2001A&A...376...28R


Query : 2001A&A...376...28R

2001A&A...376...28R - Astronomy and Astrophysics, volume 376, 28-42 (2001/9-2)

Physical properties and small-scale structure of the Lyman-α forest: Inversion of the HE 1122-1628 UVES spectrum.

ROLLINDE E., PETITJEAN P. and PICHON C.

Abstract (from CDS):

We study the physical properties of the Lyman-α forest by applying the inversion method described by Pichon et al. (2001. A&A, in press) to the high resolution and high S/N ratio spectrum of the zem=2.40 quasar HE 1122-1628 obtained during Science Verification of UVES at the VLT. We compare the column densities obtained with the new fitting procedure with those derived using standard Voigt profile methods. The agreement is good and gives confidence in the new description of the Lyman-α forest as a continuous field as derived from our method. We show that the observed number density of lines with logN>13 and 14 is, respectively, 50 and 250 per unit redshift at z∼2. We study the physical state of the gas, neglecting peculiar velocities, assuming a relation between the overdensity and the temperature, T<T>(ρ(x)/ρ). There is an intrinsic degeneracy between the parameters β and <T>. We demonstrate that, at a fixed β, the temperature at mean density, <T>, can be uniquely extracted, however. While applying the method to HE 1122-1628, we conclude that for 0.2<β<0.3, 6000≪T><15000K at z∼2. We investigate the small-scale structure of strong absorption lines using the information derived from the Lyman-β, Lyman-γ and C IV profiles. Introducing the Lyman-β line in the fit allows us to reconstruct the density field up to ρ/ρ∼10 instead of 5 for the Lyman-α line only. The neutral hydrogen density is of the order of ∼2x10–9cm–3 and the CIV/H I ratio varies from about 0.001 to 0.01 within the complexes of total column density N(H I)∼1015cm–2. Such numbers are expected for photo-ionized gas of density nH∼10–4cm–3 and [C/H]~-2.5. There may be small velocity shifts (∼10km/s) between the peaks in the C IV and H I density profiles. Although the statistics is small, it seems that C IV/H I and nHI are anti-correlated. This could be a consequence of the high sensitivity of the C IV/H I ratio to temperature. The presence of associated O VI absorption, with a similar profile, confirms that the gas is photo-ionized and at a temperature of T∼105K.

Abstract Copyright:

Journal keyword(s): methods: data analysis - methods: N-body simulations - methods: statistical - galaxies: intergalactic medium - galaxies: quasars: absorption lines - cosmology: dark matter

VizieR on-line data: <Available at CDS (J/A+A/376/28): tablea1.dat>

CDS comments: Read HE 1122-1648 instead of HE 1122-1628

Simbad objects: 1

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Number of rows : 1
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 QSO B1122-168 QSO 11 24 42.8660012281 -17 05 17.386970324   16.5 16.5 16.1   ~ 124 1

Query : 2001A&A...376...28R

Basic data :
QSO B1122-168 -- Quasar
Origin of the objects types :

(Ref) Object type as listed in the reference "Ref"
(acronym) Object type linked to the acronym according to the original reference
() Anterior to 2007, before we can link the objet type to a reference, or given by the CDS team in some particular cases

Other object types:
QSO (2010A&A,QSO,...), Rad (MRC,NVSS,...), G (6dFGS,LEDA,...), IR (2MASS,2MASSI,...), * (Gaia), X (1RXS)
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
ICRS coord. (ep=J2000) :
11 24 42.8660012281 -17 05 17.386970324 (Optical) [ 0.0549 0.0390 90 ] A 2018yCat.1345....0G
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
FK4 coord. (ep=B1950 eq=1950) :
11 22 12.3488975399 -16 48 47.774703234 [ 0.0549 0.0390 90 ]
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
  • ra dec : right ascension and declination (unit and frame defined according to your Output Options)
    Grey values are increasing the original precision due to the computation of frame transformations
  • (wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
  • [error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
    position angle (in degrees North celestial pole to East)
  • quality : flag of quality
    • E ≥ 10"
    • D : 1-10" (and some old data)
    • C : 0.1-1"
    • B : 0.01-0.1" + 2MASS, Tyc
    • A : VLBI, Hipparcos
  • bibcode : bibcode of the coordinates reference
Gal coord. (ep=J2000) :
275.0175324217524 +41.0356892477998 [ 0.0549 0.0390 90 ]
Syntax of proper motions is : "pm-ra pm-dec [error ellipse] quality bibcode"
  • pm-ra : mu-ra*cos(dec) (expressed in the ICRS system in mas/yr)
  • pm-dec : mu-dec (expressed in the ICRS system in mas/yr)
  • [error ellipse] : error major axis and minor axis (in mas), orientation angle (in deg)
  • quality : flag of quality (A=best quality -> E=worst quality, {� } =unknown quality)
  • bibcode : bibcode of the proper motion reference
Proper motions mas/yr :
0.007 -0.189 [0.110 0.083 90] A 2018yCat.1345....0G
Syntax of radial velocity (or/and redshift) is : "value [error] (wavelength) quality bibcode"
  • value : radial velocity or/and redshift (Heliocentric frame) according to your Output Options
    (redshift may be not displayed if the data value is <0 and the database inside value is a radial velocity)
  • [error] : error of the corresponding value displayed before
  • (wavelength) : wavelength range of the measurement : Rad, mm, IR, Opt, UV, Xray, Gam or  '∼'(unknown)
  • quality : flag of quality ( A=best quality -> E=worst quality, {� } =unknown quality)
  • bibcode : bibcode of the value's origin
Radial velocity / Redshift / cz :
V(km/s) 251977 [~] / z(emission) 2.397 [~] / cz 718603 [~]
   (Opt) C 2017AJ....154..114O
Syntax of parallax is : 'value quality [error] bibcode'
  • value : parallax value
  • quality : flag of quality (A=best quality -> E=worst quality, {� } =unknown quality)
  • [error] : mean error
  • bibcode : bibcode of the parallax reference
Parallaxes (mas):
0.0065 [0.0811] A 2018yCat.1345....0G
Syntax of fluxes (or magnitudes) is : "filter-name (System) flux-value [error] quality MultVarFlags bibcode"
  • filter-name : U, B, V, R, I, G, J, H, K, u, g, r, i, z
  • (System) : may be AB (default is Vega)
  • flux-value : value of flux or magnitude
  • [error] : error value
  • quality : flag of quality of the flux value ( A=best quality -> E=worst quality, {� } =unknown quality)
  • MultVarFlags : Mult is zero or one char (J) for joined photometry ; Var can be zero or two chars (V[0-4])
  • bibcode : bibcode of the flux reference
Fluxes (7) :
B 16.5 [~] E 2010MNRAS.401.1151M
V 16.5 [~] E ~
R 16.1 [~] E 2010MNRAS.401.1151M
G 16.3704 [0.0015] C 2018yCat.1345....0G
J 15.254 [0.047] C 2003yCat.2246....0C
H 14.629 [0.044] C 2003yCat.2246....0C
K 13.809 [0.049] C 2003yCat.2246....0C
SIMBAD within arcmin
', {sourceSize:12, color:'#30a090'})); aladin.on('objectClicked', function(object) { var objName=object.data.MAIN_ID; aladin.showPopup(object.ra,object.dec,'',''+ objName+''); });" title="Show Simbad objects"> Overlay Simbad points in this preview
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within arcsec The VizieR photometry tool allows for easy visualization of photometry points extracted around the Simbad position from photometry-enabled catalogues in VizieR.
The search radius has to be specified by the user. It is currently limited to a maximum of 30 arcsec. It depends mostly on the precision or quality of the coordinates (SIMBAD and VizieR catalogs), the resolution of the images from which the sources were extracted, source extent, and source crowding.
Suggestions are: crowded field: 0.5 to 1.5 arcsec, 3 arcsec otherwise; uncertain coordinates (SIMBAD quality E or coordinates without reference): 5 to 30 arsec (risky!).
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Some important notes on this object about identifications and objects associations.
notes:


The link on the acronym of the identifiers give access to the information for this acronym in the dictionary of nomenclature.
Identifiers (37) :
An access of full data is available using the icon Vizier near the identifier of the catalogue

QSO B1122-168 2MASS J11244286-1705174 SDSS J112442.87-170517.5 [VV2000] J112442.8-170518
CTQ 299 2MASSI J1124428-170517 TIC 334849613 [VV2003] J112442.8-170518
CTS 299 MRC 1122-168 TXS 1122-168 [VV2006] J112442.8-170518
CTS R07.27 NVSS J112441-170508 VLSS J1124.6-1705 [VV2010] J112442.8-170518
6dFGS gJ112442.9-170517 PKS J1124-1705 WISE J112442.87-170517.3 [VV96] J112442.8-170518
HE 1122-1649 PMN J1124-1704 WISH B1122.1-1648 [VV98] J112442.8-170518
HE 1122-1648 QSO B1122-1648 WISH B1122.1-1648A Gaia DR2 3558587976212269056
HE 1122-1628 QSO B1122-1649 [BDW2002] q1122-1648
KODIAQ J112442-170517 QSO J1124-1705 [CL2003] HE 1122-1649 1
LEDA 2826720 1RXS J112442.0-170515 [HB93] 1122-168

References (124 between 1850 and 2021) (Total 124)
Simbad bibliographic survey began in 1850 for stars (at least bright stars) and in 1983 for all other objects (outside the solar system).
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Collections of Measurements


velocities : 10    PLX : 1    PM : 1   

   


External archives :

Archive data at HEASARC - High-Energy Astrophysics Science Archive Research Center

Data at NED - NASA/IPAC Extragalactic Database : QSO B1122-168

Link by name to the catalogue in VizieR :

2MASS J11244286-1705174 2MASSI J1124428-170517 NVSS J112441-170508 PKS J1124-1705 PMN J1124-1704
1RXS J112442.0-170515 SDSS J112442.87-170517.5 WISE J112442.87-170517.3 WISH B1122.1-1648 WISH B1122.1-1648A
Gaia DR2 3558587976212269056

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2021.08.02-17:08:46

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