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correcting for intergalactic gas Telfer, Zheng, Kriss et al. derived a composite SED using 332 HST- FOS spectra of 183 quasars they corrected for the Lyman valley –each spectrum was divided by the appropriate Transmission function –comparison with SLOAN confirms strategy: coincidence of the discontinuities with position of Ly and Ly rest F HST/SDSS Telfer et al SLOAN ratio: HST/SDSS HST Ly Ly main
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The far-UV break in The far-UV break in quasar SEDs, dust?quasar SEDs, dust?
Luc BinetteLuc BinetteSinhue Haro-CorzoSinhue Haro-CorzoYair KrongoldYair KrongoldAnja AndersenAnja Andersen
Xi’an, October 2006Xi’an, October 2006
Note: the text accompanying this talk can
Note: the text accompanying this talk can
be found at astro-ph/0611011
be found at astro-ph/0611011
correcting for intergalactic gas• Telfer, Zheng , Kriss et
al. derived a composite SED using 332 HST-FOS spectra of 183 quasars
• they corrected for the Lyman valley– each spectrum was
divided by the appropriate Transmission function
– comparison with SLOAN confirms strategy: coincidence of the discontinuities with position of Ly and Ly
rest
rest
FFH
ST/S
DSS
Telfer et al. 2002
SLOAN
ratio: HST/SDSS
HST
Ly
Ly
main
problem: composite SED too softproblem: composite SED too soft• Korista et al. 1997 Korista et al. 1997
showed the difficulty of showed the difficulty of reproducing HeII, NV reproducing HeII, NV and CIV equivalent and CIV equivalent widths assuming a soft widths assuming a soft SED, similar to the SED, similar to the Telfer compositeTelfer composite
• photoionization models photoionization models nowadays use a much nowadays use a much harder SEDharder SED– SEDs that peak beyond SEDs that peak beyond
20eV20eV
• analysis of X-ray and analysis of X-ray and EUV spectra of 11 EUV spectra of 11 individualindividual quasars quasars revealed that the soft X-revealed that the soft X-ray excess does not ray excess does not correspond to an correspond to an extrapolation of the far-extrapolation of the far-UV powerlawUV powerlaw– Haro-Corzo et al. Haro-Corzo et al.
(submitted)(submitted)
X-ray & far-UV connection
• far-UV does not extrapolate smoothly into X-rays– Haro-Corzo et
al. (submitted)– see poster #338
11 quasars11 quasars
principal
HI : LyHI : Ly …+ …+ Lyman continuum
dust dust absorptionabsorption
inter
galac
tic
inter
galac
tic
abso
rptio
n
abso
rptio
n
intrin
sic
intrin
sic
scre
ensc
reen dis
k dis
k ph
otos
pher
e
phot
osph
ere
acce
lerate
d
acce
lerate
d
ouflo
wou
flow
AA BB CC DD
11 22 33 44
•not needednot needed•not not usefuluseful
•fit so-sofit so-so•too redtoo red
•too sharp too sharp edgeedge
•jump not jump not seenseen
•too much too much dustdust
Eastman, MacAlpine, Richstone
(1983)
1.1. intrinsic crystalline C dust, promising:intrinsic crystalline C dust, promising:– polarization polarization vsvs lambda lambda
• should model scattering using transfer code should model scattering using transfer code – René GoosmannRené Goosmann
– optical reddeningoptical reddening• SMC-like dust?SMC-like dust?• universal SED?universal SED?
– Sinhue Haro Corzo et al. (submitted) Sinhue Haro Corzo et al. (submitted) – atomic gas absorptionatomic gas absorption
• in process (Ton 34)in process (Ton 34)– infrared re-emissioninfrared re-emission
• rules out meteoritic flavorrules out meteoritic flavor• in progress: Anja Andersenin progress: Anja Andersen
– accretion disk photosphereaccretion disk photosphere• accretion disk code neededaccretion disk code needed
2.2. accelerated outflow?accelerated outflow?– speculative but tantalizingspeculative but tantalizing
conclusionsconclusions
GOAL: to
GOAL: to unmask the
unmask the accretion disk
accretion disk
(ionizing) SED
(ionizing) SED
mainCBLy ValleyACwarm
1- extragalactic HI absorption (WHIM)
F
Binette et al. 2003, ApJ 590, 58 Binette et al. 2003, ApJ 590, 58
(Å) rest-framerest-frame (Å) observer-frameobserver-framemain
predicted jump
predicted jump
NOTNOT observed
observed
A-intergalactic dust
F
==0.6
0.6rest-frame
EUV vs. z ; Telfer et al.
EUV z redshift
Binette Binette et al.et al. 2005, ApJ 631, 661 2005, ApJ 631, 661
•requires too requires too much dust much dust •excludes excludes other types other types of dustof dust
main
3- problem of accretion disk SED
• accretion disks predict break near Lyman limit– but does not quite fit
observed break of composite SED
– SED too soft to account for high ionization emission lines rest-framerest-frame
FF
Zheng 97
Hubeny Hubeny et al.et al. (2000) (2000)
main
4-accelerated outflow
(Hz)F
Eastman, MacAlpine, Richstone (1983)Eastman, MacAlpine, Richstone (1983)
He 2357He 23574342 z=2.8854342 z=2.885
Reimers et al.Reimers et al.
main
• see Eastman, MacAlpine & Richstone (1983)
• gas condensations accelerated up to 0.8 c
• model should be modified – need to blueshift
break by 0.1c– must produce a
recovery in far-UV
B- crystalline carbon dust grains
• Shang et al. (2005) explored SMC-like and ISM dust
• such dust does NOT fit UV break
• crystalline carbon grains– extinction has sharp
peak in the far-UV– can fit UV break– found in stellar disk– formation processes:
• nucleation of organic ice mixtures by UV photolysis (Kouchi et al. 2005)
• UV conversion of PAH clusters (Duley & Grishko 2001).
• …main
size 3200 Å
crystalline C
amorphous C
SMC-like
fits UV break in individual quasar spectra
• example: PG1148+459
• assumes curve D3– cubic nanodiamond
grains only– size distr. (a3.5)
• range 3200 Å
– Haro-Corzo et al. (submitted)
main log log
log
Flo
g F Haro-Corzo et Haro-Corzo et
al. 2006al. 2006
examples of quasars consistent with an E-UV recovery at 18.5 eV (670Å)
1008 0232 1307
ApJ (2005) 631, 661 ApJ (2005) 631, 661
• PG 1008+1319 zq=1.287• Pks 0232-04 zq=1.45• HS 1307+4617 zq=2.129
main
•extinction predicts a flux recovery in the extreme UV
NUV
FU
VFU
V
HST
¤
Ton 34: extremely UV deficient
• Telfer’s sample, UV break ~1100Å– 2 spectral indices
– <NUV> 0.7
– <FUV> 1.7
• Ton 34 – extreme UV break
NUV=0.3 FUV=5.3 (TZ02)
línea línea FUVFUV ==
NUVNUV
NUV
FUV
main CB disk
big blue bump
2F
F
log rest
SLOAN 2001
log
F
moyenne de 2200 spectres
Grosse Bosse Bleue (BBB)
components encountered in quasar SEDs
thermal(disk)
inverse Compton(jet)
Lichti et al. (1994)
synchrotron(jet)
F
infraredinfraredbumpbump
main
NGC5548NGC5548
HST-FOSKorista & Goad
ton34 & ngc5548
• HST-STIS(Crenshaw et al. 2003)
• warm absorber• N(H)~5 1020 cm-2
• T~ few 104 K
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