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Rachel Dudik , U. S. Naval Observatory, Washington DC Kim Weaver & Tim Kallman , NASA GSFC, Greenbelt MD. Surse de raze X ultraluminoase : Estimari de luminoziate cu Spitzer. Ciprian T. Berghea U. S. Naval Observatory, Washington DC Computational Physics, Inc., Springfield VA.
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Rachel Dudik, U. S. Naval Observatory, Washington DC Kim Weaver & Tim Kallman, NASA GSFC, Greenbelt MD Diaspora Stiintifica - 23 Sept 2010 Surse de raze X ultraluminoase:Estimari de luminoziate cu Spitzer Ciprian T. Berghea U. S. Naval Observatory, Washington DC Computational Physics, Inc., Springfield VA
Diaspora Stiintifica - 23 Sept 2010 Ce sint acesteULXs ? (Ultraluminous X-ray Sources) Surse de raze X in galaxiiinvecinate (nu in nucleu), care radiazaprinacretie cu luminozitaticedepasesclimitaEddingtonpentru o gauraneagra (BH) cu masa de 20 M๏ LX > 1039 erg s-1 Celemailuminoase ULXs au LX > 1041 erg s-1 Din anii 80, maimult de 200 ULXs au fostdescoperite in galaxiile din apropiere cu telescoapele de raze X (Einstein, ROSAT, ASCA, XMM-Newton, Chandra, Suzaku). Inca nu exista o explicatiegeneralasatisfacatoarepentruacesteobiecteenigmatice. Rosu: 0.3-1.5 keV Verde:1.5-2.5 keV Albastru: 2.5-8.0 keV
Diaspora Stiintifica - 23 Sept 2010 De cesintasainteresante ? • Luminozitateaextrema a permissugestiaexistenteigaurilornegre cu masemijlocii(Intermediate-Mass Black Holes, IMBH). Acestearaveamasemaimaridecit BH stelaredarmaimicidecitnuclee active (AGN). • Probleme cu acestscenariu: cum se formeaza? Din stele de Populatie III? In roiuristelare dense? Scenarii alternative maiputinexotice 1. Microquasar Radiatia e colimatasi ULXs aparluminoasefiindcasintprivite de-a lungulaxeidiscului de acretie. 2. Acretie super-Eddington Anumitemodele de acretiesugereaza ca limitaEddingtonpoatefidepasita in anumiteconditiicind rata de acretie e foarte mare.
Diaspora Stiintifica - 23 Sept 2010 NebuloaseIonizatesi SS433 Pakull, M. W., & Mirioni, L. 2003, Revista Mexicana de Astronomia y Astrofisica Conference Series, 15, 197 H H Holmberg IX X-1 NGC1313 X-2 Microquasarul SS433 SS433, W50 Singurulobiect in CaleaLactee care “seamana cu” un ULX. Numitasa in catalogul din 1977 compilat de Nicholas Sanduleaksi Bruce Stephenson. Radio over H Boumis, P., et al. 2007, MNRAS, 381, 308
Diaspora Stiintifica - 23 Sept 2010 Observatii ULX cu Spitzer Observatii cu rezultatebune (din archiva, prezentateaici) Holmberg II ULX MF 16 ULX Observatiipropuse, fararezultate M81 X-6 Infrared Spectrograph (IRS) 1. Rezolutie scazuta 5.2 - 38.0 µm 2. Rezolutie inalta 9.9 - 37.2 µm - Modulul Short-High 9.9 - 19.6 µm dimensiuni: 4.7 - 11.3 - Modulul Long-High 18.7 - 37.2 µm dimensiuni: 11.1 - 22.3 Propuse, cu ghinion IC 342 X-1 NGC 2403 X-1 Holmberg IX X-1 NGC 5204 X-1
Diaspora Stiintifica - 23 Sept 2010 Holmberg II ULX in “NebuloasaPicior” Observatii cu Spitzer IRS in “mapping mode”: aperturile LH and SH Holmberg II ULX situat in “Calciiul” nebuloasei H “Foot Nebula” HST ACS image: 814W (R), 658N (G, H), 550M (B) Spitzer IRS CUBISM spectral maps, from the SINGS Legacy Program
Diaspora Stiintifica - 23 Sept 2010 MF 16 SNR si ULX-uleivazute de Spitzer ULX-ul in interiorul ramasitei de supernova MF16 din NGC 6946 Observatii cu Spitzer IRS in “mapping mode”: aperturile SH and LH F140PL (UV) 658N (Hα)
Diaspora Stiintifica - 23 Sept 2010 Spectre Spitzer IRS (10 - 35 m) • [O IV] 25.89 µm e o linie de inalta ionizare, implica o surse de inalta energie. • E dedectata de regula in Nuclee Active (AGN - Active Galactic Nuclei ). • Modelarea cu Cloudy arata ca in ambele cazuri linille de inalta ionizare observate sint consistente cu un proces de fotoionizare de catre ULX si nu cu colimatie puternica • Luminozitatea e intr-adevar asa inalta cum se masoara in observatiile cu rad. X Holmberg II ULX MF16 ULX
Diaspora Stiintifica - 23 Sept 2010 Diagnostice cu linii in IR
Diaspora Stiintifica - 23 Sept 2010 Modele de Soc siFotoionizare, Predictii cu Mappings III Viteza de soc in km/s, parametrul magnetic in G cm3/2
Diaspora Stiintifica - 23 Sept 2010 Spectral Energy Distribution – The Base Model The input spectrum of the ionizing source for photoionization modeling Photometry:Spitzer IRAC, XMM-Newton’s Optical Monitor, GALEX Previously published: • An optical counterpart: a B3Ib – O4V star (Kaaret et al. 2004) • Radio VLA data (Miller et al. 2005) X-ray models: PLMCD (PL + MCD) BPL (Broken PL) Modified PLMCD -> Base Model
Diaspora Stiintifica - 23 Sept 2010 Photoionization Modeling – CLOUDY predictions CLOUDY modeling: spherical geometry, gas density = 10 cm-3, metallicity = 0.1 Z๏, inner cloud radius = 0.1 pc, filling factor = 1 Input Ionizing Spectra Radiation bounded 1. Base Model (Modified PLMCD), bolometric luminosity: 1.3 x 1040 erg s-1 2. PLMCD-based model (PL + MCD) 3. O5 star (replacing the B2Ib star) Matter bounded 4. BPL-based model (broken power-law)