# Presentation: 588443

## Searches for Supersymmetry         at the Tevatron

- Marie-Claude Cousinou
- CPPM-Marseille  Université de la Méditerranée
- For the D0 and CDF collaborations

*Introduction*
*Searches for **Charginos **and **Neutralinos** **(RPC)*
*Searches for **Charginos**, **Neutralinos** or **Sleptons **(RPV)*
*Searches for **Squarks** and **Gluinos** (**RPC)*
*Searches for **Squarks **(RPV)*
*Searches for** **B****s****** ********+** **********-***
*Conclusion*

## Tevatron  at Fermilab – Run II

**   ****(1.8 TeV ******** 1.96 TeV)  => **
**  ****Higher cross sections**** **
** ****Higher antiproton intensity**
**  ****6********6 ******** 36 ******** 36 bunches(3.5 ********s ******** 396 ns)**
**  ****antiproton “recycler” => ****Higher luminosity**
** ****RunII goal:  ********9 fb-1 in 2009**

**Chicago**
**     ******

**Tevatron**

**Main Injector**
** ****& Recycler**

**DØ**

**CDF**

******p source**

**>1 fb****-1**

## D0                   CDF   

- Both general purpose detectors well understood  and highly efficient with:
-         Excellent calorimeters and muon chambers coverage
-         Precision tracking (Silicon Vertex Detector)
- Analyses presented here use up to 390 pb-1

## Some SUSY parameters    :  reminder

- R=(-1)3B+2L+S = +1 (SM) ; = -1 (SUSY)
**LSP**** is stable if  R parity is conserved  (****RPC)**
**Small violation of R parity  is not excluded (****RPV****)=> additional couplings and ****LSP**
**decays in SM particles**
- SUSY breaking Mechanisms           2 models treated here:
- Graviton mediated  model (mSUGRA)                 Gauge mediated model ( GMSB )                                                                                                                                                                                                                                                       **(new chiral supermultiplets: messengers)**
**    ****mo common scalar mass                                               ******** SUSY breaking scale**
**    ****m****1/2**** common gaugino mass                                         M****m ****messenger mass (2 ********)**
**    ****tan ******** ratio of Higgs Vacuum expectation Values      N****5****  number of messengers  **
**    ****sign(********)  sign of Higgsino mass term                            tan ******** and sign(********) **
**    ****A****0**** trilinear coupling                                                     C****grav ****= factor multiplying effective mass of  ******** **                                                                                         **gravitino**
-    LSP =                                                                         LSP =             NLSP =

**Some SUSY parameters    :  reminder**

## Charginos and Neutralinos in 3 leptons + Etmiss

- Final state : 3 * leptons* + large Etmiss
- Clean signature but small event rates (xBr<0.5pb)
- and leptons with low PT

-     **ee**** or ******** ******** or ****e ********  ****(P****T**** cuts ********10 GeV)**
**or ****e** ******  ****or**** ******** ******** **** ****(had.decay of the ******** :NN) **+ ***lepton***
**(isolated high quality track with P****T**** cut ******** 5 GeV)**
- or **2 ******** like sign (P****T**** cuts ********10GeV)**
- +  **E****T****miss**** > 22GeV**
- +**   anti Z cuts**

-                6 analyses

## eel

- eel

- l

- l

- Search for Charginos and Neutralinos in 3 ***leptons*** + ETmiss

| Channel | Observed | SM expected |
| --- | --- | --- |
| e e + l | 0 | 0.210.12 |
| e  + l | 0 | 0.310.13 |
|   + l | 2 | 1.750.57 |
| Same sign    | 1 | 0.660.37 |
| Sum | 3 | 2.930.5457 |
| e  + l | 0 | 0.580.14 |
|   + l | 1 | 0.360.13 |

## mSUGRA  Search for Charginos and Neutralinos

**** x Br(3***l***) is mainly a function of
-                and

- 3l-max**:**  low m0 -  leptonic BR is
- maximally enhanced for
- heavy-Squarks**:****                             **
-                      cross** **section is maximal
- large m0**:** **        **large** **
**W/Z exchange graph is dominant            small leptonic BR**

-                hep-ex/0504032      analyses eel, l, el,

- Including the el and l analyses gives better sensitivity:
- limit improves by 10% for tan=3
- more expected at large tan, where the ’s dominate the final state

## Charginos and Neutralinos in 3 leptons + Etmiss

**2 analyses: ee + *****l***

|  | PT(e1,e2) GeV | PT(l3) GeV | ETmiss GeV | Lumi pb-1 | SM exp. | Obs. |
| --- | --- | --- | --- | --- | --- | --- |
| High PT | > (20,8) | e or   > (4) | >15 | 346 | 0.160.07 | 0 |
| Low PT | > (10,5) | track   > (4) | >15 | 224 | 0.360.27 | 2 |

**m****0*** =100 GeV, ***m****1/2*** =180GeV, tan(****)=5, ****>0             0.5 events*

*High P**T*

********* ******channel will be include soon***

*Low P**T*

## GMSB  Chargino and Neutralino in  + ETmiss (263 pb-1) –       (202 pb-1) Combination : hep-ex/0504004

|  | Obs | Exp. SM | M() (GeV) |
| --- | --- | --- | --- |
| D0 | 2 | 3.70.6 | >195 |
| CDF | 0 | 0.30.1 | >167 |

- M(********)>209 GeV/c2
- M(******0**)>114 GeV/c2

-    D0/CDF  Selection:
- 2 photons
-  ET(****)> 20 **/ **13 GeV
-  ETmiss > 40 **/ **45 GeV

***M******m******=2************, N******5******=1, tan************=15,************ >0***

## (1-speed)/speed

- appear as slow moving high PT  ******  **
**        **PT>15 GeV + isolation
- timing of the muon scintillators used
-          Speed significantly slower than c
-   0 candidate     expected: 0.660.6event
-                             no SM background

- Production of a pair of **CMSP** (“stable”   or ********)

- (1-speed)**/**speed

- Limits:
- GMSB:  CMSP is
-                                     not sensitive yet
- AMSB:  CMSP is             (                        )
- Higgsino-like:
- Gaugino-like:

-       **gaugino-like**

- limit=0.06-0.62 pb

## RPV decay of LSP (    )
ijk coupling      Lifetime of LSP

Resonant sparticle production
’ijk coupling 

*E**j **(D**j **,U**j**) **are the electron (down and up quark) SU(2)**L** singlet superfield*
*     **** ******,****    ** ,**        are Yukawa couplings*

**RPV **decay **of LSP (    )**
******ijk**** ****coupling      ****Lifetime of LSP**
**Resonant sparticle production**
******’****ijk**** ****coupling**** **

- R-parity violation : RPV

*RPV **consequences on*
*experimental signatures ****:***

-  SUSY signature can be very different
-  Less missing ET
-  More leptons and jets
-  Sparticle may be produced by RPV couplings as single Sparticle

*Additional terms in the superpotential:*

## RPV       ijkLiLjEk coupling 

- _The couplings considered :_
******121**  eeee,   eee  or ee + 
******122**  , e or ee + 
******133**  , e or ee + 

- RPV       ******ijk****L****i****L****j****E****k** coupling

-      Selection:
-      3 isolated leptons +  low PT cut on 3rd lepton + loose ETmiss cuts

******133**

|  | Lumi. Int.    (pb-1) | Data | SM exp. | parameters | 
(GeV) |
| --- | --- | --- | --- | --- | --- |
| eel (l=e, ) | 238 | 0 | 0.50.4 | m0=250 GeV,tan=5,A0=0, >0 | 181 |
| l (l=e, ) | 160 | 2 | 0.61.9 | m0=250 GeV,tan=5,A0=0, >0 | 165 |
| eehad | 200 | 0 | 1.0 1.4 | m0=80 GeV,tan=10,A0=0, >0 | 118 |

## ,

- RPV  ******211****L****2****Q****1****D****1**  coupling

-  2 jets and 2 isolated 
-    and PT (jet,)~20 GeV
-   efficiency ~ 0.5-0.6%

**2 (data) / 1.1 ******** 0.4 SM**

***,***

*the invariant masses of the**        **and **     *
*can be reconstructed**   *

***A0=0, tan************=2, sgn(************)=-1***

## RPV       Search for Scalar Neutrino  (1)

- RPV       Search for Scalar Neutrino  (1)

***M(e************)          TeV***

*e** **(E**T**>20 GeV)** + **** **(P**T**>20 GeV)** + **opposite charged*
*Acceptance ~ 25%** (M(e ****)= 350 GeV)*
*Mass resolution ~15 GeV** for M(e ****)=300 GeV*
*Data: 77 events  -   SM exp.: 71.3****1.8(stat)*
*with  **M(e ****)>100 GeV**    :*
*      **Data:5 events** - **SM exp.:8.0****1.1(stat)*

***M(e************)          TeV***

*** ** **BR*

*********132****=0.05*
*******’****311****=0.16*

## RPV Search for Scalar Neutrino (2)

- RPV Search for Scalar Neutrino (2)

| Channel | Cuts (GeV) | Obs. | SM exp. |           (GeV) |
| --- | --- | --- | --- | --- |
| ee | ET(e)>25 + M(ee)>500 | 0 | 0.5  0.1 | 725  |
|  | PT()>20 + M()>500 | 1 | 1.2  0.1 |  |
| h
 | PT(h)>25 + ETmiss>15
        +Mvis>120 | 4 | 2.8  0.5 | 377  |

**Limit at  95%CL**
**If ********’****2*****Br = 0.01**

- {

- ee

****

*q*

*q*

***l ******-***

##   Squarks and Gluinos      

-   Squarks and Gluinos

- low m0

- high m0

- intermediate m0

|         mo
    310 pb-1 | # jets (PT GeV) | HT=|Ptjet|
  (GeV) | ETmiss
(GeV) | Exp. SM  | Obs. |
| --- | --- | --- | --- | --- | --- |
| Low values | 2 jets (60,50) | >250 | >175 | 12.85.4 | 12 |
| Int. values | 3 jets (60,40,25) | >325 | >100 | 6.13.1 | 5 |
| High values | 4 jets (60,40,30,25) | >250 | >75 | 7.10.9 | 10 |

|  254 pb-1 | 3 jets (125,75,25) | >350 | >165 | 4.21.1 | 3 |
| --- | --- | --- | --- | --- | --- |

## mSUGRA   Squarks – Gluinos in jets + ETmiss

- mSUGRA   Squarks – Gluinos in jets + ETmiss

*Enormous QCD background !*
*Missing E**T** mis-measurements:*
***Jet energy mis-measured***
***Beam halos-hot towers******...***
*    **after E****T******miss**** cleaning cuts:*

*No charged leptons + E****T******miss**** **non aligned with jets*
*Data:   3   **SM exp. ** *4.21.1* **events*
*Expect ~ 0.7 - 4.8 events for M(q,g)~380 GeV*

## mSUGRA   Squarks – Gluinos in jets + ETmiss   

- m(squark)  318 GeV
- (m0= 25 GeV)
- m(gluino)  233 GeV
- (m0= 500 GeV)
- m(gl)=m(sq) > 333 GeV

**QCD**

- mSUGRA   Squarks – Gluinos in jets + ETmiss

- 4 jets analysis

- (m0,m1/2)=(500,80) GeV

## Search for Gluino decaying in Sbottom Bottom

- 95% C.L

|  | Obs.  | Exp. SM |
| --- | --- | --- |
| Excl. Single b tag | 21 | 16.4  3.7 |
| Incl. double b tag | 4 | 2.6  0.7 |

**At least 3 jets E****T****>15 GeV + E****T****miss**** > 80 GeV**
**+ ****angular cuts between jets and E****T****miss**

## Direct Production of       decaying in 

- Direct Production of       decaying in

*Selection:*
*2 jets acoplanars (+3**rd** jet) + E**T**miss** cut +*
*single b-tag + lepton veto*

| M(    ) | Low val. | Med.val. | High val. |
| --- | --- | --- | --- |
| ET(j1,j2) (GeV) | >(40,15) | >(40,15) | >(70,40) |
| ETmiss
(GeV) | >60 | >80 | >100 |
| Data | 36 | 15 | 2 |
| SM exp. | 38.62.8 | 19.61.7
 | 4.40.4 |

## RPC      Search for pair production of Stop

- RPC      Search for pair production of Stop

- 2 jets ET  35,25 GeV + ETmiss  55 GeV
- + e.g anti QCD back to back jets
- + no isolated lepton pTe,  10 GeV, anti 
- + double heavy-flavor-tagging

*If **     **is the lightest** *

- Limit from   CDF RunI (88pb-1) :
-                              for
- Due to:
- Higher ETmiss trigger threshold
- and larger systematic uncertainties:
- Jet Energy Scale correction (6%-33%)
-  Tagging heavy flavor jets (13%)

**11 (data) / 8.3 ******** 2.0 SM**

## RPV       Search for Stop decaying in b +      

|  | e |  | all |
| --- | --- | --- | --- |
| Exp. SM | 2.60.6 | 2.20.5 | 4.80.7 |
| observed | 2 | 3 | 5 |

- RPV       Search for Stop decaying in b + ******     **

******’****333**

- Search for                                              BR(                  )  100%

- Selection: **1*****l*** (***l***=e, ****** ****P****T****>10GeV****) + ****1********had********(****P****T****>15GeV****)**

**+  ******** 2 jets   +     M****T****(*****l,E******T******miss******) < 35 GeV  ( to remove W)***

## Bs  +-

- Select +-    (PT> 2-3GeV) from displaced vertices
- Count events inside a M() mass window (100MeV around the BS mass)
-          0 event
- Normalize the upper limit to the number of
- B               J/ K  events

- Bs  +-

- In SM, small BR ~ 3.5 109
- but in SUSY, enhancement ~ (tan)6 factor

| at 90%C.L | Lum. (pb-1) | BR(Bs  +-) |
| --- | --- | --- |
|  | 364 | < 1.5 10-7 |
|  | 300 |       < 3.0 10-7 |

*.*

## Conclusions

*CDF** and **D0** have both covered many SUSY particles searches using an integrated luminosity of about 350pb**-1*
*Substantial improvement wrt Run I*
*Limits above LEP’s in certain parameters space    *
*We are now analysing the **1 fb**-1** data, hoping for a discovery ,*
*otherwise there will be substantial improvement of the limits (see the Tevatron Connection Workshop talks (June 24-25))*