F. Oljemark
A5081347819- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Particle Detector Development and Performance
- Quantum Chromodynamics and Particle Interactions
- Particle Accelerators and Free-Electron Lasers
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- Dark Matter and Cosmic Phenomena
- Distributed and Parallel Computing Systems
- CCD and CMOS Imaging Sensors
- Atomic and Subatomic Physics Research
- Advancements in Semiconductor Devices and Circuit Design
- Electromagnetic Simulation and Numerical Methods
- Electron and X-Ray Spectroscopy Techniques
- X-ray Diffraction in Crystallography
- X-ray Spectroscopy and Fluorescence Analysis
- Relativity and Gravitational Theory
- Particle accelerators and beam dynamics
- Neutrino Physics Research
- Advanced X-ray Imaging Techniques
- Biofield Effects and Biophysics
- Silicon and Solar Cell Technologies
- Nuclear Physics and Applications
- Cosmology and Gravitation Theories
- Gamma-ray bursts and supernovae
University of Helsinki
2015-2024
Helsinki Institute of Physics
2014-2024
Institute of High Energy Physics
2024
A. Alikhanyan National Laboratory
2024
Institute for Nuclear Research and Nuclear Energy
2019
Bulgarian Academy of Sciences
2019
Eötvös Loránd University
2019
Campbell Collaboration
2013
Istituto Nazionale di Fisica Nucleare, Sezione di Genova
2006
TOTEM has measured the differential cross-section for elastic proton-proton scattering at LHC energy of {\srud}s = 7TeV analysing data from a short run with dedicated large {\beta} * optics. A single exponential fit slope B (20:1{\pm}0:2stat {\pm}0:3syst)GeV-2 describes range four-momentum transfer squared |t| 0.02 to 0.33 GeV2. After extrapolation 0, total (24:8{\pm}0:2stat {\pm}1:2syst) mb was obtained. Applying optical theorem and using luminosity measurement CMS, (98:3{\pm}0:2stat...
At the LHC energy of , under various beam and background conditions, luminosities, Roman Pot positions, TOTEM has measured differential cross-section for proton-proton elastic scattering as a function four-momentum transfer squared t. The results different analyses are in excellent agreement demonstrating no sizeable dependence on conditions. Due to very close approach detectors center (≈5σbeam) dedicated run with β* = 90 m, |t|-values down 5·10−3 GeV2 were reached. exponential slope this...
The TOTEM collaboration has measured the proton-proton total cross section at √s=8 TeV using a luminosity-independent method. In LHC fills with dedicated beam optics, Roman pots have been inserted very close to allowing detection of ~90% nuclear elastic scattering events. Simultaneously inelastic rate by T1 and T2 telescopes. By applying optical theorem, (101.7±2.9) mb determined, well in agreement extrapolation from lower energies. This method also allows one derive sections:...
The TOTEM experiment at the LHC has performed first luminosity-independent determination of total proton-proton cross-section . This technique is based on optical theorem and requires simultaneous measurements inelastic rate – accomplished with forward charged-particle telescopes T1 T2 in range 3.1 < |η| 6.5 elastic by detecting outcoming protons Roman Pot detectors. data presented here were collected a dedicated run 2011 special beam optics (β* = 90 m) Pots approaching close enough to...
The TOTEM Experiment will measure the total pp cross-section with luminosity-independent method and study elastic diffractive scattering at LHC. To achieve optimum forward coverage for charged particles emitted by collisions in interaction point IP5, two tracking telescopes, T1 T2, be installed on each side pseudorapidity region 3.1 ⩽ |η| 6.5, Roman Pot stations placed distances of ±147 m ±220 from IP5. Being an independent experiment but technically integrated into CMS, first operate...
The TOTEM experiment has made a precise measurement of the elastic proton-proton differential cross-section at centre-of-mass energy sqrt(s) = 8 TeV based on high-statistics data sample obtained with beta* 90 optics. Both statistical and systematic uncertainties remain below 1%, except for t-independent contribution from overall normalisation. This unprecedented precision allows to exclude purely exponential in range four-momentum transfer squared 0.027 < |t| 0.2 GeV^2 significance greater...
Proton-proton elastic scattering has been measured by the TOTEM experiment at CERN Large Hadron Collider in dedicated runs with Roman Pot detectors placed as close seven times transverse beam size (σbeam) from outgoing beams. After careful study of accelerator optics and detector alignment, |t|, square four-momentum transferred process, determined an uncertainty . In this letter, first results differential cross-section are presented covering a |t|-range 0.36 to 2.5 GeV2. The range < |t|...
The TOTEM collaboration has measured the proton–proton total cross section at $$\sqrt{s}=13~\hbox {TeV}$$ with a luminosity-independent method. Using dedicated $$\beta ^{*}=90~\hbox {m}$$ beam optics, Roman Pots were inserted very close to beam. inelastic scattering rate been by T1 and T2 telescopes during same LHC fill. After applying optical theorem is $$\sigma _\mathrm{tot}=(110.6~\pm ~3.4$$ ) mb, well in agreement extrapolation from lower energies. This method also allows one derive...
Abstract The TOTEM experiment at the LHC has performed first measurement $$\sqrt{s} = 13\,\mathrm{TeV}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt><mml:mo>=</mml:mo><mml:mn>13</mml:mn><mml:mspace /><mml:mi>TeV</mml:mi></mml:mrow></mml:math> of $$\rho $$ xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>ρ</mml:mi></mml:math> parameter, real to imaginary ratio nuclear elastic scattering amplitude $$t=0$$...
The TOTEM collaboration has measured the elastic proton-proton differential cross section ${\rm d}\sigma/{\rm d}t$ at $\sqrt{s}=13$ TeV LHC energy using dedicated $\beta^{*}=90$ m beam optics. Roman Pot detectors were inserted to 10$\sigma$ distance from beam, which allowed measurement of range $[0.04$ GeV$^{2}$$; 4 $GeV$^{2}$$]$ in four-momentum transfer squared $|t|$. efficient data acquisition collect about 10$^{9}$ events precisely measure cross-section including diffractive minimum...
The TOTEM collaboration has measured the proton-proton total cross section at $\sqrt{s}=13$ TeV with a luminosity-independent method. Using dedicated $β^{*}=90$ m beam optics, Roman Pots were inserted very close to beam. inelastic scattering rate been by T1 and T2 telescopes during same LHC fill. After applying optical theorem is $σ_{\rm tot}=(110.6 \pm 3.4$) mb, well in agreement extrapolation from lower energies. This method also allows one derive elastic sections: el} = (31.0 1.7)$ mb...
The TOTEM experiment at the LHC has measured inelastic proton-proton cross-section in a β* = 90 m run with low pile-up. measurement was based on events least one charged particle T2 telescope acceptance of 5.3 < |η| 6.5 pseudorapidity. Combined data from T1 telescope, covering 3.1 4.7, for ⩽ final-state determined to be (70.5 ± 2.9) mb. This includes all central diffractive which maximally 0.25 mb is estimated escape detection telescopes. Based models mass diffraction, total deduced (73.7...
The TOTEM experiment at the CERN LHC has measured elastic proton-proton scattering centre-of-mass energy $\sqrt{s}$ = 8 TeV and four-momentum transfers squared, |t|, from 6 x $10^{-4}$ GeV$^2$ to 0.2 GeV$^2$. Near lower end of |t|-interval differential cross-section is sensitive interference between hadronic electromagnetic amplitudes. This article presents measurement constraints it imposes on functional forms modulus phase amplitude. data exclude traditional Simplified West Yennie formula...
Abstract The proton–proton elastic differential cross section $${\mathrm{d}}\sigma /{\mathrm{d}}t$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>d</mml:mi><mml:mi>σ</mml:mi><mml:mo>/</mml:mo><mml:mi>d</mml:mi><mml:mi>t</mml:mi></mml:mrow></mml:math> has been measured by the TOTEM experiment at $$\sqrt{s}=2.76\hbox { TeV}$$...
The TOTEM experiment at the LHC has performed first measurement $\sqrt{s} = 13$ TeV of $ρ$ parameter, real to imaginary ratio nuclear elastic scattering amplitude $t=0$, obtaining following results: $ρ= 0.09 \pm 0.01$ and 0.10 0.01$, depending on different physics assumptions mathematical modelling. unprecedented precision measurement, combined with total cross-section measurements in an energy range larger than 10 (from 2.76 13 TeV), implied exclusion all models classified published by...
The TOTEM experiment has measured the charged-particle pseudorapidity density dNch/dη in pp collisions at for 5.3<|η|<6.4 events with least one charged particle transverse momentum above 40 MeV/c this range. This extends analogous measurement performed by other LHC experiments to previously unexplored forward η region. refers more than 99% of non-diffractive processes and single double diffractive masses ∼3.4 GeV/c2, corresponding about 95% total inelastic cross-section. been found decrease...
The first double diffractive cross-section measurement in the very forward region has been carried out by TOTEM experiment at LHC with center-of-mass energy of sqrt(s)=7 TeV. By utilizing tracking detectors T1 and T2, which extend up to |eta|=6.5, a clean sample pp events was extracted. From these events, we measured sigma_DD =(116 +- 25) mub for where both systems have 4.7 <|eta|_min < 6.5 .
This paper describes the design and performance of timing detector developed by TOTEM Collaboration for Roman Pots (RPs) to measure Time-Of-Flight (TOF) protons produced in central diffractive interactions at LHC . The measurement TOF allows determination longitudinal position proton interaction vertex its association with one vertices reconstructed CMS detectors. is based on single crystal Chemical Vapor Deposition (scCVD) diamond plates designed about 50 ps time precision. upgrade...
Silicon detectors for the Roman Pots of large hadron collider TOTEM experiment aim full sensitivity at edge where a terminating structure is required electrical stability. This work provides an innovative approach reducing conventional width to less than 100 microns, still using standard planar fabrication technology. The objective this new development decouple electric behaviour surface from sensitive volume within tens microns. explanation basic principle together with experimental...
Proton-proton elastic scattering has been measured by the TOTEM experiment at CERN Large Hadron Collider √s = 7 TeV in special runs with Roman Pot detectors placed as close to outgoing beam seven times transverse size. The differential cross-section measurements are reported |t|-range of 0.36 2.5 GeV2. Extending range data low t values from 0.02 0.33 GeV2, and utilizing luminosity CMS, total proton-proton cross section is be (98.3 ±0.2stat ±2.8syst) mb.
The pseudorapidity density of charged particles dN $$_{ ch }$$ /d $$\eta $$ is measured by the TOTEM experiment in proton–proton collisions at $$\sqrt{s} = 8$$ TeV within range $$3.9<\eta <4.7$$ and $$-6.95<\eta <-6.9$$ . Data were collected a low intensity LHC run with occurring distance 11.25 m from nominal interaction point. data sample expected to include 96–97 % inelastic interactions. measurement reported here considers $$p_T>0$$ MeV/c, produced interactions least one particle...
The TOTEM Experiment is designed to measure the total proton-proton cross-section with luminosity-independent method and study elastic diffractive pp scattering at LHC. To achieve optimum forward coverage for charged particles emitted by collisions in interaction point IP5, two tracking telescopes, T1 T2, are installed on each side of IP pseudorapidity region 3.1 < = |eta | 6.5, special movable beam-pipe insertions - called Roman Pots (RP) placed distances +- 147 m 220 from IP5. This article...
Precise knowledge of the beam optics at LHC is crucial to fulfil physics goals TOTEM experiment, where kinematics scattered protons reconstructed with near-beam telescopes -- so-called Roman Pots (RP). Before being detected, protons' trajectories are influenced by magnetic fields accelerator lattice. Thus precise understanding proton transport key importance for experiment. A novel method evaluation proposed which exploits kinematical distributions elastically observed in RPs. Theoretical...
3D detectors with electrodes penetrating through the silicon wafer and covering edges were tested in SPS beam line X5 at CERN autumn 2003. Detector parameters including efficiency, signal-to-noise ratio, edge sensitivity measured using a telescope as reference system. The sensitive width known equal within less than 10 mum.