Programs selected for UVES Science Verification  

• A Spectroscopic Survey of Intermediate Redshift QSOs(2.1<z<2.5)
• Abundance ratios of Extremely Metal Poor Stars from theHamburg-ESO Survey
• Chemical Abundances in LMC Clusters in a Wide Age Range
• Supernova 1987

Team: J. Bergeron , S. Cristiani, S. D'Odorico,V. Hill, T. Kim, F. Primas, M. Rauch, A. Renzini, P. Rosati Feedback from the users of SV data is an essentialaspect of the VLT Science Verification process. Users are warmly encouragedto send their comments to the VLT Program Scientist (arenzini@eso.org)and to inform him about the progress in the scientific analysis of thedata. A copy of the papers submitted for publication would also be appreciated,and will be treated confidentially if not otherwise indicated by the authors.  Back to UVES SV homepage

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A Spectroscopic Surveyof Intermediate Redshift QSOs

 

These observations are meant to be the first step towards a public surveyof QSO Absorbers which aims at creating a large and homogeneous datasetto allow the study of the intergalactic  medium and halos of high-zgalaxies at z = 0-3.

* thermal history of the IGM, intensity and shape of the UV background

* Redshift evolution of matter distribution

* Kinematics and metal-enrichment in the IGM and halos of high-z galaxies

The 3 highlighted QSOs were observed with a slit of  0.8" (red)and 0.9" (blue) when the seeing was good, and 1" when the seeing was mediocre(R=50000-43000). A combination of the two Dichroic settings Dic 1(B346nm+ R580nm) and Dic2 (B347nm + R860nm) provided  the whole spectralrange 300nm-1000nm. Depending on the seeing conditions, the binning ofthe CCD was 2x2 or 2x1, and exposure times were between 1h and 1h30.

Q 1101-264:
Dic 1 (B346nm + R580mn) = 6h00
Dic 2 (B437nm + R860mn) = 6h00

HE 1122-1648
Dic 1 (B346nm + R580mn) = 7h20
Dic 2 (B437nm + R860mn) = 6h30   (1h00and 2x1h30 are low counts because of poor seeing)

HE 1347-2457
Dic 2 (B437nm + R860mn) = 4h00

The following  S/N arise from a quick-look analysis of the dataobtained for  Q1101-264 and HE1122-1648. These two QSOs have similarflux of 2 x 10^-15 erg s^-1 cm^-2 A^-1 at 3200 A (from IUE, HST and optical data). No binning/smoothing has been applied for the estimate ofthe S/N which is given per spectral pixel of the extracted spectra.

Lambda     S/N
 3150      15      
 3400      50
 3800-6000 60-80
 
 

Examples of the Quick-lookreduced data

 Access here the quick-lookreduced spectra or the fullraw data.

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Abundance Ratiosof Extremely Metal Poor stars

The known objects closest to pristine, unevolvedmatter are the Extremely Metal-Poor Stars in our Milky-Way, which havemetallicities less than 1/1000th of solar.The detailed chemical contentof these stars yields insight on early Galactic evolution and nucleosynthesis:

* primordial light elements abundances (Li,Be)

* elemental yields of early SNII and their massfunction

* nucleosynthetic products of first AGBs

* efficiency of mixing process in the early Galaxy

Candidates metal-poor Turnoff stars fromHE Survey

Identification from Christlieb 2000, "Thestellar content of the Hambourg-ESO Objective-Prism Survey", PhD Thesis *)The metallicity scale was brought tomach that of Beers et al. 1999   The 2 highlighted stars from the Hamburg-ESO wereobserved in Dichroic mode (Dic2 B470nm + R785nm)  with slit of 1"corresponding  to R=45,000, and giving a spectral coverage: 409nm-531nm+ 594nm-975nm.
The S/N stated  is an aproximate value perspectral pixel of the extracted spectra, around 520nm
 

HE 1353-2735^*
Dic 2 (B470nm + R785nm) 2x1h30             S/N 50,50
 
HE 1303-2708
Dic 2 (B470nm + R785nm) 2x1h30 +1h^** +0h45  S/N 62,tbd,tbd,tbd

Notes:
*     thisstar turned out to be most likely a double-lined binary
**  the blue image ofthis exposure was lost because of a technical problem

Other extremely metal-poor stars

n addition to these new metal-poor candidates,G64-12, a well-known extremely metal poor star was observed at very highS/N to provide the community with a  "template spectrum" of a verymetal poor star (test of models, ...), all the way to the UV.
The observations were done with a 0.8" slit (R=60,000)and 2 Dichroic modes (Dic1 B346nm + R580nm and Dic1 B346 + R860nm) givinga total coverage : 300nm-390nm +480nm-1000nm.

G 64-12
Dic 1 (B346nm + R580nm) 2x1h30   S/N 100,115 @335nm
                                     350,370@510nm
Dic 1 (B346nm + R860nm) 2x1h30   S/N  85,105 @335nm
                                     270,280@700nm
 

Examples of the Quick-lookreduced data

  Access here the quick-lookreduced spectra or the fullraw data.

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Chemical Abundancesin LMC Clusters in a Wide Age Range

The star formation and chemical enrichement historyof the Large Magellanic Clouds can be investigated using stellar clustersin a wide age range as tracers. In addition, the knowledge of the chemicalcomposition of stars in stellar clusters in the MCs can be used as stellarphysics tools : ages of the clusters, evolutionary tracks at low metallicities,...Red Giants in 4 LMC Clusters were targeted(16.5< V < 17) for a detailed abundance analysis.

9 Giants were observed in the 4 highlighted clusterswith the R580nm setting and a slit  of 1.0" to 1.2" (depending onseeing ) corresponding to R=40,000 to 45,000, and giving a spectral coverage:480nm-680nm.
The S/N stated  is an approximate valueper spectral pixel of the extracted spectra, around 600nm

NGC 1866 (IdentificationBrocato et al. 1989)
R580   1h30 star444   S/N 70
R580   1h00 star1653  S/N 80
R580 2x1h00 star 867  S/N 23,25

NGC 1978(Identification Loyd & Evans 1980)
R580 2x1h15 star LE8  S/N 48,48
R580 2x1h15 star LE9  S/N 47,42
Dic 2 (B437nm + R860nm) 2 x1h15 star LE9

ESO 121 (Identification Mateo 1986)
R580 2x1h30 star M313 S/N 23,28
R580 2x1h15 star M167 S/N 40,40

NGC 2210 (IdentificationBrocato et al. 1996)
R580   1h40 star4364  S/N 50 + star 110 on the same slit
R580   1h30 star4793  S/N 50
 

Examples of the Quick-lookreduced data

  Access here the quick-lookreduced spectra or the fullraw data.

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Supernovae 1987a

2 spectra of SN87a were obtained with the R580nmand Dic1 (B346nm + R580nm) settings providing a spectral coverage 300nm-390nm+ 480nm-680nm .
 
SN87a
R580 30mn
Dic1 1h00 Access here the quick-lookreduced spectra or the fullraw data.

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Full night-by-night Logs