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1 TOSCASTSMUniversidaddeExtremadura:LaureLefèvreFebruary2015) ABSTRACT: The International Sunspot Number forms the longest solar time series currently available. It provides an essential reference for understanding and quantifying how the solar output has varied over decades and centuries and thus for assessing the variations of the main natural forcing on the Earth climate. However, the recent "proxy breakdown" between supposedly well-known solar indices has proven that a 1D source of information might not always be sufficient when trying to understand the Sun's behavior over time. In this context, and thanks to the TOSCA COST action, L. Lefèvre is working with J. Vaquero, A. Aparicio, V. Carrasco and M. Gallego to go beyond the SSN series. These are the first steps towards the construction of a multi-parametric time series of multiple sunspot and sunspot group properties over more than a century, allowing to reconstruct and extend the current 1-D SSN series. By bringing new spatial, morphological and evolutionary information, such a data set should bring major advances for the modeling of the solar dynamo and solar irradiance. PURPOSEOFTHESTSM: The purpose of this scientific mission is to increase the collaboration between the Royal Observatory of Belgium and the Universidad de Extremadura in the use of historical sunspot catalogues. Although there are a large number of these sunspot catalogs, a global evaluation Lefèvre Clette, 2014) showed that they suffer from multiple limitations: finite or fragmented time coverage, limited temporal overlap between catalogs and even more importantly, a mismatch in contents and conventions. Aparicio et al. 2014) have recently published data about the sunspot number and the area of the Madrid Observatory 110 year approximately), but have not yet exploited the sunspot catalogues that were made by the Madrid Observatory. We are here referring to two catalogues: the Aguilar Catalogue ) and the Modern Catalogue ). At the time of the start of the mission, the Aguilar Catalogue is digitized and the Modern catalogue is only partially digitized. This STSM thus enables an initial analysis of these recovered catalogues and try a first comparison of these catalogues with other available catalogues on the same period. DESCRIPTION OF THE WORK CARRIED OUT DURING THE STSM A. Aparicio, and J. Vaquero explained the contents and conventions of the Aguilar catalogue and the Modern catalogue. 1/Analysis of the data in the Aguilar catalogue: Madrid Observatory I developed algorithms to automatically detect remaining problems in the catalogue. This catalogue presents observations by spots, and they are grouped in groups of spots. Each of these groups has a Cortie classification Cortie, 1901, Carrasco et al., 2015).

2 Table 1 shows the contents of the Aguilar catalogue: Fecha Nºdel cliché Nº#del# grupo## Año# Mes# Hora Día# h# m# Latitude Aust Boreal# ral# º)# º)# almeridiano centralº) Absoluta# E# W# Absoluta# Pasoporel meridianocentral al#1º# Año# meridiano# º)# Mes# Día# Superficie manchada Cortie# Clase# Distancia#al#en#mm2# centro#en# mm# Considering we have the areas in square mm and the areas in msh as well as the distance from the disk center in mm, it is possible to recomputed both types of areas from each other if we know the size of the Sun on the drawing in mm over time. The catalog only hints at a mean diameter of 150 mm over the set of observations, but does not give more information. We first tried with a fixed radius of 75mm but realized very rapidly that the distance from disk center was too often above this measurement. So we realized a fit with the mean radius value, and used an approximate formula 1) computing the correction for each day of the year to compute the observed variations of this radius with time over the period. correction= x sin2πdayofyear-93))/365)) 1) We chose the value that minimizes the residuals of the areas in msh from the catalog to the recomputed areas. We obtain a mean radius of : 77.2 mm. Once the areas have been recomputed in msh and in mm, we can run the first diagnostics on the catalog. To complement that, we also grouped the spots observations are very similar to single spots, even if they are not always equivalent) into groups and thus could access to typical group parameters like the extent of the group in degrees for example. This is also another tool for diagnostics. Diagnostics of pb in Aguilar catalog: Existing area mm2 / recomputed area mm2 Existing area msh / recomputed area msh Group extent: detect large values Groups extending on 2 days Figure1: Image of a page of the 1917 Madrid catalogue. The groups wrongly extend from one day to the next. After running the diagnostics, we were able to compare this catalog with other sources. This is explained in the next sections. 2/Analysis of the data in the Modern catalogue : Madrid Observatory The data from this part of the catalogue does not show individual spot information, it is only group data. Table 2 shows the content of this catalog. Table 2 shows the content of the Modern catalogue : Año# Mes Día date Nºobservación Nºdel grupo Longitud Latitud Medida Reducida Total día Nº Día millonª#de# hemisferio#

3 We compared the data here with the data form the Uccle Solar Equatorial table USET). It helps assess the overall quality of the Madrid data versus the data from USET that has been digitized and analyzed with a dedicated software DIGISUN) with operators over a few years. We can see that overall, the USET catalogue shows more entries. However, as the USET data does not include sizes of groups yet work in progress) we cannot compare the identified sizes. We plan on comparing with the partially available RGO data to show that the missed groups are the smallest. This comparison enables to point out defects in the Madrid catalogue, but also in the USET catalogue. In the example below, we see that USET shows a deficit of groups. But if we check on the drawing for that day, on the right, we can see that it says incomplete, which explains this unusual difference :03:00.00/ :15:00.00/ Figure'2:left) synoptic map of the Sun for Jan. 11 th 1980 with Madrid in black and USET in red crosses. right) Drawing from USET. With this comparison we also produced a new catalogue with the Zurich/McIntosh types of the groups in this catalogue. 3/ Comparison with other sources Different sources are available to compare the catalogues concerned by this mission, they are described in Fig. 3 and the most prominent ones were used during the mission. We will extend the comparisons/ quality assessment to other catalogues in the future. Figure' 3: Diagram of other sources of data available for comparison with the Aguilar and modern catalogue data from Madrid.

4 4/ Plans for future articles: In the context of this mission we also made advanced plans for the publication of 2 to 3 articles in the very near future. The first possible one is on new data for the butterfly diagram around the Maunder minimum, the second one is on the creation and analysis of the Aguilar Catalogue, and a third one would be realized on the creation and subsequent analysis of the more recent Madrid catalogue. 5/ Paper on Cortie classification We also were correcting a previous manuscript submitted to Solar Physics minor revisions) about the conversion of Cortie morphological classification of sunspot groups to Zurich classification Carrasco et al., 2015). We hope that it will be accepted soon. DESCRIPTIONOFTHEMAINRESULTSOBTAINED: Diagnosticsofcatalogues This STSM enabled us first to assess the quality of the data that was digitized. The first step was to detect errors, see if they are digitization errors, or errors that exist in the original files. We thus improved the quality of the catalogues before realizing any additional work. Diagnostics are described in previous sections 1/ and 2/. Comparisonwithothersources 1) Aguilar: RGO comparison: grouping spots in groups a. Diagnostics b. Create group file c. Compare with RGO d. Diagnostics of problems in the Aguilar catalog / RGO catalog Figure 4: left) Corrected areas from the RGO catalogue compared to the Aguilar areas for groups) in the data from Madrid. right) Distribution of the distance between matched groups. It is very interesting to note that the difference in areas between the Aguilar catalogue and the RGO catalogue is of about 40% Fig 4, left), which is very similar to what is found between RGO and USAF/SOON by D. Hathaway and Balmaceda et al. 2009). The distance between matched groups is relatively correct with a peak value around 1 degree. Considering I group the spots with a simple mean value of their latitudes and longitudes, this is very good.

5 This comparison will enable us to compare the Cortie classification to the local RGO classification. Indeed, comparing to the Zurich classification directly is very complicated as the RGO classes are very simple. However, the additional step represented by the Cortie classification might be just the link that we were missing before. Add to that the recent association scheme developed in Carrasco et al. 2015), and we might have a way to link the RGO classification to the more modern types. In addition, we now have a group catalogue, for which we have the spots included. This is thus a very detailed catalogue for such an early period. In addition, as can be seen from Fig. 2, we will use the Kodaikanal and Mount Wilson data for groups and spots and will be able to assess the quality of the data from RGO, Kodaikanal and Mount Wilson on this period. 2) Modern: USET comparison a. Diagnostics b. Comparison with USET catalogue c. Creation of new catalog: new file with Zurich classes and flags for errors) Figure 5: Distribution of the distance between matched groups between the Madrid catalogue and the USET catalogue. The distance between matched groups is relatively correct with a peak value slightly below 2 degrees. I d say this is mostly due to a problem of precision of the measurements in the Madrid Modern catalogue, but I d have to realize a deeper analysis to confirm this statement. For this particular catalogue, we have the possibility to add information to this very dataset. We can also use the Modern Catalogue data to assess the quality of existing datasets during the overlapping period. As mentioned earlier, although the USET dataset is the only one completely overlapping this dataset, it does not enable the comparison of the areas of the groups. However, several catalogues partially overlap this data. And, another very interesting possibility is to use this catalogue as a reference backbone to link the data from the earlier catalogues RGO, Kodaikanal, Mount Wilson) to the more recent catalogues DPD, USAF, USET), in the sense used in Balmaceda et al. 2009) to make a uniform area database. FUTURECOLLABORATIONSWITHHOSTINSTITUTION We have a collaboration for the composition of a Poster based on Carrasco et al., 2015) at the final TOSCA meeting in KIEL, and we plan on publishing articles based

6 on our collaboration from the STSM and in the future. Furthermore, it is important to note that we have started this collaboration on catalogs of sunspots and we believe that our collaboration will last a long time since we have detected a large number of catalogs that must be retrieved and analyzed Ebro observatory in Spain, Coimbra observatory in Portugal, San Miguel Observatory in Argentina, etc.) FORESEENPUBLICATIONS Four foreseen publications: 1) V.M.S. Carrasco, L. Lefèvre, J.M. Vaquero and M.C. Gallego, Equivalence relations between the Cortie and Zurich sunspot group morphological classifications, Solar Physics, in revision. 2) Improving Sunspot Records: Towards a Butterfly Diagram for the 17th Century. 3) Sunspot Catalogue of Miguel Aguilar , Madrid Observatory) 4) Sunspot Catalogue of Madrid Observatory ) REFERENCES: Aparicio, A.J.P., Vaquero, J.M., Carrasco, V.M.S., Gallego, M.C.: 2014, Solar Phys.289,4335.DOI: /s11207H014H0567Hx. Balmacedaetal.,2009,JournalofGeophysicalResearchSpacePhysics), 114,A07104 Carrasco et al., Equivalence relations between the Cortie and Zurich sunspotgroupmorphologicalclassifications,solarphysics,inrevision. Cortie,A.L.:1901,Astrophys.J.13,260.DOI: / Lefèvre, L. and Clette, F.: 2014, Solar Phys. 289, 545. DOI: /s11207H012H0184H5.