Mass-to-light ratio gradients in early-type galaxy haloes
... have, in the near future, a much better observational picture of the halo mass distributions in a large representative sample of early-type galaxies. To prepare for this observational onslaught, in this paper we want to provide a suite of predictions from the CDM theory for halo mass distributions. ...
... have, in the near future, a much better observational picture of the halo mass distributions in a large representative sample of early-type galaxies. To prepare for this observational onslaught, in this paper we want to provide a suite of predictions from the CDM theory for halo mass distributions. ...
A Test of Pre-Main-Sequence Lithium Depletion Models
... and very little lithium depletion has occurred; much older, and they are on the main sequence, where the HR diagram age is degenerate. We also would like them to be nearby, so we can measure accurate distances and luminosities, and bright, so we can get high S/N spectra. In this paper, we examine li ...
... and very little lithium depletion has occurred; much older, and they are on the main sequence, where the HR diagram age is degenerate. We also would like them to be nearby, so we can measure accurate distances and luminosities, and bright, so we can get high S/N spectra. In this paper, we examine li ...
1987aj 93.1057n the astronomical journal volume 93, number 5 may
... colors obtained above, was subtracted from the 2.2/urn profiles to obtain a profile representative of the central source. For the scans with 0"5-wide slits, the scaled 1.25 ¡urn profile was divided by an additional factor of 2 to account for the 0"5 versus 1"0 width of the slits; here the galaxy cor ...
... colors obtained above, was subtracted from the 2.2/urn profiles to obtain a profile representative of the central source. For the scans with 0"5-wide slits, the scaled 1.25 ¡urn profile was divided by an additional factor of 2 to account for the 0"5 versus 1"0 width of the slits; here the galaxy cor ...
Kinematics of Arp 270: gas flows, nuclear activity
... that there is a powerful source of emission in the central zone of NGC 3396. This leads directly to a possible explanation for the low range of ‘rotational’ velocities detected in this galaxy: they are not in fact rotational, but projected inflow velocities along what appears to be a bar. Since NGC ...
... that there is a powerful source of emission in the central zone of NGC 3396. This leads directly to a possible explanation for the low range of ‘rotational’ velocities detected in this galaxy: they are not in fact rotational, but projected inflow velocities along what appears to be a bar. Since NGC ...
A New Model without Dark Matter for the Rotation of Spiral Galaxies
... NGC 5128 (Cen A) and IC 4296. A literature search shows that at least another 11 sources have extended radio-structures indicative of a collimated outflow, although in several cases this can only be seen in high resolution VLBI images, such as the mass scale double-lobes in UGC 7760 or the one-sided ...
... NGC 5128 (Cen A) and IC 4296. A literature search shows that at least another 11 sources have extended radio-structures indicative of a collimated outflow, although in several cases this can only be seen in high resolution VLBI images, such as the mass scale double-lobes in UGC 7760 or the one-sided ...
The white dwarf binary pathways survey – I. A sample of FGK stars
... SN Ia spectra (Branch et al. 1995). Moreover, there is both theoretical and observational evidence for a large population of close double white dwarf binaries (Yungelson et al. 1994; Nelemans & Tout 2005; Napiwotzki et al. 2001). However, there is some uncertainty as to whether the merger leads to a ...
... SN Ia spectra (Branch et al. 1995). Moreover, there is both theoretical and observational evidence for a large population of close double white dwarf binaries (Yungelson et al. 1994; Nelemans & Tout 2005; Napiwotzki et al. 2001). However, there is some uncertainty as to whether the merger leads to a ...
Core-Halo Age Gradients and Star Formation in the Orion Nebula
... method relies on evolutionary models, it does not provide “absolute” ages, as with most the standard PMS age methods. In this work, a similar approach is applied to the stars within the NGC 2024 and ONC clusters. Calculating median ages and their confidence intervals for different subregions of inte ...
... method relies on evolutionary models, it does not provide “absolute” ages, as with most the standard PMS age methods. In this work, a similar approach is applied to the stars within the NGC 2024 and ONC clusters. Calculating median ages and their confidence intervals for different subregions of inte ...
arXiv:1604.01613v2 [astro-ph.SR] 23 Aug 2016
... SN Ia spectra (Branch et al. 1995). Moreover, there is both theoretical and observational evidence for a large population of close double white dwarf binaries (Yungelson et al. 1994; Nelemans & Tout 2005; Napiwotzki et al. 2001). However, there is some uncertainty as to whether the merger leads to a ...
... SN Ia spectra (Branch et al. 1995). Moreover, there is both theoretical and observational evidence for a large population of close double white dwarf binaries (Yungelson et al. 1994; Nelemans & Tout 2005; Napiwotzki et al. 2001). However, there is some uncertainty as to whether the merger leads to a ...
The redMaPPer Galaxy Cluster Catalog From DES Science
... view, for a total of ∼ 32 deg2 of deeper imaging (including extra offset pointings of SN fields taken during SV). Finally, there are smaller discontinguous regions targeting massive clusters (Melchior et al. 2015) and the COSMOS field (Scoville et al. 2007). We utilize this DES SV data set to constr ...
... view, for a total of ∼ 32 deg2 of deeper imaging (including extra offset pointings of SN fields taken during SV). Finally, there are smaller discontinguous regions targeting massive clusters (Melchior et al. 2015) and the COSMOS field (Scoville et al. 2007). We utilize this DES SV data set to constr ...
Massive Star Formation in the Galactic Center
... molecular material from further out in the Galaxy powers continuous and robust star formation activity in the region. It is still unclear how magnetic field strength affects star formation. If it does matter, then the GC might be expected to reveal such effects. The strength of the magnetic field in the ...
... molecular material from further out in the Galaxy powers continuous and robust star formation activity in the region. It is still unclear how magnetic field strength affects star formation. If it does matter, then the GC might be expected to reveal such effects. The strength of the magnetic field in the ...
Rigorous treatment of barycentric stellar motion
... by Eisner (1967) the rigorous propagation was derived as a series expansion in t and v/c, though in a form not very useful for practical application. The author concluded that the light-time effect “can be neglected in astrometry of present-day precision, though not necessarily if measurement outside ...
... by Eisner (1967) the rigorous propagation was derived as a series expansion in t and v/c, though in a form not very useful for practical application. The author concluded that the light-time effect “can be neglected in astrometry of present-day precision, though not necessarily if measurement outside ...
Collisions and close encounters involving massive main
... (2002) have studied encounters between low-mass main-sequence stars and, with the exception of Benz & Hills (1987), found that mixing was minimal. It is important to determine if this is also the case in encounters involving high-mass stars, since the merger may deliver fresh hydrogen to the core of ...
... (2002) have studied encounters between low-mass main-sequence stars and, with the exception of Benz & Hills (1987), found that mixing was minimal. It is important to determine if this is also the case in encounters involving high-mass stars, since the merger may deliver fresh hydrogen to the core of ...
LACEwING: A New Moving Group Analysis Code
... The groups have ages between ∼5 Myr old (ò Cha) and 600–800 Myr old (Hyades). The fundamental assumption about these NYMGs and open clusters is that they are the products of single bursts of star formation. This means that every constituent member should be roughly the same age (with attendant const ...
... The groups have ages between ∼5 Myr old (ò Cha) and 600–800 Myr old (Hyades). The fundamental assumption about these NYMGs and open clusters is that they are the products of single bursts of star formation. This means that every constituent member should be roughly the same age (with attendant const ...
Modelling galaxy spectra in presence of interstellar dust – II. From
... (SWIRE – Lonsdale et al. 2003) and the SIRTF Nearby Galaxies Survey (SINGS – Kennicutt et al. 2003). The IR data will increase even more with the coming ASTRO-F mission (Pearson et al. 2004) and the advent of the James Webb Space Telescope (JWST). Combined with other astronomical data bases, they pr ...
... (SWIRE – Lonsdale et al. 2003) and the SIRTF Nearby Galaxies Survey (SINGS – Kennicutt et al. 2003). The IR data will increase even more with the coming ASTRO-F mission (Pearson et al. 2004) and the advent of the James Webb Space Telescope (JWST). Combined with other astronomical data bases, they pr ...
The enigmatic pair of dwarf galaxies Leo IV and Leo V: coincidence
... larger than indicated by previous measurements based on shallower data. With a half-light radius of rh =4.′ 6±0.′ 8 (206±36 pc) and rh =2.′ 6±0.′6 (133±31 pc), respectively, both systems are now well within the physical size bracket of typical dwarf spheroidal Milky Way satellites. Both are also fou ...
... larger than indicated by previous measurements based on shallower data. With a half-light radius of rh =4.′ 6±0.′ 8 (206±36 pc) and rh =2.′ 6±0.′6 (133±31 pc), respectively, both systems are now well within the physical size bracket of typical dwarf spheroidal Milky Way satellites. Both are also fou ...
ppt - RESCEU
... & maintain the primordial sponge topology at all redshifts! (= the original idea of using topology for the test for the Gaussianity of the primordial density field by Gott et al. in 1986) ...
... & maintain the primordial sponge topology at all redshifts! (= the original idea of using topology for the test for the Gaussianity of the primordial density field by Gott et al. in 1986) ...
Hunting for Substructure in the Milky Way
... Studies of the Milky Way including how it formed and evolved through time are the key to understanding how other galaxies behave. The Milky Way is the most convenient galaxy to study, because the close proximity of stars means astronomers can collect precise spectral and dynamical data from individu ...
... Studies of the Milky Way including how it formed and evolved through time are the key to understanding how other galaxies behave. The Milky Way is the most convenient galaxy to study, because the close proximity of stars means astronomers can collect precise spectral and dynamical data from individu ...
S282_2 Introduction to active galaxies
... Why would the atoms be in motion? An obvious reason is that they are ‘hot’. Atoms in a hot gas, for example, will be moving randomly with a range of speeds related to the temperature of the gas. For a gas of atoms of mass m at a temperature T, the velocity dispersion is given by ...
... Why would the atoms be in motion? An obvious reason is that they are ‘hot’. Atoms in a hot gas, for example, will be moving randomly with a range of speeds related to the temperature of the gas. For a gas of atoms of mass m at a temperature T, the velocity dispersion is given by ...
1 Globular Cluster Systems - McMaster Physics and Astronomy
... used by Shapley to estimate the centroid of the system and thus { again for the rst time { to determine the distance from the Sun to the Galactic center. The second graph shows us exactly the same plot with the most modern measurements. The data have improved dramatically over the intervening 80 ye ...
... used by Shapley to estimate the centroid of the system and thus { again for the rst time { to determine the distance from the Sun to the Galactic center. The second graph shows us exactly the same plot with the most modern measurements. The data have improved dramatically over the intervening 80 ye ...
A Simple Model for r-Process Scatter and Halo Evolution
... ent universality of the r-process, one might expect that all ratios among r-process nuclides to always be constant (with pollution by the s-process increasing with [Fe/H]). This leads to the prediction that at the lowest metallicities, when the s-process has not turned on, ratios among r-process ele ...
... ent universality of the r-process, one might expect that all ratios among r-process nuclides to always be constant (with pollution by the s-process increasing with [Fe/H]). This leads to the prediction that at the lowest metallicities, when the s-process has not turned on, ratios among r-process ele ...
Magnitude-range brightness variations of overactive K giants
... DM UMa (BD +61◦ 1211, HIP 53425) is also a single-lined RS CVn binary (K0-1 IV-III, Prot≈orb =7.49 days) at a distance of 139 pc (van Leeuwen 2007). The star has a 28-year photometric dataset collected from the literature together with a long series of new observations taken between 1988-2009, all p ...
... DM UMa (BD +61◦ 1211, HIP 53425) is also a single-lined RS CVn binary (K0-1 IV-III, Prot≈orb =7.49 days) at a distance of 139 pc (van Leeuwen 2007). The star has a 28-year photometric dataset collected from the literature together with a long series of new observations taken between 1988-2009, all p ...
The Hamburg/ESO R-process Enhanced Star survey (HERES)
... Th/Eu ratio of log (Th/Eu) = −0.10 is even higher than the ratio observed in CS 31081−001. Unfortunately the Subaru/HDS spectrum of the r-II star CS 22183−031 available to Honda et al. was not of sufficient quality to detect Th. Since the discovery of CS 22892−052, and the realization of the potential ...
... Th/Eu ratio of log (Th/Eu) = −0.10 is even higher than the ratio observed in CS 31081−001. Unfortunately the Subaru/HDS spectrum of the r-II star CS 22183−031 available to Honda et al. was not of sufficient quality to detect Th. Since the discovery of CS 22892−052, and the realization of the potential ...
Astronomy Astrophysics
... Th/Eu ratio of log (Th/Eu) = −0.10 is even higher than the ratio observed in CS 31081−001. Unfortunately the Subaru/HDS spectrum of the r-II star CS 22183−031 available to Honda et al. was not of sufficient quality to detect Th. Since the discovery of CS 22892−052, and the realization of the potential ...
... Th/Eu ratio of log (Th/Eu) = −0.10 is even higher than the ratio observed in CS 31081−001. Unfortunately the Subaru/HDS spectrum of the r-II star CS 22183−031 available to Honda et al. was not of sufficient quality to detect Th. Since the discovery of CS 22892−052, and the realization of the potential ...
The effect of starspots on the radii of low-mass
... the young Pleiades cluster. We find that PMS stars are more inflated for a given level of spot coverage than ZAMS stars of a similar luminosity and that the spot coverage required to produce the measured radii is large but perhaps not excessive. Finally it is shown that, in contrast to models that s ...
... the young Pleiades cluster. We find that PMS stars are more inflated for a given level of spot coverage than ZAMS stars of a similar luminosity and that the spot coverage required to produce the measured radii is large but perhaps not excessive. Finally it is shown that, in contrast to models that s ...
Cosmic distance ladder
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A real direct distance measurement of an astronomical object is possible only for those objects that are ""close enough"" (within about a thousand parsecs) to Earth. The techniques for determining distances to more distant objects are all based on various measured correlations between methods that work at close distances and methods that work at larger distances. Several methods rely on a standard candle, which is an astronomical object that has a known luminosity.The ladder analogy arises because no one technique can measure distances at all ranges encountered in astronomy. Instead, one method can be used to measure nearby distances, a second can be used to measure nearby to intermediate distances, and so on. Each rung of the ladder provides information that can be used to determine the distances at the next higher rung.