Comparison between the luminosity functions of X
... of their optical classification and thus there is good agreement between the X-ray and optical type-1 classification. The total luminosity function is described by a double power-law form with a break luminosity of L(3−20 keV) ≈ 4×1043 erg s−1 . Shinozaki et al. (2006) have derived the luminosity fu ...
... of their optical classification and thus there is good agreement between the X-ray and optical type-1 classification. The total luminosity function is described by a double power-law form with a break luminosity of L(3−20 keV) ≈ 4×1043 erg s−1 . Shinozaki et al. (2006) have derived the luminosity fu ...
A HUBBLE DIAGRAM FROM TYPE II SUPERNOVAE BASED
... of spectral information. We use a data set from the Carnegie Supernovae Project I for which optical and nearinfrared lightcurves were obtained. The apparent magnitude is corrected by two observables, one corresponding to the slope of the plateau in the V band and the second a color term. We obtain ...
... of spectral information. We use a data set from the Carnegie Supernovae Project I for which optical and nearinfrared lightcurves were obtained. The apparent magnitude is corrected by two observables, one corresponding to the slope of the plateau in the V band and the second a color term. We obtain ...
the article as PDF - Project VS
... 2) a quadratic least square fitting, which uses the average period value over the elapsed time interval (P): ...
... 2) a quadratic least square fitting, which uses the average period value over the elapsed time interval (P): ...
Niraj D. Welikala Thesis - D-Scholarship@Pitt
... The spectrum of fluctuations is roughly flat on scales greater than 100 Megaparsecs (Mpc)1 and on these scales the density fluctuations are small in size (rms fluctuations of the order ∼ 0.1 at 1 Gpc). However, on scales of the order of 10 Mpc, the density fluctuations are large (∼ 1). The most app ...
... The spectrum of fluctuations is roughly flat on scales greater than 100 Megaparsecs (Mpc)1 and on these scales the density fluctuations are small in size (rms fluctuations of the order ∼ 0.1 at 1 Gpc). However, on scales of the order of 10 Mpc, the density fluctuations are large (∼ 1). The most app ...
Dust attenuation up to z ≃ 2 in the AKARI North Ecliptic Pole Deep
... to numerous investigations of samples of star-forming galaxies. Quite naturally these studies focus on galaxies selected either in their UV rest-frame or from their emission in gas recombination lines. A correlation is found between the amount of dust attenuation and the stellar mass of these galaxi ...
... to numerous investigations of samples of star-forming galaxies. Quite naturally these studies focus on galaxies selected either in their UV rest-frame or from their emission in gas recombination lines. A correlation is found between the amount of dust attenuation and the stellar mass of these galaxi ...
http://arxiv.org/pdf/1401.1510v1.pdf
... Three billion years after the big bang (at redshift z = 2), half of the most massive galaxies were already old, quiescent systems with little to no residual star formation and extremely compact with stellar mass densities at least an order of magnitude larger than in low redshift ellipticals, their ...
... Three billion years after the big bang (at redshift z = 2), half of the most massive galaxies were already old, quiescent systems with little to no residual star formation and extremely compact with stellar mass densities at least an order of magnitude larger than in low redshift ellipticals, their ...
The Destruction of an Oort Cloud in a rich stellar cluster
... preceding the formation of the Sun. This model implies a Solar birth environment rich in stars. Several thousand stars were estimated to have been born before the Sun, thus providing the source for 26 Al and 60 Fe traced in chondritic meteorites. The dynamical fate of the Sun was not addressed, but ...
... preceding the formation of the Sun. This model implies a Solar birth environment rich in stars. Several thousand stars were estimated to have been born before the Sun, thus providing the source for 26 Al and 60 Fe traced in chondritic meteorites. The dynamical fate of the Sun was not addressed, but ...
The MUSIC of galaxy clusters – I. Baryon properties and scaling
... mock observations for X-rays, SZ, lensing as well as optical galaxy counts. This will allow us to study the interrelations between the scaling laws associated with the different observables. In this paper we base our attention on the properties of the baryon content and the SZ effects and will leave ...
... mock observations for X-rays, SZ, lensing as well as optical galaxy counts. This will allow us to study the interrelations between the scaling laws associated with the different observables. In this paper we base our attention on the properties of the baryon content and the SZ effects and will leave ...
Star Captures by Quasar Accretion Disks: A Possible Explanation of
... & Sunyaev 1973; Pringle 1981). We closely follow Goodman (2003), reproducing some equations here for completeness. In order to determine whether a star that plunges through the disk can be captured, we must first obtain the disk surface density profile. ...
... & Sunyaev 1973; Pringle 1981). We closely follow Goodman (2003), reproducing some equations here for completeness. In order to determine whether a star that plunges through the disk can be captured, we must first obtain the disk surface density profile. ...
An extended main-sequence turn-off in the Small
... corresponds to a sequence of single hydrogen-burning stars – is provided by the pair of values ((m − M)0 , AV ) = (18.9, 0.25). The rightmost sequence of stars along the MS is easily explained as being a sequence of binaries (both apparent and real). Indeed, the expected position of equal-mass detac ...
... corresponds to a sequence of single hydrogen-burning stars – is provided by the pair of values ((m − M)0 , AV ) = (18.9, 0.25). The rightmost sequence of stars along the MS is easily explained as being a sequence of binaries (both apparent and real). Indeed, the expected position of equal-mass detac ...
Co-orbiting satellite galaxy structures are still in conflict
... numerous attempts have been made to reconcile the observed satellite structures with a cosmological origin. A proposed scenario is the accretion of groups of satellite galaxies, which would naturally result in them having similar orbital parameters (D’Onghia & Lake 2008; Li & Helmi 2008). However, M ...
... numerous attempts have been made to reconcile the observed satellite structures with a cosmological origin. A proposed scenario is the accretion of groups of satellite galaxies, which would naturally result in them having similar orbital parameters (D’Onghia & Lake 2008; Li & Helmi 2008). However, M ...
The galaxy stellar mass function at 3.5 ≤z ≤ 7.5 in the CANDELS
... particular, Schaerer & de Barros (2009) showed that the model fit to the SEDs of z > 3 galaxies can be significantly improved by the inclusion of the nebular lines and continuum, and inclusion of this contribution also helps to yield more reasonable ages for galaxies at very high redshifts. More rec ...
... particular, Schaerer & de Barros (2009) showed that the model fit to the SEDs of z > 3 galaxies can be significantly improved by the inclusion of the nebular lines and continuum, and inclusion of this contribution also helps to yield more reasonable ages for galaxies at very high redshifts. More rec ...
THE KINEMATICS OF ARP 295 IN Hα EMISSION
... side, and that Arp 295a is receding on its northeastern side. Thus, with respect to their mutual orbit, Arp 295b rotates retrograde and Arp 295a prograde. Stockton found maximum rotation velocities (inclination-corrected) of 300 km s−1 for Arp 295a (with a turnover at r = 40 arcsec) and 245 km s−1 f ...
... side, and that Arp 295a is receding on its northeastern side. Thus, with respect to their mutual orbit, Arp 295b rotates retrograde and Arp 295a prograde. Stockton found maximum rotation velocities (inclination-corrected) of 300 km s−1 for Arp 295a (with a turnover at r = 40 arcsec) and 245 km s−1 f ...
Orbits in a given potential
... So the angular momentum per unit mass h = H/m = r × ṙ is a constant vector, and is perpendicular to r and ṙ ⇒ the particle stays in a plane through the origin which is perpendicular to h ...
... So the angular momentum per unit mass h = H/m = r × ṙ is a constant vector, and is perpendicular to r and ṙ ⇒ the particle stays in a plane through the origin which is perpendicular to h ...
Libra - www.BahaiStudies.net
... Iota Librae is a complex multiple star, 377 light-years from Earth, with both optical and true binary components. The Visible at latitudes between +65° and −90°. primary appears as a blue-white star of magnitude 4.5; it is a Best visible at 21:00 (9 p.m.) during the month of June. binary star indivi ...
... Iota Librae is a complex multiple star, 377 light-years from Earth, with both optical and true binary components. The Visible at latitudes between +65° and −90°. primary appears as a blue-white star of magnitude 4.5; it is a Best visible at 21:00 (9 p.m.) during the month of June. binary star indivi ...
Abstract The Star Formation History of Low Surface Brightness Galaxies
... poorly constrained. These objects tend to be rather blue, contradicting the initial impression that they may simply be faded remnants of higher surface brightness galaxies whose star formation has finished. Other scenarios span a broad range: a young mean age, less dust, a lower metallicity, perhaps ...
... poorly constrained. These objects tend to be rather blue, contradicting the initial impression that they may simply be faded remnants of higher surface brightness galaxies whose star formation has finished. Other scenarios span a broad range: a young mean age, less dust, a lower metallicity, perhaps ...
Master Thesis - Sterrenkunde RU Nijmegen
... This means that small stars are located on the lower left, and large star are found in the top right. The temperature and radius are related to the total mass, structure, composition of the stars. Since the mass and composition change during the evolution, this plot is a useful tool to track the evo ...
... This means that small stars are located on the lower left, and large star are found in the top right. The temperature and radius are related to the total mass, structure, composition of the stars. Since the mass and composition change during the evolution, this plot is a useful tool to track the evo ...
The ROSAT galactic plane survey: ASTRONOMY AND
... correlation of RGPS source positions with astronomical catalogues, mostly extracted from the SIMBAD database. The historical development of astronomy has favoured galactic studies and the number of Milky Way objects held in catalogues is rather large. With the positional accuracy of the survey, up t ...
... correlation of RGPS source positions with astronomical catalogues, mostly extracted from the SIMBAD database. The historical development of astronomy has favoured galactic studies and the number of Milky Way objects held in catalogues is rather large. With the positional accuracy of the survey, up t ...
The visibility of Lyman Alpha Emitters: constraining reionization
... This work is quite close in spirit to the calculations presented in Dayal et al. (2011) wherein the authors used (a) cosmological hydrodynamic simulations run with GADGET-2 to obtain the physical properties of z ≃ 5.7 galaxies, (b) a dust model that took into account the entire star formation histor ...
... This work is quite close in spirit to the calculations presented in Dayal et al. (2011) wherein the authors used (a) cosmological hydrodynamic simulations run with GADGET-2 to obtain the physical properties of z ≃ 5.7 galaxies, (b) a dust model that took into account the entire star formation histor ...
400 YEARS OF STELLAR ROTATION - DFTE
... In 1609 the news reached Venice that a certain Flemish optician had built a special spyglass through which it was possible to see distant objects closer with a magnification of about 4 times. Galileo (or some friends of him) was able just on empirical basis to quickly push the magnification first to ...
... In 1609 the news reached Venice that a certain Flemish optician had built a special spyglass through which it was possible to see distant objects closer with a magnification of about 4 times. Galileo (or some friends of him) was able just on empirical basis to quickly push the magnification first to ...
On the characterisation of the Galactic warp in the Gaia era
... all of your support and patience, aspiring guidance and immense knowledge. You always made time to help and advise me. I have been a pleasure for me to work with you. Also, I really appreciate you being so sensitive and supportive towards women’s right. Thank you Luis for being such an incredible te ...
... all of your support and patience, aspiring guidance and immense knowledge. You always made time to help and advise me. I have been a pleasure for me to work with you. Also, I really appreciate you being so sensitive and supportive towards women’s right. Thank you Luis for being such an incredible te ...
Chap3-Astrometry
... 3.6 Modelling planetary systems(1) Proper motion and parallax In the absence of orbiting companion, there are five observables which describes a star’s angular position on the sky: Equatarial coordinate, α0, δ0, given at a specified epoch (e.g. J2000, and within a specified reference system (IC ...
... 3.6 Modelling planetary systems(1) Proper motion and parallax In the absence of orbiting companion, there are five observables which describes a star’s angular position on the sky: Equatarial coordinate, α0, δ0, given at a specified epoch (e.g. J2000, and within a specified reference system (IC ...
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 ...
Follow-up observations of extremely metal
... compositions that are close to the pristine mixture from Big Bang nucleosynthesis, polluted by one or few supernovae. Aims. Only two dozen stars with ([Fe/H]< −4) are known, and they show a wide range of abundance patterns. It is therefore important to enlarge this sample. We present the first resul ...
... compositions that are close to the pristine mixture from Big Bang nucleosynthesis, polluted by one or few supernovae. Aims. Only two dozen stars with ([Fe/H]< −4) are known, and they show a wide range of abundance patterns. It is therefore important to enlarge this sample. We present the first resul ...
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.