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--.. W -~-\:""-' -\W2 M 0 e.,-r ~ ~{'"1e \ f ~ 3 S- 6 eJ ~ -.~ the WcMJ 6\ e..no--t l 0+ eCtC l" r (.'iO~-,--to",,-·· -,--"~,------_l"-,,,,,-$,,--- ___ 1",crECO-seA V\..Y\ IJ e>'i'"'S e...... L J -= Q f'dZ. ZV 0 :-FJ,-- I l' we See... e ~u v \ - .-- Q. - 15 Our Visible Universe 13.9 billion ly 1 billion ly or 300 Mpc Much beyond 200 Mpc space seems remarkably uniform. This uniformity is known as "The End of Greatness" (i.e. the end of structure) C:2 ® f) (;) 0--.. (,-\-t\e b-k i \-le~;~ o..v.J ~"!;j kl:l:k __ (~~\~VV) -\\ece Tb-;s 8~ (2) ~ (3 f2 e (!) 0 ~, t;\0vJ\\:j CvA~ ~~c.<2- ~Lv\\ v'y')Clce StlAY-\- {O \""Q.JVV\, §+qlA.C'-\-)AC$ H:rc\!'Y'Ic.b~V\ ~& fe\ov"\'\lGJ;o:: ~ Vo~J ______O_T\---'. '\ex5e 1Q-\o~------~S\~f~cL~{eys-- ~ol.__~~en)C!>\J& ------=D;}.-!\'-'"-v~e::.... ('\ $~_H_.~~_-±h~ ~e-('=c \lA.$±ex:~ cYn J . ~-f£flJ"\ JY.,,;.ckL-) _ ______....:::tN_· h~i~LL__Q_f C__ -S~~>,]_~--.DJ/,\ a,...._~ z __ Hot ~ -1()QiDr ~~ _ I -----<.-~--....------....---.----.------I-,---- -.------Our Visible Universe 13.9 billion ly 1 billion ly or 300 Mpc Much beyond 200 Mpc space seems remarkably uniform. This uniformity Lets Expand is known as this arrow by "The End of Greatness" a factor of ten! (i.e. the end of structure) ~1 Gly or 300 Mpc Super clusters filaments and supervoids Giant voids Giant Clusters of Galaxies These giant clusters and voids are remnants of the initial perturbations in the background hydrogen ! Q\""~~..:? QY\J Forrv~d~6n o~ /k~JY)~ Gev\u..xi(S -~r----- ~ W\"\Q~ *be... c.LCN'"O fS =--ct. \') 'j&"-D(y~ ~ 'ON ____, ---B-_-1_ -O~ ----~\Qx ~ k>u: ~;o"cl A jl.J1;" 6 eM -\\-,e b \0-...c.1< oJ: :z ~ c, P i' <:) \J \ (h0 C 600d'------"e:..L\JLJ -c .~ ~ h e...e..d f 0 ~ es C\ -1hL b e.i±"t:c :!be 'lp--l:e.X-""-Cb C'V'\ Quasars (Quasi-Stellar Objects) or galaxies being born QSOs are bright sources from Black-Hole/Galactic-core of newly formed galaxies • Here is an artist conception • Hydrogen gas falling onto a black hole in the center of an active (nascent) galaxy. When the stuff falls in the core spits out lots of light These are observed to z 7 ' ____ ~~ -=- 0- (-t .---L)_-__- ~_="\~ _ \ " t _ 7 0- Lt} ,<2 - j 0 V') Observed time of re-ioniziation 1 0.9 real universe 0.8 0.7 0.6 0.5 a(t) 0.4 0.3 0.2 a(tre ion) 0.1 tre ion 0 -14 -12 -10 -8 -6 -4 -2 0 time (Gy) These are observed at a =1/(1 + z) 1/8, or approximately 1Gyafter big bang ' Q u""""'" fj .yV11 ercI (\lk c- c~ J,"\ ~L-'(~~{ (\ 'o~G f ¢.\CY'f\ ~ fee i-cO- \;>\..., \. \e 1"",('\ " The smallest discrete wavelength that is emitted is in the UV and is known as the Lymann-↵ line. Watch the video Ly ↵ = 121 nm ------+------~------ ~13. G eV / / / / E \ // / \) I------'-~ / . \ r. , - '-\ - ~ re> \.A\' it 0 t ______AV\ JeC4rIOO C10JJ L Zero· -k-~ c;; \ -:..-(6, G, ~V/l"t.::. 'd- ,0 l.AJ'\d St cd:~ _ ~ 0'1\ b (J2x, tc~_\ () u-IlorcA:ki.cV'\ J tre~ ~G\ t:6 2'-- se.co \"\.d A\s reck e.. 9ll"'lCe. be Cvt Sor 112,-, } //1/, ,~ v E ~ - - \S.~LV -- \ 3~b . b~ t" ------.:= '1L.. \L Or \o~~J-J ~ Jn~\ &e.~'V' ('(I', J) ~ -.\k A \SO ~y- a':'/\ ~ @ A{ ~ f'e.J. - 5\~~t-r Sj'j l0\oJ wotA.IJ b 0* 0 t:'"~~:rS±~cA: jk Lb-rx (ivI) ~ ('1"\ A -= =- .0 > Q \2\ '('I~ ~ ~\ \T/ 1 E c .,.- ... -I . I ....0 II C/) ._._-. C/) .Y I - -I I 0 E ctJ 0 tt Q) I() 0 Q) - - -I- 0) ~ !...... 0...... , Il (\S I C/) -+-' Q. 0 ------.. 0 0> (\S ~ ------r 0 0) c ..c (\S ------if ..c « $ C/) - 0 . \- ~ - .. - - "" I (J) o~ ~ f'- - 8'-'" :if ---t- \1\ CO.c E :s: ~:.J (~ -+J ~ -r Ol 0 j. c '- v \I' -+-' Q) ...... , j r-.. ,- r-.. .,...--, v') \ r-.. N 0> 00 ~ 8v C/) \..... I() > 00 ~ ~ "J 0> r--- 0 -!-' .s C'! ~s ~ l{) <- ari ~ «) -+- ~ 0> ... II ~ cJ Iii 3, II~ II L. C N "VJ N --r- N 6 ..~I '-'"0 ~----- '-'" L- '-'" C+- o to to r5 0 « V c.y 0 '-...... t 0 to --- (l-V Z_WO L_S f)Ja Ll-O~) ' ------'------==----....~_~_____=_)"J--:: -/\', C ~ -= ~ c. ( 2}-IO, <. If n t!:l ___ (Z I n Y'1 A E"" J(). 2eV C!1 Q ~ ? ...--. ...- -.:: ~ ~"- ....1C'"':----''2;;'l- / := Inn 3 2 1 transition Quasar 1: (closest) Emission of 3 1 transition Hydrogen Lines from the Quasar obs =(1+z) 121 nm = 8490A˚ Quasar 2: (farther) The peaks move because the red-shift is changing for the three quasars Quasar 3: (farthest) meaured Intensity per frequency Intensity per Fig. 1.— Optical spectraWavelength of z 5.8quasarsobservedwithKeck/ESI,intheobservedframe.The in Angstroms, 10 Angstromsspectra have = been 1 smoothednm to 4A˚ 1 pixel ,andhavebeennormalizedtotheobservedz band flux. The spectrum of SDSS1044–0125 has been taken from Fan et al. (2000). In each spectrum, the expected wavelengths of prominent emission lines, as well as the Lyman limit, are indicated by the dashed lines. --- , QM ~? ,~ ~50rbeJL4J __ @ ~f -\h" So ,-,-re.£' is"",",,, 0 t "& -\0 {he.. ""idk~ of {t~ S, ee..J V Je.&cr-ll.,e. ~ ,. oj', I:0.J;"J~ Llbt, ..... dQ}\e.c..-t,r ) L.X>\J J ,se.e. ? "':1s 4:~ wc.v..J~\eV"\81l. to h~eN or S hortev- qt-S {h ea$IA ce L 0'\ ~ -+k cle~eei Cv.l\d !\,,~ ~GLS - o 8 0 • \ b~(\ Sor ~j wC"A';~OODi)" {lJ is <1vv\:\\~"r ~~ -\:v--e (}\dA.5PVc (d-\-t~ A < e ------ / <-- -- '\ I I 7i 0 7' "< o " tk ' \:\~~-t k.,b ~I-e p~\c...... >+~~~ -----1\A0--~u-x-,s -''S n.hsor ~~.\. bj i\", -f'Lee. ~0J.<""o 't~, (jO--b 0....\: ,rA\·..,..~"\ fd- Sh.~rh \t --/' ..\-0 oJ~s o~ *k ------+-\ ----=-\-Ldl.,,1: 1=0:<",~_ V\e.0 qJo-xi &-5 3 Quasar 1: (closest) Quasar 2: (farther) Quasar 3: (farthest) What is Different about this? Intensity per frequency Intensity per Fig. 1.— Optical spectraWavelength of z 5.8quasarsobservedwithKeck/ESI,intheobservedframe.The in Angstroms, 10 Angstromsspectra have = been 1 smoothednm to 4A˚ 1 pixel ,andhavebeennormalizedtotheobservedz band flux. The spectrum of SDSS1044–0125 has been taken from Fan et al. (2000). In each spectrum, the expected wavelengths of prominent emission lines, as well as the Lyman limit, are indicated by the dashed lines. 3 The quasar is emitting light at Quasar 1: (closest) wavelengths shorter than the Ly-alpha wavelength Quasar 2: (farther) But for the largest z this Quasar 3: (farthest) light is absorbed. There is nothing here. Intensity per frequency Intensity per Fig. 1.— Optical spectraWavelength of z 5.8quasarsobservedwithKeck/ESI,intheobservedframe.The in Angstroms, 10 Angstromsspectra have = been 1 smoothednm to 4A˚ 1 pixel ,andhavebeennormalizedtotheobservedz band flux. The spectrum of SDSS1044–0125 has been taken from Fan et al. (2000). In each spectrum, the expected wavelengths of prominent emission lines, as well as the Lyman limit, are indicated by the dashed lines. What the last slide shows: 1. When: between z 6 and z 6.5 (about 1Gy) after the big bang. ' ' 2. What: the amount of neutral hydrogen in the universe dramatically changed 3. Conclude: - The neutral hydrogen clustered into galaxies and formed ionized plasma again.