abstract stringlengths 3 192k | title stringlengths 4 857 |
|---|---|
the fornax dwarf spheroidal galaxy is the most massive satellites of the milky way, claimed to be embedded in a huge dark matter halo, and the only among the milky way satellites hosting five globular clusters. interestingly, their estimated masses, ages and positions seem hardly compatible with the presence of a signi... | globular clusters as tracers of the host galaxy mass distribution: the fornax dsph test case |
samples of reliably identified halo wide binaries are scarce. if reasonably free from selection effects and with a small degree of contamination by chance alignments, these wide binaries become a powerful dynamical tool, having provided one of the very few experiments capable of constraining the nature of dark matter i... | a distant sample of halo wide binaries from sdss |
it has been suggested that a huge amount of baryon resides in the circumgalactic medium (cgm) extending out to the virial radii of galaxies. in this work we attempt to measure the baryon mass in the cgm with a novel method based on the gamma-ray observations of the extended halo of the andromeda galaxy messier 31 (m31)... | measuring the mass of missing baryons in the halo of andromeda galaxy with gamma-ray observations |
although the standard cosmological model, the so-called λ cold dark matter (λcdm), appears to fit well observations at the cosmological level, it is well known that it possesses several inconsistencies at the galactic scales. in order to address the problems of the λcdm on a small scale, some alternative models have be... | consequences for the scalar field dark matter model from the mcgaugh observed-baryon acceleration correlation |
the shape distortion of the presumed milky way dark matter halo can impact the local density of dark matter and thus the direct detection program. we examine the population of galactic rotation curves measured by sparc and fit them to dark matter haloes that are distorted with a multipole density distribution, finding ... | dark-matter halo shapes from fits to sparc galaxy rotation curves |
we study a set of solar neighborhood (d < 3 kpc) stars from gaia data release 2 to determine azimuthal star count differences, i.e., left and right of the line from the galactic center (gc) through the sun - and compare these differences north and south. in this companion paper to gardner et al., we delineate our pr... | probing axial symmetry breaking in the galaxy with gaia data release 2 |
the shape and orientation of dark matter (dm) halos are sensitive to the microphysics of the dm particles, yet in many mass models, the symmetry axes of the milky way's dm halo are often assumed to be aligned with the symmetry axes of the stellar disk. this is well motivated for the inner dm halo, but not for the outer... | orientations of dark matter halos in fire-2 milky way-mass galaxies |
we develop a comprehensive study of the gamma-ray flux observed by the high energy stereoscopic system (h.e.s.s.) in 5 regions of the galactic center (gc). motivated by previous works on a possible dark matter (dm) explanation for the tev cut-off observed by h.e.s.s. in the innermost ~ 15 pc of the galaxy, we aim to co... | multi-tev dark matter density in the inner milky way halo: spectral and dynamical constraints |
we analyse stellar streams in action-angle coordinates combined with recent local direct acceleration measurements to provide joint constraints on the potential of our galaxy. our stream analysis uses the kullback-leibler divergence with a likelihood analysis based on the two-point correlation function. we provide join... | building an acceleration ladder with tidal streams and pulsar timing |
we propose a new method for determining the shape of the gravitational potential of the dark matter (dm) halo of the milky way (mw) with the galactocentric tangential velocities of a sample of hypervelocity stars (hvss). we compute the trajectories of different samples of hvss in a mw where the baryon distribution is a... | probing the shape of the milky way dark matter halo with hypervelocity stars: a new method |
the axion is an unusually well motivated dark matter candidate which is the goldstone boson associated with spontaneous breaking of the pq symmetry of qcd. i describe an experiment to search for axions in our galactic halo using a high q resonant cavity coupled to ultra-low-noise receiver electronics. i discuss the ana... | a search for halo axions |
we develop a linear perturbative formalism to compute the response of an inhomogeneous stellar disk embedded in a nonresponsive dark matter (dm) halo to various perturbations like bars, spiral arms, and encounters with satellite galaxies. without self-gravity to reinforce it, the response of a fourier mode phase mixes ... | a comprehensive perturbative formalism for phase mixing in perturbed disks. ii. phase spirals in an inhomogeneous disk galaxy with a nonresponsive dark matter halo |
two alternative theories to dark matter are investigated by testing their ability to describe consistently the dynamics of the milky way. the first one refers to a modified gravity theory having a running gravitational constant and the second assumes that dark matter halos are constituted by a bose-einstein condensatio... | testing two alternative theories to dark matter with the milky way dynamics |
for the first time, we use the gamma-ray burst monitor (gbm) on-board the fermi satellite to search for sterile neutrino decay lines in the energy range 10-25 kev corresponding to sterile neutrino mass range 20-50 kev. this energy range has been out of reach of traditional x-ray satellites such as chandra, suzaku, xmm-... | improved limits on sterile neutrino dark matter from full-sky observations by the fermi-gbm |
directional dark matter detection attempts to measure the direction of motion of nuclei recoiling after having interacted with dark matter particles in the halo of our galaxy. due to earth's motion with respect to the galaxy, the dark matter flux is concentrated around a preferential direction. an anisotropy in the rec... | inverted dipole feature in directional detection of exothermic dark matter |
recent advancements in astrometry and in cosmological models of dark matter halo growth have significantly changed our understanding of the dynamics of the local group. the most dramatic changes owe to a new picture of the structure and dynamics of the milky way's most massive satellite galaxy, the large magellanic clo... | the lmc vs. the milky way |
in order to explain galactic structures, a self-gravitating system composed of massive fermions in spherical symmetry is considered. the finite mass distribution of such a component is obtained after solving the einstein equation for a thermal and semi-degenerate fermionic gas, described by a perfect fluid in hydrostat... | galactic constraints on fermionic dark matter |
strong dark matter interactions are proposed to alleviate the tension between observations and theoretical predictions in cdm. among different interaction channels, self-interacting dark matter (sidm) models have received considerable attention. however, most models and simulations have so far neglect the contribution ... | the abundance and dark matter structure of galaxies in self-interacting dark matter models |
stellar streams, produced by the tidal disruption of dwarf galaxies and globular clusters, yield a snapshot of hierarchical structure formation, and are powerful probes of the mass and profile of the milky way's dark matter halo, as well as the formation of its stellar halo. over the last several years, large imaging s... | highlights from the southern stellar stream spectroscopic survey |
we present the results of the shaft experiment to search for axion-like dark matter in the mass range from 12 pev to 12 nev. the experiment is sensitive to the oscillating magnetic field that would be sourced by an axion-like dark matter halo of our galaxy interacting with a strong static magnetic field in the lab. we ... | search for halo axions with ferromagnetic toroids (shaft experiment) |
the gaia mission has transformed our understanding of the milky way halo. in this talk, i will discuss the recent progress made in galactic halo science since the first astrometric gaia data release and future prospects. this includes the discovery and characterization of the last massive merger event (i.e. gaia-encela... | the galactic halo in the gaia era |
understanding the assembly history and dark matter distribution of our milky way (mw) is a major challenge for astrophysics. thanks to the unique capabilities of hst, proper motions of satellite galaxies, globular clusters and stellar streams have been measured with accuracies of order 0.05 mas/yr ( 10 km/s) at distanc... | new models of the milky way's dark matter distribution for the era of high precision astrometry |
the local dark matter density encodes valuable information about the local shape of the milky way's dark matter halo near the plane, providing constraints on galaxy formation models, the merger history of the galaxy and even alternative gravity theories. we present an ongoing exploration of the vertical and radial kine... | anisotropies in the local velocity field of the galactic disk and the local dark matter density |
the extragalactic background light (ebl) is the aggregate emission from all extragalactic sources throughout cosmic time. the cosmic infrared background experiment-1 (ciber-1) is a sounding rocket experiment optimized for probing ebl at near-infrared wavelengths, and it has flown four times from 2009 to 2013. a previou... | studying near-infrared intra-halo light with ciber mission |
methods of measuring distances to objects in our milky way are briefly discussed. they generally base on three principles: of using a standard rod, of standard candle and of column density of interstellar matter. weak and strong points of these methods are presented. the presence of gray extinction towards some objects... | how far is it? distance measurements and their consequences |
a modified circular velocity law is presented for a test body orbiting around a spherically symmetric mass. this law exhibits a distance scale parameter and allows to recover both usual newtonian behaviour for lower distances and a constant velocity limit at large scale. application to the galaxy predicts the known beh... | modified circular velocity law |
the sagittarius dwarf galaxy (sgr) is among the most massive satellites of the milky way and is unique due to its extensive tails of tidally stripped stars. these tails provide strong constraints on the orbital history of sgr, which in turn lend insight into the structure of the milky way's dark matter halo. utilizing ... | spitzer merger history and shape of the galactic halo: the distance to the core of the sagittarius dwarf galaxy from the mid-infrared period-luminosity relation for rr lyrae variable stars |
the macro-scale properties of dark matter (dm) haloes, such as shape and orientation, rely on the micro-physics of the dark matter particle. yet the symmetry axes of the milky way's dark matter halo are often assumed to be aligned with the symmetry axes of the stellar disc. while this is the likely case for the inner r... | orientations of dark matter haloes in cdm and sidm latte galaxies |
several multiferroic materials have axion-like modes that resonate with terahertz frequency electromagnetic waves. axions from the local dark matter halo of the galaxy allows such excitations to absorb mid-infrared light with wavelength near 2.44 microns and to raman scatter visible light with wavenumber shift near 410... | seeing dark matter in multiferroics with infrared and raman haloscopy |
the transition from linear to non-linear structure formation in cosmology is here studied from the point of view of the thermodynamics of self-gravitating fermions. we start by reviewing the principle of maximum entropy production through which such a fermionic system can relax towards spherical equilibrium states able... | dark matter fermions:from linear to non-linear structure formation |
the oc stream is a dwarf galaxy stream and is one of the longest and best-measured streams in the galaxy, spanning over 200 degrees on the sky. it extends from the inner milky way (~15 kpc) to the outer halo (~60 kpc), giving us a great tool with which to measure our galaxy's dark matter halo. in addition, portions of ... | the oc stream's evolution in the dark matter haloes of the milky way and the lmc |
inside the local group, the satellite galaxies of the milky way don't have an isotropic distribution, instead most of them lie on structure almost perpendicular to the plane of the disk of the galaxy, called vpos. at present there is not a theoretical model that correctly explain both the abundance and spatial distribu... | fall of associations of dwarf galaxies into the milky way halo |
axions saturate the local dark matter halo of the galaxy and have rest energy in the sub-millimeter range. in this frequency range, topological density wave materials, such as, topological insulators in the spin density wave phase (sdw) and weyl semi-metals in the charge density wave phase (cdw), are usually transparen... | catching axions with density waves |
self-interacting dark matter (sidm) can create sufficiently large cores in dark matter haloes of dwarf galaxies if the self-interaction cross-section is sufficiently large on scales of dwarf galaxies. such a large cross-section can be realized without changing the densities and shapes of cluster-size haloes by introduc... | structure of dark matter haloes of milky way satellite galaxies in sidm universes |
an excess of gamma rays from the inner galaxy in the fermi lat data has been identified. this emission has been interpreted as a possible signature of the annihilation of dark matter particles, or as originating from a collection of unresolved point sources, such as gamma-ray millisecond pulsars. we explore the cluster... | dark matter or point sources? utilizing the 1-pt pdf to understand the origin of the gev excess seen by the fermi lat detector |
directly linked to the mass of the dark matter halo where baryons form, the galaxy stellar mass (m_star) is the most important observable parameter to understand galaxy evolution. still, we have not completely figured out how the growth of the stellar mass in galaxies happen. a fundamental problem stands at the fact th... | the origin of bulges and discs. the stellar mass growth unveiled using califa spectro-photometric decompositions |
the dark matter halos surrounding milky way-like galaxies that are formed in cosmological simulations are triaxial. these simulated triaxial halos are expected to be slowly rotating with log-normal distribution of pattern speeds centered on ~0.148h km/s/kpc (bailin & steinmetz 2004, apj., 616, 27). stellar streams ... | using tidal streams to investigate the rotation of the milky way's dark matter halo |
the paper discusses existing methods of distance determinations to bright objects inside our galaxy. possible inaccuracies are considered. measurements of both: distances and radial velocities allow determination of the milky way rotation curve, believed to be at because of the postulated dark matter halo around the ga... | distance measurements towards young milky way objects; rotation curve |
the large magellanic cloud (lmc), the most massive satellite of the milky way(mw), is perturbing the dynamics and equilibrium of the mw. understanding thenature and time evolution of these perturbations remains one of the most importantchallenges to the interpretation of 6d phase space measurements of tracers (satel-li... | the effect of the large magellanic cloud on the dark matter halo of the milky way |
the connection between dark matter haloes and galaxies describes the galaxy formation process in the dark matter field. it is crucial for modelling galaxy clustering on small scales and constructing high-fidelity large-scale simulations for galaxies. the early data release (edr) of desi is a powerful dataset for unders... | desi early data release: galaxy-dark-matter-halo connection |
the dark matter halos that surround milky way-like galaxies in cosmological simulations are, to first order, triaxial. such halos are predicted to exhibit steady figure rotation with a median pattern speed 0.15h km/s/kpc ~ 0.15h radian/gyr. the pattern speeds predicted by cosmological cdm simulations are so small that ... | using tidal streams to probe the figure rotation of the milky way's dark matter halo |
the length asymmetry of the tidal stellar stream palomar 5 could have been caused by a past encounter(s) with the galactic bar, thus limiting its use as a probe for structures in the dark matter halo of the milky way. | mind the galactic bar |
galaxies live in dark matter haloes and hence the galaxy properties are majorly defined by the properties of the haloes. thus the environmental dependence of dark matter halo properties prompts a correlation between galaxy properties and the environment. more insights into these environmental correlations are crucial f... | environmental dependence of galaxy properties using marked statistics |
glon sky survey is a data acquisition method of 21 cm neutral hydrogen spectrum. recently, the author has conducted a series of studies on the data of the glon sky survey. after transforming and analyzing the data, the author found that in the region of the center of the milky way galaxy, the linear velocity of galacti... | research on the galaxy rotation model based on 21 cm hydrogen spectrum |
the stars of the s-cluster orbiting the galactic center provide one of the best astrophysical observables to infer the gravitational potential generated by the central source sgr a*, traditionally assumed to be a black hole (bh). an alternative model for sgr a* is the ruffini- argüelles-rueda (rar) model, based on a se... | testing the nature of sgr a* with the s-2 star orbit data |
in the outer reaches of galaxies, stars dont move quite how they should. is this deviation due to mysterious dark matter? or is something else at work? in a recent study, scientists turn to elliptical galaxies in search of new clues.weirdness in galactic fringestwo rotating galaxies are shown with their rotation curves... | searching for universal acceleration |
we describe an algorithm that can fit the properties of the dwarf galaxy progenitor of a tidal stream, given the properties of that stream. we show that under ideal conditions (the milky way potential, the orbit of the dwarf galaxy progenitor, and the functional form of the dwarf galaxy progenitor are known exactly), t... | streams and the milky way dark matter halo |
the macro-scale properties of dark matter (dm) halos, including their shape and orientation, are sensitive to the micro-physics of the dark matter particle. yet in many cases, the symmetry axes of the milky way's dark matter halo are often assumed to be aligned with the symmetry axes of the stellar disk when modeling t... | orientations of dark matter halos in cdm and sidm latte galaxies |
nimble (non-parametric jeans modeling with b-splines) inferrs the cumulative mass distribution of a gravitating system from full 6d phase space coordinates of its tracers via spherical jeans modeling. it models the milky way's dark matter halo using gaia and dark energy spectroscopic instrument milky way survey (desi m... | nimble: non-parametric jeans modeling with b-splines |
the mass and cumulative mass profile of the milky way's dark matter halo is a fundamental property of the galaxy, and yet these quantities remain poorly constrained and span almost two orders of magnitude in the literature. there are a variety of methods to measure the mass of the milky way, and a common way to constra... | bayesian mass estimates of the milky way: inferring the mass profile from globular cluster kinematics |
the axion was introduced over forty years ago to explain the apparent symmetry of the strong nuclear force under time-reversal tand space inversion p. later, it became a leading dark matter candidate when laboratory searches indicated its decay constant is large compared to the electroweak symmetry breaking scale. yet,... | weighing the axion with muon haloscopy |
the keplerian distribution of velocities is not observed in the rotation of large scale structures, such as found in the rotation of spiral galaxies. the deviation from keplerian distribution provides compelling evidence of the presence of non-luminous matter i.e. called dark matter. there are several astrophysical mot... | dark matter and neutrinos |
based on the recently discovered correlations between the half-light radii and dark matter halo parameters of milky way dwarf spheroidal galaxies, we infer the initial distributions of baryonic and dark matter in the first galaxies. | inferring the initial mass distributions of the first galaxies from observed correlations between the half-light radii and dark matter halo parameters of milky way dwarf spheroidals |
dark matter and dark energy comprise most of the energy density of the universe; however, we know very little about either of them. we have only seen their effects on astrophysics and cosmology, and these remain the best ways to test these theories. i have focused my dissertation on testing various dark matter and dark... | constraining self-interacting dark matter with galaxy warps |
for over three decades cosmological simulations have predicted the properties of dark matter in the cold dark matter (cdm) paradigm. most observational efforts have focused on verifying the small-scale predictions of cdm. despite significant advances in understanding the milky way in the context of the prevailing lcdm ... | exploring the nature of dark matter with gaia |
we propose to measure the proper motion (pm) of m31 stars to unprecedented precision, using multi-epoch hst data of seven acs/wfc fields. our first goal is to measure m31's mean tangential motion with a precision nearly triple that of the previous hst and gaia measurements. the better-determined center-of-mass (com) mo... | resolved proper motions of m31 and the m31-m32 interaction |
every field observed more than once by the wfirst telescope is an astrometric survey. this includes the high-latitude survey fields, which span several thousand square degrees. the large synoptic space telescope will identify rr lyrae stars with extremely accurate distance measurements to beyond the virial radius of th... | wfirst: mapping the milky way’s dark matter halo with wfirst astrometry |
an excess of gamma rays from the inner galaxy in the fermi lat data has been identified. this emission has been interpreted as a possible signature of the annihilation of dark matter particles, or as originating from a collection of unresolved point sources, such as gamma-ray millisecond pulsars. we explore the cluster... | dark matter or point sources? utilizing the 1-pt pdf to understand the origin of the gev excess seen by the fermi lat detector |
the current cosmological paradigm predicts that dark matter halos are triaxial overall, but oblate in regions where baryons dominate. however recent measurements of the shape of the milky way dark matter halo find it to be very triaxial with a shape and orientation that are significantly at odds with theoretical predic... | using accurate phase space coordinates of ~100,00 halo field stars to constrain the milky way halo |
x-ray observations of nearby clusters and galaxies have reported an unexpected x-ray line around 3.5 kev. this line has received significant attention due to its possible explanation through decaying dark matter; in particular, decaying sterile neutrino models, with a sterile neutrino mass around 7 kev, provide a good ... | evidence the 3.5 kev line is not from dark matter decay |
with its observations over 2/3 of the sky every day, the high altitude water cherenkov (hawc) observatory is sensitive to a wide variety of astrophysical sources, including possible gamma rays from dark matter. dark matter annihilation and decay in the dark matter halo of the milky way galaxy should produce gamma-ray s... | searches for dark matter in the galactic halo with the high altitude water cherenkov observatory |
we incorporate milky way dark matter halo profile uncertainties, as well as an accounting of diffuse gamma-ray emission uncertainties in dark matter annihilation models for the galactic center extended gamma-ray excess (gce) detected by the fermi gamma ray space telescope. the range of particle annihilation rate and ma... | implications of tension between observations of the bright galactic center excess and dim dwarf galaxies |
one of the most exciting recent results in the field of dark matter indirect searches has been the discovery of an excess emission in gamma rays from the galactic centre above the standard astrophysical background. we show that current hydrodynamic simulations, namely simulated milky way-like galaxies within the “evolu... | the fermi gev excess: challenges for the dark matter interpretation |
the axion is a hypothetical elementary particle arising in the 1970's from an elegant solution to the strong cp problem in quantum chromo dynamics. light qcd axions (masses <10-3 ev/c2) would have extraordinarily feeble interactions with normal matter and radiation, and these axions have the properties of an ideal d... | searching for dark-matter axions |
the origin of the satellite disc of the milky way (dos or vpos) and m31 (gpoa) remains an open problem in astrophysics (klypling, kravtsov, & valenzuela, 1999; pawlowski, kroupa, & jerjen, 2013). this paper presents a study on the possible formation of the milky way satellite disc from an association of dwarf g... | infall of associations of dwarf galaxies into the milky way halo |
a wealth of astrophysical and cosmological observational evidence shows that the matter content of the universe is made of about 85$\%$ of non-baryonic dark matter. huge experimental efforts have been deployed to look for the direct detection of dark matter via their scattering on target nucleons, their production in c... | sensitivity to kev-mev dark matter from cosmic-ray scattering with current and the upcoming ground-based arrays cta and swgo |
our current understanding of how dark matter (dm) is distributed within the milky way (mw) halo, particularly in the solar neighborhood, is based on either careful studies of the local stellar orbits or model assumptions on the global shape of the mw halo. in this work, we undertake a study of external galaxies, with t... | dark matter distribution in milky way-analog galaxies |
stellar streams are sensitive tracers of the gravitational potential, which is typically assumed to be static in the inner galaxy. however, massive mergers like gaia-sausage-enceladus can impart torques on the stellar disk of the milky way that result in the disk tilting at rates of up to 10-20 deg/gyr. here, we demons... | slant, fan, and narrow: the response of stellar streams to a tilting galactic disk |
recent measurements of muon spin precession confirm a long-standing tension with the standard model of particle physics. we argue that axions from the local dark matter halo of the galaxy are responsible for the tension. the argument yields a percent level prediction for the mass of the axion provided that dark matter ... | weighing the axion with muon haloscopy |
we report the detection of a 282 $^{+34}_{-31}$ pc-sized core in the center of milky way dark matter halo at $68\%$ confidence level by using the micro-lensing event rate sky map data from the optical gravitational lensing experiment (ogle) survey. we apply the spacial information of the micro-lensing sky map and model... | a $\\sim$300 pc-sized core of milky way dark matter halo constrained from the ogle micro-lensing sky map |
ecosystems are responding to climate change and increasing atmospheric co2 concentrations. interactions between these factors have rarely been assessed experimentally during and after extreme climate events despite their predicted increase in intensity and frequency and their negative impact on primary productivity and... | elevated co2 maintains grassland net carbon uptake under a future heat and drought extreme |
the colorado ultraviolet transit experiment (cute) is a 6u nasa cubesat carrying on-board a low-resolution, near-ultraviolet (2479-3306 å) spectrograph. it has a cassegrain telescope with a rectangular primary to maximize the collecting area, given the shape of the satellite bus, and an aberration correcting grating to... | the autonomous data reduction pipeline for the cute mission |
the absorption of stellar radiation observed by hd 209458b in the resonant lines of o i and c ii has not yet been satisfactorily explained. we apply a 2d hydrodynamic multi-fluid model that self-consistently describes the expanding planetary wind, driven by stellar xuv radiation and influenced by tidal forces and the s... | modeling of absorption by heavy minor species for the hot jupiter hd 209458b |
the magnetic fields of the solar system's planets provide valuable insights into their interiors and can have dramatic consequences for the evolution of their atmospheres and interaction with the solar wind. however, we have little direct knowledge of magnetic fields in exoplanets. here we present a method for detectin... | detecting magnetic fields in exoplanets with spectropolarimetry of the helium line at 1083 nm |
we estimate the contribution of the molecular hydrogen dissociation processes, which are induced by the extreme uv radiation and the accompanying flux of photoelectrons, to the formation of a fraction of suprathermal atomic hydrogen in the h2 → h transition region and the corresponding escape flux from the extended upp... | nonthermal atmospheric loss of the exoplanet gj 436b due to h2 dissociation processes |
observations of extended atmospheres around hot planets have generated exciting results concerning the dynamics of escaping planetary material. the configuration of the escaping planetary gas can result in asymmetric transit features, producing both pre- and post-transit absorption in specific atomic transitions. measu... | a search for hα absorption around kelt-3 b and gj 436 b |
hydrogen and helium transmission signals trace the upper atmospheres of hot gas-giant exoplanets, where the incoming stellar extreme ultraviolet and x-ray fluxes are deposited. further, for the hottest stars, the near-ultraviolet excitation of hydrogen in the balmer continuum may play a dominant role in controlling the... | detection of paschen β absorption in the atmosphere of kelt-9 b. a new window into the atmospheres of ultra-hot jupiters |
we develop platypos (planetary photoevaporation simulator), a python code to perform planetary photoevaporative mass-loss calculations for close-in planets with hydrogen-helium envelopes atop earth-like rocky cores. with physical and model parameters as input, platypos calculates the atmospheric mass loss and with it t... | estimating photoevaporative mass loss of exoplanets with platypos |
we propose a new method to estimate ion escape from unmagnetized planets that combines observations and models. assuming that upstream solar wind conditions are known, a computer model of the interaction between the solar wind and the planet is executed for different ionospheric ion production rates. this results in di... | estimating ion escape from unmagnetized planets |
numerous exoplanets with masses ranging from earth to neptune and radii larger than earth have been found through observations. these planets possess atmospheres that range in mass fractions from 1% to 30%, reflecting the diversity of atmospheric mass fractions. such diversities are supposed to be caused by differences... | giant impact events for protoplanets: energetics of atmospheric erosion by head-on collision |
one of the most well-studied exoplanets to date, hd 189733 b, stands out as an archetypal hot jupiter with many observations and theoretical models aimed at characterizing its atmosphere, interior, host star, and environment. we report here on the results of an extensive campaign to observe atmospheric escape signature... | hydrodynamic atmospheric escape in hd 189733 b: signatures of carbon and hydrogen measured with the hubble space telescope |
photoevaporation is a potential explanation for several features within exoplanet demographics. atmospheric escape observed in young neptune-sized exoplanets can provide insight into and characterize which mechanisms drive this evolution and at what times they dominate. au mic b is one such exoplanet, slightly larger t... | the variable detection of atmospheric escape around the young, hot neptune au mic b |
the 2006 guinsaugon landslide in saint bernard, southern leyte, is one of the largest known landslides in the philippines in recent history. it consists of a 15-20 million m3 rockslide-debris avalanche from an approximately 675 m high mountain weakened by continuous movement of the philippine fault. the catastrophic gu... | hazard mapping related to structurally controlled landslides in southern leyte, philippines |
4 debris avalanches pose some of the most destructive geologic hazards that threaten both 5 urban and rural populations around the world. on 20 september 2018, villages in naga city, 6 cebu, philippines, were devastated by a landslide that claimed 78 lives with 6 missing, joining 7 other catastrophic landslides in the ... | anatomy of the naga city landslide and comparison with historical debris avalanches and analog models |
the rotation of the interplanetary magnetic field (imf) provides details of the escape mechanism that varies with the interaction between the intrinsic magnetic field and the imf. a multispecies magnetohydrodynamic simulation is conducted on a mars-like planet under the conditions of a weak intrinsic magnetic field and... | enhanced ion escape rate during imf rotation under weak intrinsic magnetic field conditions on a mars-like planet |
we investigate the atmospheric and magnetospheric conditions of the massive, close-in exoplanet υ andromedae b (hereafter ups and b). in particular, we explore whether radio emission can be produced by the cyclotron maser instability (cmi), and whether this emission can escape from its source region. for this, we compa... | can radio emission escape from the magnetosphere of υ andromedae b - a new method to constrain the minimum mass of hot jupiters |
we estimated the contribution of reactions of exothermic photochemistry, namely, the dissociation of molecular hydrogen, by extreme uv radiation and the accompanying flux of photoelectrons, to the formation of a fraction of suprathermal atomic hydrogen in the h2 → h transition region of the extended upper atmosphere of... | nonthermal atmospheric loss of the sub-neptune π men c due to exothermic photochemistry |
in this work, numerical estimates of the rate of nonthermal loss of the atmosphere of a hot exoplanet due to exothermic photochemical processes are obtained. as an example, calculations were made for the h2 → h transition region of the upper atmosphere of the hot neptune gj 3470b in the altitude range 1.6-2.05 rp. from... | nonthermal atmospheric losses for the exoplanet gj 3470b |
the 23 myr system v1298 tau hosts four transiting planets and is a valuable laboratory for exploring the early stages of planet evolution soon after formation of the star. we observe the innermost planet, v1298 tau c, during transit using lbt pepsi to obtain high spectral resolution characterization of escaping materia... | h-α variability of v1298 tau c |
the colorado ultraviolet transit experiment cubesat mission aims to observe atmospheric escape from a dozen or more exoplanets by monitoring them in the near-ultraviolet, explains principal investigator kevin france. | exploring extreme exoplanets |
atmospheric escape is an important sector in the evolution of planetary atmosphere, and its energy is mainly originated from the radiation of the host star at the high energy band. the radiation flux drops dramatically with the increase of orbital distance, there is a large difference of planetary atmospheric escape in... | effect of orbital distance on the atmospheric escape of exoplanets |
we adapted a multispecies escape model, developed for close-in extrasolar planets, to calculate the escape rates of ch4 and n2 from pluto. in the absence of escape, ch4 should overtake n2 as the dominant species below the exobase. the ch4 profile depends strongly on the escape rate, however, and the typical escape rate... | on the escape of ch4 from pluto's atmosphere |
sodium and potassium signatures in transiting exoplanets can be challenging to isolate from the stellar absorption lines. here, these challenges are discussed in the framework of solar system observations, and transits of mercury in particular. radiation pressure is important for alkali gas dynamics in close-orbiting e... | doppler-shifted alkali d absorption as indirect evidence for exomoons |
the population of known low- to intermediate-mass exoplanets shows a large spread in densities, which is believed to be due to the diversity of planetary atmospheres and thus controlled by planetary atmospheric mass loss. one of the main drivers of long-term atmospheric escape is the absorption of high-energy xuv radia... | stellar rotation and its connection to the evolution of hydrogen-dominated atmospheres of exoplanets |
driven by the high energy radiation of host stars, atmospheric escape is very important for planet evolution. while the flux drops dramatically with the increase of orbital distance, it is essential to study the impacts of orbital distance on atmospheric escape. we consider the hydrodynamic escape of exoplanets driven ... | the impacts of orbital distance on exoplanetary atmospheric escape |
the known populations of super-earths and sub-neptunes with orbital periods less than ~100 days have been shaped by atmospheric evaporation, leading to the observed radius valley near 1.7 earth radii. however, it is currently unclear what the dominant mass loss mechanism is for these planets. the two likely culprits ar... | measuring mass loss via metal lines from the very young planet au mic b |
exoplanets orbiting close to their parent stars have been observed to lose a fraction of their atmosphere into space: they "evaporate." the escape of atmospheric gas is due to the large x-ray to ultraviolet (xuv) energy input from the nearby host-star into the upper atmosphere of the planet. evaporation is characterize... | characterizing evaporating atmospheres of exoplanets |
we are moving from an era of exoplanet discovery into an era of exoplanet characterization, but small, potentially-rocky planets orbiting bright, nearby stars that are suitable for atmospheric characterization studies are relatively scarce. here we propose to obtain time series spectroscopy using wfc3/ir to test for de... | searching for secondary atmospheres in a system of benchmark worlds |
we present concept and laboratory demonstration of high-contrast apodization baffle for instruments to be carried on exploration missions of the solar system. the primary science objective of the high-contrast baffle is to reveal escape of atmosphere on mars, while other faint objects around blight sources are potentia... | high-contrast apodization baffle for instruments onboard solar system exploration missions |
in july 2015, we announced the discovery of the super-earth hd 219134b, orbiting a v = 5.57 star 6.5-pc away from us motalebi et al. 2015. it was the brightest and closest transiting system known so far. the density of hd 219134b is compatible with a rocky planet, possibly containing a large amount of volatile species.... | lyman alpha observations of the hd 219134 system: deuterium-to-hydrogen ratio of the local ism and the exosphere of the super-earth hd 219134b |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.