovering the complex transient phenomena. this is because observations at... | explosive and radio-selected transients: transient astronomy with square kilometre array and its precursors |
we describe the initial in-orbit operations and performance of the astro-h soft x-ray spectrometer (sxs). astro-h, jaxa's sixth x-ray observatory, is scheduled for launch on february 12, 2016, from the tanegashima space center in japan abord an h-iia rocket. the instrument is based on a 36-pixel array of microcalorimet... | progress report on the astro-h soft x-ray spectrometer |
the assumption that neutron stars have hadronic crusts, when coupled with the assumptions of causality and that gr is the correct theory of gravity, places interesting constraints on their structural properties, including the maximum mass and their typical radii, moments of inertia and binding energies. with additional... | perspectives on the equation of state in neutron stars |
this thesis focuses on high-mass x-ray binaries (hmxbs) and their gamma-ray precursors, consisting of a compact object and an optical companion. matter lost from the companion is accreted by the compact-object where the gravitational potential energy is converted into x-ray radiation. the predominant high-energy emissi... | probing the structure and morphology of x-ray and gamma-ray binaries using a multi-wavelength, multi-mission approach |
the mechanisms behind core-collapse supernovae represent one of the most important unsolved problems in stellar astrophysics and are of interest to many branches of physics and astronomy, such as nucleosynthesis, pulsar formation, gamma-ray bursts, and gravitational wave production. few direct observational constraints... | the 3d distribution of 44-ti in cassiopeia a |
observations of molecules in planet-forming circumstellar disks are powerful diagnostic tools, enabling characterization of both gas composition and underlying physical conditions using molecular excitation. my thesis has primarily focused on the role of disk structure and ionization for the chemistry of disks and the ... | molecular signposts of the physics and chemistry of planet formation |
observations at a frequency of 111 mhz with the large phased array at the pushchino radio astronomy observatory of the astro space center of the p.n. lebedev physical institute confirm the pulsed radio emission of the x-ray pulsar j1907+0919 that is a counterpart of the magnetar sgr 1900+14. its pulsed radio emission w... | confirmation of pulsed radio emission from the pulsar j1907+0919 (shitov radio pulsar, sgr 1900+14) |
the boom in ground-based gamma-ray astronomy since the beginning of the 21st century has enabled a new probe of the universe using very-high-energy photons. the very energetic radiation imaging telescope array system (veritas) is an array of four 12-m imaging cherenkov telescopes that is sensitive to gamma rays in the ... | observations of variability of tev gamma-ray blazars |
relatively massive b-type stars with closely orbiting stellar companions can evolve to produce type ia supernovae, x-ray binaries, millisecond pulsars, mergers of neutron stars, gamma ray bursts, and sources of gravitational waves. however, the formation mechanism, intrinsic frequency, and evolutionary processes of b-t... | how i learned to stop worrying and love eclipsing binaries |
the international workshop on quark phase transition in compact objects and multimessenger astronomy: neutrino signals, supernovae and gamma-ray bursts (october, 7-14, 2015) was dedicated to quantum chromodynamics (qcd) phase transitions and observational signals of these transitions related to formation of compact ast... | quark phase transition in compact objects and multimessenger astronomy: neutrino signals, supernovae and gamma-ray bursts |
solar flares can release 1e33 ergs of power, accelerate particles to relativistic speeds, heat plasma to 15 million k and catastrophically reorganize 1e5 km long field structures in 100s-1000s of seconds. magnetic reconnection of large-scale field structures in the corona are thought to power flares, but the precise me... | gamma-ray observations of solar flares with rhessi imaging spectroscopy and the grips instrument |
i discuss some of what is known and unknown about the behavior of black hole binary systems in the quiescent accretion state. quiescence is important for several reasons: 1) the dominance of the companion star in optical and ir wavelengths allows the binary parameters to be robustly determined - as an example, we argue... | black hole binaries in quiescence |
the lamp (lightweight asymmetry and magnetism probe) x-ray telescope is a mission concept to measure the polarization of x-ray astronomical sources at 250 ev via imaging mirrors that reflect at incidence angles near the polarization angle, i.e., 45 deg. hence, it will require the adoption of multilayer coatings with a ... | testing multilayer-coated polarizing mirrors for the lamp soft x-ray telescope |
athena is the second large mission selected in the esa cosmic vision plan. with its large collecting area, high spectral-energy resolution (x-ifu instrument) and impressive grasp (wfi instrument), athena will truly revolutionise x-ray astronomy. the most prodigious sources of high-energy photons are often transitory in... | studying the high redshift universe with athena |
xmm-newton has carried out pointed observations of the x-ray sky for more than a decade. the xmm-newton serendipitous source catalog is ultimately intended to be the definitive catalog of x-ray sources that it detected. the newly released version 3xmm-dr5 is 60% larger than its predecessor 2xmmi-dr3 and contains 565,96... | understanding the nature of xmm-newton serendipitous x-ray sources |
the standard approach to model fitting in x-ray astronomy is by means of local optimization methods. however, these local optimizers suffer from a number of problems, such as a tendency for the fit parameters to become trapped in local minima, and can require an involved process of detailed user intervention to guide t... | autonomous modelling of x-ray spectra using robust global optimization methods |
thermonuclear burning of hydrogen on white dwarfs (wds) is an inevitable occurence for accreting wds in binary systems. after the onset of thermally-unstable nuclear burning, the wd rapidly expands and ejects much of its hydrogen-rich matter. once it regains thermal equilibrium, it contracts and becomes a luminous sour... | supersoft emission from thermonuclear burning on hydrogen-accreting white dwarfs |
we develop a formal procedure for the automated recognition of rational and elliptic curves in medical and astronomical images. the procedure is based on the extension of the hough transform concept to the definition of hough transform of special classes of algebraic curves. we first introduce a catalogue of curves tha... | profile detection in medical and astronomical images by means of the hough transform of special classes of curves |
future x-ray astronomy observatories will employ high-speed silicon-based active pixel sensors to obtain wide fields of view with good radiation hardness and low levels of detector saturation (pileup). detector readout rates envisioned for missions such as athena and x-ray surveyor are far too high for existing softwar... | fast event recognition for x-ray silicon imagers |
over the last 50 years, x-ray astronomy has become firmly established as an essential window on the universe. we review some selected scientific highlights based on observations made with xmm-newton during the most recent few years of its 16-year operation. these range from studies of objects in our solar system to top... | xmm-newton: status and scientific perspective |
radio astronomy is going through major changes and new radio telescopes are coming online, paving the way to the square kilometre array (ska). their new capabilities—e.g., large field of view combined with good spatial resolution, broad instantaneous band, and fast response to transient objects—offer unique possibiliti... | synergy with new radio facilities: from lofar to ska |
smile is a novel space mission, under development, dedicated to study the dynamic coupling of the solar wind with the earth's magnetosphere in a global way never attempted before. from a highly elliptical earth orbit smile will obtain x-ray images of the magnetosheath and polar cusps simultaneously with uv images of th... | smile (solar wind magnetosphere ionosphere link explorer): x-ray imaging of the sun-earth connection |
chains of type i are associated with the radio noise storms (rns). we report the analysis of the parameters of the two rns: one associated with the occurrence of solar flares in x-rays and one recorded on a day without the presence of a flare. the spectral information about the chains in these events were obtained from... | parameters of type i chains and their association with flares in x-ray |
presented herein is an x-ray study of the variable point sources in the local starburst galaxy ic 10, gathered from 10 chandra x-ray telescope observations spanning from 2003 to 2010. the observations reach a limiting luminosity of 1035 ergs -1 implying sensitivity to x-ray binaries within ic 10. x-ray spectra are pres... | a chandra study of the variable x-ray population in the local starburst galaxy ic 10 |
blazars are a rare class of active galactic nucleus (agn) with relativistic jets closely aligned with the line of sight. many aspects of the environments and kiloparsec-scale jet structure are not fully understood. hybrid and high synchrotron peaked (hsp) blazars are two types of blazar that provide unique opportunitie... | kiloparsec jet properties of hybrid, low-, and high-synchrotron-peaked blazars |
high-mass x-ray binaries (hmxbs) consist of a black hole or neutron star accreting material from a high-mass stellar companion. although these systems are very rare, with only about 100 having been discovered in the milky way galaxy, they provide crucial insights into the evolution of high-mass stars and may have playe... | the faint, the poor, and the steady: studies of low-luminosity, metal-poor, and non-pulsating populations of high-mass x-ray binaries |
we report the first detection of the sunyaev-zel'dovich (sz) signature of cavities in the intracluster medium (icm) associated with radio-mechanical feedback from an active galactic nucleus (agn) in the center of a galaxy cluster. such cavities are seen as regions of reduced brightness in x-ray images; while this reduc... | probing agn-inflated cavities in galaxy cluster ms 0735+74 with the sunyaev-zel'dovich effect |
dr. leisa townsley (1964-2022) was a talented and remarkable scientist, and the astronomical community was shocked to learn of her passing in august 2022. this talk and session are dedicated to her memory. dr. townsley served as a leader within the penn state chandra acis instrument team for more than 28 years, includi... | a dedication to dr. leisa townsley |
a brief history of x-ray astronomy is presented, followed by a summary of some of the highlights of various chapters of the book: a description of chandra and its operations, mechanisms for the production and absorption of x-rays in a cosmic setting, x-rays from stars and planets, supernovae and their remnants, x-ray b... | introduction |
the anticipated xrism launch next year will provide a plethora of new x-ray observations of the universe. the limited data from hitomi highlights the need for more laboratory data to complement the anticipated new observations. in this proposal to the sub-element laboratory astrophysics, we aim to deepen our understand... | experimental and theoretical investigation of velocity dependent ion-atom charge exchange with coincident x-ray spectroscopy |
toward a new 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 less than 1 arcmin, we are developing micropore x-ray optics based on micromaching technologies. using sidewalls of micropores through a ... | small satellites with mems x-ray telescopes for x-ray astronomy and solar system exploration |
this article presents a short and concise survey on prime graphs. the field of graph theory plays a vital role in various fields. one of the important areas in graph theory is graph labeling used in many applications like “coding theory, x - ray crystallography, radar, astronomy, circuit design, communication network a... | a comprehensive survey on prime graphs |
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