20+5
Over a decade after the discovery of the Higgs boson, the hunt for physics beyond the Standard Model faces the possibility that new particles might be too heavy to be seen at the LHC. In this case, they would only leave small non-resonant traces in the measured distributions, that could be detected in high-precision measurements. The theoretical framework that best describes these effects is...
The Milky Way is an excellent laboratory for studying dark matter as its spatial distribution can be inferred by tracing the dance of luminous celestial bodies. We use the Jeans equation to model the rotational velocities of stars measured by the Gaia satellite to constrain the Galactic circular velocity curve. In particular, we exploit the increase of volume and precision in data brought...
Background: With the growing interest of ultra-high dose rate therapy (FLASH-RT) different ionizing particle beams have been considered. With most of the experimental results acquired with electron or photon beams, knowledge on heavier ion use remains sparse.
Our previous work has developed a model for FLASH effect dose threshold estimation. Our results have suggested that, FLASH-RT could...
Background: In the recent years, with the active work of CERN Baltic Group in close collaboration with scientists from Next Ion Medical Machine Study (NIMMS) group of the European Organization for Nuclear Research (CERN), an initiative has been started for an innovative particle therapy center in the Baltic States. To fulfill the initiative, a dedicated working group “Advanced Particle...
The CERN related activities carried out by the group of Photoelectric Phenomena at Vilnius University will be presented
In the scope of ongoing initiatives for the design of a new generation of synchrotron-based accelerators for cancer therapy with ion beams, an analysis of LINAC design has started. LINAC represents a critical element with a strong impact on the performance and cost of the accelerator complex. The goal is to identify alternatives at lower cost and a similar or possibly smaller footprint than...
The Compact Muon Solenoid (CMS) experiment is one of four large experiments at the Large Hadron Collider (LHC) and significant upgrades are planned for all experiments and the accelerator facilities to get ready for the High Luminosity era (HL-LHC). As HL-LHC aims to significantly increase the collision rates, thus providing more data for particle physics experiments, upgrades to handle the...
One of the few neutron spallation facilities in the world capable of delivering neutron spectra is the neutron time-of-flight facility (n_TOF). These spectra are primarily employed in conducting precise neutron-induced cross-section measurements using the time of flight technique. Since its operation began in 2001, the facility has continuously contributed to a diverse array of scientific...
The significant increase in CERN CMS computing requirements for the upcoming High-Luminosity Large Hadron Collider (HL-LHC) upgrade will initiate new challenges in pledged HPC computing infrastructure. Federated TIER2 deployment architecture is set to provide a scalable solution by utilizing Latvia's National Academic Network and distributed computing resources of several academic institutions...
Jet energy response depends on the jet flavor. Flavor-dependent (L5) jet energy corrections compensate for this factor while the flavor uncertainties estimate the mismodelling of individual flavors and propagate this to specific flavor mixes. We derive the L5 corrections for CMS run II on a dataset simulated with Pythia 8 and estimate the flavor uncertainties by comparing the Pythia 8 and...
The effect of high electric fields on the surface of metals can be severe and problematic leading to tip formation and vacuum breakdown. Since these effects relate to electric dipole and polarizability of the surface, they should be studied based on first-principle methods. On the other hand, these methods are computationally demanding and do not scale up to realistic times and dimensions. In...
Future Circular Collider (FCC-ee) is a proposal for 92 km circumference double ring which would generate 50 MW/beam of synchrotron radiation (SR) power. Design studies call for the SR fan to be intercepted every ~5 m with localised absorbers. Compared to the continuous design (in which the synchrotron radiation absorber (SRA) channel is located all around the beam pipe), this layout is...
The detection of ultraviolet (UV) photons is becoming increasingly important in high energy particle physics experiments. Sensitivity to UV photons (wavelength range < 350 nm) is essential for detecting Cherenkov radiation in crystals as well as scintillation light in dark matter and neutrino experiments. Nowadays, scientists are looking for new materials for detectors that can directly detect...
The primary task of the Industry Liaison Officer (ILO) in Latvia is to ignite the interest and to engage in procurement process a growing number of Latvian companies representing relevant-to-CERN industries. The role of ILO involves awareness-building, matchmaking and support to ensure that Latvian business community and wider society can leverage the opportunities presented by CERN's...
LFU studies has been on the forefront of HEP physics analyses in the recent years, due to the reported tension with SM predictions in LHCb measurements for R(µ/e) ratios. Some of the reported tension has been resolved, but a potential discrepancies could still be found in the R(τ/e) and R(τ/µ) ratios. To investigate these decay ratios, ttbar events have been chosen as a source of leptons for...
Pure copper is largely used to manufacture particle accelerator components, such as vacuum devices and accelerating cavities, because it combines excellent electrical and thermal conductivity with good workability and solderability. These components often feature complex geometries, like connectors and internal cooling channels, that can only be manufactured following sophisticated routes that...
This research outlines the recent progresses on the mechanical design and integration of the suspension system of superconducting elements subject to variable loads, with focus on the supports of superconducting dipoles for the rotating transfer line of a carbon ion therapy machine, the so-called gantry.
When designing suspension systems for superconducting elements subject to constant...
Additive manufacturing is a relatively new technology which is changing manufacturing paradigms. It is a more natural way of manufacturing with potential that has not yet been fully discovered in the accelerator community. Furthermore, it is a smarter and greener way of manufacturing where the material and energy are not wasted in extra material removal and chips. Compared to conventional...
Yttrium orthosilicate (Y$_2$Si2O$_5$ or YSO) is one of the scintillator materials that is successfully used in Compact Muon Solenoid (CMS) detectors in the Large Hadron Collider. This material can be chemically modified by substituting yttrium Y$^{3+}$ metal ion(s) with lutetium Lu$^{3+}$ ions, resulting in a range of compositions represented by the formula Lu$_x$Y$_{(1-x)}$SiO$_5$,...
To analyze high-energy collisions that occur in the CMS detector, the particles that come from these collision events need to be identified and reconstructed. This process is done by using the particle-flow (PF) reconstruction algorithm.
The energy response of the CMS detector to particles is non-linear. This effect is particularly prominent for PF hadrons. Hadrons are categorized into...
This study investigates the radiation response of Chemical Vapor Deposition (CVD) diamond, a crucial detector material at CERN. Utilizing Raman, Fourier Transformation Infrared (FTIR), and Luminescence Spectroscopy, we analyzed both non-irradiated and neutron-irradiated CVD diamond samples. The focus was on comparing spectral characteristics, specifically variations in band positions and...
We present recent results from the CMS Standard Model Physics - Vector boson (SMP-V) group. The heavy vector bosons W and Z are the carriers of the weak nuclear force and their properties are tightly coupled to those of other massive particles, such as the Higgs boson and top quark, via quantum corrections.
First, we discuss the experimental methods for vector boson measurements, such as the...
It seems that the literature suggests to go in two opposing directions simultaneously. On the one hand, many papers construct basis-independent quantities, since exactly these quantities appear in the expressions for observables. This means that the mixing angles such as $\tan \beta$ in the Two Higgs Doublet Model must drop out when calculating anything physical. On the other hand, there are...
Additive manufacturing has allowed for production of high precision parts with sophisticated geometry and latest advances in technology has enabled production of parts also from pure copper that adds crucial electrical and electromagnetic properties to the produced parts. But main drawback of additive manufacturing is rough surface of produced parts. Effects on surface roughness by surface...
Riga Technical University Institute of Particle Physics and Accelerator Technology is involved in accelerator projects where our contributions are in accelerator technologies innovation and development as well as in accelerator medical applications. Our team contribute in Innovation Fostering in Accelerator Science and Technology, Heavy Ion Therapy Research and Integration plus and Next Ion...
Certain radionuclides of the chemical element scandium are promising candidates to be used for radionuclide-targeted therapy and positron emission tomography (PET/CT). $^{44}$Sc or $^{43}$Sc can be used for diagnostic imaging purposes and monitoring therapy response and $^{47}$Sc for therapeutic purposes or SPECT diagnostics. In terms of production cross section and cost natural titanium is an...
The Large Hadron Collider (LHC) and its associated experiments, including the Compact Muon Solenoid (CMS), are currently undertaking the Run 3 data collection period, set to end in 2025. This period will be followed by the Long Shutdown 3 (LS3) period (2026-2029), during which the High-Luminosity (HL-LHC) upgrade [1] of the LHC will be installed. In order to cope with the planned increase of...
More than ten years have passed since the discovery of the Higgs boson by the
ATLAS and CMS Collaborations at the CERN Large Hadron Collider at a mass of
around 125 GeV. Since the discovery more than 30 times more Higgses were
produced, thus enabling a further scrutiny of the Higgs-related processes,
studying different Higgs production modes, its interactions to various bosons
and...
Many high electric field applications, like as CERN's Compact Linear Collider, are severely hampered by the occurrence of electrical breakdowns. Electrical discharge arises in the presence of a sufficiently high applied electric field, even at ultra high vacuum circumstances, causing disturbances in the device's operating regime, material damage, and, in general, limiting the device's...
