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NEW LOCAL IGM RESULTS FROM THE COSMIC ORIGINS SPECTROGRAPH

NEW LOCAL IGM RESULTS FROM THE COSMIC ORIGINS SPECTROGRAPH JOHN STOCKE, U of COLORADO for the COS GTO Team. Collaborators: Mike Shull, Jim Green, Charles Danforth & Brian Keeney at Colorado; Blair Savage and Anand Narayanan at Wisconsin. OUTLINE OF THE TALK.

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NEW LOCAL IGM RESULTS FROM THE COSMIC ORIGINS SPECTROGRAPH

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  1. NEW LOCAL IGM RESULTS FROM THE COSMIC ORIGINS SPECTROGRAPH JOHN STOCKE, U of COLORADO for the COS GTO Team Collaborators: Mike Shull, Jim Green, Charles Danforth & Brian Keeney at Colorado; Blair Savage and Anand Narayanan at Wisconsin

  2. OUTLINE OF THE TALK • Baryon Census: A new type of broad, shallow IGM/WHIM absorber (O VI-only) first discovered in COS spectrum of PKS 0405-123 Closing in on a complete census of baryons with HST • QSO absorbers near galaxies: Contents of Galaxy Halos and Kinematics. Out-flowing Winds or In-falling Fuel ? • What’sUp-coming for COS GTO ?

  3. THE LOCAL BARYON CENSUS THECHARGE IN 2004 FROM MY OLD FRIEND AND OBSERVING BUDDY: “COMPLETE THE BARYON CENSUS with HST” …AND AN EXAMPLE OF THE DOWN HOME-STYLE WISDOM FOR WHICH HE WAS FAMOUS: “Images are great! But, come on folks, if you want to do astrophysics, you need to do spectroscopy” Prof. John Huchra in his summary talk at the StScI Conference “Planets to Cosmology: Essential Science in the Final Years of the Hubble Space Telescope” (2004)

  4. COS vs. STIS The Intergalactic Medium • PKS0405-123 • z=0.573, F 2 x 10-14 ergs cm-2 sec-1 Å-1 • 9.7 ksec (G130M) vs. 27 ksec (STIS) gives large S/N ratio improvement • Survey capabilities • Spatial mapping • Metals, diffuse IGM Savage et al. 2010 ApJ 719, 1526. HIGH SIGNAL-TO-NOISE DETECTS SHALLOW, HIGH TEMPERATURE ABSORBERS WITH CONFIDENCE !

  5. COS vs. STIS : Detecting Weak Lines XX 9.7

  6. Strong OVI Absorbers Five strong O VI absorbers are seen in the PKS 0405-123 data. The Lyα system at z=0.167 shows several velocity components, including broad absorption at -270 km/s in O VI with no equivalent H I. This could represent gas at T≈106-6.5 K associated with gas in a spiral-rich galaxy group. * * • Savage et al. 2010 ApJ 719, 1526. * = nearest galaxy velocities

  7. ? Galaxy environment @ z=0.167 is still uncertain  OVI absorber is group gas? ? ? ? ?? ? ?

  8. HE 0153-4520: z=0.226 HI + OVI SYSTEM: BROAD Lyα + OVI on top of a narrower H I absorber… tough to de-convolve ! NARROW, PHOTOIONIZED ABSORBER: log NHI = 16.6 and with b=26 km/s BROAD ABSORBER: log NHI = 13.6 and with b=145: km/s O VI: log N=14.2 and b=37 km/s ALSO HAS: C II, C III, N II, N III, Sii II, Si III  Log U = -2.6  Cannot account for O VI ! b-values  log T = 6.1 oK : O VI velocity offset: 10—15 km/s ** SEE SAVAGE POSTER

  9. IMPLICATIONS if OVI-only systems are SPIRAL-RICH GALAXY GROUP GAS WHAT WE SEEWHAT MULCHAEY et al (1996) predicted log T = 6.1 K log T = 6.3 K (based on bHI≈ 100 km/s) (based on σ ≈ 100 km/s) log NH = 19.9 cm-2 log NH≈ 20 cm-2 assumed size ≈ 200--400 kpc inferred gas mass ≈ 1010-11 Mסּ For # density of spiral-rich galaxy groups ≈ 10-3 Mpc-3 • b ≈ 2—20% of total Comparable to stellar mass in Spirals

  10. Local Baryon Census (PRE-COS: c. 2009) “missing” ~40% WHIM (BLAs) 14% WHIM (OVI+BLAs) ~20% 7% galaxies 8% Lyα Forest 30% clusters ~3% cold HI <1% WHIM (OVI) Danforth, Stocke & Shull, 2010, ApJ, 710, 613 arXiv:0912.1603

  11. Local Baryon Census (COS + 1 year: c. 2010) Spiral Group Gas 2-20%? Todd Tripp talk on Friday “missing” 20-40% WHIM (BLAs) 14% WHIM (OVI+BLAs) ~20% 7% galaxies 8% Lyα Forest 30% clusters ~3% cold HI <1% WHIM (OVI)

  12. HST/COS FUV Spectrum of BL Lac Object: 1ES 1553+113: a BL Lac at z > 0.4 (Danforth et al. 2010 ApJ) a triple OVI system Ly α absorber | From Danforth et al. 2010 ApJ submitted & 2010 arXiv 1005.2191 UNAMBIGUOUS OVI REGION OVI COVERAGE FOR z = 0.4 SEE CHARLES DANFORTH POSTER ON COS BL LACS UPSTAIRS FOR SOME SURPRISES!

  13. 1ES 1553+113 triple Lyα/O VI system at z≈0.188 detected in O VI, N V & C III Different than OVI-only systems: Structure suggests shock interfaces between absorbers, not thermally relaxed Shocked gas in a Galaxy Filament ? 500 ksec Chandra spectroscopy in-progress Lyα OVI 1032 OVI 1038 CIII 977

  14. QSO absorbers near galaxies:Out-flowing Winds or In-falling Fuel ? • MANY INVESTIGATORS ASSUME THE ANSWER • STARBURST GALAXY WINDS are assumed to be rather ubiquitous and to usually escape into IGM promoters: “BALLISTIC IMPERIALISTS” 2. COLD MODE ACCRETION IN FORM OF HIGH VELOCITY CLOUDS are assumed to be present around all massive halos. Low metallicity gas must be accreted by big galaxies to fuel on-going star formation episodes. promoters: “FEEDING FRENZY ENTHUSIASTS” • BUT which of these are being seen as QSO absorbers ? • ONLY POSSIBLE TO ANSWER for specific cases AT VERY LOW-z (≤ 0.1) Using QSO/galaxy pairs with COS • GTOs + GOs Heckman, Tumlinson, Turnshek, etc.

  15. QSO ABSORPTION LINE STUDIESOF QSO/GALAXY PAIRS:But gas motion is hard to interpret unambiguously H II regions in red in ESO G1327-2041 PKS 1327-204 HI 21cm Ejected Nucleus? TIDAL HVC DISK GAS (INFALL or (velocity of H II OUTFLOW ?) regions in disk) Can’t Tell for Sure ! Keeney et al. AJ 2010 submitted

  16. SBS 1122+594 zem = 0.852 czabs = 1178 ± 15 km s−1 6.6 arcmin (34 kpc) IC 691 L ≈ 0.05 L* czgal = 1204 ± 3 km s−1 COS ABSORPTION LINE STUDIESOF QSO/GALAXY PAIRS: An Isolated Dwarf Starburst Galaxy

  17. Full COS Spectrum of SBS 1122+594 z=0.852 ZQSO = 0.852 S/N = 18 AIR GLOW LINES x x LLS at z~0.56 From Keeney et al. in preparation.

  18. DETECTING AN OUTFLOWING (?) WIND FROM A DWARF STARBURST GALAXY: Absorber Characteristics: log N_HI ~ 16.5: cm-2 b~ 30—50: km/s [Z] ~ -1.2 [Zgal] ~ -0.7 from HII regions High Ionization gas w/ slight overabundance of Si/C Abundances indicative of outflow; kinematics inconclusive SBS 1122+594 zem = 0.852 czabs = 1178 ± 15 km s−1 6.6 arcmin (34 kpc) IC 691 L ≈ 0.05 L* czgal = 1204 ± 3 km s−1 Si II not detected

  19. Uncertain inclination angle and galaxy mass estimators plus low Δv leaves uncertain whether gas escapes into IGM. ESCAPE VELOCITY ABSORBER RELATIVE VELOCITY GALAXY INCLINATION ANGLE  IF OUTFLOW IS PERPENDICULAR TO GALAXY DISK, GAS IS MARGINALLY-BOUND

  20. “TRIPLE-PROBE” OF A ½ L* GALAXY HALO Only high ions detected at low Δv and NO METALS detected at 100 kpc out minor axis !!! X X BLUE SPECTRUM X X RED SPECTRUM 0.42 xxx BLACK SPECTRUM

  21. HERE’s ONE WHERE WE CAN BE MORE CERTAIN WF/PC2 Hα Image shows no plumes or wisps in direction of 3C232  not outflow? Greater obscuration of H II regions to bottom of NGC 3067 support H I rotation-curve analysis favoring “underside” view of NGC 3067  gas seen in H I absorption is infalling Stocke, Keeney & Danforth 2010 PASA, 127, 256 (2010) & arXiv 1002.5003). 3C 232 NGC 3067

  22. Is Absorbing Gas Infalling or Outflowing? • If we can pin down the 3D orientation of the galaxy we can use the velocity information to determine whether absorbing gas in infalling or outflowing, assuming that absorbing gas is moving perpendicular to the galaxy disk (better assumption for outflow than infall). • Ways to Determine Orientation: • High-res Imaging to look at distribution of H II regions (numbers and integrated luminosities). • High-res Spectroscopy to look at Balmer decrement as a function of position in the galaxy. Blueshift Redshift

  23. MgII/Lyman Limit Systems as HVC Analogs NGC 3067 H I Absorber NHI = 1.0 x 1020 cm-2 Tspin= 500 ± 200 K Tkin = 380 ± 30 K R(Galactocentric)= 11 kpc Cloud Size = 5 kpc Z ≈ 0.25 Z8 UV fesc < 2% Galactic HVCs NHI > 2 x 1018 cm-2 Tspin > 200 K R(Galactocentric) < 40 kpc Cloud Size = 3-20 kpc Z = 0.08-0.35 Z8 UV fesc= 1-2% Keeney et al (2005) Putman et al (2003) Tumlinson et al (1999) Akeson & Blitz (1999) Stocke, Keeney & Danfoth (2010) Collins, Shull, & Giroux (2004) Hulsbosch & Wakker (1988)

  24. Upcoming COS GTO Observations : Six Probes of a Section of the “Great Wall” (Penton Poster here) SOLID LINES ARE COS TARGET SIGHTLINES UPCOMING OBSERVATIONS: 5 SNR ~30 TARGETS; 4 DWARF GALAXY PROBES; 3 STARBURST GALAXY PROBES ; 2 NEW FEATURELESS BL Lac OBJECTS …AND A PARTRIDGE IN A PEAR TREE!

  25. CONCLUSIONS • COSis delivering SNR > 15 at R≈ 18,000 for GTOs, four large GO programs (S.Morris, T. Tripp & J. Tumlinson, PIs) and several smaller programs. • OVI-ONLY ABSORBERS may be gravitationally-heated GAS IN SPIRAL-RICH GALAXY GROUPS AT T ~ 106 K. If so, this gas can account for up to 20% OF BARYONS in low-z Universe. *** Important to find more of these and conduct deep galaxy surveys in their vicinities *** • INFALL OR OUTFLOW CAN BE DISTINGUISHED IN SOME CASES for QSO Absorber/Galaxy Pairs where the nearby disk galaxy is at an intermediate inclination angle. *** Important to observe many nearby examples to establish infall/outflow frequencies of QSO absorbers ***

  26. VOID VOID VOID FILAMENT GASEOUS FILAMENT

  27. TEN MORE YEARS?

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