scholarly journals The stellar distribution in the Galactic spheroid

1985 ◽  
Vol 106 ◽  
pp. 161-162
Author(s):  
Gerard Gilmore
Keyword(s):  
Velocity Field ◽  
Density Profile ◽  
Luminosity Function ◽  
Schmidt Telescope ◽  
Chemical Abundances ◽  
3 Dimensional ◽  
Number Magnitude ◽  
Stellar Velocity ◽  
Dimensional Distribution ◽  
The Uk

Our Galaxy is the only galaxy in which the 3-dimensional distribution of visible mass, chemical abundances and the stellar velocity field are all directly measurable. A project to determine these properties is currently underway, utilising direct photographic plates from the UK Schmidt telescope and the Las Campanas du Pont reflector, and the COSMOS and APM automated measuring machines. These provide reliable number-magnitude-colour distributions for complete samples of stars to V = 19 in 20 square degrees, and V = 22 in 1 square degree, in each of eight directions. These data may then be directly interpreted to determine the density profile, shape and luminosity function of the Galactic spheroid.

scholarly journals An Emission-Line Galaxy Survey with the UK Schmidt Telescope

1987 ◽  
Vol 121 ◽  
pp. 53-55
Author(s):  
M. Kalafi ◽  
A. Savage ◽  
A.R. Good ◽  
R.D. Cannon ◽  
M.G. Yates
Keyword(s):  
Emission Line ◽  
Large Scale ◽  
Preliminary Investigation ◽  
Schmidt Telescope ◽  
Large Area ◽  
Number Magnitude ◽  
Emission Line Galaxies ◽  
Galaxy Populations ◽  
The Uk ◽  
Line Galaxy

The use of objective prisms in conjunction with the large area coverage afforded by Schmidt telescopes provides a very powerful means of detecting large numbers of emission-line galaxies, and allows one to study their large scale distribution. An important question that has yet to be fully addressed is the relationship between the number-magnitude distributions of the normal field galaxy and emission-line galaxy populations. A comparison such as this would effectively probe the evolution with time of these active objects. For example, study of the distant (z = 0.458) cluster of galaxies associated with 3C 295 (Dressler & Gunn 1983) indicates that emission-line objects may have been far more numerous in the past than at present. As a preliminary investigation in advance of a larger project, we report here on a search for emission-line galaxies in four United Kingdom 1.2m Schmidt Telescope (UKST) objective prism fields.

On the Existence of Bright (Mbol < –6) Upper AGB Stars

1987 ◽  
Vol 7 (2) ◽  
pp. 147-150 ◽  
Author(s):  
S. M. G. Hughes ◽  
P. R. Wood
Keyword(s):  
Central Region ◽  
Luminosity Function ◽  
Asymptotic Giant Branch ◽  
Agb Stars ◽  
Schmidt Telescope ◽  
Limited Sample ◽  
Bolometric Luminosity ◽  
Show Evidence ◽  
The Uk ◽  
Process Elements

AbstractA photometric survey of a central region of the LMC has been undertaken to obtain a magnitude and colour limited sample of bright asymptotic giant branch (AGB) stars; the stars were selected from V and Ic plates taken by the UK Schmidt Telescope Unit (UKSTU) at Coonabarabran. Infrared JHK photometry has been obtained for all the stars in the sample in order to determine bolometric magnitudes, and spectra have been obtained for most of the stars to obtain spectral types. Stars in the sample have bolometric magnitudes up to the AGB limit of Mbol ∼ – 7.1, and many of the stars show evidence for dredge-up of carbon and s-process elements during helium shell flashes. A bolometric luminosity function has been constructed and its behaviour is discussed in terms of possible mass loss scenarios.

3-Dimensional immunolabeling and in situ hybridization detection using fluorescence photooxidation and intermediate-voltage Electron Microscopy

1994 ◽  
Vol 52 ◽  
pp. 164-165
Author(s):  
Thomas J. Deerinck ◽  
Maryann E. Martone ◽  
Varda Lev-Ram ◽  
David P. L. Green ◽  
Roger Y. Tsien ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Reactive Oxygen ◽  
Confocal Laser Scanning Microscope ◽  
Fluorescent Dye ◽  
Confocal Laser ◽  
3 Dimensional ◽  
Voltage Electron ◽  
Dimensional Distribution ◽  
Electron Microscopes ◽  
New Generation

The confocal laser scanning microscope has become a powerful tool in the study of the 3-dimensional distribution of proteins and specific nucleic acid sequences in cells and tissues. This is also proving to be true for a new generation of high contrast intermediate voltage electron microscopes (IVEM). Until recently, the number of labeling techniques that could be employed to allow examination of the same sample with both confocal and IVEM was rather limited. One method that can be used to take full advantage of these two technologies is fluorescence photooxidation. Specimens are labeled by a fluorescent dye and viewed with confocal microscopy followed by fluorescence photooxidation of diaminobenzidine (DAB). In this technique, a fluorescent dye is used to photooxidize DAB into an osmiophilic reaction product that can be subsequently visualized with the electron microscope. The precise reaction mechanism by which the photooxidation occurs is not known but evidence suggests that the radiationless transfer of energy from the excited-state dye molecule undergoing the phenomenon of intersystem crossing leads to the formation of reactive oxygen species such as singlet oxygen. It is this reactive oxygen that is likely crucial in the photooxidation of DAB.

scholarly journals The stellar velocity field in M 51

1970 ◽  
Vol 38 ◽  
pp. 79-82
Author(s):  
S. M. Simkin
Keyword(s):  
Velocity Field ◽  
Large Deviations ◽  
Rotation Curve ◽  
Radial Velocities ◽  
Absorption Lines ◽  
Image Tube ◽  
Stellar Velocity

Radial velocities have been measured from the absorption lines on two image tube spectra of M 51. These velocities show large deviations from the ‘smoothed’ rotation curve for that object. The measurements seem to indicate that both the stars and the gas move in the same way.

scholarly journals The global 3-D distribution of tropospheric aerosols as characterized by CALIOP

2013 ◽  
Vol 13 (6) ◽  
pp. 3345-3361 ◽  
Author(s):  
D. M. Winker ◽  
J. L. Tackett ◽  
B. J. Getzewich ◽  
Z. Liu ◽  
M. A. Vaughan ◽  
...  
Keyword(s):  
Lower Troposphere ◽  
Aerosol Extinction ◽  
Transport Pathways ◽  
3 Dimensional ◽  
Clear Sky ◽  
Tropospheric Aerosol ◽  
Vertical Distributions ◽  
Dimensional Distribution ◽  
Level 3 ◽  
Sky Conditions

Abstract. The CALIOP lidar, carried on the CALIPSO satellite, has been acquiring global atmospheric profiles since June 2006. This dataset now offers the opportunity to characterize the global 3-D distribution of aerosol as well as seasonal and interannual variations, and confront aerosol models with observations in a way that has not been possible before. With that goal in mind, a monthly global gridded dataset of daytime and nighttime aerosol extinction profiles has been constructed, available as a Level 3 aerosol product. Averaged aerosol profiles for cloud-free and all-sky conditions are reported separately. This 6-yr dataset characterizes the global 3-dimensional distribution of tropospheric aerosol. Vertical distributions are seen to vary with season, as both source strengths and transport mechanisms vary. In most regions, clear-sky and all-sky mean aerosol profiles are found to be quite similar, implying a lack of correlation between high semi-transparent cloud and aerosol in the lower troposphere. An initial evaluation of the accuracy of the aerosol extinction profiles is presented. Detection limitations and the representivity of aerosol profiles in the upper troposphere are of particular concern. While results are preliminary, we present evidence that the monthly-mean CALIOP aerosol profiles provide quantitative characterization of elevated aerosol layers in major transport pathways. Aerosol extinction in the free troposphere in clean conditions, where the true aerosol extinction is typically 0.001 km−1 or less, is generally underestimated, however. The work described here forms an initial global 3-D aerosol climatology which we plan to extend and improve over time.

scholarly journals The NIBLES bivariate luminosity–H I mass distribution function revised using Arecibo follow-up observations

2020 ◽  
Vol 642 ◽  
pp. A175
Author(s):  
Z. Butcher ◽  
W. van Driel ◽  
S. Schneider
Keyword(s):  
Mass Distribution ◽  
Radio Telescope ◽  
Luminosity Function ◽  
Mass Function ◽  
Bivariate Analysis ◽  
Dimensional Distribution ◽  
Low Mass ◽  
The One ◽  
Mass Distribution Function

We present a modified optical luminosity–H I mass bivariate luminosity function based on H I line observations from the Nançay Interstellar Baryons Legacy Extragalactic Survey (NIBLES), including data from our new, four times more sensitive follow-up H I line observations obtained with the Arecibo radio telescope. The follow-up observations were designed to probe the underlying H I mass distribution of the NIBLES galaxies that were undetected or marginally detected in H I at the Nançay Radio Telescope. Our total follow-up sample consists of 234 galaxies, and it spans the entire luminosity and color range of the parent NIBLES sample of 2600 nearby (900 <  cz <  12 000 km s−1) SDSS galaxies. We incorporated the follow-up data into the bivariate analysis by scaling the NIBLES undetected fraction by an Arecibo-only distribution. We find the resulting increase in low H I mass-to-light ratio densities to be about 10% for the bins −1.0 ≤ log(MHI/M⊙/Lr/L⊙) ≤ −0.5, which produces an increased H I mass function (HIMF) low mass slope of α = −1.14 ± 0.07, being slightly shallower than the values of −1.35 ± 0.05 obtained by recent blind H I surveys. Applying the same correction to the optically corrected bivariate luminosity function from our previous paper produces a larger density increase of about 0.5 to 1 dex in the lowest H I mass-to-light ratio bins for a given luminosity while having a minimal effect on the resulting HIMF low mass slope, which still agrees with blind survey HIMFs. This indicates that while low H I-mass-to-light ratio galaxies do not contribute much to the one-dimensional HIMF, their inclusion has a significant impact on the densities in the two-dimensional distribution.

scholarly journals Low-dispersion spectroscopy of blue stars from the UK Schmidt Telescope UBVRI survey

1992 ◽  
Vol 258 (3) ◽  
pp. 521-526 ◽  
Author(s):  
D. E. Holmgren ◽  
R. J. H. McCausland ◽  
P. L. Dufton ◽  
F. P. Keenan ◽  
D. Kilkenny
Keyword(s):  
Schmidt Telescope ◽  
The Uk ◽  
Low Dispersion

scholarly journals Automated Quasar Detection

1983 ◽  
Vol 104 ◽  
pp. 31-31
Author(s):  
Roger G. Clowes ◽  
John A. Cooke ◽  
Steven M. Beard
Keyword(s):  
Selection Effects ◽  
Schmidt Telescope ◽  
Royal Observatory ◽  
Objective Prism ◽  
Measuring Machine ◽  
The Uk

The existing spectral searches for quasars have increased the number of quasars known very substantially but have not contributed proportionately to an understanding of the collective properties because of the selection effects. To fully exploit the spectral searches we have developed the technique of automated quasar detection (AQD) using objective-prism plates from the UK Schmidt Telescope, the COSMOS measuring machine at the Royal Observatory Edinburgh, and the STARLINK nodes at Durham and Edinburgh.

scholarly journals Objective-Prism Galaxy Redshifts in Fields Around the South Galactic Pole

1984 ◽  
Vol 78 ◽  
pp. 405-408 ◽  
Author(s):  
Q.A. Parker ◽  
H.T. MacGillivray ◽  
R.J. Dodd ◽  
J.A. Cooke ◽  
S.M. Beard ◽  
...  
Keyword(s):  
Large Scale ◽  
Schmidt Telescope ◽  
The South ◽  
Large Numbers ◽  
Objective Prism ◽  
The Uk

AbstractMeasurements made with the COSMOS machine on deep objectiveprism photographs taken with the UK 1.2m Schmidt Telescope are being used to obtain approximate redshifts (accurate to ~ 0.01 in z) for large numbers of galaxies in fields near the South Galactic Pole. The data are suitable for investigations of the distribution of galaxies, such as the detection of large-scale density enhancements or voids.

scholarly journals Deep Wide-field Hα Images of the Magellanic Clouds

1999 ◽  
Vol 190 ◽  
pp. 95-96
Author(s):  
D. H. Morgan ◽  
Q. A. Parker ◽  
S. Phillipps
Keyword(s):  
Emission Line ◽  
Magellanic Clouds ◽  
Wide Area ◽  
Wide Field ◽  
Schmidt Telescope ◽  
Preliminary Results ◽  
Fine Grained ◽  
The Uk

A new Hα survey of the Magellanic Clouds which is being carried out on fine-grained Tech-Pan emulsion with the UK 1.2m Schmidt Telescope will have the best combination of depth and resolution of any that cover such a wide area in and around the Magellanic Clouds. Preliminary results show that the films will provide identifications of new emission-line stars and nebulae.

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