Teil 2
... orbital motion, i.e., they appear centred at the central meridian during the respective quadrature phases, thus are not facing each other as would be the case for a hypothetical reflection effect. The leading hemispheres on both components appear with an effectively lower temperature than the traili ...
... orbital motion, i.e., they appear centred at the central meridian during the respective quadrature phases, thus are not facing each other as would be the case for a hypothetical reflection effect. The leading hemispheres on both components appear with an effectively lower temperature than the traili ...
ASTRONOMIA SPAIN inglés.qxd
... These are some of the results we present in ‘Astronomy made in Spain’, a project of the Spanish Astronomical Society (Sociedad Española de Astronomía, SEA) to commemorate the International Year of Astronomy 2009. This book is a collection of conversations with the Spanish astronomers who have publis ...
... These are some of the results we present in ‘Astronomy made in Spain’, a project of the Spanish Astronomical Society (Sociedad Española de Astronomía, SEA) to commemorate the International Year of Astronomy 2009. This book is a collection of conversations with the Spanish astronomers who have publis ...
3011800000810
... of 10 of these sources discovered during regular scans of the Galactic plane with the Imager on board INTEGRAL (IBIS; Ubertini et al. 2003) through the end of 2004. They all exhibit very high intrinsic photoabsorption (NH k 1023 cm2) resulting in hard spectra with power-law spectral indices 0:5 < ...
... of 10 of these sources discovered during regular scans of the Galactic plane with the Imager on board INTEGRAL (IBIS; Ubertini et al. 2003) through the end of 2004. They all exhibit very high intrinsic photoabsorption (NH k 1023 cm2) resulting in hard spectra with power-law spectral indices 0:5 < ...
Extreme abundance ratios in the polluted atmosphere of the cool
... Polluted white dwarfs (typed with a suffix ‘Z’) provide an opportunity to investigate the ultimate fate of planetary systems. Although planets have not yet been detected around white dwarfs, the evidence for the presence of planetary debris around these objects lies in their polluted atmospheres. Ap ...
... Polluted white dwarfs (typed with a suffix ‘Z’) provide an opportunity to investigate the ultimate fate of planetary systems. Although planets have not yet been detected around white dwarfs, the evidence for the presence of planetary debris around these objects lies in their polluted atmospheres. Ap ...
Slide 1
... Gravitational Instability (GI) When a disk patch with size L starts collapsing it has the following ...
... Gravitational Instability (GI) When a disk patch with size L starts collapsing it has the following ...
Improved stellar parameters of CoRoT-7
... our solar system, a so-called super Earth. The mass was determined using ground-based follow-up spectroscopy, which also revealed a second, non-transiting super Earth. Aims. These planets are orbiting a relatively faint (mV = 11.7) G9V star called CoRoT-7. We wish to refine the determination of the ...
... our solar system, a so-called super Earth. The mass was determined using ground-based follow-up spectroscopy, which also revealed a second, non-transiting super Earth. Aims. These planets are orbiting a relatively faint (mV = 11.7) G9V star called CoRoT-7. We wish to refine the determination of the ...
How Massive Single Stars End Their Life - TigerPrints
... helium core increases, so does its binding energy and entropy. Because of its higher entropy, a larger helium core also has, on the average, a larger iron core mass and a shallower density gradient around that core (Woosley et al. 2002). Consequently, such stars are harder to explode (Fryer 1999; Fr ...
... helium core increases, so does its binding energy and entropy. Because of its higher entropy, a larger helium core also has, on the average, a larger iron core mass and a shallower density gradient around that core (Woosley et al. 2002). Consequently, such stars are harder to explode (Fryer 1999; Fr ...
Resources: - Real Science
... European Space Agency's X-ray satellite, XMM-Newton, and NASA's Swift X-ray and gamma-ray observatory. Just five days before the burst, Muno and his collaborators had been looking at the magnetar with XMM-Newton. They saw it in the relatively calm state in which he had first found it. As most magnet ...
... European Space Agency's X-ray satellite, XMM-Newton, and NASA's Swift X-ray and gamma-ray observatory. Just five days before the burst, Muno and his collaborators had been looking at the magnetar with XMM-Newton. They saw it in the relatively calm state in which he had first found it. As most magnet ...
Explosion and Systematics for Core
... We propose a novel approach to the study the connection between progenitors and the properties of core-collapse supernovae, based on a physically motivated mechanism for launching the explosions, namely neutrino energy deposition. Although the viability of this explosion mechanism is still under deb ...
... We propose a novel approach to the study the connection between progenitors and the properties of core-collapse supernovae, based on a physically motivated mechanism for launching the explosions, namely neutrino energy deposition. Although the viability of this explosion mechanism is still under deb ...
Determination of the distance to the Andromeda Galaxy using variable stars U
... a few times 1032 erg up to 1033 erg in B, which are characteristic of a short-term impulsive flares rather than microflares. When analyzing the decay phase of the light curve of flare A, three other short term increases can be identified. Since those events occurred simultaneously in both colors, we ...
... a few times 1032 erg up to 1033 erg in B, which are characteristic of a short-term impulsive flares rather than microflares. When analyzing the decay phase of the light curve of flare A, three other short term increases can be identified. Since those events occurred simultaneously in both colors, we ...
Star Formation in the Rosette Complex
... map of the Rosette Complex using the Arecibo telescope. They found that neutral gas in the Rosette Complex is distributed in three main regions which form a rough, extended shell of about 45 pc in radius around the nebula and extend beyond the molecular cloud. This shell would have a center of expan ...
... map of the Rosette Complex using the Arecibo telescope. They found that neutral gas in the Rosette Complex is distributed in three main regions which form a rough, extended shell of about 45 pc in radius around the nebula and extend beyond the molecular cloud. This shell would have a center of expan ...
Session 1: Stellar winds, diagnostics across the electromagnetic
... rates? J.O. Sundqvist, J. Puls, A. Feldmeier, S.P. Owocki Small-scale inhomogeneities, or "clumping", in the winds of hot, massive stars are conventionally included in spectral analyses by the so-called microclumping technique. To reconcile investigations of different diagnostics using this techniqu ...
... rates? J.O. Sundqvist, J. Puls, A. Feldmeier, S.P. Owocki Small-scale inhomogeneities, or "clumping", in the winds of hot, massive stars are conventionally included in spectral analyses by the so-called microclumping technique. To reconcile investigations of different diagnostics using this techniqu ...
Masses, Radii, and Equation of State of Neutron Stars
... have enabled significant recent developments in our ability to model these extreme objects and interpret the observations in solid frameworks. We now know precise masses for ∼ 35 neutron stars spanning the range from 1.17 to 2.0 M⊙ and can pin down the radii of more than a dozen to the 9.9−11.2 km r ...
... have enabled significant recent developments in our ability to model these extreme objects and interpret the observations in solid frameworks. We now know precise masses for ∼ 35 neutron stars spanning the range from 1.17 to 2.0 M⊙ and can pin down the radii of more than a dozen to the 9.9−11.2 km r ...
... Lucchini (2014) investigate various accretion models for driving jets from known pre-planetary nebulae, and rule out most modes of accretion, including Bondi-Hoyle-Lyttleton wind accretion and wind Roche-lobe overflow, based on observed jet power. Roche-lobe overflow is possible, and accretion within ...
Planet Formation: Disk Formation and Evolution
... In order for molecular clouds to collapse and commence the star formation process, they must rid themselves of this magnetic support. The process which removes magnetic pressure from molecular clouds is called ambipolar diffusion (Mestel & Spitzer 1956, Mouschovias 1976). In this process there is a ...
... In order for molecular clouds to collapse and commence the star formation process, they must rid themselves of this magnetic support. The process which removes magnetic pressure from molecular clouds is called ambipolar diffusion (Mestel & Spitzer 1956, Mouschovias 1976). In this process there is a ...
Models of the Structure and Evolution of Protoplanetary Disks
... steep. The SEDs of Herbig Ae/Be stars show a similar picture, but with a somewhat larger spread in s, although it must be kept in mind that the determination of the slope of a bumpy SED like in Fig. 2 is somewhat subjective. Meeus et al. (2001, henceforth M01) divide the SEDs of Herbig Ae/Be stars i ...
... steep. The SEDs of Herbig Ae/Be stars show a similar picture, but with a somewhat larger spread in s, although it must be kept in mind that the determination of the slope of a bumpy SED like in Fig. 2 is somewhat subjective. Meeus et al. (2001, henceforth M01) divide the SEDs of Herbig Ae/Be stars i ...
Systematic variation in the apparent burning area of thermonuclear
... well as the natural expectation that T BB primarily decreases during decay, implies that f decreases as T BB decreases for short-duration bursts, and f increases as T BB decreases for long-duration bursts. According to the current theoretical results, the former f versus T BB relation is possible fo ...
... well as the natural expectation that T BB primarily decreases during decay, implies that f decreases as T BB decreases for short-duration bursts, and f increases as T BB decreases for long-duration bursts. According to the current theoretical results, the former f versus T BB relation is possible fo ...
Star formation rates and efficiencies in the Galactic Centre
... The measured column density of hydrogen in the CMZ appears to be at least an order of magnitude higher than clouds within the disc (> 1022 cm−2 ; Rathborne et al. 2014b; Battersby et al. in prep), implying an average gas volume density above ∼ 104 cm−3 . However, if the gas is more extended along th ...
... The measured column density of hydrogen in the CMZ appears to be at least an order of magnitude higher than clouds within the disc (> 1022 cm−2 ; Rathborne et al. 2014b; Battersby et al. in prep), implying an average gas volume density above ∼ 104 cm−3 . However, if the gas is more extended along th ...
English version - Richard de Grijs
... and magnetic axis orientations influence what kind of emission is seen on Earth. Geminga may have magnetic poles quite close to the top and bottom of the object, and nearly aligned spin poles, much like Earth. One of the magnetic poles of B0355+54 could directly face the Earth. Because the radio ...
... and magnetic axis orientations influence what kind of emission is seen on Earth. Geminga may have magnetic poles quite close to the top and bottom of the object, and nearly aligned spin poles, much like Earth. One of the magnetic poles of B0355+54 could directly face the Earth. Because the radio ...
Stars, neutral hydrogen and ionised gas in early
... as 5.9×109 M . On the basis of these observations, we included IC 4200 in our sample for the study of the relation between stellar and H i properties in early-type galaxies. We characterised the environment of IC 4200 by looking for extragalactic objects within 100 arcmin (∼1.6 Mpc at this redshift ...
... as 5.9×109 M . On the basis of these observations, we included IC 4200 in our sample for the study of the relation between stellar and H i properties in early-type galaxies. We characterised the environment of IC 4200 by looking for extragalactic objects within 100 arcmin (∼1.6 Mpc at this redshift ...
Z - STScI
... 56Ni explosively created from Si burning after corecollapse Direct probe of the explosion How Is it related to progenitor mass ? ...
... 56Ni explosively created from Si burning after corecollapse Direct probe of the explosion How Is it related to progenitor mass ? ...
Cygnus X-1
Cygnus X-1 (abbreviated Cyg X-1) is a well-known galactic X-ray source, thought to be a black hole, in the constellation Cygnus. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources seen from Earth, producing a peak X-ray flux density of 6977229999999999999♠2.3×10−23 Wm−2 Hz−1 (7003230000000000000♠2.3×103 Jansky). Cygnus X-1 was the first X-ray source widely accepted to be a black hole and it remains among the most studied astronomical objects in its class. The compact object is now estimated to have a mass about 14.8 times the mass of the Sun and has been shown to be too small to be any known kind of normal star, or other likely object besides a black hole. If so, the radius of its event horizon is about 7004440000000000000♠44 km.Cygnus X-1 belongs to a high-mass X-ray binary system about 7019574266339685654♠6070 ly from the Sun that includes a blue supergiant variable star designated HDE 226868 which it orbits at about 0.2 AU, or 20% of the distance from the Earth to the Sun. A stellar wind from the star provides material for an accretion disk around the X-ray source. Matter in the inner disk is heated to millions of degrees, generating the observed X-rays. A pair of jets, arranged perpendicular to the disk, are carrying part of the energy of the infalling material away into interstellar space.This system may belong to a stellar association called Cygnus OB3, which would mean that Cygnus X-1 is about five million years old and formed from a progenitor star that had more than 7001400000000000000♠40 solar masses. The majority of the star's mass was shed, most likely as a stellar wind. If this star had then exploded as a supernova, the resulting force would most likely have ejected the remnant from the system. Hence the star may have instead collapsed directly into a black hole.Cygnus X-1 was the subject of a friendly scientific wager between physicists Stephen Hawking and Kip Thorne in 1975, with Hawking betting that it was not a black hole. He conceded the bet in 1990 after observational data had strengthened the case that there was indeed a black hole in the system. This hypothesis has not been confirmed due to a lack of direct observation but has generally been accepted from indirect evidence.