1. 1 Primordial nucleosynthesis and New Physics Maxim Pospelov University of Victoria and Perimeter Institute K. Jedamzik and M. Pospelov, arXiv:0906.2087 R. Cyburt and M. Pospelov, arXiv:0906.4373

2. 2 Outline of the talk 1.Current status of Big Bang Nucleosynthesis. 2.Lithium problem. Possible solutions. 3.Particle decay/annihiliation after the BBN. 4.Catalyzed BBN. 5.Conclusions.

3. 3 BBN and Particle Physics Particle physics can 1.Affect the timing of reactions, via e.g. new thermal degrees of freedom 2.Introduce non-thermal channels e.g. via late decays or annihilations of heavy particles, E À T. 3.Provide catalyzing ingredients that change h  ijk v i (MP, 2006). Possible catalysts: electroweak scale remnants charged under U(1) or color SU(3) gauge groups. Relevant for charged NLSP-gravitino LSP scenario.

4. 4 Elemental Abundance A 12 –Stars; A=6,9,10,11 –“orphans” (cosmic ray spallation)

5. 5 BBN abundance curves n/p freeze-outDeut. bottleneckAll nuclear rates drop <Hubble

6. 6 Non-thermal change of elemental abundances due to late time energy injection

7. 7 Catalyzed Production of 6 Li and 9 Be at 8 KeV, suppression of 7 Be+ 7 Li at 35 KeV Day 1, 5:25a.m. 0:03a.m. 9 Be 6 Li

8. 8 SBBN, current Status (Cyburt, Fields, Olive 2008) Theoretical predictions of abundances as functions of  b Yellow band: WMAP- suggested input for baryon to photon ratio  b =6.14 10 -10 7 Be branch

9. 9 The fraction of energy density in baryons is measured rather precisely, No more wiggle room with  b for BBN. 2. There is a noticeable tension between predicted and observed amounts of 7 Li, A.Measurements have an unaccounted systematic error. B.We do not understand the cycling of 7 Li in stars. What we see is not primordial. C. Calculations (e.g. nuclear rates) are wrong. D. New Physics interference. What kind of new physics? 4. Unexpected 6 Li problem? Not yet... Lithium problem

10. 10 Deuterium and Lithium abundances Coc et al, ApJ 2004

11. 11 Possible astrophysical resolution of 7 Li discrepancy There is a growing suspicion that pop II stars can themselves deplete lithium by admixing it from the atmospheres into a hot interrior where it gets destroyed (Korn et al., 2006, employs diffusion and extra mixing). Can it provide a factor of 2-3 suppression? Can the suppression work uniformly along the Spite plateau, without introducing extra scatter? Would the measured abundances of other elements be OK?

12. 12 Emerging 6 Li problem? A lot of speculations about primordial 6 Li! Unexpected plateau (?) of 6 Li with metallicity (Asplund et al., 2005) 6 Li/H ~ 2 £ 10 -11

13. 13 9 Be vs metallicity There is no evidence for primordial values No serious BBN models ever predicted anything in excess of 10 -15

14. 14 More on 7 Li generation during the BBN In fact, it is 7 Li+ 7 Be that we are interested in (much later, 7 Be captures an electron and becomes 7 Li). Things are simple: there is one reaction in, and one reaction out 3 He+  ! 7 Be +  - IN. 7 Be +n ! p + 7 Li – OUT, (followed by 7 Li+p ! 2  ) At T>25 keV, 7 Li is unstable being efficiently burned by protons. 4 H e, 3 He, D, p, and n can be all considered as an input for lithium calculation. 1. 3 He and n abundances ? All reactions are too well-known. 3 He is indirectly measured by the solar neutrino flux. 2. 3 He( ,  ) 7 Be reaction is now known with better than 10% accuracy. New nuclear ways of destroying 7 Be ?

15. 15 Burning of 7 Be using deuterium It has been suggested (Coc et al., 2004) that if the reaction rate of 7 Be(d,p) ®® is arbitrarily increased by a factor of ~ 100, the lithium problem can be “solved” right during the BBN. Subsequent experimental search (Angulo et al., 2005) have shown no enhancement in this reaction. It is important, however, that the search was made at E~400 keV, and the extrapolation to BBN regime was done assuming smoothness of astrophysical S-factor (cross section). Such assumptions can be spectacularly violated by the presence of near threshold resonances ( e.g. F. Hoyle, 1950s).

16. 16 9 B energy levels from TUNL nuclear data project

17. Zooming in: 16.7 MeV resonance near 7 Be +d 17 Nothing much is known about 5/2+, 16.7 MeV +/- 100 keV resonance in 9 B. Information about mirror nucleus, 9 Be, shows that this resonance is extremely narrow. We (R. Cyburt and MP) try to determine parameters of this resonance phenomenologically, and then see if it can be consistent with nuclear physics/quantum mechanics.

18. 18 Parameters of the resonance Above the black line, 7 Li/H < 0.5 [ 7 Li/H] SBBN, and the Lithium problem is “solved”. One needs a resonance in 160-200 keV range, and Gamma > 10 keV.

19. 19 Uncertainty in 7 Li due to 9 B resonance ¡ ~10 keV is a problem because of the Coulomb screening. Such a large deuterium separation width at a resonance energy of 200 keV implies extremely large radius for the 7 Be+d interaction channel, as large as 10 fm. This is border-line of what is allowed by QM. If indeed lithium problem is solved that way, it implies “new nuclear physics”, i.e. 16.7 MeV resonance in 9 B is a 10 fm-size bound state of 7 Li and Deuteron. Being completely agnostic about properties of this resonance within QM, we arrive at the the following prediction for primordial lithium

20. 20 Enlarged error bars for 7 Li Experimental studies of the property of this resonance are required!

21. 21 Nonstandard BBN scenarios Late injection of electromagnetic/hadronic energy distorts primordial abundances, especially for those elements where the SBBN processes are extremely inefficient ( 4 He(d, ° ) 6 Li is the radiative E2 reaction, suppressed by 8 orders of magnitude relative to “normal” reactions) Energy injection with baryons in the final stay allows to circumvent this by a chain of endo-thermic but photonless reactions (Dimopoulos et al, 1980s) 4 He + p  3 H + p + p, Q=-16 MeV There is a possibility of suppressing 7 Be if O(10 -5 ) neutrons per proton are injected (Jedamzik, 2004). This also increases D/H. Typical lifetime ~ 1000 sec is required.

22. 22 BBN with energy injection decaying dark matter

23. 23 BBN with energy injection annihilating dark matter Thermal WIMP benchmark

24. 24 Catalyzed BBN Suppose that there is an electroweak scale remnant X  (and X  ), e.g. SUSY partner of electron,  or , with the following properties: 1. Masses are in excess of 100 GeV to comply with LEP/Tevatron. 2.Abundances per baryon Y X are O(0.1  0.001). In a fully specified model of particle physics they scale as Y X » (0.01  0.05)m X /TeV. 3.Decay time  X is longer than 1000 sec; no constraints on decay channels. Are there changes in elemental abundances from mere presence of X  ? Yes! Anything at all that sticks to He with binding energy between 150 KeV and 1500 KeV will lead to the catalysis of 6 Li production! Any quantities of ( 8 BeX) in excess of 10 -10 at 8 keV will lead to the catalysis of 9 Be to >10 -13 level.

25. 25 Properties of bound states ( 4 HeX  ) ( 7 BeX  ) Bohr radius is 2 times larger than nuclear Bohr orbit is within nuclear radius XX

26. 26 Recombination of 4 He and X  ( 4 HeX) bottleneck Naive equilibrium Saha-type equation gives a rapid switch from 0 to 1 at 8.3 KeV Realistic solution to Boltzmann equation leads to a gradual increase of the number of bound states. Catalyzed synthesis of 6 Li will start below 9keV

27. 27 After bound states have formed, new reaction channels open up  Main SBBN channel for 6 Li production 4 He + D ! 6 Li +  ; Q = 1.47 MeV in usual astrophysical units. 6 Li(SBBN) » 10 -14 NB: typical pre-exponents for  reactions are 10 5  10 6, for photon-less reactions 10 8  10 10  Main CBBN channel for 6 Li production ( 4 HeX  ) + D ! 6 Li + X  ; Q = 1.13 MeV

28. 28 New Reaction Channels  A possible SBBN channel for 9 Be production 8 Be + n ! 9 Be +  ; Q = 1.66 MeV 9 Be(SBBN) » 10 -18  Main CBBN channel for 9 Be production ( 8 BeX  ) + n ! 9 Be + X  ; Q = 0.26 MeV This is a large photonless rate dominated by threshold resonance!

29. 29 6 Li and 9 Be at 8 KeV CBBN with Y X = 5 £ 10  3,  X = 1 as a typical example, resulting in 6 Li >10 -8, and 9 Be>10 -11 – Excluded! Observationally, 6 Li/H < few £ 10 -11 ; 9 Be/H<few £ 10 -13, Therefore, Y X (2 £ 10 4 sec) < 10 -5, and typically  X < 5 £ 10 3 s.

30. 30 6 Li and 9 Be at 8 KeV CBBN with Y X = 10  1,  X =2000s as a “just so” scenario 6 Li/H=1.3 £ 10 -11 ; 9 Be/H=7 £ 10 -14 : A very intriguing pattern!!! 9 Be/ 6 Li = (2-5) £ 10 -3 - a typical “footprint” of CBBN

31. 31 Constraints on particle physics models Type I: X  ! SM  [X 0 ],  E » M X. Longevity because of small couplings. Examples: NLSP slepton (stau, smuon...) ! Gravitino LSP NLSP slepton (stau, smuon...) ! "Dirac" RH sneutrino LSP Long-lived EW scale triplet Higgs decaying to SM Type I requires taking care of "nonthermal" BBN effects. Type II: X  ! X 0 + e  [ ];  E » few MeV or less. Longevity because of the small energy release. Examples: Closely degenerate stau-neutralino system Closely degenerate chargino-neutralino (O(MeV) splitting) Dark matter as heavy EW multiplet (O(MeV) splitting) Before CBBN, models of Type II were believed to be unconstrained by physics of the Early Universe.

32. 32 Catalytic suppression of 7 Be + 7 Li  The “bottleneck” is creation of ( 7 BeX  ) bound states that is controlled by 7 Be+X  ! ( 7 BeX  ) +  reaction  There are two main destruction channels that are catalyzed: 1. p-reaction: ( 7 BeX  ) + p ! ( 8 BX  ) +  by a factor of >1000 relative to 7 Be + p ! 8 B +  2. In models with weak current, the “capture” of X  is catalyzed: ( 7 BeX  ) ! 7 Li + X 0, so that lifetime of ( 7 BeX  ) becomes ¿ 1 sec. 7 Li is significantly more fragile and is destroyed by protons “on the spot”. 3.There is significant energy injection via X  +X  ! (X  X  ) ! radiation. If this process has hadronic modes, it also affects Li7. 4. Combination of 6 Li and 7 Li constraints indicates the lifetime 1000-2000 s.

33. 33 How likely is such scenario? (SUSY landscape ? :) Suppose nature chose the weak scale supersymmetry. There are two types of regular superpartners: Neutrals: neutralinos, sneutrinos. Charged: charged sleptons, squarks, charginos All masses are at ~ TeV or less [one would hope!] “Probability” of m lightest charged < m lightest neutral : 50% Gravitino mass is a free parameter, not linked to weak scale “Probability” of m gravitino <m lightest charged < m lightest neutral : 25% In 25% cases SUSY models would have long-lived charged or strongly interacting relics!

34. 34 Conclusions 1.Lithium problem is a serious discrepancy between SBBN prediction and Spite plateau value of 7 Li abundance. Possibly indicates A. new delicate processes in the atmospheres of pop II stars, B. New nuclear physics channels (easy to check), C. New particles that catalyze 7 Be destruction. Or the combination of the above. Last option is generally testable at LHC. 2.Energy injection via decay/annihilation of heavy relics is testable with BBN, especially in the channels that are accidentally suppressed in the standard scenario: 6 Li, 9 Be. 3.Catalysis of nuclear fusion is a new generic mechanism of how particle physics can affect the BBN predictions for lithium and beryllium. CBBN imposes important constraints on particle physics models that cannot be [yet] probed in other ways; this includes some TeV-scale SUSY models. 6 Li and 9 Be abundances are drastically enhanced, with ratio 6 Li/ 9 Be = (2-5) £ 10 -3, affected by mere presence of charged particles during BNN. 7 Li+ 7 Be can be suppressed by a factor of ~ 2.