What Atomic Physics Can Do for Neutrino and Direct Dark Matter Detection?

1. What Atomic Physics Can Do for Neutrino and Direct Dark           Matter Detection? Jiunn-Wei Chen National Taiwan U. Collaborators: Chih-Liang Wu, Chih-Pang Wu (NTU) Chen-Pang Liu, Hsin-Chang Chih (NDHU) Keh-Ning Huang, Hao-Tse Shiao, Hao-Bin Li, Henry T. Wong, Lakhwinder Singh (AS)

2. Neutrino and Dark Matter are Portals to New Physics

4. Neutrino: Challenges and Opportunities • Mass: hierarchy and absolute values • Dirac or Majorana? • CP phase(s) • Sterile neutrinos? • Electromagnetic properties: magnetic moments? Charge Radius?... Those are probes of new physics!

5. l W ni nj ni nj W l g g How neutrino magnetic momentarises in SM?

6. Dirac Majorana Neutrino Magnetic Moment (NMM) Flavor changing MM Flavor unchanging MM ○ ○ × (forbiden by CTP) ○ A probe of new physics!

7. Dark Matter (DM) • Bigger density than the visible Universe • Its existence hints that there might be a dark sector

8. Portals to the Dark Sector • Other dark matter candidates include MACHOs: MAssive Compact Halo Objects WIMPs: Weakly Interacting Massive Particles

10. Why Atomic Physics? • Energy scales: Atomic (~ eV) Reactor neutrino (~ MeV) WIMP (~ GeV) • Neutrino: NNM atomic ionization signal larger at lower energy scattering (current Ge detector threshold 0.1 keV) • DM: direct detection, velocity slow (~ 1/1000), max energy 1 keV for mass 1 GeV DM. • Opportunity: Applying atomic physics at keV (low for nuclear physics but high for atomic physics)

11. Neutrino Atomic Ionization • The complete set of neutrino electromagnetic form factor is can be constrained:

12. Weak Interaction Magnetic moment scattering Should go for low T (energy transfered)!

13. Two Approximations ---I Equivalent Photon Approx. • proposed by Henry Wong et al. ( PRL 105 061801) • photon q2～0 : relativistic beam or soft photons qμ～0 • several orders of magnitude enhancement • → tighen the μν constraint with the same set of data

14. Two Approximations --- II Free Electron Approx. • revisited by Voloshin et al. ( PRL 105 201801) • sum rule and Hydrogen-like calculation • FEA works well at sub-keV regime

15. Toy: ν-H atomic ionization, exact result obtained (1307.2857)

16. Toy: ν-H atomic ionization, exact result obtained (1307.2857)

17. Two Approximations Free Electron Approx. (revisited by Voloshin et.al) Equivalent Photon Approx. ↓ binding momentum of hydrogen: αme

18. MCRRPA: multiconfiguration relativistic random phase approx. Ge atomic ionization: ab initio MCRRPA Theory Hartree-Fock : Reducing the N-body problem to a 1-body problem by solving the 1-body effective potential self consistently. ↓ RPA: Including 2 particle 2 hole excitations ↓ RRPA: Correcting the relativistic effect ↓ MCRRPA: More than one configurations in Hartree-Fock; Important for open shell system like Ge where the energy gap is smaller than the closed shell case

19. MCRRPA Theory N-electron relativistic Hamiltonian ↓ ↓ Dirac Hamiltonian + Coulomb interaction The rest of EM interaction ↓ ↓ Solve final wavefunction by time evolution Solve initial wavefucntion of atom

20. Benchmark: Ge Photoionization Exp. data: Ge solid Theory: Ge atom (gas) Above 100 eV error under 5%. JWC et. al. arXiv: 1311.5294

21. Ge atomic ionization withab initio MCRRPA Theory JWC et. al. arXiv: 1311.5294

22. Ge atomic ionization withab initio MCRRPA Theory JWC et. al. arXiv: 1311.5294

23. Ge atomic ionization withab initio MCRRPA Theory JWC et. al. 1411.0574

24. JWC et. al. arXiv: 1411.0574

25. Direct Dark Matter Detection RPP 2014

26. What Can Atomic Physics Contribute? • Light dark matter detection: • Electron recoil background from solar neutrinos for a LXe detector • Large LXe detectors can be used as a neutrino/axion detectors as well (measuring NNM w/ a source nearby)

27. Electron Recoil Background for DARWIN (Lxe) L. Baudis et al 1309.7024

28. Summary • Neutrinos and dark matter particles are portals to new physics • Ab initio calculations of Ge neutrino atomic ionization performed with 5-10% estimated error. Xe can be done as well. • Ongoing: dark matter atomic ionization

29. Searching for the QCD Critical End Point Jiunn-Wei Chen National Taiwan U. JWC, Jian Deng, Lance Labun 1410.5454

30. Universality • In the scaling region, physics is the same within the same universality class---an effective field theory argument. • QCD near CEP ~ Ising model (Stephanov)

31. 4th moment CPOD 2014

32. 3rd moment CPOD 2014

33. When the Imaginary is a Real Alternative Jiunn-Wei Chen National Taiwan U. Phys.Rev.Lett. 110 (2013) 262301 Collaborators: Jens Braun, Jian Deng, Joaquin E. Drut, Bengt Friman, Chen-Te Ma, Yu-Dai Tsai

34. From the hottest to the coolest, and back?

35. When Mr. Berry Meets Mr. Wigner Jiunn-Wei Chen National Taiwan U. JWC, Shi Pu, Qun Wang, Xin-Nian Wang Phys.Rev.Lett. 110 (2013) 262301

36. Flavor Structure of the Nucleon Sea from Lattice QCD Jiunn-Wei Chen National Taiwan U. arXiv:1402.1462 [hep-ph] Collaborators: Huey-Wen Lin, Saul D. Cohen, Xiangdong Ji

38. Backup slides

39. Solar Neutrino Flux

40. Case study: NMM • Reactor antineutrino ( ) GEMMA : Ge detector with threshold 1.5keV TEXONO: Ge detector with threshold 5keV • Solar neutrino Borexino • Astrophysicallimit (model dependent)

41. Weak Interaction Magnetic moment scattering

42. How low islow enough? Now sub-keV Ge detector is available!

44. Parton Physics on a Euclidean LatticeX. Ji, PRL, 2013

45. Schematic QCD Phase Diagram The location of the critical point (CEP)is still unknown. Th: Difficult to apply LQCD to the low T / high chemical potential region.

46. Our ContributionJWC, Jian Deng, Lance Labun,1410.5454 • Work out the mapping in a simple model: 1+1dim Gross-Neveu model in the large N limit. Not in the same universality class---different critical exponents but behavior similar. • More diagrams not included are also important in the power counting: