LARGE-SCALE EXTENDED EMISSION AROUND THE HELIX
... regions (PDRs) shows that the emission arises from thermal excitation of the hydrogen molecules in PDRs and not from shocks. The FIR observations, at 90 and 160 lm, represent mostly contributions from thermal dust emission from cool dust grains but include a small contribution from ionized atomic li ...
... regions (PDRs) shows that the emission arises from thermal excitation of the hydrogen molecules in PDRs and not from shocks. The FIR observations, at 90 and 160 lm, represent mostly contributions from thermal dust emission from cool dust grains but include a small contribution from ionized atomic li ...
Star Formation in the Orion Nebula II: Gas, Dust, Proplyds and
... stars not optically visible because of the high extinction caused by these objects falling within the PDR or the molecular cloud. In Sect. 5 we consider the outflows encountered, which range from microjets with scales of hundreds of astronomical units to large scale outflows with scales of parsecs. ...
... stars not optically visible because of the high extinction caused by these objects falling within the PDR or the molecular cloud. In Sect. 5 we consider the outflows encountered, which range from microjets with scales of hundreds of astronomical units to large scale outflows with scales of parsecs. ...
MASSIVE GALAXIES IN COSMOLOGICAL SIMULATIONS: ULTRAVIOLET-SELECTED
... We study the properties of galaxies at redshift z ¼ 2 in a cold dark matter (CDM) universe, using two different types of hydrodynamic simulation methods—Eulerian total variation diminishing (TVD) and smoothed particle hydrodynamics (SPH)—and a spectrophotometric analysis in the Un , G, R filter s ...
... We study the properties of galaxies at redshift z ¼ 2 in a cold dark matter (CDM) universe, using two different types of hydrodynamic simulation methods—Eulerian total variation diminishing (TVD) and smoothed particle hydrodynamics (SPH)—and a spectrophotometric analysis in the Un , G, R filter s ...
PDF file
... bundles and shear motion in the photosphere makes the coronal magnetic field much more complex and stores magnetic energy. Once a flare occurs, the stored huge energy is released into the solar atmosphere in a short time. As a result of the energy release, a lot of phenomena are observed in various ...
... bundles and shear motion in the photosphere makes the coronal magnetic field much more complex and stores magnetic energy. Once a flare occurs, the stored huge energy is released into the solar atmosphere in a short time. As a result of the energy release, a lot of phenomena are observed in various ...
Giant Molecular Clouds in Local Group Galaxies
... is a good value to use in most galaxies (except the SMC) if the GMCs are virialized. However, if the clouds are only marginally self-gravitating, as appears to be the case judging from their appearance, half the virial value may be more appropriate. There is no clear trend of XCO with metallicity. T ...
... is a good value to use in most galaxies (except the SMC) if the GMCs are virialized. However, if the clouds are only marginally self-gravitating, as appears to be the case judging from their appearance, half the virial value may be more appropriate. There is no clear trend of XCO with metallicity. T ...
Circumstellar Material in Young Stellar Objects
... correct today: stars form out of large clouds of gas (and dust) in interstellar space which collapse under the influence of their own gravity. However, after more than two centuries of research many important questions regarding the star formation process, and the fundamentals of planet formation, s ...
... correct today: stars form out of large clouds of gas (and dust) in interstellar space which collapse under the influence of their own gravity. However, after more than two centuries of research many important questions regarding the star formation process, and the fundamentals of planet formation, s ...
arXiv:1410.8731v2 [astro
... pink filled squares, respectively. The SgrA* position is marked with the big cross. The middle panels display the integrated spectrum at the DSO position (thick blue line) in comparison with the background spectra (thin pink line). The vertical dashed-line at 2.166 µm marks the spectral position of ...
... pink filled squares, respectively. The SgrA* position is marked with the big cross. The middle panels display the integrated spectrum at the DSO position (thick blue line) in comparison with the background spectra (thin pink line). The vertical dashed-line at 2.166 µm marks the spectral position of ...
Abstract Title of Dissertation: BLACK HOLE DYNAMICS AND GRAVITATIONAL RADIATION IN GALACTIC NUCLEI
... the centers of small galaxies are conducive environments for black hole mergers. These clusters have large escape velocities, high stellar densities, and large numbers of black holes that will have multiple close encounters, which often lead to mergers. We present simulations of the three-body dynam ...
... the centers of small galaxies are conducive environments for black hole mergers. These clusters have large escape velocities, high stellar densities, and large numbers of black holes that will have multiple close encounters, which often lead to mergers. We present simulations of the three-body dynam ...
The most metal-poor galaxies
... 1 Introduction – What is a metal-poor galaxy? The discovery of extragalactic objects with very low heavy element abundance was made by Searle and Sargent (1972) who reported on the properties of two intriguing galaxies, IZw18 and IIZw40. They emphasised that they could be genuinely young galaxies i ...
... 1 Introduction – What is a metal-poor galaxy? The discovery of extragalactic objects with very low heavy element abundance was made by Searle and Sargent (1972) who reported on the properties of two intriguing galaxies, IZw18 and IIZw40. They emphasised that they could be genuinely young galaxies i ...
Discovery and Study of Exotic Radio Pulsars Jason William Thomas
... characteristics of the globular cluster pulsar population in general, particularly the luminosity function. In observations of the rich, massive cluster Terzan 5 with the Green Bank Telescope we have discovered the 1.396-ms pulsar J1748−2446ad, which is now the fastest-spinning neutron star known. T ...
... characteristics of the globular cluster pulsar population in general, particularly the luminosity function. In observations of the rich, massive cluster Terzan 5 with the Green Bank Telescope we have discovered the 1.396-ms pulsar J1748−2446ad, which is now the fastest-spinning neutron star known. T ...
SDSS J105754. 25+ 275947.5: a period
... Key words: binaries: close - binaries: eclipsing - stars: dwarf novae - stars: individual: SDSS J105754.25+275947.5 - stars: cataclysmic variables - stars: brown dwarfs ...
... Key words: binaries: close - binaries: eclipsing - stars: dwarf novae - stars: individual: SDSS J105754.25+275947.5 - stars: cataclysmic variables - stars: brown dwarfs ...
The Green Valley is a Red Herring: Galaxy Zoo reveals two
... We use SDSS+GALEX+Galaxy Zoo data to study the quenching of star formation in lowredshift galaxies. We show that the green valley between the blue cloud of star-forming galaxies and the red sequence of quiescent galaxies in the colour-mass diagram is not a single transitional state through which mos ...
... We use SDSS+GALEX+Galaxy Zoo data to study the quenching of star formation in lowredshift galaxies. We show that the green valley between the blue cloud of star-forming galaxies and the red sequence of quiescent galaxies in the colour-mass diagram is not a single transitional state through which mos ...
11115002
... though the model of neutron stars were provided by Oppenheimer and Volkoff as early as 1939—who suggested that a neutron star was an ideal gas of free neutrons. Being extremely heavy particles by themselves, neutrons can account for the heavy mass of the neutron stars (~1014 g/cm3). It is believed t ...
... though the model of neutron stars were provided by Oppenheimer and Volkoff as early as 1939—who suggested that a neutron star was an ideal gas of free neutrons. Being extremely heavy particles by themselves, neutrons can account for the heavy mass of the neutron stars (~1014 g/cm3). It is believed t ...
Accretion Power in Astrophysics, Third Editiion
... The subject of this book is astrophysical accretion, especially in those circumstances where accretion is believed to make an important contribution to the total light of an astrophysical system. Our discussion therefore centres mainly on close binary systems containing compact objects and on active ...
... The subject of this book is astrophysical accretion, especially in those circumstances where accretion is believed to make an important contribution to the total light of an astrophysical system. Our discussion therefore centres mainly on close binary systems containing compact objects and on active ...
MUFASA: The assembly of the red sequence
... via mergers does not produce red and dead galaxies, since accretion and hence star formation restarts after 1–2 Gyr. Instead, a model where diffuse hot gas in massive halos is prevented from cooling was able to broadly reproduce observed galaxy colours and the red and blue galaxy mass functions (Gab ...
... via mergers does not produce red and dead galaxies, since accretion and hence star formation restarts after 1–2 Gyr. Instead, a model where diffuse hot gas in massive halos is prevented from cooling was able to broadly reproduce observed galaxy colours and the red and blue galaxy mass functions (Gab ...
spatially resolved star formation history of milky way satellites
... galaxies and their own satellites form a self-gravitating association called the Local Group, and hence, the satellite galaxies that reside in it are called local dwarf galaxies. Local dwarf galaxies are crutial for understanding several key aspects of modern astrophysics (Mateo, 1998; Tolstoy et al ...
... galaxies and their own satellites form a self-gravitating association called the Local Group, and hence, the satellite galaxies that reside in it are called local dwarf galaxies. Local dwarf galaxies are crutial for understanding several key aspects of modern astrophysics (Mateo, 1998; Tolstoy et al ...
Post-starburst galaxies: more than just an interesting curiosity
... spectra which identify them as having recently undergone a strong starburst and subsequent fast quenching of star formation. These post-starburst galaxies lie in the redshift range 0.5 < z < 1.0 with masses > 109.75 M⊙ . They have a number density of 1 × 10−4 per Mpc3 , almost two orders of magnitud ...
... spectra which identify them as having recently undergone a strong starburst and subsequent fast quenching of star formation. These post-starburst galaxies lie in the redshift range 0.5 < z < 1.0 with masses > 109.75 M⊙ . They have a number density of 1 × 10−4 per Mpc3 , almost two orders of magnitud ...
Plasmoid-induced-reconnection and fractal reconnection Kazunari Shibata and Syuniti Tanuma
... al., 1997), and Yohkoh has shown that giant arcades formed after prominence eruptions or CMEs are physically similar to flare arcades even though their total X-ray intensity is much lower than that of normal flares (e.g., Tsuneta et al., 1992b; Hanaoka et al., 1994). Figure 2 shows several examples ...
... al., 1997), and Yohkoh has shown that giant arcades formed after prominence eruptions or CMEs are physically similar to flare arcades even though their total X-ray intensity is much lower than that of normal flares (e.g., Tsuneta et al., 1992b; Hanaoka et al., 1994). Figure 2 shows several examples ...
Link - Max-Planck-Institut für Astronomie
... is identifying candidate FUors before they occur: V1057 Cyg is one of only two identified FUors (with HBC 722, discussed below) with a pre-outburst optical spectrum (Herbig, 1977). It was found to have optical emission lines typical of a TTS. Modern large spectral surveys of active starforming regio ...
... is identifying candidate FUors before they occur: V1057 Cyg is one of only two identified FUors (with HBC 722, discussed below) with a pre-outburst optical spectrum (Herbig, 1977). It was found to have optical emission lines typical of a TTS. Modern large spectral surveys of active starforming regio ...
A New Model without Dark Matter for the Rotation of Spiral Galaxies
... observation of the Seyfert galaxies NGC 7674, NGC 5506, NGC 2110 and Mrk 1210, and conclude that “Our results confirm and extend earlier work showing that the outward motion of rad io co mponents in Seyfert galaxies is non-relativistic on pc scale. We briefly discuss whether this non-relativistic mo ...
... observation of the Seyfert galaxies NGC 7674, NGC 5506, NGC 2110 and Mrk 1210, and conclude that “Our results confirm and extend earlier work showing that the outward motion of rad io co mponents in Seyfert galaxies is non-relativistic on pc scale. We briefly discuss whether this non-relativistic mo ...
THE RED-SEQUENCE LUMINOSITY FUNCTION IN GALAXY
... the properties and scaling relations of elliptical galaxies. In the current hierarchical paradigm, structure forms in a ‘‘bottom-up’’ sense, as galaxies and clusters are built from the merging of smaller units. Recently, there has been growing evidence that star formation has evolved in a ‘‘top-down ...
... the properties and scaling relations of elliptical galaxies. In the current hierarchical paradigm, structure forms in a ‘‘bottom-up’’ sense, as galaxies and clusters are built from the merging of smaller units. Recently, there has been growing evidence that star formation has evolved in a ‘‘top-down ...
Star Formation in the Milky Way and Nearby Galaxies Further
... of powerful new instruments on the Hubble Space Telescope (HST); and a host of ground-based optical, infrared (IR), submillimeter, and radio telescopes. These new observations are providing a detailed reconstruction of the key evolutionary phases and physical processes that lead to the formation of ...
... of powerful new instruments on the Hubble Space Telescope (HST); and a host of ground-based optical, infrared (IR), submillimeter, and radio telescopes. These new observations are providing a detailed reconstruction of the key evolutionary phases and physical processes that lead to the formation of ...
Chapter 6 in the LSST Science Book
... proximity of the Galaxy. Until recently, it was held that the Clouds are captive satellites of the Galaxy and have made several passages through the Galaxy disk. The extended stream of HI, called the Magellanic Stream, which emanates from near the SMC and wraps around much of the sky, has been belie ...
... proximity of the Galaxy. Until recently, it was held that the Clouds are captive satellites of the Galaxy and have made several passages through the Galaxy disk. The extended stream of HI, called the Magellanic Stream, which emanates from near the SMC and wraps around much of the sky, has been belie ...
The chemical composition of two supergiants in the dwarf
... dwarf irregular galaxies appear to have undergone bursts of star formation during their histories and thus should show a variety of α/Fe ratios throughout their evolution, but they are too distant for detailed analysis of their red giant branch (=RGB, stars that can sample ages >1 Gyr). It is possib ...
... dwarf irregular galaxies appear to have undergone bursts of star formation during their histories and thus should show a variety of α/Fe ratios throughout their evolution, but they are too distant for detailed analysis of their red giant branch (=RGB, stars that can sample ages >1 Gyr). It is possib ...
Dark matter scaling relations and the assembly epoch of Coma early
... K2000 galaxies are brighter (and have higher stellar mass) than Coma early-types with a similar halo. Can this be an artifact related to differences in the dynamical models? Many of the K2000 models are based on B-band photometry, while we used RC -band images for the Coma galaxies. Elliptical galax ...
... K2000 galaxies are brighter (and have higher stellar mass) than Coma early-types with a similar halo. Can this be an artifact related to differences in the dynamical models? Many of the K2000 models are based on B-band photometry, while we used RC -band images for the Coma galaxies. Elliptical galax ...
Astrophysical X-ray source
Astrophysical X-ray sources are astronomical objects with physical properties which result in the emission of X-rays.There are a number of types of astrophysical objects which emit X-rays, from galaxy clusters, through black holes in active galactic nuclei (AGN) to galactic objects such as supernova remnants, stars, and binary stars containing a white dwarf (cataclysmic variable stars and super soft X-ray sources), neutron star or black hole (X-ray binaries). Some solar system bodies emit X-rays, the most notable being the Moon, although most of the X-ray brightness of the Moon arises from reflected solar X-rays. A combination of many unresolved X-ray sources is thought to produce the observed X-ray background. The X-ray continuum can arise from bremsstrahlung, either magnetic or ordinary Coulomb, black-body radiation, synchrotron radiation, inverse Compton scattering of lower-energy photons be relativistic electrons, knock-on collisions of fast protons with atomic electrons, and atomic recombination, with or without additional electron transitions.Furthermore, celestial entities in space are discussed as celestial X-ray sources. The origin of all observed astronomical X-ray sources is in, near to, or associated with a coronal cloud or gas at coronal cloud temperatures for however long or brief a period.