[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-271772-105":59,"doc-detail-271772-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","1f-noise-in-the-heliosphere-a-target-for-punch-science","1/f Noise in the Heliosphere: A Target for PUNCH Science","","The review surveys observations of 1/f noise throughout the heliosphere and frames them in relation to theoretical 1/f models relevant to NASA’s PUNCH mission. Beginning with the spectrum first noted in vacuum-tube voltage fluctuations, it highlights the scale-invariant 1/f form and its appearance in solar-wind interplanetary magnetic-field traces. It discusses mechanisms based on superposition of scale-invariant correlation-time distributions, possible coronal reconnection origins, and dynamo-related inverse-cascade activity, while noting causality challenges for in situ generation. It also links 1/f understanding to key heliospheric physics problems.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/1f-noise-in-the-heliosphere-a-target-for-punch-science/271772/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/1f-noise-in-the-heliosphere-a-target-for-punch-science/271772.png","ImageObject",300,407,{"name":92,"@type":93},"Taylor Morgan","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-11-02","2026-09-15",true,{"@type":102,"interactionType":103,"userInteractionCount":29},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What does 1/f noise (flicker noise) mean in this review?","Question",{"text":112,"@type":113},"It refers to signals whose spectral density scales inversely with frequency, with constant integrated power per octave due to scale invariance.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"Where are 1/f signatures observed in heliospheric contexts?",{"text":117,"@type":113},"The review emphasizes in-situ solar-wind interplanetary magnetic-field observations and discusses evidence extending to the photosphere and corona across compatible frequency ranges.",{"name":119,"@type":110,"acceptedAnswer":120},"What mechanisms are proposed for generating 1/f noise in the heliosphere?",{"text":121,"@type":113},"It highlights a superposition-based mechanism using scale-invariant distributions of correlation times, potentially linked to coronal reconnection and dynamo-related inverse-cascade activity, while also noting limitations of purely in situ generation models.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},271772,1790663744,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":29,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":144,"read_time":145,"preview_page_count":4},1099523885336,"https://ap-avatar.wpscdn.com/davatar_276721f389ce27ea32af1340a28f341c","Solar Physics (2024) 299:169  \n[https://doi.org/10.1007/s1](https://doi.org/10.1007/s1)1207-024-02401-z  \nREVIEW  \n1/f Noise in the Heliosphere: A Target for PUNCH Science  \nJiaming Wang1 · William H. Matthaeus1 · Rohit Chhiber1,2 · Sohom Roy1 · Rayta A. Pradata1 · Francesco Pecora1 · Yan Yang1  \nReceived: 30 August 2024 / Accepted: 31 October 2024 © The Author(s) 2024  \nAbstract  \nWe present a broad review of 1/f noise observations in the heliosphere, and discuss and complement the theoretical background of generic 1/f models as relevant to NASA’s Polarimeter to UNify the Corona and Heliosphere (PUNCH) mission. First observed in the voltage fluctuations of vacuum tubes, the scale-invariant 1/f spectrum has since been identified across a wide array of natural and artificial systems, including heart rate fluctuationsand loudness patterns in musical compositions. In the solar wind the interplanetary magnetic field trace spectrum exhibits 1/f scaling within the frequency range from around 2 × 10−6 Hz to around 10−3 Hz at 1 au. One compelling mechanism for the generation of 1/f noise is the superposition principle, where a composite 1/f spectrum arises from the superposition of a collection of individual power-law spectra characterized by a scale-invariant distribution of correlation times. In the context of the solar wind, such a superposition could originate from scale-invariant reconnection processes in the corona. Further observations have detected 1/f signatures in the photosphere and corona at frequency ranges compatible with those observed at 1 au, suggesting an even lower altitude origin of 1/f spectrum in the solar dynamo itself. This hypothesis is bolstered by dynamo experiments and simulations that indicate inverse cascade activities, which can be linked to successive flux tube reconnections beneath the corona, and are known to generate 1/f noise possibly through nonlocal interactions at the largest scales. Conversely, models positing in situ generation of 1/f signals face causality issues in explaining the low-frequency portion of the 1/f spectrum. Understanding 1/f noise in the solar wind may inform central problems in heliospheric physics, such as the solar dynamo, coronal heating, the origin of the solar wind, and the nature of interplanetary turbulence.  \n1. Introduction  \n1/f noise, otherwise known as “flicker noise”, refers to a signal in which the amplitude of the spectral density P(f ) inversely scales with the frequency f. Such a spectrum has  \nJiaming Wang ()  \n􀀂 W.H. Matthaeus  \n1 Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, USA  \n2 Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA  \nthe unique property that the integrated power per octave remains constant across frequencies. Mathematically, the integration of the spectrum over a frequency range f1 to f2 , i.e.,􀀂 P(f )df ∼􀀂 df/f ∼ log f2 /f1 , depends solely on the ratio f2 /f1 . This total power is insensitive to rescaling of the frequency by an arbitrary factor, a reflection of the scale invariance of the power df/f. The distribution P(f ) ∼ 1/f is often referred to as a scaleinvariant distribution and is observed across a wide array of physical systems (see, e.g., review by Dutta and Horn 1981), including heliospheric plasmas such as the interplanetary magnetic field (Bavassano et al. 1982; Burlaga and Goldstein 1984; Matthaeus and Goldstein 1986) and elsewhere (Matthaeus et al. 2007; Bemporad, Matthaeus, and Poletto 2008) . When the scale-invariant 1/f noise spectrum is observed, it is often fruitful to search fora scale-invariant physical process that produces the observation. In this way the study of 1/f noise can lead to new physical insights. Some examples of such efforts are given in Section 2.  \nThe primitive observations of 1/f-like solar wind magnetic field spectra (Coleman 1968 ; Bavassano et al. 1982; Denskat and Neubauer 1982) revealed a tendency toward spectral indices shallower ","cbCaipthc8niOHPN","https://ap.wps.com/l/cbCaipthc8niOHPN","pdf",1564370,22,"English","# Abstract\n# 1. Introduction\n## Definition and scale invariance of 1/f noise\n## Early heliospheric observations and spectral behavior\n## Relevance to spacecraft missions (PSP and PUNCH)","[{\"question\":\"What does 1/f noise (flicker noise) mean in this review?\",\"answer\":\"It refers to signals whose spectral density scales inversely with frequency, with constant integrated power per octave due to scale invariance.\"},{\"question\":\"Where are 1/f signatures observed in heliospheric contexts?\",\"answer\":\"The review emphasizes in-situ solar-wind interplanetary magnetic-field observations and discusses evidence extending to the photosphere and corona across compatible frequency ranges.\"},{\"question\":\"What mechanisms are proposed for generating 1/f noise in the heliosphere?\",\"answer\":\"It highlights a superposition-based mechanism using scale-invariant distributions of correlation times, potentially linked to coronal reconnection and dynamo-related inverse-cascade activity, while also noting limitations of purely in situ generation models.\"}]","1/f Noise in the Heliosphere: A Target for PUNCH Science | PDF",1789461520,55]