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we present results from the intermediate redshift osiris chemo-kinematic survey (irocks) for sixteen z ∼ 1 and one z ∼ 1.4 star-forming galaxies. all galaxies were observed with osiris with the laser guide star adaptive optics system at keck observatory. we use rest-frame nebular hα emission lines to trace morphologies... | irocks: spatially resolved kinematics of z ∼ 1 star-forming galaxies |
we investigate the dynamics of bow shock nebulae created by pulsars moving supersonically through a partially ionized interstellar medium. a fraction of interstellar neutral hydrogen atoms penetrating into the tail region of a pulsar wind will undergo photoionization due to the ultraviolet light emitted by the nebula, ... | mass loading of bow shock pulsar wind nebulae |
we report the first spectroscopic observations of a background star seen through the region between the ionization front and the dissociation front of the nebula ic 63. this photodissociation region (pdr) exhibits intense extended red emission (ere) attributed to fluorescence by large molecules/ions. we detected strong... | are the carriers of diffuse interstellar bands and extended red emission the same? |
jupiter's sodium nebula, which originates from io's volcanic gas, shows variations in its brightness due to the volcanic activity on io. imaging observation of d-line brightness in the sodium nebula was performed from 2013 through 2015 in a conjunction with the hisaki mission. the d-line brightness of the sodium nebula... | brightening event seen in observations of jupiter's extended sodium nebula |
free-floating (or rogue) planets are planets that are liberated (or ejected) from their host systems. although simulations predict their existence in substantial numbers, direct observational evidence for free-floating planets with masses below ~5 m jup is still lacking. several cycle-1 observing programs with jwst aim... | rogue planets and brown dwarfs: predicting the populations free-floating planetary mass objects observable with jwst |
the ic 5146 cloud is a nearby star-forming region in cygnus, consisting of molecular gas filaments in a variety of evolutionary stages. we used optical and near-infrared polarization data toward the ic 5146 cloud, reported in the first paper of this series, to reveal the magnetic fields in this cloud. using the newly r... | multiwavelength polarimetry of the filamentary cloud ic 5146. ii. magnetic field structures |
common features of all carbonaceous chondrite groups are invariant refractory element ratios, depletions of moderately volatile elements as a function of their condensation temperature (tc), and strongly depleted highly volatile element concentrations independent of tc. the depletion of volatile elements with respect t... | carbonaceous chondrites and the condensation of elements from the solar nebula |
cool gas (t~104 k) traced by hydrogen ly α emission is now routinely detected around z ~ 3 quasars, but little is known about their molecular gas reservoirs. here, we present an apex spectroscopic survey of the co(6-5), co(7-6), and [c i](2-1) emission lines for nine quasars from the qso museum survey, which have simil... | apex at the qso museum: molecular gas reservoirs associated with z 3 quasars and their link to the extended ly α emission |
secondary ionisation mass spectrometry (sims) u-th-pb dating of cassiterite with very low to sub-ppm u contents, zircon and monazite has provided direct measurements of the ages of mesoproterozoic-neoproterozoic pegmatite and quartz vein sn mineralisation in the karagwe-ankole belt (kab), rwanda, and through dates on l... | shrimp u-pb dating of cassiterite: insights into the timing of rwandan tin mineralisation and associated tectonic processes |
we model callisto's exosphere based on its ice as well as non-ice surface via the use of a monte-carlo exosphere model. for the ice component we implement two putative compositions that have been computed from two possible extreme formation scenarios of the satellite. one composition represents the oxidizing state and ... | monte-carlo simulation of callisto's exosphere |
accurate radial velocity determinations of optical emission lines (i.e., [nii] λλ 6548, 6584, hα and [s ii] λλ 6717, 6731) are very important for investigating the kinematic and dynamic properties of nebulae. the second stage survey program of large sky area multi-object fiber spectroscopic telescope (lamost) has start... | on the radial velocity calibrations in the lamost medium-resolution spectroscopic survey of nebulae |
we find that the remnant of supernova (sn) 1987a shares some morphological features with four supernova remnants (snrs) that have signatures of shaping by jets, and from that we strengthen the claim that jets played a crucial role in the explosion of sn 1987a. some of the morphological features appear also in planetary... | explaining the morphology of supernova remnant (snr) 1987a with the jittering jets explosion mechanism |
we report a computational study of the stability and infrared (ir) vibrational spectra of neutral and singly ionized fullerene cages containing between 44 and 70 carbon atoms. the stability is characterized in terms of the standard enthalpy of formation per cc bond, the homo-lumo gap, and the energy required to elimina... | searching for stable fullerenes in space with computational chemistry |
the lines of sight to highly reddened sne ia show peculiar continuum polarization curves, growing towards blue wavelengths and peaking at λmax ≲ 0.4 μ m like no other sightline to any normal galactic star. we examined continuum polarization measurements of a sample of asymptotic giant branch (agb) and post-agb stars fr... | common continuum polarization properties: a possible link between proto-planetary nebulae and type ia supernova progenitors |
we have performed combined photoionization and photodissociation region (pdr) modelling of a crab nebula filament subjected to the synchrotron radiation from the central pulsar wind nebula, and to a high flux of charged particles; a greatly enhanced cosmic-ray ionization rate over the standard interstellar value, ζ0, i... | modelling the arh+ emission from the crab nebula |
we have determined δ‧26mgdsm-3, the mass-independent variations in 26mg/24mg, of primitive, bulk meteorites to precisions better than ±3 ppm (2se). our measurements of samples from 10 different chondrite groups show δ‧26mgdsm-3 that vary from -5 to 22 ppm. our data define an array with a positive slope in a plot of δ‧2... | bulk chondrite variability in mass independent magnesium isotope compositions - implications for initial solar system 26al/27al and the timing of terrestrial accretion |
aims: the spatial structure of the emission lines and continuum over the 50″ extent of the nearby, o-rich, pn ngc 7009 (saturn nebula) have been observed with the muse integral field spectrograph on the eso very large telescope. this study concentrates on maps of line emission and their interpretation in terms of physi... | an imaging spectroscopic survey of the planetary nebula ngc 7009 with muse★ |
the very high energy gamma-ray emission reported from a number of pulsar wind nebulae (pwne) is naturally explained by the inverse compton scattering of multi-tev electrons. however, the physical dimensions of some gamma-ray-emitting pwne significantly exceed the scales anticipated by the standard hydrodynamical paradi... | on the anomalously large extension of the pulsar wind nebula hess j1825-137 |
radial abundance gradients are observed in the galaxy and other galaxies as well, and include several chemical elements in different stellar systems. possibly the most accurate gradients in the galaxy are those determined from chepheid variable stars. these objects have very accurate abundances for many elements and ar... | galactic radial abundance gradients: cepheids and photoionized nebulae |
based on imaging and spectroscopic data, we develop a 3d model for the huygens region of the orion nebula. θ^{1} ori c, the hottest star in the trapezium, is surrounded by a wind-blown central bubble that opens sw into the extended orion nebula. outside of this feature lies a layer of ionized gas at about 0.4 pc from θ... | deciphering the 3d orion nebula-i: expanding shells in the huygens region |
the wolf-rayet 98a (wr 98a) system is a prime target for interferometric surveys, since its identification as a `rotating pinwheel nebulae', where infrared images display a spiral dust lane revolving with a 1.4 yr periodicity. wr 98a hosts a wc9+ob star, and the presence of dust is puzzling given the extreme luminositi... | pinwheels in the sky, with dust: 3d modelling of the wolf-rayet 98a environment |
we estimate the accretion rates of 235 classical t tauri star (ctts) candidates in the lagoon nebula using ugri h α photometry from the vst photometric h α survey+. our sample consists of stars displaying h α excess, the intensity of which is used to derive accretion rates. for a subset of 87 stars, the intensity of th... | classical t tauri stars with vphas+ - i. h α and u-band accretion rates in the lagoon nebula m8 |
the argo-ybj air shower detector monitored the crab nebula gamma-ray emission from 2007 november to 2013 february. the integrated signal, consisting of ~3.3 × 105 events, reached the statistical significance of 21.1 standard deviations. the obtained energy spectrum in the energy range 0.3-20 tev can be described by a p... | crab nebula: five-year observation with argo-ybj |
planetary nebulae are ionized clouds of gas formed by the hydrogen-rich envelopes of low- and intermediate-mass stars ejected at late evolutionary stages. the strong uv flux from their central stars causes a highly stratified ionization structure, with species of higher ionization potential closer to the star. here, we... | the inside-out planetary nebula around a born-again star |
we present optical and near-infrared observations of the type iib supernova (sn) 2011fu from a few days to ∼300 d after explosion. the sn presents a double-peaked light curve (lc) similar to that of sn 1993j, although more luminous and with a longer cooling phase after the primary peak. the spectral evolution is also s... | sn 2011fu: a type iib supernova with a luminous double-peaked light curve |
we present a sample of resolved galactic h ii regions and photodissociation regions (pdrs) observed with the spitzer infrared spectrograph in spectral mapping mode between the wavelengths of 5-15 μm. for each object we have spectral maps at a spatial resolution of ∼4″ in which we have measured all of the mid-infrared e... | polycyclic aromatic hydrocarbon emission in spitzer/irs maps. i. catalog and simple diagnostics |
we discuss recent claims that the free electrons in ionized nebulae may not have a significantly maxwellian velocity distribution. supra-thermal electrons, electrons with much more energy than is encountered at electron temperatures found in nebulae, may solve the t^2/adf puzzle, the observations that abundances obtain... | the abundance discrepancy factor and t^2 in nebulae: are non-thermal electrons the culprits? |
in this contribution we review the recent progress in the modelling of pulsar wind nebulae (pwn). we start with a brief overview of the relevant physical processes in the magnetosphere, the wind-zone and the inflated nebula bubble. radiative signatures and particle transport processes obtained from 3d simulations of pw... | modelling jets, tori and flares in pulsar wind nebulae |
context. ag peg is known as the slowest symbiotic nova, which experienced its nova-like outburst around 1850. after 165 yr, during june of 2015, it erupted again showing characteristics of the z and-type outburst.aims: the primary objective is to determine basic characteristics, the nature and type of the 2015 outburst... | new outburst of the symbiotic nova ag pegasi after 165 yr |
low-luminosity active galactic nuclei (llagn) are special among their kind due to the profound structural changes that the central engine experiences at low accretion rates (≲ 10−3 in eddington units). the disappearance of the accretion disc - the blue bump - leaves behind a faint optical nuclear continuum whose nature... | compact jets dominate the continuum emission in low-luminosity active galactic nuclei |
we matched the astrometry of central stars (css) of spectroscopically confirmed galactic planetary nebulae (pne) with dr2 gaia parallaxes (p), finding 430 targets in common with p > 0 and $| {\sigma }_{{\rm{p}}}/p| \lt 1$ ∣ σ p / p ∣ < 1 . a catalog of pne whose css have dr2 gaia parallaxes is presented in table ... | the population of galactic planetary nebulae: a study of distance scales and central stars based on the second gaia release |
we report the results from a pilot search for radio recombination line (rrl) emission at millimeter wavelengths in a small sample of pre-planetary nebulae (ppne) and young pne (ypne) with emerging central ionized regions. observations of the h30α, h31α, h39α, h41α, h48β, h49β, h51β, and h55γ lines at 1 and 3 mm have be... | a pilot search for mm-wavelength recombination lines from emerging ionized winds in pre-planetary nebulae candidates |
magnetic energy around compact objects often dominates over plasma rest mass, and its dissipation can power the object's luminosity. we describe a dissipation mechanism that works faster than magnetic reconnection. the mechanism involves two strong alfvén waves with anti-aligned magnetic fields b1 and b2 that propagate... | fast dissipation of colliding alfvén waves in a magnetically dominated plasma |
we present a hyperspectral cube of the crab nebula obtained with the imaging fourier transform spectrometer sitelle on the canada-france-hawaii telescope. we describe our techniques used to deconvolve the 310 000 individual spectra ($r = 9\, 600$) containing hα, [n ii] λλ6548, 6583, and [s ii] λλ6716, 6731 emission lin... | 3d mapping of the crab nebula with sitelle - i. deconvolution and kinematic reconstruction |
wide-field h α images of the galactic plane have revealed a new supernova remnant (snr) nearly 3 deg in diameter centred at l = 107.0, b = +9.0. deep and higher resolution h α and [o iii] 5007 å images show dozens of h α filaments along the remnant's northern, western, and southwestern limbs, but few [o iii] bright fil... | g107.0+9.0: a new large optically bright, radio, and x-ray faint galactic supernova remnant in cepheus |
we investigate the effects of stellar populations and sizes on lyα escape in 27 spectroscopically confirmed and 35 photometric lyα emitters (laes) at z ≈ 2.65 in seven fields of the boötes region of the noao deep wide-field survey. we use deep hst/wfc3 imaging to supplement ground-based observations and infer key galax... | lyα escape from low-mass, compact, high-redshift galaxies |
new x-ray and optical observations shed light on the remarkable x-ray filament of the gamma-ray pulsar psr j2030+4415. images of the associated hα bow shock's evolution over the past decade compared with its velocity structure provide an improved kinematic distance of ~0.5 kpc. these velocities also imply that the puls... | the long filament of psr j2030+4415 |
we use medium-resolution keck/echellette spectrograph and imager spectroscopy of bright quasars to study cool gas traced by ca ii λλ3934, 3969 and na i λλ5891, 5897 absorption in the interstellar/circumgalactic media of 21 foreground star-forming galaxies at redshifts 0.03 < z < 0.20 with stellar masses 7.4 ≤ log... | on the kinematics of cold, metal-enriched galactic fountain flows in nearby star-forming galaxies |
the central star of the planetary nebula (pn) hubi 1 has been recently proposed to have experienced a very late thermal pulse (vltp), but the dilution of the emission of the recent ejecta by that of the surrounding h-rich old outer shell has so far hindered confirming its suspected h-poor nature. we present here an ana... | chemistry and physical properties of the born-again planetary nebula hubi 1 |
one of the great surprises of the late 1980s was the discovery that the [o iii] λ5007 planetary nebula luminosity function (pnlf) could be used as a precision extragalactic standard candle. despite the lack of any robust theory for the phenomenon, the technique passed a myriad of internal and external tests, and became... | the planetary nebula luminosity function in the era of precision cosmology |
we used archival very long baseline interferometry (vlbi) data of active galactic nuclei (agn) observed from 1.4 to 86 ghz to measure the angular size of vlbi radio cores in 8959 agns. we analysed their sky distributions, frequency dependencies, and created the most densely sampled and complete to date distribution map... | tracing milky way scattering by compact extragalactic radio sources |
directly characterising the first generations of stars in distant galaxies is a key quest of observational cosmology. we present a case study of id53 at z = 4.77, the uv-brightest (but l⋆) star-forming galaxy at z > 3 in the muse extremely deep field with a mass of ≈109 m⊙. in addition to very strong lyman-α (lyα) e... | deciphering stellar metallicities in the early universe: case study of a young galaxy at z = 4.77 in the muse extremely deep field |
recently, the large high altitude air shower observatory (lhaaso) reported the discovery of 12 ultrahigh-energy (uhe; ɛ ≥ 100 tev) gamma-ray sources located in the galactic plane. a few of these uhe gamma-ray emitting regions are in spatial coincidence with pulsar wind nebulae (pwne). we consider a sample of five sourc... | study of maximum electron energy of sub-pev pulsar wind nebulae by multiwavelength modelling |
rejuvenating galaxies are unusual galaxies that fully quench and then subsequently experience a "rejuvenation" event to become star-forming once more. rejuvenation rates vary substantially in models of galaxy formation: 10%-70% of massive galaxies are expected to experience rejuvenation by z = 0. measuring the rate of ... | a simple spectroscopic technique to identify rejuvenating galaxies |
we present the results from the hitomi soft gamma-ray detector (sgd) observation of the crab nebula. the main part of sgd is a compton camera, which in addition to being a spectrometer, is capable of measuring polarization of gamma-ray photons. the crab nebula is one of the brightest x-ray/gamma-ray sources on the sky,... | detection of polarized gamma-ray emission from the crab nebula with the hitomi soft gamma-ray detector |
we present the largest compilation to date of optical observations during and following fast radio bursts (frbs). the data set includes our dedicated simultaneous and follow-up observations, as well as serendipitous archival survey observations, for a sample of 15 well-localized frbs: eight repeating and seven one-off ... | limits on simultaneous and delayed optical emission from well-localized fast radio bursts |
this is the first in a series of papers that present sets of different results for 136 compact, known planetary nebulae within a 10 × 10 degree region of the galactic bulge. we use a large, previously unpublished sample of our own extensive eso 8-m vlt deep imaging and spectroscopic data. this is combined with archival... | morphologies and central stars of planetary nebulae in the galactic bulge from vlt, hst and pan-starrs imaging |
we characterize massive stars (m > 8 m ⊙) in the nearby (d ∼ 0.8 mpc) extremely metal-poor (z ∼ 5% z ⊙) galaxy leo a using hubble space telescope ultraviolet (uv), optical, and near-infrared (nir) imaging along with keck/low-resolution imaging spectrograph and mmt/binospec optical spectroscopy for 18 main-sequence o... | a panchromatic study of massive stars in the extremely metal-poor local group dwarf galaxy leo a |
evolved low- to intermediate-mass stars are known to shed their gaseous envelope into a large, dusty, molecule-rich circumstellar nebula which typically develops a high degree of structural complexity. most of the large-scale, spatially correlated structures in the nebula are thought to originate from the interaction o... | atomium: the astounding complexity of the near circumstellar environment of the m-type agb star r hydrae. i. morpho-kinematical interpretation of co and sio emission |
we discuss the origin of the neon isotopic signatures in chondrites and in the terrestrial mantle. there are two primary possible origins for neon in the earth's mantle. one origin is the dissolution of a dense primordial atmosphere with a solar composition of 20ne/22ne >13.4 into the mantle in a possible magma ocea... | the origin of the neon isotopes in chondrites and on earth |
in order to study the nature, origin, and impact of turbulent velocity fluctuations in the ionized gas of the orion nebula, we apply a variety of statistical techniques to observed velocity cubes. the cubes are derived from high resolving power (r ≈ 40 000) longslit spectroscopy of optical emission lines that span a ra... | turbulence in the ionized gas of the orion nebula |
the abundance of volatile elements in the silicate earth relative to primitive chondrites provides an important constraint on the thermochemical evolution of the planet. however, an overabundance of indium relative to elements with similar nebular condensation temperatures is a source of debate. here we use ab initio m... | earth's volatile depletion trend is consistent with a high-energy moon-forming impact |
legionella pneumophila is, by far, the species most frequently associated with legionnaires’ disease (ld). human infection occurs almost exclusively by aerosol inhalation which places the bacteria in juxtaposition with alveolar macrophages. ld risk management is based on controlling water quality by applying standardiz... | characterization of aerosols containing legionella generated upon nebulization |
in this work, i estimate the δ18 o and δ17 o values of primordial water in cm chondrites to be 55 ± 13 and 35 ± 9‰, respectively, based on whole-rock o and h data. also, i found that the o and/or h data of antarctic meteorites are biased, which is attributed to terrestrial weathering. this characteristic o isotopic rat... | oxygen isotopic ratios of primordial water in carbonaceous chondrites |
context. most planetary nebulae (pne) show beautiful, axisymmetric morphologies despite their progenitor stars being essentially spherical. close binarity is widely invoked to help eject an axisymmetric nebula, after a brief phase of engulfment of the secondary within the envelope of the asymptotic giant branch (agb) s... | the ionised and molecular mass of post-common-envelope planetary nebulae. the missing mass problem |
we examine the evolution of late-time, optical nebular features of type ia supernovae (sne ia) using a sample consisting of 160 spectra of 27 normal sne ia taken from the literature as well as unpublished spectra of sn 2008q and asassn-14lp. particular attention was given to nebular features between 4000 and 6000 å in ... | progressive redshifts in the late-time spectra of type ia supernovae |
we develop a framework for a new definition of the galactic midplane, allowing for tilt ({θ }tilt}; rotation about galactic azimuth 90°) and roll ({θ }roll}; rotation about galactic azimuth 0°) of the midplane with respect to the current definition. derivation of the tilt and roll angles also determines the solar heigh... | a galactic plane defined by the milky way h ii region distribution |
whether planetary nebulae (pne) are predominantly the product of binary stellar evolution as some population synthesis models (psm) suggest remains an open question. around 50 short-period binary central stars (p ∼ 1 d) are known, but with only four with measured orbital periods over 10 d, our knowledge is severely inc... | salt hrs discovery of a long-period double-degenerate binary in the planetary nebula ngc 1360 |
we present narrowband near-infrared images of a sample of 11 galactic planetary nebulae (pne) obtained in the h2 2.122 μm and brγ 2.166 μm emission lines and the k c 2.218 μm continuum. these images were collected with the wide-field infrared camera on the 3.6 m canada-france-hawaii telescope (cfht); their unprecedente... | extended structures of planetary nebulae detected in h2 emission |
we explore the well-observed type iip supernova 2013ej with peculiar luminosity evolution. it is found that the hydrodynamic model cannot reproduce in detail the bolometric luminosity at both the plateau and the radioactive tail. yet the ejecta mass of 23-26 m⊙ and the kinetic energy of (1.2-1.4) × 1051 erg are determi... | luminous type iip sn 2013ej with high-velocity 56ni ejecta |
wr 112 is a dust-forming carbon-rich wolf-rayet (wc) binary with a dusty circumstellar nebula that exhibits a complex asymmetric morphology, which traces the orbital motion and dust formation in the colliding winds of the central binary. unraveling the complicated circumstellar dust emission around wr 112 therefore pro... | resolving decades of periodic spirals from the wolf-rayet dust factory wr 112 |
we develop a physical framework for interpreting high-resolution images and kinematics of pre-planetary nebulae (“prepne”). we use hydrodynamical models to infer the historical properties of fast collimated nuclear flows (“jet”) that successfully form hollow, candle-shaped lobes over ≈103 yr, including the density, mom... | models of the mass-ejection histories of pre-planetary nebulae. iii. the shaping of lobes by post-agb winds |
we present the results of a binary population study in the orion nebula cluster (onc) using archival hubble space telescope (hst) data obtained with the advanced camera for surveys in johnson v filter (hst proposal 10246, pi m. robberto). young clusters and associations hold clues to the origin and properties of multip... | a search for intermediate-separation low-mass binaries in the orion nebula cluster |
the classification of gapped phases of non-interacting fermions hinges on the tenfold symmetries and on the spatial dimension. the notion of dimension leads to a well defined demarcation between bulk and edge. here we explore the nature of topological phases in systems where the distinction between bulk and edge is neb... | fractalized metals |
abell 14 is a poorly studied object despite being considered a born-again planetary nebula. we performed a detailed study of its 3d morphology and ionization structure using the shape and mocassin codes. we found that abell 14 is a highly evolved, bipolar nebula with a kinematical age of ∼19 400 yr for a distance of 4 ... | deciphering the bipolar planetary nebula abell 14 with 3d ionization and morphological studies |
aims: we wish to assess the role of kinematics and neutral hydrogen column density in the escape and distribution of lyα photons.methods: we selected a sample of 76 lyα emitting galaxies from the vimos ultra deep survey (vuds) at 2 ≤ z ≤ 4. we estimated the velocity of the neutral gas flowing out of the interstellar me... | the vimos ultra deep survey. the role of hi kinematics and hi column density on the escape of lyα photons in star-forming galaxies at 2 < z < 4 |
a wide variety of molecules have recently been detected in the horsehead nebula photodissociation region (pdr) suggesting that: (i) gas-phase and grain chemistries should both contribute to the formation of organic molecules; and (ii) far-ultraviolet (fuv) photodesorption may explain the release into the gas phase of g... | a new study of the chemical structure of the horsehead nebula: the influence of grain-surface chemistry |
we present the discovery of a giant ≳100 kpc lyα nebula detected in the core of the x-ray emitting cluster cl j1449+0856 at z = 1.99 through keck/lris narrow-band imaging. this detection extends the known relation between lyα nebulae and overdense regions of the universe to the dense core of a 5-7 × 1013 m ⊙ cluster. t... | a giant lyα nebula in the core of an x-ray cluster at z = 1.99: implications for early energy injection |
we report the discovery and timing measurements of psr j1208-6238, a young and highly magnetized gamma-ray pulsar, with a spin period of 440 ms. the pulsar was discovered in gamma-ray photon data from the fermi large area telescope (lat) during a blind-search survey of unidentified lat sources, running on the distribut... | the braking index of a radio-quiet gamma-ray pulsar |
context. in the very first steps of the formation of a new planetary system, dust agglomerates grow inside the protoplanetary disk that rotates around the newly formed star. in this disk, collisions between the dust particles, induced by interactions with the surrounding gas, lead to sticking. aggregates start growing ... | submillimetre-sized dust aggregate collision and growth properties. experimental study of a multi-particle system on a suborbital rocket |
the carina star-forming region is one of the largest in the galaxy, and its massive star population is still being unveiled. the large number of stars combined with high, and highly variable, interstellar extinction makes it inherently difficult to find ob stars in this type of young region. we present the results of a... | a catalog of new spectroscopically confirmed massive ob stars in carina |
we have identified a population of passive spiral galaxies from photometry and integral field spectroscopy. we selected z < 0.035 spiral galaxies that have wise colours consistent with little mid-infrared emission from warm dust. matched aperture photometry of 51 spiral galaxies in ultraviolet, optical and mid-infra... | a photometrically and spectroscopically confirmed population of passive spiral galaxies |
we present the results of an expanded, long-term radial velocity search (25 years) for evidence of binarity in a sample of seven bright proto-planetary nebulae (ppne). the goal is to investigate the widely held view that the bipolar or point-symmetric shapes of planetary nebulae (pne) and ppne are due to binary interac... | where are the binaries? results of a long-term search for radial velocity binaries in proto-planetary nebulae |
while ml generates much economic value, many of us have problematic relationships with social media and other ml-powered applications. one reason is that ml often optimizes for what we want in the moment, which is easy to quantify but at odds with what is known scientifically about human flourishing. thus, through its ... | machine love |
we examine the assembly process and the observability of a first galaxy (m_vir≈ 10^9{ m_⊙ } at z ≈ 8) with cosmological zoom-in, hydrodynamic simulations, including the radiative, mechanical, and chemical feedback exerted by the first generations of stars. to assess the detectability of such dwarf systems with the upco... | signature of the first galaxies in jwst deep field observations |
context. endogenous or exogenous, dry or wet, various scenarios have been depicted for the origin of water on the rocky bodies in our solar system. hydrated silicates found in meteorites and in interplanetary dust particles, together with observations of abundant water reservoirs in the habitable zone of protoplanetary... | water delivery in the inner solar nebula. monte carlo simulations of forsterite hydration |
we present a catalog of high-precision proper motions in the orion nebula cluster (onc), based on treasury program observations with the hubble space telescope's (hst) acs/wfc camera. our catalog contains 2454 objects in the magnitude range of 14.2 < mf775w < 24.7, thus probing the stellar masses of the onc from ... | hubble space telescope astrometry in the orion nebula cluster: census of low-mass runaways |
the formation of jupiter is modeled via core-nucleated accretion, and the planet's evolution is simulated up to the present epoch. throughout the phases when the planet acquires most of its heavy-element content, the calculation of solids' accretion accounts for interactions with an evolving disk of planetesimals. the ... | growth of jupiter: formation in disks of gas and solids and evolution to the present epoch |
in order to obtain a complete census of the stellar and substellar population, down to a few ${m}_{\mathrm{jup}}$ in the ∼1 myr old orion nebula cluster, we used the infrared channel of the wide field camera 3 of the hubble space telescope with the f139m and f130n filters. these bandpasses correspond to the 1.4 μm h2o ... | hst survey of the orion nebula cluster in the h2o 1.4 μm absorption band. i. a census of substellar and planetary-mass objects |
very high energy γ -rays are one of the most important messengers of the relativistic non-thermal universe. the major motivation of very high energy γ -ray astronomy is to find sources of high energy cosmic rays. several astrophysical sources are known to accelerate cosmic rays to very high energies under extreme condi... | galactic and extragalactic sources of very high energy gamma rays |
we report on broadband x-ray properties of the rabbit pulsar wind nebula (pwn) associated with the pulsar psr j1418-6058 using archival chandra and xmm-newton data, as well as a new nustar observation. nustar data above 10 kev allowed us to detect the 110 ms spin period of the pulsar, characterize its hard x-ray pulse ... | a broadband x-ray study of the rabbit pulsar wind nebula powered by psr j1418-6058 |
phosphorus is a minor element that controls the formation of several key planetary minerals. it is also an element critical to the development of life. a common assumption of phosphorus chemistry is that at low temperatures, phosphorus would have been a volatile component of ices or gases in the outer solar system. her... | phosphorus volatility in the early solar nebula |
context. in recent years, winds from massive stars have been considered promising sites for investigating relativistic particle acceleration. in particular, the resulting bow-shaped shocks from the interaction of the supersonic winds of runaway stars with interstellar matter have been intensively observed at many diffe... | and then they were two: detection of non-thermal radio emission from the bow shocks of two runaway stars |
the large high altitude air shower observatory (lhaaso) detected 12 gamma-ray sources above 100 tev, which are the possible origins of galactic cosmic-rays. we summarize the neutrino measurements by icecube and antares in the vicinity of lhaaso sources to constrain the contribution of hadronic gamma-rays in these sourc... | constraints on hadronic contributions to lhaaso sources with neutrino observations |
short rise times of fast blue optical transients (fbots) require very light ejected envelopes, $m_{\rm ej} \le 10^{-1} \, \mathrm{m}_\odot$, much smaller than of a typical supernova. the detection by chandra of x-ray emission in at2020mrf of lx ~ 1042 erg s-1 after 328 d implies total, overall dominant, x-ray energetic... | on the nature of fast blue optical transients |
many double white dwarf (wd) mergers likely do not lead to a prompt thermonuclear explosion. we investigate the prospects for observationally detecting the surviving remnants of such mergers, focusing on the case of mergers of double carbon-oxygen wds. for ~104 yr, the merger remnant is observationally similar to an ex... | observational signatures of carbon-oxygen white dwarf merger remnants |
we present the results from the hst wfc3 and acs data on an archetypal galaxy undergoing ram pressure stripping (rps), eso 137-001, in the nearby cluster abell 3627. eso 137-001 is known to host a prominent stripped tail detected in many bands from x-rays, h α to co. the hst data reveal significant features indicative ... | hst viewing of spectacular star-forming trails behind eso 137-001 |
jets (fast collimated outflows) are claimed to be the main shaping agent of the most asymmetric planetary nebulae (pns), as they impinge on the circumstellar material at late stages of the asymptotic giant branch phase. the first jet detected in a pn was that of ngc 2392, yet there is no available image because of its ... | tomography of the unique ongoing jet in the planetary nebula ngc 2392 |
u-pb ages and hf isotope compositions of zircons from the chencai complex in zhejiang province have been determined to provide constraints on mechanisms of migmatization and tectonic evolution related to the early palaeozoic orogeny in the cathaysia block, south china. zircons from leucosome samples of migmatites are c... | zircon u-pb ages and hf isotope compositions of the chencai migmatite, central zhejiang province, south china: constraints on the early palaeozoic orogeny |
the sun's astrophysical birth environment affected the formation and composition of the solar system. primitive meteorites display mass-independent oxygen isotope anomalies that were likely caused by ultraviolet (uv) photochemistry of co gas-phase molecules, either (i) in the outer solar nebula by light from the young ... | cosmic symplectite recorded irradiation by nearby massive stars in the solar system's parent molecular cloud |
we analyse particle acceleration in explosive reconnection events in magnetically dominated proton-electron plasmas. reconnection is driven by large-scale magnetic stresses in interacting current-carrying flux tubes. our model relies on development of current-driven instabilities on macroscopic scales. these tilt-kink ... | reconnection and particle acceleration in interacting flux ropes - ii. 3d effects on test particles in magnetically dominated plasmas |
we present emission-line templates for passively-evolving (`retired') galaxies, useful for investigation of the evolution of the interstellar medium in these galaxies, and characterization of their high-temperature source populations. the templates are based on high signal-to-noise (>800) co-added spectra (3700-6800... | diffuse gas in retired galaxies: nebular emission templates and constraints on the sources of ionization |
we present observations of the trumpler 14/carina i region carried out using the stratospheric terahertz observatory 2. the trumpler 14/carina i region is in the western part of the carina nebula complex (cnc), which is one of the most extreme star-forming regions in the milky way. we observed trumpler 14/carina i in t... | probing ism structure in trumpler 14 and carina i using the stratospheric terahertz observatory 2 |
the well-known quasar sdss j095253.83+011421.9 (j0952+0114) at z = 3.02 has one of the most peculiar spectra discovered so far, showing the presence of narrow lyα and broad metal emission lines. although recent studies have suggested that a proximate damped lyα absorption (pdla) system causes this peculiar spectrum, th... | a giant lyα nebula and a small-scale clumpy outflow in the system of the exotic quasar j0952+0114 unveiled by muse |
high- and low-resolution international ultraviolet explorer (iue) spectra of v838 her in the early outburst stages exhibit a strong absorption feature shortward of λ3130. we discuss the nature of this spectral feature and provide convincing evidence that it corresponds to the blueshifted resonance doublet of singly ion... | absorption and emission features of 7be ii in the outburst spectra of v838 her (nova her 1991) |
projected quasar galaxy pairs provide powerful means to study the circumgalactic medium (cgm) that maintains the relics of galactic feedback and the accreted gas from the intergalactic medium. here, we study the nature of a lyman limit system (lls) with n(h i) = 1019.1 ± 0.3 cm-2 and a dust-uncorrected metallicity of [... | a lyman limit system associated with galactic winds |
the crab nebula is an extreme particle accelerator that boosts the energy of electrons up to a few pev (10^{15} ev), close to the maximum energy allowed theoretically. the physical conditions in the acceleration site and the nature of the acceleration process itself remain highly uncertain. the key information about th... | detection of ultra-high-energy gamma rays from the crab nebula: physical implications |
respiratory infection by pathogens via aerosol remains a major concern for both natural disease transmission as well as intentional release of biological weapons. critical to understanding the disease course and pathogenesis of inhaled pathogens are studies in animal models conducted under tightly controlled experiment... | a vibrating mesh nebulizer as an alternative to the collison three-jet nebulizer for infectious disease aerobiology |
we present atacama large millimeter/sub-millimeter array (alma) observations of the star-forming environment surrounding v1647 ori, an outbursting fuor/exor pre-main sequence star. dust continuum and the (j = 2 - 1) 12co, 13co, c18o molecular emission lines were observed to characterize the v1647 ori circumstellar disc... | the alma early science view of fuor/exor objects - iv. misaligned outflows in the complex star-forming environment of v1647 ori and mcneil's nebula |
we analyze far-ultraviolet spectra and ancillary data of the super star cluster ssc-n and its surrounding h ii region in the nearby dwarf galaxy ii zw 40. from the ultraviolet spectrum, we derive a low internal reddening of e(b - v) = 0.07 ± 0.03, a mass of (9.1 ± 1.0) × 105 m ⊙, a bolometric luminosity of (1.1 ± 0.1) ... | physical properties of ii zw 40's super star cluster and nebula: new insights and puzzles from uv spectroscopy |
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