SUSYPublicResultsDetails

Details on Official Data SUSY Material (√s=7 TeV, 0.07, 0.3, 40pb-1)

title	summary	link	date	Type	plots/tables
Early supersymmetry searches in events with missing transverse energy and b-jets with the ATLAS detector	This note describes a first set of measurements of supersymmetry-sensitive variables in heavy-flavor enriched final state events with jets and missing transverse energy, from initial √s = 7 TeV proton-proton collisions at the LHC. Events may contain identified leptons (electron, muon) while separate analyses are carried out considering the no-lepton case and the case with additional leptons. The measurements are based on 305 nb−1 of data collected with the ATLAS detector. General good agreement is found between data and Standard Model expectations estimated with Monte Carlo simulations.	here	20th August 2010	CONF	plots
Early supersymmetry searches in channels with jets and missing transverse momentum with the ATLAS detector	This note describes a first set of measurements of supersymmetry-sensitive variables in the final states with jets, missing transverse momentum and no leptons from the s = 7 TeV proton-proton collisions at the LHC. The data were collected during the period March 2010 to July 2010 and correspond to a total integrated luminosity of 70nb−1. We find agreement between data and Monte Carlo simulations indicating that the Standard Model backgrounds to searches for new physics in these channels are under control.	here	21st Jul 2010	CONF	plots
Early SUSY searches in events with one or more isolated leptons, jets and missing transverse energy	This note describes a first set of measurements of supersymmetry-sensitive variables in the final states with jets, missing transverse momentum and leptons using the sqrt{s}=7TeV proton-proton collisions at the LHC. The data were collected during the period March~2010 to July~2010 and correspond to a total integrated luminosity of 70nb-1. We find good agreement between data and Monte Carlo simulations indicating that the standard model backgrounds to searches for new physics are under good control.	here	21st Jul 2010	CONF	plots
Background studies to searches for long-lived stopped particles decaying out-of-time with LHC collisions	R-hadrons are massive, meta-stable particles predicted in several Supersymmetry scenarios. This note describes a first search for gluino R-hadrons which have come to rest within the ATLAS detector volume, particularly the calorimeter, and decay at some later time, dictated by the lifetime of the particle. We search for jets produced from the 2- or 3- body decays of the gluinos stopped within the calorimeter. Candidate events are triggered in the empty bunch crossings in order to remove collision backgrounds. Simple selection criteria enable the discrimination of signal-like events from the most pernicious background-like events, which result from the largest background, cosmic muons.	here	21st Jul 2010	CONF	plots/tables

Details on Official MC SUSY material (2008-2010, √s=7,10,14 TeV, 0.2-10fb-1)

2009-2010 public notes

title	summary	link	date	plots/tables
Prospects for Supersymmetry discovery based on inclusive searches at a 7 TeV centre-of-mass energy with the ATLAS detector	This note presents an evaluation of the discovery potential of Supersymmetry for channels with jets, leptons and missing transverse energy with the ATLAS detector. The LHC running scenario at a centre-of-mass energy of 7 TeV, delivering an integrated luminosity of 05−2fb−1 for the 2010-2011 run, is investigated.	here	17 Jul 2010	plots
Expected performance of the ATLAS detector in GMSB models with tau final states	Gauge Mediated Supersymmetry Breaking (GMSB) models provide a possible mechanism to mediate supersymmetry to the visible sector. In these models the lightest supersymmetric particle is usually the gravitino, while the next-to-lightest supersymmetric particle (NLSP) is either a neutralino or a slepton. In the case of a stau NLSP, events with large missing transverse energy, highly energetic jets and up to four tau leptons are expected in pp-collisions at the LHC providing a powerful channel to probe the GMSB theory. In this note we study the expected performance of the ATLAS detector in GMSB scenarios with a stau NLSP for a LHC center-of-mass energy of sqrt(s) = 10 TeV . A cut-based selection is optimised using an example GMSB signal and a scan of the GMSB parameter space is performed to determine the discovery reach as a function of the integrated luminosity. In addition, the invariant mass distribution of two tau leptons is used to study the measurement of masses of supersymmetric particles with larger event samples.	here	13 Nov 2009	plots
Background Estimation for Inclusive SUSY Searches - The Tiles Method	We discuss a new data-driven estimation technique, denoted {em Tiles Method}, for Standard Model (SM) background in inclusive SUSY searches. The Tiles Method translates prior knowledge on the SM distributions of discriminating variables in a two or higher dimensional grid into an estimate of the abundances of SM and beyond-SM events.	here	14 May 2009	plots/tables
Discovery Potential for Supersymmetry with b-jet Final States with the ATLAS detector	This analysis describes the ATLAS discovery potential for supersymmetry in inclusive searches with b-jets in the final state, assuming a luminosity of 1 fb^{-1} and a center of mass energy of 14 TeV. The different sources of backgrounds and the expected uncertainties in their determination are considered.	here	03 Apr 2009	plots
Searching for Supersymmetry with two same-sign leptons, multi-jets plus missing transverse energy in ATLAS	An analysis of a search for R-parity conserving supersymmetry is performed in final states with two same-charge leptons, two jets and missing transverse energy using the ATLAS detector at the LHC. This note includes a data-driven method to estimate the number of Standard Model background events, and discusses the discovery potential in early data with an integrated luminosity of 200 pb^{-1} of data at a center of mass energy of 10 TeV.	here	13 Aug 2009	plots/tables
Prospects for SUSY and UED discovery based on inclusive searches at a 10 TeV centre-of-mass energy with the ATLAS detector	This note presents an evaluation of the discovery potential of Supersymmetry and Universal Extra Dimensions for channels with jets, leptons and missing transverse energy. The LHC running scenario at a centre-of-mass energy of 10 TeV, delivering an integrated luminosity of $200 {pb}^{-1}$ for the 2009-2010 run is investigated.	here	22 Jul 2009	plots/tables
Data-Driven Determimation of tbar Background to Supersymmetry Searches in ATLAS	The Standard Model process of ttbar production is one of the most important backgrounds to searches for Supersymmetry (SUSY) at the Large Hadron Collider at CERN. We describe a new method to estimate the contribution of semileptonic top events in SUSY searches with large missing transverse energy, multi-jets and veto against leptons with the first 200~pb$^{-1}$ data of the ATLAS experiment	here	14 Jul 2009	plots
Discovering heavy particles decaying into single boosted jets with substructure using the kT algorithm	This note demonstrates a recently proposed method for determining the mass of boosted particles from their decay products by exploiting the substructure of the resulting single collimated jet using the kT algorithm. We illustrate this method with a simple RPV SUSY model using the ATLAS detector at the LHC. We consider the hadronic decay of boosted neutralinos into single jets composed of three collimated subjets. We consider up to 1fb-1 of integrated luminosity with 10TeV simulated data.	here	19 May 2009	plots
Prospects for detecting long-lived supersymmetric particles with ATLAS	In certain supersymmetry breaking scenarios, characteristic signatures can be expected which would not necessarily be found in generic SUSY searches for events containing high-pT multi-jets and large missing transverse energy. In this document, it is presented the expected response of the ATLAS detector to signatures involving high-pT photons which may or may not appear to point back to the primary collision vertex and long-lived charged sleptons and R-hadrons. Such processes often have the advantage of small Standard Model backgrounds and their observation could provide unique constraints on the different SUSY breaking scenarios. Using these signatures, discovery potentials are estimated for either Gauge-Mediated Supersymmetry Breaking or Split-Supersymmetry scenarios. These studies have been performed using Monte Carlo samples of SUSY and background processes corresponding to integrated luminosity of about 1 fb−1, corresponding to the first year of LHC running.	here	09 Feb 2009
Finding heavy long-lived charged particles with the ATLAS detector	Long lived charged particles are predicted by many models of physics beyond the standard model (SM). At the LHC, the common signature is a heavy long-lived charged particle with velocity smaller than the speed of light. This paper presents methods we developed for identifying slow particles and measuring their mass using the ATLAS muon spectrometer. The efficacy of these methods is demonstrated using two different models.	here +EPJC Vol. 62 No. 2 (July 2009	15 Jan 2009
Multi-Lepton Supersymmetry Searches	We investigate the potential of the ATLAS detector to discover new physics events containing three leptons and missing transverse momentum. Such final states are predicted in a variety of extensions to the Standard Model.	here	28 Dec 2008
Measurements from Supersymmetric Events	We review the techniques used to reconstruct the decay of supersymmetric particles and measure their properties with ATLAS at the LHC, concentrating on strategies to be applied to a data set of integrated luminosity of 1 fb^-1 that can be expected after the first year of operation of the LHC. These techniques are illustrated using several benchmark points chosen in the mSUGRA parameter space, but they are applicable to a broader range of supersymmetric (and other similar) models.	here	28 Dec 2008	plots
Prospects for Supersymmetry Discovery Based on Inclusive Searches	This note describes searches for generic SUSY models with R-parity conservation in the ATLAS detector at the CERN Large Hadron Collider. SUSY particles would be produced in pairs and decay to the lightest SUSY particle, (chi^0_1) which escapes the detector, giving signatures involving jets, possible leptons, and ETMISS.	here	28 Dec 2008	plots
Estimation of QCD Backgrounds to Searches for Supersymmetry	This note deals with techniques for estimating QCD multijet backgrounds to inclusive jets + ETMISS + leptons searches for Supersymmetry. The note documents how the backgrounds may be estimated using a data set with an integrated luminosity of 1 fb^-1 or less.	here	28 Dec 2008	plots
Data-Driven Determinations of W, Z and Top Backgrounds to Supersymmetry	The Standard Model processes of W boson, Z boson and top quark production each in association with jets constitute major backgrounds to searches for Supersymmetry at the LHC. In this note, we estimate the contribution of these backgrounds for a basic SUSY selection, and discuss methods to derive them from the initial 1 fb^-1 of integrated luminosity at ATLAS.	here	28 Dec 2008	plots
Supersymmetry Signatures with High-pT Photons or Long-Lived Heavy Particles	In certain Supersymmetry breaking scenarios, characteristic signatures can be expected which would not necessarily be found in generic SUSY searches for events containing high pT multi-jets and large missing transverse energy. This paper describes the expected response of the ATLAS detector to four signatures: high-pT photons which may or may not appear to point back to the primary collision vertex and long-lived charged sleptons and R hadrons. Such processes often have the advantage of small Standard Model backgrounds and their observation could provide unique constraints on the different SUSY breaking scenarios. Using these signatures discovery potentials are estimated for either Gauge-Mediated Supersymmetry Breaking or Split-Supersymmetry scenarios. Using Monte Carlo samples of SUSY and background processes corresponding to integrated luminosity of about 1 fb^-1 we study all aspects of the analysis, including the expected trigger response and offline data reconstruction.	here	28 Dec 2008

2008 public note: Results from the CSC Book: CERN-OPEN-2008-020

The results of the "CSC" exercise are documented in CERN-OPEN-2008-020 (the "CSC book", titled "Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics"). The SUSY results are on pages 1513 to 1694. Figures can be found here. The plots from the CSC SUSY chapter.

Main Simulation points:

This are the points used by ATLAS.

mSUGRA points full simulation

A few points were selected for the Rome Workshop (2005) to be used as a baseline for full simulation studies. These points are in different regions of the mSUGRA parameter space and are named SU1, SU2, ... One of these points (SU3) is in the bulk region and was studied for the Athens Workhop (2002). The full simulation of events corresponding to this point is repeated with different software releases, making it a benchmark scenario for SUSY full simulation studies. Not all of the points will be repeated for the CSC notes. The cross sections are for 14 TeV.

For a summary of the points used for full simulation studies see the table below:

Point	m_0 (GeV)	m1/2 (GeV)	A0(GeV)	tan(β)	sgn(μ)	x-sec (pb)	DC1	Rome	CSC
Coannihilation (SU1)	70	350	0	10	+	7.43 (a)		Y	Y
Focus Point (SU2)	3550	300	0	10	+	4.86 (a)		Y	Y
Bulk (SU3)	100	300	-300	6	+	18.59 (a)	Y	Y	Y
Low Mass (SU4)	200	160	-400	10	+	262 (b)		Y
Scan (SU5.1)	130	600	0	10	+	0.44 (b)		Y
Scan (SU5.2)	250	600	0	10	+	0.40 (b)		Y
Scan (SU5.3)	500	600	0	10	+	0.31 (b)		Y
Funnel (SU6)	320	375	0	50	+			Y	Y
Coannihilation (SU8.1)	210	360	0	40	+	6.44 (a)			Y
Coannihilation (SU8.2)	215	360	0	40	+	6.40 (a)			Y
Coannihilation (SU8.3)	225	360	0	40	+	6.32 (a)			Y

Notes: (a) From the Herwig output of csc11 production (b) Rome cross-section information

GMSB samples:

These points were introduced and standardised as part of the CSC exercise.

Older publicly accessible ATLAS notes on SUSY

ATLAS Notes in CDS
ATLAS Scientific Notes in CDS

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Major updates:
-- PascalPRALAVORIO - 29-Nov-2010

Responsible: PascalPRALAVORIO
Last reviewed by: Never reviewed