| 1. |
- Ahdida, C., et al.
(författare)
-
Fast simulation of muons produced at the SHiP experiment using Generative Adversarial Networks
- 2019
-
Ingår i: Journal of Instrumentation. - : IOP PUBLISHING LTD. - 1748-0221 .- 1748-0221. ; 14
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents a fast approach to simulating muons produced in interactions of the SPS proton beams with the target of the SHiP experiment. The SHIP experiment will be able to search for new long-lived particles produced in a 400 GeV/c SPS proton beam dump and which travel distances between fifty metres and tens of kilometers. The SHiP detector needs to operate under ultra-low background conditions and requires large simulated samples of muon induced background processes. Through the use of Generative Adversarial Networks it is possible to emulate the simulation of the interaction of 400 GeV/c proton beams with the SHiP target, an otherwise computationally intensive process. For the simulation requirements of the SHiP experiment, generative networks are capable of approximating the full simulation of the dense fixed target, offering a speed increase by a factor of O(10(6)). To evaluate the performance of such an approach, comparisons of the distributions of reconstructed muon momenta in SHiP's spectrometer between samples using the full simulation and samples produced through generative models are presented. The methods discussed in this paper can be generalised and applied to modelling any non-discrete multi-dimensional distribution.
|
|
| 2. |
- Ahdida, C., et al.
(författare)
-
Sensitivity of the SHiP experiment to Heavy Neutral Leptons
- 2019
-
Ingår i: Journal of High Energy Physics (JHEP). - 1126-6708 .- 1029-8479. ; :4
-
Tidskriftsartikel (refereegranskat)abstract
- Heavy Neutral Leptons (HNLs) are hypothetical particles predicted by many extensions of the Standard Model. These particles can, among other things, explain the origin of neutrino masses, generate the observed matter-antimatter asymmetry in the Universe and provide a dark matter candidate. The SHiP experiment will be able to search for HNLs produced in decays of heavy mesons and travelling distances ranging between O(50 m) and tens of kilometers before decaying. We present the sensitivity of the SHiP experiment to a number of HNL's benchmark models and provide a way to calculate the SHiP's sensitivity to HNLs for arbitrary patterns of flavour mixings. The corresponding tools and data files are also made publicly available.
|
|
| 3. |
- Ahdida, C., et al.
(författare)
-
The experimental facility for the Search for Hidden Particles at the CERN SPS
- 2019
-
Ingår i: Journal of Instrumentation. - : Institute of Physics Publishing (IOPP). - 1748-0221 .- 1748-0221. ; 14
-
Tidskriftsartikel (refereegranskat)abstract
- The Search for Hidden Particles (SHiP) Collaboration has shown that the CERN SPS accelerator with its 400 GeV/c proton beam offers a unique opportunity to explore the Hidden Sector [1-3]. The proposed experiment is an intensity frontier experiment which is capable of searching for hidden particles through both visible decays and through scattering signatures from recoil of electrons or nuclei. The high-intensity experimental facility developed by the SHiP Collaboration is based on a number of key features and developments which provide the possibility of probing a large part of the parameter space for a wide range of models with light long-lived super-weakly interacting particles with masses up to O(10) GeV/c(2) in an environment of extremely clean background conditions. This paper describes the proposal for the experimental facility together with the most important feasibility studies. The paper focuses on the challenging new ideas behind the beam extraction and beam delivery, the proton beam dump, and the suppression of beam-induced background.
|
|
| 4. |
- Milstead, David A., et al.
(författare)
-
The active muon shield in the SHiP experiment
- 2017
-
Ingår i: Journal of Instrumentation. - 1748-0221 .- 1748-0221. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- The SHiP experiment is designed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. An essential task for the experiment is to keep the Standard Model background level to less than 0.1 event after 2 x 10(20) protons on target. In the beam dump, around 10(11) muons will be produced per second. The muon rate in the spectrometer has to be reduced by at least four orders of magnitude to avoid muon-induced combinatorial background. A novel active muon shield is used to magnetically deflect the muons out of the acceptance of the spectrometer. This paper describes the basic principle of such a shield, its optimization and its performance.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Ryden-Aulin, Monica, et al.
(författare)
-
Off-label use of rituximab for systemic lupus erythematosus in Europe
- 2016
-
Ingår i: Lupus Science and Medicine. - : BMJ. - 2053-8790. ; 3:1
-
Forskningsöversikt (refereegranskat)abstract
- Objectives: Rituximab (RTX) is a biological treatment used off-label in patients with systemic lupus erythematosus (SLE). This survey aimed to investigate the off-label use of RTX in Europe and compare the characteristics of patients receiving RTX with those receiving conventional therapy. Methods: Data on patients with SLE receiving RTX were taken from the International Registry for Biologics in SLE retrospective registry and complemented with data on patients with SLE treated with conventional therapy. For nationwide estimates of RTX use in patients with SLE, investigators were asked to provide data through case report forms (CRFs). Countries for which no data were submitted through CRFs, published literature and/or personal communication were used, and for European countries where no data were available, estimates were made on the assumption of similarities with neighbouring countries. Results: The estimated off-label use of RTX in Europe was 0.5%-1.5% of all patients with SLE. In comparison with patients with SLE on conventional therapy, patients treated with RTX had longer disease duration, higher disease activity and were more often treated with immunosuppressives. The most frequent organ manifestations for which either RTX or conventional therapy was initiated were lupus nephritis followed by musculoskeletal and haematological. The reason for treatment was, besides disease control, corticosteroid-sparing for patients treated with conventional therapy. Conclusions: RTX use for SLE in Europe is restrictive and appears to be used as a last resort in patients for whom other reasonable options have been exhausted.
|
|
