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context. life is distinctly homochiral. the origins of this homochirality are under active debate. recently, propylene oxide has been detected in the gas-phase interstellar medium (ism). the enantiomeric composition of ism propylene oxide may be probed through circular polarization measurements, but accurate estimates ... | detecting chiral asymmetry in the interstellar medium using propylene oxide |
we used high-resolution [c ii] 158 μm mapping of two nebulae ic 59 and ic 63 from sofia/upgreat in conjunction with ancillary data of the gas, dust, and polarization to probe the kinematics, structure, and magnetic properties of their photodissociation regions (pdrs). the nebulae are part of the sh 2-185 h ii region th... | physics and chemistry of radiation driven cloud evolution. [c ii] kinematics of ic 59, and ic 63 |
the next generation balloon-borne large aperture submillimeter telescope (blast-tng) is a submillimeter polarimeter designed to map interstellar dust and galactic foregrounds at 250, 350, and 500 microns during a 24-day antarctic flight. the blast-tng detector arrays are comprised of 918, 469, and 272 mkid pixels, resp... | characterization, deployment, and in-flight performance of the blast-tng cryogenic receiver |
sulphur bearing nitrogenous compounds have been observed in space over this last decade. modelling their abundances has been done using rate coefficients of isoelectronic molecules. in order to satisfy the astrophysical precision required, we report the actual rate coefficients of ns+ induced by collision with the most... | hyperfine excitation of ns+ due to para-h2(j = 0) impact |
modern radio spectrometers make measurement of polarized intensity as a function of faraday depth possible. i investigate the effect of depolarization along a model line of sight. i model sightlines with two components informed by observations: a warm ionized medium with a lognormal electron density distribution and a ... | is there a polarization horizon? |
we present the first ab initio potential energy surfaces (pess) for the po(x2π)-he van der waals system. the pess were obtained using the open-shell partially spin-restricted coupled cluster approach with single, double and perturbative triple excitations [uccsd(t)]. the augmented correlation-consistent polarized valen... | collisional excitation of interstellar po(x2π) by he: new ab initio potential energy surfaces and scattering calculations |
context. be/x-ray binaries represent the main group of high-mass x-ray binaries. the determination of the astrophysical parameters of the counterparts of these high-energy sources is important for the study of x-ray binary populations in our galaxy. x-ray observations suggest that sax j2239.3+6116 is a be/x-ray binary.... | the optical counterpart to the be/x-ray binary sax j2239.3+6116 |
tracing magnetic field is crucial as magnetic field plays an important role in many astrophysical processes. earlier studies have demonstrated that ground state alignment (gsa) is an effective way to detect a weak magnetic field (1g≳ b≳ {{10}-15} g) in a diffuse medium. we explore the atomic alignment in the presence o... | tracing magnetic fields by atomic alignment in extended radiation fields |
polarization of interstellar dust emission is a powerful probe of dust properties and magnetic field structure. yet studies of external galaxies are hampered by foreground dust contribution. the study aims at separating the polarized signal from the large magellanic cloud (lmc) from that of the milky way (mw) to constr... | unveiling polarized emission from interstellar dust of the large magellanic cloud with planck |
we discuss gamma-ray signatures associated with an asymmetric explosion and transport of positrons in sn ia ejecta. in particular, compton scattering of gamma-ray line photons can induce polarization in the continuum, which would be a direct probe of the asymmetries in the distribution of radioactive isotopes and/or of... | polarization of mev gamma-rays and 511 kev line shape as probesof snia asymmetry and magnetic field |
aims: ngc 1502 is located at the periphery of the cam ob1 association and probably within the orion spur, with published distance estimates varying between 0.7 and 1.5 kpc. we combine new polarimetric observations and existing uvbyβ and ubv photometries to provide new estimates of the cluster's parameters.methods: we p... | interstellar polarization and extinction towards the young open cluster ngc 1502 |
we present the optical linear polarization observation of stars toward the core of the czernik 3 cluster in the sloan i band. the data were obtained using the empol instrument on the 1.2 m telescope at mount abu observatory. we study the dust distribution toward this cluster by combining the results from our polarizati... | optical linear polarization study toward czernik 3 open cluster at different spatial scales |
we present ubvri polarization observations of 12 b-type stars in the direction of the young open cluster ngc 6530, nine of them confirmed as probable members. the maximum degree of polarization for our target stars ranges from 0.16% to 2.84%, with an average value of 1.1%. we note variations of the polarization vector ... | interstellar extinction in the direction of the young open cluster ngc 6530 |
context. computing polarised intensities from noisy data in stokes u and q suffers from a positive bias that should be suppressed.aims: we aim to develop a correction method that, when applied to maps, should provide a distribution of polarised intensity that closely follows the signal from the source.methods: we propo... | a new method to suppress the bias in polarised intensity |
the polarized instrument for long-wavelength observation of the tenuous interstellar medium (pilot) is a balloon-borne experiment aiming at measuring the polarized emission of thermal dust at a wavelength of 240 mm (1.2 thz). a first pilot flight (flight#1) of the experiment took place from timmins, ontario, canada, in... | pilot balloon-borne experiment in-flight performance |
interstellar polarization in the optical/infrared has long been known to be due to asymmetrical dust grains aligned with the magnetic field and can potentially provide a resource effective way to probe both the topology and strength of the magnetic-field. however, to do so with confidence, the physics and variability o... | interstellar grain alignment: observational status |
discoverable interstellar communication signals are expected to exhibit al least one signal characteristic clearly distinct from random noise. a hypothesis is proposed that radio telescope received signals may contain transmitted delta-t delta-f opposite circular polarized pulse pairs, conveying a combination of inform... | symbol repetition in interstellar communications: methods and observations |
ngc 457 is a moderately reddened and relatively young open cluster very rich in variable stars, particularly be stars, but not associated with any prominent star-forming field. we combine new multi-wavelength polarization measurements with existing ubv and uvby photometries to obtain precise estimates of the total-to-s... | interstellar polarization and extinction towards the open cluster ngc 457 |
linear polarization has been observed in both the prompt phase and afterglow of some bright gamma-ray bursts (grbs). polarization in the prompt phase spans a wide range, and may be as high as ≳ 50%. in the afterglow phase, however, it is usually below 10%. according to the standard fireball model, grbs are produced by ... | polarization of gamma-ray burst afterglows in the synchrotron self-compton process from a highly relativistic jet |
we study the polarized radio emission from young type ia supernova remnants by means of three-dimensional numerical mhd simulations and the assumption of relativistic electron distribution related to magnetic field energy density. in our simulations, the turbulent component of background plasma is taken into account by... | 3d mhd numerical simulations of polarized emission in the turbulent background from young type ia supernova remnants |
polarized thermal emission from interstellar dust grains can be used to map magnetic fields in star forming molecular clouds and the diffuse interstellar medium (ism). the balloon-borne large aperture submillimeter telescope for polarimetry (blastpol) flew from antarctica in 2010 and 2012 and produced degree-scale pola... | instrumental performance and results from testing of the blast-tng receiver, submillimeter optics, and mkid detector arrays |
aims: the fact that the o-type close binary star system ao cassiopeiae exhibits variable phase-locked linear polarization has been known since the mid-1970s. in this work, we re-observe the polarization arising from this system more than 50 yr later to better estimate the interstellar polarization and to independently ... | high-precision broadband linear polarimetry of early-type binaries. iii. ao cassiopeiae revisited |
observational studies of magnetic fields are crucial. we introduce a process "ground state alignment" as a new way to determine the magnetic field direction in diffuse medium. the alignment is due to anisotropic radiation impinging on the atom/ion. the consequence of the process is the polarization of spectral lines re... | magnetic field measurement with ground state alignment |
the magneto-optical polarization rotation effect has myriad applications in many research areas spanning the scientific spectrum, including space and interstellar research, nanotechnology, material science, biomedical imaging, and subatomic particle research. in the nonlinear magneto-optical rotation (nmor) effect, the... | breaking the energy-symmetry-based propagation growth blockade in magneto-optical rotation |
based on the results from uv-irradiated interstellar ice analogues, we describe a two-step phenomenological theory for enantiomer-selective, asymmetric formation of molecules like amino acid precursors: (1) uv photolysis of interstellar ices to molecular fragments/radicals and formation of racemic population of chiral ... | enantiomeric excess of amino acids in interstellar ice analogues-asymmetric photolysis of precursors by circularly polarized uv light |
the fate of organometallic dust subjected to extreme conditions, especially the shock fronts, in the interstellar medium (ism) has not been explored to date. iron and cyclopentadiene, which have been found to be present in the ism, are known to react and produce the organometallic compound ferrocene under terrestrial c... | shock-induced transformation of non-magnetic to magnetic ism dust analogue |
a new method for measuring the global magnetic field structure of the galactic plane is presented. we have determined the near-infrared polarization of field stars around 52 cepheids found in recent surveys toward the galactic plane. the cepheids are located at the galactic longitudes $-10^{\circ} \le l \le +10.^{\!\!\... | magnetic field structure of the galactic plane from differential analysis of interstellar polarization |
according to the theory of dilatons, one of the main sources of dilatonic radiation is the first invariant of the electromagnetic field tensor. since for a plane electromagnetic wave this invariant equals to zero, wave propagation does not cause dilaton radiation. the first invariant of the electromagnetic field tensor... | dilaton generation while a plane electromagnetic wave propagates in coulomb field |
the structure of carbodiimide has been studied by using quantum chemical methods. carbodiimide (hncnh) has been detected towards sagittarius b2 (n) in interstellar medium (ism). two reaction mechanisms have been proposed to study the formation of interstellar carbodiimide. the first reaction mechanism is based on molec... | theoretical study of possible reaction mechanisms for the formation of carbodiimide in the interstellar medium (ism) and polarizabilities of carbodiimide |
we present polarimetric observations of stars in the field of the open cluster ngc 7160. the multi-wavelength ubvri polarization measurements of 21 stars that we performed indicate that some of the observed stars follow the typical wavelength dependence indicative of polarization by selective extinction in the interste... | interstellar extinction and polarization of stars in the open cluster ngc 7160 |
starlight polarization serves one of the powerful tools to study magnetic fields in the galactic interstellar medium. heiles catalogue contains polarization information for 9286 stars, and is by far the biggest. this catalogue has been extensively used to study the magnetic fields. however, the distance parameters of t... | a revisit to the optical starlight polarization catalogue by heiles: distance update |
aluminium hydroxide (aloh) is ubiquitous in the interstellar medium. however, there are no reliable data available in the literature that can be used to interpret the observations. therefore, in this paper, we deal with the rotational rate coefficients of aloh induced by collision with helium. the potential energy surf... | cross-sections and rate coefficients for rotational excitation of aluminium hydroxide by helium |
context. the planck catalogue of galactic cold clumps (pgcc) contains over 13 000 sources that are detected based on their cold dust signature. they are believed to consist of a mixture of quiescent, pre-stellar, and already star-forming objects within molecular clouds.aims: we extracted pgcc-type objects from cloud si... | synthetic observations of dust emission and polarisation of galactic cold clumps |
we present a near-infrared band-merged photometric and polarimetric catalog for the 39‧ × 69‧ fields in the northeastern part of the large magellanic cloud (lmc), which were observed using sirpol, an imaging polarimeter of the infrared survey facility. this catalog lists 1858 sources brighter than 14 mag in the h band ... | near-infrared polarization source catalog of the northeastern regions of the large magellanic cloud |
the local interstellar magnetic field affects both the heliosphere and the surrounding cluster of interstellar clouds (clic). measurements of linearly polarized starlight provide the only test of the magnetic field threading the clic. polarization measurements of the clic magnetic field show multiple local magnetic str... | connecting the interstellar magnetic field at the heliosphere to the loop i superbubble |
three-dimensional structure of the aquila rift of magnetized neutral gas is investigated by analysing h i and co line data. the projected distance on the galactic plane of the h i arch of the aquila rift is r⊥ ∼ 250 pc from the sun. the h i arch emerges at l ∼ 30°, reaches to altitudes as high as ∼500 pc above the plan... | three-dimensional aquila rift: magnetized h i arch anchored by molecular complex |
we present the measurement of the size and surface brightness of the expanding light echoes from supernova (sn) 2014j in the nearby starburst galaxy m82. hubble space telescope (hst) acs/wfc images were taken ~277 and ~416 days (after the time of b-band maximum light) in the filters f475w, f606w, and f775w, each combin... | the expanding light echoes from supernova 2014j in m82 |
we study the observable properties of compressible magnetohydrodynamic (mhd) turbulence covering different turbulence regimes, based on synthetic synchrotron observations arising from 3d mhd numerical simulations. using the synchrotron emissivity and intensity, we first explore how the cosmic-ray spectral indices affec... | studying the properties of compressible magnetohydrodynamic turbulence using synchrotron fluctuation statistics |
we present the results of ubvri polarimetry of the tev γ-ray binary hess j0632+057 obtained on 2015 march 24 (jd 245 7106) and 2015 december 12 (jd 245 7369). the detected polarization values of hess j0632+057, just after periastron passage (march 24), are higher than all previously published values (pv ∼ 4.2 per cent)... | first multicolour polarimetry of tev γ-ray binary hess j0632+057 close to periastron passage |
polarized emission from polycyclic aromatic hydrocarbons (pahs) potentially provides a new way to test the basic physics of the alignment of ultrasmall grains. in this paper, we present a new model of polarized pah emission that takes into account the effect of pah alignment with the magnetic field. we first generate a... | effect of alignment on polarized infrared emission from polycyclic aromatic hydrocarbons |
a photon can encode several bits of information based on an alphabet of its time of arrival, energy, and polarization. heisenberg's uncertainty principle places a limit on measuring pairs of physical properties of a particle, limiting the maximal information efficiency to <59 bits per photon in practice, and <171... | interstellar communication. viii. hard limits on the number of bits per photon |
we report on over 13 yr of optical and near-ultraviolet spectropolarimetric observations of the famous luminous blue variable (lbv) p cygni. in the lives of the most massive stars, lbvs are a critical transitional phase and achieve the largest mass-loss rates of any group of stars. using spectropolarimetry, we are able... | 13 yr of p cygni spectropolarimetry: investigating mass loss through hα, periodicity, and ellipticity |
we have investigated the magneto-ionic turbulence in the interstellar medium through spatial gradients of the complex radio polarization vector in the canadian galactic plane survey (cgps). the cgps data cover 1300 square degrees, over the range 53^\circ ≤slant {\ell }≤slant 192^\circ , -3^\circ ≤slant b≤slant 5^\circ ... | polarization gradient study of interstellar medium turbulence using the canadian galactic plane survey |
using the first station of the long wavelength array (lwa1), we examine polarized pulsar emission between 25 and 88 mhz. polarized light from pulsars undergoes faraday rotation as it passes through the magnetized interstellar medium. observations from low-frequency telescopes are ideal for obtaining precise rotation me... | detecting pulsar polarization below 100 mhz with the long wavelength array |
the canonical theory of star formation in a magnetized environment predicts the formation of hourglass-shaped magnetic fields during the prestellar collapse phase. in protostellar cores, recent observations reveal complex and strongly distorted magnetic fields in the inner regions that are sculpted by rotation and outf... | synthetic polarization maps of an outflow zone from magnetohydrodynamic simulations |
a method for measuring the difference between centroids of polarized flux and total flux of an astronomical object - polaroastrometry - is proposed. the deviation of the centroid of flux corresponding to stokes parameter q or u from the centroid of total flux multiplied by dimensionless stokes parameter q or u, respect... | on-sky demonstration of optical polaroastrometry |
the next-generation balloon-borne large-aperture submillimeter telescope (blast-tng) is a submillimeter imaging polarimeter which will map the polarized thermal emission from interstellar dust, revealing magnetic field structures in nearby giant molecular clouds, external galaxies and the diffuse interstellar medium in... | preflight detector characterization of blast-tng |
we report spectropolarimetric observations of the recurrent nova rs oph obtained during four nights between 2017 july and 2018 july. in the wavelength range from 5000 å to 8000 å, we find the maximum degree of linear polarization pl(obs)=2.9%±0.09 at λ≈5600 å and the position angle θ=47o.2±0o.9. we do not detect any va... | spectropolarimetric observations of the recurrent nova rs oph |
we present (bvri) multicolor linear polarimetric data of 73 of the brightest stars in the open cluster ngc 5662. our objective is to study the characteristics of the interstellar medium (ism) towards it and in its the environment. ngc 5662 is polarimetrically characterized by pv=2.27±0.13 and θv=89°.6±1.17. its polariz... | optical polarization study in the centaurus region: ngc 56621 |
we present the results of our ubvri polarimetric observations of a dozen stars located close to the well-studied bok globule barnard 5 (b5), with several of the stars being seen through its outer layers (with av up to ∼3 mag). using recent astrometric, spectroscopic and photometric surveys, we estimate the distance, sp... | dust in the outer layers of the barnard 5 globule |
context. the h2s molecule has been detected in several regions of the interstellar medium (ism). the use of non-lte models requires knowledge of accurate collisional rate coefficients of the molecules detected with the most common collider in the ism.aims: the main goal of this work is to study the collision of h2s wit... | rotational relaxation of h2s by collision with he |
the characteristics of radiative gravitational modes in non-thermal magnetized dusty plasma with charge fluctuation and the polarization force of dust particles are investigated. the electron species are assumed to be radiative and the ions are assumed to be non-thermal. a normal mode analysis is applied to derive the ... | analysis of radiative gravitational modes in magnetized dusty plasma with non-thermal ion distribution |
the polarized instrument for long-wavelength observation of the tenuous interstellar medium (pilot) is a balloon-borne experiment that aims to measure the polarized emission of thermal dust at a wavelength of 240 µm (1.2 thz). a first pilot flight of the experiment took place from timmins, ontario, canada, in september... | inflight performance of the pilot balloon-borne experiment |
the next generation balloon-borne large aperture submillimeter telescope (blast-tng) is a submillimeter mapping experiment planned for a 28 day long-duration balloon (ldb) flight from mcmurdo station, antarctica during the 2018-2019 season. blast-tng will detect submillimeter polarized interstellar dust emission, traci... | design and characterization of a balloon-borne diffraction-limited submillimeter telescope platform for blast-tng |
we report the detection of a circular polarization signature in the stokes v profile of a 25 ghz class i ch3oh maser toward the high-mass star-forming region omc-1. such a feature usually constitutes a detection of the zeeman effect. if due to a magnetic field in omc-1, this would represent the first detection and disc... | a curious case of circular polarization in the 25 ghz methanol maser line toward omc-1 |
polarimetry provides an avenue for probing the geometry and physical mechanisms producing optical radiation in many astrophysical objects, including stellar binary systems. we present the results of multiwavelength (bvr) polarimetric studies of a sample of historical black hole x-ray binaries, observed during their out... | optical polarization signatures of black hole x-ray binaries |
the polarized instrument for long-wavelength observation of the tenuous interstellar medium ( pilot) is a balloon-borne astronomy experiment designed to study the linear polarization of thermal dust emission in two photometric bands centred at wavelengths 240 μm (1.2 thz) and 550 μm (545 ghz), with an angular resolutio... | the optical performance of the pilot instrument from ground end-to-end tests |
we investigate the magnetic field in an intermediate-velocity filament for which the hα intensity in the wham survey correlates with excess faraday rotation of extragalactic radio sources over the length of the filament from b ≈ 20° to b ≈ 55°. the density-weighted mean magnetic field is 2.8 +/- 0.8 μ {{g}}, derived fr... | magnetic field strength in an intermediate-velocity ionized filament in the first galactic quadrant |
this paper outlines the life and scientific legacy of professor nikolai vasil'evich voshchinnikov (1951-2017) who had many coauthors and friends among the jqsrt community. | nikolai voshchinnikov: from light scattering by spheroids to large interstellar polarisation survey |
in this report accurate microwave (mw) stark effect measurements have been performed to obtain precise dipole moment and precise zero-field microwave frequencies of singly deuterated quasi symmetric ch3od methanol species. this species is of significance to radio astronomers to study the hydrogen-deuterium exchange in ... | far infrared laser, millimeter-wave and microwave microwave stark, millimeter wave, far infrared, infrared and far infrared laser spectroscopy of methanol-od (ch3 od): precise dipole moment and millimeter-wave atlas of astrophysical significance |
gravitational waves (gws, from binary merger) interacting with super-strong magnetic fields of the neutron star (in the same binary system), would lead to perturbed electromagnetic waves [emws, in the same frequencies of these gws, partially in the ultra-low-frequency (ulf) band for the emws]. such perturbed ulf-emws a... | ultra-low-frequency electromagnetic waves as signals and special counterparts of gravitational waves (from binary mergers) having tensorial and possible nontensorial polarizations |
we examine the evolution and emission of the supernova remnant (snr) ctb 109 using 3d magnetohydrodynamics simulations. the snr evolves in a medium divided by a plane interface into two media with different densities and pressure equilibrium. our results reveal that a remnant with the characteristics of ctb 109 is form... | 3d mhd simulations of the supernova remnant ctb 109 |
the composition of the relativistic plasma produced in active galactic nuclei and ejected via powerful jets into the interstellar/intergalactic medium is still a major unsettled issue. it might be a positron-electron plasma in case the plasma was created by pair production in the intense photon fields near accreting su... | determining the composition of radio plasma via circular polarization: the prospects of the cygnus a hot spots |
starlight polarization serves one of the powerful tools to study magnetic fields in the galactic interstellar medium. heiles catalogue contains polarization information for 9286 stars and is by far the biggest. this catalogue has been extensively used to study magnetic fields. however, the distance parameters of the st... | a revisit to the optical starlight polarization catalogue by heiles: distance update |
for more than 5000 stars with accurate parallaxes from the hipparcos and gaia dr1 tycho-gaia astrometric solution (tgas), tycho-2 photometry, interstellar polarization from eight catalogues and interstellar extinction from eight 3d maps the largest up to date comparison of the polarization and extinction is provided. t... | spatial variations of the interstellar polarization and interstellar extinction |
polarimetry of starlight observed through dust and observations of polarized thermal emission from this dust are some of the few ways to observe the presence of magnetic fields in the interstellar medium. not only is the strength and overall geometry of the magnetic field important in physical processes in the ism, the... | interstellar polarization and magnetic turbulence |
gigaparsec scale alignments of the quasar optical polarization vectors have been proven to be robust against a scenario of contamination by the galactic interstellar medium (ism). this claim has been established by means of optical polarization measurements of the starlight surrounding the lines of sight of the 355 qua... | cosmological-scale coherent orientations of quasar optical polarization vectors in the $planck$ era investigating the galactic dust contamination scenario |
the self-gravitational jeans instability has been studied in dusty plasma containing significant background of neutral pressure and recombination of ions and electrons on the dust surface. the full dynamics of charged dust grains, ions and neutral species are employed considering the electrons as maxwellian. we have de... | jeans instability of inhomogeneous dusty plasma with polarization force, ionization and recombination |
we present the results of near-infrared (nir) linear imaging polarimetry in the j, h, and ksbands of the low-mass star cluster-forming region in the circinus molecular cloud complex. using aperture polarimetry of point-like sources, positive detection of 314, 421, and 164 sources in the j, h, and ksbands, respectively,... | first near-infrared imaging polarimetry of young stellar objects in the circinus molecular cloud |
starlight linearly polarized by aligned interstellar dust grains provides the necessary data for tracing the structure of the very local interstellar magnetic field (ismf). two methods have been developed to recover the ismf direction from polarized starlight, using data from an ongoing polarization survey. both method... | following the interstellar magnetic field from the heliosphere into space with polarized starlight |
we present h-band (1.6 μm) scattered light observations of the transitional disk rx j1615.3-3255, located in the 1 myr old lupus association. from a polarized intensity image, taken with the hiciao instrument of the subaru telescope, we deduce the position angle and the inclination angle of the disk. the disk is found ... | radial decoupling of small and large dust grains in the transitional disk rx j1615.3-3255 |
we analyse 45 spectropolarimetric observations of the eclipsing, interacting binary star v356 sgr, obtained over a period of ∼21 yr, to characterize the geometry of the system's circumstellar material. after removing interstellar polarization from these data, we find that the system exhibits a large intrinsic polarizat... | the complex circumstellar and circumbinary environment of v356 sgr |
much of the information about the magnetic field in the milky way and other galaxies comes from measurements which are path integrals, such as faraday rotation and the polarization of synchrotron radiation of cosmic ray electrons. the measurement made at the radio telescope results from contributions of volume elements... | a method for a pseudo-local measurement of the galactic magnetic field |
massive young stars dynamically modify their surroundings, altering their stellar nurseries and the gas that exists between stars. with my research, i assess the modification of the galactic magnetic field within hii regions and stellar bubbles associated with ob stars. because hii regions are plasmas, magnetic fields ... | a study of magnetic fields in h ii regions using faraday rotation |
polarization is an under-exploited technique in the investigation of exoplanet atmospheres. a polarization detection, particularly if extended over a broad spectral range, will set valuable constraints on the gas and clouds in an exoplanet atmosphere that are impossible through brightness-only observations. in this pre... | mapping exoplanet clouds with high-dispersion spectro-polarimetry |
we present results taken from a study aiming at detecting the emission from relativistic particles jets in neutron star-low mass x-ray binaries using optical polarimetric observations. first, we focus on a polarimetric study performed on the persistent lmxb 4u 0614+091. once corrected for interstellar effects, we measu... | searching for jet emission in lmxbs: a polarimetric view |
starlight polarization provides insight into the physical mechanisms in and around the source as well as its geometry, whether or not the source is resolved. in this talk we will review mechanisms that polarize light in stellar envelopes. the observations and modeling can be used to probe the physics of the circumstell... | circumstellar polarimetry |
polarization is a potentially powerful, but underutilized, tool for understanding interstellar, circumstellar environments. to accurately interpret dust-induced polarization, in terms of magnetic fields and other environmental parameters, a quantitative understanding of the alignment of the dust grains is, however, req... | sofia/hawc+ polarization in the envelope of irc+10216 |
magnetic fields and turbulent flows pervade the interstellar medium on all scales. the magnetic turbulence that emerges on the large scales cascades towards the small scales where it influences molecular cloud structure, and star formation within the densest and coldest clumps of the clouds. active star formation resul... | magnetic phenomena of the interstellar medium in theory and observation |
the motion of diamagnetic dust particles in interstellar magnetic fields is studied numerically with several different sets of parameters. two types of behaviour are observed, depending on the value of the critical number r, which is a function of the grain inertia, the magnetic susceptibility of the material and of th... | on interstellar light polarization by diamagnetic silicate and carbon dust in the infrared |
hawc+, a second-generation sofia instrument designed to map far-infrared intensity and polarization, was commissioned in late 2016 and made first science observations in sofia cycles 4 and 5. we describe basic characteristics of the instrument, report on the commissioning flights and data analysis pipeline, and show so... | first results on interstellar magnetic fields from the hawc+ instrument for sofia |
the interstellar medium is suffused with magnetic fields, which inform the shape of structures in the diffuse gas. recent high-dynamic range observations of galactic neutral hydrogen, combined with novel data analysis techniques, have revealed a deep link between the morphology of neutral gas and the ambient magnetic f... | galactic neutral hydrogen and the magnetic ism foreground |
we have compiled the all-sky data on optical interstellar linear polarization from 13 data sources for 6420 stars without considerable intrinsic polarization from gaia dr2 within 500 pc from the sun. we display these data versus the stellar reddening estimates from five 3d maps and models. we have considered variations... | interstellar polarization in the local bubble and the gould belt based on gaia dr2 data |
studying the interaction between the interstellar medium and the black hole environment on the parsec scale is of crucial importance in the full understanding of galaxy evolution. since the galactic centre is the closest galactic nucleus, it offers us the unique possibility to observationally study the dynamics of indi... | interaction between interstellar medium and black hole environment |
the galway astronomical stokes polarimeter (gasp) is a high time resolution, full-stokes imaging polarimeter which utilises a fresnel rhomb prism as a beam-splitter and quarter wave retarder. the ability to perform optical photometry and polarimetry at high frame rates enables more detailed studies of a multitude of co... | high time resolution astronomical polarimetry with gasp |
identification of methyl acetate in the interstellar medium (ism) and its spectroscopic studies have prompted us to investigate the structure of crystalline methyl acetate using numerical calculations. here, we present a theoretical study of the structure of crystalline methyl acetate and its isotopologues and compare ... | theoretical study of the infrared frequencies of crystalline methyl acetate under interstellar medium conditions |
the synthesis telescope (st) at the dominion radio astrophysical observatory (drao) is the premier telescope in the world for imaging of large-scale neutral hydrogen and polarized radio continuum emission at arcmin resolution. a seven-element radio interferometer, its most prominent achievement to date is the completio... | drao synthesis telescope |
the origin of large-scale magnetic fields, detected in some low-mass (dwarf and irregular) galaxies via polarised synchrotron emission and faraday rotation, has remained unexplained for a long time. we suggest that mean-field dynamos can be active in galaxies of this class despite their slow rotation because their disc... | the origin of large-scale magnetic fields in low-mass galaxies |
the nika2 polarization channel at 260 ghz (1.15 mm) has been proposed primarily to observe galactic star-forming regions and probe the critical scales between 0.01-0.05 pc at which magnetic field lines may channel the matter of interstellar filaments into growing dense cores. the nika2 polarime-ter consists of a room t... | observing with nika2pol from the iram 30m telescope : early results on the commissioning phase |
the polarized instrument for long-wavelength observation of the tenuous interstellar medium (pilot) is a balloon-borne astronomy experiment designed to study the linear polarization of the far infra-red emission, 240 ~im (1.2 thz) and 550 ~tm (545 ghz) with an angular resolution of a few minutes of arc, from dust grain... | pilot end-to-end calibration results |
the highly filamentary structure of the interstellar medium (ism) is now impressively revealed by herschel and planck images. previous observations have shown that clouds are filamentary, however, only recently the mapping capabilities of herscheland planck have discovered their ubiquity in the ism. in particular, hers... | properties of interstellar filaments derived from herschel, planck, and molecular line observations |
sensitive, high resolution observations of galactic neutral hydrogen (hi) reveal an intricate network of slender linear features, much as sensitive surveys of dust in galactic molecular clouds reveal ubiquitous filamentary structure. across the high galactic latitude sky, diffuse histructures are aligned with the inter... | quantifying the magnetic alignment of hi and dust in the diffuse ism |
we use radio-continuum all-sky surveys at 1420 and 408 mhz with the aim to investigate properties of the galactic radio source lupus loop. the survey data at 1435 mhz, with the linear polarization of the southern sky, are also used. we calculate properties of this supernova remnant: the brightness temperature, surface ... | snr radio spectral index distribution and its correlation with polarization. a case study: the lupus loop |
this paper reports the results of new chemical modelling measurements of the faraday rotation braking mechanism operating on a diamagnetic molecule in a magnetic field. the time length of the experiment is extended, more relevant variables are measured (rotation, vibration, drift energies; molecule orientation), and mo... | on the alignment of diamagnetic molecules in interstellar magnetic fields |
aims: the interstellar polarization in the northern high-latitude sky is low and rather smooth in the local spiral (ls) longitude range 60° < l < 240°, except for an extension of aligned higher polarization within 120° < l < 180° up to b ≈ 50°. we compare this view with results from other indicators of inte... | on high-latitude interstellar polarization toward the local spiral |
recent herschel and planck observations of submillimeter dust emission revealed the omnipresence of filamentary structures in the interstellar medium (ism). the ubiquity of filaments in quiescent clouds as well as in star-forming regions indicates that the formation of filamentary structures is a natural product of the... | properties of interstellar filaments as derived from herschel, planck, and molecular line observations |
we present ubvri polarimetric observations of 66 stars in the direction of ngc 4755, including eleven β cephei stars. about half of these variables show indications of intrinsic polarization, but according to the theory neither radial nor non-radial pulsations could cause such polarizations. from the main characteristi... | multicolor ubvri polarimetry of ngc 4755 and the β cephei population |
recent observations of synchrotron emission in protostellar jets are important because they allow us to determine the jet and/or the interstellar magnetic field structure, thus giving insights on the jet ejection and collimation mechanisms. in this proceeding, we show the results obtained from the analysis of polarized... | simulación de jets protoestelares |
the rotation measure (rm) map we present here was calculated using stokes q and u data from the canadian galactic plane survey polarisation dataset. the data were observed using the dominion radio astrophysical observatory synthesis telescope as part of the cgps, in 4 frequency channels centred at 1407.2, 1414.1, 1427.... | vizier online data catalog: faraday rotation of extended emission (ordog+, 2019) |
this dissertation talk presents a new single-shot, full-stokes optical polarimeter using stress-engineered optics (seos), the first in the field of astronomy to do so (wolfe et al. 2018, proc. spie 107063b) . seos are cylindrical glass windows under static stress by radially inward forces in three symmetrically-spaced ... | simultaneous full-stokes polarimetry with stress-engineered optics |
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