arXiv subjects

G. Stark

Publications and source records attributed to G. Stark.

5 recordsLinked to original sources

arXiv2024

Analysis Facilities White Paper

This white paper presents the current status of the R&D for Analysis Facilities (AFs) and attempts to summarize the views on the future direction of these facilities. These views have been collected through the High Energy Physics (HEP) Software Foundation's (HSF) Analysis Facilities forum, established in March 2022, the Analysis Ecosystems II workshop, that took place in May 2022, and the WLCG/HSF pre-CHEP workshop, that took place in May 2023. The paper attempts to cover all the aspects of an analysis facility.

hep-ex↗

arXiv2023

Ultraviolet photoabsorption in the $B\,{}^3{\Sigma}^- - X\,{}^3{\Sigma}^-$ and $C\,{}^3{\Pi} - X\,{}^3{\Sigma}^-$ band systems of SO sulphur isotopologues

High-resolution far-ultraviolet broadband Fourier-transform photoabsorption spectra of ${}^{32}{\rm S}^{16}{\rm O}$, ${}^{33}{\rm S}^{16}{\rm O}$, ${}^{34}{\rm S}^{16}{\rm O}$, and ${}^{36}{\rm S}^{16}{\rm O}$ are recorded in a microwave discharge seeded with SO$_2$ . The $B{}^3{\Sigma}^-(v=4-30) \leftarrow X{}^3{\Sigma}^-(v=0)$ and $C{}^3{\Pi}(v=0-7) \leftarrow X{}^3{\Sigma}^-(v=0)$ bands are observed or inferred in the 43000 to 51000 cm$^{-1}$ (196 to 233 nm) spectral range. This is the first experimental detection of a $C{}^3{\Pi}(v>2)$ level and of any of these observed bands in an S-substituted isotopologue. Additional measurements of $A{}^3{\Pi}(v=1-3) \leftarrow X{}^3{\Sigma}^-(v=0)$ provide a calibration of the SO column density. Measured band profiles are fitted to an effective-Hamiltonian model of coupled excited $B{}^3{\Sigma}^-$ and $C{}^3{\Pi}$ states along with their predissociation linewidths and absorption band strengths. Electronic-state potential-energy curves and transition moments are deduced. The end result is a list of line frequencies, $f$-values, and dissociation widths describing the far-ultraviolet photodissociation spectrum of SO that is accurate enough for computing atmospheric photolytic isotope-fractionation.

physics.atom-ph↗

arXiv2022

Fourier-transform spectroscopy of $^{13}$C$^{17}$O and deperturbation analysis of the A$^1\Pi$ ($\nu$ = 0 - 3) levels

The high-resolution B$^1\Sigma^+$ - A$^1\Pi$ (0, 0) and (0, 3) emission bands of the less-abundant $^{13}$C$^{17}$O isotopologue have been investigated by Fourier-transform spectroscopy in the visible region using a Bruker IFS 125HR spectrometer at an accuracy 0.003 cm$^{-1}$. These spectra are combined with high-resolution photoabsorption measurements of the $^{13}$C$^{17}$O B$^1\Sigma^+$ $\leftarrow$ X$^1\Sigma^+$ (0, 0), B$^1\Sigma^+$ $\leftarrow$ X$^1\Sigma^+$ (1, 0) and C$^1\Sigma^+$ $\leftarrow$ X$^1\Sigma^+$ (0, 0) bands recorded with an accuracy of 0.01 cm$^{-1}$ using the vacuum ultraviolet Fourier-transform spectrometer, installed on the DESIRS beamline at the SOLEIL synchrotron. In the studied 17,950 - 22,500 cm$^{-1}$ and 86,800 - 92,100 cm$^{-1}$ regions, 480 transitions have been measured. These new experimental data were combined with data from the C $\to$ A and B $\to$ A systems, previously analyzed in 13C17O. The frequencies of 1003 transitions derived from 12 bands were used to analyze the perturbations between the A$^1\Pi$ ($\nu$ = 0 - 3) levels and rovibrational levels of the d$^3\Delta_i$, e$^3\Sigma^-$, a$'{}^3\Sigma^+$, I$^1\Sigma^-$ and D$^1\Delta$ states as well as to a preliminary investigation of weak irregularities that appear in the B$^1\Sigma^+$ ($\nu$ = 0) level. Deperturbed molecular constants and term values of the A$^1\Pi$ state were obtained. The spin-orbit and L-uncoupling interaction parameters as well as isotopologue-independent spin-orbit and rotation-electronic perturbation parameters were derived.

physics.chem-ph↗

arXiv2022

Accessibility in High Energy Physics: Lessons from the Snowmass Process

Accessibility to participation in the high energy physics community can be impeded by many barriers. These barriers must be acknowledged and addressed to make access more equitable in the future. An accessibility survey, the Snowmass Summer Study attendance survey, and an improved accessibility survey were sent to the Snowmass2021 community. This paper will summarize and present the barriers that prevent people from participating in the Snowmass2021 process,recommendations for the various barriers, and discussions of resources and funding needed to enact these recommendations, based on the results of all three surveys, along with personal experiences of the community members.

physics.ed-ph↗

arXiv2022

A Muon Collider Facility for Physics Discovery

Muon colliders provide a unique route to deliver high energy collisions that enable discovery searches and precision measurements to extend our understanding of the fundamental laws of physics. The muon collider design aims to deliver physics reach at the highest energies with costs, power consumption and on a time scale that may prove favorable relative to other proposed facilities. In this context, a new international collaboration has formed to further extend the design concepts and performance studies of such a machine. This effort is focused on delivering the elements of a $\sim$10 TeV center of mass (CM) energy design to explore the physics energy frontier. The path to such a machine may pass through lower energy options. Currently a 3 TeV CM stage is considered. Other energy stages could also be explored, e.g. an s-channel Higgs Factory operating at 125 GeV CM. We describe the status of the R&D and design effort towards such a machine and lay out a plan to bring these concepts to maturity as a tool for the high energy physics community.

physics.acc-ph↗