Download presentation
Presentation is loading. Please wait.
Published byIrwan Pranoto Modified over 5 years ago
1
PROBING THE UNIVERSE AT 20 MINUTES AND 400 THOUSAND YEARS
Gary Steigman Ohio State University SUSY 06, Irvine, CA, June 12 – 17, 2006
2
Primordial Nucleosynthesis Relic Photons (CBR) are free
~ 100 s after the Big Bang Primordial Nucleosynthesis ~ 0.1 s after the Big Bang Neutrinos Decouple ~ 380 kyr after the Big Bang Relic Photons (CBR) are free
3
BBN & The CBR Provide Complementary Probes Of The Early Universe
Do the predictions and observations of the baryon density (10 (nB/nγ)0 = Bh2 ) and the expansion rate (H) of the Universe agree at 20 minutes (BBN) and at kyr (CBR) ?
4
D, 3He, 7Li are potential BARYOMETERS
BBN – Predicted Primordial Abundances BBN Abundances of D, 3He, 7Li are RATE (Density) LIMITED 7Li 7Be D, 3He, 7Li are potential BARYOMETERS
5
DEUTERIUM --- The Baryometer Of Choice
As the Universe evolves, D is only DESTROYED * Anywhere, Anytime : (D/H) t (D/H) P * For Z << Z : (D/H) t (D/H) P (Deuterium Plateau) (D/H) P is sensitive to the baryon density ( ) H and D are seen in Absorption, BUT … * H and D spectra are identical H Interlopers? * Unresolved velocity structure Errors in N(H ) ?
6
D/H vs. Metallicity Deuterium Plateau ? Real variations,
systematic differences, statistical uncertainties ? LLS Deuterium Plateau ? DLA Low – Z / High – z QSOALS
7
For Primordial D/H adopt dispersion around the mean
D/H vs. Metallicity For Primordial D/H adopt the mean and the dispersion around the mean 105(D/H)P = 2.6 ± 0.4
8
(D/H)P = 0.4 x 10 SBBN 10 = 0.6 BBN
9
CBR
10
CBR Temperature Anisotropy Spectrum (2003)
(T2 vs. ) Depends On The Baryon Density Barger et al. (2003) B h2 = , , CBR (WMAP) constrains B h2 The CBR is an early - Universe Baryometer
11
CBR (WMAP – ALONE) 10 = 0.3 CBR
12
D/H vs. Metallicity The CBR is a good Deuteronometer ! SBBN/WMAP
105(D/H)P = 2.6 ± 0.2
13
BBN (20 min) & CBR (380 kyr) AGREE !
14
S (or N) is constrained by YP
The Expansion Rate (H) Provides A Probe Of Non-Standard Physics 4He production is n/p Limited YP is sensitive to the EXPANSION RATE ( H 1/2 ) S H / H (/)1/2 (1 + 7N / 43)1/2 where + N and N 3 + N S (or N) is constrained by YP
15
4He is an early – Universe Chronometer
Y vs. D / H N = 2, 3, 4 (S = 0.91, 1.00, 1.08) Y N (S – 1)
16
D & 4He Isoabundance Contours
YP & yD 105 (D/H) 4.0 3.0 2.0 0.25 0.24 0.23 D & 4He Isoabundance Contours Kneller & Steigman (2004)
17
"2σ" range for YP : 0.228 0.248 (OSW) As O/H 0, Y 0
SBBN Prediction "2σ" range for YP : (OSW)
18
BBN (D, 4He) For N ≈ 2.5 ± 0.3 YP & yD 105 (D/H) 4.0 3.0 2.0 0.25
0.24 0.23
19
A Non-Standard BBN Example (Neff < 3) Late Decay of a
Massive Particle Kawasaki, Kohri & Sugiyama & Low Reheat Temp. (TR MeV) Neff < 3 Relic Neutrinos Not Fully (Re) Populated
20
BBN and Primordial (Pop ) Lithium ? Li/H vs. Fe/H
Li too low ? SBBN + CBR log (Li) 2.6 – 2.7 “Spite” Plateau (?) log (Li) 2.2
21
log (Li) 2.6 0.1 Or, Late Decay of the NLSP ? Even for N 3
yLi 1010 (Li/H) 4.2 YOSW + D H Li H 0.8 x 10 10 log (Li) 2.6 0.1 Li depleted / diluted in Pop stars ? Or, Late Decay of the NLSP ?
22
CBR Temperature Anisotropy Spectrum (2003)
Depends on the Radiation Density R (S or N) N = 1, 2.75, 5, 7 Barger et al. (2003) CBR (WMAP) constrains N (S) The CBR is an early - Universe Chronometer
23
BBN (D & 4He) + CBR (WMAP – 2003)
BBN & CBR Consistent ! CBR BBN Barger et al. (2003) Barger et al. (2003)
24
Joint BBN (D & 4He) & CBR (WMAP) Fit
Barger et al. (2003) Barger et al. (2003)
25
Baryon Density Determinations: Consistent ?
Late - Decaying NLSP ? ? N < 3 ? Observational Uncertainties Or New Physics?
26
N Determinations (95 % CL Ranges)
(v.1) WMAP 2006 WMAP 2003
27
Seljak et al. Revised BUT ! N > 3 ! (v.2)
28
VERY PRELIMINARY ! STAY TUNED ! N & Mh2 Are Correlated
V. Simha & G. S. N & Mh2 Are Correlated 2 ≤ N ≤ 8 ? VERY PRELIMINARY ! STAY TUNED ! The CMB Is A Relatively Poor Chronometer
29
BBN (~ 20 min.) And The CBR (~ 400 kyr)
CONCLUSIONS (Pre – WMAP 2006) BBN (~ 20 min.) And The CBR (~ 400 kyr) Are CONSISTENT ! 1.9 ≤ N ≤ allowed @ ~ 95% ( Also : 10 = ± 0.2 )
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.