LHC Praha 2003 Detection of MSSM Higgs bosons

LHC Praha 2003 Detection of MSSM Higgs bosons using supersymmetric decay modes at CMS Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Topics • Introduction • neutral Higgs to SUSY (hep-ph/0112046) • charged Higgs to SUSY (hep-ph/0304093) • SUSY to Higgs (hep-ph/0304095) • Conclusion & outlook Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

MSSM Higgs sector • MSSM contains 2 Higgs doublets, therefore 5 physical Higgs states: h 0, H 0, A 0, H ~ degenerate in mass for high m. A looks like HSM (but mh < 130 Ge. V) • masses & couplings depend at tree level only on 2 parameters, say m. A & tan : (1< tan <60) • radiative corrections can be important (e. g. for h 0 !!) Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

MSSM Higgs masses Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Couplings Higgs couplings to fermions: _ • • • f H f • proportional to mass 3 rd generation favoured • tan enhances couplings to down-type fermions Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

SM channels … so main production mechanism for A 0 and H 0: and use decay mode: Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Discovery search COVERED • discovery of the heavy MSSM Higgses limited to upper triangle in m. A – tan plot • note: the h 0 can always be found • problem is that production mechanism (e. g. bb. A 0, H 0) needs tan enhancement Need new ideas to cover low tan - high m. A region … Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

New channels? Split problem up in two pieces: production and decay Let’s first assume ‘classical’ production mechanism: and lets look at the decays … Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Couplings revisited Higgs couplings to bosons? ? H V H H V V • • • for m. A > 200 Ge. V, cos( -a) ≈ 0. 01 Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Light sparticles … interesting coupling: ~0 A H 0 ~0 Z = 0 (neutralinos) = 0 doesn’t work for SM, but remember SUSY … SM + SUSY Physics @ LHC, Prague, July 2003 only SUSY Filip Moortgat, University of Antwerpen

Neutralino decays Leptonic decays would be preferred experimentally … BR goes down with tan Physics @ LHC, Prague, July 2003 BR goes down with slepton mass Filip Moortgat, University of Antwerpen

Sparticle modes The signature looks like: 4 isolated leptons (e, m) + ETmiss powerful signature against the SM + SUSY backrounds @ LHC fb intermediate sleptons Physics @ LHC, Prague, July 2003 s x BR Filip Moortgat, University of Antwerpen

Selection criteria Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Some distributions kept Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

A case study Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Table for case 1 Number of events after successive cuts (100 fb-1) Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Case 2 Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Discovery reach Typical discovery reach: A/H 4 leptons seems to prefer low tan , complementary to A/H !! Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Charged Higgs to sparticles Analogue production mechanism for H : + Analogue decay mode: H 2, 30 1, 2 3 l + ETmiss only 3 leptons, need to reconstruct additional top (t bjj) Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

More tricky this time works only for small region in MSSM parameter space … LEP excluded in red area we can do it!! M. Bisset (Uni. Bejing), F. Moortgat (Uni. Antwerpen), S. Moretti (Uni. Southampton) Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Charged Higgs selection Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Event selection Many backgrounds considered: Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Discovery Reach MSSM parameters: M 2 = 210 Ge. V, m = 135 Ge. V, Msleptons = 110 Ge. V, Msquark, gluino = 1 Te. V Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Second branch So we tried new decay modes … what about new production mechanisms? A 0 h 0 try to exploit MSSM Higgs bosons production in SUSY particle cascades H± H 0 A. Datta (Uni. Florida), A. Djouadi (Uni. Montpellier), M. Guchait (TIFR Mumbay), F. Moortgat (Uni. Antwerpen), Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Scenarios Scenario 1 (big cascades) q~ Scenario 2 (little + big cascades) q~ (720 Ge. V) (1080 Ge. V) g~ (900 Ge. V) g~ (600 Ge. V) ~ ~ ~ (340 Ge. V) ~ h 0, H 0, A 0, H± ~ ~ ~ (480 Ge. V) h 0, H 0, A 0, H± ~ ~ (270 Ge. V) (170 Ge. V) (95 Ge. V) Physics @ LHC, Prague, July 2003 h 0 ~ (145 Ge. V) Filip Moortgat, University of Antwerpen

Scenarios (cont’d) Scenario 3 (big cascades) g~ (1200 Ge. V) q~ (800 Ge. V) ~ h 0, ~ ~ ~ (375 Ge. V) H 0 , A 0 , ~ ~ H± (150 Ge. V) (110 Ge. V) Physics @ LHC, Prague, July 2003 Scenario 4 (little cascades) g~ (1200 Ge. V) ~ ~ (1000 Ge. V) ~ q~ ~ (800 Ge. V) ~ (400 Ge. V) h 0, H 0, A 0, H± ~ (200 Ge. V) Filip Moortgat, University of Antwerpen

Cross section x BR’s Scenario 1 Scenario 2 Scenario 3 Scenario 4 m. A =150 Ge. V tan = 5 Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Selection strategy • look for main decay modes of neutral and charged Higgses: • h 0, A 0, H 0 bb • H± (cause m. H±= 170 Ge. V) • first thing to do: make sure triggering is guaranteed, then separate SUSY cascades from SM background • let’s look at some kinematical distributions … • using ISASUSY 7. 58 + HERWIG 6. 4 + CMSJET 4. 801 + HDECAY + TAUOLA + ISAWIG Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Kinematics Jet multiplicity in SUSY cascade signal vs. SM tt- background Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Kinematics (2) ET (hardest jet) in SUSY cascade signal vs. SM tt- background Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Kinematics (3) Missing ET in SUSY cascade signal vs. SM tt- background Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Kinematics (4) Total transverse energy in SUSY cascade signal vs. SM tt background: Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Selection criteria for neutral Higgses • we require the event to contain at least 5 jets • the hardest jet in the event should have ET > 300 Ge. V • the transverse missing energy ETmiss > 150 Ge. V • the effective mass > 1200 Ge. V • the event should contain at least two b-tagged jets, with 45 Ge. V < ET < 120 Ge. V. b-tagged means that both jets should contain at least two tracks with s(ip) = ipxy/Dipxy > 3. Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Results: scenario 1 30 fb-1 : susy signal : susy bkg : SM tt bkg Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Results: scenario 2 h 0 30 fb-1 : susy signal : susy bkg : SM tt bkg Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Results: scenario 3 h 0 30 fb-1 H 0 , A 0 : susy signal : susy bkg : SM tt bkg Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Results: scenario 4 h 0 30 fb-1 H 0 , A 0 : susy signal : susy bkg : SM tt bkg Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Selection criteria for charged Higgses • we require the event to contain at least 5 jets • the hardest jet in the event should have ET > 300 Ge. V • the transverse missing energy ETmiss > 200 Ge. V • the event should at least contain one hadronic -jet, i. e. a narrow jet with a hard charged track (one prong), isolated in calo and tracker, with ET > 80 Ge. V • more than 75% of the -jet transverse energy should be carried by the charged track (= polarization effect) Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Charged Higgs results H+ effect visible in Sc 4, but not so convincing since no invariant mass peak m. H+ =170 Ge. V tan = 5 Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

tan dependence tan = 10 tan = 30 Scenario 3 Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Discovery reach at 30 fb-1 region where H 0 and A 0 can be found in SUSY cascade decays h 0 can be found in full plane!! Physics @ LHC, Prague, July 2003 Scenario 3 Filip Moortgat, University of Antwerpen

Conclusions • we have studied supersymmetric decay channels of the MSSM Higgs bosons in CMS • for the heavy neutral Higgs bosons, we have found an interesting complementarity between the reach of the A, H 20 20 4 l + ETmiss and the SM channels • works also for charged Higgses, but only in small region of parameter space Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Conclusions (2) • we also explored a new mechanism that can abundantly produce neutral and charged Higgs bosons • we have shown a discovery potential for heavy MSSM Higgs bosons with this production mechanism, complementary to both the standard channels and the sparticle channels • we have shown a potential for the production of the light Higgs from heavy gauginos, which could complement the standard searches in the difficult 100 < mh < 130 Ge. V region. Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Outlook Higgs SUSY • look again at A, H i 0 j 0 and try to access high mass region (Bisset-Moortgat-Moretti) SUSY Higgs • look at A, H instead of A, H bb • look closer at scenario 1 and 2 (squarks heavier than gluinos) • look closer at H , especially interested in mass region around mtop where other channels don’t work • can we reconstruct cascade decay chains with Higgs bosons in the final state (bb instead of dileptons)? (Datta-Djouadi-Guchait-Moortgat) Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Backup slides Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Discovery reach at 100 fb-1 region where H 0 and A 0 can be found in SUSY cascade decays h 0 can be found in full plane!! Physics @ LHC, Prague, July 2003 region where only h 0 can be found Scenario 3 Filip Moortgat, University of Antwerpen

Results Let’s consider two cases: s x BR Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Dilepton edges Dilepton edge at M 2 -M 1 is clearly visisble Double dilepton edge!! Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Slepton mass effect Dependence of on higgsino and slepton masses: Other MSSM parameters: MA = 350 Ge. V, tan = 5, M 1 = 75 Ge. V, M 2 = 150 Ge. V, Msquark, gluino = 1 Te. V Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Why is low tan prefered? # events = A x B x C 2 A B C At higher tan : taus instead of electrons/muons … Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Charged Higgs search Dominant production: + We can exploit t(b)H associated production! reconstruct additional top (t bjj) Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Branching ratios Main channels: • H tb Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

H : polarization effect Strategy: • reconstruct hadronic top (t bjj) _ Main backgrounds: tt, Wtb, W + jets W and H± have different spin exploit polarization effects !! (D. P. Roy) harder pions from H± … Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen

Discovery reach all channels: • jet + jet • lepton + lepton Physics @ LHC, Prague, July 2003 Filip Moortgat, University of Antwerpen