Properties of Galactic B supergiants
... the mean nebular and stellar CMFGEN results. For the post-RSG stage after 5.2 Myr, [N/O] = +1.8 dex is predicted. Consequently, Sher 25 is consistent with a single star evolving towards the RSG phase. However, amongst the most successful models to explain SN 1987A during its B supergiant phase are t ...
... the mean nebular and stellar CMFGEN results. For the post-RSG stage after 5.2 Myr, [N/O] = +1.8 dex is predicted. Consequently, Sher 25 is consistent with a single star evolving towards the RSG phase. However, amongst the most successful models to explain SN 1987A during its B supergiant phase are t ...
FIELD ASTRONOMY
... The solar day, or the time corresponding to one rotation of the earth with respect to the direction of the sun, is the most natural unit of time for ordinary purposes. If time was regulated by stars, sidereal noon would occur at night during half the year. For obvious reasons, this would not be a sa ...
... The solar day, or the time corresponding to one rotation of the earth with respect to the direction of the sun, is the most natural unit of time for ordinary purposes. If time was regulated by stars, sidereal noon would occur at night during half the year. For obvious reasons, this would not be a sa ...
HI in Early-type Galaxies
... galaxies is quite large, but it appears that there are a few systematic trends in the data, and in particular that some of the HI properties may be connected to properties observed at other wavebands. Many low-luminosity early-type galaxies that have HI, have this HI in a regularly rotating disk. In ...
... galaxies is quite large, but it appears that there are a few systematic trends in the data, and in particular that some of the HI properties may be connected to properties observed at other wavebands. Many low-luminosity early-type galaxies that have HI, have this HI in a regularly rotating disk. In ...
ABSTRACT Exoplanet Habitability and an Analysis of Gliese 436 b
... and nitrogen with nitrogen most likely being the most important of the three due to its presence in DNA and proteins.11 Remember that without the presence of water though, these building blocks will not lead to the development of life. Along with water and these building blocks, UV radiation and gre ...
... and nitrogen with nitrogen most likely being the most important of the three due to its presence in DNA and proteins.11 Remember that without the presence of water though, these building blocks will not lead to the development of life. Along with water and these building blocks, UV radiation and gre ...
Y.Ueda_Future_HE_Mission2006 - X
... In the local universe the number density of Compton thick AGNs may be comparable to or even larger than Compton thin AGNs (Maiolino et al. 2003) ...
... In the local universe the number density of Compton thick AGNs may be comparable to or even larger than Compton thin AGNs (Maiolino et al. 2003) ...
Development of Iodine Cells for the Subaru HDS and the Okayama
... errors. Thus, we have developed a new method to reconstruct a pure stellar spectrum from star + I2 spectra. Details of this method are described in subsection 2.2. For modeling the IP, we adopt a technique described by Valenti et al. (1995). The IP is modeled with a combination of a central and seve ...
... errors. Thus, we have developed a new method to reconstruct a pure stellar spectrum from star + I2 spectra. Details of this method are described in subsection 2.2. For modeling the IP, we adopt a technique described by Valenti et al. (1995). The IP is modeled with a combination of a central and seve ...
Sublimation temperature of circumstellar dust particles and its importance Hiroshi Kobayashi
... P-R drag from stellar radiation, the P-R drag due to the stellar wind also transports the particles. However, the magnitude of pile-up, its location, and sublimation temperature hardly depend on which drag determines their transport (Kobayashi et al., 2008, 2009). A particle generated in a dust sour ...
... P-R drag from stellar radiation, the P-R drag due to the stellar wind also transports the particles. However, the magnitude of pile-up, its location, and sublimation temperature hardly depend on which drag determines their transport (Kobayashi et al., 2008, 2009). A particle generated in a dust sour ...
Lecture 3
... Other Galaxies at z=3 • Lyman Break Galaxies are selected to be UVbright Strongly star forming Not too much dust extinction • They can’t account for all the material at z=3, so other techniques must fill in the gaps: – DLAs – Narrow Band Surveys – Sub-millimeter or Infrared selection ...
... Other Galaxies at z=3 • Lyman Break Galaxies are selected to be UVbright Strongly star forming Not too much dust extinction • They can’t account for all the material at z=3, so other techniques must fill in the gaps: – DLAs – Narrow Band Surveys – Sub-millimeter or Infrared selection ...
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 ...
LIGO SURF 2006 Lecture 1 - Indico
... Gravitational Wave Astronomy (observation, populations, properties of the most energetic processes in the universe): ...
... Gravitational Wave Astronomy (observation, populations, properties of the most energetic processes in the universe): ...
On the composition of GRBs` Collapsar jets
... larger tail towards lower energies than towards higher energies. Taking a typical LGRB duration of ∼30 s this energy corresponds to a typical one-sided jet luminosity of Lj ∼ 2 × 1049 erg s−1 . Guetta, Piran & Waxman (2005) found similar values of typical jet luminosity and opening angle. Estimates ...
... larger tail towards lower energies than towards higher energies. Taking a typical LGRB duration of ∼30 s this energy corresponds to a typical one-sided jet luminosity of Lj ∼ 2 × 1049 erg s−1 . Guetta, Piran & Waxman (2005) found similar values of typical jet luminosity and opening angle. Estimates ...
White Paper on Nuclear Astrophysics
... This white paper should also inform the nuclear physics community and funding agencies about the scientific directions and priorities of the field with the goal of providing input for the 2014 Long Range Plan. The answer of many questions in nuclear astrophysics can be found in the physics of nuclea ...
... This white paper should also inform the nuclear physics community and funding agencies about the scientific directions and priorities of the field with the goal of providing input for the 2014 Long Range Plan. The answer of many questions in nuclear astrophysics can be found in the physics of nuclea ...
An X-Ray, Optical and Infra-red study of High-Mass X
... First and foremost I would like to thank my supervisor, Malcolm Coe, for his continued guidance and support. His drive to obtain and exploit all manner of data has given me a wealth of information on which to base my thesis and sent me to some of the world’s most incredible places in the process. I ...
... First and foremost I would like to thank my supervisor, Malcolm Coe, for his continued guidance and support. His drive to obtain and exploit all manner of data has given me a wealth of information on which to base my thesis and sent me to some of the world’s most incredible places in the process. I ...
observations of white dwarfs in the solar neighborhood
... range. The 100 slit gave 3.2 Å spectral resolution (FWHM). The main observing program was focused on accurate radial velocities, and the procedures used gave stability better than 10 km s1. When observing at substantial air masses, we rotated the slit to the parallactic angle, avoiding atmospheri ...
... range. The 100 slit gave 3.2 Å spectral resolution (FWHM). The main observing program was focused on accurate radial velocities, and the procedures used gave stability better than 10 km s1. When observing at substantial air masses, we rotated the slit to the parallactic angle, avoiding atmospheri ...
Astronomy Astrophysics Gaia-ESO Survey: The analysis of high-resolution The
... Context. The ongoing Gaia-ESO Public Spectroscopic Survey is using FLAMES at the VLT to obtain high-quality medium-resolution Giraffe spectra for about 105 stars and high-resolution UVES spectra for about 5000 stars. With UVES, the Survey has already observed 1447 FGK-type stars. Aims. These UVES spe ...
... Context. The ongoing Gaia-ESO Public Spectroscopic Survey is using FLAMES at the VLT to obtain high-quality medium-resolution Giraffe spectra for about 105 stars and high-resolution UVES spectra for about 5000 stars. With UVES, the Survey has already observed 1447 FGK-type stars. Aims. These UVES spe ...
The Westerbork Hydrogen Accretion in LOcal GAlaxieS \(HALOGAS
... Halo gas is also present in at least one low surface brightness (LSB) galaxy (NGC 4395) with very little ongoing star formation, and a 107 M gas cloud in that system is likely in the process of being accreted (Heald & Oosterloo 2008). Moreover, evidence suggests the presence of a neutral gas halo i ...
... Halo gas is also present in at least one low surface brightness (LSB) galaxy (NGC 4395) with very little ongoing star formation, and a 107 M gas cloud in that system is likely in the process of being accreted (Heald & Oosterloo 2008). Moreover, evidence suggests the presence of a neutral gas halo i ...
White dwarfs, black holes and neutron stars in close binaries
... object, called a white dwarf (e.g. S ALPETER 1971). It has a very high density: it has a size comparable to the size of the Earth but a mass similar to that of the Sun (see Fig. 1.1). For a short while the expelled hydrogen envelope is ionised by the intense radiation of the hot core, and can be obs ...
... object, called a white dwarf (e.g. S ALPETER 1971). It has a very high density: it has a size comparable to the size of the Earth but a mass similar to that of the Sun (see Fig. 1.1). For a short while the expelled hydrogen envelope is ionised by the intense radiation of the hot core, and can be obs ...
maximum likelihood fitting of tidal streams with application
... star counts often suggested a more spherical spheroid (Bahcall 1986). By early in the 21st century, the spheroid was still thought of as a smooth power-law distribution, but studies were starting to show that the shape of the spheroid depended on the type of star being observed, and it was noted tha ...
... star counts often suggested a more spherical spheroid (Bahcall 1986). By early in the 21st century, the spheroid was still thought of as a smooth power-law distribution, but studies were starting to show that the shape of the spheroid depended on the type of star being observed, and it was noted tha ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.