Analysis of the Solar Flare Index for Solar Cycles 18-24: Extremely Deep Gnevyshev Gap in the Chromosphere

We study the solar flare index (SFI) for the solar cycles 18\,--\,24. We find that SFI has deeper Gnevyshev gap (GG) in its first principal component than other atmospheric parameters. The GG is extremely clear especially in the even cycles. The GG of the SFI appears about a half year later as a drop in the interplanetary magnetic field near the Earth and in the geomagnetic Ap-index. The instantaneous response of the magnetic field to solar flares, however, shows about two to three days after the eruption as a high, sharp peak in the cross-correlation of the SFI and Ap-index and as a lower peak in SFI vs. IMF B cross-correlation. We confirm these rapid responses using superposed-epoch analysis. The most active flare cycles during 1944-2020 are the Cycles 19 and 21. The Cycle 18 has very strong SFI days as much as Cycle 22, but it has least nonzero SFI days in the whole interval. Interestingly Cycle 20 can be compared to the Cycles 23 and 24 in its low flare activity, although it locates between the most active SFI cycles.Comment: accepted to Solar Physics, 25 pages, 16 figure

Pulssikuparointilinjan toiminta sekä prosessin seurantajärjestelmän suunnittelu ja toteutus

Tiivistelmä. Työn tavoitteena oli Aspocomp Group Oyj:llä sijaitsevan pulssikuparointilinjan nykytilanteen kartoittaminen sekä linjan seurattavuuden parantaminen erilaisten datan hankintaratkaisujen avulla. Ratkaisuissa pyrittiin käyttämään menetelmiä, jotka ovat sovellettavissa myös tehtaan muille prosessilinjoille. Työn teoriaosuudessa perehdyttiin monikerrospiirilevyn valmistamisen päävaiheisiin, elektrolyyttiseen pinnoitukseen, sekä erityisesti pulssikuparointilinjan toimintaan. Lisäksi käytiin läpi työn kokeellisessa osuudessa käytettäviä tilastollisia testejä ja datan hankintamenetelmiä. Kokeellisessa osuudessa tarkasteltiin pulssikuparointilinjan nykytilannetta kerättävän aineiston sekä erilaisten tilastollisten testien avulla. Samalla tutkittiin myös hielaboratoriossa suoritettavien kuparimittausten luotettavuutta. Kokeellisen osuuden loppupuolella pulssikuparointilinjalle suunniteltiin ja toteutettiin pilvipohjainen monitorointijärjestelmä. Pulssikuparointilinjan aineistossa havaitut ilmiöt olivat teorian mukaisia, mutta huomioitavaa oli aineistossa esiintyvä suuri vaihtelu. Tutkimalla käytettyä mittausmenetelmää sekä erien ja tuotteiden sisäistä vaihtelua, voitiin vaihtelun todeta johtuvan toistaiseksi tuntemattomista olosuhdetekijöistä. Kokeellisen osuuden loppupuolella toteutetut pulssikuparointilinjan monitorointijärjestelmät eivät ole työn kirjoittamisen aikaan vielä täysin valmiita. Tästä huolimatta voidaan todeta niiden tuovan tulevaisuudessa lisää työkaluja datan analysointiin antaen näin mahdollisuuksia linjan vaihteluvälien havainnointiin sekä vaihtelua selittävien tekijöiden löytämiseen.The operation of pulse plating line and the design and implementation of the process monitoring system. Abstract. The goal of this work was to study the current state of a pulse plating line located at Aspocomp Group Oyj and to utilize different data acquisition methods to improve the process traceability. The data acquisition methods were selected in a way that they are applicable on other process lines as well. The theory part of the work was focused on basics of multilayer circuit board manufacturing, electroplating and especially the pulse plating process. The theory behind used statistical tests and data acquisition methods in the experimental part was also discussed. In the experimental part the current state of pulse plating process was studied with a collected data set and different statistical methods. Simultaneously the reliability of the used plating thickness measurement method in the cross-sectional laboratory was analysed. In the end of the experimental part a monitoring system for the pulse plating line was planned and implemented. The observations within the data set were in line with theory, but a notable amount of deviation was noticed. By studying the used measurement method and deviations inside the products and batches it could be stated that the deviation is caused by unknown circumstance factors. At the end of the experimental part a monitoring system for the pulse plating line was implemented. During the end of this work the visualisations of the monitoring system are not quite ready. Despite this it can already be stated that it will bring more tools to data analysis and help improve process traceability

Measuring the spin of the primary black hole in OJ287

The compact binary system in OJ287 is modelled to contain a spinning primary black hole with an accretion disk and a non-spinning secondary black hole. Using Post Newtonian (PN) accurate equations that include 2.5PN accurate non-spinning contributions, the leading order general relativistic and classical spin-orbit terms, the orbit of the binary black hole in OJ287 is calculated and as expected it depends on the spin of the primary black hole. Using the orbital solution, the specific times when the orbit of the secondary crosses the accretion disk of the primary are evaluated such that the record of observed outbursts from 1913 up to 2007 is reproduced. The timings of the outbursts are quite sensitive to the spin value. In order to reproduce all the known outbursts, including a newly discovered one in 1957, the Kerr parameter of the primary has to be $0.28 \pm 0.08$. The quadrupole-moment contributions to the equations of motion allow us to constrain the `no-hair' parameter to be $1.0\:\pm\:0.3$ where 0.3 is the one sigma error. This supports the `black hole no-hair theorem' within the achievable precision. It should be possible to test the present estimate in 2015 when the next outburst is due. The timing of the 2015 outburst is a strong function of the spin: if the spin is 0.36 of the maximal value allowed in general relativity, the outburst begins in early November 2015, while the same event starts in the end of January 2016 if the spin is 0.2Comment: 12 pages, 6 figure