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Related papers: Drift Observations and Mitigation in LCLS-II RF

200 papers

CEA is committed to the design, construction and commissioning of a Medium Energy Beam Transfer line and a superconducting linac (SCL) for SARAF accelerator in order to accelerate 5mA beam of either protons from 1.3 MeV to 35 MeV or…

Accelerator Physics · Physics 2019-10-15 L. Zhao , G. Ferrand , F. Gougnaud , R. Duperrier , N. Pichoff , C. Marchand

PIP-II is an 800 MEV superconducting linac that is in the initial acceleration chain for the Fermilab accelerator complex. The RF system consists of a warm front-end with an ion source, RFQ and buncher cavities along with 25 superconducting…

Accelerator Physics · Physics 2023-11-13 P. Varghese , B. Chase , E. Cullerton , S. Raman , S. Ahmed , P. Hanlet , D. Klepec

The proposed Next Linear Collider (NLC) contains linac systems operating at L,S,C, and X band. This paper describes a wideband modular low-level RF (LLRF) system applicable for all NLC pulsed RF systems. High speed digital IF techniques are…

Accelerator Physics · Physics 2007-05-23 P. Corredoura , C. Adolphsen

We have conducted a photometric monitoring program of 3 field late-L brown dwarfs looking for evidence of non-axisymmetric structure or temporal variability in their photospheres. The observations were performed using Spitzer/IRAC 4.5 and 8…

Resistance drift in phase change materials is characterized in amorphous phase change memory line-cells from 300 K to 125 K range and is observed to follow the previously reported power-law behavior with drift coefficients in the 0.07 to…

Applied Physics · Physics 2020-01-09 Raihan Sayeed Khan , Faruk Dirisaglik , Ali Gokirmak , Helena Silva

This paper presents the design, fabrication, and characterization of broadband liquid crystal (LC) reconfigurable intelligent surfaces (RIS) operating around 60 GHz and scaling up to 750 radiating elements. The RISs employ a delay line…

Signal Processing · Electrical Eng. & Systems 2026-01-19 Julia Schwarzbeck , Robin Neuder , Marc Späth , Alejandro Jiménez-Sáez

We report the results of a low-latency beam phase feed-forward system built to stabilize the arrival time of a relativistic electron beam. The system was operated at the Compact Linear Collider (CLIC) Test Facility (CTF3) at CERN where the…

Accelerator Physics · Physics 2018-02-12 J. Roberts , P. Skowronski , P. N. Burrows , G. B. Christian , R. Corsini , A. Ghigo , F. Marcellini , C. Perry

LISA Pathfinder (LPF) was a technology pioneering mission designed to test key technologies required for gravitational wave detection in space. In the low frequency regime (milli-Hertz and below), where space-based gravitational wave…

We report on an attempt to accurately wavelength calibrate four nights of data taken with the Keck HIRES spectrograph on QSO PHL957, for the purpose of determining whether the fine structure constant was different in the past. Using new…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-15 Kim Griest , Jonathan B. Whitmore , Arthur M. Wolfe , J. Xavier Prochaska , J. Christopher Howk , Geoffrey W. Marcy

The Fermilab Linac accepts the 0.75 MeV H- ions from the front end and accelerates them to 400 MeV for injection into the Booster. Day-to-day drifts of the longitudinal trajectory in the Linac, reconstructed from phase readings of Beam…

Accelerator Physics · Physics 2023-12-14 Sheldon Rego , Ralitsa Sharankova , Alexander Shemyakin

We characterized resistance drift in phase change memory devices in the 80 K to 300 K temperature range by performing measurements on 20 nm thick, ~70-100 nm wide lateral Ge2Sb2Te5 (GST) line cells. The cells were amorphized using 1.5-2.5 V…

Liquid crystal (LC) technology has emerged as a promising solution for large reconfigurable intelligent surfaces (RISs) at millimeter wave (mmWave) bands, offering advantages such as low power consumption, scalability, and continuously…

Signal Processing · Electrical Eng. & Systems 2025-08-18 Bowu Wang , Mohamadreza Delbari , Robin Neuder , Alejandro Jiménez-Sáez , Vahid Jamali

China Spallation Neutron Source(CSNS) target power will upgrade to 500 kW(CSNS-II) from 300kW, energy gain of H-Linac will up to 300 MeV from 80 MeV using about 50 superconductor cavities. LLRF is an important device for controlling the…

Accelerator Physics · Physics 2023-11-17 Zhexin Xie , Kai Guo , Zhencheng Mu , Xinpeng Ma , Nan Gan , Maliang Wan , Bo Wang , Linyan Rong , Hui Zhang , Hexin Wang

The reflecting antenna elements in most reconfigurable intelligent surfaces (RISs) use semiconductor-based (e.g., positive-intrinsic-negative (PIN) diodes and varactors) phase shifters. Although effective, a drawback of this technology is…

Signal Processing · Electrical Eng. & Systems 2025-05-09 Nairy Moghadas Gholian , Mohamadreza Delbari , Vahid Jamali , Arash Asadi

Atmospheric water vapor causes significant undesired phase fluctuations for the Submillimeter Array (SMA) interferometer, particularly in its highest frequency observing band of 690 GHz. One proposed solution to this atmospheric effect is…

Astrophysics · Physics 2007-05-23 D. Y. Kubo , T. R. Hunter , R. D. Christensen , P. I. Yamaguchi

The Fermi National Accelerator Laboratory (Fermilab) Linac accepts 750 keV H- ions from the front end and accelerates them to 400 MeV for injection into the Booster rapid cycling synchrotron. Day-to-day drifts in the beam longitudinal…

Accelerator Physics · Physics 2024-07-25 R. Sharankova , A. Shemyakin , S. Rego

An interferometer system and an imaging system using visible synchrotron radiation (SR) have been installed in HLS II storage ring. Simulations of these two systems are given using Synchrotron Radiation Workshop(SRW) code. With these two…

Accelerator Physics · Physics 2016-09-21 Kai Tang , Bao-Gen Sun , Yong-Liang Yang , Ping Lu , Lei-Lei Tang , Fang-Fang Wu , Chao-Cai Cheng , Jia-Jun Zheng , Hao Li

The rapid cycling synchrotron (RCS) is part of China Spallation Neutron Source (CSNS). The RCS provides 1.6GeV protons with a repetition rate of 25Hz. The RF system in RCS is mainly composed of a ferrite loaded RF cavity, a high power…

Accelerator Physics · Physics 2014-04-11 Li Xiao , Sun Hong , Long Wei , Zhao Fa-Cheng , Zhang Chun-Lin

(abridged) We perform photometric time-series analysis of a sample of ten early to mid-L dwarfs in the field over three years of $K_s$-band observations with the OMEGA 2000 infrared camera of the 3.5m telescope on Calar Alto Observatory…

Solar and Stellar Astrophysics · Physics 2015-06-22 Belén López Martí , María Rosa Zapatero Osorio