![Xiao Yang Xia](http://s1.studyres.com/store/data/008084377_1-53a4a6c7e357f5b7c9ce3e0523462954-300x300.png)
Xiao Yang Xia
... NLS1s is mainly from the central AGN, the infrared excess, especially farinfrared excess of IR QSOs should come from starbursts. (2) Star formation rate and accretion rate onto the central BH in IR QSOs at low redshift follow Mbulge- MBH relation, i.e., the ratio of the star formation rate and the a ...
... NLS1s is mainly from the central AGN, the infrared excess, especially farinfrared excess of IR QSOs should come from starbursts. (2) Star formation rate and accretion rate onto the central BH in IR QSOs at low redshift follow Mbulge- MBH relation, i.e., the ratio of the star formation rate and the a ...
Direct Detection of Galactic Halo Dark Matter
... photographic plates in the R59F and BJ passbands from the SuperCOSMOS Sky Survey (12–14). R59F and BJ roughly correspond to optical wavelengths of 0.59 and 0.45 m, respectively. We searched for objects with proper motions, , between 0.33 and 10.00⬙ year⫺1 as faint as R59F ⫽ 19.8, using plates near ...
... photographic plates in the R59F and BJ passbands from the SuperCOSMOS Sky Survey (12–14). R59F and BJ roughly correspond to optical wavelengths of 0.59 and 0.45 m, respectively. We searched for objects with proper motions, , between 0.33 and 10.00⬙ year⫺1 as faint as R59F ⫽ 19.8, using plates near ...
Newton`s Law of Universal Gravitation
... both objects was doubled, and if the distance between the objects remained the same, then what would be the new force of attraction between the two objects? 4. Suppose that two objects attract each other with a gravitational force of 16 units. If the mass of both objects was doubled, and if the dist ...
... both objects was doubled, and if the distance between the objects remained the same, then what would be the new force of attraction between the two objects? 4. Suppose that two objects attract each other with a gravitational force of 16 units. If the mass of both objects was doubled, and if the dist ...
Distance Measurement in Astronomy
... The direction of Centauri is measured against the background of the distant stars at the two points P1 and P2. The angle 2A is measured and so the parallax (angle A) can be found. If you know the angle A and the radius of the Earth’s orbit (R) you can find the distance of the star (D). Stars that ...
... The direction of Centauri is measured against the background of the distant stars at the two points P1 and P2. The angle 2A is measured and so the parallax (angle A) can be found. If you know the angle A and the radius of the Earth’s orbit (R) you can find the distance of the star (D). Stars that ...
EarthComm_c1s9
... have to get above Earth’s atmosphere. The Hubble Space Telescope, for example, can detect objects as dim as 30th magnitude. Perhaps you have seen a star described as a G-type star or an O-type star. This is a way of classifying stars that depends on the color and temperature of the star. They also h ...
... have to get above Earth’s atmosphere. The Hubble Space Telescope, for example, can detect objects as dim as 30th magnitude. Perhaps you have seen a star described as a G-type star or an O-type star. This is a way of classifying stars that depends on the color and temperature of the star. They also h ...
Plotting Variable Stars on the H
... Stars, J B Taylor, © 2006 Miras and Cepheids are especially elongated because of these expansions and contractions. Some pulsating variable stars change in temperature by two spectral classes during one cycle of change from maximum to minimum. To better understand the degree of variation for individ ...
... Stars, J B Taylor, © 2006 Miras and Cepheids are especially elongated because of these expansions and contractions. Some pulsating variable stars change in temperature by two spectral classes during one cycle of change from maximum to minimum. To better understand the degree of variation for individ ...
talk.wyse - Johns Hopkins University
... Expect dark matter scale length to be at least equal to stellar scale length (gas dissipates prior to star formation) Extreme baryon loss in dSph – expand to new equilibrium (?) ...
... Expect dark matter scale length to be at least equal to stellar scale length (gas dissipates prior to star formation) Extreme baryon loss in dSph – expand to new equilibrium (?) ...
Chapter 3 Cosmology 3.1 The Doppler effect
... Astronomers in 1998 studying type Ia supernova were astounded when they discovered very distant supernovae much further away than expected. To reach such distances, they must have been accelerating. The astronomers concluded that the expansion of the Universe is accelerating and has been for about t ...
... Astronomers in 1998 studying type Ia supernova were astounded when they discovered very distant supernovae much further away than expected. To reach such distances, they must have been accelerating. The astronomers concluded that the expansion of the Universe is accelerating and has been for about t ...
ppt document - FacStaff Home Page for CBU
... Giant elliptical galaxies are rare, but can contain the mass of a trillion stars and be 2 million light years in diameter. Dwarf elliptical galaxies are very common, and contain the mass of only a few million stars. Elliptical galaxies are also classified by their roundness as viewed from the earth. ...
... Giant elliptical galaxies are rare, but can contain the mass of a trillion stars and be 2 million light years in diameter. Dwarf elliptical galaxies are very common, and contain the mass of only a few million stars. Elliptical galaxies are also classified by their roundness as viewed from the earth. ...
Gilmore - Astrometry and Astrophysics in the Gaia sky
... • Physical properties, for example: – clean Hertzsprung-Russell sequences throughout the Galaxy – solar neighbourhood mass function and luminosity function e.g. white dwarfs (~200,000) and brown dwarfs (~50,000) – initial mass and luminosity functions in star forming regions – luminosity function fo ...
... • Physical properties, for example: – clean Hertzsprung-Russell sequences throughout the Galaxy – solar neighbourhood mass function and luminosity function e.g. white dwarfs (~200,000) and brown dwarfs (~50,000) – initial mass and luminosity functions in star forming regions – luminosity function fo ...
It`s cosmic! - NSW Department of Education
... Each galaxy is a very large spinning structure. It contains billions of stars. It also contains clouds of gas and dust called nebulas. Some of the stars, like our Sun, have planets. All these things are held together in each galaxy by gravitational forces. (You feel a gravitational force on Earth. I ...
... Each galaxy is a very large spinning structure. It contains billions of stars. It also contains clouds of gas and dust called nebulas. Some of the stars, like our Sun, have planets. All these things are held together in each galaxy by gravitational forces. (You feel a gravitational force on Earth. I ...
Hubble Space Telescope Image
... As predicted by Einstein’s General Theory of Relativity, a compact intervening object is bending and distorting light from individual members of this cluster so that we see a halo effect. ...
... As predicted by Einstein’s General Theory of Relativity, a compact intervening object is bending and distorting light from individual members of this cluster so that we see a halo effect. ...
Distance - Fixed Earth
... catalog of objects having very large redshifts shows that among 109 quasi-stellar objects, in which both absorption and emissions lines could be measured, the value of the absorption redshift in a given object, is always different from the one measured in emission for the same object. It is clear th ...
... catalog of objects having very large redshifts shows that among 109 quasi-stellar objects, in which both absorption and emissions lines could be measured, the value of the absorption redshift in a given object, is always different from the one measured in emission for the same object. It is clear th ...
Hertzsprung-Russell Diagram Outline
... Flux is the power per unit area received from an object, e.g. fsun = 1 kW/m2 If two stars, A and B, have fluxes, fA and fB, their magnitudes are related by ...
... Flux is the power per unit area received from an object, e.g. fsun = 1 kW/m2 If two stars, A and B, have fluxes, fA and fB, their magnitudes are related by ...
Scientific Notation Worksheet
... Name; _____________________________________ Date: ____________ Per: _____ ...
... Name; _____________________________________ Date: ____________ Per: _____ ...
Draft Science Cases for KPAO
... and the size of the subapertures. For a given system, the guide star magnitude determines the sky coverage and the achievable image quality. The promise of LGS is to increase (shift) the sensitivity of a given AO system with respect to NGS by (roughly) (D/d)2 (where D is the telescope diameter and d ...
... and the size of the subapertures. For a given system, the guide star magnitude determines the sky coverage and the achievable image quality. The promise of LGS is to increase (shift) the sensitivity of a given AO system with respect to NGS by (roughly) (D/d)2 (where D is the telescope diameter and d ...
Looking for life in unlikely places: reasons why planets may not be
... will be re-emitted and reflected into a beam pointing back at the Sun. Like the eyes of a moose in Canada or the eyes of a rabbit in New Zealand, any sunflower alive on the surface will then be 25 times brighter than its surroundings, assuming that the illuminated surface at the focus of the concentra ...
... will be re-emitted and reflected into a beam pointing back at the Sun. Like the eyes of a moose in Canada or the eyes of a rabbit in New Zealand, any sunflower alive on the surface will then be 25 times brighter than its surroundings, assuming that the illuminated surface at the focus of the concentra ...
Stellar Continua
... I. The Paschen Continuum • The Paschen continuum slope (B-V) is a good temperature indicator • Varies smoothly with changing temperature • Slope is negative (blue is brighter) for hot stars and positive (visual is brighter) for cooler stars • B-V works as a temperature indicator from 3500K to 9000K ...
... I. The Paschen Continuum • The Paschen continuum slope (B-V) is a good temperature indicator • Varies smoothly with changing temperature • Slope is negative (blue is brighter) for hot stars and positive (visual is brighter) for cooler stars • B-V works as a temperature indicator from 3500K to 9000K ...
THE HR DIAGRAM
... Late in the nineteenth century, astronomers had tools that revealed a great deal about stars. By that time, advances in telescope design and photographic emulsions were becoming mature. They were able to take spectral images of stars which revealed their composition and th ...
... Late in the nineteenth century, astronomers had tools that revealed a great deal about stars. By that time, advances in telescope design and photographic emulsions were becoming mature. They were able to take spectral images of stars which revealed their composition and th ...
The Milky Way and Its Neighbors
... 2)Mapping HII regions via Hα emission lines - HII regions trace active star formation Old data showed that there were 4 arms New data from Spitzer indicates that there are only 2 major spiral arms: -Scutum and Perseus Arms ...
... 2)Mapping HII regions via Hα emission lines - HII regions trace active star formation Old data showed that there were 4 arms New data from Spitzer indicates that there are only 2 major spiral arms: -Scutum and Perseus Arms ...
Object A
... • Work with a partner! • Read the instructions and questions carefully. • Discuss the concepts and your answers with one ...
... • Work with a partner! • Read the instructions and questions carefully. • Discuss the concepts and your answers with one ...
*Studying Complex Star-Forming Fields: Rosette Nebula and Monoceros Loop by Chris Hathaway and Anthony Kuchera
... projected in the sky, the massive stars of the layer are spread all over the field, indicating a large apparent depth of this star-forming region. OB associations can also be detected kinematically as their internal velocity dispersion is usually small. To further confirm our findings, we searched ...
... projected in the sky, the massive stars of the layer are spread all over the field, indicating a large apparent depth of this star-forming region. OB associations can also be detected kinematically as their internal velocity dispersion is usually small. To further confirm our findings, we searched ...
Devika kamath Institute of Astronomy, KU. Leuven, Belgium
... Majority of them show disc-like SEDs (=> binaries) ...
... Majority of them show disc-like SEDs (=> binaries) ...
An introduce of the spectrograph of the GALEX
... redshift range from z=0 to z~3. (...) The derived redshift distribution of the sources detected by our survey peaks at around z=0.6-1.0 (the location of the peak being affected by cosmic variance) and decays monotonically from z~1 to z~3. (...) The cosmic star formation rate (SFR) density goes as (1 ...
... redshift range from z=0 to z~3. (...) The derived redshift distribution of the sources detected by our survey peaks at around z=0.6-1.0 (the location of the peak being affected by cosmic variance) and decays monotonically from z~1 to z~3. (...) The cosmic star formation rate (SFR) density goes as (1 ...
Malmquist bias
The Malmquist bias is an effect in observational astronomy which leads to the preferential detection of intrinsically bright objects. It was first described in 1922 by Swedish astronomer Gunnar Malmquist (1893–1982), who then greatly elaborated upon this work in 1925. In statistics, this bias is referred to as a selection bias and affects the survey results in a brightness limited survey, where stars below a certain apparent brightness are not included. Since observed stars and galaxies appear dimmer when farther away, the brightness that is measured will fall off with distance until their brightness falls below the observational threshold. Objects which are more luminous, or intrinsically brighter, can be observed at a greater distance, creating a false trend of increasing intrinsic brightness, and other related quantities, with distance. This effect has led to many spurious claims in the field of astronomy. Properly correcting for these effects has become an area of great focus.