Searches for non-SM Higgs
at the Tevatron

Andy Haas

Columbia University

on behalf of the
DØ and CDF Collaborations

Moriond EW 2008

Outline

MSSM Higgs

(h/H,A)→ττ

b(h/H,A)→bbb

b(h/H,A)→bττ

Triplet Models

H++

Fermiophobic Higgs

h→ γγ

h+V→ γγ+X

Prospects

>3.5 fb-1 delivered!

Most results here: 1-2 fb-1

Higgs Bosons in the MSSM

Two Higgs doublet fields

Hu(Hd) couple to up(down)-type fermions

tanβ = <Hu>/<Hd>

5 particles after EWSB

h, H, A, H+, H-

h must be light, <~135 GeV

At large tanβ, coupling of A, h/H to down-type fermions (b, τ) is enhanced

Cross-section proportional to tan2β

Branching ratio: bb~90%, ττ~10%

b(h/H,A)→bbb

(h/H,A)→bb swamped by QCD background

Look for associated b production

Require at least 3 b-tagged jets

Signal:

Invariant mass of leading jets is peaked at mA

Backgrounds (determined from data):

Shape based on the double
b-tagged data sample

Corrected for kinematic bias
from the 3rd b-tag

Events with >=3
b-tagged jets

0.9 fb-1

Inv. mass of leading jets (GeV)

(mA=120, tanβ=60)

b(h/H,A)→bττ

344 pb-1 (update in progress!)

Best S/B of all three MSSM analyses, but lowest cross-section x BR

Select ττ(→μ) events, normalize to Z→ττ peak

Require >=1 b-tagged jet, with pT>15 GeV

Multijet (QCD) background measured using like-sign data

single-π-like τ

rho-like τ

3-prong τ

MSSM Higgs Limits

D0 Run IIa (344/pb)

D0 Run IIa (344/pb)

bH→bbb

bH→bττ

H++

Models with H++

Left-right symmetric models

Higgs triplet

Little Higgs

Analysis Overview

1.1 fb-1

3 ’s with:
PT>15 GeV
||<2.0

>=1  pair with:
M>30 GeV/c2;
<2.5 rad

Results

Background: 3.10.5

Data: 3 events

Result:

HR > 127 GeV

HL > 150 GeV

H→γγ

Could be large H→γγ BR: “fermiophobic”

Top-color models

LED theories

MSSM: Hbb suppressed by 1-loop corrections

Select 2 isolated photons, ET>25 GeV

QCD jet fakes estimated using the shower-shape correlations between
the 2 photons (“matrix method”)

Also contributes to SM Higgs search!

H+V→γγ+X

Associated Fermiophobic Higgs

Analysis overview

1.1 fb-1;

2 ’s with: ET>25 GeV, ||<1.1, M>65 GeV

Two regions

Signal: qT>35 GeV

Control: qT<35 GeV

Backgrounds: , j, jj

LEP: mH>109.7 GeV

Prospects

Results from the first 1-2/fb of data show very promising sensitivity

Expect up to 6 fb-1 by 2009

Exclude

up to mA~250 GeV for high tanβ

down to tanβ~20 for low mA

Or make a discovery!

Backup

Tau ID

Dmitri Denisov, ICHEP04, August 21 2004

Andy Haas

2004-07-07T15:59:13