Academic Journal

Coherence limits and chirp control in long pulse free electron laser oscillator

التفاصيل البيبلوغرافية
العنوان: Coherence limits and chirp control in long pulse free electron laser oscillator
المؤلفون: Y. Socol, A. Gover, A. Eliran, M. Volshonok, Y. Pinhasi, B. Kapilevich, A. Yahalom, Y. Lurie, M. Kanter, M. Einat, B. Litvak
المصدر: Physical Review Special Topics. Accelerators and Beams, Vol 8, Iss 8, p 080701 (2005)
بيانات النشر: American Physical Society, 2005.
سنة النشر: 2005
المجموعة: LCC:Nuclear and particle physics. Atomic energy. Radioactivity
مصطلحات موضوعية: Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
الوصف: We report experimental studies of the spectral linewidth and chirp characteristics of the mm-wave rf radiation of the Israeli Electrostatic-Accelerator free electron laser (EA-FEL), along with theory and numerical simulations. The simulations, matching the experimental data, were carried out using a space-frequency-domain model. EA-FELs have the capacity to generate long pulses of tens microseconds and more, that in principle can be elongated indefinitely (cw operation). Since a cold beam FEL is by nature a “homogeneously broadened laser,” EA-FEL can operate, unlike other kinds of FELs, at a single longitudinal mode (single frequency). This allows the generation of very coherent radiation. The current status of the Israeli Tandem Electrostatic-Accelerator FEL, which is based on an electrostatic Van de Graaff accelerator, allows the generation of pulses of tens microseconds duration. It has been operated recently past saturation, and produced single-mode coherent radiation of record narrow inherent relative linewidth ∼Δf/f=10^{-6} at frequencies near 100 GHz. A frequency chirp was observed during the pulses of tens of microseconds (0.3–0.5 MHz/ms). This is essentially a drifting “frequency-pulling effect,” associated with the accelerator voltage drop during the pulse. Additionally, damped relaxation of the FEL oscillator was experimentally measured at the beginning and the end of the lasing pulse, in good correspondence to our theory and numerical simulations. We propose using the chirped signal of the pulsed EA-FEL for single pulse sweep spectroscopy of very fine resolution. The characteristics of this application are analyzed based on the experimental data.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1098-4402
Relation: https://doaj.org/toc/1098-4402
DOI: 10.1103/PhysRevSTAB.8.080701
URL الوصول: https://doaj.org/article/ecaeff33aaf6425593fcc3f8698566b3
رقم الانضمام: edsdoj.ff33aaf6425593fcc3f8698566b3
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:10984402
DOI:10.1103/PhysRevSTAB.8.080701