understanding the matter-antimatter asymmetry of the ...what do we know about matter and antimatter...

Understanding the Matter-AntimatterAsymmetry of the Universe

Search for the Origin of Mass - the God Particle

Romulus GodangThe University of Mississippi

January 30, 2007Oxford, Mississippi

January 30, 2007

Oxford, Mississippi

Understanding the Matter-Antimatter Asymmetry of the Universe (page 1)


Romulus Godang

The University of Mississippi

Fundamental Particle

� What is the world made of ?

• In ancient times, people sought to organize the world

into fundamental elements: earth, air, fire, and water.

. Who first classified these fundamental elements ?

↪→ Greek thinker Empedocles (500 BC)

• Are they really the fundamental elements ?

January 30, 2007

Oxford, Mississippi



Romulus Godang


Fundamental Particle ...

� The ancient Chinese believed 5 basic elements:

• Wood

• Metal

• Earth

• Fire

• Water

� The ancient India proclaimed 5 basic elements:

• Space

• Air

• Fire

• Water

• Earth

January 30, 2007

Oxford, Mississippi



Romulus Godang


Is the Atom or Nucleus Fundamental ?

� Fundamental building blocks mean objects that are simple and structureless

� Scientists originally thought the nucleus was fundamental BUT

later they discovered that nucleus was made of protons and neutrons

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Birth of the Universe

� After the Big bang exploded with enormous energy, the universe beganto cool-down that has lasted until our own time

� BUT we don’t know what made the Big Bang happen in the first place

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Standard Model Theory

� All the known matter particles are composites of 6 quarks and 6 leptons

and they interact by exchanging force carrier particles:

↪→ Electromagnetic (γ), Weak (Z0, W±), and Strong (gluons)

↪→ Gravity (not yet in the model...)

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Standard Model Theory...

� Hadrons are composite particles made of quarks:

• Baryons are any hadron which is made of three quarks (qqq)

↪→ proton (uud) and antiproton (uud)

• Mesons contain one quark (q) and one antiquark (q)

↪→ B0 (db) and B0 (db)

January 30, 2007

Oxford, Mississippi



Romulus Godang


Looking for New Particles

� All new particles are named with Greek letters

� We have discovered about 200 particles

� Enrico Fermi (Nobel 1938) said to his student

Leon Lederman (Nobel 1988): ”Young man, if

I could remember the names of these particles,

I would have been a botanist!”

� All measurements are combined and listed in one book by

Particle Data Group (PDG) at Berkeley University.

� PDG is an international collaboration charged with summarizing Particle Physics

and related areas of Cosmology and Astrophysics since 1957.

� 2006 PDG published 1200-page book, all years it has been cited in 24,000 times

� U. Miss has significantly contributed to and member of PDG (R. Godang)

January 30, 2007

Oxford, Mississippi



Romulus Godang


http://pdg.lbl.gov/

http://www.phy.olemiss.edu/~godang/godang_PDG_consultants.pdf

What Do We Know about Matter and Antimatter ?

� Antimatter is a mirror image of matter

• Particle and antiparticle have identical mass and spin BUT opposite charges

Neutral bosons (e.g. Z0, γ) have their own antiparticles

� The antimatter introduced by Paul Dirac (Nobel Prize 1933) in 1928

Dirac’s equation ↪→ electron with ± energy

1932 Carl Anderson discovered the positron in a cloud chamber

Frederic and Irene Curie found positrons emission

� The Big Bang produced matter and antimatter in equal numbers

� Our universe is the absence of antimatter (we live in a universe of matter)

� What happened to the antimatter...?

January 30, 2007

Oxford, Mississippi



Romulus Godang


What Happened to the Antimatter ?

� How do we know there is no antimatter around ?

• When a matter and antimatter meet, they annihilate into pure energy,

leaving only photons and neutrinos

• The fact: we don’t see this kind of energy in our daily life

� Can we see the evidence of antimatter ?

� The magnetic field makes negative particles curl left, positive particles curl right

January 30, 2007

Oxford, Mississippi



Romulus Godang


Why the Universe is Made Exclusively of Matter ?

� Andrei Sakharov (1967):

• Baryon violating interactions

• Thermal non-equilibrium situation

• CP violation

� Testing the Sakharov’s criteria:

• There is no direct evidence that baryon number is violated

• There is a prediction of proton decay: p→ e+ + π0

but the predicted proton lifetime is ∼ 1030 year (not observed)

• In thermal equilibrium the particle density depends only on

the particle mass and temperature.

They are identical in CPT theorem ↪→ NO asymmetry

January 30, 2007

Oxford, Mississippi



Romulus Godang


CP Violation in Weak Interaction

� C (Charge Conjugation Invariance)

• Charge conjugation invariance is broken in weak interaction

• Right-handed neutrinos (left-handed antineutrinos) are not seen

� P (Parity) = the flip in the sign of all spatial coordinates

• Parity is broken in weak interaction

• There is no left-handed antiparticles

� CP: Charge Conjugation with Parity Invariance

• CP is conserved in weak interaction (left-handed neutrino) but...

Christension, Cronin, Fitch and Turlay have discovered CP violation

in Kaon system (1964) ↪→ confirmed by KTEV (Fermilab) and NA48 (CERN)

January 30, 2007

Oxford, Mississippi



Romulus Godang


The B Meson Factories

� BABAR at Stanford Linear Accelerator Center

� Another B-factory machine is at KEKB (Tsukuba) in Japan

January 30, 2007

Oxford, Mississippi



Romulus Godang


CP Violation in B Meson

� BABAR and Belle directly measured CP violation in B system

BABAR : e+ (3.1 GeV) - e− (9 GeV) Belle : e+ (3.5 GeV) - e− (8 GeV)

In 1999 BABAR and Belle had first colliding beam

In 2001 BABAR and Belle reported the first measurement of direct

CP violation in B meson ↪→ fundamental matter-antimatter asymmetry

January 30, 2007

Oxford, Mississippi



Romulus Godang


The BABAR Collaboration

U. Mississippi group: L. Cremaldi, V. Eschenburg, R. Godang, R. Kroeger

J. Reidy, D. Sanders, D. Summers, and H. Zhao

January 30, 2007

Oxford, Mississippi



Romulus Godang


Physics at B Factories

d

d

b

−e

+e

b

B0

B0

γ∗ϒ(4S)

9.44 9.46

Mass (GeV/c2)

0

5

10

15

20

25

σ (e

+e- →

Had

rons

)(nb

) ϒ(1S)

10.00 10.020

5

10

15

20

25

ϒ(2S)

10.34 10.370

5

10

15

20

25

ϒ(3S)

10.54 10.58 10.620

5

10

15

20

25

ϒ(4S)

� All B physics based on Υ (4S) decays including CP violation measurement

� U. Miss published B(Υ (4S)→ B0B0) in PRL 95, 042001, 2005 (R. Godang)

B(Υ (4S)→ B0B0) ≡ f00 = 0.487± 0.010stat ± 0.008syst

-8 -6 -4 -2 0 2 M2ν (GeV2/c4)

0

20000

40000

60000

80000

100000

120000

Can

dida

tes/

(0.1

7 G

eV2 /c

4 )

data, single tags

B- 0 signal

BB- peaking

BB- combinatoric

-8 -6 -4 -2 0 20

100

200

300

400

500

600

M22ν (GeV2/c4)

Can

dida

tes/

(0.1

7 G

eV2 /c

4 )

data, double tags

B- 0 signal

BB- peaking

BB- combinatoric

January 30, 2007

Oxford, Mississippi



Romulus Godang


The CKM Matrix

� In SM, quark can change flavor by weak interactions:

d′

s′

b′

=

Vud Vus VubVcd Vcs VcbVtd Vts Vtb

dsb

Cabibbo-Kobayashi-Maskawa (CKM) matrix

[Weak eigenstates] = [VCKM ] [quark mass eigenstates]

The CKM matrix contains real and imaginary numbers (complex numbers)

• Wolfenstein’s CKM matrix form:

VCKM =

1− 12λ2 λ Aλ3(ρ− iη)

−λ 1− 12λ2 Aλ2

Aλ3(1− ρ− iη) −Aλ2 1

• Four independent parameters: A, ρ, η, and λ ∼ 0.22 (expansion parameter)

• A, ρ, η are real numbers and can be measured in B decays

January 30, 2007

Oxford, Mississippi



Romulus Godang


The CKM Matrix...

� By applying the unitarity condition (scalar product of any two rows or columns):

V ∗ubVud + V ∗cbVcd + V ∗tbVtd = 0

� CKM matrix can be presented by a triangle in the complex plane

B KSψ

B π π+ -

B ργB

0 B

0mixing

BS ρKS

B+

Dcp0 K

+

B ππ, Κπl

V

V

V Vtd tb

ud

ub

V Vcd cb*

**

γ

α

β

b u ν

b c ν

l

• It is very important to measure the CKM angles and its sides!

• We need to measure them precisely in order to search for New Physics

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Unitarity Triangle (UT)

� The UT sides Ru and Rt can be expressed:

R t

(ρ,η)

γ

α

βρ

η

Ru

(0,0) (1,0)

Ru =

∣∣∣∣VudV

∗ub

VcdV∗cb

∣∣∣∣ =

√ρ2 + η2 Rt =

∣∣∣∣VtdV

∗tb

VcdV∗cb

∣∣∣∣ =

√(1− ρ)2 + η2

� The angles α, β, and γ are defined by

α = arg

[− VtdV

∗tb

VudV∗ub

], β = arg

[−VcdV

∗cb

VtdV∗tb

], γ = arg

[−VudV

∗ub

VcdV∗cb

]

� B factories and other experiments measure (α = π − β − γ)

cosγ = ρ/Ru , sinγ = η/Ru

cosβ = (1− ρ)/Rt , sinβ = η/Rt

January 30, 2007

Oxford, Mississippi



Romulus Godang


How to Measure the UT

� The Unitarity Triangle plane for the relevant observables:

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

-2 -1.5 -1 -0.5 0 0.5 1 1.5 2

εK

εK

K0→π0νν

ε,/εK , K0

L→π0νν

∆md

|Vub/Vcb|

sin 2α

sin 2α

sin 2β

sin 2β

K+→π+νν

K+→π+νν

sin γ sin γ

ρ

ηα

βγ

� Sin 2β (CP violation) measurement is the main goal of BABAR and Belle

� Surprisingly BABAR and Belle discovered several other new particles:

massive particle Y(4260) (2005) and Ds (2317) (2003)

January 30, 2007

Oxford, Mississippi



Romulus Godang


CP Violation in B System

� The time evolving B0 or B0 to its final CP eigenstates:

afCP =Γ(B0

phys(t)→fCP )−Γ(B0phys(t)→fCP )

Γ(B0phys(t)→fCP )+Γ(B0

phys(t)→fCP )

afCP =1−|λfCP |2cos(∆mB t)−2=mλfCP sin(∆mB t)

1+|λfCP |2

where: λfCP = qp

AfCPAfCP

, AfCP = amplitude of final CP eigenstates

qp

= −∆mB− i2 ∆ΓB

2(M12− i2 Γ12), where p and q are the complex coefficients

� There are 3 ways to measure CP Violation in B decays:

• Direct CP violation in B decays (B0 and B± decays)

| AfCPAfCP

| 6= 1

• CP violation in pure mixing (only B0 decays)

| qp| 6= 1

• CP violation in the interference between decays with or without mixing

|λfCP | = 1,=m(λfCP ) 6= 1

January 30, 2007

Oxford, Mississippi



Romulus Godang


CP Violation in B System...

January 30, 2007

Oxford, Mississippi



Romulus Godang


How to measure CP Violation in B System

� The time-dependent CP violation asymmetry:

ACP (∆t) ≡ f+(∆t)− f−(∆t)

f+(∆t) + f−(∆t)

= −ηf sin2β sin (∆md ∆t),

where

ηf = ±1, CP eigenvalue of the final state f

∆md = the B0 −B0 oscillation frequency

∆t = trec − ttag, βγ = 0.56, ∆z ≈ βγc∆t|∆z| = βγcτB0 ≈ 250µm

� β = arg[−VcdV ∗cbVtdV ∗tb

]

β is the angle of the UT of the CKM matrix

� The direct measurement of sin2β is the CP asymmetry

January 30, 2007

Oxford, Mississippi



Romulus Godang


CP Violation Result

� The number of B0(NB0) and B0(NB0) tags

� The asymmetry (NB0 −NB0)/(NB0 +NB0) as a function of ∆t

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Current CP Violation Status

ACP Averages

HF

AG

Jan

2006

HF

AG

Jan

2006

HF

AG

Jan

2006

HF

AG

Jan

2006

HF

AG

Jan

2006

HF

AG

Jan

2006

DC

P K

AC

P+

DC

P K

AC

P-

D* C

P K

AC

P+

D* C

P K

AC

P-

DC

P K

* A

CP

+

DC

P K

* A

CP

-

-1.4 -1.2 -1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1 1.2 1.4

BaBar 0.35 ± 0.13 ± 0.04

Belle 0.07 ± 0.14 ± 0.06

Average 0.23 ± 0.10

BaBar -0.06 ± 0.13 ± 0.04

Belle -0.11 ± 0.14 ± 0.05

Average -0.08 ± 0.10

BaBar -0.10 ± 0.23 +-00..0034

Belle -0.27 ± 0.25 ± 0.04

Average -0.18 ± 0.17

Belle 0.26 ± 0.26 ± 0.03

Average 0.26 ± 0.26

BaBar -0.08 ± 0.19 ± 0.08

Belle -0.02 ± 0.33 ± 0.07

Average -0.06 ± 0.18

BaBar -0.26 ± 0.40 ± 0.12

Belle 0.19 ± 0.50 ± 0.04

Average -0.08 ± 0.32

H F A GH F A GJan 2006

PRELIMINARY

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Current CP Violation Status...

sin(2βeff)/sin(2φe1ff)

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

HF

AG

HE

P 2

005

b→ccs

φ K

0η′

K0

f 0 K

S

π0 KS

π0 π0 K

S

ω K

S

K+ K

- K0

KS K

S K

S

-3 -2 -1 0 1 2 3

World Average 0.69 ± 0.03BaBar 0.50 ± 0.25 +-

00..0074

Belle 0.44 ± 0.27 ± 0.05Average 0.47 ± 0.19BaBar 0.36 ± 0.13 ± 0.03Belle 0.62 ± 0.12 ± 0.04Average 0.50 ± 0.09BaBar 0.95 +-

00..2332 ± 0.10

Belle 0.47 ± 0.36 ± 0.08Average 0.75 ± 0.24BaBar 0.35 +-

00..3303 ± 0.04

Belle 0.22 ± 0.47 ± 0.08Average 0.31 ± 0.26BaBar -0.84 ± 0.71 ± 0.08Average -0.84 ± 0.71BaBar 0.50 +-

00..3348 ± 0.02

Belle 0.95 ± 0.53 +-00..1125

Average 0.63 ± 0.30BaBar 0.41 ± 0.18 ± 0.07 ± 0.11Belle 0.60 ± 0.18 ± 0.04 +-

00..1192

Average 0.51 ± 0.14 +-00..1018

BaBar 0.63 +-00..2382 ± 0.04

Belle 0.58 ± 0.36 ± 0.08Average 0.61 ± 0.23

H F A GH F A GHEP 2005

PRELIMINARY

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Unitarity Triangle Sides

� B factories has improved our understanding of CP violation :

♦ sin 2β = 0.687± 0.032 (a precision measurement of 4.7%)

↪→ This precision outstripped the other measurements

� As for today measurements |Vub| and |Vcb| are complementary to sin 2β

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

-0.4 -0.2 0 0.2 0.4 0.6 0.8 1

excluded at CL > 0.95

γ

α


sin 2β

sol. w/ cos 2β < 0(excl. at CL > 0.95)

α

βγ

ρ

η

excl

uded

are

a ha

s C

L > 0.95 C K M

f i t t e rEPS 2005

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

-0.4 -0.2 0 0.2 0.4 0.6 0.8 1


α

∆md

εK

γ ∆ms & ∆md

|Vub/Vcb|


sin 2β

sol. w/ cos 2β < 0(excl. at CL > 0.95)

α

βγ

ρ

η

excl

uded

are

a ha

s C

L > 0.95 C K M

f i t t e rEPS 2005

♦ Using only angle measurements ♦Without angle measurements

� It is clear that we have to make the green ring ( |Vub||Vcb| ) thinner

in order to make a stringent test on the Standard Model

� We need to improve a precision of |Vub| (especially) and |Vcb|

January 30, 2007

Oxford, Mississippi



Romulus Godang


Semileptonic B Decays

♦ Why do we use semileptonic B Decays ?

�

� ��

��

�

��

� Simple theoretical description at parton level

� B flavor can be identified from charge of lepton

� Coupling at W− is proportional to |Vub| and |Vcb|which is directly related in its decay rate :

• Γ(b→ u`ν) =G2F

192π2 |Vub|2m5b

• Γ(b→ c`ν) =G2F

192π2 |Vcb|2m2b(mb −mc)

3

♦ Experimental Approaches :

� Sensitive to strong interactions in B decays

• Exclusive measurements

need form factors to describe the B transition

• Inclusive measurements

need Operator Product Expansion (OPE) and b mass to extract |Vxb|

�

��

��

�

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Unitarity Triangle Status

� The current average angle results:

α = (92.1± 5.1)◦; β = (24.6± 1.7)◦; γ = (63.1±5.0)◦

� A precision measurement of |Vub||Vcb| would significantly improve

the constraints on the Unitary Triangle in SM

=⇒ It could benchmark for New Physics

� Current precision of |Vub| and |Vcb| measurements :

• (∆|Vub||Vub| ) = (3.3exp ± 2.9model ± 4.7SF ± 4.0th)% = 7.6%

• (∆|Vcb||Vcb| ) = 2%. (OPE fit of E` and MX moments by BABAR )

=⇒ It contributes directly to a precision of (∆|Vtd||Vtd| )

� BABAR has double the data in 2006 (0.5 ab−1)

We hope to quadruple the data by 2008 (1 ab−1)

January 30, 2007

Oxford, Mississippi



Romulus Godang


Search for Higgs Particle

How the elementary particles get their mass ?

� Higgs mechanism (Peter Higgs, 1964) play a central role in the unification

of electromagnetic and weak interaction by providing W± and Z0 bosons

� It implies the existence of a single neutral scalar particle so called

“Higgs particle” yet Leon Lederman called it “God particle”

� The challenge: Higgs mass is a free parameter in the SM

↪→ what is the Higgs mass range ?

� The first search of Higgs was done by LEP, CERN (2003)

↪→ yield a lower limit: MH > 114.4 GeV (C.L. only)

� Can Fermilab (D0 and/or CDF) discover the Higgs particle

before the more powerful collider, LHC turn on (2007) ?

(U. Miss at D0: B. Quinn and A. Melnitchouk)

January 30, 2007

Oxford, Mississippi



Romulus Godang


Search for Higgs Boson Status

� January 8, 2007: CDF measured the mass of W :

MW = 80, 413± 48 MeV

↪→ the new average MW = 80, 398± 25 MeV

→ upper limit of MH down from 166 GeV to 153 GeV

� Tevatron is only capable of finding Higgs if MH ≤ 170 GeV

→ Fermilab has a good change to find Higgs!

Higgs mass (GeV)100 120 140 160 180 200

) (p

b)

(*)

WW

→B

R(H

×σ

-110

1

10

210

Exc

lud

ed a

t L

EP

Standard Model

4th Generation Model

ν lνl→(*)WW→H

95% CL LimitExpectedObserved

-1DØ, 320 pb

Higgs mass (GeV)100 120 140 160 180 200

) (p

b)

(*)

WW

→B

R(H

×σ

-110

1

10

210

110 120 130 140 150 160 170 180 190 200

-110

1

10

210

)2Higgs Mass (GeV/c110 120 130 140 150 160 170 180 190 200

) (p

b)

*W

W→

x B

R(H

Hσ95

% C

.L.

-110

1

10

210

Standard Model

4th Generation Model

Expected Limit

95% C.L. Limit

Exc

lud

ed L

EP

January 30, 2007

Oxford, Mississippi



Romulus Godang


Search Higgs at Muon Collider

� Unique features of a Muon Collider (µ+ − µ−):

• Bremsstrahlung radiation effect is negligible (scales by m−4µ )

so it does not limit their circular acceleration to reach multi-TeV energies

• Direct s-channel coupling (Mandelstam) to Higgs boson resonances is

40,000 (mµ/me)2 > in (µ+µ− → h) than in (e+e− → h)

=⇒ R(µ+µ−)higgs � R

(e+e−)higgs

h

b

b

µ+

µ−

( t )

(t )

~mµ ~mb (mt)

• U. Miss at Muon Collider : D. Summers, L. Cremaldi, R. Godang, S. Bracker

January 30, 2007

Oxford, Mississippi



Romulus Godang


Heavy Neutral Higgs Bosons

� In MSSM, the heavy Higgs bosons are largely degenerate

� The Higgs boson cross section in s-channel:

σh(√s) = 4πΓ(h→µµ)Γ(h→X)

(s−m2h)2 + m2

h(Γhtot)2 =⇒ σ√s = (2 MeV )

(R

0.003%

) ( √s

100 GeV

)

� The resonances are clearly overlapping (separated by ∼ 1 GeV )

� Muon Collider could separate out these states with energy resolution:

R = 0.01% and R = 0.06%

January 30, 2007

Oxford, Mississippi



Romulus Godang


LHC Detectors

� LHC: p− p collisions with CM-energy√s = 14 TeV

� CMS Collaboration: 2000 scientists with 155 institutes in 37 countries

↪→ Search for Higgs is one of the main goals in CMS

↪→ Search for Black Holes: M. Cavaglia, R. Godang, L Cremaldi, D. Summers

January 30, 2007

Oxford, Mississippi



Romulus Godang


The CMS Experiment

U. Miss: L. Cremaldi, R. Godang, R. Kroeger, D. Sanders, D. Summers

January 30, 2007

Oxford, Mississippi



Romulus Godang


CATFISH: New MC Generator

� We introduce a new MC generator so called CATFISH

CATFISH (Collider grAviTational FIeld Simulator for black Holes)

� New features of CATFISH compared to other BH generators :

• CATFISH is more flexible and user friendly

• It includes different final BH decay modes with

possibility of remnant formation

• It includes Graviton field emissivities

� CATFISH authors: M. Cavaglia, R. Godang, L. Cremaldi, D. Summers

� The paper has been submitted for a publication

January 30, 2007

Oxford, Mississippi



Romulus Godang


CATFISH Website

� CATFISH is well documented and available for public

http://www.phy.olemiss.edu/GR/catfish/

January 30, 2007

Oxford, Mississippi



Romulus Godang


BH Events Shape in CATFISH

� BH events are expected to be highly spherical due to

the spherical nature of Hawking evaporation process

0.00 0.25 0.50 0.75 1.00

Sphericity

10-1

1

101

102

103

104

Num

ber

of E

vent

s

M★ = 1 TeV, n = 6

Mmin = 1 TeV

np = 2, BD

np = 4, BD

np = 2, YR

np = 4, YR

0.00 0.25 0.50 0.75 1.00

R2 ≡ H2/H0

10-1

1

101

102

103

104

105

Num

ber

of E

vent

s

M★ = 1 TeV, n = 6

Mmin = 1 TeV

np = 2, BD

np = 4, BD

np = 2, YRnp = 4, YR

� Experimentally one needs to distinguish between BH events shape

with qq events as BH-background (back-to-back events shape)

• (left) Sphericity BH events shape, → S > 0.30 (depends on Mmin)

• (right) Fox-Wolfram moment, → R2 < 0.50

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Higgs Production at CMS

g

g g fusion :

g

g

g

t t fusion :

t Ho

Ho

t

t

t

t

t

t

q

q

WW, ZZ fusion :

q

q

q

q

Ho

Ho

W, Z bremsstrahlungq

Ho production at hadron colliders:

W,Z

W,Z

W,Z

W,Z

But : BR ( H Z¡Z¡ 4l–) = 1.4 ¥ 10—3

BR ( H Z¡Z¡ 4µ–) = 3 ¥ 10—4

gg H

qq Hqq

gg,qq Hbb

gg,qq Htt

qq HZ

qq’ HW

107

106

105

104

103

102

10-1

10-2

10-3

10-4

10

1

0 200 400 600 800 1000

MH (GeV)

σ (p

b)

σ(pp H+X)

s = 14 TeV

mt = 175 GeV

CTEQ4M

D_D

_118

6 .c

NLO QCD

M. Spira et al.

even

ts fo

r 10

5 pb

-1January 30, 2007

Oxford, Mississippi



Romulus Godang


The Higgs Discovery at CMS

� The relative light Higgs mass MH < 120 GeV

� For MH < 150 GeV , the most promising channel:

H0 → γγ (dominated by energy resolution)

� But the branching fraction is small

� The decay width is about few tens keV only

ECAL performance is very crucial in this analysis

� We are working on ECAL and HCAL simulation

(GFLASH): R. Kroeger and R. Godang

1

1

50 100 200 500 1000

50 100 200 500 1000

10—1

10—1

10—2

10—3

10—2

102

10

10—3

MH [GeV]

MH [GeV]

Γ(H

) [G

eV

]B

R(H

)

WW

ZZ

Zγγγ

τ+τ—

gg tt

cc

SM HiggsBranching ratios and total decay width

D_D

_ 20

61 c

bb

January 30, 2007

Oxford, Mississippi



Romulus Godang


The Higgs Discovery at CMS...

� 3 channels cover Higgs mass range

• H0 → γγ

• H0 → Z0Z0

• H0 →W±W∓

� We expected to have about

10 fb−1 data for 1 year running

� We hope to discover

Standard Model Higgs in 2008 ?

� U. Miss proposed to measure

H0 →W+W−, (W+W− → `+`−νν)

� More data are needed to study the Higgs’ properties

102

10

1

10—1

100 200 300 400 500 600

MHiggs [GeV]

H → γγH → ZZ

H → WW

LHC 14 TeV (SM NLO Cross Sections)

Dis

cove

ry L

um

ino

sity

[fb

—1]

D_

D_

12

85

c

5σ Higgs Signals (statistical errors only)

January 30, 2007

Oxford, Mississippi



Romulus Godang


Summary

� CP Violation in B system has been observed

α = (92.1± 5.1)◦ β = (24.6± 1.7)◦ γ = (63.1± 5.0)◦

� Current precision of |Vub| and |Vcb| measurements :

• (∆|Vub||Vub| ) = (3.3exp ± 2.9model ± 4.7SF ± 4.0th)% = 7.6%

• BABAR is aiming to measure (∆|Vub||Vub| ) = 5%

• (∆|Vcb||Vcb| ) = 2%. (Partial Reconstruction method will confirm this)

• Many interesting physics analyses are available at BABAR

� Search for Higgs and BH at LHC is underway

� Using CATFISH, we hope to discover mini BH production at CMS

� New discoveries are waiting to be explored at LHC !

January 30, 2007

Oxford, Mississippi



Romulus Godang


Hopefully...

� Will the Higgs be discovered in 2008 ?

T H A N K S !

January 30, 2007

Oxford, Mississippi



Romulus Godang


understanding the matter-antimatter asymmetry of the ...what do we know about matter and antimatter...

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