1

Direct CP violation in Dhh• World measurements of

• In New Physics: CPV up to ~1%;• If CPV ~1% were observed, is it NP or hadronic enhancement of SM?• Strategy: analyze many channels to elucidate source of CPV.• 50ab-1 BELLE-II data can reach to sensitivity of 10-3~10-4 for different

channels• Measurement of direct CPV at threshold at HIEPAF with 1ab-1 data,

sensitivity: 10-3~10-4

• clean background and better systematic control in threshold production would strengthen competitions with future B projects

No CPV observed yet in charm sector.

2

Determination of the γ angle in the CKM matrix

• ADS method: use D doubly Cabibbo-suppressed decays, e.g. D0

K+π – With 1 ab−1 at HIEPAF: σ(cosδKπ) 0.007; σ(δ∼ Kπ) 2∼ o

With this data, BELLE-II expects σ(γ) 5∼ o; upgraded LHCb: σ(γ) 1.3∼ o

• GGSZ method: use Dalitz plot analysis of 3-body D0 decays, e.g. Ks π+ π- ; high statistics; need precise Dalitz model Belle results from GSSZ method in 2012: γ=(77±15±4±4) o

HIEPAF would reduce the contribution of D Dalitz model to a comfort level of ~0.1o, since expected precision from future B projects would be ~2o.

The cleanest way to extract γ is from BDK decays: • current uncertainty σ(γ) ~10~15⁰ • however, theoretical error: 10-6 (!)• over-constrain the Unitarity TriangleInformation of D decay strong phase is needed, which can only be accessed through quantum coherence of DD production at threshold:

from D decay model

3

D–D mixing at HIEPAFcharm mixing is established!• D0 – D0 mixing rate at threshold

)])([()])([(

2

22

KKNKKNyxRM

with 1ab-1 data:RM =(x2+y2)/2 ~ 10-5 in K and Ken channelsProbe y: ΔyCP < 0.1%

While at LHCb by 2015 assuming 5 fb-1 @ 13 TeV: (x’2,y’) ± (0.004, 0.08)% with WS D0 K D0-D0 WS rate asymmetry (like |q/p|) ±1% yCP, AG ± 0.02% in D0 K-K+ and D0 - decays (x,y) ± (0.045, 0.030)% using D0 KS• Implication of strong phase

phase to relate (x’, y’) with (x, y) upgraded LHCb/BELLE-II expect statistical error

1 ab-1 D data at HIEPAF would reach to the sub-level of the above stat. errors arXiv:1209.0172

4

Asymmetric beam? charm mixing at Ψ(4040)?

Flavor tagging(D0K-l+v) Time-dependent measurement

available

Require good D z/D t resolution (SVT)

Considering Ψ(4040)DD*DDγ, DD pairs are in C-even states and charm mixing contribution is doubled compared with time-dependent (un-correlated) case.

3 ab-1 data @Ψ(3770): asymmetric γβ=0.2~0.63 ab-1 data @Ψ(4040)50 fb-1 data at upgrade LHCb50 ab-1 at BELLE-II

courtesy by Neri&RamaCPV and D mixing reach

5

D rare decays• FCNC processes:

In the SM, short distance contribution is suppressed by GIM mechanism

Long distance effect can enhance the rate to 10-6~10-7

• Lepton Flavor, Lepton Number and Baryon Number violating decays are forbidden in the SM. However, NP models can allow at sizable levels.

• HIEPAF: 10-8~10-9 stringent constrains to NP models

1 ab-1 at HIEPAF would achieve the sensitivity to 10-8~10-9. So the SM can be strictly tested away from the dilepton resonances.

HIEPAF can discriminate NP from SM by measuring: D→Vl+l− : AFB asymmetry D→Pl+l− : line shape of dilepton mass, to reveal the interference effect

between long-distance and FCNC weak amplitude (NP amplitude); expected number of events: 1~10k