93 research outputs found
Studies for New Experiments at the CERN M2 Beamline within "Physics Beyond Colliders": AMBER/COMPASS++, NA64mu, MuonE
The "Physics Beyond Colliders (PBC)" study explores fundamental physics
opportunities at the CERN accelerator complex complementary to collider
experiments. Three new collaborations aim to exploit the M2 beamline in the
North Area with existing high-intensity muon and hadron beams, but also aspire
to go beyond the current M2 capabilities with a RF-separated, high intensity
hadron beam, under study. The AMBER/COMPASS++ collaboration proposes an
ambitious program with a measurement of the proton radius with muon beams, as
well as QCD-related studies from pion PDFs / Drell-Yan to cross section
measurements for dark sector searches. Assuming feasibility of the RF-separated
beam, the spectrum of strange mesons would enter a high precision era while
kaon PDFs as well as nucleon TMDs would be accessible via Drell-Yan reactions.
The NA64mu collaboration proposes to search for dark sector mediators such as a
dark scalar A' or a hypothetical Z_mu using the M2 muon beam and complementing
their on-going A' searches with electron beams. The MuonE collaboration intends
to assess the hadronic component of the vacuum polarization via elastic mu-e
scattering, the dominant uncertainty in the determination of (g-2)_mu. An
overview of the three new experimental programs will be presented together with
implications for the M2 beamline and the experimental area EHN2, based on the
studies of the PBC "Conventional Beams" Working Group.Comment: MENU 2019 Proceedings, 7 page
RF-Separated Beam Project for the M2 Beam Line at CERN
Within the framework of the Physics Beyond Colliders initiative at CERN, discussions are underway on the feasibility of producing radio-frequency (RF) separated beams for Phase-2 of the AMBER experiment at the M2 beam line in the North experimental area of the CERN SPS. The technique of RF separation is applied to enrich the content of a certain particle type within a beam consisting of different species at the same momentum. It relies on the fact that each particle type has a different velocity, decreasing with rest mass. The successor of the COMPASS experiment, AMBER, requires for its Phase-2 measurements high-intensity, high-purity kaon (and antiproton) beams, which cannot be delivered with the currently existing conventional M2 beam line. The present contribution introduces the principle of RF separation and explains its dependence on different parameters of beam optics and hardware. The first examination of potential showstoppers for the RF-separated beam implementation is presented, based on the particle production rates, beam line transmission for specific optics settings, limitations for overall beam intensity and purity posed by beam line acceptance and radiation protection. Different beam optics settings have been examined, providing either focused or parallel beams inside the RF cavities. The separation and transmission capability of the different optics settings for realistic characteristics of RF cavities are discussed and the preliminary results of the potential purity and intensity of the RF-separated beam are presented. They illustrate the high importance of an RF-separated kaon beam for many of the AMBER Phase-2 data taking programs, such as spectroscopy, prompt-photon production, Primakoff reactions and kaon charge-radius measurement
Strong suppression of nuclear-charge changing interactions for 18 TeV/ c In ions channeled through a bent Si crystal
Abstract We present experimental results giving evidence for the strong reduction—a factor of more than 20—of nuclear-charge changing interactions for 18 TeV In 49+ ions channeled through a silicon crystal bent to 7.5, 11.9 and 19.8 mrad. A very small fraction of the deflected ions suffer electromagnetic or nuclear interactions leading to proton loss while traversing the 60 mm long crystal, even though its thickness corresponds to about 0.13 nuclear interaction lengths for an amorphous material. By considering the deflected ions only, we show experimentally that the nuclear-charge pickup reaction believed to be induced by virtual photons is a short-range phenomenon
Measurement of the very rare decay
The decay K+→π+νν¯
, with a very precisely predicted branching ratio of less than 10−10
,
is among the best processes to reveal indirect effects of new physics.
The NA62 experiment at CERN SPS is designed to study the K+→π+νν¯
decay and to measure its branching ratio using a decay-in-flight technique.
NA62 took data in 2016, 2017 and 2018, reaching the sensitivity of the Standard Model
for the K+→π+νν¯
decay by the analysis of the 2016 and 2017 data,
and providing the most precise measurement of the branching ratio to date
by the analysis of the 2018 data.
This measurement is also used to set limits on BR(K+→π+X
), where X
is a scalar
or pseudo-scalar particle.
The final result of the BR(K+→π+νν¯
) measurement and its interpretation in terms
of the K+→π+X
decay from the analysis of the full 2016-2018 data set is presented, and future plans and prospects are reviewed
CLIC MDI Overview
This paper gives an introduction to the layout of the CLIC Machine Detector Interface as it has been defined for the CLIC Conceptual Design Report. We concentrate on the specific case of the CLIC_SiD detector, although the push-pull concept for two detectors has been included in the design. Some recent work and developments are described as well. However, for the details we refer to the detailed technical talks at this conference
Physics at the AD/PS/SPS (1/4)
Lecture 1: The CERN injector complex and beams for non-LHC physics.
The various machines and beam lines in the CERN injector complex are presented, from the linacs to the SPS. Special emphasis is given to the beam lines at the PS and SPS machines: AD, North and East Areas, nTOF and CNGS and HiRadMad as well as the ion beams. A short outlook is given to possible future upgrades and projects
Design and Tuning of Secondary Beamlines in the CERN North and East Areas
This document gives guidance for the design and tuning of secondary beam lines at CERN. Important aspects include principles and practical recipes for the design of secondary beam line optics, collimation as well as on secondary and tertiary particle production and the selection of specific particle types. The description of these aspects is kept rather general, although the examples are derived from CERN beam lines in the North Experimental Area at the CERN SPS and the East Area at the PS, as well as sometimes from the by now dismantled West Area. Considerations and constraints concerning choice and integration of equipment are explained with direct reference to the existing equipment and methods at CERN. The same applies to beam control and interlocks. After design and installation follows the commissioning and beam tuning. Practical guidance is given on how to proceed efficiently and effectively, again with the CERN beam lines, equipment and control system in mind. The document concludes with a few atypical and complex examples of beam lines that are or have been operated in the CERN North Area
REDTOP DISCUSSIONS IN THE CONVENTIONAL BEAMS WORKING GROUP
In an EN-EA internal meeting of the Conventional Beams WG on February 19th Reyes Alemany Fernandez presented a preliminary study (together with Brennan Goddard) on possibilities for REDTOP at LEIR. The slides are attached. Bettina Mikulec explained the (im-)possibilities at the PS Booster. On the 5th of March D.Cotte discussed the implications at the PS. The SPS was not considered as the low energy required is not achievable with primary beams at all
The report of the Conventional Beams Working Group to the Physics Beyond Collider Study and to the European Strategy for Particle Physics
This document summarises the main conclusions of the Conventional Beams Working group, which has analysed the beam related and technical requirements and requests in the proposals to the Physics Beyond Colliders study for the North Area at the CERN SPS. We present results from studies on feasibility, requirements, compatibility between proposals and, where possible, the order of magnitude of the costs. The physics interest, sensitivity reach and competitiveness world wide of the proposals is discussed in the BSM and QCD physics working groups, which work in synergy with the Conventional Beams group. The final document will be published in place of this announcement. In the meantime a close-to-final draft will be available as EDMS document number 2053962 as of 18 December
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