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ガンマ線バーストと遠方宇宙・元素の起源� 井上 進�（理研） ＋共同研究者の皆様 Grbs, Blazars

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ガンマ線バーストと遠方宇宙・元素の起源� 井上 進�（理研） ＋共同研究者の皆様 Grbs, Blazars ProbingwithTMT the (more 時代のFirst than) Stars,GRBsGRB a forUVlittleで切り拓く超遠方宇宙� UNravelling Radiation, help from the B my DarkFields, friends Ages Dust… Mission� GeV Fermi ガンマ線バーストと遠方宇宙・元素の起源� 井上 進�（理研） ＋共同研究者の皆様 GRBs, blazars R. Salvaterra, T. R. Choudhury, A. Ferrara, B. Ciardi, R. Schneider 分子 ALMA (MNRAS in press, arXiv:0906.2495) Y. Inoue, M. Kobayashi, T. Totani, Y. Niinou (in prep.) z~30-6 ダスト ASTRO-H blazar HiZ-G GRB SPICA 再電離 金属 TMT submm R.ALMA Salvaterra,5@5 T.epoch R. Choudhury, of first starA. Ferrara, formation Inoue, （磁場）� Omukai & Ciardi, Benedetta MNRAS, Ciardi Firstsubmitted (MPA)Radiation (astro-ph/0502218) Fields,! FirstB. MagneticCiardi, R. Schneider Fields,lots of First theory Star Formation SKA K. Ichiki, K. KiyotomoTakahashi Ichiki (CfCP/NAOJ) but almost no observations!!! K. Omukai Keitaro Takahashi (Princeton) IceCube SKA CTA CTA “in an interstella burst i am back to reveal the universe” radio see - after T. Yorke also かなた outline� I. GRBs and the high-z Universe - overview: early excitement vs recent calming down - quasar contribution to reionization - gamma-ray probe of UV background *star formation rate, metal evolution, damping wings… -> later talks recent reviews: Space Sci. Rev. (2016) 202� II. neutron star mergers and r-process nucleosynthesis - potential of X-ray diagnostics cosmic dark ages -> cosmic dawn� - big bang� z~3600� - matter-rad. eq.� z~1000� - recombination� dark ages� z>~30� - first stars, galaxies, black holes… -> reionization z~8-10� z~6� - reion. ends - star formation � z~1-3 peak� z~0� adapted from Djorgovski� GRBs and high-z Universe� 2000’s: excitement, hope GRBs� high-z� 1967 discovery (670702) … 1997 afterglow, cosmological z (970508) 2000 potential recognition ~2000 first star simulations Lamb & Reichart 00 2001 quasar GP troughs Bromm & Loeb 01…� 2003 massive star (030329) 2003 CMB optical depth zreion~17?? 2005 z=6.3 (050904) 2009 z=8.2 (090423) high-z GRB mania!� record redshifts (spectroscopic): -2009 (GRB 090429 z~9.4)� GRB 090423 z=8.2� ©山崎� record redshifts (spectroscopic): -2017 (GRB 090429 z~9.4)� GRB 090423 z=8.2� ©山崎� 2015� 2020� record redshifts (spectroscopic): -2017 quasars strike back?� (GRB 090429 z~9.4)� GRB 090423 z=8.2� ULAS J1120+0641 z=7.085� ©山崎� 2015� 2020� record redshifts (spectroscopic): -2017 galaxies strike back!� GN-z11 z=11.09 EGSY8p7 z=8.68� (GRB 090429 z~9.4)� GRB 090423 z=8.2� ULAS J1120+0641 z=7.085� ©山崎� 2015� 2020� The Astrophysical Journal, 819:129current(11pp), 2016 March 10highest-z object: galaxy atOesch z=11.09 et al. Oesch+ 16� The Astrophysical Journal, 819:129 (11pp), 2016 March 10 Oesch et al. Table 3 Assumed LFs for z ∼ 10–11 Number Density Estimates -5 Reference f * 10 M* α Nexp (Mpc−3)(mag)(<−22.1) Figure 5. Grism Spectrum of GN-z11. The top panel shows the (negative) 2D spectrum from the stack of our cycle 22 data (12 orbits) with the trace outlined by the Bouwensdark et red al. lines.(2015b For clarity) the 2D spectrum1.65 was smoothed by− a20.97 Gaussian indicated− by2.38 the ellipse in the 0.06 lower right corner. The bottom panel is the un-smoothed 1D flux density using an optimal extraction rebinned to one resolution element of the G141 grism (93Å). The black dots show the same further binned to 560Å, while the Finkelsteinblue line et shows al. ( the2015 contamination) level0.96 that was subtracted− from20.55 the original object−2.90 spectrum. We identify 0.002 a continuum break in the spectrum at λ=1.47±0.01 μm. The continuum flux at λ>1.47 μm is detected at ∼1–1.5σ per resolution element and at 3.8σ per 560Å bin. After excluding lower redshift solutions (see the text and Mashian et al. (2015fi ) 0.25 +0.08 −21.20 fl −2.20 0.03 fl Figure 4), the best- t grism redshift is zgrism = 11.09-0.12. The red line re ects the Lyα break at this redshift, normalized to the measured H-band ux of GN-z11. The Mason etagreement al. (2015 is excellent.) The fact that we0.30 only detect significant−21.05flux along the trace−2.61 of our target source, 0.01 which is also consistent with the measured H-band magnitude, is strong evidence that we have indeed detected the continuum of GN-z11 rather than any residual contamination. Trac et al. (2015) 5.00 −20.18 −2.22 0.002 this flux detection is ∼1–1.5σ per resolution element longward 3.1. The Best-fit Solution: A z∼11 Galaxy of 1.47 μm and consistent with zero flux shortward of that. The Note. The parameters f*, M*, and α represent the three parametersBased onour of previous the photometric redshift measurement for total spectral flux averaged over 1.47–1.65 μm represents a GN-z11 (z = 10.2), we expected to detect a continuum Schechterclear UV 5.5σ LFdetection. taken This from is fullythe different consistent with papers. the prediction phot break at 1.36±0.05 μm. This can clearly be ruled out. from the exposure time calculator for an H=26 mag source in However, the grism data are consistent with an even higher a 12-orbit exposure. The extracted 1D spectrum along the trace of GN-z11 is shown redshift solution. Interpreting the observed break as the 1216Å in Figures 4 and 5.Thesehighlightthedetectionofacontinuum break, which is expected for high-redshift galaxies based on absorption from the neutral inter-galactic hydrogen along the when assumingbreak with a flux a ratio more of ff()()ll realistic<><1.47 case 1.47 where 0.32 at the emission line line of sight, we obtain a very good fit to the spectrum with a fl 2σ when averaged over 560 Å wide spectral bins. 2 Figure 7. Redshift and UV luminosities of known high-redshift galaxies from ux isfl distributed over a combination ofreduced linesχ =(e.g.,1.2 (see Figures 4 and 5). The best-fit redshift is A ux decrement is seen around ∼1.6 μm, which is caused +0.08 blank field surveys. Dark filled squares correspond to spectroscopically fi zgrism = 11.09 , corresponding to a cosmic time of only Hβ+by[O negativeIII]),fl weux values can in conone of ourdently two visits invalidate slightly above such a solution.-0.12 confirmed sources, while small gray dots are photometric redshifts (Bouwens the peak of the trace of GN-z11. However, this dip is consistent ∼400 Myr after the Big Bang. The grism redshift and its fi The lowerwith Gaussian left panel deviates in from Figure the noise4 model.compares We also tested the measureduncertainty grism are derived from anet MCMC al. 2015bt to). the GN-z11 2D spectrum clearly stands out as one of the most luminous currently spectrumthat the with detected that continuum expectedflux is still for present the when best- adoptingfit lowerwhich also redshift includes the morphologicalknown galaxies information at all of redshifts the z>6 and is by far the most distantmeasured different stacking and extraction procedures (see Appendix A). source as well as the photometry,galaxy adopting with identical spectroscopy techniques(black squares; see Oesch et al. 2015b, for a full list solution we had previouslyfi identified (Oesch etas al. used2014 for) the.A 3D-HST survey redshifts (see Momcheva In particular, we con rmed the spectral break in a simple of references). Wider area surveys with future near-infrared telescopes (such as strongmedian line stack emitter of the individual SED is continuum-subtracted clearly inconsistent 2D grism withet al. 2015 the). data. observations of our six individual visits. Additionally, we This high-redshift solutionWFIRST also reproduces) will be the required expected to determine how common such luminous sources Apartcon fromfirmed the that the emission continuum break lines, is seen which only along we the trace do notcount detect, rate based this on an H=26really mag continuum are at z source,>10. as well modelof also our spectrum predicts by creating weak simple continuum 1D-extractions aboveflux and acrossas the the overall whole morphology of the 2D grism spectrum. This is below the trace of our target source. Finally, we confirmed that demonstrated in Figure 3, where we show the original data, the wavelength range. At <1.47 μm, this is higherneighbor than subtracted the 2D spectrum as well as the residual after short long a break is seen in both epochs separately (see Figure 10). the observed spectrum has a break of (1->ff) 0.68 observedIn mean, the following while sections, at > we1.47 discussμm the thepossible expected redshift flsubtractingux is too out low the z=11.09 model with the correct H-band nn solutions for GN-z11 based on the combined constraints of the magnitude. Note the drop of theatfl 2uxσ longward, thus of indicating 1.65 μm due again that we can marginally rule out a comparednew grism to the continuum observations. detection as wellOverall as the the pre-existing likelihoodto the of reduced a z∼ sensitivity2 of4000 the grism.Å Thisbreak is an important based on the spectrum alone without even extremephotometry. emission line SED based on our grism dataconstraint, is less because than it shows that the detected flux originates −6 including the photometric constraints. 10 and can be ruled out. 5 Note that in very similar grism observations for a source triply imaged by a CLASH foreground cluster, emission line 4. DISCUSSION contamination could also be excluded (Pirzkal et al. 2015). We 4.1. Physical Properties of GN-z11 thus have no indication currently that any of the recent z∼9–11 galaxy candidates identified with HST is a lower Despite being the most distant known galaxy, GN-z11 is redshift strong emission line contaminant (but see, e.g., relatively bright and reliably detected in both IRAC 3.6 and Brammer et al.
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