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On 25 June 2022, the third edition of Soapbox Science takes place in Brussels. Soapbox Science is a public outreach platform that was initiated in London, UK in 2011 to promote women in science, and that was spread worldwide since then. Between 2011 and 2018, 40 cities hosted the initiative in not less than 8 countries over 4 continents, and in 2020, despite the pandemic, 56 events were organized in 14 countries around the world. While the start of Soapbox Science Brussels was challenged by the COVID pandemic, a first virtual event was organised in the fall of 2020 via the YouTube and Facebook platforms [1]. Despite the difficulties related to the sanitary conditions, the first real-life edition of Soapbox Science Brussels finally took place in the heart of the Belgian capital in June 2021, following the standard format prescribed by the international Soapbox Science initiative. This event was a success, both with respect to the response of the scientific community and with regard to the interest of the public during the event. The third edition of Soapbox Science Brussels is currently in preparation, the list of selected speakers is already available and we just launched the campaign for the recruitment of volunteers. In this communication, we present the development of the Soapbox Science initiative in Belgium. We describe the motivations, challenges, issues and opportunities encountered throughout the process, and how Soapbox Science is gradually taking its place in the Belgian context for the promotion of women in sciences. Links: Facebook: https://www.facebook.com/SoapboxScienceBrussels Twitter account: @SoapboxscienceB References: [1] Pham, L. B. S., et al., Soapbox Brussels, une première en Belgique, Science connection nr. 65, August-september 2021; in French: http://www.belspo.be/belspo/organisation/publ/pub_ostc/sciencecon/65sci_fr.pdf; in Dutch: http://www.belspo.be/belspo/organisation/publ/pub_ostc/sciencecon/65sci_nl.pdf

MOMSTER (MObile Meteor STation for Education & outreach) has developed a Meteor Education Kit as a resource for STEAM (Science, Technology, Engineering, Arts, Mathematics) teachers in secondary schools. This kit includes a mobile radio meteor station consisting of a dedicated antenna and radio receiver, as well as an educational package to learn all about meteors and their impact on the atmosphere and the planet as a whole, while at the same time conveying a fascination for the ephemeral beauty and complexity of these natural light shows. The project goals are stimulating STEAM (ultimately resulting in nudging future career choices towards science or engineering career paths) and the use of citizen science (especially the Radio Meteor Zoo initiative on the online citizen science platform Zooniverse) at schools, and reaching the general public. The development of educational resources builds upon preliminary experiences we gained by participating in an Erasmus+ project called BRITEC (Bringing Research into ThE Classroom), in which teachers and pupils participated in the Radio Meteor Zoo activity. The following educational resources are available in Dutch and French on the MOMSTER website (https://momster.aeronomie.be): Geography: relationship between comets and meteors Arts: infographics & science-based art Mathematics & IT: calculation of distances using Pythagoras’ theorem and working with a spreadsheet More teaching materials are currently under development, especially about mathematics (geometry used to retrieve the meteoroid’s path) and geography (meteorites in Antarctica). How are inclusion issues taken into account? The project manager having a physical disability, we are well aware and acknowledge the challenges people with disabilities face. The developed material will be accessible for them. Moreover, the fact that the data are also made audible in real time opens up the experience and the data interpretation to people with visual disabilities. Bringing the device to the schools is, within this context, also a unique opportunity to more easily get in contact with youngsters who would otherwise get less chances to do so (children with a disability or living in underprivileged families, boys as well as girls), and the art component may attract students who initially lack STEM interests. The design of our concept implies an increased potential to reach those who are often missed. What innovative methods of science education can help to promote teaching and dissemination of science, and involve the schools? Space and atmospheric science are STEM disciplines par excellence, involving various science fields (physics, mathematics, chemistry, biology, geography, engineering, ...). As a subject triggering the imagination, the “study of shooting stars and meteor showers" has the potential to raise interest in STEM disciplines and increase science information retention by linking with art and citizen science, both in formal and informal education. We foster collaborations with teachers from secondary schools to boost interest in the science behind these phenomena.

RoadMap (ROle of and impAct of Dust and clouds in the Martian AtmosPhere: from lab to space)is a H2020 project led by a consortium of European scientific institutions which aims to improveour multidisciplinary understanding of the Martian atmosphere. The topics investigated byRoadMap will ensure that a large public will be reached and questions related to life emergence andspace exploration will be addressed. The key audiences for our project are the scientific andeducation community, the specialized public, the general public (including students) and the media;local and national geographical groups.Raising awareness about Mars, Space Exploration, Solar System and ESA activities amongteachers, students and general public is an important objective of the RoadMap Communication,Education and Public Outreach plan. We will present some of the EPO activities/tools developed inRoadMAp. Such is the case e.g. of Mars in a box an educational project aiming to introduceEuropean secondary school students to fundamental science through cutting-edge research on Mars.Mars in a box combines the classic "experiment box" format with the power of online applicationsand the excitement of accessing, visualising and managing scientific data from cutting-edge spacemissions and ground-based laboratories, as well as the possibility of contacting professionalresearchers in the field of planetary science.The RoadMap consortium is composed of the Royal Belgian Institute for Space Aeronomy(BIRA-IASB, Belgium), Aarhus University (AU, Denmark), the Duisburg & EssenUniversity (UDE, Germany), the Instituto de Cerámica y Vidrio (ICV-CSIC, Spain), and theInstituto de Astrofísica de Andalucía (IAA-CSIC, Spain) belonging to the Spanish ResearchCouncil (CSIC).

'A Touch of Space Weather' is a project that brings space weather science into the hands of blind and visually impaired high-school students. This project was awarded an EGU Public Engagement Grant in 2021. We address three challenges: There is a high demand for educational material addressing STEM topics for blind and visually impaired students (B&VI). During the covid pandemic, teachers and supporters of B&VI students required audio educational material. Tactile images that translate visual content for B&VI students are needed. The challenge is to create them so that everyone can easily reproduce them. Why space weather? This project wants to highlight the importance of space weather, as it influences nearly every aspect of our modern life ranging from banking, navigation, and telecommunications to the power supply. It is an interdisciplinary subject and, therefore, ideal for explaining complex scientific topics. All topics addressed in this project are main points in science high-school education, such as the Sun, Earth's atmosphere, Earth's magnetic field, Radiation dose, and others. The explanation of these topics is done through the 'space weather lenses' to assure that the students understand the effects of cosmic radiation, solar wind and other phenomena on the human body, technology and infrastructure. What do we develop? Audio booklets that address specific topics related to space weather while being relevant to high school education Tactile images that help blind and visually impaired students to feel visual content relevant to the audio booklets 1) Audio booklets The audio booklets will cover 12 topics: Sun Solar storm Earth's atmosphere Earth's magnetic field Radiation dose Aurora Moon exploration Space flight Mars Animal's magnetoreception After receiving feedback from a group of six educators and teaching supporters for B&VI students, we have found out high priority topics that will be prepared first. The audio booklets will be provided in three languages: Dutch French English. 2) Tactile images and 3D models Transformation of visual content into tactile content is not easy and needs plenty of tryouts. We developed nine tactile images that help to envision content from the audio booklets: The Sun Earth's atmosphere Earth's magnetic field Formation of aurora Aurora Radio communication Geomagnetically induced electrical currents Space weather effects Radiation belts All tactile images are made from easy-to-get materials from hobby shops. This way, everyone can reproduce the tactile images, not only the teacher but also family members & friends of B&VI students. We have selected 11 models for 3D printing relevant to the project's topics. These models are public, and anyone with a 3D printer can print them out. How do we share the content? We will share the content physically with Belgian schools for B&VI students and publicly online. 1) 'A Touch of Space Weather' boxes Several 'A Touch of Space Weather' boxes will be distributed to the schools and organisations providing education to B&VI people in Belgium. Each box will include one USB stick with all audio booklets, several 3D printed models and a set of tactile images. Non-B&VI students will prepare the tactile images during several workshops at regular high schools. In the first part of the workshop, non B&VI students will learn about space weather, and in the second part, they will create a set of tactile images based on our instructions. This way, students that are not blind will learn about space weather and inclusiveness. All images prepared by these students will be given to B&VI students through our boxes. 2) Website To make the materials accessible online, we will provide them publicly on our website in three languages. In addition, tutorials and downloadable templates for tactile images will help teachers and parents to create tactile images; audio booklets will be streamable and downloadable. Additional engagement To engage B&VI students from the beginning, we organised a contest searching for a jingle that will be used as an introduction to each of the audio booklets. The winning jingles will be included in all our audio booklets. In May 2022; we visited De Kade and provided two workshops for blind students. We have received their feedback on the materials we develop.

'A Touch of Space Weather' is a project that brings space weather science into the hands of blind and visually impaired (B&VI) high-school students. This project was awarded an EGU Public Engagement Grant in 2021.The goal of our project is to offer B&VI teachers a new approach to teaching complex STEM topics in a creative way. One of the main activities is the creation of audio booklets, a type of media in high demand by B&VI teachers. These audio booklets address various scientific topics that are taught in science classes in general high schools, such as the Sun, Earth's magnetic field, Moon exploration, and more.This project wants to highlight the importance of space weather, as it influences nearly every aspect of our modern life ranging from banking, navigation, telecommunications to the power supply. It is an interdisciplinary subject and therefore ideal for explaining complex scientific topics to students while at the same time teaching them space- and geo-sciences. That is why each audio booklet includes a description of a space weather phenomenon or effect relevant to the topic.3D printed models and a tactile image provide hands-on activities to complement the audio lessons. The EGU Public Engagement Grant is covering the physical costs of creating a minimum of 30 ‘A Touch of Space Weather’ boxes that will be distributed to the schools and organizations that are providing education to B&VI people. Each box will include material for one tactile image, one USB stick with all audio booklets, assignments for students, and 3D printed models to accompany audio booklets.

We are attempting to gather all information available to study the question of the representation of women in astronomy in Belgium, which is not a straightforward task. In an early study, [1] analysed gender-specific statistics on the Belgian physicists. One of the difficulties they found was that Belgium keeps different statistics for the French-speaking and Flemish universities, and the career structure is different depending on the Communities. As preliminary analysis, we investigated the percentage of women in the International Astronomical Union (IAU) registered in the database for Belgium [2]. The IAU is an international organization with participation from 68 countries that covers the main areas of astronomy, including planetary science. In 2021, 32 out of 144 Belgian members were female (22%). It is important to notice that not all astronomers in Belgium, and in particular not the younger generation where the percentage of female researchers is higher, are member of IAU. Therefore we expect these values to underestimate the true number of women in the field. In view of the fact that it is the same at the level of the funding bodies and, by construction, at the universities, Earth and Space Sciences will be considered together. We will present preliminary results of our study. References: [1] Petra Rudolf, Vice‐President, Christine Iserentant, Muriel Vander Donckt, Nathalie Balcaen, Peggy Fredrickx, Karen Janssens, and Griet Janssen, "Women in Physics in Belgium: Still a Long Way From Achieving Gender Equality", AIP Conference Proceedings 628, 131-132 (2002) https://doi.org/10.1063/1.1505297 [2] https://www.iau.org/administration/membership/individual/distribution/

In May 2020, Europlanet Society launched a call to fund projects to engage the public with planetary science. Our project proposal called MOMSTER: MObile Meteor STation for Education & outReach was amongst the three projects that were granted. MOMSTER aims at developing a Meteor Education Kit as a resource for STEAM (Science, Technology, Engineering, Arts, Mathematics) teachers in secondary schools. The kit includes a mobile radio meteor station consisting of a dedicated antenna and radio receiver, as well as an educational package to learn all about meteors and their detection methods, while at the same time conveying a fascination for the ephemeral beauty and complexity of these natural light shows. The project goals are stimulating STEAM (ultimately resulting in nudging future career choices towards science or engineering career paths) and the use of citizen science (especially the Radio Meteor Zoo initiative on the online citizen science platform Zooniverse) at schools, and reaching the general public. The development of educational resources builds upon preliminary experiences we gained by participating in an Erasmus+ project called BRITEC (Bringing Research into ThE Classroom), in which teachers and pupils participated in the Radio Meteor Zoo activity. We are presently in a pilot phase where three Belgian schools (two Dutch speaking and one French speaking) test the mobile radio meteor station and the educational resources, and give their feedback. We are using STEAM-education as an approach to broaden our target group towards less scientifically oriented students. We do this by developing an educational resource on visual (science) communication. We also organized an art & design competition for high school students with more than 30 submissions. The best piece of art will decorate the ‘MOMSTER boxes’ we use for transport of the radio receivers.

BackgroundWikipedia is an open source, web-based encyclopedia, allowing anonymous and registered users to create, edit and improve articles. A survey in 2018 showed that as many as 90% of Wikipedia's editors were male and as many as 81% of contributors were from the Global North [1]. In addition, there are fewer contributions about women, especially in STEM fields, and they are usually less developed [2]. In October 2014, only 15.53% of English Wikipedia's biographies were about women [3]. The WikiProject Women in Red was founded in July 2015 with the objective to address this gender bias in Wikipedia content. They succeeded in increasing the above-mentioned percentage to 18.71% as of 11 January 2021 [2].Today, Wikipedia is within the 20 most popular websites [4] and every month it attracts more than 1 billion unique visitors [5]. Wikipedia therefore has a huge potential to change publics perception of who is doing science and what a scientist ‘looks’ like.(Women) planetary scientists on Wikipedia?In June 2020, there were only 189 planetary scientist biographies on the English Wikipedia, including 48 biographies of female planetary scientists (25%). This percentage is in agreement with the percentage of women in the International Astronomical Union from all ESA’s Member States (24%) [6], but planetary scientists are clearly underrepresented on Wikipedia. Many of them either do not have a Wikipedia biography yet, or if they do, they are often misclassified under the category of “astronomers” or “astrophysicists”.A Planetary Sciences Edit-a-thon The Diversity Committee of the Europlanet Society aims to highlight diversity within the planetary science community. Therefore, they organised, in collaboration with Women in Red and WikiDonne, the first Planetary Science Wiki Edit-a-thon during the Europlanet Science Congress (EPSC) 2020 [7]. An Edit-a-thon (‘edit marathon’) is an organized event where editors from an online community (such as Wikipedia in this case) write, translate and improve articles on a specific topic [2]. Thirty persons received a basic editing training, resulting in 1 new article and 5 translated ones. A small subgroup still meets every month to continue the project.References[1] https://meta.wikimedia.org/wiki/Community_Insights/2018_Report[2] https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Women_in_Red [3] Eduardo Graells-Garrido, Mounia Lalmas, Filippo Menczer, "First Women, Second Sex: Gender Bias in Wikipedia", arXiv, 9 February 2015, p. 3.[4] "Wikipedia.org Traffic, Demographics and Competitors". www.alexa.com. Retrieved October 1, 2019.[5] https://stats.wikimedia.org/#/all-wikipedia-projects[6] Piccialli A., et al., Participation of women scientists in ESA Solar System missions: a historical trend, Adv. Geosci., 53, 169–182, https://doi.org/10.5194/adgeo-53-169-2020, 2020.[7] https://www.europlanet-society.org/epsc-2020-planetary-science-wiki-edit-a-thon/

Soapbox Science is quite a novel public outreach platform that was initiated in the UK in 2011 to promote women in science, and that was spread worldwide since then. Between 2011 and 2018, 40 cities hosted the initiative in not less than 8 countries over 4 continents, and in 2020, despite the pandemic, 56 events were organized in 14 countries around the world. In 2019, a small team of scientists and science communicators from two Belgian Scientific Federal Institutes decided to organise a Soapbox Science event in Belgium to promote the visibility and the role of women in science in Belgium. The first Belgian event took place in fall 2020, not in the centre of Brussels as initially planned, but as a virtual event live-streamed via YouTube and Facebook due to physical limitations imposed by the COVID-19 pandemic.We present an overview of the preparation and the conduct of this first Soapbox Science Brussels event, and describe the motivations, challenges, issues and opportunities encountered throughout the process, as well as the outcome and perspectives of Soapbox Science in Belgium.

Asteroseismology offers the possibility of probing stellar interiors and testing evolutionary and seismic models. Precise photometry and spectroscopy obtained during multi-site campaigns on young open clusters allows discovering rich samples of pulsating stars and using them in a simultaneous seismic modelling called ensemble asteroseismology. The aim of this study is to obtain the age of the open cluster NGC 6910 by means of ensemble asteroseismology of the early-type pulsating members, to derive their stellar parameters, and to classify the excited modes. We used time-series analysis, performed photometric and spectroscopic mode identification, and calculated grids of evolutionary and seismic models to apply the procedure of ensemble asteroseismology for nine pulsating members of NGC 6910. With two iterations of the procedure of ensemble asteroseismology applied to nine pulsating stars we derived an age of 10.6$^{+0.9}_{-0.8}$ Myr for NGC 6910. Of the nine pulsating stars examined in the paper, eight are $\beta$ Cep stars, including three that are hybrid $\beta$ Cep and slowly pulsating B-type (SPB) pulsators, and one is an SPB star. Interestingly, the least massive $\beta$ Cep star, NGC 6910-38, has a mass of about 5.6 M$_\odot$. The present theory does not predict unstable $p$ modes in B-type stars with such a low mass. The $g$ modes with relatively high frequencies ($>3.5$ d$^{-1}$), observed in three members of the cluster, are also stable according to seismic modelling. Both findings pose a challenge for theoretical calculations and prompt a revision of the opacities. The procedure of ensemble asteroseismology was found to be successful for NGC 6910 and $\chi$ Per on the basis of pulsating B-type stars and can therefore be applied to other young open clusters that are rich in such stars., Comment: 22 pages, 24 figures. Caution: arXiv abstract is shorter than in the article

We used extensive ground-based multisite and archival spectroscopy to derive observational constraints for a seismic modelling of the magnetic beta Cep star V2052 Ophiuchi. The line-profile variability is dominated by a radial mode (f_1=7.14846 d^{-1}) and by rotational modulation (P_rot=3.638833 d). Two non-radial low-amplitude modes (f_2=7.75603 d^{-1} and f_3=6.82308 d^{-1}) are also detected. The four periodicities that we found are the same as the ones discovered from a companion multisite photometric campaign (Handler et al. 2012) and known in the literature. Using the photometric constraints on the degrees l of the pulsation modes, we show that both f_2 and f_3 are prograde modes with (l,m)=(4,2) or (4,3). These results allowed us to deduce ranges for the mass (M \in [8.2,9.6] M_o) and central hydrogen abundance (X_c \in [0.25,0.32]) of V2052 Oph, to identify the radial orders n_1=1, n_2=-3 and n_3=-2, and to derive an equatorial rotation velocity v_eq \in [71,75] km s^{-1}. The model parameters are in full agreement with the effective temperature and surface gravity deduced from spectroscopy. Only models with no or mild core overshooting (alpha_ov \in [0,0.15] local pressure scale heights) can account for the observed properties. Such a low overshooting is opposite to our previous modelling results for the non-magnetic beta Cep star theta Oph having very similar parameters, except for a slower surface rotation rate. We discuss whether this result can be explained by the presence of a magnetic field in V2052 Oph that inhibits mixing in its interior.

While the first binary post-AGB stars were serendipitously discovered, the distinct characteristics of their Spectral Energy Distribution (SED) allowed us to launch a more systematic search for binaries. We selected post-AGB objects which show a broad dust excess often starting already at H or K, pointing to the presence of a gravitationally bound dusty disc in the system. We started a very extensive multi-wavelength study of those systems and here we report on our radial velocity and photometric monitoring results for six stars of early F type, which are pulsators of small amplitude. To determine the radial velocity of low signal-to-noise time-series, we constructed dedicated auto-correlation masks. The radial velocity variations were subjected to detailed analysis to differentiate between pulsational variability and variability due to orbital motion. Finally orbital minimalisation was performed to constrain the orbital elements. All of the six objects are binaries, with orbital periods ranging from 120 to 1800 days. Five systems have non-circular orbits. The mass functions range from 0.004 to 0.57 solar mass and the companions are likely unevolved objects of (very) low initial mass. We argue that these binaries must have been subject to severe binary interaction when the primary was a cool supergiant. Although the origin of the circumstellar disc is not well understood, the disc is generally believed to be formed during this strong interaction phase. The eccentric orbits of these highly evolved objects remain poorly understood. With the measured orbits and mass functions we conclude that the circumbinary discs seem to have a major impact on the evolution of a significant fraction of binary systems., 13 pages, 15 figures, accepted for Astronomy and Astrophysics

The known beta Cephei star HD 180642 was observed by the CoRoT satellite in 2007. From the very high-precision light curve, its pulsation frequency spectrum could be derived for the first time (Degroote and collaborators). In this paper, we obtain additional constraints for forthcoming asteroseismic modeling of the target. Our results are based on both extensive ground-based multicolour photometry and high-resolution spectroscopy. We determine T_eff = 24 500+-1000 K and log g = 3.45+-0.15 dex from spectroscopy. The derived chemical abundances are consistent with those for B stars in the solar neighbourhood, except for a mild nitrogen excess. A metallicity Z = 0.0099+-0.0016 is obtained. Three modes are detected in photometry. The degree l is unambiguously identified for two of them: l = 0 and l = 3 for the frequencies 5.48694 1/d and 0.30818 1/d, respectively. The radial mode is non-linear and highly dominant with an amplitude in the U-filter about 15 times larger than the strongest of the other modes. For the third frequency of 7.36673 1/d found in photometry, two possibilities remain: l = 0 or 3. In the radial velocities, the dominant radial mode presents a so-called stillstand but no clear evidence of the existence of shocks is observed. Four low-amplitude modes are found in spectroscopy and one of them, with frequency 8.4079 1/d, is identified as (l,m)=(3,2). Based on this mode identification, we finally deduce an equatorial rotational velocity of 38+-15 km/s., Accepted for publication in Astronomy and Astrophysics

Gamma Doradus stars are excellent targets for asteroseismology since the gravity modes present in these stars probe the deep stellar interiors. Mode identification will improve the knowledge of these stars considerably. A selected group of Gamma Doradus stars and some candidates were observed with the Mercator telescope to find and/or confirm the periodicities in the light variations and to derive reliable amplitude ratios in different pass bands. A frequency analysis was performed on all new data obtained in the Geneva photometric system. In order to have more reliable and accurate frequencies, the new data were combined with similar data from the literature and with Hipparcos observations. A set of frequencies that minimized the the residuals in a harmonic fit was searched for while allowing means and amplitudes to vary from one observation set to another. Frequencies and amplitudes in the photometric passbands of the Geneva system are given for 21 Gamma Doradus stars. We report the discovery of HD 74504 as a newly found Gamma Doradus star. Our study provides the first extensive multicolour database for the understanding of gravity modes in F-type stars., Comment: Electronic tables (5 to 25) not included in this version

We analyse the complex short-term Si  line-profile variability of the spectroscopic binary β Cep star κ Sco after orbit subtraction, before and after spectral disentangling. We refine the known oscillation frequency of the star: f1 = 4.99922 c d −1 and detect 2 f1. Variability is also found at frequencies near f2 � 4.85 c d −1 and f3 � 5.69 c d −1 or their aliases. These frequencies are not significant if we consider the spectra alone, but they survive our selection after the consideration that they were derived previously from independent ground-based and space photometry by different teams. Moreover, we find dominant variability in the equivalent width with a frequency in the interval (0.22, 0.30) c d −1 which we interpret as the rotational frequency frot of the star. The complex window function does not allow us to determine definite values for f2, f3, frot. The variability with f1 is interpreted as a prograde non-radial oscillation mode with spherical wavenumbers (�, m) = (2, −1) or (1, −1). The additional frequencies are explained in terms of rotational modulation superposed to the main oscillation. We also point out that we cannot disprove the variability in κ Sco to originate from co-rotating structures. KOREL disentangling preserves the large-amplitude line-profile variability but its performance for complex low-amplitude variability remains to be studied in detail.

We derive accurate values of the orbital parameters of the close binary β Cephei star λ Scorpii. Moreover, we present the first determination of the properties of the triple system to which λ Scorpii belongs. Our analysis is based on a time series of 815 high-resolution spectra, covering a timespan of 14 years. We find a close orbit of 5. 9525 days (e = 0.26) and a wide orbit of approximately 1082 d days (e = 0.23). The orbital parameters of the triple star and a spectrum synthesis lead us to conclude that the system is composed of two early-type B stars and a low-mass pre-main-sequence star rather than containing an ultra- massive white dwarf as claimed before. Our proposed configuration is compatible with population synthesis. The radial velocity variations of the primary allow us to confirm the presence of at least one pulsation mode with frequency 4.679410 c d −1 which is subject to the light-time effect in the triple system. A detailed analysis of the complex line-profile variations is described in a subsequent paper.

Asteroseismology of the β Cephei star ν Eridani : III. Extended frequency analysis and mode identification

An eight-year long reanalysis of atmospheric composition data covering the period 2003-2010 was constructed as part of the FP7-funded Monitoring Atmospheric Composition and Climate project by assimilating satellite data into a global model and data assimilation system. This reanalysis provides fields of chemically reactive gases, namely carbon monoxide, ozone, nitrogen oxides, and formaldehyde, as well as aerosols and greenhouse gases globally at a horizontal resolution of about 80 km for both the troposphere and the stratosphere. This paper describes the assimilation system for the reactive gases and presents validation results for the reactive gas analysis fields to document the data set and to give a first indication of its quality. Tropospheric CO values from the MACC reanalysis are on average 10-20% lower than routine observations from commercial aircrafts over airports through most of the troposphere, and have larger negative biases in the boundary layer at urban sites affected by air pollution, possibly due to an underestimation of CO or precursor emissions. Stratospheric ozone fields from the MACC reanalysis agree with ozonesondes and ACE-FTS data to within ±10% in most seasons and regions. In the troposphere the reanalysis shows biases of -5% to +10% with respect to ozonesondes and aircraft data in the extratropics, but has larger negative biases in the tropics. Area-averaged total column ozone agrees with ozone fields from a multi-sensor reanalysis data set to within a few percent. NO2 fields from the reanalysis show the right seasonality over polluted urban areas of the NH and over tropical biomass burning areas, but underestimate wintertime NO2 maxima over anthropogenic pollution regions and overestimate NO2 in northern and southern Africa during the tropical biomass burning seasons. Tropospheric HCHO is well simulated in the MACC reanalysis even though no satellite data are assimilated. It shows good agreement with independent SCIAMACHY retrievals over regions dominated by biogenic emissions with some anthropogenic input, such as the eastern US and China, and also over African regions influenced by biogenic sources and biomass burning. © Author(s) 2013., SCOPUS: re.j, info:eu-repo/semantics/published

We aim to interpret the photometric and spectroscopic variability of the luminous blue variable supergiant HD\,50064 ($V=8.21$).CoRoT space photometry and follow-up high-resolution spectroscopy, with a time base of 137\,d and 169\,d, respectively, was gathered, analysed and interpreted using standard time series analysis and light curve modelling methods as well as spectral line diagnostics.The space photometry reveals one period of 37\,d, which undergoes a sudden amplitude change with a factor 1.6. The pulsation period is confirmed in the spectroscopy, which additionally reveals metal line radial velocity values differing by $\sim 30\,$km\,s$^{-1}$ depending on the spectral line and on the epoch. We estimate \teff$\sim$13\,500\,K, \logg$\sim$1.5 from the equivalent width of Si lines. The Balmer lines reveal that the star undergoes episodes of changing mass loss on a time scale similar to the changes in the photometric and spectroscopic variability, with an average value of $\log\dot{\rm M}\simeq-5$ (in M$_\odot$\,yr$^{-1}$). We tentatively interpret the 37\,d period as due to a strange mode oscillation., Comment: 4 pages, accepted for publication in Astronomy & Astrophysics Letters

International audience; Context: We present the CoRoT light curve of the beta Cep star HD 180642, assembled during the first long run of the space mission, as well as archival single-band photometry. Aims: Our goal is to analyse the detailed behaviour present in the light curve and interpret it in terms of excited-mode frequencies. Methods: After describing the noise properties in detail, we use various time series analyses and fitting techniques to model the CoRoT light curve, for various physical assumptions. We apply statistical goodness-of-fit criteria that allow us to select the most appropriate physical model fit to the data. Results: We conclude that the light-curve model based on nonlinear resonant frequency and phase locking provides the best representation of the data. Interpretation of the residuals is dependent on the chosen physical model used to prewhiten the data. Conclusions: Our observational results constitute a fruitful starting point for detailed seismic stellar modelling of this large-amplitude and evolved beta Cep star.

The β Cephei star HD 180642 was observed by the CoRoT satellite during a run of 156 days in 2007. The space white light photometry revealed the rich frequency spectrum of the star (Degroote et al. 2009). In the present study, we provide additional information on the target, based on both ground‐based multi‐colour photometry and high‐resolution spectroscopy. We place our object in the (Teff, log g) diagram. In addition, we derive the chemical abundances of several elements as well as the metallicity of HD 180642. Finally, we put constraints on the identification of some modes. All these observational constraints will be used to compute stellar models of the target.

We present time-series radial-velocity and photometric observations of a solar-type double-lined eclipsing binary star (V12) near the turnoff in the old open cluster NGC188. We use these data to determine the spectroscopic orbit and the photometric elements for V12. From our analysis we determine accurate masses (Mp=1.103+-0.007Msun, Ms=1.081+-0.007Msun) and radii (R =1.424+-0.019Rsun, Rs=1.373+-0.019Rsun) for the primary (p) and secondary (s) binary components. We adopt a reddening of E_(B-V)=0.087 for NGC188, and derive component effective temperatures of 5900+-100K and 5875+-100K, respectively, for the primary and secondary stars. From their absolute dimensions, the two components of V12 yield identical distance moduli of Vo-MV=11.24+-0.09, corresponding to 1770+-75pc. We determine an age of 6.2+-0.2Gyr for V12 and NGC188, from a comparison with theoretical isochrones in the mass-radius diagram. This age is independent of distance, reddening, and color-temperature transformations. We use isochrones from Victoria-Regina (VRSS) and Yonsei-Yale (Y2) with [Fe/H]=-0.1 and [Fe/H]=0.0. From the solar metallicity isochrones, an age of 6.4Gyr provides the best fit to the binary components for both sets of models. For the isochrones with [Fe/H]=-0.1, ages of 6.0Gyr and 5.9Gyr provide the best fits for the VRSS and Y2 models, respectively. We use the distance and age estimates for V12, together with best estimates for the metallicity and reddening of NGC188, to investigate the locations of the corresponding VRSS and Y2 isochrones relative to cluster members in the color-magnitude diagram. Plausible changes in model metallicity and distance to better match the isochrones to the cluster sequences, result in a range of ages for NGC188 that is more than 3 times that resulting from our analysis of V12., Comment: 36 pages, 10 figures (1 color), 9 tables

The line profile variability and photometric variability of the O9.5 Vp star HD93521 are examined in order to establish the properties of the non-radial pulsations in this star. Fourier techniques are used to characterize the modulations of the He I 5876, 6678 and H-alpha lines in several spectroscopic time series and to search for variations in a photometric time series. Our spectroscopic data confirm the existence of two periods of 1.75 and 2.89 hr. The line profiles, especially those affected by emission wings, exhibit also modulations on longer time scales, but these are epoch-dependent and change from line to line. Unlike previous claims, we find no unambiguous signature of the rotational period in our data, nor of a third pulsation period (corresponding to a frequency of 2.66 day$^{-1}$). HD 93521 very likely exhibits non-radial pulsations with periods of 1.75 and 2.89 hr with $l \simeq 8 \pm 1$ and $l \simeq 4 \pm 1$ respectively. No significant signal is found in the first harmonics of these two periods. The 2.89 hr mode is seen at all epochs and in all lines investigated, while the visibility of the 1.75 hr mode is clearly epoch dependent. Whilst light variations are detected, their connection to these periodicities is not straightforward., 13 pages, 11 figures, accepted for publication in Astronomy & Astrophysics

Contains fulltext : 34555.pdf (Publisher’s version ) (Open Access) Aims. We selected a large sample of O-B stars that were considered as (candidate) slowly pulsating B, beta Cep, and Maia stars after the analysis of their hipparcos data. We analysed our new seven passband geneva data collected for these stars during the first three years of scientific operations of the mercator telescope. We performed a frequency analysis for 28 targets with more than 50 high-quality measurements to improve their variability classification. For the pulsating stars, we tried both to identify the modes and to search for rotationally split modes. Methods: We searched for frequencies in all the geneva passbands and colours by using two independent frequency analysis methods and we applied a 3.6 S/N-level criterion to locate the significant peaks in the periodograms. The modes were identified by applying the method of photometric amplitudes for which we calculated a large, homogeneous grid of equilibrium models to perform a pulsational stability analysis. When both the radius and the projected rotational velocity of an object are known, we determined a lower limit for the rotation frequency to estimate the expected frequency spacings in rotationally split pulsation modes. Results: We detected 61 frequencies, among which 33 are new. We classified 21 objects as pulsating variables (7 new confirmed pulsating stars, including 2 hybrid beta Cep/SPB stars), 6 as non-pulsating variables (binaries or spotted stars), and 1 as photometrically constant. All the Maia candidates were reclassified into other variability classes. We performed mode identification for the pulsating variables for the first time. The most probable l value is 0, 1, 2, and 4 for 1, 31, 9, and 5 modes, respectively, including only 4 unambiguous identifications. For 7 stars we cannot rule out that some of the observed frequencies belong to the same rotationally split mode. For 4 targets we may begin to resolve close frequency multiplets. Based on observations collected with the p7 photometer attached to the Flemish 1.2-m mercator telescope situated at the Roque de los Muchachos observatory on La Palma (Spain). Section [see full text], including Figs. is only available in electronic form at http://www.aanda.org, and Tables 2 and 3 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/463/243

We announce the discovery of eight new β Cephei stars and several other interesting variable stars as the preliminary result of the ongoing campaign on two northern open clusters, NGC 6910 and χ Persei.

We present methodology to derive high-precision estimates of the fundamental parameters of double-lined spectroscopic binaries. We apply the methods to the case study of the double-lined beta Cephei star beta Centauri. We also present a detailed analysis of beta Centauri's line-profile variations caused by its oscillations. We point out that a systematic error in the orbital amplitudes, and any quantities derived from them, occurs if the radial velocities of blended component lines are computed without spectral disentangling. This technique is an essential ingredient in the derivation of the physical parameters if the goal is to obtain a precision of only a few percent. We have devised iteration schemes to obtain the orbital elements for systems whose lines are blended throughout the orbital cycle. We find the following parameters for beta Cen: $M_1=10.7\pm 0.1 M_\odot$ and $M_2=10.3\pm 0.1 M_\odot$, an age of $(14.1\pm 0.6)\times 10^6$ years. We deduce two oscillation frequencies for the broad-lined primary of beta Centauri with degrees higher than 2. We propose that our iteration schemes be used in any future derivations of the spectroscopic orbital parameters of double-lined binaries with blended component lines to which disentangling can be successfully applied., Comment: 12 pages, 13 figures, accepted for publication in A&A

We have studied a sample of 28 periodically variable B-type supergiants selected from the HIPPARCOS mission and 12 comparison stars covering the whole B-type spectral range. Our goal is to test if their variability is compatible with opacity-driven non-radial oscillations. We have used the NLTE atmosphere code FASTWIND to derive the atmospheric and wind parameters of the complete sample through line profile fitting. We applied the method to selected H, He and Si line profiles, measured with the high resolution CES spectrograph attached to the ESO CAT telescope in La Silla, Chile. From the location of the stars in the (log Teff, log g) diagram, we suggest that variability of our sample supergiants is indeed due to the gravity modes resulting from the opacity mechanism. We find nine of the comparison stars to be periodically variable as well, and suggest them to be new alpha Cyg variables. We find marginal evidence of a correlation between the amplitude of the photometric variability and the wind density. We investigate the Wind Momentum Luminosity Relation for the whole range of B spectral type supergiants, and find that the later types (> B5) perfectly follow the relation for A supergiants. Additionally, we provide a new spectral type - Teff calibration for B supergiants. Our results imply the possibility to probe internal structure models of massive stars of spectral type B through seismic tuning of gravity modes., 33 pages (including 14 pages online material). Accepted for publication in Astronomy & Astrophysics

Gamma ray bursts (GRBs) are the most energetic eruptions known in the Universe. Instruments such as Compton-GRO/BATSE and the GRB monitor on BeppoSAX have detected more than 2700 GRBs and, although observational confirmation is still required, it is now generally accepted that many of these bursts are associated with the collapse of rapidly spinning massive stars to form black holes. Consequently, since first generation stars are expected to be very massive, GRBs are likely to have occurred in significant numbers at early epochs. X-red is a space mission concept designed to detect these extremely high redshifted GRBs, in order to probe the nature of the first generation of stars and hence the time of reionisation of the early Universe. We demonstrate that the gamma and x-ray luminosities of typical GRBs render them detectable up to extremely high redshifts (z~10-30), but that current missions such as HETE2 and SWIFT operate outside the observational range for detection of high redshift GRB afterglows. Therefore, to redress this, we present a complete mission design from the science case to the mission architecture and payload, the latter comprising three instruments, namely wide field x-ray cameras to detect high redshift gamma-rays, an x-ray focussing telescope to determine accurate coordinates and extract spectra, and an infrared spectrograph to observe the high redshift optical afterglow. The mission is expected to detect and identify for the first time GRBs with z > 10, thereby providing constraints on properties of the first generation of stars and the history of the early Universe., 14 pages, 10 figures, spie.cls needed

We present the results of a detailed analysis of 121 ground-based high-resolution high S/N spectroscopic measurements spread over 3 years for the Beta Cephei star Theta Ophiuchi. We discovered Theta Oph to be a triple system. In addition to the already known Speckle B5 companion of the B2 primary, we showed the presence of a low-mass spectroscopic companion and we derived an orbital period of 56.71 days with an eccentricity of 0.1670. After removing the orbit we determined two frequencies for the primary in the residual radial velocities: f1 = 7.1160 c/d and f2 = 7.4676 c/d. We also found the presence of f3 = 7.3696 c/d by means of a two dimensional frequency search across the Si III 4567 A profiles. We identified the m-value of the main mode with frequency f1 by taking into account the photometric identifications of the degrees l. By means of the moment method and the amplitude and phase variations across the line profile, we derived (l1,m1) = (2,-1). This result allows us to fix the mode identifications of the whole quintuplet for which three components were detected in photometry. This is of particular use for our forthcoming seismic modelling of the primary. We also determined stellar parameters of the primary by non-local thermodynamic equilibrium hydrogen, helium and silicon line profile fitting and we obtained Teff = 24000 K and log g = 4.1, which is consistent with photometrically determined values., 8 pages, 6 figures

Recent space observations with CoRoT and ground-based spectroscopy have shown the presence of different types of pulsations in OB stars. These oscillations could be due to acoustic and gravity modes, solar-like oscillations or even other pulsations of large growth rates. We present a first attempt at interpreting the latter as strange modes.

To optimise the science results of the asteroseismic part of the CoRoT satellite mission a complementary simultaneous ground-based observational campaign is organised for selected CoRoT targets. The observations include both high-resolution spectroscopic and multi-colour photometric data. We present the preliminary results of the analysis of the ground-based observations of three targets. A line-profile analysis of 216 high-resolution FEROS spectra of the delta Sct star HD 50844 reveals more than ten pulsation frequencies in the frequency range 5-18 c/d, including possibly one radial fundamental mode (6.92 c/d). Based on more than 600 multi-colour photometric datapoints of the beta Cep star HD180642, spanning about three years and obtained with different telescopes and different instruments, we confirm the presence of a dominant radial mode nu1=5.48695 c/d, and detect also its first two harmonics. We find evidence for a second mode nu2=0.3017 c/d, possibly a g-mode, and indications for two more frequencies in the 7-8 c/d domain. From Stromgren photometry we find evidence for the hybrid delta Sct/gamma Dor character of the F0 star HD 44195, as frequencies near 3 c/d and 21 c/d are detected simultaneously in the different filters., 7 pages, 6 figures, HELAS II International Conference "Helioseismology, Asteroseismology and MHD Connections", 2008, J.Phys.: Conf. Ser. 118, 012077

We aim to determine the fundamental parameters of a sample of B stars with apparent visual magnitudes below 8 in the field-of-view of the CoRoT space mission, from high-resolution spectroscopy. We developed an automatic procedure for the spectroscopic analysis of B-type stars with winds, based on an extensive grid of FASTWIND model atmospheres. We use the equivalent widths and/or the line profile shapes of continuum normalized hydrogen, helium and silicon line profiles to determine the fundamental properties of these stars in an automated way. After thorough tests, both on synthetic datasets and on very high-quality, high-resolution spectra of B stars for which we already had accurate values of their physical properties from alternative analyses, we applied our method to 66 B-type stars contained in the ground-based archive of the CoRoT space mission. We discuss the statistical properties of the sample and compare them with those predicted by evolutionary models of B stars. Our spectroscopic results provide a valuable starting point for any future seismic modelling of the stars, should they be observed by CoRoT., 31 pages (including 14 pages online material), 32 figures