Unit4
... Optical Spectrum Analysis OSA Consists of a tunable bandpass filter and an optical power meter The light from the input fibre is collimated and applied to the diffraction grating The diffraction grating separates the input light into different angles depending on wavelength The light from the gratin ...
... Optical Spectrum Analysis OSA Consists of a tunable bandpass filter and an optical power meter The light from the input fibre is collimated and applied to the diffraction grating The diffraction grating separates the input light into different angles depending on wavelength The light from the gratin ...
The 3-D shaping of NGC 6741: a massive, fast
... semi-axes, respectively), surrounded by a sharp low-excitation skin (the ionization front), and embedded into a spherical (radius≃0.080 pc), almost-neutral, high-density (n(H I) ≃7×103 atoms cm−3 ) halo containing a large fraction of the nebular mass (Mhalo ≥0.20 M⊙ ). The kinematics, physical condi ...
... semi-axes, respectively), surrounded by a sharp low-excitation skin (the ionization front), and embedded into a spherical (radius≃0.080 pc), almost-neutral, high-density (n(H I) ≃7×103 atoms cm−3 ) halo containing a large fraction of the nebular mass (Mhalo ≥0.20 M⊙ ). The kinematics, physical condi ...
IV Interstellar Dust
... How important is dust? In our Galaxy the gas-to-dust ratio is about 100:1. Since the ISM is about 10% of the baryonic mass of the Galaxy, dust grains comprise roughly 0.1% of the total. At the same time, they absorb roughly 30-50% of the starlight emitted by the Galaxy and re-radiate it as farinfrar ...
... How important is dust? In our Galaxy the gas-to-dust ratio is about 100:1. Since the ISM is about 10% of the baryonic mass of the Galaxy, dust grains comprise roughly 0.1% of the total. At the same time, they absorb roughly 30-50% of the starlight emitted by the Galaxy and re-radiate it as farinfrar ...
High spatial resolution performance of a triple Fabry–Pérot filtergraph
... within the channeled spectrum. Several filtergraphs using FPIs have been recently constructed for solar observations (Bonaccini et al. 1989; Bendlin et al. 1992; Cavallini 1998; Kentischer et al. 1998). The spectral passband of an FPI varies with the angle of incidence of a plane wave which transver ...
... within the channeled spectrum. Several filtergraphs using FPIs have been recently constructed for solar observations (Bonaccini et al. 1989; Bendlin et al. 1992; Cavallini 1998; Kentischer et al. 1998). The spectral passband of an FPI varies with the angle of incidence of a plane wave which transver ...
Giant molecular clouds in the Local Group galaxy M 33⋆⋆⋆
... Figure 1 shows the scaling law between the size and the linewidth for the M 33 clouds. No apparent correlation is visible between the size and linewidth and there is a large scatter in the linewidths. The bulk of the points lie below the scaling law found by SRBY in the Milky Way. The use of second ...
... Figure 1 shows the scaling law between the size and the linewidth for the M 33 clouds. No apparent correlation is visible between the size and linewidth and there is a large scatter in the linewidths. The bulk of the points lie below the scaling law found by SRBY in the Milky Way. The use of second ...
Determination of the distance to the Andromeda Galaxy using variable stars U
... up similarities and differences between solar and stellar flares is to continuously broaden the ensemble of analyzed flares (solar and stellar as well), thus making an observational base of different types of flaring activities available for theoretical purposes. This is how solar flare observations c ...
... up similarities and differences between solar and stellar flares is to continuously broaden the ensemble of analyzed flares (solar and stellar as well), thus making an observational base of different types of flaring activities available for theoretical purposes. This is how solar flare observations c ...
The galaxy stellar mass function at 3.5 ≤z ≤ 7.5 in the CANDELS
... yield more reasonable ages for galaxies at very high redshifts. More recently, the importance of including the nebular contribution has been inferred more directly from observations via analysis of the Spitzer-IRAC photometry of high-redshift galaxies. Shim et al. (2011) reported a strong Hα line co ...
... yield more reasonable ages for galaxies at very high redshifts. More recently, the importance of including the nebular contribution has been inferred more directly from observations via analysis of the Spitzer-IRAC photometry of high-redshift galaxies. Shim et al. (2011) reported a strong Hα line co ...
Clusters: age scales for stellar physics
... In order to define an age scale (or several), it is very important to keep in mind that we cannot make experiments except in very few situations and we rely on observations and theory. Thus, observational phenomena with very well defined ages, our anchors, are extremely important. As a matter of fac ...
... In order to define an age scale (or several), it is very important to keep in mind that we cannot make experiments except in very few situations and we rely on observations and theory. Thus, observational phenomena with very well defined ages, our anchors, are extremely important. As a matter of fac ...
diffraction gratings
... the entrance slit or field-stop. This collimator may be a lens, a mirror or an integral part of the dispersing element, as in a concave grating spectrometer. 3. A dispersing element, usually a grating which spreads the light intensity in space as a function of wavelength. 4. A focusing element to fo ...
... the entrance slit or field-stop. This collimator may be a lens, a mirror or an integral part of the dispersing element, as in a concave grating spectrometer. 3. A dispersing element, usually a grating which spreads the light intensity in space as a function of wavelength. 4. A focusing element to fo ...
Follow-Up Observations of PTFO 8-8695: A 3 MYr Old T
... was found for a stellar companion. The observed optical radial velocity variations (Keck HIRES and HET HRS) were found to be out of phase with the transit events and were not of sufficient amplitude to be caused by a stellar companion, arguing that the observed transits were not the result of an ecl ...
... was found for a stellar companion. The observed optical radial velocity variations (Keck HIRES and HET HRS) were found to be out of phase with the transit events and were not of sufficient amplitude to be caused by a stellar companion, arguing that the observed transits were not the result of an ecl ...
The effects of red supergiant mass loss on
... In his seminal paper on the discovery of a wind emanating from the M5-type red supergiant α Herculis, the massive component of a visual binary, Armin Deutsch (1956) laid the foundations for what we know about red supergiant mass loss. The optical, violet-displaced absorption lines were used to infer ...
... In his seminal paper on the discovery of a wind emanating from the M5-type red supergiant α Herculis, the massive component of a visual binary, Armin Deutsch (1956) laid the foundations for what we know about red supergiant mass loss. The optical, violet-displaced absorption lines were used to infer ...
PowerPoint 簡報
... Each sequence can be distinguished from a shifted version of itself easily. Each sequence can be distinguished from (a possibly shifted version of) every other sequence in the same set. 成功大學 ...
... Each sequence can be distinguished from a shifted version of itself easily. Each sequence can be distinguished from (a possibly shifted version of) every other sequence in the same set. 成功大學 ...
Presolar History Recorded in Extraterrestrial Materials
... producing a shock wave that expels the stellar matter. could only be explained by nucleosynthetic processes in stars. The laboratory study of stardust has opened a new Traditional astronomy and laboratory studies of stardust window into the inner mechanics of stars and the ancient operate on fundame ...
... producing a shock wave that expels the stellar matter. could only be explained by nucleosynthetic processes in stars. The laboratory study of stardust has opened a new Traditional astronomy and laboratory studies of stardust window into the inner mechanics of stars and the ancient operate on fundame ...
RESONANCE WAVELENGTH DEPENDENCE AND MODE
... resonant modes do not go to zero and show very intense peak at the corners due to non-negligible thickness. Moreover, FDTD simulations reveal that the usually considered linear relation between the resonant wavelength and the nanorod length has to be modified when the nanorod thickness is taken into ...
... resonant modes do not go to zero and show very intense peak at the corners due to non-negligible thickness. Moreover, FDTD simulations reveal that the usually considered linear relation between the resonant wavelength and the nanorod length has to be modified when the nanorod thickness is taken into ...
YourFirstTelescope
... inexpensive lenses are available in aperture sizes of 50mm (2”) to 76mm (3”) in diameter, and new scopes can be purchased in the $100 to $150 price range. The price for one of these scopes can be drastically reduced if they are purchased second hand. These inexpensive scopes can be purchased from re ...
... inexpensive lenses are available in aperture sizes of 50mm (2”) to 76mm (3”) in diameter, and new scopes can be purchased in the $100 to $150 price range. The price for one of these scopes can be drastically reduced if they are purchased second hand. These inexpensive scopes can be purchased from re ...
Manipulating Atoms with Photons
... σ+ transition starting from g+1/2 (see Figure 3). This gives rise to an optical pumping cycle transferring atoms from g−1/2 to g+1/2 through e+1/2 . During such an absorptionspontaneous emission cycle, the angular momentum of the impinging photons has been transferred to the atoms which thus become ...
... σ+ transition starting from g+1/2 (see Figure 3). This gives rise to an optical pumping cycle transferring atoms from g−1/2 to g+1/2 through e+1/2 . During such an absorptionspontaneous emission cycle, the angular momentum of the impinging photons has been transferred to the atoms which thus become ...
What do we know about the evolution/variation with redshift of dust
... Confirmation of the variation of the attenuation curve among galaxies: shape in UV/NIR, UV bump: as a function of the amount of attenuation, stellar mass, ...
... Confirmation of the variation of the attenuation curve among galaxies: shape in UV/NIR, UV bump: as a function of the amount of attenuation, stellar mass, ...
Squeezing the best astrophysics out of Advanced Virgo
... Virgo is currently the second largest gravitational wave detector in the world (3km). Advanced Virgo is an upgrade with 10 times better sensitivity => allows us to scan 1000 times larger volume of the universe than current instruments. Start of Construction in 2009, Design sensitivity in 2015( ...
... Virgo is currently the second largest gravitational wave detector in the world (3km). Advanced Virgo is an upgrade with 10 times better sensitivity => allows us to scan 1000 times larger volume of the universe than current instruments. Start of Construction in 2009, Design sensitivity in 2015( ...
VLT adaptive optics search for luminous substructures in the lens
... We are primarily interested in a clean subtraction of the lens galaxy light within the Einstein radius. To do so, we mask the area of the Einstein ring (quasars and quasar host galaxy). The use of masks ensure that Galfit does not try to fit the ring as a component of the lens galaxy. However, it ca ...
... We are primarily interested in a clean subtraction of the lens galaxy light within the Einstein radius. To do so, we mask the area of the Einstein ring (quasars and quasar host galaxy). The use of masks ensure that Galfit does not try to fit the ring as a component of the lens galaxy. However, it ca ...
Lyman-alpha imaging of starburst galaxies in the local universe and beyond Matthew Hayes
... review can be found in Kennicutt (1998a). For standard initial mass function (IMF; the mass distribution of stars at zero age)1 , the relative abundance of massive stars is small. Since these stars have very short lifetimes (less than the proto-stellar collapse timescale) ongoing star formation is r ...
... review can be found in Kennicutt (1998a). For standard initial mass function (IMF; the mass distribution of stars at zero age)1 , the relative abundance of massive stars is small. Since these stars have very short lifetimes (less than the proto-stellar collapse timescale) ongoing star formation is r ...
Microlensing Events by Proxima Centauri in 2014 and 2016
... To search for such very favorable events, we started with the LHS catalog (Luyten 1979), a compilation of all known stars with proper motions greater than 0′′. 5 yr−1 . The coordinates in the LHS catalog are only approximate, so we used improved positions and proper motions determined by Lépine & S ...
... To search for such very favorable events, we started with the LHS catalog (Luyten 1979), a compilation of all known stars with proper motions greater than 0′′. 5 yr−1 . The coordinates in the LHS catalog are only approximate, so we used improved positions and proper motions determined by Lépine & S ...
Astronomical spectroscopy
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, which radiates from stars and other hot celestial objects. Spectroscopy can be used to derive many properties of distant stars and galaxies, such as their chemical composition, temperature, density, mass, distance, luminosity, and relative motion using Doppler shift measurements.