The power spectrum of the flux distribution in the Lyman α forest of a large sample of UVES QSO absorption spectra (LUQAS)

The flux power spectra of the Lyman a forest from a sample of 27 quasi-stellar objects (QSOs) taken with the high-resolution Ultraviolet Echelle Spectrograph (UVES) on the Very Large Telescope (VLT) are presented. We find a similar fluctuation amplitude at the peak of the '3D' flux power spectrum at k ∼ 0.03 s km -1 as the study by Croft et al. (2002), in the same redshift range. The amplitude of the flux power spectrum increases with decreasing redshift if corrected for the increase in the mean flux level as expected if the evolution of the flux power spectrum is sensitive to the gravitational growth of matter density fluctuations. This is in agreement with the findings of McDonald et al. (2000) at larger redshift. The logarithmic slope of the '3D' flux power spectrum, P F (k), at large scales k < 0.03 s km -1 , is 1.4 ± 0.3, i.e. 0.3 shallower than that found by Croft et al. but consistent within the errors.

[1]  Edward J. Wollack,et al.  First-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Parameter Estimation Methodology , 2003, astro-ph/0302218.

[2]  Edward J. Wollack,et al.  First-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results , 2003, astro-ph/0302207.

[3]  Edward J. Wollack,et al.  First-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters , 2003, astro-ph/0302209.

[4]  P. Mcdonald.  Toward a Measurement of the Cosmological Geometry at z ~ 2: Predicting Lyα Forest Correlation in Three Dimensions and the Potential of Future Data Sets , 2001, astro-ph/0108064.

[5]  M. Viel,et al.  Dark energy effects on the Lyman α forest , 2002, astro-ph/0212241.

[6]  M. Viel,et al.  Galactic Winds in the Intergalactic Medium , 2002, astro-ph/0208418.

[7]  A. Aguirre,et al.  Metallicity of the Intergalactic Medium Using Pixel Statistics. I. Method , 2002, astro-ph/0207119.

[8]  R. Carswell,et al.  The physical properties of the Lyα forest at z > 1.5 , 2002, astro-ph/0205237.

[9]  D. Madgwick,et al.  New upper limit on the total neutrino mass from the 2 degree field galaxy redshift survey. , 2002, Physical review letters.

[10]  Cambridge,et al.  Modelling the IGM and the Lyα forest at high redshift from the dark matter distribution , 2002, astro-ph/0203418.

[11]  A. Hamilton,et al.  Matter power spectrum from the Lyman-alpha forest: myth or reality? , 2001, astro-ph/0111194.

[12]  S. Matarrese,et al.  The growth of structure in the intergalactic medium , 2001, astro-ph/0102220.

[13]  M. Zaldarriaga,et al.  Inferring the Linear Power Spectrum from the Lyα Forest , 2001, astro-ph/0111230.

[14]  M. Viel,et al.  Probing the intergalactic medium with the Lyα forest along multiple lines of sight to distant QSOs , 2001, astro-ph/0105233.

[15]  G. Bryan,et al.  Hydrodynamical simulations of the Lyα forest: data comparisons , 2001, astro-ph/0102367.

[16]  Max Tegmark,et al.  Constraints from the Lyα Forest Power Spectrum , 2000, The Astrophysical Journal.

[17]  E. Magnier,et al.  On Estimating the QSO Transmission Power Spectrum , 2000, astro-ph/0005049.

[18]  R. Croft,et al.  Toward a Precise Measurement of Matter Clustering: Lyα Forest Data at Redshifts 2-4 , 2000, astro-ph/0012324.

[19]  V. Narayanan,et al.  Constraints on the Mass of Warm Dark Matter Particles and the Shape of the Linear Power Spectrum from the Lyα Forest , 2000 .

[20]  P. Mcdonald,et al.  The Observed Probability Distribution Function, Power Spectrum, and Correlation Function of the Transmitted Flux in the Lyα Forest , 1999, astro-ph/9911196.

[21]  R. Davé,et al.  Cosmological Limits on the Neutrino Mass from the Lyα Forest , 1999, astro-ph/9903335.

[22]  M. Haehnelt,et al.  A first step towards a direct inversion of the Lyman forest in QSO spectra , 1998, astro-ph/9806109.

[23]  A. Banday,et al.  Evolution of large scale structure : from recombination to Garching : proceedings of the MPA-ESO Cosmology Conference : Garching, Germany, 2-7 August 1998 , 1999 .

[24]  R. Croft,et al.  The Power Spectrum of Mass Fluctuations Measured from the Lyα Forest at Redshift z = 2.5 , 1998, astro-ph/9809401.

[25]  R. Davé,et al.  The Low-Redshift Lyα Forest in Cold Dark Matter Cosmologies , 1998, astro-ph/9807177.

[26]  P. Mcdonald,et al.  Measuring the Cosmological Geometry from the Lyα Forest along Parallel Lines of Sight , 1998, astro-ph/9807137.

[27]  L. Hui.  Recovery of the Shape of the Mass Power Spectrum from the Lyα Forest , 1998, astro-ph/9807068.

[28]  M. Rauch.  THE LYMAN ALPHA FOREST IN THE SPECTRA OF QUASISTELLAR OBJECTS , 1998, astro-ph/9806286.

[29]  A. Leonard,et al.  P3M‐SPH simulations of the Lyα forest , 1998, astro-ph/9805119.

[30]  R. Croft,et al.  Recovery of the Power Spectrum of Mass Fluctuations from Observations of the Lyα Forest , 1997, astro-ph/9708018.

[31]  L. Hui,et al.  Probing the Universe with the Lyα forest — I. Hydrodynamics of the low-density intergalactic medium , 1997, astro-ph/9706219.

[32]  A. Davidsen,et al.  Evolution of Structure in the Intergalactic Medium and the Nature of the Lyα Forest , 1996, astro-ph/9611062.

[33]  D. Weinberg,et al.  The Lyman-Alpha Forest in the Cold Dark Matter Model , 1995, astro-ph/9509105.

[34]  R. Cen,et al.  The Lyα Forest from Gravitational Collapse in the Cold Dark Matter + Λ Model , 1995, astro-ph/9511013.

[35]  M. Norman,et al.  A Multispecies Model for Hydrogen and Helium Absorbers in Lyman-Alpha Forest Clouds , 1995, astro-ph/9508133.

[36]  Multifrequency observations of blazars. 5: Long-term millimeter, submillimeter, and infrared monitoring , 1994 .

[37]  R. Cen,et al.  Gravitational collapse of small scale structure as the origin of the Lyman alpha forest , 1994, astro-ph/9409017.

[38]  J. Peacock,et al.  Power spectrum analysis of one-dimensional redshift surveys , 1991 .

[39]  N. Kaiser.  Clustering in real space and in redshift space , 1987 .

[40]  B. Efron.  The jackknife, the bootstrap, and other resampling plans , 1987 .

[41]  J. Scargle.  Studies in astronomical time series analysis. II - Statistical aspects of spectral analysis of unevenly spaced data , 1982 .

[42]  N. Lomb.  Least-squares frequency analysis of unequally spaced data , 1976 .

[43]  Bruce A. Peterson,et al.  On the Density of Neutral Hydrogen in Intergalactic Space , 1965 .