The effect of ultrasound pretreatment on some selected physicochemical properties of black cumin (Nigella Sativa)

Background In the present study, the effects of ultrasound pretreatment parameters including irradiation time and power on the quantity of the extracted phenolic compounds quantity as well as on some selected physicochemical properties of the extracted oils including oil extraction efficiency, acidity and peroxide values, color, and refractive index of the extracted oil of black cumin seeds with the use of cold press have been studied. Methods For each parameter, three different levels (30, 60, and 90 W) for the ultrasound power and (30, 45, and 60 min) and for the ultrasound irradiation time were studied. Each experiment was performed in three replications. Results The achieved results revealed that, with enhancements in the applied ultrasound power, the oil extraction efficiency, acidity value, total phenolic content, peroxide value, and color parameters increased significantly (P 0.05). Conclusions In summary, it could be mentioned that the application of ultrasound pretreatment in the oil extraction might improve the oil extraction efficiency, the extracted oil’s quality, and the extracted phenolic compounds content.info:eu-repo/semantics/publishedVersio

Measurement of the permanent electric dipole moment of the neutron

We present the result of an experiment to measure the electric dipole moment EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons (UCN). Our measurement stands in the long history of EDM experiments probing physics violating time reversal invariance. The salient features of this experiment were the use of a Hg-199 co-magnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic field changes. The statistical analysis was performed on blinded datasets by two separate groups while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{\rm n} = (0.0\pm1.1_{\rm stat}\pm0.2_{\rmsys})\times10^{-26}e\,{\rm cm}

Statistical sensitivity of the nEDM apparatus at PSI to n - n' oscillations

The neutron and its hypothetical mirror counterpart, a sterile state degenerate in mass, could spontaneously mix in a process much faster than the neutron β-decay. Two groups have performed a series of experiments in search of neutron - mirror-neutron (n − n')oscillations. They reported no evidence, thereby setting stringent limits on the oscillation time τnn. Later, these data sets have been further analyzed by Berezhiani et al.(2009-2017), and signals, compatible with n - n' oscillations in the presence of mirror magnetic fields, have been reported. The Neutron Electric Dipole Moment Collaboration based at the Paul Scherrer Institute performed a new series of experiments to further test these signals. In this paper, we describe and motivate our choice of run configurations with an optimal filling time of 29 s, storage times of 180 s and 380 s, and applied magnetic fields of 10 µT and 20 µT. The choice of these run configurations ensures a reliable overlap in settings with the previous efforts and also improves the sensitivity to test the signals. We also elaborate on the technique of normalizing the neutron counts, making such a counting experiment at the ultra-cold neutron source at the Paul Scherrer Institute possible. Furthermore, the magnetic field characterization to meet the requirements of this n − n oscillation search is demonstrated. Finally, we show that this effort has a statistical sensitivity to n − n' oscillations comparable to the current leading constraints for B' = 0

Magnetic-field uniformity in neutron electric-dipole-moment experiments

Magnetic field uniformity is of the utmost importance in experiments to measure the electric dipole moment of the neutron. A general parametrization of the magnetic field in terms of harmonic polynomial modes is proposed, going beyond the linear-gradients approximation. We review the main undesirable effects of non-uniformities: depolarization of ultracold neutrons, and Larmor frequency shifts of neutrons and mercury atoms. The theoretical predictions for these effects were verified by dedicated measurements with the single-chamber nEDM apparatus installed at the Paul Scherrer Institute

The n2EDM experiment at the Paul Scherrer Institute

We present the new spectrometer for the neutron electric dipole moment (nEDM) search at the Paul Scherrer Institute (PSI), called n2EDM. The setup is at room temperature in vacuum using ultracold neutrons. n2EDM features a large UCN double storage chamber design with neutron transport adapted to the PSI UCN source. The design builds on experience gained from the previous apparatus operated at PSI until 2017. An order of magnitude increase in sensitivity is calculated for the new baseline setup based on scalable results from the previous apparatus, and the UCN source performance achieved in 2016

Ultrasound-assisted extraction of natural products

Ultrasound-assisted extraction (USAE) is an interesting process to obtain high valuable compounds and could contribute to the increase in the value of some food by-products when used as sources of natural compounds. The main benefits will be a more effective extraction, thus saving energy, and also the use of moderate temperatures, which is beneficial for heat-sensitive compounds. For a successful application of the USAE, it is necessary to consider the influence of several process variables, the main ones being the applied ultrasonic power, the frequency, the extraction temperature, the reactor characteristics, and the solvent-sample interaction. The highest extraction rate is usually achieved in the first few minutes, which is the most profitable period. To optimize the process, rate equations and unambiguous process characterization are needed, aspects that have often been lacking. © 2011 Springer Science+Business Media, LLC.The authors thank the Generalitat Valenciana for their financial support in project PROMETEO/2010/062 and the Caja de Ahorros del Mediterraneo for M.D. Esclapez's pre-doctoral grant.Esclapez Vicente, MD.; García Pérez, JV.; Mulet Pons, A.; Cárcel Carrión, JA.; Esclapez, MD. (2011). Ultrasound-assisted extraction of natural products. Food Engineering Reviews. 3(2):108-120. https://doi.org/10.1007/s12393-011-9036-6S10812032Abad Romero B, Bou-Maroun E, Reparet JM, Blanquet J, Cayot N (2010) Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder. Food Chem 119:459–466Adewuyi YG (2001) Sonochemistry: environmental science and engineering applications. Ind Eng Chem Res 40:4681–4715Atchley AA, Crum LA (1988) Acoustic cavitation and bubble dynamics. In: Suslick KS (ed) Ultrasound, its chemical, physical, and biological effects. VHS Publishers, Weinheim, pp 1–64Arnold G, Leiteritz L, Zahn S, Rohm H (2009) Ultrasonic cutting of cheese: composition affects cutting work reduction and energy demand. Int Dairy J 19:314–320Barbero GF, Liazid A, Palma M, Barroso CG (2008) Ultrasound-assisted extraction of capsaicinoids from peppers. Talanta 75:1332–1337Benedito J, Carcel JA, Sanjuan N, Mulet A (2000) Use of ultrasound to assess Cheddar cheese characteristics. Ultrasonics 38:727–730Benedito J, Carcel JA, Rossello C, Mulet A (2001) Composition assessment of raw meat mixtures using ultrasonics. Meat Sci 57:365–370Bhaskaracharya RK, Kentish S, Ashokkumar M (2009) Selected applications of ultrasonics in food processing. Food Eng Rev 1:31–49Boonkird S, Phisalaphong C, Phisalaphong M (2008) Ultrasound-assisted extraction of capsaicinoids from Capsicum frutescens on a lab- and pilot-plant scale. Ultrason Sonochem 15:1075–1079Cárcel JA, Benedito J, Bon J, Mulet A (2007) High intensity ultrasound effects on meat brining. Meat Sci 76:611–619Cárcel JA, Benedito J, Rosselló C, Mulet A (2007) Influence of ultrasound intensity on mass transfer in apple immersed in a sucrose solution. J Food Eng 78:472–479Cavitus (2009) Grape colour and flavour extraction (Pat. Pend.) for red must extraction http://www.cavitus.com . Crafers. Accessed 10 Jan 2011Chea Chua S, Ping Tan C, Mirhosseini H, Ming Lai O, Long K, Sham Baharin B (2009) Optimization of ultrasound extraction condition of phospholipids from palm-pressed fiber. J Food Eng 92:403–409Chena R, Menga F, Zhang S, Liu Z (2009) Effects of ultrahigh pressure extraction conditions on yields and antioxidant activity of ginsenoside from ginseng. Sep Purif Technol 66:340–346Chivate MM, Pandit AB (1995) Quantification of cavitation intensity in fluid bulk. Ultrason Sonochem 2:19–25Da Porto C, Decorti D (2009) Ultrasound-assisted extraction coupled with under vacuum distillation of flavour compounds from spearmint (carvone-rich) plants: comparison with conventional hydrodistillation. Ultrason Sonochem 16:795–799Da Porto C, Decorti D, Kikic I (2009) Flavour compounds of Lavandula angustifolia L. to use in food manufacturing: Comparison of three different extraction methods. Food Chem 112:1072–1078Domínguez H, Núñez MJ, Lema JM (1994) Enzymatic pretreatment to enhance oil extraction from fruits and oilseeds: a review. Food Chem 49:271–286Dong J, Liu Y, Liang Z, Wanga W (2010) Investigation on ultrasound-assisted extraction of salvianolic acid B from Salvia miltiorrhiza root. Ultrason Sonochem 17:61–65Entezari MH, Kruus P (1994) Effect of frequency on sonochemical reactions. I: oxidation of iodide. Ultrason Sonochem 1:75–79Esclapez MD, Sáez V, Milán-Yáñez D, Tudela I, Louisnard O, González-García J (2010) Sonoelectrochemical treatment of water polluted with trichloroacetic acid: from sonovoltammetry to pre-pilot plant scale. Ultrason Sonochem 17:1010–1020Ferraro V, Cruz IB, Ferreira R, Malcata JFX, Pintado ME, Castro PML (2010) Valorisation of natural extracts from marine source focused on marine by-products: review. Food Res Int 43:2221–2233Fischer CH, Hart EJ, Henglein AJ (1986) Hydrogen/deuterium isotope exchange in the hydrogen deuteride-water system under the influence of ultrasound. Phys Chem 90:3059–3060Garcia-Noguera J, Weller CL, Oliveira FIP, Rodrigues S, Fernandes FAN (2010) Dual-stage sugar substitution in strawberries with a Stevia-based sweetener. Innovative Food Sci Emerg Technol 11:225–230García-Pérez JV, Cárcel JA, de la Fuente-Blanco S, Riera-Franco de Sarabia E (2006) Ultrasonic drying of foodstuff in a fluidized bed: parametric study. Ultrasonics 44:539–543García-Pérez JV, García-Alvarado MA, Carcel JA, Mulet A (2010) Extraction kinetics modeling of antioxidants from grape stalk (Vitis vinifera var. Bobal): Influence of drying conditions. J Food Eng 101:49–58González-García J, Sáez V, Tudela I, Díez-Garcia MI, Esclapez MD, Louisnard O (2010) Sonochemical treatment of water polluted by chlorinated organocompounds. A review. Water 2:28–74Handa SS, Preet S, Khanuja S, Longo G, Rakesh DD (2008) Extraction Technologies for Medicinal and Aromatic Plants. United Nations Industrial Development Organization and the International Centre for Science and High Technology, TriesteHemwimol S, Pavasant P, Shotipruk A (2006) Ultrasound-assisted extraction of anthraquinones from roots of Morinda citrifolia. Ultrason Sonochem 13:543–548Hielscher (2011) Teltow http:// www.hielscher.com . Accessed 10 Jan 2011Hu Y, Wang T, Wang M, Han S, Wan P, Fan M (2008) Extraction of isoflavonoids from Pueraria by combining ultrasound with microwave vacuum. Chem Engin Process 47:2256–2261Ince NH, Tezcanli G, Belen RK, Apikyan PG (2001) Ultrasound as a catalyzer of aqueous reaction systems: the state of the art and environmental applications. Appl Catal B 29:167–176Jadhav D, Rekha BN, Gogate PR, Rathod VK (2009) Extraction of vanillin from vanilla pods: a comparison study of conventional soxhlet and ultrasound assisted extraction. J Food Eng 93:421–426Ji J-b, Lu X-h, Cai M-q, Xu C-c (2006) Improvement of leaching process of Geniposide with ultrasound. Ultrason Sonochem 13:455–462Kanthale PM, Gogate PR, Pandit AB, Wilhelm AM (2003) Mapping of an ultrasonic horn: link primary and secondary effects of ultrasound. Ultrason Sonochem 10:331–335Karki B, Lamsal BP, Jung S, van Leeuwen JH, Pometto AL III, Grewell D, Khanal SK (2010) Enhancing protein and sugar release from defatted soy flakes using ultrasound technology. J Food Eng 96:270–278Kardos N, Luche J-L (2001) Sonochemistry of carbohydrate compounds. Carbohydr Res 332:115–131Kotronarou A, Mills G, Hoffmann MR (1991) Ultrasonic Irradiation of para-Nitrophenol in Aqueous Solution. J Phys Chem 95:3630–3638Kuijpers MWA, Kemmere MF, Keurentjes JTF (2002) Calorimetric study of the energy efficiency for ultrasound-induced radical formation. Ultrasonics 40:675–678Leighton TG (2007) What is ultrasound? Prog Biophys Mol Biol 93:3–83Leonelli C, Mason TJ (2010) Microwave and ultrasonic processing: now a realistic option for industry. Chem Eng Process 49:885–900Li H, Pordesimo L, Weiss J (2004) High intensity ultrasound-assisted extraction of oil from soybeans. Food Res Int 37:731–738Liu J, Li J-W, Tang J (2010) Ultrasonically assisted extraction of total carbohydrates from Stevia rebaudiana Bertoni and identification of extracts. Food Bioprod Process 88:215–221Lianfu Z, Zelong L (2008) Optimization and comparison of ultrasound/microwave assisted extraction (UMAE) and ultrasonic assisted extraction (UAE) of lycopene from tomatoes. Ultrason Sonochem 15:731–737Liazid A, Schwarz M, Varela RM, Palma M, Guillén DA, Brigui J, Macías FA, Barroso CG (2010) Evaluation of various extraction techniques for obtaining bioactive extracts from pine seeds. Food Bioprod Process 88:247–252Londoño-Londoño J, Rodrigues de Lima V, Lara O, Gil A, Crecsynski Pasa TB, Arango GJ, Ramirez Pineda JR (2010) Clean recovery of antioxidant flavonoids from citrus peel: optimizing an aqueous ultrasound-assisted extraction method. Food Chem 119:81–87Lou Z, Wang H, Zhang M, Wang Z (2010) Improved extraction of oil from chickpea under ultrasound in a dynamic system. J Food Eng 98:13–18Louisnard O, González-García J, Tudela I, Klima J, Sáez V, Vargas-Hernández Y (2009) FEM simulation of a sono-reactor accounting for vibrations of the boundaries. Ultrason Sonochem 16:250–259Luque de Castro MD, Priego-Capote F (2007) Analytical Applications of Ultrasound, Vol. 26, Techniques and Instrumentation in Analytical Chemistry. Elsevier Science, AmsterdamMa Y, Ye X, Hao Y, Xu G, Xu G, Liu D (2008) Ultrasound-assisted extraction of hesperidin from Penggan (Citrus reticulata) peel. Ultrason Sonochem 15:227–232Ma Y, Chen J-C, Liu Dong-Hong, Ye X-Q (2009) Simultaneous extraction of phenolic compounds of citrus peel extracts: effect of ultrasound. Ultrason Sonochem 16:57–62Makino K, Mossoba MM, Riesz P (1982) Chemical effects of ultrasound on aqueous solutions. Evidence for hydroxyl and hydrogen free radicals (.cntdot. OH and. cntdot. H) by spin trapping. J Chem Soc 104:3537–3539Margulis MA, Margulis IM (2003) Calorimetric method for measurement of acoustic power absorbed in a volume of liquid. Ultrason Sonochem 10:343–345Martin CJ, Law ANR (1983) Design of thermistor probes for measurement of ultrasound intensity distributions. Ultrasonics 21:85–90Mason TJ, Lorimer JP, Bates DM, Zhao Y (1994) Dosimetry in sonochemistry: the use of aqueous terephthalate ion as a fluorescence monitor. Ultrason Sonochem 1:91–95Meinhardt (2011) Leipzig. http://www.meinhardt-ultraschall.de . Accessed 10 Jan 2011Montalbo-Lomboy M, Khanal SK, van Leeuwen JH, Raman DR, Dunn L Jr, Grewell D Jr (2010) Ultrasonic pretreatment of corn slurry for saccharification: a comparison of batch and continuous Systems. Ultrason Sonochem 17:939–946Mulet A, Cárcel JA, Sanjuán N, Bon J (2003) New food drying technologies. Use of ultrasound. Food Sci Technol Int 9:215–221Naguleswaran S, Vasanthan T (2010) Dry milling of field pea (Pisum sativum L.) groats prior to wet fractionation influences the starch yield and purity. Food Chem 118:627–633Orozco-Solano M, Ruiz-Jiménez J, Luque de Castro MD (2010) Ultrasound-assisted extraction and derivatization of sterols and fatty alcohols from olive leaves and drupes prior to determination by gas chromatography–tandem mass spectrometry. J Chromatogr A 1217:1227–1235Patist A, Bates D (2008) Ultrasonic innovations in the food industry: from the laboratory to commercial production. Innovative Food Sci Emerg Technol 9:147–154Price GJ (1990) The use of ultrasound for the controlled degradation of polymer solutions. In: Mason TJ (ed) Advances in sonochemistry, vol 1. Jai Press, Cambridge, pp 231–287Riener J, Noci G, Cronin DA, Morgan DJ, Lyng JG (2010) A comparison of selected quality characteristics of yoghurts prepared from thermosonicated and conventionally heated milks. Food Chem 119:1108–1113Riera E, Golás Y, Blanco A, Gallego JA, Blasco M, Mulet A (2004) Mass transfer enhancement in supercritical fluids extraction by means of power ultrasound. Ultrason Sonochem 11:241–244Riera E, Blanco A, García J, Benedito J, Mulet A, Gallego-Juárez JA, Blasco M (2010) High-power ultrasonic system for the enhancement of mass transfer in supercritical CO2 extraction processes. Physics Procedia 3:141–146Roldán-Gutiérrez JM, Ruiz-Jiménez J, Luque de Castro MD (2008) Ultrasound-assisted dynamic extraction of valuable compounds from aromatic plants and flowers as compared with steam distillation and superheated liquid extraction. Talanta 75:1369–1375Romdhane M, Gourdon C (2002) Investigation in solid–liquid extraction: influence of ultrasound. Chem Eng J 87:11–19Rong L, Kojima Y, Koda S, Nomura H (2008) Simple quantification of ultrasonic intensity using aqueous solution of phenolphthalein. Ultrason Sonochem 8:11–15Sáez V, Frias-Ferrer A, Iniesta J, Gonzalez-Garcıa J, Aldaz A, Riera E (2005) Chacterization of a 20 kHz sonoreactor. Part I: analysis of mechanical effects by classical and numerical methods. Ultrason Sonochem 12:59–65Sáez V, Frias-Ferrer A, Iniesta J, Gonzalez-Garcıa J, Aldaz A, Riera E (2005) Characterization of a 20 kHz sonoreactor. Part II: analysis of chemical effects by classical and electrochemical methods. Ultrason Sonochem 12:67–72Sahena F, Zaidul ISM, Jinap S, Karim AA, Abbas KA, Norulaini NAN, Omar AKM (2009) Application of supercritical CO2 in lipid extraction–A review. J Food Eng 95:240–253Science Direct Database (2011) www.sciencedirect.com (Data of consulting: February 2011)Soria AC, Villamiel M (2010) Effect of ultrasound on the technological properties and bioactivity of food: a review. Trends Food Sci Technol 21:323–331Starmans DAJ, Nijhuis HH (1996) Extraction of secondary metabolites from plant material: a review. Trends Food Sci Technol 7:191–197Sivakumar V, Lakshmi Anna J, Vijayeeswarri J, Swaminathan G (2009) Ultrasound assisted enhancement in natural dye extraction from beetroot for industrial applications and natural dyeing of leather. Ultrason Sonochem 16:782–789Stanisavljevic IT, Lazic ML, Veljkovic VB (2007) Ultrasonic extraction of oil from tobacco (Nicotiana tabacum L.) seeds. Ultrason Sonochem 14:646–652Sun Y, Liu D, Chen J, Ye X, Yu D (2011) Effects of different factors of ultrasound treatment on the extraction yield of the all-trans-b-carotene from citrus peels. Ultrason Sonochem 18:243–249Suslick KS (2001) Sonoluminescence and sonochemistry. In: Meyers RA (ed) Encyclopedia of physical science and technology, vol 17, 3rd edn. Academic Press, San Diego, pp 363–376Trabelsi F, Ait-Iyazidi H, Berlan J, Fabre PL, Delmas H, Wilhelm AM (1996) Electrochemical determination of the active zones in a high-frequency ultrasonic reactor. Ultrason Sonochem 3:125–130Veillet S, Tomao V, Chemat F (2010) Ultrasound assisted maceration: an original procedure for direct aromatisation of olive oil with basil. Food Chem 123:905–911Velickovic DT, Milenovic DM, Ristic MS, Veljkovic VB (2008) Ultrasonic extraction of waste solid residues from the Salvia sp. Essential oil hydrodistillation. Biochem Eng J 42:97–104Vercet A, Burgos J, Crelier S, Lopez-Buesa P (2001) Inactivation of proteases and lipases by ultrasound. Innovative Food Sci Emerg Technol 2:139–150Vilkhu K, Mawson R, Simons L, Bates D (2008) Applications and opportunities for ultrasound assisted extraction in the food industry—A review. Innovative Food Sci Emerg Technol 9:161–169Vinatoru M (2001) An overview of the ultrasonically assisted extraction of bioactive principles from herbs. Ultrason Sonochem 8:303–313Virot M, Tomao V, Le Bourvellec C, Renard CMCG, Chemat F (2010) Towards the industrial production of antioxidants from food processing by-products with ultrasound-assisted extraction. Ultrason Sonochem 17:1066–1074Wang J, Sun B, Cao Y, Tian Y, Li X (2008) Optimisation of ultrasound-assisted extraction of phenolic compounds from wheat bran. Food Chem 106:804–810Wang L, Weller CL (2006) Recent advances in extraction of nutraceuticals from plants. Trends Food Sci Technol 17:300–312Wei X, Chen M, Xiao Ja, Liu Y, Yu L, Zhang H, Wang Y (2010) Composition and bioactivity of tea flower polysaccharides obtained by different methods. Carbohydr Polym 79:418–422Weissler A, Cooper HW, Snyder S (1950) Chemical effects of ultrasonic waves: oxidation of potassium iodide solution by carbon tetrachloride. J Am Chem Soc 72:1769–1775Wulff-Pérez M, Torcello-Gómez A, Gálvez-Ruíz MJ, Martín-Rodríguez A (2009) Stability of emulsions for parenteral feeding: preparation and characterization of o/w nanoemulsions with natural oils and Pluronic f68 as surfactant. Food Hydrocolloids 23:1096–1102Yang B, Yang H, Li J, Li Z, Jiang Y (2011) Amino acid composition, molecular weight distribution and antioxidant activity of protein hydrolysates of soy sauce lees. Food Chem 124:551–555Yang Y, Zhang F (2008) Ultrasound-assisted extraction of rutin and quercetin from Euonymus alatus (Thunb.) Sieb. Ultrason Sonochem 15:308–313Zhang Z-S, Wang L-J, Li D, Jiao S-S, Chena XD, Maoa Z-H (2008) Ultrasound-assisted extraction of oil from flaxseed. Sep Purif Technol 62:192–198Zhang H-F, Yang X-H, Zhao L-D, Wang Y (2009) Ultrasonic-assisted extraction of epimedin C from fresh leaves of Epimedium and extraction mechanism. Innovative Food Sci Emerg Technol 10:54–60Zhang Q-A, Zhang Z-Q, Yue X-F, Fan X-H, Li T, Chen S-F (2009) Response surface optimization of ultrasound-assisted oil extraction from autoclaved almond powder. Food Chem 116:513–518Zhao S, Kwok K-C, Liang H (2007) Investigation on ultrasound assisted extraction of saikosaponins from Radix Bupleuri. Sep Purif Technol 55:307–312Zhu KX, Sun X-H, Zhou H-M (2009) Optimization of ultrasound-assisted extraction of defatted wheat germ proteins by reverse micelles. J Cereal Sci 50:266–271Zheng L, Sun D-W (2006) Innovative applications of power ultrasound during food freezing processes—a review. Trends Food Sci Technol 17:16–23Zou Y, Xie C, Fan G, Gu Z, Han Y (2010) Optimization of ultrasound-assisted extraction of melanin from Auricularia auricula fruit bodies. Innovative Food Sci Emerg Technol 11:611–61

Tools and techniques for solvent selection: green solvent selection guides

Driven by legislation and evolving attitudes towards environmental issues, establishing green solvents for extractions, separations, formulations and reaction chemistry has become an increasingly important area of research. Several general purpose solvent selection guides have now been published with the aim to reduce use of the most hazardous solvents. This review serves the purpose of explaining the role of these guides, highlighting their similarities and differences. How they can be used most effectively to enhance the greenness of chemical processes, particularly in laboratory organic synthesis and the pharmaceutical industry, is addressed in detail

Johnson-Nyquist noise effects in neutron electric-dipole-moment experiments

Magnetic Johnson-Nyquist noise (JNN) originating from metal electrodes, used to create a static electric field in neutron electric-dipole-moment (nEDM) experiments, may limit the sensitivity of measurements. We present here a dedicated study on JNN applied to a large-scale long-measurement-time experiment with the implementation of a comagnetometry. In this study, we derive surface- and volume-averaged root-mean-square normal noise amplitudes at a certain frequency bandwidth for a cylindrical geometry. In addition, we model the source of noise as a finite number of current dipoles and demonstrate a method to simulate temporal and three-dimensional spatial dependencies of JNN. The calculations are applied to estimate the impact of JNN on measurements with the new apparatus, n2EDM, at the Paul Scherrer Institute. We demonstrate that the performances of the optically pumped Cs133 magnetometers and Hg199 comagnetometers, which will be used in the apparatus, are not limited by JNN. Further, we find that, in measurements deploying a comagnetometer system, the impact of JNN is negligible for nEDM searches down to a sensitivity of 4×10-28ecm in a single measurement; therefore, the use of economically and mechanically favored solid aluminum electrodes is possible