Li, TJ (reprint author), Chinese Acad Sci, Inst Theoret Phys, State Key Lab Theoret Phys, Beijing 100190, Peoples R China.
部门归属:
[Li, Tianjun
; Raza, Shabbar
; Wang, Xiao-Chuan] Chinese Acad Sci, Inst Theoret Phys, State Key Lab Theoret Phys, Beijing 100190, Peoples R China
; [Li, Tianjun
; Raza, Shabbar
; Wang, Xiao-Chuan] Chinese Acad Sci, Inst Theoret Phys, Kavli Inst Theoret Phys China, Beijing 100190, Peoples R China
; [Li, Tianjun] Univ Elect Sci & Technol China, Sch Phys Elect, Chengdu 610054, Peoples R China
; [Nanopoulos, D. V.] Texas A&M Univ, George P & Cynthia W Mitchell Inst Fundamental Ph, College Stn, TX 77843 USA
; [Nanopoulos, D. V.] Houston Adv Res Ctr, Astroparticle Phys Grp, The Woodlands, TX 77381 USA
; [Nanopoulos, D. V.] Acad Athens, Div Nat Sci, Athens 10679, Greece
英文摘要:
With the Higgs boson mass around 125 GeV and the LHC supersymmetry search constraints, we revisit a three-family Pati-Salam model from intersecting D6-branes in Type IIA string theory on the T (6)/(a"currency sign(2) x a"currency sign(2)) orientifold which has a realistic phenomenology. We systematically scan the parameter space for mu < 0 and mu > 0, and find that the gravitino mass is generically heavier than about 2 TeV for both cases due to the Higgs mass low bound 123 GeV. In particular, we identify a region of parameter space with the electroweak fine-tuning as small as Delta (EW) similar to 24-32 (3-4%). In the viable parameter space which is consistent with all the current constraints, the mass ranges for gluino, the first two-generation squarks and sleptons are respectively [3, 18] TeV, [3, 16] TeV, and [2, 7] TeV. For the third-generation sfermions, the light stop satisfying 5 sigma WMAP bounds via neutralino-stop coannihilation has mass from 0.5 to 1.2 TeV, and the light stau can be as light as 800 GeV. We also show various coannihilation and resonance scenarios through which the observed dark matter relic density is achieved. Interestingly, the certain portions of parameter space has excellent t-b-tau and b-tau Yukawa coupling unification. Three regions of parameter space are highlighted as well where the dominant component of the lightest neutralino is a bino, wino or higgsino. We discuss various scenarios in which such solutions may avoid recent astrophysical bounds in case if they satisfy or above observed relic density bounds. Prospects of finding higgsino-like neutralino in direct and indirect searches are also studied. And we display six tables of benchmark points depicting various interesting features of our model. Note that the lightest neutralino can be heavy up to 2.8 TeV, and there exists a natural region of parameter space from low-energy fine-tuning definition with heavy gluino and first two-generation squarks/sleptons, we point out that the 33 TeV and 100 TeV proton-proton colliders are indeed needed to probe our D-brane model.
