Formation of the First Galaxies: Theory and Simulations
... Fig. 3 The properties of the primordial gas inside a first star-forming minihalo at z = 23 (left panel) and a first galaxy-hosting halo at z = 10 (right panel), as found in a cosmological hydrodynamics simulation. The temperature, electron fraction, HD fraction, and H2 fraction are shown as functio ...
... Fig. 3 The properties of the primordial gas inside a first star-forming minihalo at z = 23 (left panel) and a first galaxy-hosting halo at z = 10 (right panel), as found in a cosmological hydrodynamics simulation. The temperature, electron fraction, HD fraction, and H2 fraction are shown as functio ...
A very massive runaway star from Cygnus OB2⋆
... v∗ is the spatial velocity of the star. The distance given in Eq. (5) assumes that the bow shock is bound by shock fronts on both sides. In reality, the non-zero cooling time of the shocked stellar wind builds up a thick layer of low-density, high-temperature gas between the reverse shock on the ste ...
... v∗ is the spatial velocity of the star. The distance given in Eq. (5) assumes that the bow shock is bound by shock fronts on both sides. In reality, the non-zero cooling time of the shocked stellar wind builds up a thick layer of low-density, high-temperature gas between the reverse shock on the ste ...
The Extragalactic Group of MPE and USM
... of Massive Galaxies in the FORS Deep and GOODS South fields • Study evolution of galaxies with broadband deep U to K surveys. • LFs, Mass Functions, SFRs do not require spectroscopy but can be derived with accurate photometric redshifts. • Advantage of photo z: no color selection bias, fainter lumin ...
... of Massive Galaxies in the FORS Deep and GOODS South fields • Study evolution of galaxies with broadband deep U to K surveys. • LFs, Mass Functions, SFRs do not require spectroscopy but can be derived with accurate photometric redshifts. • Advantage of photo z: no color selection bias, fainter lumin ...
Deep Chandra Observations of the Arches and Quintuplet Clusters at... Hui Dong Q. Daniel Wang ( &
... bright point-like sources that are clearly associated with the clusters. Some of the sources are positionally coincident with known radio sources with strong stellar winds. The sources have similar X-ray spectra, which are dominantly thermal and show an unusually strong 6.7 keV emission line, indica ...
... bright point-like sources that are clearly associated with the clusters. Some of the sources are positionally coincident with known radio sources with strong stellar winds. The sources have similar X-ray spectra, which are dominantly thermal and show an unusually strong 6.7 keV emission line, indica ...
1987aj 93.1057n the astronomical journal volume 93, number 5 may
... evidence for the presence of such a nucleus in Arp 220. More recently, DePoy ( 1987), for example, has measured a width of 1200 km s_ 1 for the Brackett alpha line, again indicative of an active galactic nucleus. Evidence for starburst activity comes, for example, from Sanders et al (1986) and Scovi ...
... evidence for the presence of such a nucleus in Arp 220. More recently, DePoy ( 1987), for example, has measured a width of 1200 km s_ 1 for the Brackett alpha line, again indicative of an active galactic nucleus. Evidence for starburst activity comes, for example, from Sanders et al (1986) and Scovi ...
Dennett-Thorpe-deBruyn,2002
... The determination of a peculiar velocity argues that the scattering structure is discrete. This measurement of the transverse velocity of the ionised scattering material cannot be directly compared to radial velocity measurements of HI, but we note that there is no anomalous feature known in this d ...
... The determination of a peculiar velocity argues that the scattering structure is discrete. This measurement of the transverse velocity of the ionised scattering material cannot be directly compared to radial velocity measurements of HI, but we note that there is no anomalous feature known in this d ...
Gas lines from the 5-Myr old optically thin disk around HD141569A
... distribution (SED) and images of disks. Sophisticated and reliable radiative-transfer codes are available (e.g., Pinte et al. 2006, 2009; Min et al. 2009; Dullemond & Dominik 2004). The accuracy of the dust mass estimates is limited by the uncertainties in the opacities due to our limited knowledge ...
... distribution (SED) and images of disks. Sophisticated and reliable radiative-transfer codes are available (e.g., Pinte et al. 2006, 2009; Min et al. 2009; Dullemond & Dominik 2004). The accuracy of the dust mass estimates is limited by the uncertainties in the opacities due to our limited knowledge ...
Millisecond Pulsar Binaries at Transition
... Further Speculation Roughly 200 LMXBs are identified, most of them are ...
... Further Speculation Roughly 200 LMXBs are identified, most of them are ...
103-122
... 2. LB's result show [α/Fe] to increase slightly in the extreme halo stars ([Fe/H] < –2) (Fig. 5). An assumption that the intrinsic scatter in [α /Fe] for halo stars is small is not necessarily compatible with the theories of Galactic chemical evolution. If the αelements and the iron-group are synthe ...
... 2. LB's result show [α/Fe] to increase slightly in the extreme halo stars ([Fe/H] < –2) (Fig. 5). An assumption that the intrinsic scatter in [α /Fe] for halo stars is small is not necessarily compatible with the theories of Galactic chemical evolution. If the αelements and the iron-group are synthe ...
Global structure and kinematics of stellar haloes in cosmological
... Mpc in radius) extracted from the Millennium Simulation (Springel et al. 2005). The regions were picked to have overdensities at z = 1.5 of (+2, +1, 0, −1, −2)σ, where σ is the root-mean-square deviation from the mean on this spatial scale. The 5 spheres are therefore environmentally diverse in term ...
... Mpc in radius) extracted from the Millennium Simulation (Springel et al. 2005). The regions were picked to have overdensities at z = 1.5 of (+2, +1, 0, −1, −2)σ, where σ is the root-mean-square deviation from the mean on this spatial scale. The 5 spheres are therefore environmentally diverse in term ...
Gravitationally lensed galaxies at 2 z 3.5: direct abundance
... narrow emission lines from the C IV λλ1548, 1550 doublet shown in Fig. 1. C IV λλ1548, 1550 are almost always seen in absorption in high-redshift galaxies (another exception is the Lynx arc in Holden et al. 2001; Fosbury et al. 2003), or in P Cygni profiles with a minor contribution from the emissio ...
... narrow emission lines from the C IV λλ1548, 1550 doublet shown in Fig. 1. C IV λλ1548, 1550 are almost always seen in absorption in high-redshift galaxies (another exception is the Lynx arc in Holden et al. 2001; Fosbury et al. 2003), or in P Cygni profiles with a minor contribution from the emissio ...
z= 1000 - z= 10
... Identify and measure >500 clusters in an unbiased survey with multi-wavelength observations ...
... Identify and measure >500 clusters in an unbiased survey with multi-wavelength observations ...
L7 Protoplanetary disks Part III
... solution has the same form as the steady state solution without a central couple: Thus, we assume that if we now want to include the central couple with the star, we can replace this expression with the one for the steady state with central couple, leaving the rest unchanged. For a physically usable ...
... solution has the same form as the steady state solution without a central couple: Thus, we assume that if we now want to include the central couple with the star, we can replace this expression with the one for the steady state with central couple, leaving the rest unchanged. For a physically usable ...
The Formation of Primordial Luminous Objects - SLAC
... they are believed to interact only through gravity, they freely propagate from overdense to underdense regions, wiping out the density perturbations. However, at any given cosmic time t, this will affect only wavelengths smaller than the free streaming length, i.e. the proper distance lFS (t) which ...
... they are believed to interact only through gravity, they freely propagate from overdense to underdense regions, wiping out the density perturbations. However, at any given cosmic time t, this will affect only wavelengths smaller than the free streaming length, i.e. the proper distance lFS (t) which ...
Discovery of a Dwarf Poststarburst Galaxy near a High Column
... We report the discovery of a dwarf (MB = 13.9) poststarburst galaxy coincident in recession velocity (within uncertainties) with the highest column density absorber (NH i = 1015.85 cm2 at cz ¼ 1586 km s 1) in the 3C 273 sight line. This galaxy is by far the closest galaxy to this absorber, projec ...
... We report the discovery of a dwarf (MB = 13.9) poststarburst galaxy coincident in recession velocity (within uncertainties) with the highest column density absorber (NH i = 1015.85 cm2 at cz ¼ 1586 km s 1) in the 3C 273 sight line. This galaxy is by far the closest galaxy to this absorber, projec ...
The Formation of Systems with Tightly
... Figure 1 shows the r-vr path of a solid of a single size s. The tracks are consistent with the classic Weidenschilling (1977) results. The shape of each curve reflects the different drag regimes. Abrupt kinks for the 10 m solid are due to the piecewise Reynolds drag solution. While a smoother transi ...
... Figure 1 shows the r-vr path of a solid of a single size s. The tracks are consistent with the classic Weidenschilling (1977) results. The shape of each curve reflects the different drag regimes. Abrupt kinks for the 10 m solid are due to the piecewise Reynolds drag solution. While a smoother transi ...
white dwarfs and the age of the universe
... source) and it would be observationally impossible to distinguish between both possibilities. However, the importance of such a source strongly depends on the mass, MH , of the hydrogen layer. If MH ≤ 10−4 M⊙ , the pp contribution quickly drops and never becomes dominant. Since astero-seismological ...
... source) and it would be observationally impossible to distinguish between both possibilities. However, the importance of such a source strongly depends on the mass, MH , of the hydrogen layer. If MH ≤ 10−4 M⊙ , the pp contribution quickly drops and never becomes dominant. Since astero-seismological ...
The Stellar Population Synthesis Technique Charlie Conroy Princeton
... The timescale for molecular cloud (MC) disruption, tesc, is not wellconstrained observationally Plausibly ranges from 106.5 < tesc < 107.5 yrs – Will depend on metallicity, intensity of UV radiation (e.g. local SFR), etc. ...
... The timescale for molecular cloud (MC) disruption, tesc, is not wellconstrained observationally Plausibly ranges from 106.5 < tesc < 107.5 yrs – Will depend on metallicity, intensity of UV radiation (e.g. local SFR), etc. ...
WIMPs and MACHOs - Caltech Astronomy
... except by exquisitely sensitive equipment. These difficulties, however, have not stopped many groups throughout the world from developing devices capable of detecting WIMPs. The detection rates turn out to be within and just beyond the reach of current experimental efforts. The basic idea is to dete ...
... except by exquisitely sensitive equipment. These difficulties, however, have not stopped many groups throughout the world from developing devices capable of detecting WIMPs. The detection rates turn out to be within and just beyond the reach of current experimental efforts. The basic idea is to dete ...
Spiral Galaxies: Origin by Gravitational Vectors Merging Theory
... The first position next to the centre will get a stronger gravitational force towards the gravitation centre than the middle or the distant position. That's the consequence of Newton's gravitation law. Those three positions will get different acceleration towards the gravitation centre although inte ...
... The first position next to the centre will get a stronger gravitational force towards the gravitation centre than the middle or the distant position. That's the consequence of Newton's gravitation law. Those three positions will get different acceleration towards the gravitation centre although inte ...
VV Cephei Eclipse Campaign 2017/19
... A Lhires III or equivalent spectrograph with a 2400 line/mm grating is suggested for the high-resolution work. The star system’s optical spectrum is characterized by strong Balmer and Fe II emission lines. Out-of-eclipse VV Cephei displays dual large hydrogen alpha emission lines that disappear duri ...
... A Lhires III or equivalent spectrograph with a 2400 line/mm grating is suggested for the high-resolution work. The star system’s optical spectrum is characterized by strong Balmer and Fe II emission lines. Out-of-eclipse VV Cephei displays dual large hydrogen alpha emission lines that disappear duri ...
Properties of simulated Milky Way-mass galaxies in loose group and
... dispersion-age relations of galaxies in the different environments. Loose group galaxies appear to have more discrete steps in their velocity dispersion-age relations, if this is true it suggests that impulsive heating is more efficient in the stars of galaxies in denser environment than in the field. ...
... dispersion-age relations of galaxies in the different environments. Loose group galaxies appear to have more discrete steps in their velocity dispersion-age relations, if this is true it suggests that impulsive heating is more efficient in the stars of galaxies in denser environment than in the field. ...
Sensing the Radio Sky
... emit more radiation than the periphery, or edges, where there are fewer magnetic fields for particles to spiral around. The brighter areas shown in the STARLAB generally have more intense magnetic fields and therefore trap more particles, giving off more intense radiation. Likewise, at the dim edges ...
... emit more radiation than the periphery, or edges, where there are fewer magnetic fields for particles to spiral around. The brighter areas shown in the STARLAB generally have more intense magnetic fields and therefore trap more particles, giving off more intense radiation. Likewise, at the dim edges ...
our knowledge of high-mass star formation at the dawn of - CEA-Irfu
... partners. Non-equal mass encounters, circumstellar disks, and binary components could decrease this number to about 106 pc−3 , but such stellar density is highly unlikely to be the general case of high-mass star-forming sites. ...
... partners. Non-equal mass encounters, circumstellar disks, and binary components could decrease this number to about 106 pc−3 , but such stellar density is highly unlikely to be the general case of high-mass star-forming sites. ...
Are Gamma-Ray Bursts good Star Formation Indicators?
... populations of galaxies in proportion to the contribution of each population to the overall star formation rate (eg. Trentham et al. 2002 MNRAS). Generally the GRB hosts are small, blue (in optical/nIR colours) galaxies in the redshift range 0.5
... populations of galaxies in proportion to the contribution of each population to the overall star formation rate (eg. Trentham et al. 2002 MNRAS). Generally the GRB hosts are small, blue (in optical/nIR colours) galaxies in the redshift range 0.5