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Suman Majumdar
Institute for Astronomy Stockholm University source:- arXiv:1209.4762
- Somnath Bharadwaj
(IIT Kharagpur, India)
- Tirthankar Roy Choudhury
(NCRA-TIFR, India)
Epoch of Reionization 21-cm Signal Suman Majumdar Institute for - - PowerPoint PPT Presentation
Epoch of Reionization 21-cm Signal Suman Majumdar Institute for - - PowerPoint PPT Presentation
The Effect of Peculiar Velocities on the Epoch of Reionization 21-cm Signal Suman Majumdar Institute for Astronomy Stockholm University source:- arXiv:1209.4762 Collaborators o Somnath Bharadwaj (IIT Kharagpur, India) o Tirthankar Roy
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- Somnath Bharadwaj
(IIT Kharagpur, India)
- Tirthankar Roy Choudhury
(NCRA-TIFR, India)
Collaborators
- Garrelt Mellema
(Stockholm University, Sweden)
- Hannes Jensen
(Stockholm University, Sweden)
- Kanan Kumar Datta
(Stockholm University, Sweden)
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WHO? WHEN? HOW?
!!A Murder Mystery!!
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Direct Probe of Reionization Timing and duration
- f EoR
Properties of EoR Sources IGM Properties Large scale distribution of HI Physical Processes involved
HI 21-cm Radiation
!!Time Travel!!
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GMRT MWA LOFAR SKA
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Radio Interferometry
“Visibility”
= FT of Sky Brightness Temp.
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Power Spectrum of HI
“Visibility” P(k) = |A(k)|2 k = 2Π/L
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Redshift Space Distortion Line of Sight
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Redshift Space Distortion Line of Sight
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Redshift Space Distortion Line of Sight
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Redshift space distortion Line of Sight
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Power Spectrum in Redshift Space
Observed power spectrum will be LoS dependent. LoS θ k
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HR HR-RS IR IR-RS
LoS
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HR HR-RS IR IR-RS
LoS
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HR HR-RS IR IR-RS
LoS
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Our observations will always contain the effects of peculiar velocities.
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Our observations will always contain the effects of peculiar velocities.
Is that a bad news?
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Brightness Tempereture from HI Underlying Matter Density Filed + State of Hydrogen
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Brightness Tempereture from HI Underlying Matter Density Filed + State of Hydrogen Cosmology
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Brightness Tempereture from HI Underlying Matter Density Filed + State of Hydrogen Cosmology Astrophysics
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Brightness Tempereture from HI Underlying Matter Density Filed + State of Hydrogen Cosmology Astrophysics
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Angle Averaged HI Power spectrum
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Matter Power spectrum in Redshift Space
- Kaiser, N., 1987, MNRAS, 227, 1
- Hamilton, A. J. S., 1992, APJL, 385, L5
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Matter Power spectrum in Redshift Space
- Kaiser, N., 1987, MNRAS, 227, 1
- Hamilton, A. J. S., 1992, APJL, 385, L5
Legendre Polynomial
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Matter Power spectrum in Redshift Space
- Kaiser, N., 1987, MNRAS, 227, 1
- Hamilton, A. J. S., 1992, APJL, 385, L5
Angular Multipoles
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HR HR-RS IR IR-RS
LoS
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Model with Linear Approximations
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Model with Linear Approximations
Power Spectrum
- f
DM Density Field
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Model with Linear Approximations
Power Spectrum
- f
xHI Field
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Model with Linear Approximations
Cross-correlation between DM and xHI Field
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Model with Linear Approximations
- Bharadwaj, Nath and Sethi, 2001, JAA, 22, 21
- Bharadwaj and Ali, 2004, MNRAS, 352, 142
- Barkana and Loeb, 2005, ApJL, 624, L65
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Model with Linear Approximations
- Bharadwaj, Nath and Sethi, 2001, JAA, 22, 21
- Bharadwaj and Ali, 2004, MNRAS, 352, 142
- Barkana and Loeb, 2005, ApJL, 624, L65
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Our observations will always contain the effects of peculiar velocities.
It’s not a bad news!!
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Monopole (l=0) and Quadrupole (l=2)
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Monopole (l=0) and Quadrupole (l=2)
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Monopole (l=0) and Quadrupole (l=2)
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Monopole (l=0) and Quadrupole (l=2)
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Hexadecapole (l=4) ???
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Hexadecapole (l=4) ???
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