| Literature DB >> 31258406 |
Federico Ambrogi1, Sabine Kraml2, Suchita Kulkarni1, Ursula Laa2,3, Andre Lessa4, Wolfgang Waltenberger1.
Abstract
We investigate to which extent the SUSY search results published by ATLAS and CMS in the context of simplified models actually cover the more realistic scenarios of a full model. Concretely, we work within the phenomenological MSSM (pMSSM) with 19 free parameters and compare the constraints obtained from SModelS v1.1.1 with those from the ATLAS pMSSM study in arXiv:1508.06608. We find that about 40-45% of the points excluded by ATLAS escape the currently available simplified model constraints. For these points we identify the most relevant topologies which are not tested by the current simplified model results. In particular, we find that topologies with asymmetric branches, including 3-jet signatures from gluino-squark associated production, could be important for improving the current constraining power of simplified models results. Furthermore, for a better coverage of light stops and sbottoms, constraints for decays via heavier neutralinos and charginos, which subsequently decay visibly to the lightest neutralino are also needed.Entities:
Year: 2018 PMID: 31258406 PMCID: PMC6560698 DOI: 10.1140/epjc/s10052-018-5660-0
Source DB: PubMed Journal: Eur Phys J C Part Fields ISSN: 1434-6044 Impact factor: 4.590
Analyses covered by the Fastlim [33] EMs converted to the SModelS format. For each analysis, Fastlim considers 24 topologies covering stop-, sbottom- and gluino-pair production with direct or cascade decays to a higgsino LSP, inspired by the idea of “natural SUSY”. As explained in the text, efficiencies with uncertainties are set to zero, so in practice we use 163 of the FastlimEMs
| Analysis | Ref. | ID |
|---|---|---|
| Incl. | ||
| 0-lepton + 2–6 jets + | [ | ATLAS-CONF-2013-047 |
| 0-lepton + 7–10 jets + | [ | ATLAS-CONF-2013-054 |
| 1-lepton + jets + | [ | ATLAS-CONF-2013-062 |
| 0/1-lepton + 3 | [ | ATLAS-CONF-2013-061 |
| Third gen. | ||
| 0-lepton stop | [ | ATLAS-CONF-2013-024 |
| 1-lepton stop | [ | ATLAS-CONF-2013-037 |
| 2-leptons stop | [ | ATLAS-CONF-2013-048 |
| 2 | [ | ATLAS-CONF-2013-053 |
| EW | ||
| | [ | ATLAS-CONF-2013-093 |
The 22 searches considered in the ATLAS pMSSM study [7] and their correspondences in the SModelS v1.1.1 database. A superscript with the ID means that in addition Fastlim EMs for a preliminary version of the analysis are included, see Table 2. The monojet results from [43] are not implemented in SModelS because our SMS assumptions do not apply to dark matter simplified models. The analyses [50, 53, 55] do not provide useable SMS interpretations. Finally, searches for new resonances, long-lived particles, and disappearing tracks [56–59] currently cannot be treated in the SModelS framework
| Analysis | Ref. | ID | SModelS database |
|---|---|---|---|
| Inclusive | |||
| 0-lepton + 2–6 jets + | [ | SUSY-2013-02 | 6 UL, 2 EM |
| 0-lepton + 7–10 jets + | [ | SUSY-2013-04 | 1 UL, 10 EM |
| 1-lepton + jets + | [ | SUSY-2013-20 | 1 UL from CONF-2013-089 [ |
| | [ | SUSY-2013-10 | n.i. |
| SS/3-leptons + jets + | [ | SUSY-2013-09 | 1 UL (+5 UL, CONF-2013-007 [ |
| 0/1-lepton + 3 | [ | SUSY-2013-18 | 2 UL, 2 EM |
| Monojet | [ | – | – (but monojet stop; see below) |
| Third generation | |||
| 0-lepton stop | [ | SUSY-2013-16 | 1 UL, 1 EM |
| 1-lepton stop | [ | SUSY-2013-15 | 1 UL, 1 EM |
| 2-leptons stop | [ | SUSY-2013-19 | 2 UL |
| Monojet stop | [ | SUSY-2013-21 | 4 EM |
| Stop with | [ | SUSY-2013-08 | 1 UL |
| 2 | [ | SUSY-2013-05 | 3 UL, 1 EM |
| | [ | SUSY-2014-07 | – |
| Electroweak | |||
| | [ | SUSY-2013-23 | 1 UL |
| 2-leptons | [ | SUSY-2013-11 | 4 UL, 4 EM |
| 2- | [ | SUSY-2013-14 | – |
| 3-leptons | [ | SUSY-2013-12 | 5 UL |
| 4-leptons | [ | SUSY-2013-13 | – |
| Disappearing Track | [ | SUSY-2013-01 | n.a. |
| Other | |||
| Long-lived particle | [ | – | n.a. |
| | [ | – | n.a. |
CMS 8 TeV results included in the SModelS v1.1.1 database and used in addition to the ATLAS results in Tables 1 and 2
| Analysis | Ref. | ID | SModelS database |
|---|---|---|---|
| Gluino, Squark | |||
| Jets + | [ | SUS-12-028 | 4 UL |
| 3(1 | [ | SUS-12-024 | 2 UL, 3 EM |
| Jet multiplicity + | [ | SUS-13-012 | 4 UL, 20 EM |
| | [ | SUS-13-019 | 8 UL |
| | [ | SUS-13-004 | 5 UL |
| 1 lepton + | [ | SUS-13-007 | 3 UL, 2 EM |
| 2 OS lept. + | [ | PAS-SUS-13-016 | 2 UL |
| 2 SS leptons + | [ | SUS-13-013 | 4 UL, 2 EM |
| | [ | SUS-14-010 | 2 UL |
| Third gen. | |||
| 0 lepton + | [ | PAS-SUS-13-015 | 2 EM |
| 0 lepton + | [ | PAS-SUS-13-023 | 4 UL |
| 1 lepton + | [ | SUS-13-011 | 4 UL, 2 EM |
| | [ | PAS-SUS-13-018 | 1 UL |
| Soft leptons, few jets + | [ | SUS-14-021 | 2 UL |
| EW | |||
| Multi-leptons + | [ | SUS-13-006 | 6 UL |
Summary of results, listing the number of ATLAS-excluded pMSSM points tested in this study, the number of points excluded by SModelS when using UL-type results only, and the number of points excluded when using the full 8 TeV database including EM-type results
| Bino-like LSP | Higgsino-like LSP | |
|---|---|---|
| Total number of points | 38575 | 45594 |
| Number of points excluded—UL results only | 16957 | 25024 |
| Number of points excluded—full database | 21151 | 28669 |
Fig. 1Number of points excluded by SModelS using only UL results (in yellow), adding official EM results (in green), adding ‘home-grown’ EMs (in blue) and finally adding also Fastlim EMs (in red). For reference the total number of ATLAS-excluded points is also shown (in gray). On the left for bino-like LSP and on the right for higgsino-like LSP
Fig. 2Coverage in the gluino vs. neutralino mass plane, for gluino masses up to 2 TeV, for bino-like LSP scenarios (left) and higgsino-like LSP scenarios (right). The color code indicates the fraction of points excluded by SModelS, the text gives the total number of points tested in each bin. For comparison, the 95% CL exclusion line for the simplified model from [35] is drawn in black
Fig. 3Maximum r value reported by SModelS for allowed points, for gluino masses up to 2 TeV, for bino-like LSP scenarios (left) and higgsino-like LSP scenarios (right). Points are sorted from low to high r-values, with the highest values of r shown on top
Fig. 4Relative cross section in unconstrained decays with asymmetric branches (left) and long cascade decays (right), for scenarios with a bino-like LSP. Here the total cross section refers to the full 8 TeV SUSY cross section. Only SModelS-allowed points with total cross section larger than 10 fb are considered
Fig. 5Same as Fig. 4 but for points with a higgsino-like LSP
Fig. 6Cross section for the jets + missing topology in the gluino vs. squark mass plane, for bino-like LSP (left) and higgsino-like LSP (right). Only SModelS-allowed points are considered
Fig. 7Most important missing topologies for SModelS-allowed points with light gluinos. The legend lists, from top to bottom, the missing topologies with highest cross sections ordered by their by frequency of occurrence (points in color). The relevant diagrams, SUSY processes and labeling in SModelS notation are given in Appendix A
Fig. 8Coverage in the stop vs. neutralino mass plane, for masses up to 800 GeV, for bino-like LSP scenarios (left) and higgsino-like LSP scenarios (right). The color code indicates the fraction of points excluded by SModelS as compared to ATLAS, while the text gives the total number of points tested in each bin. For comparison, the black lines are the 95% CL exclusion curves for the simplified model from [44] (0-lepton mode, full line) and [45] (1-lepton mode, dashed line)
Fig. 9Coverage in the sbottom vs. neutralino mass plane, for masses up to 800 GeV, for bino-like LSP scenarios (left) and higgsino-like LSP scenarios (right). The color code indicates the fraction of points excluded by SModelS as compared to ATLAS, while the text gives the total number of points tested in each bin. The black line is the 95% CL exclusion line for the simplified model from [49]
Fig. 10Branching ratios of stop (left) and sbottom (right) decays into heavier neutralino mass eigenstates for SModelS-allowed points, leading to signatures for which no SMS results are currently available ( GeV). Here, bino- and higgsino-like LSP scenarios are combined. Gray points have for the decays considered. The black lines are the 95% CL exclusion lines for the simplified model from [45] (left) and the simplified model from [49] (right). See text for details
Fig. 11Coverage in the chargino vs. neutralino mass plane, for masses up to 700 GeV. Here, bino-like and higgsino-like LSP scenarios have been combined to increase the number of points. The plot on the left considers all analyses, the plot on the right only EW analyses. The color code indicates the fraction of points excluded by SModelS as compared to ATLAS, while the text gives the total number of points tested in each bin. For comparison, the exclusion line from the 3-leptons analysis [54] is shown in red and from the combination paper [84] is drawn in black
Fig. 12Coverage in the plane of lightest slepton (first two generations) vs. LSP mass, for masses up to 700 GeV. Here, bino-like and higgsino-like LSP scenarios have been combined to increase the number of points. The plot on the left considers all analyses, the plot on the right only EW analyses. The color code indicates the fraction of points excluded by SModelS as compared to ATLAS, while the text gives the total number of points tested in each bin. The exclusion lines for (red) and (black) are also shown for comparison
Fig. 13Coverage of EW-inos and sleptons by EW analyses analogous to the right plots of Figs. 11 and 12 but considering points with (instead of ) as excluded
Contributions of specific signal topologies to the total exclusion for the pMSSM point no. 192342466. The second column shows the topology cross section (production cross section times branching ratios), while the third column shows the topology contribution to the signal yield for the 2jt signal region of Ref. [35]. The last column shows the r-values obtained using each topology individually. The last line shows the corresponding results including all possible gluino and squarks decays, resulting in a larger total cross section and r-value. See text for details
| Topology | Cross section | Contribution to 2 | |
|---|---|---|---|
| 250 fb | 21 | 0.37 | |
| 664 fb | 59 | 1.01 | |
| 136 fb | 4 | 0.08 | |
| Total | 1220 fb | 100 | 1.70 |