blue light - College of Optometrists
... • John Lawrenson has no prorietary interests in the development or marketing of any product mentioned in this lecture ...
... • John Lawrenson has no prorietary interests in the development or marketing of any product mentioned in this lecture ...
The Galactic Halo
... elements (including the lowest [Fe/H] star yet discovered), and lack of over-abundances of neutron-capture elements (CEMP-no stars) Associated with production by “faint SNe” – progenitors with mass on the order of 10-100 Mo undergoing mixing and fallback, or rapidly rotating mega metal-poor (MMP; [F ...
... elements (including the lowest [Fe/H] star yet discovered), and lack of over-abundances of neutron-capture elements (CEMP-no stars) Associated with production by “faint SNe” – progenitors with mass on the order of 10-100 Mo undergoing mixing and fallback, or rapidly rotating mega metal-poor (MMP; [F ...
masses of star clusters in the nuclei of bulgeless spiral galaxies
... broadening function, often approximated as a Gaussian. The line width in the template spectra represents both the intrinsic width of the stellar photospheric lines and the instrumental broadening. The galaxy spectra of unresolved populations are presumed to differ only by the additional Doppler broa ...
... broadening function, often approximated as a Gaussian. The line width in the template spectra represents both the intrinsic width of the stellar photospheric lines and the instrumental broadening. The galaxy spectra of unresolved populations are presumed to differ only by the additional Doppler broa ...
A pyramid wavefront sensor with no dynamic modulation
... case of uniform illumination across the sub-aperture. A function for W~ ðx; yÞ with a much higher spatial frequency than the inverse of the sampling sub-aperture will be better suited at the edges but it will produce a larger amount of scattered light. On this basis one should find a compromise and c ...
... case of uniform illumination across the sub-aperture. A function for W~ ðx; yÞ with a much higher spatial frequency than the inverse of the sampling sub-aperture will be better suited at the edges but it will produce a larger amount of scattered light. On this basis one should find a compromise and c ...
Working with Magnitudes and Color Indices 1 A quick review of
... As the individual stars evolve (age) in the galaxy, the color index of that galaxy will also evolve. The primary reason for this is that the rate of evolution depends on the mass of the star, as does the color index. Thus the high mass stars, which tend to pull the B −V index negative because of the ...
... As the individual stars evolve (age) in the galaxy, the color index of that galaxy will also evolve. The primary reason for this is that the rate of evolution depends on the mass of the star, as does the color index. Thus the high mass stars, which tend to pull the B −V index negative because of the ...
Evolution of the Mass-to-light Ratio of Galaxies to z~0.25
... SDSS images and calibrated, smoothed HI spectra of the 12 fully reduced detections. The size of each SDSS image is 1.5' (the size of the Arecibo beam at 1.2 GHz is ~4'). The red line in each spectrum indicates the frequency corresponding to z from the SDSS. The panel under each spectrum shows the pe ...
... SDSS images and calibrated, smoothed HI spectra of the 12 fully reduced detections. The size of each SDSS image is 1.5' (the size of the Arecibo beam at 1.2 GHz is ~4'). The red line in each spectrum indicates the frequency corresponding to z from the SDSS. The panel under each spectrum shows the pe ...
The Naked-eye Optical Transient OT 120926 Yue Zhao Department
... The constellation Bootes was observed from Brampton, Ontario, Canada (79.7667 W, 43.6833 N) by J. Sandal on the evening of 2012 September 25 local time (MJD 56195; UTC 2012 September 26) using a Sony DSC-W570 18.2 Mpix handheld digital camera. These unfiltered observations reveal an optical transien ...
... The constellation Bootes was observed from Brampton, Ontario, Canada (79.7667 W, 43.6833 N) by J. Sandal on the evening of 2012 September 25 local time (MJD 56195; UTC 2012 September 26) using a Sony DSC-W570 18.2 Mpix handheld digital camera. These unfiltered observations reveal an optical transien ...
Sunlight bending through ice crystals in cirriform clouds
... White and Colors We know from Chapter 2 that nearly half of the solar radiation that reaches the atmosphere is in the form of visible light. As sunlight enters the atmosphere, it is either absorbed, reflected, scattered, or transmitted on through. How objects at the surface respond to this energy de ...
... White and Colors We know from Chapter 2 that nearly half of the solar radiation that reaches the atmosphere is in the form of visible light. As sunlight enters the atmosphere, it is either absorbed, reflected, scattered, or transmitted on through. How objects at the surface respond to this energy de ...
Interpretation of the Helix Planetary Nebula using Hydro
... luminous mass of stars and the more diffusive NBDM-ISM (CDM) mass. The million trillion-planet-PGCs per galaxy each have fossil-density ρ0 ≈ ρP GC ≈ ×104 greater than the hρg i ≈ 10−21 kg m−3 galaxy average and ≈ ×109 hρU i, where hρU i ≈ 10−26 kg m−3 is the flat universe average density at the pr ...
... luminous mass of stars and the more diffusive NBDM-ISM (CDM) mass. The million trillion-planet-PGCs per galaxy each have fossil-density ρ0 ≈ ρP GC ≈ ×104 greater than the hρg i ≈ 10−21 kg m−3 galaxy average and ≈ ×109 hρU i, where hρU i ≈ 10−26 kg m−3 is the flat universe average density at the pr ...
Original-transparency-a-few
... A specific mode of action: Silver atoms The photo chromic mechanism that takes place in a glass photo chromic lens isvery different from what happens with plastic. The light-reactive properties of silver atoms have long been known. Photography is a key example, but in this field, the process is not ...
... A specific mode of action: Silver atoms The photo chromic mechanism that takes place in a glass photo chromic lens isvery different from what happens with plastic. The light-reactive properties of silver atoms have long been known. Photography is a key example, but in this field, the process is not ...
Determination of the distance to the Andromeda Galaxy using variable stars U
... where b and v are the instrumental magnitudes, B and V the standard magnitudes, and Ai are the transformation coefficients. The resulting mean standard deviation of the fits is 0.02 mag. The transformation coefficients cannot be directly applied to the M 31 instrumental magnitudes because the latter are ...
... where b and v are the instrumental magnitudes, B and V the standard magnitudes, and Ai are the transformation coefficients. The resulting mean standard deviation of the fits is 0.02 mag. The transformation coefficients cannot be directly applied to the M 31 instrumental magnitudes because the latter are ...