deciphering the ancient universe with gamma-ray bursts
DESCRIPTION
Deciphering the Ancient Universe with Gamma-Ray Bursts. http://www-tap.scphys.kyoto-u.ac.jp/GRB2010/. Nobuyuki Kawai (Tokyo Tech). Cosmic Time. GRB as a probe for high- z Universe. GRB as a luminous light source GRB as a mark for a death of a massive star. Neutral opaque Universe. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/1.jpg)
Deciphering the Ancient Universe with Gamma-Ray
BurstsNobuyuki Kawai (Tokyo Tech)
http://www-tap.scphys.kyoto-u.ac.jp/GRB2010/
![Page 2: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/2.jpg)
Cosmic Time
Neutral opaque Universe Ionized
transparent Universe
GRB as a probe for high-z UniverseGRB as a luminous light source
GRB as a mark for a death of a massive star
![Page 3: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/3.jpg)
3
Imprints in GRB spectra
Molecular Cloud
H II Region
WR Wind Shell
SN ejecta
galaxy ISM
IGM
Ejecta CSM SFR ISM IGM
![Page 4: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/4.jpg)
4
Lya break
SII
SiII*OI CII
SiII
GRB 050904 at t=3.4 d
Subaru FOCAS 4.0 hrs, l/Dl»1000Kawai et al. (2006)Totani et al. (2006)
[S/H]=-1.3
Log NHI=21.6
zIGM,u = zDLA = 6.295 best fit xHI = 0.00 xHI < 0.17 (68 %
C.L.) 0.60 (95%
C.L.)
![Page 5: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/5.jpg)
History of the Universe
5
• Reinization• Chemical
evolution• Star formation
rate
IGM
Neu
tral F
ract
ion
Met
allic
ity
Cos
mic
star
form
atio
n ra
te
![Page 6: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/6.jpg)
“Tanvir Plot”
Tanvir 2009
GRBs
Galaxies
Quasars
![Page 7: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/7.jpg)
7
960 970 980 wavelength [nm]
2 1 0 Flux density
Lya
700 800 900 1000 wavelength [nm]
1
0
Lya
S+
Si+Si+
O C+
800 900 1000 wavelength [nm]
30
20
10
0
Lya
optical/NIR spectra of highest-z objectsGalaxyz = 6.96
Quasarz = 6.4
GRBz = 6.3
•Lyman alpha emitter•can be found with
systematic wide-field narrow band survey + spectroscopy•little information in
spectra (e.g. metal?)•luminosity selected
•very rare: only 10 at z>6 in SDSS•steadily bright•complicated
spectra: difficult to interpret•proximity effect•luminosity-
selected
•rare: ~<5% at z>6 ?•bright at early phase•simple intrinsic
spectra: abundant information
•no proximity effect•sampling normal
star-forming glaxy
![Page 8: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/8.jpg)
8
Agenda What do we know about GRBs? What do we know about the
ancient Universe? How can we use GRBs to
understand the history of the Universe?
What are the future prospects?
![Page 9: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/9.jpg)
9
Poster Competition Eligible if you are not giving a
talk Indicate your entry by the color
sticker Entry closed at Monday afternoon
Anonymous Judges choose three winners
Winners give 10 min talk on Friday
Young participants (students, postdocs) are particularly encouraged
![Page 10: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/10.jpg)
10
Cosmic Chemical Evolution
Fynbo et al. 2006Prochaska et al. 2003Sollerman et al. 2005Savaglio, et al. 2009
GRB 050904Kawai et al. 2006
![Page 11: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/11.jpg)
11
Reionization
![Page 12: Deciphering the Ancient Universe with Gamma-Ray Bursts](https://reader035.vdocuments.net/reader035/viewer/2022062501/56816334550346895dd3bc2e/html5/thumbnails/12.jpg)
12
Star Formation Rate