TISB 24.04.2001 TISB: Gruppo del Tau 1

“Pigiama” TISB24.04.2001 (o 25.04.2001)

CERN

Gruppo di lavoro sul :Status report

Gruppo di lavoro sul :Status report

• Giuseppe Bagliesi• Simone Gennai• Giacomo Sguazzoni

TISB 24.04.2001 TISB: Gruppo del Tau 2

Guardando un solo jet…Guardando un solo jet…

h

L1 Tau(calo)

L2 Tau(calo)

L3pxl Tau (iso)

L3tk Tau

1o jet

2o jet

Cat

ena

di tr

igge

r 1o

jet

Qui sta il nostro

contributo

Questa configurazione

+ L3tk = taglio in PT

Riduzione del fondo

non sufficiente!!!

TISB 24.04.2001 TISB: Gruppo del Tau 3

L3tk sul 1o jetL3tk sul 1o jet

MH=200GeV

MH=500GeV

Eff vs. Rej (wrt L3pxl) with the full Tk reconstruction:

is really hard to get good signal efficiency and good Bkg rej looking only at 1st jet.

0 < PT cut < 40 GeV

TISB 24.04.2001 TISB: Gruppo del Tau 4

Guardando due jet…Guardando due jet…

h

L1 Tau(calo)

L2 Tau(calo)

L3pxl Tau (iso)

1o jet

2o jet

Cat

ena

di tr

igge

r 1o

jet

Cat

ena

di tr

igge

r 2o

jet

Qui

sta

il n

ostr

o co

ntri

buto

L1 Tau(calo)

L3tk Tau

.OR.

TISB 24.04.2001 TISB: Gruppo del Tau 5

L3tk sul 2o jet: Tracking regionaleL3tk sul 2o jet: Tracking regionale

o=(0,0,0) Z

1st tau jet

PV in p=(0,0,z0)

2nd tau jet:

L1 2nd tau jet candidateReg Tk reconstructs tk in the 2nd jet cone with tk vertex @ (0,0,z0)

TISB 24.04.2001 TISB: Gruppo del Tau 6

Possible L3tk selections applied to 2nd jet: 1. Isolation criteria similar to L3pxl with full reco Tk (A) 2. Cut on the number of reconstructed Tk in the cone

(B)

– there are still some parameters to be optimised– Very low PT cut is applied at L3Tk (~ 1 GeV)

– Both algorithms have good signal efficiency and achieve the desired bkj rejection

L3tk sul 2o jet: selezione eventiL3tk sul 2o jet: selezione eventi

TISB 24.04.2001 TISB: Gruppo del Tau 7

Global eff and bkg Rate Global eff and bkg Rate

Signal Eff .

L1 & L2 L3pxl L3tk Global

mH=200 GeV 0,42 0,73 0.70 / 0.83 0.21 / 0.25

mH=500 GeV 0,53 0,74 0.73 / 0.81 0.28 / 0.31

50- 80 GeV 3 x 10-4 0,19 0.38 @ 90% C.L. 2.1 x 10-5

80- 120 GeV 0,01 0,21 0.06 / 0.17 1.6 x 10-4 / 5.4 x 10-4

120- 170 GeV 0,04 0,19 0.07 / 0.14 5.2 x 10-4 / 1.0 x 10-3

Rate after L1,L2,L3 7.6 / 10.4 Hz

PRELIMINARY !

Really near to our goal !

1. Isolation criteria of L3pxl with full reco Tk (A)

2. Cut on the number of reconstructed Tk in the cone (B)

Need more statistics !

TISB 24.04.2001 TISB: Gruppo del Tau 8

Concludiamo… Concludiamo…

We have analysed 2nd L1 tau jet in the event reconstructing tracks with regional Tk.

– 2 L3Tk selection criteria studied:

• Full Tk isolation of tracks inside the cone (A).

• Number of reconstructed tracks in jet cone (B) .

– We achieve to get a Rate of about 10 Hz after all Trigger Levels with a global signal eff 25%

– All cuts are not yet optimised Buona notte!!!