Records |
Author |
Alimena, J. et al; Hirsch, M.; Mamuzic, J.; Mitsou, V.A.; Santra, A. |
Title |
Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of Physics G |
Abbreviated Journal |
J. Phys. G |
Volume |
47 |
Issue |
9 |
Pages |
090501 - 226pp |
Keywords |
beyond the Standard Model; long-lived particles; Large Hadron Collider; high-luminosity LHC; collider phenomenology; high-energy collider experiments |
Abstract |
Particles beyond the Standard Model (SM) can generically have lifetimes that are long compared to SM particles at the weak scale. When produced at experiments such as the Large Hadron Collider (LHC) at CERN, these long-lived particles (LLPs) can decay far from the interaction vertex of the primary proton-proton collision. Such LLP signatures are distinct from those of promptly decaying particles that are targeted by the majority of searches for new physics at the LHC, often requiring customized techniques to identify, for example, significantly displaced decay vertices, tracks with atypical properties, and short track segments. Given their non-standard nature, a comprehensive overview of LLP signatures at the LHC is beneficial to ensure that possible avenues of the discovery of new physics are not overlooked. Here we report on the joint work of a community of theorists and experimentalists with the ATLAS, CMS, and LHCb experiments-as well as those working on dedicated experiments such as MoEDAL, milliQan, MATHUSLA, CODEX-b, and FASER-to survey the current state of LLP searches at the LHC, and to chart a path for the development of LLP searches into the future, both in the upcoming Run 3 and at the high-luminosity LHC. The work is organized around the current and future potential capabilities of LHC experiments to generally discover new LLPs, and takes a signature-based approach to surveying classes of models that give rise to LLPs rather than emphasizing any particular theory motivation. We develop a set of simplified models; assess the coverage of current searches; document known, often unexpected backgrounds; explore the capabilities of proposed detector upgrades; provide recommendations for the presentation of search results; and look towards the newest frontiers, namely high-multiplicity 'dark showers', highlighting opportunities for expanding the LHC reach for these signals. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Alimena, Juliette; Hill, Christopher S.] Ohio State Univ, Dept Phys, 191 W Woodruff Ave, Columbus, OH 43210 USA, Email: juliette.alimena@cern.ch; |
Corporate Author |
|
Thesis |
|
Publisher |
Iop Publishing Ltd |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0954-3899 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000570614200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4535 |
Permanent link to this record |
|
|
|
Author |
ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Castillo, F.L.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Miñano, M.; Mitsou, V.A.; Moreno Llacer, M.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Ruiz-Martinez, A.; Salt, J.; Santra, A.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
Title |
Search for direct production of electroweakinos in final states with one lepton, missing transverse momentum and a Higgs boson decaying into two b-jets in pp collisions at root s=13 TeV with the ATLAS detector |
Type |
Journal Article |
Year |
2020 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
80 |
Issue |
8 |
Pages |
691 - 29pp |
Keywords |
|
Abstract |
The results of a search for electroweakino pair production pp -> (chi) over tilde (+/-)(1) (chi) over tilde (0)(2) in which the chargino ((chi) over tilde (+/-)(1)) decays into a W boson and the lightest neutralino ((chi) over tilde (0)(1)), while the heavier neutralino ((chi) over tilde (0)(2)) decays into the Standard Model 125 GeV Higgs boson and a second (chi) over tilde (0)(1) are presented. The signal selection requires a pair of b-tagged jets consistent with those from a Higgs boson decay, and either an electron or a muon from the W boson decay, together with missing transverse momentum from the corresponding neutrino and the stable neutralinos. The analysis is based on data corresponding to 139 fb(-1) of root s = 13 TeV pp collisions provided by the Large Hadron Collider and recorded by the ATLAS detector. No statistically significant evidence of an excess of events above the Standard Model expectation is found. Limits are set on the direct production of the electroweakinos in simplified models, assuming pure wino cross-sections. Masses of (chi) over tilde (+/-)(1) (chi) over tilde (0)(2) up to 740 GeV are excluded at 95% confidence level for a massless (chi) over tilde (0)(1). |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Alderweireldt, S.; Aleksa, M.; Armbruster, A. J.; Avolio, G.; Barisits, M. S.; Bielski, R.; Bortfeldt, J.; Boyd, J.; Buat, Q.; Butti, P.; Buttinger, W.; Calace, N.; Camarda, S.; Camincher, C.; Campana, S.; Garrido, M. D. M. Capeans; Carli, T.; Catinaccio, A.; Cattai, A.; Chelstowska, M. A.; Coimbra, A. E. C.; Cortes-Gonzalez, A.; Czodrowski, P.; Dao, V; Dell'Acqua, A.; Deviveiros, P. O.; Di Girolamo, A.; Dittus, F.; Dudarev, A.; Duhrssen, M.; Dyndal, M.; Eifert, T.; Ellis, N.; Elsing, M.; Errenst, M.; Farthouat, P.; Fassnacht, P.; Feng, E. J.; Francis, D.; Froidevaux, D.; Goossens, L.; Gorini, B.; Guenther, J.; Guindon, S.; Hagebock, S.; Hawkings, R. J.; Heinrich, L.; Helsens, C.; Correia, A. M. Henriques; Hervas, L.; Hoecker, A.; Huhtinen, M.; Iengo, P.; Jenni, P.; Jovicevic, J.; Klioutchnikova, T.; Kohler, N. M.; Krasznahorkay, A.; Kuehn, S.; Kuwertz, E. S.; Langenberg, R. J.; Lassnig, M.; Miotto, G. Lehmann; Lenzi, B.; Longo, L.; Tobon, C. A. Marin; Marzin, A.; Mcfayden, J. A.; Meehan, S.; Meng, L.; Berlingen, J. Montejo; Morley, A. K.; Mornacchi, G.; Moschovakos, P.; Nairz, A. M.; Nessi, M.; Nordberg, M.; Javurek, T.; Palestini, S.; Pandini, C. E.; Pauly, T.; Pernegger, H.; Petersen, B. A.; Pontecorvo, L.; Poveda, J.; Astigarraga, M. E. Pozo; Queitsch-Maitland, M.; Raymond, M.; Rembser, C.; Rizzi, C.; Roe, S.; Rummler, A.; Salzburger, A.; Samarati, J.; Pineda, A. Sanchez; Schaepe, S.; Schioppa, E. J.; Schlenker, S.; Schmieden, K.; Schovancova, J.; Sidiropoulou, O.; Sanchez, C. A. Solans; Spigo, G.; Stewart, G. A.; Stockton, M. C.; Ten Kate, H.; Unal, G.; Vallier, A.; Vandelli, W.; Schroeder, T. Vazquez; Venturi, N.; Vuillermet, R.; Wells, P. S.; Wengler, T.; Wenig, S.; Wilkens, H. G.; Young, C. J. S.; Zanzi, D.; Zwalinski, L.; ATLAS Collaboration] CERN, CH-1211 Geneva 23, Switzerland |
Corporate Author |
|
Thesis |
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000559326900004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4500 |
Permanent link to this record |
|
|
|
Author |
MoEDAL Collaboration (Acharya, B. et al); Musumeci,E.; Mitsou, V.A.; Papavassiliou, J.; Ruiz de Austri, R.; Santra, A.; Vento, V.; Vives, O. |
Title |
Search for highly-ionizing particles in pp collisions at the LHC's Run-1 using the prototype MoEDAL detector |
Type |
Journal Article |
Year |
2022 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
82 |
Issue |
8 |
Pages |
694 - 16pp |
Keywords |
|
Abstract |
A search for highly electrically charged objects (HECOs) and magnetic monopoles is presented using 2.2 fb(-1) of p – p collision data taken at a centre of mass energy (E-CM) of 8 TeV by the MoEDAL detector during LHC's Run-1. The data were collected using MoEDAL's prototype Nuclear Track Detectord array and the Trapping Detector array. The results are interpreted in terms of Drell-Yan pair production of stable HECO and monopole pairs with three spin hypotheses (0, 1/2 and 1). The search provides constraints on the direct production of magnetic monopoles carrying one to four Dirac magnetic charges and with mass limits ranging from 590 GeV/c(2) to 1 TeV/c(2). Additionally, mass limits are placed on HECOs with charge in the range 10e to 180e, where e is the charge of an electron, for masses between 30 GeV/c(2) and 1 TeV/c(2). |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Acharya, B.; Alexandre, J.; Ellis, J. R.; Fairbairn, M.; Mavromatos, N. E.; Sakellariadou, M.; Sarkar, S.] Kings Coll London, Phys Dept, Theoret Particle Phys & Cosmol Grp, London, England, Email: Laura.Patrizii@bo.infn.il; |
Corporate Author |
|
Thesis |
|
Publisher |
Springer |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000838674800001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5326 |
Permanent link to this record |
|
|
|
Author |
MoEDAL Collaboration (Acharya, B. et al); Bernabeu, J.; Mamuzic, J.; Mitsou, V.A.; Papavassiliou, J.; Ruiz de Austri, R.; Santra, A.; Vento, V.; Vives, O. |
Title |
First Search for Dyons with the Full MoEDAL Trapping Detector in 13 TeV pp Collisions |
Type |
Journal Article |
Year |
2021 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
Volume |
126 |
Issue |
7 |
Pages |
071801 - 7pp |
Keywords |
|
Abstract |
The MoEDAL trapping detector consists of approximately 800 kg of aluminum volumes. It was exposed during run 2 of the LHC program to 6.46 fb(-1) of 13 TeV proton-proton collisions at the LHCb interaction point. Evidence for dyons (particles with electric and magnetic charge) captured in the trapping detector was sought by passing the aluminum volumes comprising the detector through a superconducting quantum interference device (SQUID) magnetometer. The presence of a trapped dyon would be signaled by a persistent current induced in the SQUID magnetometer. On the basis of a Drell-Yan production model, we exclude dyons with a magnetic charge ranging up to five Dirac charges (5g(D)) and an electric charge up to 200 times the fundamental electric charge for mass limits in the range 870-3120 GeV and also monopoles with magnetic charge up to and including 5g(D) with mass limits in the range 870-2040 GeV. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Acharya, B.; Alexandre, J.; Ellis, J. R.; Fairbairn, M.; Mavromatos, N. E.; Sakellariadou, M.; Sarkar, S.] Kings Coll London, Phys Dept, Theoret Particle Phys & Cosmol Grp, London, England, Email: jpinfold@ualberta.ca |
Corporate Author |
|
Thesis |
|
Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000620021300009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4723 |
Permanent link to this record |
|
|
|
Author |
MoEDAL Collaboration (Acharya, B. et al); Mitsou, V.A.; Papavassiliou, J.; Ruiz de Austri, R.; Santra, A.; Vento, V.; Vives, O. |
Title |
Search for magnetic monopoles produced via the Schwinger mechanism |
Type |
Journal Article |
Year |
2022 |
Publication |
Nature |
Abbreviated Journal |
Nature |
Volume |
602 |
Issue |
7895 |
Pages |
63-67 |
Keywords |
|
Abstract |
Electrically charged particles can be created by the decay of strong enough electric fields, a phenomenon known as the Schwinger mechanism(1). By electromagnetic duality, a sufficiently strong magnetic field would similarly produce magnetic monopoles, if they exist(2). Magnetic monopoles are hypothetical fundamental particles that are predicted by several theories beyond the standard model(3-7) but have never been experimentally detected. Searching for the existence of magnetic monopoles via the Schwinger mechanism has not yet been attempted, but it is advantageous, owing to the possibility of calculating its rate through semi-classical techniques without perturbation theory, as well as that the production of the magnetic monopoles should be enhanced by their finite size(8,9) and strong coupling to photons(2,10). Here we present a search for magnetic monopole production by the Schwinger mechanism in Pb-Pb heavy ion collisions at the Large Hadron Collider, producing the strongest known magnetic fields in the current Universe(11). It was conducted by the MoEDAL experiment, whose trapping detectors were exposed to 0.235 per nanobarn, or approximately 1.8 x 10(9), of Pb-Pb collisions with 5.02-teraelectronvolt center-of-mass energy per collision in November 2018. A superconducting quantum interference device (SQUID) magnetometer scanned the trapping detectors of MoEDAL for the presence of magnetic charge, which would induce a persistent current in the SQUID. Magnetic monopoles with integer Dirac charges of 1, 2 and 3 and masses up to 75 gigaelectronvolts per speed of light squared were excluded by the analysis at the 95% confidence level. This provides a lower mass limit for finite-size magnetic monopoles from a collider search and greatly extends previous mass bounds. |
Address ![sorted by Address field, descending order (down)](img/sort_desc.gif) |
[Acharya, B.; Alexandre, J.; Ellis, J. R.; Fairbairn, M.; Mavromatos, N. E.; Sakellariadou, M.; Sarkar, S.] Kings Coll London, Phys Dept, Theoret Particle Phys & Cosmol Grp, London, England |
Corporate Author |
|
Thesis |
|
Publisher |
Nature Portfolio |
Place of Publication |
|
Editor |
|
Language |
English |
Summary Language |
|
Original Title |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0028-0836 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
|
Conference |
|
Notes |
WOS:000750429600019 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5191 |
Permanent link to this record |