The Evolution of Protostars - Max-Planck
... Once YSOs are identified, multiple methods are employed to pick out the subset that are protostars still embedded in and presumed to be accreting from surrounding envelopes. For the c2d and Gould Belt clouds, Evans et al. (2009) and Dunham et al. (2013) defined as protostars those objects with at le ...
... Once YSOs are identified, multiple methods are employed to pick out the subset that are protostars still embedded in and presumed to be accreting from surrounding envelopes. For the c2d and Gould Belt clouds, Evans et al. (2009) and Dunham et al. (2013) defined as protostars those objects with at le ...
The distributions and ages of refractory objects in the solar nebula
... lost energy and angular momentum to the gas, spiraling inwards over time (Adachi et al., 1976; Weidenschilling, 1977; Cuzzi and Weidenschilling, 2006). The inward drift velocity of solids was a strong function of the size of the solids being considered, but 0.1–1 cm sized objects, such as the large ...
... lost energy and angular momentum to the gas, spiraling inwards over time (Adachi et al., 1976; Weidenschilling, 1977; Cuzzi and Weidenschilling, 2006). The inward drift velocity of solids was a strong function of the size of the solids being considered, but 0.1–1 cm sized objects, such as the large ...
book_text4
... telescopes to attain a higher resolution and is being vigorously developed by astronomers around the World. Such observations are highly complementary to those made by Hubble since they can exploit the collecting power of much larger telescopes and can be used very effectively to feed such light-hun ...
... telescopes to attain a higher resolution and is being vigorously developed by astronomers around the World. Such observations are highly complementary to those made by Hubble since they can exploit the collecting power of much larger telescopes and can be used very effectively to feed such light-hun ...
Sowing the Seeds of Asymmetry Jet-like Outflows in pPNe and AGB
... by Liu et al. yield masses which are significantly larger than those probed by molecular lines (not surprising as molecular gas expected to survive only in very dense, dusty parts of the PNe). • [CII]158 mm, together with [OI]63 and 146 mm, is a primary coolant of Photodissociation Regions (PDRs). P ...
... by Liu et al. yield masses which are significantly larger than those probed by molecular lines (not surprising as molecular gas expected to survive only in very dense, dusty parts of the PNe). • [CII]158 mm, together with [OI]63 and 146 mm, is a primary coolant of Photodissociation Regions (PDRs). P ...
Confirmation of Hostless Type Ia Supernovae Using Hubble Space
... estimated that . 2% of the stellar mass in dwarf cluster galaxies below detection thresholds. If the SN Ia occurrence rate per unit mass is equivalent in all cluster stellar populations – detected galaxies (∼ 82%), undetected dwarf galaxies (. 2%), and intracluster stars (∼ 16%) – then for MENeaCS w ...
... estimated that . 2% of the stellar mass in dwarf cluster galaxies below detection thresholds. If the SN Ia occurrence rate per unit mass is equivalent in all cluster stellar populations – detected galaxies (∼ 82%), undetected dwarf galaxies (. 2%), and intracluster stars (∼ 16%) – then for MENeaCS w ...
A Herschel/HIFI study of Water in Two Intermediate
... cloud away. Another possibility is that high-mass stars are formed in regions so densely crowded that dense cores begin to merge, with protostars already inside collapsing into one another under their own gravity. While mechanisms that produce high-mass stars have been proposed, their scarcity and ...
... cloud away. Another possibility is that high-mass stars are formed in regions so densely crowded that dense cores begin to merge, with protostars already inside collapsing into one another under their own gravity. While mechanisms that produce high-mass stars have been proposed, their scarcity and ...
T3-Cosmic Star Formation History
... The origin and evolution of galaxies are among the most intriguing and complex chapters in the formation of cosmic structure, and observations in this field have accumulated at an astonishing pace. Multiwavelength imaging surveys with the Hubble (HST) and Spitzer space telescopes and ground-based fac ...
... The origin and evolution of galaxies are among the most intriguing and complex chapters in the formation of cosmic structure, and observations in this field have accumulated at an astonishing pace. Multiwavelength imaging surveys with the Hubble (HST) and Spitzer space telescopes and ground-based fac ...
Kinematics of H $\ mathsf {_2} $ O masers in high
... Main Sequence (ZAMS) stars. This lack of knowledge is a direct consequence of difficulties in observing the earliest evolutionary phases of massive Young Stellar Objects (YSOs), because high-mass stars are rare, form on much shorter timescales (∼105 yr) than those required for low-mass formation, and ...
... Main Sequence (ZAMS) stars. This lack of knowledge is a direct consequence of difficulties in observing the earliest evolutionary phases of massive Young Stellar Objects (YSOs), because high-mass stars are rare, form on much shorter timescales (∼105 yr) than those required for low-mass formation, and ...
Moving mesh cosmology: numerical techniques and global statistics
... 2011), cosmic ray physics (Jubelgas et al. 2008), thermal conduction (Dolag et al. 2004; Jubelgas, Springel & Dolag 2004) or black hole physics (Di Matteo, Springel & Hernquist 2005; Springel et al. 2005a; Di Matteo et al. 2008). Hydrodynamical simulations have been successfully used to study the Ly ...
... 2011), cosmic ray physics (Jubelgas et al. 2008), thermal conduction (Dolag et al. 2004; Jubelgas, Springel & Dolag 2004) or black hole physics (Di Matteo, Springel & Hernquist 2005; Springel et al. 2005a; Di Matteo et al. 2008). Hydrodynamical simulations have been successfully used to study the Ly ...
ASI 2017 Abstract Book - Astronomical Society of India
... galaxy lives influence its evolution? Inevitably, the answers to these questions entail a detailed investigation of all the components of the interstellar medium (gas, dust, metals) and their relation to stellar properties, kinematics and environment. This clearly requires multi-wavelength informati ...
... galaxy lives influence its evolution? Inevitably, the answers to these questions entail a detailed investigation of all the components of the interstellar medium (gas, dust, metals) and their relation to stellar properties, kinematics and environment. This clearly requires multi-wavelength informati ...
Chemical composition of B-type supergiants in the OB8, OB10
... the relevant OB associations. OB78-159 has a radial velocity significantly less than that expected from a star situated in the OB78 association. From WFPC2 images, taken in the U, B, V and I filters, OB78-159 was observed to be part of a multiple system (see Fig. 1; from McCarthy et al. in preparati ...
... the relevant OB associations. OB78-159 has a radial velocity significantly less than that expected from a star situated in the OB78 association. From WFPC2 images, taken in the U, B, V and I filters, OB78-159 was observed to be part of a multiple system (see Fig. 1; from McCarthy et al. in preparati ...
The old globular cluster system of the dIrr galaxy NGC 1427A in the
... this Northern object shares the same general kinematical pattern as the rest of the galaxy body, hence making unlikely its external origin. They also argued that the most likely scenario explaning the morphological features of NGC 1427A is due to its passage through the hot intracluster medium of Fo ...
... this Northern object shares the same general kinematical pattern as the rest of the galaxy body, hence making unlikely its external origin. They also argued that the most likely scenario explaning the morphological features of NGC 1427A is due to its passage through the hot intracluster medium of Fo ...
Decoding Galaxy Evolution with Gas
... guidance that made this dissertation possible. His excellent grasp of the larger picture continually forced me to understand our results in a broader context. His questions cut straight to the heart of the matter and would evoke sheer terror if asked by anyone who does not possess David’s constantly ...
... guidance that made this dissertation possible. His excellent grasp of the larger picture continually forced me to understand our results in a broader context. His questions cut straight to the heart of the matter and would evoke sheer terror if asked by anyone who does not possess David’s constantly ...
Multiwavelength observations of XTE J1118+480`s outburst
... 30% of sources detected by INTEGRAL/IBIS were not known. 80% of Norma sources are X-ray pulsars, high spin periods Spectra typical of neutron stars No radio emission 85% of sources are highly absorbed (X-ray observations): column density NH>1023 cm-2 X-ray absorption >> IR => absorbing matter local ...
... 30% of sources detected by INTEGRAL/IBIS were not known. 80% of Norma sources are X-ray pulsars, high spin periods Spectra typical of neutron stars No radio emission 85% of sources are highly absorbed (X-ray observations): column density NH>1023 cm-2 X-ray absorption >> IR => absorbing matter local ...
New brown dwarfs and giant planets
... - Reid, Hawley & Gizis (1995): PMSU M dwarf survey 4% of the sample would be classed as dark halo by Oppenheimer et al => ~2 x 10^-4 white dwarfs / pc^3 • Most of the Oppenheimer et al. white dwarfs are remnants of the first stars which formed in the thick disk • White dwarfs from the stellar halo a ...
... - Reid, Hawley & Gizis (1995): PMSU M dwarf survey 4% of the sample would be classed as dark halo by Oppenheimer et al => ~2 x 10^-4 white dwarfs / pc^3 • Most of the Oppenheimer et al. white dwarfs are remnants of the first stars which formed in the thick disk • White dwarfs from the stellar halo a ...
THE UV-OPTICAL COLOR MAGNITUDE DIAGRAM. II. PHYSICAL
... is a plausible scenario for bulge-dominated galaxies near the characteristic transition mass under reasonable assumptions regarding quenching timescales. Similarly, we use this technique to estimate the rate of mergers/starbursts that take galaxies off of the star-forming sequence and show that the ...
... is a plausible scenario for bulge-dominated galaxies near the characteristic transition mass under reasonable assumptions regarding quenching timescales. Similarly, we use this technique to estimate the rate of mergers/starbursts that take galaxies off of the star-forming sequence and show that the ...
THE STAR FORMATION AND NUCLEAR ACCRETION HISTORIES OF NORMAL GALAXIES
... may be most abundant at z < ∼ 1 and, if so, they could produce a substantial fraction of the “normal” galaxy X-ray flux at these redshifts. Given their similar evolution, spectral shapes (e.g., Ptak et al. 1999), and potentially similar luminosities, it may be difficult to disentangle the X-ray emis ...
... may be most abundant at z < ∼ 1 and, if so, they could produce a substantial fraction of the “normal” galaxy X-ray flux at these redshifts. Given their similar evolution, spectral shapes (e.g., Ptak et al. 1999), and potentially similar luminosities, it may be difficult to disentangle the X-ray emis ...
X-ray sources in the starburst spiral galaxy M 83
... data now reveal that M 83 has a very highly structured nuclear region (Fig. 2, bottom panel, and Fig. 4). Fifteen discrete sources are detected within a radius of '1600 ('290 pc) from the centre of symmetry of the outer optical isophotes. There are also clump-like features in the predominantly soft ...
... data now reveal that M 83 has a very highly structured nuclear region (Fig. 2, bottom panel, and Fig. 4). Fifteen discrete sources are detected within a radius of '1600 ('290 pc) from the centre of symmetry of the outer optical isophotes. There are also clump-like features in the predominantly soft ...
Variations in Integrated Galactic Initial Mass Functions due to
... makes it hard to infer directly from the masses. Their strong effect on the upper mass limit for the clusters in a galaxy makes it detectable from a statistical point of view, though. See below for a discussion on how Schechter-like CMFs might influence the IGIMF effect. Here we took pure power-laws ...
... makes it hard to infer directly from the masses. Their strong effect on the upper mass limit for the clusters in a galaxy makes it detectable from a statistical point of view, though. See below for a discussion on how Schechter-like CMFs might influence the IGIMF effect. Here we took pure power-laws ...
The old Nuclear Star Cluster in the Milky Way
... hole. For this ∼ 10000 proper motions, ∼ 2500 line-of-sight velocities, and star counts from Fritz et al. (2014) obtained with VLT instruments are used. In addition, for the first time a measurement of dust extinction within the Galactic old nuclear star cluster is presented. As a first step, the su ...
... hole. For this ∼ 10000 proper motions, ∼ 2500 line-of-sight velocities, and star counts from Fritz et al. (2014) obtained with VLT instruments are used. In addition, for the first time a measurement of dust extinction within the Galactic old nuclear star cluster is presented. As a first step, the su ...
SPT 0538−50: PHYSICAL CONDITIONS IN THE ISM OF A STRONGLY... GALAXY AT Z=2.8
... SPT 0538−50 was observed with the Hubble Space Telescope Wide Field Camera 3 on 2011-10-10, as part of program 12659 (PI: Vieira). We use the F110W and F160W filters, the reddest high-throughput filters available. One complete orbit was dedicated to this source, split evenly between the two filters. ...
... SPT 0538−50 was observed with the Hubble Space Telescope Wide Field Camera 3 on 2011-10-10, as part of program 12659 (PI: Vieira). We use the F110W and F160W filters, the reddest high-throughput filters available. One complete orbit was dedicated to this source, split evenly between the two filters. ...
astro-ph/9808039 PDF
... NGC 4449 is surrounded by a neutral hydrogen halo extending to as far as ∼ 1◦ from the visible system, reaching in projection the neighbor galaxy DDO 125, as shown by an Effelsberg 100-meter map (Bajaja, Huchtmeier, & Klein 1994). The corresponding VLA map (Hunter et al. 1998) shows that this gas is ...
... NGC 4449 is surrounded by a neutral hydrogen halo extending to as far as ∼ 1◦ from the visible system, reaching in projection the neighbor galaxy DDO 125, as shown by an Effelsberg 100-meter map (Bajaja, Huchtmeier, & Klein 1994). The corresponding VLA map (Hunter et al. 1998) shows that this gas is ...
Mapping of the extinction in giant molecular clouds using optical star
... masses should appear for a size scale of ∼ 0.5 pc. Obviously, our value corresponds to a limitation of the star counts method with optical data and not to a real characteristic size scale of the cloud. It is therefore natural to extrapolate, down to a minimum mass, the linear part of the relation lo ...
... masses should appear for a size scale of ∼ 0.5 pc. Obviously, our value corresponds to a limitation of the star counts method with optical data and not to a real characteristic size scale of the cloud. It is therefore natural to extrapolate, down to a minimum mass, the linear part of the relation lo ...
spatially resolved star formation history of milky way satellites
... satellites there is another galaxy similar in size than the Milky Way, called Andromeda or Messier 31 (M31), which, as the Milky Way, has its own satellites. These two big galaxies and their own satellites form a self-gravitating association called the Local Group, and hence, the satellite galaxies ...
... satellites there is another galaxy similar in size than the Milky Way, called Andromeda or Messier 31 (M31), which, as the Milky Way, has its own satellites. These two big galaxies and their own satellites form a self-gravitating association called the Local Group, and hence, the satellite galaxies ...