A preliminary study of the vegetation of vernal pools of Acadia National Park, Mount Desert Island

We conducted a preliminary floristic study of six vernal pools in Acadia National Park on Mount Desert Island, Maine. Plant species were recorded on three sampling dates from April to October, 2008. Sixty-five vascular plant species from 26 families were recorded. Of these, 27 are considered occasional or uncommon in Acadia National Park. Thirteen species are new reports for vernal pools in the northeastern United States. This represents the first published study of the vernal pool flora of Acadia National Par

Lichens of six vernal pools in Acadia National Park, ME, USA

Whereas lichen-habitat relations have been well-documented globally, literature on lichens of vernal pools is scant. We surveyed six vernal pools at Acadia National Park on Mount Desert Island, Maine, USA for their lichen diversity. Sixty-seven species were identified, including seven species that are new reports for Acadia National Park: Fuscidea arboricola, Hypogymnia incurvoides, Lepraria finkii, Phaeographis inusta, Ropalospora viridis, Usnea flammea, and Violella fucata. Five species are considered uncommon or only locally common in New England: Everniastrum catawbiense, Hypogymnia krogiae, Pseudevernia cladonia, Usnea flammea, and Usnea merrillii. This work represents the first survey of lichens from vernal pools in Acadia National Park and strongly suggests that previous efforts at documenting species at the Park have underestimated its species diversity. More work should be conducted to determine whether a unique assemblage of lichens occurs in association with this unique habitat type

Energy deposition studies for the Upgrade II of LHCb at the CERN Large Hadron Collider

The Upgrade II of the LHCb experiment is proposed to be installed during the CERN Long Shutdown 4, aiming to operate LHCb at 1.5x$10^{34}cm^{-2}s^{-1}$ that is 75 times its design luminosity and reaching an integrated luminosity of about $400 fb^{-1}$ by the end of the High Luminosity LHC era. This increase of the data sample at LHCb is an unprecedented opportunity for heavy flavour physics measurements. A first upgrade of LHCb, completed in 2022, has already implemented important changes of the LHCb detector and, for the Upgrade II, further detector improvements are being considered. Such a luminosity increase will have an impact not only on the LHCb detector but also on the LHC magnets, cryogenics and electronic equipment placed in the IR8. In fact, the LHCb experiment was conceived to work at a much lower luminosity than ATLAS and CMS, implying minor requirements for protection of the LHC elements from the collision debris and therefore a different layout around the interaction point. The luminosity target proposed for the Upgrade II requires to review the layout of the entire insertion region in order to ensure safe operation of the LHC magnets and to mitigate the risk of failure of the electronic devices. The objective of this paper is to provide an overview of the implications of the Upgrade II of LHCb in the experimental cavern and in the tunnel with a focus on the LHCb detector, electronic devices and accelerator magnets

A Preliminary Study of the Vegetation of Vernal Pools of Acadia National Park, Maine, U.S.A

We conducted a preliminary floristic study of six vernal pools in Acadia National Park on Mount Desert Island, Maine. Plant species were recorded on three sampling dates from April to October, 2008. Sixty-five vascular plant species from 26 families were recorded. Of these, 27 are considered occasional or uncommon in Acadia National Park. Thirteen species are new reports for vernal pools in the northeastern United States. This represents the first published study of the vernal pool flora of Acadia National Park

Implications of the Upgrade II of LHCb on the LHC Insertion Region 8: From Energy Deposition Studies to Mitigation Strategies

Starting from LHC Run3, a first upgrade of the LHCb experiment (Upgrade I) will enable oeration with a significantly increased instantaneous luminosity in the LHC Insertion Region 8 (IR8), up to 2 $\cdot$ 10$^{33}$ cm$^{-2}$ s$^{-1}$. Moreover, the proposed second upgrade of the LHCb experiment (Upgrade II) aims at increasing it by an extra factor 7.5 (up to 1.5 $\cdot$ 10$^{34}$ cm$^{-2}$ s$^{-1}$, as of Run 5) and collecting an integrated luminosity of 400fb$^{-1}$ by the end of Run 6. Such an ambitious goal poses challenges not only for the detector but also for the accelerator components. Monte Carlo simulations represent a valuable tool to predict the implications of the radiation impact on the machine, especially for future operational scenarios. A detailed IR8 model implemented by means of the FLUKA code is presented in this study. With such a model, we calculated the power density and dose distributions in the superconducting coils of the LHC final focusing quadrupoles (Q1-Q3) and separation dipole (D1) and we highlight a few critical issues calling for mitigation measures. Our study addresses also the recombination dipole (D2) and the suitability of the present TANb absorber, as well as the proton losses in the Dispersion Suppressor (DS) and their implications

Energy deposition studies in the LHCb insertion region from the validation to a step into the Hilumi challenge

The LHCb (Large Hadron Collider beauty) experiment at CERN aims at achieving a significantly higher luminosity than originally planned by means of two major upgrades: the Upgrade I that took place during the Long Shutdown 2 (LS2) and the Upgrade II foreseen for LS4. Such an increase in instantaneous and integrated luminosity with respect to the design values requires to reassess the radiation exposure of LHC magnets, cryogenics and electronic equipment placed in the Insertion Region 8 (IR8) around LHCb. Monte Carlo simulations are a powerful tool to understand and predict the interaction between particle showers and accelerator elements, especially in case of future scenarios. For this purpose, their validation through the comparison with available measurements is a relevant step. A detailed IR8 model, including the LHCb detector, has been implemented with the FLUKA code. The objective of this study is to evaluate radiation levels due to proton-proton collisions and benchmark the predicted dose values against Beam Loss Monitor (BLM) measurements performed in 2018. Finally, we comment on the upcoming LHC run (Run 3), featuring a first luminosity jump in LHCb.Comment: 13 pages, 17 figure

Energy deposition studies for the LHCb insertion region of the CERN Large Hadron Collider

The LHCb (Large Hadron Collider beauty) experiment at CERN LHC aims at achieving a significantly higher luminosity than originally planned by means of two major upgrades: the Upgrade I that took place during the Long Shutdown 2 (LS2) and the Upgrade II proposed for LS4. Such an increase in instantaneous and integrated luminosity with respect to the design values requires to reassess the radiation exposure of LHC magnets, cryogenics, and electronic equipment placed in the insertion region 8 (IR8) around LHCb. Monte Carlo simulations are a powerful tool to understand and predict the interaction between particle showers and accelerator elements, especially in case of future scenarios. For this purpose, their validation through the comparison with available measurements is a relevant step. A detailed IR8 model, including the LHCb detector, has been implemented with the fluka code. The objective of this study is to evaluate radiation levels due to proton-proton collisions and benchmark the predicted dose values against beam loss monitor measurements performed in 2018. Finally, we comment on the upcoming LHC run (Run 3, from 2022 to 2025), featuring a first luminosity jump in LHCb

Power deposition studies for betatron halo losses in HL-LHC

The Large Hadron Collider (LHC) is equipped with a betatron halo collimation system designed to prevent magnet quenches during periods of reduced beam lifetime. Protons subject to single diffractive scattering in collimators can nevertheless leak into the adjacent dispersion suppressors (DS). In view of the future high-luminosity (HL) upgrade of the LHC, a better understanding of the quench margin in these DS magnets is needed, considering the increased beam current and the resulting higher beam losses of up to 1 MW of power within a few seconds, which the collimation system is designed to withstand. In this contribution, we present FLUKA power deposition simulations for a controlled beam loss experiment at 6.8 TeV, probing the quench level of the superconducting magnets most exposed to collimation losses. The results are compared with the expected power deposition in HL-LHC operation, considering different collimator settings. In particular, we studied the power deposition for relaxed collimator gaps, which are considered as the baseline configuration for initial operation in Run 4