scholarly journals Hamburg/SAO Survey of Emission-Line Galaxies

1998 ◽  
Vol 179 ◽  
pp. 299-301 ◽  
Author(s):  
V. Lipovetsky ◽  
D. Engels ◽  
A. Ugryumov ◽  
U. Hopp ◽  
G. Richter ◽  
...  
Keyword(s):  
Emission Line ◽  
Special Astrophysical Observatory ◽  
Byurakan Survey ◽  
Large Sample ◽  
Sky Survey ◽  
First Results ◽  
Compact Galaxies ◽  
Emission Line Galaxies ◽  
Low Dispersion

We present first results of the Hamburg/SAO Survey of emission-line galaxies (hereafter HSS, SAO—Special Astrophysical Observatory, Russia) initiated to search for extremely metal-deficient (Z < Z⊙/10) galaxies and to create a large sample of Blue Compact Galaxies (BCG). This “Northern BCG Sample,” will be assembled by merging the HSS with samples from the Second Byurakan Survey (SBS) (Stepanian et al. 1987) and the Case Low-Dispersion Northern Sky Survey (Pesch et al. 1991).

scholarly journals The Second Byurakan Spectral Sky Survey

1987 ◽  
Vol 121 ◽  
pp. 25-35
Author(s):  
B.E. Markarian ◽  
J.A. Stepanian ◽  
L. K. Erastova
Keyword(s):  
Observational Data ◽  
Surface Density ◽  
Luminosity Function ◽  
Special Astrophysical Observatory ◽  
Schmidt Telescope ◽  
Byurakan Survey ◽  
First Byurakan Survey ◽  
Sky Survey ◽  
Spectral Survey ◽  
Low Dispersion

The method of the Second Spectral Survey carried out with the Byurakan 1-m Schmidt telescope is discussed. The limiting magnitude is fainter in comparison with the First Byurakan Survey at about 2–3m.The results of low dispersion (500 objects) and slit spectroscopy (300 objects) based on observations with the 6-m telescope of Special Astrophysical Observatory for four fields of the Second Survey are presented.The luminosity function of faint UV galaxies is discussed. The completeness of AGN of the Second Survey and their surface and space densities are also estimated. The surface density of QSO and ELG is estimated and these data are compared with the results of other surveys.New observational data obtained with the 6-m telescope are compared with the new data of different deep surveys carried out during last years.

scholarly journals Comparison of ELG and UV Galaxies from the SBS Survey

2002 ◽  
Vol 184 ◽  
pp. 94-96
Author(s):  
M. V. Gyulzadian
Keyword(s):  
Emission Line ◽  
Diagnostic Method ◽  
Special Astrophysical Observatory ◽  
Physical Parameters ◽  
Great Care ◽  
Byurakan Survey ◽  
Hii Region ◽  
Uv Excess ◽  
Emission Line Galaxies ◽  
Ambiguous Objects

AbstractIn this paper we compare the results of spectrophotometric observations for more then 40 emission line galaxies (ELG) without UV-excess and 70 galaxies with UV-excess (UV-galaxies) from the Second Byurakan Survey (SBS) carried out with the scanner on the 6-m telescope of the Special Astrophysical Observatory. The comparison was aimed to answer the questions: are there any essential differences between these two types of galaxies? And what is the fraction of AGN among ELG and UV-galaxies? To answer this question we have investigated some physical parameters. Great care was taken in classifying the spectra of these galaxies as “HII region-like or “AGN-like” using a new diagnostic method for emission-line galaxies (Rola et al.). We find that 14% of emission line galaxies (ELG) have Sy2 and LINER-like spectra. The transition or ambiguous objects among them comprise 20%. The fraction of LINER-like and Sy2 objects among UV-galaxies is 21% while that of the transition or ambiguous objects in UV-galaxies is 28%. From SBS galaxies, 18% are Sy2s and LINER-like galaxies.

scholarly journals OMEGA: OSIRIS Mapping of Emission-Line Galaxies in A901/2

2014 ◽  
Vol 10 (S309) ◽  
pp. 171-174
Author(s):  
Bruno Rodríguez del Pino ◽  
Ana L. Chies-Santos ◽  
Alfonso Aragón-Salamanca ◽  
Steven P. Bamford ◽  
Meghan E. Gray
Keyword(s):  
Star Formation ◽  
Emission Line ◽  
Large Sample ◽  
Spatially Resolved ◽  
La Palma ◽  
First Results ◽  
Multi Wavelength ◽  
Emission Line Galaxies

AbstractThis work presents the first results from an ESO Large Programme carried out using the OSIRIS instrument on the 10m GTC telescope (La Palma). We have observed a large sample of galaxies in the region of the Abell 901/902 system (z∼0.165) which has been extensively studied as part of the STAGES project. We have obtained spectrally and spatially resolved H-alpha and [NII] emission maps for a very large sample of galaxies covering a broad range of environments. The new data are combined with extensive multi-wavelength observations which include HST, COMBO-17, Spitzer, Galex and XMM imaging to study star formation and AGN activity as a function of environment and galaxy properties such as luminosity, mass and morphology. The ultimate goal is to understand, in detail, the effect of the environment on star formation and AGN activity.

scholarly journals Quasi-stellar objects acting as potential strong gravitational lenses in the SDSS-III BOSS survey

2019 ◽  
Vol 625 ◽  
pp. A56 ◽  
Author(s):  
Romain A. Meyer ◽  
Timothée Delubac ◽  
Jean-Paul Kneib ◽  
Frédéric Courbin
Keyword(s):  
Emission Line ◽  
Sloan Digital Sky Survey ◽  
Emission Lines ◽  
Gravitational Lenses ◽  
Stellar Objects ◽  
Sky Survey ◽  
Quasi Stellar Objects ◽  
Unique Approach ◽  
Algorithmic Search ◽  
Emission Line Galaxies

We present a sample of 12 quasi-stellar objects (QSOs) that potentially act as strong gravitational lenses on background emission line galaxies (ELG) or Lyman-α emitters (LAEs) selected through a systematic search of the 297 301 QSOs in the Sloan Digital Sky Survey (SDSS)-III Data Release 12. Candidates were identified by looking for compound spectra, where emission lines at a redshift larger than that of the quasar can be identified in the residuals after a QSO spectral template is subtracted from the observed spectra. The narrow diameter of BOSS fibers (2″) then ensures that the object responsible for the additional emission lines must lie close to the line of sight of the QSO and hence provides a high probability of lensing. Among the 12 candidates identified, nine have definite evidence for the presence of a background ELG identified by at least four higher-redshift nebular emission lines. The remaining three probable candidates present a strong asymmetrical emission line attributed to a background Lyman-α emitter (LAE). The QSO-ELG (QSO-LAE) lens candidates have QSO lens redshifts in the range 0.24 ≲ zQSO ≲ 0.66 (0.75 ≲ zQSO ≲ 1.23 ) and background galaxy redshifts in the range 0.48 ≲ zS, ELG ≲ 0.94 (2.17 ≲ zS, LAE ≲ 4.48). We show that the algorithmic search is complete at > 90% for QSO-ELG systems, whereas it falls at 40−60% for QSO-LAE, depending on the redshift of the source. Upon confirmation of the lensing nature of the systems, this sample may quadruple the number of known QSOs acting as strong lenses. We have determined the completeness of our search, which allows future studies to compute lensing probabilities of galaxies by QSOs and differentiate between different QSO models. Future imaging of the full sample and lens modelling offers a unique approach to study and constrain key properties of QSOs.

scholarly journals The Case Low-Dispersion Northern Sky Survey

1984 ◽  
Vol 78 ◽  
pp. 53-56
Author(s):  
Peter Pesch ◽  
N. Sanduleak
Keyword(s):  
Main Sequence ◽  
Stellar Objects ◽  
Threshold Detection ◽  
Rr Lyrae ◽  
Horizontal Branch Stars ◽  
Sky Survey ◽  
Uv Excess ◽  
Emission Line Galaxies ◽  
Low Dispersion ◽  
New Location

AbstractThe Burrell Schmidt-type telescope of the Warner and Swasey Observatory in its new location on Kitt Peak in Arizona is being used for a spectroscopic survey of the region b > +30°. and δ > +30°. The plates, which cover 5° x 5° are taken with the 1.8 prism which provides a dispersion of 1350 Å mm-1 at Hγ. Eastman Kodak IIIa-J plates, baked in forming gas, are used without filter to cover the spectral range 3300 to 5350 Å. The exposure times of 75 minutes reach a limiting blue magnitude of ~ 18.0 for threshold detection of an unwidened stellar continuum. The categories of objects which are being catalogued are blue and/or emission-line galaxies, probable HII regions, blue and/or mission-line stellar objects, known and probable blue stars, main-sequence late B and A-type stars, suspected field horizontal-branch stars of types A and F including RR Lyrae variables, suspected F and G-type subdwarfs showing a UV excess, faint carbon and late M suspected halo giants, and peculiar objects.

scholarly journals Byurakan Surveys: Density of Bright AGN

2002 ◽  
Vol 184 ◽  
pp. 92-93
Author(s):  
L.K. Erastova
Keyword(s):  
Emission Line ◽  
Active Galaxies ◽  
Host Galaxies ◽  
Stellar Objects ◽  
Morphological Criteria ◽  
Emission Line Galaxies ◽  
Low Dispersion

It is clear now that morphological criteria don’t divide galaxies from QSOs. Many galaxies are stellar-like objects and, conversely, quasars have host galaxies of various luminosities. For instance, two objects - SBS 1120+586A and SBS 1123+598 - absolutely do not differ from stars on the charts of the POSS and were classified as BSO-type. But they turned out to be galaxies with moderate luminosities (Markarian et al. 1988). Erastova (2000) produced a list of stellar-like galaxies from the SBS. Out of 339 KUV objects, 107 (31.6%) are emission-line galaxies of various luminosities (Darling & Wegner 1996). A considerable number of active galaxies appear among CSO - Case stellar objects. Conversely, objects having extended images on low-dispersion spectral plates turned out to be QSOs. SBS 1520+530 is a gravitationally lensed QSO with z=1.855 and on our low-dispersion plates appears as a galaxy (Chavushyan et al., 1997).

scholarly journals TheHubble Space TelescopeACS Grism Parallel Survey. II. First Results and a Catalog of Faint Emission-Line Galaxies atz ≤ 1.6

2005 ◽  
Vol 130 (4) ◽  
pp. 1324-1336 ◽  
Author(s):  
Igor Drozdovsky ◽  
Lin Yan ◽  
Hsiao-Wen Chen ◽  
Daniel Stern ◽  
Robert Kennicutt, Jr. ◽  
...  
Keyword(s):  
Emission Line ◽  
First Results ◽  
Emission Line Galaxies
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