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herein, we present results from observations of the 12co (j = 1-0), 13co (j = 1-0), and 12co (j = 2-1) emission lines toward the carina nebula complex (cnc) obtained with the mopra and nanten2 telescopes. we focused on massive-star-forming regions associated with the cnc including the three star clusters tr 14, tr 15, ... | massive star formation in the carina nebula complex and gum 31. i. the carina nebula complex |
we present a broadband x-ray study of w50 (the "manatee" nebula), the complex region powered by the microquasar ss 433, that provides a test bed for several important astrophysical processes. the w50 nebula, a galactic pevatron candidate, is classified as a supernova remnant but has an unusual double-lobed morphology l... | hard x-ray emission from the eastern jet of ss 433 powering the w50 "manatee" nebula: evidence for particle reacceleration |
after more than 26 years in quiescence, the black hole transient v404 cyg went into a luminous outburst in 2015 june, and additional activity was detected in late december of the same year. here, we present an optical spectroscopic follow-up of the december mini-outburst, together with x-ray, optical and radio monitori... | flares, wind and nebulae: the 2015 december mini-outburst of v404 cygni |
evidence for the capture of nebular gases by planetary interiors would place important constraints on models of planet formation. these constraints include accretion timescales, thermal evolution, volatile compositions and planetary redox states1-7. retention of nebular gases by planetary interiors also constrains the ... | capture of nebular gases during earth's accretion is preserved in deep-mantle neon |
the isotopic composition of oxygen as well as 26al-26mg and 36cl-36s systematics were studied in curious marie, an aqueously altered allende cai characterized by a group ii ree pattern and a large 235u excess produced by the decay of short-lived 247cm. oxygen isotopic compositions in the secondary minerals of curious m... | in situ isotopic studies of the u-depleted allende cai curious marie: pre-accretionary alteration and the co-existence of 26al and 36cl in the early solar nebula |
synchrotron emission from astrophysical nonthermal sources usually assumes that the emitting particles are isotropic. by means of large-scale two- and three-dimensional particle-in-cell simulations, we demonstrate that the dissipation of magnetically dominated ( ${\sigma }_{0}\gg 1$ ) turbulence in pair plasmas leads t... | hard synchrotron spectra from magnetically dominated plasma turbulence |
we have measured variations in scattering time-scales in the crab pulsar over a 30-yr period, using observations made at 610 mhz with the 42-ft telescope at jodrell bank observatory. over more recent years, where regular lovell telescope observations at frequencies around 1400 mhz were available, we have also determine... | temporal variations in scattering and dispersion measure in the crab pulsar and their effect on timing precision |
red supergiants have been confirmed as the progenitor stars of the majority of hydrogen-rich type ii supernovae1. however, while such stars are observed with masses >25 m⊙ (ref. 2), detections of >18 m⊙ progenitors remain elusive1. red supergiants are also expected to form at all metallicities, but discoveries of... | the lowest-metallicity type ii supernova from the highest-mass red supergiant progenitor |
as the closest type ia supernova in decades, sn 2014j provides a unique opportunity for detailed investigation into observational signatures of the progenitor system, explosion mechanism, and burning product distribution. we present a late-time near-infrared spectral series from gemini-n at 307{--}466 {days} after the ... | near-infrared spectral evolution of the type ia supernova 2014j in the nebular phase: implications for the progenitor system |
we investigate the dynamics of dust grains of various sizes in protoplanetary disk winds driven by magnetorotational turbulence, by simulating the time evolution of the dust grain distribution in the vertical direction. small dust grains, which are well-coupled to the gas, are dragged upward with the upflowing gas, whi... | dust dynamics in protoplanetary disk winds driven by magnetorotational turbulence: a mechanism for floating dust grains with characteristic sizes |
the first bright objects to form in the universe at redshift $z \sim 10-20$ might have been dark stars, made primarily of hydrogen and helium but powered by dark matter. in this study, we investigate the detectability of supermassive dark stars (smds) by the roman space telescope. rst will be able to detect smdss at re... | detectability of supermassive dark stars with the roman space telescope |
we report on the source gaia 19ajj, identifying it as a young star associated with a little-studied star-forming region seen along a complex line of sight through the gum nebula. the optical lightcurve recently recorded by gaia exhibits a slow and unsteady 5.5 mag rise over about 3 yr, while the mid-infrared lightcurve... | gaia 19ajj: a young star brightening due to enhanced accretion and reduced extinction |
we explore the role that gravitational instability plays in ngc 1068, a nearby seyfert galaxy that exhibits unusually vigorous starburst activity. for this purpose, we use the romeo-falstad disc instability diagnostics and data from the bima survey of nearby galaxies, the sloan digital sky survey and the spectrographic... | what powers the starburst activity of ngc 1068? star-driven gravitational instabilities caught in the act |
in the years to come, the javalambre-physics of the accelerated universe astrophysical survey (j-pas) will observe 8000 deg2 of the northern sky with 56 photometric bands. j-pas is ideal for the detection of nebular emission objects. this paper presents a new method based on artificial neural networks (anns) that is ai... | j-pas: measuring emission lines with artificial neural networks |
the rate at which interstellar gas is converted into stars, and its dependence on environment, is one of the pillars on which our understanding of the visible universe is build. we present a comparison of the surface density of young stars (σ⋆) and dust surface density (σdust) across ngc 346 (n66) in 115 independent pi... | star formation rates from young-star counts and the structure of the ism across the ngc 346/n66 complex in the smc |
context. in a recent study, star-forming galaxies with he ii λ1640 emission at moderate redshifts between 2 and 4.6 have been found to occur in two modes that are distinguished by the width of their he ii emission lines. broad he ii emission has been attributed to stellar emission from a population of evolved wolf-raye... | narrow he ii emission in star-forming galaxies at low metallicity. stellar wind emission from a population of very massive stars |
we investigate the intrinsic stellar populations (estimated total numbers of ob and pre-main-sequence stars down to 0.1 {{m}⊙ }) that are present in 17 massive star-forming regions (msfrs) surveyed by the mystix project. the study is based on the catalog of >31,000 mystix probable complex members with both disk-bear... | the spatial structure of young stellar clusters. ii. total young stellar populations |
we use spatially extended measurements of lyα as well as less optically thick emission lines from an ≈80 kpc lyα nebula at z ≈ 1.67 to assess the role of resonant scattering and to disentangle kinematic signatures from lyα radiative transfer effects. we find that the lyα, c iv, he ii, and c iii] emission lines all tell... | spatially resolved gas kinematics within a lyα nebula: evidence for large-scale rotation |
aims: we measure the crab nebula γ-ray spectral energy distribution in the ~100 tev energy domain and test the validity of existing leptonic emission models at these high energies.methods: we used the novel very large zenith angle observations with the magic telescope system to increase the collection area above 10 tev... | magic very large zenith angle observations of the crab nebula up to 100 tev |
in this paper we examine the direct method for measuring electron temperatures in h ii regions, and the extent to which such measurements can provide meaningful information on the physical conditions in these regions. we discuss the limits to what can be inferred about electron temperatures from nebular emission line f... | estimating electron temperatures in ionized nebulae: the direct method and its limitations |
we present the results of a wide spectroscopic survey aimed at detecting extragalactic globular clusters (gcs) in the core of the fornax cluster. about 4500 low-resolution spectra (from 4800 to 10000 å) were observed in 25 vlt/vimos masks covering the central 1 deg2 around the dominant galaxy ngc 1399 corresponding to ... | the fornax cluster vlt spectroscopic survey - i. vimos spectroscopy of compact stellar systems in the fornax core region |
infrared observations of the dusty, massive homunculus nebula around the luminous blue variable η carinae are crucial to characterize the mass-loss history and help constrain the mechanisms leading to the great eruption. we present the 2.4-670 μm spectral energy distribution, constructed from legacy infrared space obse... | η carinae's dusty homunculus nebula from near-infrared to submillimeter wavelengths: mass, composition, and evidence for fading opacity |
we studied the pevatron nature of the pulsar wind nebula (pwn) g75.2+0.1 ("dragonfly") as part of our nustar observational campaign of energetic pwne. the dragonfly is spatially coincident with lhaaso j2018+3651, whose maximum photon energy is 0.27 pev. we detected a compact (radius $1^{\prime} $ ) inner nebula of the ... | hard x-ray observation and multiwavelength study of the pevatron candidate pulsar wind nebula "dragonfly" |
compound chondrules, i.e. chondrules fused together, make a powerful probe of the density and compositional diversity in chondrule-forming environments, but their abundance among the dominating porphyritic textures may have been drastically underestimated. i report herein microscopic observations and la-icp-ms analyses... | collisions and compositional variability in chondrule-forming events |
we have been undertaking a systematic survey at 850 μm based on a sample of four prototypical z ∼ 2 − 3 enormous lyα nebulae (elane) as well as their megaparsec-scale (mpc-scale) environments to study the physical connections between elane and their coeval dusty submillimeter galaxies (smgs). by analysing the scuba-2 d... | a multiwavelength study of elan environments (amuse2). ubiquitous dusty star-forming galaxies associated with enormous lyα nebulae on megaparsec scales |
direct observations of low-mass, low-metallicity galaxies at z ≳ 4 provide an indispensable opportunity for detailed inspection of the ionization radiation, gas flow, and metal enrichment in sources similar to those that reionized the universe. combining the james webb space telescope (jwst), very large telescope/muse,... | metal-enriched neutral gas reservoir around a strongly lensed low-mass galaxy at z = 4 identified by jwst/niriss and vlt/muse |
pulsar wind nebula (pwn) boomerang and the associated supernova remnant (snr) g106.3+2.7 are among candidates for the ultra-high-energy (uhe) gamma-ray counterparts published by lhaaso. although the centroid of the extended source, lhaaso j2226+6057, deviates from the pulsar's position by about 0.3∘, the source partial... | a pevatron candidate: modeling the boomerang nebula in x-ray band |
we present accretion-disk structure measurements from uv-optical reverberation mapping (rm) observations of a sample of eight quasars at 0.24 < z < 0.85. ultraviolet photometry comes from two cycles of hubble space telescope monitoring, accompanied by multiband optical monitoring by the las cumbres observatory ne... | the sloan digital sky survey reverberation mapping project: uv-optical accretion disk measurements with the hubble space telescope |
we present an extensive, panchromatic photometric (uv, optical, and near-ir) and low-resolution optical spectroscopic coverage of a type iip supernova sn 2018gj that occurred on the outskirts of the host galaxy ngc 6217. from the v-band light curve, we estimate the plateau length to be ~ 70 ± 2 days, placing it among t... | sn 2018gj: a short plateau type ii supernova with persistent blueshifted ha emission |
we present high-cadence photometric and spectroscopic observations of sn 2020jfo in ultraviolet and optical/near-infrared bands starting from ~3 to ~434 d after the explosion, including the earliest data with the 10.4-m gtc. sn 2020jfo is a hydrogen-rich type ii sn with a relatively short plateau duration (67.0 ± 0.6 d... | photometric and spectroscopic analysis of the type ii sn 2020jfo with a short plateau |
if the envelope of a massive star is not entirely removed during common envelope (ce) interaction with an orbiting compact (e.g., black hole (bh) or neutron star (ns)) companion, the residual bound material eventually cools, forming a centrifugally supported disk around the binary containing the stripped he core. we pr... | long-term evolution of massive-star post-common-envelope circumbinary disks and the environments of fast luminous transients |
the observed diversity in type ia supernovae (sne ia) - the thermonuclear explosions of carbon-oxygen white dwarf stars used as cosmological standard candles - is currently met with a variety of explosion models and progenitor scenarios. to help improve our understanding of whether and how often different models contri... | nebular-phase spectra of type ia supernovae from the las cumbres observatory global supernova project |
the systematic targeting of extended lyα emission around high-redshift quasars resulted in the discovery of rare and bright enormous lyα nebulae (elane) associated with multiple active galactic nuclei (agns). we initiate here "a multiwavelength study of elan environments" (amuse2) focusing on the elan around the z ~ 3 ... | a multiwavelength study of elan environments (amuse2). mass budget, satellites spin alignment, and gas infall in a massive z 3 quasar host halo |
we derive a catalog of early-type emission-line stars including 30,023 spectra of 25,867 stars from lamost data release 7, in which 4189 have simbad records. the spectra are classified into three morphological types (10 subtypes) based on hα emission-line profiles. some spectra contaminated by nebula emission lines suc... | a catalog of early-type hα emission-line stars and 62 newly confirmed herbig ae/be stars from lamost data release 7 |
we present alma observations of the orion nebula that cover the omc1 outflow region. our focus in this paper is on compact emission from protoplanetary disks. we mosaicked a field containing ∼600 near-ir-identified young stars, around which we can search for sub-millimeter emission tracing dusty disks. approximately 10... | protoplanetary disks in the orion omc1 region imaged with alma |
al-mg mineral isochrons of three ca-al-rich inclusions (cais) that formed primarily by condensation, one fine-grained, spinel-rich inclusion and two fluffy type a cais, from the reduced cv chondrites efremovka and vigarano were obtained by in situ al-mg isotope measurements using secondary ion mass spectrometry. the sl... | variations in initial 26al/27al ratios among fluffy type a ca-al-rich inclusions from reduced cv chondrites |
cool (t ~ 104 k) gas is commonly observed around z > 2 quasars as traced by extended lyα emission. these large-scale nebulae are usually studied using circularly averaged surface-brightness profiles, which suppress information on morphological differences. here, we revisit the lyα nebulae around 78 z ~ 2-3 quasars t... | the luminosity-area relation of z > 2 quasars' lyα nebulae |
the nucleosynthetic mo, ru, and w isotopic compositions of the south byron trio iron meteorite grouplet (sbt) are consistent with all three meteorites originating on a single parent body that formed in the carbonaceous chondrite (cc) isotopic domain within the solar nebula. consistent with a common origin, the highly s... | genetics, crystallization sequence, and age of the south byron trio iron meteorites: new insights to carbonaceous chondrite (cc) type parent bodies |
we present a spectroscopic survey of over 3400 potential members in the north america and pelican nebulae (nap) using several low-resolution (r ≈ 1300-2000) spectrographs: palomar/norris, wiyn/hydra, keck/deep imaging multi-object spectrograph (deimos), and the multiple mirror telescope (mmt)/hectospec. we identify 580... | the first extensive spectroscopic study of young stars in the north america and pelican nebulae |
fine-grained rims (fgrs) are ubiquitous in chondrites. they consist of unequilibrated mineral assemblages that surround chondrules and refractory inclusions. as such, they carry information about the material that was accreted onto chondrules. to decipher the nature and the formation mechanism of fgrs and compare them ... | nebular thermal processing of accretionary fine-grained rims in the paris cm chondrite |
it has recently been established that unsaturated water-soluble organic compounds (uwsocs) might efficiently form oligomers in polluted fogs and wet aerosol particles, even for weakly soluble ones like methyl vinyl ketone (mvk). the atmospheric relevance of these processes is explored by means of multiphase process mod... | aqueous-phase oligomerization of methyl vinyl ketone through photooxidation - part 1: aging processes of oligomers |
the spectral energy distribution of a galaxy emerges from the complex interplay of many physical ingredients, including its star formation history (sfh), metallicity evolution, and dust properties. using galaxpy, a new galaxy spectral prediction tool, and sfhs predicted by the empirical model universemachine and the co... | surrogate modelling the baryonic universe - i. the colour of star formation |
x-ray earth occultation sounding (xeos) is an emerging method for measuring the neutral density in the lower thermosphere. in this paper, the x-ray earth occultation (xeo) of the crab nebula is investigated using the hard x-ray modulation telescope (insight-hxmt). the pointing observation data on the 30 september 2018 ... | measurement of the vertical atmospheric density profile from the x-ray earth occultation of the crab nebula with insight-hxmt |
the origin and abundance of mantle volatiles present major questions for earth's evolution. here we quantify volatile capture from an atmosphere derived from the solar nebula during accretion, using a boundary layer model of magma ocean dynamics coupled to a nebular atmosphere model adapted to earth formation. key elem... | nebular atmosphere to magma ocean: a model for volatile capture during earth accretion |
magnetic reconnection is a key process that explosively accelerates charged particles, generating phenomena such as nebular flares1, solar flares2 and stunning aurorae3. in planetary magnetospheres, magnetic reconnection has often been identified on the dayside magnetopause and in the nightside magnetodisc, where thin-... | rotationally driven magnetic reconnection in saturn's dayside |
we present a new method to derive oxygen and carbon abundances using the ultraviolet (uv) lines emitted by the gas phase ionized by massive stars. the method is based on the comparison of the nebular emission-line ratios with those predicted by a large grid of photoionization models. given the large dispersion in the o... | using photo-ionisation models to derive carbon and oxygen gas-phase abundances in the rest uv |
context. m49 (ngc 4472) is the dominant galaxy in subcluster b of the virgo cluster, and a benchmark for studying the build-up of the extended halos of brightest group galaxies in the outskirts of galaxy clusters.aims: we investigate the kinematics in the outer halo of m49, look for substructures, and describe the tran... | three dynamically distinct stellar populations in the halo of m49 |
how very young massive star clusters (vymcs; also known as "starburst" clusters), which typically are of ≳ 104 m ⊙ and are a few myr old, form out of giant molecular clouds is still largely an open question. increasingly detailed observations of young star clusters and star-forming molecular clouds and computational st... | formation of very young massive clusters and implications for globular clusters |
we present the discovery of a 3h5m orbital-period binary star at the heart of the planetary nebula m 3-1 - the shortest period photometrically variable central star known and second only to v458 vul, in general. combined modelling of light and radial velocity curves reveals both components to be close to roche lobe fil... | the short orbital period binary star at the heart of the planetary nebula m 3-1 |
as part of the ongoing effort to characterize the low-mass (sub)stellar population in a sample of massive young clusters, we have targeted the ∼2 myr old cluster ngc 2244. the distance to ngc 2244 from gaia dr2 parallaxes is 1.59 kpc, with errors of 1% (statistical) and 11% (systematic). we used the flamingos-2 near-in... | looking deep into the rosette nebula’s heart: the (sub)stellar content of the massive young cluster ngc 2244 |
saturn formed beyond the snow line in the primordial solar nebula, and that made it possible for it to accrete a large mass. disk instability and core accretion models have been proposed for saturn's formation, but core accretion is favored on the basis of its volatile abundances, internal structure, hydrodynamic model... | the origin and evolution of saturn, with exoplanet perspective |
context. in very young clusters, stellar age distribution is empirical proof of the duration of star cluster formation and thus it gives indications of the physical mechanisms involved in the star formation process. determining the amount of interstellar extinction and the correct reddening law are crucial steps to der... | the gaia-eso survey: age spread in the star forming region ngc 6530 from the hr diagram and gravity indicators |
we present extensive optical photometric and spectroscopic observations of the high-velocity (hv) type ia supernova (sn ia) 2017fgc, covering the phase from ~12 days before to ~389 days after maximum brightness. sn 2017fgc is similar to normal sne ia, with an absolute peak magnitude of ${m}_{\max }^{b}\approx $ -19.32 ... | sn 2017fgc: a fast-expanding type ia supernova exploded in massive shell galaxy ngc 474 |
in this work, we propose a proper plasma analysis practice (ppap), an updated procedure of plasma diagnostics in the era of spatially resolved spectroscopy. in particular, we emphasize the importance of performing both of the extinction correction and the direct method of plasma diagnostics simultaneously as an integra... | proper plasma analysis practice (ppap), an integrated procedure of extinction correction and plasma diagnostics: a demo with an hst/wfc3 image set of ngc 6720 |
context. planet traps and snow lines are structures that may promote planetary formation in protoplanetary disks. they are very sensitive to the disk density and temperature structure. it is therefore necessary to follow the time evolution of the disk thermal structure throughout its viscous spreading. since the snowli... | time evolution of snow regions and planet traps in an evolving protoplanetary disk |
circumplanetary disks (cpds) control the growth of planets, supply material for satellites to form, and provide observational signatures of young forming planets. we have carried out two-dimensional hydrodynamical simulations with radiative cooling to study cpds and suggested a new mechanism to drive the disk accretion... | shock-driven accretion in circumplanetary disks: observables and satellite formation |
we present the largest and most spatially extended planetary nebulae (pne) catalogue ever obtained for the fornax cluster. we measured velocities of 1452 pne out to 200 kpc in the cluster core using a counter-dispersed slitless spectroscopic technique with data from fors2 on the very large telescope (vlt). with such an... | the fornax cluster vlt spectroscopic survey ii - planetary nebulae kinematics within 200 kpc of the cluster core |
supernova (sn) 2008bk is a well-observed low-luminosity type ii event visually associated with a low-mass red-supergiant progenitor. to model sn 2008bk, we evolve a 12 m⊙ star from the main sequence until core collapse, when it has a total mass of 9.88 m⊙, a he-core mass of 3.22 m⊙ and a radius of 502 r⊙. we then artif... | a study of the low-luminosity type ii-plateau supernova 2008bk |
we present late-time (∼240-260 days after peak brightness) optical photometry and nebular (+236 and +264 days) spectroscopy of sn 2018oh, the brightest supernova (sn) ia observed by the kepler telescope. the kepler/k2 30 minute cadence observations started days before explosion and continued past peak brightness. for s... | nebular spectroscopy of kepler’s brightest supernova |
calcium-aluminum-rich inclusions (cais) are the first solids to form in the early solar system, and they exhibit nucleosynthetic anomalies in many isotope systems. the overwhelming majority of isotopic data for cais is limited to inclusions from the cv chondrite allende and a few other cv, co, cm, and ordinary chondrit... | titanium isotope signatures of calcium-aluminum-rich inclusions from cv and ck chondrites: implications for early solar system reservoirs and mixing |
we present keck/mosfire (multi-object spectrometer for infrared exploration) and keck/lris (low resolution imaging spectrometer) spectroscopy of a1689-217, a lensed (magnification ∼7.9), star-forming (sfr ∼ 16 m ⊙ yr-1), dwarf (log(m */m ⊙) = 8.07-8.59) lyα emitter (ew0 ∼ 138 å) at z = 2.5918. dwarf galaxies similar to... | the detection of [o iii] λ4363 in a lensed, dwarf galaxy at z = 2.59: testing metallicity indicators and scaling relations at high redshift and low mass |
ck vul erupted in 1670 and is considered a galactic stellar-merger candidate. its remnant, observed 350 yr after the eruption, contains a molecular component of surprisingly rich composition, including polyatomic molecules as complex as methylamine (ch3nh2). we present interferometric line surveys with subarcsec resolu... | molecular remnant of nova 1670 (ck vulpeculae). i. properties and enigmatic origin of the gas |
low-resolution lamost and keck spectra of blue supergiant stars distributed over the disks of the local group spiral galaxies m31 and m33 are analyzed to determine stellar effective temperatures, gravities, metallicities, and reddening. logarithmic metallicities at the center of the galaxies (in solar units) of 0.30 ± ... | a spectroscopic study of blue supergiant stars in local group spiral galaxies: andromeda and triangulum |
low-resolution spitzer-irs spectral map data of a reflection nebula (ngc 7023), h ii region (m17), and planetary nebula (ngc 40), totaling 1417 spectra, are analyzed using the data and tools available through the nasa ames pah ir spectroscopic database. the polycyclic aromatic hydrocarbon (pah) emission is broken down ... | the charge state of polycyclic aromatic hydrocarbons across a reflection nebula, an h ii region, and a planetary nebula |
earth's origins are challenging to elucidate, given the lack of surviving terrestrial geology from the first 500 myr of the solar system. in this review, we discuss breakthroughs in geochemistry and theoretical modelling that have advanced understanding of earth accretion. theory holds that solar nebula dust particles ... | the accretion of planet earth |
emission-line stars are typically surrounded by dense circumstellar material, often in form of rings or disc-like structures. line emission from forbidden transitions trace a diversity of density and temperature regimes. of particular interest are the forbidden lines of [o i] λλ6300, 6364 and [ca ii] λλ7291, 7324. they... | spectroscopic survey of emission-line stars - i. b[e] stars |
magnetic reconnection and non-thermal particle distributions associated with current-driven instabilities are investigated by means of resistive magnetohydrodynamics (mhd) simulations combined with relativistic test particle methods. we propose a system with two parallel, repelling current channels in an initially forc... | reconnection and particle acceleration in interacting flux ropes - i. magnetohydrodynamics and test particles in 2.5d |
we report confirmation of a large, evolved, bipolar planetary nebula and its blue, white dwarf central star as a member of the ~500 myr old galactic open star cluster m37 (ngc 2099). this is only the third known example of a planetary nebula in a galactic open cluster and was found via our ongoing program of identifyin... | the planetary nebula in the 500 myr old open cluster m37 |
we conjecture that observed protoplanetary disc accretion rates may be explained with low viscosities, which could be the result of hydrodynamic turbulence. we show that viscosities parametrized in the usual way with α ≳ 10-4, comparable to values suggested for hydrodynamic turbulence, can explain the observed accretio... | how do t tauri stars accrete? |
we described the design and operation principles of a new tunable-filter photometer developed for the 1-m telescope of the special astrophysical observatory of the russian academy of sciences and the 2.5-m telescope of the sternberg astronomical institute of the moscow state university. the instrument is mounted on the... | mapper of narrow galaxy lines (mangal): new tunable filter imager for caucasian telescopes |
we discuss the observational properties of pulsar wind nebulae (pwne) linking them to the injected (at the termination shock) electron spectral energy distribution and parameters of pulsar magnetospheres. in particular, we (1) present spatially-resolved chandra acis spectral maps of twelve pwne and measure the slopes o... | toward understanding the physical underpinnings of spatial and spectral morphologies of pulsar wind nebulae |
the projection factor (p-factor) is an essential component of the classical baade-wesselink (bw) technique, which is commonly used to determine the distances to pulsating stars. it is a multiplicative parameter used to convert radial velocities into pulsational velocities. as the bw distances are linearly proportional ... | observational calibration of the projection factor of cepheids. iii. the long-period galactic cepheid rs puppis |
we present a catalogue of 618 high-amplitude infrared variable stars (1 < δk < 5 mag) detected by the two widely separated epochs of 2.2 μm data in the ukidss galactic plane survey, from searches covering ∼1470 deg2. most were discovered by a search of all fields at 30 < l < 230°. sources include new dusty ... | extreme infrared variables from ukidss - ii. an end-of-survey catalogue of eruptive ysos and unusual stars |
we report on the results of deep and wide-field (1.1 deg2) narrow-band observations with subaru/hyper suprime-cam (hsc) of a field around a hyperluminous qso (hlqso), hs 1549+1919, residing in a protocluster at z = 2.84, to map the large-scale structure of lyα emitters (laes). one hsc pointing enables us to detect 3490... | lyα view around a z = 2.84 hyperluminous qso at a node of the cosmic web† |
we present analysis of the gas kinematics of the integral-shaped filament (isf) in orion a using four different molecular lines, 12co (1-0), 13co (1-0), nh3 (1,1), and n2h+ (1-0). we describe our method to visualize the position-velocity (pv) structure using the intensity-weighted line velocity centroid, which enables ... | gas velocity structure of the orion a integral-shaped filament |
context. many if not most planetary nebulae (pne) are now thought to be the outcome of binary evolutionary scenarios. however, only a few percent of the pne in the milky way are known to host binary systems. the high-precision repeated observing and long time baseline of gaia make it well suited for detecting new close... | towards a more complete sample of binary central stars of planetary nebulae with gaia |
we report results from a new hubble space telescope campaign that targets the o vi λ λ 1032,1038 å doublet in emission around intensely star-forming galaxies. the program aims to characterize the energy balance in starburst galaxies and gas cooling in the difficult-to-map coronal temperature regime of 2{--}5× {10}5 k. ... | o vi emission imaging of a galaxy with the hubble space telescope: a warm gas halo surrounding the intense starburst sdss j115630.63+500822.1 |
we present a deep centimeter-wavelength catalog of the orion nebula cluster (onc), based on a 30 hr single-pointing observation with the karl g. jansky very large array in its high-resolution a-configuration using two 1 ghz bands centered at 4.7 and 7.3 ghz. a total of 556 compact sources were detected in a map with a ... | the population of compact radio sources in the orion nebula cluster |
we report on simultaneous x-ray and radio observations of the radio-mode-switching pulsar psr b1822-09 with esa's xmm-newton and the westerbork synthesis radio telescope, giant metrewave radio telescope and lovell radio telescopes. psr b1822-09 switches between a radio-bright and radio-quiet mode, and we discovered a r... | simultaneous x-ray and radio observations of the radio-mode-switching pulsar psr b1822-09 |
during its early evolution, a pulsar wind nebula (pwn) sweeps the inner part of the supernova ejecta and forms a thin massive shell. later on, when the shell has been reached by the reverse shock of the supernova remnant, the evolution becomes more complex, in most cases reverting the expansion into a compression: this... | reverberation of pulsar wind nebulae - ii. anatomy of the 'thin-shell' evolution |
we present the data and analysis of sn 2018gjx, an unusual low-luminosity transient with three distinct spectroscopic phases. phase i shows a hot blue spectrum with signatures of ionized circumstellar material (csm), phase ii has the appearance of broad sn features, consistent with those seen in a type iib supernova at... | sn 2018gjx reveals that some sne ibn are sne iib exploding in dense circumstellar material |
context. accurate distance measurements are fundamental to the study of planetary nebulae (pne) but they have long been elusive. the most accurate and model-independent distance measurements for galactic pne come from the trigonometric parallaxes of their central stars, which were only available for a few tens of objec... | searching for central stars of planetary nebulae in gaia dr2 |
young massive stars regulate the physical conditions, ionization, and fate of their natal molecular cloud and surroundings. it is important to find tracers that quantify the stellar feedback processes that take place on different spatial scales. we present 85 arcmin2 velocity-resolved maps of several submillimeter mole... | molecular tracers of radiative feedback in orion (omc-1). widespread ch+ (j = 1-0), co (10-9), hcn (6-5), and hco+ (6-5) emission |
context. energy and momentum injected by young, massive stars into the surrounding gas play an important role in regulating further star formation and in determining the galaxy's global properties. before supernovae begin to explode, stellar feedback consists of two main processes: radiation pressure and photoionisatio... | stellar feedback in m 83 as observed with muse. ii. analysis of the h ii region population: ionisation budget and pre-sn feedback |
english and spanish translations are provided for fritz zwicky's seminal article on "the redshift of extragalactic nebulae", published in german in helvetica physica acta in 1933 <https://www.e-periodica.ch/digbib/view?pid=hpa-001:1933:6#112>. this paper is usually cited as the first evidence for dark matter ("du... | english and spanish translation of zwicky's (1933) the redshift of extragalactic nebulae |
we present the first far-uv (fuv) imaging results of the intermediate-age galactic open cluster ngc 2818 that has a planetary nebula (pn) within the field using images taken from the ultra violet imaging telescope (uvit) aboard astrosat. we identify cluster members by combining uvit-detected sources with gaia edr3 data... | uocs-ix. astrosat/uvit study of the open cluster ngc 2818: blue stragglers, yellow stragglers, planetary nebula, and their membership |
we present a detailed analysis of broadband x-ray observations of the pulsar psr j1420-6048 and its wind nebula (pwn) in the kookaburra region with chandra, xmm-newton, and nustar. using the archival xmm-newton and new nustar data, we detected 68 ms pulsations of the pulsar and characterized its x-ray pulse profile, wh... | x-ray studies of the pulsar psr j1420-6048 and its tev pulsar wind nebula in the kookaburra region |
magnetars have been considered as progenitors of magnetar giant flares (mgfs) and fast radio bursts (frbs). we present detailed studies on afterglow emissions caused by bursts that occur in their wind nebulae and surrounding baryonic ejecta. in particular, following the bursts-in-bubble model, we analytically and numer... | multiwavelength afterglow emission from bursts associated with magnetar flares and fast radio bursts |
fast, ejected stars have been found around several young star-forming regions, such as the orion nebula cluster. these ejected stars can be used to constrain the initial density, spatial and kinematic substructure when compared to predictions from n-body simulations. we search for runaway and slower walkaway stars usin... | constraining the initial conditions of ngc 2264 using ejected stars found in gaia dr2 |
we investigated the inventory of presolar silicate, oxide, and silicon carbide (sic) grains of fine-grained chondrule rims in six mighei-type (cm) carbonaceous chondrites (banten, jbilet winselwan, maribo, murchison, murray and yamato 791198), and the cm-related carbonaceous chondrite sutter's mill. sixteen o-anomalous... | the presolar grain inventory of fine-grained chondrule rims in the mighei-type (cm) chondrites |
the southern h ii region discovery survey (shrds) is a 900 hr australia telescope compact array 4-10 ghz radio continuum and radio recombination line (rrl) survey of galactic h ii regions and infrared-identified h ii region candidates in the southern sky. for this data release, we reprocess all previously published shr... | the southern h ii region discovery survey. ii. the full catalog |
meteorites are fascinating cosmic visitors. using accessible language, this book documents the history of mineralogy and meteorite research, summarizes the mineralogical characteristics of the myriad varieties of meteorites, and explains the mineralogical characteristics of solar system bodies visited by spacecraft. so... | meteorite mineraology |
the majority of gas giants (planets of masses ≳102 m ⊕) are found to reside at distances beyond ∼1 au from their host stars. within 1 au, the planetary population is dominated by super-earths of 2-20 m ⊕. we show that this dichotomy between inner super-earths and outer gas giants can be naturally explained should they ... | inner super-earths, outer gas giants: how pebble isolation and migration feedback keep jupiters cold |
context. most of the optically classified low-ionisation, narrow emission-line regions (liners) nuclei host an active galactic nucleus (agn). however, how they fit into the unified model (um) of agn is still an open question.aims: the aims of this work are to study at mid-infrared (mid-ir) (1) the compton-thick nature ... | nuclear obscuration in liners. clues from spitzer/irs spectra on the compton thickness and the existence of the dusty torus |
certain planetary nebulae (pne) contain shells, filaments, or globules of cold gas and dust whose heating and chemistry are likely driven by uv and x-ray emission from their central stars and from wind-collision-generated shocks. we present the results of a survey of molecular line emission in the 88-236 ghz range from... | a new radio molecular line survey of planetary nebulae. hnc/hcn as a diagnostic of ultraviolet irradiation |
this paper explores the influences and consequences of toroidal magnetic fields in shaping the visible lobes of pre-planetary nebulae (prepne). to probe these influences we start with the steady, diverging, and field-free wind model of our previous papers and add weak to moderate toroidal fields to the winds in order t... | models of the mass-ejection histories of pre-planetary nebulae. iv. magnetized winds and the origins of jets, bullets, and fliers |
the standard approach to the long-term evolution of pulsar wind nebulae (pwne) is based on one-zone models treating the nebula as a uniform system. in particular for the late phase of evolved systems, many of the generally used prescriptions are based on educated guesses for which a proper assessment lacks. using an ad... | reverberation of pulsar wind nebulae (i): impact of the medium properties and other parameters upon the extent of the compression |
we examine the images of hundreds of planetary nebulae (pne) and find that for about one in six pne the morphology is too “messy” to be accounted for by models of stellar binary interaction. we speculate that interacting triple stellar systems shaped these pne. in this preliminary study, we qualitatively classify pne b... | planetary nebulae that cannot be explained by binary systems |
the common assumption that {θ }1 {ori} {{c}} is the dominant ionizing source for the orion nebula is critically examined. this assumption underlies much of the existing analysis of the nebula. in this paper we establish through comparison of the relative strengths of emission lines with expectations from cloudy models ... | which stars are ionizing the orion nebula? |
we present two new radio continuum images from the australian square kilometre array pathfinder (askap) survey in the direction of the small magellanic cloud (smc). these images are part of the evolutionary map of the universe (emu) early science project (esp) survey of the small and large magellanic clouds. the two ne... | the askap emu early science project: radio continuum survey of the small magellanic cloud |
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