Objective Prism Plates Research Articles

The large, bright QSO survey. V - QSOs in three southern fields

This is the fifth and final paper in a series reporting the results of a program aimed at selecting ∼1000 QSOs brighter than B J ⇒ 18.75 using machine-scanned direct and objective-prism plates from the UK Schmidt Telescope. The plate material is scanned at the Automated Plate Measuring facility. The candidate list is derived using a number of complementary selection algorithms ranging from traditional criteria, such as the presence of strong emission features, to criteria designed to select objects whose objective-prism spectra cannot be classified as normal stars, although they may possess no obvious QSO-like features. Results from three UK Schmidt Telescpe fileds in which 200 QSOs have been found are presented

The case low-dispersion northern sky survey. XII - A region in southern Canes Venatici

view Abstract Citations (18) References (40) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Case Low-Dispersion Northern Sky Survey. XII. A Region in Southern Canes Venatici Pesch, Peter ; Sanduleak, N. ; Stephenson, C. B. Abstract Positions, estimated magnitudes, and finding charts (when necessary) are provided for 194 blue and/or emission-line galaxies, 15 H II regions in seven galaxies, 157 unresolved blue and/or emission-line objects, including QSO candidates, and 32 known and suspected blue stars in a 107 deg^2^ region in Canes Venatici encompassed by 12_h_15_m_ < R.A. < 14_h_00_m_ and +33^deg^<Decl.<+38^deg^(1950). The objects, whose blue magnitudes are mostly within the range 15-18, were identified on low- dispersion objective-prism plates taken with the Burrell Schmidt telescope at Kitt Peak. Publication: The Astrophysical Journal Supplement Series Pub Date: August 1991 DOI: 10.1086/191589 Bibcode: 1991ApJS...76.1043P Keywords: Blue Stars; Faint Objects; Northern Sky; Quasars; Sky Surveys (Astronomy); Emission Spectra; H Ii Regions; Line Spectra; Schmidt Telescopes; Stellar Magnitude; Astronomy; GALAXIES: GENERAL; QUASARS; STARS: FAINT BLUE full text sources ADS | data products SIMBAD (408) NED (366) Related Materials (16) Erratum: 1996ApJS..102R.435P Erratum: 1996ApJS..103Q.513P Part 1: 1983ApJS...51..171P Part 2: 1984ApJS...55..517S Part 3: 1986ApJS...60..543P Part 4: 1987ApJS...63..809S Part 5: 1988ApJS...66..297P Part 6: 1988ApJS...66..309S Part 7: 1988ApJS...66..387S Part 8: 1989ApJS...70..163P Part 9: 1989ApJS...70..173S Part 10: 1989ApJS...71..549P Part 11: 1990ApJS...72..291S Part 13: 1992ApJS...82..471S Part 14: 1993ApJS...86..453M Part 15: 1995ApJS...98...41P

The large, bright QSO survey. III - QSOs in six equatorial fields

This is the fourth paper in a series aimed at selecting about 1000 QSOs brighter than B(J) about 18.7 using machine-scanned direct and objective-prism plates from the UK Schmidt Telescope. The plate material is scanned at the Automated Plate Measuring facility. The candidate list is derived using a number of complementary selection algorithms ranging from 'traditional' criteria, such as the presence of strong emission features, to criteria designed to select objects whose objective-prism spectra cannot be classified as normal stars, although they may possess no obvious QSO-like features. Follow-up spectroscopy at the Multiple Mirror Telescope is used to classify each candidate. This paper presents results from the two final UK Schmidt Telescope equatorial fields in which 125 QSOs have been found as well as the detection of an additional 11 QSOs in the 0000+0000 field presented in the second paper in this series. Coordinates, magnitudes, redshifts and spectra of moderate resolution, and signal-to-noise ratio for all 136 QSOs are presented as well as for eight additional extragalactic objects which fail to meet the absolute magnitude criterion as QSOs. 9 refs.

MRSP?The muenster redshift project. Astrometric determination of the reference point for wavelength measurements on low-dispersion objective prism plates

The zero point of galaxy redshifts measured from objective prism plates (dispersion 246 nm/mm at Hγ) as part of the Muenster Redshift Project (MRSP) is obtained through transformation of object positions from the corresponding direct plate. Approximately 1000 G-type stars, classified automatically, are used. On the direct plate, positions are obtained from intensity-weighted first moments. On the objective prism plate, object positions are give through the CaII-break and marginal fits to the unwidened spectra. The transformation equations include quadratic terms in the direction of dispersion. The inclusion of third-order and colour terms is discussed. The mean residuals are approximately 0".33 (5 μm on the plate), corresponding to a redshift error of about 700 km/s at z=0.0. This error results mainly from the uncertainty in locating the CaII-break in the low-dispersion spectra. Radial velocities are obtained from the difference between the expected and the measured positions of the CaII-break in the galaxy spectra.

The vertical structure of our galaxy. I - Methods of quantitative objective prism spectroscopy

view Abstract Citations (14) References (25) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Vertical Structure of our Galaxy. I. Methods of Quantitative Objective Prism Spectroscopy Rose, James A. Abstract The methods employed to determine the spectral types and log g and Fe/H values for Galactic F-K stars in the vertical-structure investigation of Rose and Agustinho (1991) are described in detail. IIaO objective-prism plates obtained with the Curtis Schmidt telescope at CTIO using a 10-deg prism and a 135-A FWHM interference filter centered at 408 nm are digitized, and three spectral indices defined by Rose (1984) are measured and used to calculate the desired parameters. Results from tests of the accuracy of this method are presented, and it is shown that reliable separation of G dwarfs from G giants/subgiants is possible down to B = 13. Publication: The Astronomical Journal Pub Date: March 1991 DOI: 10.1086/115738 Bibcode: 1991AJ....101..937R Keywords: Astronomical Spectroscopy; G Stars; Galactic Structure; Milky Way Galaxy; Astronomical Photography; Dwarf Stars; Giant Stars; Metallicity; Spectrum Analysis; Astrophysics; GALAXIES: THE GALAXY; STARS: ABUNDANCES full text sources ADS | data products SIMBAD (87) Related Materials (1) Part 2: 1991AJ....101..950R

Objective Determination of the Large-scale Distribution of Galaxies

AbstractObservations of the large-scale organisation of matter in the Universe are of great importance in present day astronomy. In the visible part of the spectrum such observations are mainly of the distribution of galaxies on the plane of the sky.Direct and objective prism plates obtained using large Schmidt telescopes form the bulk of the material used. The direct plates provide the observations from which the surface distribution of galaxies may be determined and the prism plates and FLAIR, via redshifts, yield extragalactic distances and hence the three dimensional distribution of galaxies.For large-scale surveys the measuring machines used need to be multi-purpose and fast such as COSMOS and SUPER-COSMOS at the Royal Observatory Edinburgh. More specific programs can make use of smaller, slower machines such as iris photometers and microdensitometers.The method of analysing the data produced rely on seeking density enhancements in the general field of galaxies for cluster detection or using correlation techniques for analysis of the galaxy distribution.A description is given of a southern sky catalogue containing 109 objects recently completed and an outline of some of the extragalactic projects underway using this large body of data.

Further Observations of the Emission-Line Stars in the Open Cluster NGC 663

view Abstract Citations (14) References (6) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Further Observations of the Emission-Line Stars in the Open Cluster NGC 663 Sanduleak, N. Abstract Long-term monitoring of NGC 663 on objective-prism plates confirms the presence of 24 Hα-emission-line stars, half of which show evidence of marked emission-line variability on a timescale of years to decades. Publication: The Astronomical Journal Pub Date: October 1990 DOI: 10.1086/115589 Bibcode: 1990AJ....100.1239S Keywords: STARS: EMISSION-LINE; CLUSTERS: OPEN full text sources ADS | data products SIMBAD (26)

Objective prism survey of QSO candidates in the field centered at 00 H00 M + 00° 00' paper v. discussion of survey results

This is the last in the series of papers on our visual search for QSO candidates, using low dispersion objective prism plates obtained with the UK Schmidt Telescope. We discuss and summarize some results at the current stage of this project. As a supplement to the Q ⩾ 4 candidates published in the previous papers we give in this paper the subset of Q = 3 candidates which have ultraviolet excess. Our survey may suffer from many types of contamination since any object was considered as a QSO candidate if we could not unambiguously classify it as a star, a galaxy or some other known type of object. Despite this, many of our candidates are interesting enough for follow-up slit spectroscopy. This will also provide us with useful information for improving our selection criteria.

The off-focus photograph technique for low dispersion spectra

We have developed a photograph filtering technique to search for QSOs with objective prism plates. After off-focus reproduction, the signal-to-noise ratio increases and some spectral lines in the prism spectra may be recognized by eye against the noise. Principle of this technique is discussed.

TWO NEW EXTREMELY LUMINOUS QSOS

ABSTRACT have been identified on objective-prism plates taken for the Case Low-Dispersion Northern Sky Survey.

A New Planetary Nebula

The object (α1950 = 18h04m.3; δ1950 = −8o56!4) was discovered in a 103a-E+RG 1 objective prism plate taken with the 92/67-cm Schmidt telescope of the Astrophysical Observatory of Asiago (Italy). It presents only the Hα emission and no stellar continuum; following Kohoutek (1965, 1969, 1972) it is a bona fide planetary nebula. This classification is confirmed by the appearance of the object in the red and infrared plates of the Near Infrared Photographic Survey of the galactic plane (Sabbadin, 1986): it is quite bright in the red plate and almost invisible in the infrared one.

The APM QSO Survey: Description and Status Report

The APM QSO survey is a quantitative survey aimed at finding a large sample (∼ 1000) of QSOs using broadly-based selection criteria applied to machine-scanned UK Schmidt Telescope direct and objective-prism plates. The survey is currently entering its third year and, as of August 1988, the sample consists of ∼ 700 QSOs with mJ ≥ 18.75 in the range 0.2 ≤ z ≤ 3.3. Preliminary analysis suggests that the sample is relatively free of the selection effects endemic to most QSO surveys based on slitless spectroscopy.

Is NGC 2242 a New Planetary Nebula?

An interesting object was found on the IIIaJ objective prism plate SP1270, taken on Jan. 12.6 UT, 1983 with the Beijing Observatory 60/90-cm Schmidt telescope plus 5°.3 objective prism with a dispersion of 580 A/mm at Hγ. The emission lines [O III]λλ4959+5007 and Hβ were extremely strong. The lines Hγ—Hδ and [O II]λ3727, all in emission, were broad and conspicuous. Two prominent emissions were tentatively identified as He II λ4686 and He II λ4542. Of all these lines none showed any noticeable redshift. It belongs to the Galaxy. The overall spectrum looked like that of a planetary nebula. But on the POSS overlay this object was designated as RNGC 2242 and ZWG 204.005. It was listed as a galaxy either in ZWG, or in A Master List of Nonstellar Optical Astronomical Objects, but it was absent from any previous catalogues of the planetary nebula.

The Case low-dispersion northern sky survey. VII - Late-type stars

view Abstract Citations (47) References (7) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Case Low-Dispersion Northern Sky Survey. VII. Late-Type Stars Sanduleak, N. ; Pesch, Peter Abstract Positions, approximate red magnitudes, and finding charts are provided for 132 faint red stars that show definite or strongly suspected carbon or late M-type spectra. These stars, with apparent red magnitudes ranging from 9 to 17, lie in a roughly 1000 square degree area of sky at high northern Galactic latitudes defined by the approximate boundaries 8h15m < R.A. <17h30m and +29° < decl. < +38°. They were identified on low-dispersion objective-prism plates taken with the Burrell Schmidt telescope at Kitt Peak. Publication: The Astrophysical Journal Supplement Series Pub Date: April 1988 DOI: 10.1086/191262 Bibcode: 1988ApJS...66..387S Keywords: Carbon Stars; Late Stars; Northern Sky; Sky Surveys (Astronomy); Stellar Magnitude; Stellar Spectra; Faint Objects; Halos; M Stars; Astronomy; STARS: CARBON; STARS: LATE-TYPE; STARS: SPECTRAL CLASSIFICATION full text sources ADS | data products SIMBAD (131) CDS (2) Related Materials (16) Catalog: 1994yCat..20660387S Erratum: 1996ApJS..103R.513P Part 1: 1983ApJS...51..171P Part 2: 1984ApJS...55..517S Part 3: 1986ApJS...60..543P Part 4: 1987ApJS...63..809S Part 5: 1988ApJS...66..297P Part 6: 1988ApJS...66..309S Part 8: 1989ApJS...70..163P Part 9: 1989ApJS...70..173S Part 10: 1989ApJS...71..549P Part 11: 1990ApJS...72..291S Part 12: 1991ApJS...76.1043P Part 13: 1992ApJS...82..471S Part 14: 1993ApJS...86..453M Part 15: 1995ApJS...98...41P

A Search for Galactic Carbon Stars

The carbon star is one of the best probes for the galactic study; (1)it is intrinsically bright (Mbol = − 2 to − 6) especially in the red and infrared wavelength regions,(2)it has spectral features readily detectable on objective prism plates due to their strong carbon molecular bands,(3)it is an evolved star distributed abundantly (∼1 star per square degree) along the galactic plane.We can detect it in the Galaxy up to several kpc from the sun on objective prism plates of the Schmidt telescope.We have been making survey observations of faint cool carbon stars using the Kiso 105-cm Schmidt telescope. Kodak IN and 103aF plates are respectively taken behind the 4-degree objective prism (700 Åmm−1 at Hα) for the detection and for the spectral classification. V-band plates are utilized to obtain the position and the brightness of the stars detected.The survey areas are distributed along the northern galactic plane. Seven fields in the Cassiopeia region (l = 115° to 133° and eight fields in the Taurus-Auriga-Gemini region (i = 170° to 188°) have been observed and processed up to now (Maehara and Soyano 1987a,b).

MRSP - The Muenster Redshift Project

ESO/SRC-J-Atlas plates (film copies) and film copies of UK-Schmidt objective prism J-plates (dispersion 246nm/mm at Hγ) were scanned with the microdensitometer PDS 2020 GM and reduced automatically with the software package ADAS developed at the Astronomical Institute of Muenster University. In a single field (30 square degrees) near the South Galactic Pole 150 000 objects are found up to the limiting magnitude Stars and galaxies are separated. Algorithms for quasar search among the star-like objects are applied and radial velocities determined from the identified emission lines. Follow-up observations with the ESO 3.6m telescope show fair agreement between the redshifts determined from the objective prism plate and from the slit spectra.

An automated survey for gravitational lenses

A new optical technique for surveying large numbers of quasars for evidence of gravitational lensing is described. Using the Automated Plate Measuring Facility at Cambridge to scan broadband direct and objective-prism plates, hundreds of thousands of objects can be examined to find quasar candidates with multiple image structures. The technique is effective for separations greater than about two arcseconds, and allows the probability of detecting a lens of specified magnitude, component magnitude difference, and component separation to be precisely calculated. Tables are given that quantify the probability of detection of multiply imaged quasars. When combined with the large numbers of quasars surveyed, specific theoretical predictions of the frequency of lensing can be directly tested. The results of a survey of 2500 quasars with magnitudes in the range of 17-20 covering 130 sq deg of sky are described. Significant new limits can be put on the numbers of gravitationally lensed quasars with wide image separations. These limits enable some calculations of the distribution of mass in the universe to be undertaken. In particular, limits can be placed on the numbers of cosmic strings in the universe. 21 references.

Quasar Clustering at Intermediate Redshifts

This paper summarizes recent results from a study of quasar clustering based on a survey of U.K. Schmidt objective prism plates using the Automatic Plate Measuring facility at Cambridge. New procedures have been developed to detect quasars, eliminate contamination and measure accurate redshifts from the (see Drinkwater, M.J. 1987. Mon. Not. R. astr. soc., submitted). The redshift identifications are 90% reliable with an error (rms) of Δz = ±0.019 for quasars to a limiting magnitude of Bj = 19.5. Some 600 quasars from 6 U.K. Schmidt fields in the redshift range 1.8 &lt; z &lt; 2.6 have been analysed for weak clustering using power spectrum analysis (Webster, A. 1976. Mon. Not. R. astr. soc.175, 61). Plots of the statistic Q′ for 2-D and 3-D (4 fields only) projections of the data are given in the figure below. The ±1σ expectation values of Q′ calaulated for random simulations of the data (including non-uniform redshift selection and plate sensitivity) are indicated by vertical bars.

PROBABLE NEW HALO STARS TOWARD L =310, B =+30.

ABSTRACT Eighty-three probable halo giants have been identified in Stock's recently published objective-prism survey of an intermediate galactic latitude field. Approximate radial velocities derived from the objective-prism plates yield a velocity dispersion of 98±8 km sec-1 for these stars.

An H-alpha emission-line survey of the rho Ophiuchi dark cloud complex

Our analysis of two H-alpha objective-prism plates covering about 40 square degrees and including most of the nearby rho Ophiuchi cloud complex is presented. These data provide a high-resolution, completely sampled survey of stars in the T Tauri phase of pre-main-sequence evolution in the lower-extinction regions of the dark cloud. Detailed finder charts and accurate positions for 86 sources of definite or probable H-alpha emission are presented, making this survey useful for future studies of global star formation in the rho Oph clouds. In addition, the first Herbig-Haro object candidates in this area has been found. The correspondence of the emission-line stars with the densest molecular gas and known T Tauri stars, X-ray sources, and IRAS point sources suggest that most of the stars in our sample are indeed young stellar objects. Comparing the number of these objects in the main cloud core with the total number of association members suggests that about 25 percent of the association members are currently observed in the T Tauri phase of evolution near the surface of the cloud. The preponderance of emission-line stars in the western regions of the complex may imply a critical density necessary for star formation to occur or perhapsmore » an actual progression of star formation through the complex. 27 references.« less