MoEDAL Detector Research Articles

Search for highly-ionizing particles in pp collisions at the LHC’s Run-1 using the prototype MoEDAL detector

A search for highly electrically charged objects (HECOs) and magnetic monopoles is presented using 2.2 hbox {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}.

Detecting long-lived multi-charged particles in neutrino mass models with MoEDAL

A certain class of neutrino mass models predicts long-lived particles whose electric charge is four or three times larger than that of protons. Such particles, if they are light enough, may be produced at the LHC and detected. We investigate the possibility of observing those long-lived multi-charged particles with the MoEDAL detector, which is sensitive to long-lived particles with low velocities (beta ) and a large electric charge (Z) with Theta equiv beta /Z lesssim 0.15. We demonstrate that multi-charged scalar particles with a large Z give three-fold advantage for MoEDAL; reduction of Theta due to strong interactions with the detector, and enhancement of the photon-fusion process, which not only increases the production cross-section but also lowers the average production velocity, reducing Theta further. To demonstrate the performance of MoEDAL on multi-charged long-lived particles, two concrete neutrino mass models are studied. In the first model, the new physics sector is non-coloured and contains long-lived particles with electric charges 2, 3 and 4. A model-independent study finds MoEDAL can expect more than 1 signal event at the HL-LHC (L = 300hbox {fb}^{-1}) if these particles are lighter than 600, 1100 and 1430 GeV, respectively. These compare with the current ATLAS limits 650, 780 and 920 GeV for L = 36hbox {fb}^{-1}. The second model has a coloured new physics sector, which possesses long-lived particles with electric charges 4/3, 7/3 and 10/3. The corresponding MoEDAL’s mass reaches at the HL-LHC are 1400, 1650 and 1800 GeV, respectively, which compare with the current CMS limits 1450, 1480 and 1510 GeV for L = 36hbox {fb}^{-1}. In a model-specific study we explore the parameter space of neutrino mass generation models and identify the regions that can be probed with MoEDAL at the end of Run-3 and the High-Luminosity LHC.

SUSY discovery prospects with MoEDAL

We present a preliminary study on the possibility to search for massive long-lived electrically charged particles at the MoEDAL detector. MoEDAL is sensitive to highly ionising objects such as magnetic monopoles or massive (meta-)stable electrically charged particles and we focus on the latter in this paper. Requirements on triggering or reducing the cosmic-ray and cavern background, applied in the ATLAS and CMS analyses for long-lived particles, are not necessary at MoEDAL, due to its completely different detector design and extremely low background. On the other hand, MoEDAL requires slow-moving particles, resulting in sensitivity to massive states with typically small production cross sections. Using Monte Carlo simulations, we compare the sensitivities of MoEDAL versus ATLAS/CMS for various long-lived particles in supersymmetric models, and we seek a scenario where MoEDAL can provide discovery reach complementary to ATLAS and CMS.

Prospects of searches for long-lived charged particles with MoEDAL

We study the prospects of searches for exotic long-lived particles with the MoEDAL detector at the LHC, assuming the integrated luminosity of 30 fb^{-1} that is expected at the end of Run 3. MoEDAL incorporates nuclear track detectors deployed a few metres away from the interaction point, which are sensitive to any highly-ionizing particles. Hence MoEDAL is able to detect singly- or doubly-charged particles with low velocities beta < 0.15 or < 0.3, respectively, and lifetimes larger than {{mathcal {O}}}(1) ,mathrm{m}/c. We examine the MoEDAL sensitivity to various singly-charged supersymmetric particles with long lifetimes and to several types of doubly-charged long-lived particles with different spins and SU(2) charges. We compare the prospective MoEDAL mass reaches to current limits from ATLAS and CMS, which involve auxiliary analysis assumptions. MoEDAL searches for doubly-charged fermions are particularly competitive.

Searching for heavy neutrinos with the MoEDAL-MAPP detector at the LHC

We present a strategy for searching for heavy neutrinos at the Large Hadron Collider using the MoEDAL Experiment's MAPP detector. We hypothesize the heavy neutrino to be a member of a fourth generation lepton doublet, with the electric dipole moment (EDM) introduced within a dimension-five operator. In this model the heavy neutrino is produced in association with a heavy lepton. According to our current experimental and theoretical understanding, the electric dipole moment of this heavy neutrino may be as high as 10−15e cm. Taking advantage of the sensitivity of MoEDAL detector, we examine the possibility of detecting such a heavy neutrino in the MAPP as an apparently fractionally charged particle, via ionization due to the neutrino's EDM.

The MoEDAL experiment: a new light on the high-energy frontier.

MoEDAL is a pioneering LHC experiment designed to search for anomalously ionizing messengers of new physics, such as the magnetic monopole. After a test run at 8 TeV centre-of-mass energy (Ecm), it started official data taking at the LHC at an Ecm of 13 TeV, in 2015. Its groundbreaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; do topological particles exist; and what is the nature of dark matter? After a brief introduction, MoEDAL's progress to date will be reported, including its past, current and expected future physics output. Additionally, an upgrade to the MoEDAL detector consisting of two new subdetectors: MAPP (MoEDAL Apparatus for Penetrating Particles) now being prototyped at IP8; and MALL (MoEDAL Apparatus for very long-lived particles), will be presented. Finally, a possible astroparticle extension to MoEDAL, called Cosmic-MoEDAL, will be briefly described. This high altitude detector will allow the search for magnetic monopoles to be continued from the TeV scale to the GUT scale. This article is part of a discussion meeting issue 'Topological avatars of new physics'.

Physical implications of electroweak monopole.

The electroweak monopole in the standard model, the existence, characteristic features, cosmological production and physical implications are discussed. The discovery of the Higgs particle has been thought to be the 'final' test of the standard model. If the standard model is correct, however, it must have the electroweak monopole as the electroweak generalization of the Dirac monopole. This means that the detection of this monopole should become the final and topological test of the standard model. If detected, it becomes the first magnetically charged and stable topological elementary particle in the history of physics. Moreover, it has deep implications in physics. In cosmology, it could generate the primordial magnetic black holes which could explain the dark matter, become the seed of the large-scale structures of the universe, and be the source of the intergalactic magnetic field. Just as importantly, it could generate the hitherto unknown magnetic current which could have huge practical applications. Furthermore, the existence of the monopole requires us to reformulate the perturbative expansion in quantum field theory. This makes the detection of the electroweak monopole a most urgent issue. We discuss useful tips for the MoEDAL detector at LHC and similar experiments on how to detect the monopole successfully. This article is part of a discussion meeting issue 'Topological avatars of new physics'.

The MoEDAL Experiment at the LHC - Searching for Physics Beyond the Standard Model

MoEDAL is a pioneering experiment designed to search for highly ionizing messengers of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles, that are predicted to exist in a plethora of models beyond the Standard Model. It started data taking at the LHC at a centre-of-mass energy of 13 TeV, in 2015. MoEDAL’s ground breaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; and what is the nature of dark matter. MoEDAL’s purpose is to meet such far-reaching challenges at the frontier of the field. We will present an overview of the MoEDAL detector, including the planned MAPP subdetector, as well as MoEDAL’s physics program. The concluding section highlights our first physics results on Magnetic Monopole production, that are the world’s best for Monopoles with multiple magnetic charge.

Physics reach of MoEDAL at LHC: magnetic monopoles, supersymmetry and beyond

MoEDAL is a pioneering experiment designed to search for highly ionising messengers of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles, that are predicted to exist in a plethora of models beyond the Standard Model. Its ground-breaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as, are there extra dimensions or new symmetries, what is the mechanism for the generation of mass, does magnetic charge exist, what is the nature of dark matter, and, how did the big-bang develop at the earliest times. MoEDAL's purpose is to meet such far-reaching challenges at the frontier of the field. The physics reach of the existing MoEDAL detector is discussed, giving emphasis on searches for magnetic monopoles, supersymmetric (semi)stable partners, doubly charged Higgs bosons, and exotic structures such as black-hole remnants in models with large extra spatial dimensions and D-matter in some brane theories.

Search for magnetic monopoles with the MoEDAL prototype trapping detector in 8 TeV proton-proton collisions at the LHC

The MoEDAL experiment is designed to search for magnetic monopoles and other highly-ionising particles produced in high-energy collisions at the LHC. The largely passive MoEDAL detector, deployed at Interaction Point 8 on the LHC ring, relies on two dedicated direct detection techniques. The first technique is based on stacks of nuclear-track detectors with surface area $\sim$18 m$^2$, sensitive to particle ionisation exceeding a high threshold. These detectors are analysed offline by optical scanning microscopes. The second technique is based on the trapping of charged particles in an array of roughly 800 kg of aluminium samples. These samples are monitored offline for the presence of trapped magnetic charge at a remote superconducting magnetometer facility. We present here the results of a search for magnetic monopoles using a 160 kg prototype MoEDAL trapping detector exposed to 8 TeV proton-proton collisions at the LHC, for an integrated luminosity of 0.75 fb$^{-1}$. No magnetic charge exceeding $0.5g_{\rm D}$ (where $g_{\rm D}$ is the Dirac magnetic charge) is measured in any of the exposed samples, allowing limits to be placed on monopole production in the mass range 100 GeV$\leq m \leq$ 3500 GeV. Model-independent cross-section limits are presented in fiducial regions of monopole energy and direction for $1g_{\rm D}\leq|g|\leq 6g_{\rm D}$, and model-dependent cross-section limits are obtained for Drell-Yan pair production of spin-1/2 and spin-0 monopoles for $1g_{\rm D}\leq|g|\leq 4g_{\rm D}$. Under the assumption of Drell-Yan cross sections, mass limits are derived for $|g|=2g_{\rm D}$ and $|g|=3g_{\rm D}$ for the first time at the LHC, surpassing the results from previous collider experiments.

Simulation of the MoEDAL experiment

The MoEDAL experiment (Monopole and Exotics Detector at the LHC) is designed to directly search for magnetic monopoles and other highly ionising stable or meta-stable particles at the LHC. The MoEDAL detector comprises an array of plastic track detectors and aluminium trapping volumes around the P8 intersection region, opposite from the LHCb detector. TimePix devices are also installed for monitoring of the experiment. As MoEDAL mostly employs passive detectors the software development focusses on particle simulation, rather than digitisation or reconstruction. Here, we present the current status of the MoEDAL simulation software. Specifically, the development of a material description of the detector and simulations of monopole production and propagation at MoEDAL.

The MoEDAL experiment at the LHC. Searching beyond the standard model

MoEDAL is a pioneering experiment designed to search for highly ionizing avatars of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles. Its groundbreaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; what is the nature of dark matter; and, how did the big-bang develop. MoEDAL’s purpose is to meet such far-reaching challenges at the frontier of the field.The innovative MoEDAL detector employs unconventional methodologies tuned to the prospect of discovery physics. The largely passive MoEDAL detector, deployed at Point 8 on the LHC ring, has a dual nature. First, it acts like a giant camera, comprised of nuclear track detectors - analyzed offline by ultra fast scanning microscopes - sensitive only to new physics. Second, it is uniquely able to trap the particle messengers of physics beyond the Standard Model for further study. MoEDAL’s radiation environment is monitored by a state-of-the-art real-time TimePix pixel detector array. A new MoEDAL sub-detector to extend MoEDAL’s reach to millicharged, minimally ionizing, particles (MMIPs) is under study Finally we shall describe the next step for MoEDAL called Cosmic MoEDAL, where we define a very large high altitude array to take the search for highly ionizing avatars of new physics to higher masses that are available from the cosmos.

The MoEDAL Experiment at the LHC – a New Light on the Terascale Frontier

MoEDAL is a pioneering experiment designed to search for highly ionizing avatars of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles. Its groundbreaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; what is the nature of dark matter; and, how did the big-bang develop. MoEDAL's purpose is to meet such far-reaching challenges at the frontier of the field. The innovative MoEDAL detector employs unconventional methodologies tuned to the prospect of discovery physics. The largely passive MoEDAL detector, deployed at Point 8 on the LHC ring, has a dual nature. First, it acts like a giant camera, comprised of nuclear track detectors – analyzed offline by ultra fast scanning microscopes – sensitive only to new physics. Second, it is uniquely able to trap the particle messengers of physics beyond the Standard Model for further study. MoEDAL's radiation environment is monitored by a state-of-the-art real-time TimePix pixel detector array. A new MoEDAL sub-detector to extend MoEDAL's reach to millicharged, minimally ionizing, particles (MMIPs) is under study.

The MoEDAL experiment - a new light on LHC physics

In 2010 the MoEDAL experiment at the Large Hadron Collider (LHC) was unanimously approved by CERN’s Research Board to start data taking in 2015. MoEDAL is a pioneering experiment designed to search for highly ionizing messengers of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles. Its groundbreaking physics program defines a number of scenarios that yield potentially revolutionary insights into foundational questions. MoEDAL’s purpose is to meet such far-reaching challenges at the frontier of the field. The innovative MoEDAL detector is tuned to the prospect of discovery physics. The largely passive MoEDAL detector, deployed at Point 8 on the LHC ring, has a dual nature. First, it acts like a giant camera, comprised of nuclear track detectors - analyzed offline by ultra fast scanning microscopes – sensitive only to new physics. Second, it is uniquely able to trap the particle harbingers of new physics beyond the Standard Model for further study. MoEDAL’s radiation environment is monitored by a state-of-the-art real-time TimePix pixel detector array.

The MoEDAL experiment - a new light on LHC physics

In 2010 the MoEDAL experiment at the Large Hadron Collider (LHC) was unanimously approved by CERN’s Research Board to start data taking in 2015. MoEDAL is a pioneering experiment designed to search for highly ionizing messengers of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles. Its groundbreaking physics program defines a number of scenarios that yield potentially revolutionary insights into foundational questions. MoEDAL’s purpose is to meet such far-reaching challenges at the frontier of the field. The innovative MoEDAL detector is tuned to the prospect of discovery physics. The largely passive MoEDAL detector, deployed at Point 8 on the LHC ring, has a dual nature. First, it acts like a giant camera, comprised of nuclear track detectors - analyzed offline by ultra fast scanning microscopes – sensitive only to new physics. Second, it is uniquely able to trap the particle harbingers of new physics beyond the Standard Model for further study. MoEDAL’s radiation environment is monitored by a state-of-the-art real-time TimePix pixel detector array.

The physics programme of the MoEDAL experiment at the LHC

The MoEDAL experiment at Point 8 of the LHC ring is the seventh and newest LHC experiment. It is dedicated to the search for highly-ionizing particle avatars of physics beyond the Standard Model, extending significantly the discovery horizon of the LHC. A MoEDAL discovery would have revolutionary implications for our fundamental understanding of the Microcosm. MoEDAL is an unconventional and largely passive LHC detector comprised of the largest array of Nuclear Track Detector stacks ever deployed at an accelerator, surrounding the intersection region at Point 8 on the LHC ring. Another novel feature is the use of paramagnetic trapping volumes to capture both electrically and magnetically charged highly-ionizing particles predicted in new physics scenarios. It includes an array of TimePix pixel devices for monitoring highly-ionizing particle backgrounds. The main passive elements of the MoEDAL detector do not require a trigger system, electronic readout, or online computerized data acquisition. The aim of this paper is to give an overview of the MoEDAL physics reach, which is largely complementary to the programs of the large multipurpose LHC detectors ATLAS and CMS.