The frequency spectrum of Barkhausen noise

Abstract

The spectrum of Barkhausen noise has been measured in iron and analysed using signal analysis techniques. The results suggest that the mean duration of the voltage pulses caused by the domain reversals is less than 5 x 10-5 s and that a domain reversal triggers other domain reversals with a time delay normally of 1 to 2 ms. Delays of up to 10ms do occur. The results agree with those obtained by Sawada. The technique allows detailed information of the dynamic nature of domain reversals to be obtained quickly and with little sample preparation.

Damping parametric instabilities in future gravitational wave detectors by means of electrostatic actuators

“…The permanent magnets attached to the interferometer test masses are known to introduce noise through a number of mechanisms [15,16,17]. In order to eliminate these problems, Advanced LIGO uses Electrostatic Drives (ESDs) for the control of its most sensitive optics.…”

“…The majority of currently operating gravitational wave detectors utilise coil-magnet actuators to control the position and angular orientation of their suspended optics. The permanent magnets attached to the interferometer test masses are known to introduce noise through a number of mechanisms [15,16,17]. In order to eliminate these problems, Advanced LIGO uses Electrostatic Drives (ESDs) for the control of its most sensitive optics.…”

Characterization of the LIGO detectors during their sixth science run

“…S Strigin 34 , A S Stroeer 32 , R Sturani 43,44 , A L Stuver 6 , T Z Summerscales 119 , S Susmithan 37 , P J Sutton 7 , B Swinkels 23 , G Szeifert 81 , M Tacca 27 , D Talukder 45 , L Tang 32 , D B Tanner 16 , S P Tarabrin 8 , R Taylor 1 , A P M ter Braack 9 , M P Thirugnanasambandam 1 , M Thomas 6 , P Thomas 25 , K A Thorne 6 , K S Thorne 60 , E Thrane 1 , V Tiwari 16 , K V Tokmakov 105 , C Tomlinson 72 , A Toncelli 14,30 , M Tonelli 14,30 , O Torre 14,15 , C V Torres 32 , C I Torrie 1,26 , F Travasso 42,83 , G Traylor 6 , M Tse 28 , D Ugolini 120 , C S Unnikrishnan , H Vahlbruch 13 , G Vajente 14,30 , M Vallisneri 60 , J F J van den Brand 9,48 , C Van Den Broeck 9 , S van der Putten 9 , M V van der Sluys 78 , J van Heijningen 9 , A A van Veggel 26…”

The path to the enhanced and advanced LIGO gravitational-wave detectors

“…At intermediate frequencies (40-200 Hz) a combination of sources contributed to the noise limit. Among these were length control noise, thermal noise of the main optics and their suspensions and noise from a non-linear Barkhausen effect (see, e.g., [21]) in the magnet actuators.…”