Astronomical News

possibility of making queries in a In the afternoon, participants were able future workshops were also received, ­programmatic way. Lodovico Coccato to interact with ESO staff and discuss with opinions differing, depending on the gave a demonstration of how to reduce topics of their choice, including help with previous experience and knowledge of data with EsoReflex, as well as how to data reduction, help with proposal writing, participants. It is our aim to repeat this use the software Molecfit to remove finding information on ESO web pages, workshop approximately every two years atmospheric signatures from science installing ESO software, help with obser- to promptly address questions from the spectra. Finally, John Pritchard showed vation preparations, and using the Science continuous flow of new users of ESO how to modify Eso­Reflex workflows to Archive either to access data or to return facilities. tailor them to the user’s aims. reduced data to the archive. At registra- tion, participants were asked to indicate One full day of the workshop was dedi- the area of the programme (proposal Acknowledgements cated to hands-on sessions. In the first preparation, observing strategies and We would like to thank Véronique Ziegler for her help part, on Wednesday morning, three tools usage, data reduction) they would with the practical organisation, Stuart Ryder from ­parallel tutorial sessions were held, during like to explore further. Participants were the International Telescopes Support Office (ITSO) which participants were guided in using then split into small groups with overlap- for setting up the remote participation via Zoom, and EsoReflex for three instruments, MUSE, ping interests, or had scheduled one-to- Sandor Horvath and the Information Technology (IT) staff for their help during the workshop. We most the Ultraviolet and Visual Echelle Spectro- one sessions with the ESO staff member warmly thank all speakers and tutors for the great graph (UVES) and X-shooter. These who was best placed to help with their effort they made to provide clear and instructive instruments were chosen as the majority specific topic. talks or demonstrations and to efficiently help the of the participants expressed an interest participants in individual sessions. in them when registering for the work- At the end of the workshop, the organisers shop. In each case, after a first step-by- asked participants to provide feedback, Links step demonstration, the participants and an extremely large number of people, 1 could choose to reduce a set of data more than 50% of the attendees, did so. All presentations as well as some of the video recordings are available on the workshop web ­provided by the organisers or to work on The feedback was unanimously positive page: https://www.eso.org/sci/meetings/2018/ their own data. Two or three tutors were with all respondents saying they would Users-Workshop/program.html available for each session, helping and recommend such a workshop to their advising the participants in this endeavour. colleagues. A few suggestions for similar

DOI: 10.18727/0722-6691/5084 Report on the ESO–NEON Observing School at La Silla

held at ESO Vitacura, Santiago & La Silla Observatory in , 18 February–2 March 2018

Fernando Selman 1 During the two weeks between 19 Feb- scientific community at Vitacura. In Claudio Melo 1 ruary and 2 March 2018, the Office addition to learning about the observing Giacomo Beccari 1 for Science at Vitacura and the La Silla techniques that were used during Henri M. J. Boffin 1 Observatory were the hosts of the the school, the students also attended Valentin Ivanov 1 ­second ESO/NEON (Network of Euro- several lectures covering the current Eleonora Sani 1 pean in the North) La Silla and future capabilities of the Atacama Linda Schmidtobreick 1 Observing School. Thanks to the Large Millimeter/submillimeter Array Michel Dennefeld 2 ­generous funding from ESO, the Optical (ALMA), the telescopes at Paranal, and Heidi Korhonen 3 Infrared Coordination Network for the Extremely Large Telescope (ELT), (OPTICON), and the La Silla as well as talks on what makes a good Observatory, a group of 20 students, scientific presentation, time manage- 1 ESO consisting of mostly PhD but also some ment, effective proposal writing, and 2 Institut d’Astrophysique de Paris (IAP), advanced MSc students, from different career choices. France parts of the world, were guided by five 3 Dark Cosmology Centre, Niels Bohr ESO tutors. The students prepared Institute, University of Copenhagen, and carried out complex observations, Over the course of three nights at La Silla, Denmark reduced and analysed the data, and the students used the ESO Faint Object finally presented the results to the ESO Spectrograph and Camera (EFOSC2) and

46 The Messenger 172 – June 2018 Figure 1. Left: The ­articipants, organisers, and tutors in front of the NTT telescope. Right: Giacomo Beccari´s group in front of their target.

the infrared spectrograph and imaging Giacomo Beccari guided a group study- nature of the accretors in the observed camera SOFI attached to the New Tech- ing Ha-excess sources in the Orion objects spectroscopically. Similarly, nology Telescope (NTT) as well as the ­nebula and in Chamaeleon. In particular, DFOSC was used to perform broad-band Danish telescope, equipped with the the students acquired low-resolution V, R, I and narrow-band Ha imaging of Danish Faint Object Spectrograph and spectra with EFOSC2 to study the equiva- young stars in Chamaeleon. The images, Camera (DFOSC). Divided into five lent width of the Ha emission line of targeting a number of T Tauri stars with groups, the students worked on a variety 12 young T Tauri stars in Orion. Such Ha emission studied by the Gaia–ESO of astrophysical topics, supported by emission in young stars is typically used Heidi Korhonen at the Danish telescope, to identify ongoing accretion from a Figure 2. Students getting real-life experience at the and by Monica Castillo and Ariel Sanchez protoplanetary disc. The measurements consoles of the NTT (left), and the ­Danish telescope at the NTT 1. allowed the students to confirm the (right).

The Messenger 172 – June 2018 47 Astronomical News Selman F. et al., Report on the “ESO–NEON Observing School at La Silla Observatory”

S1 S2

0.2 )

0.0 3839

S( pec. δ

–0.2

–0.1 0.0 0.1 δG4300

Figure 4. Distribution of CN and CH differential indi- ces for Red-Giant Branch (RGB) stars of the globular cluster NGC 3201 determined by Bruno Dias’s group in the 2016 school. Three groups are identified: the main, well-populated sequence 1 (S1); a second, less populated sequence 2 (S2); and a group of CN-weak/ CH-weak peculiar stars (pec). Mean error bars are displayed in the top right corner. The dashed line was fitted to S1 stars and shifted by 1 magnitude in CH Figure 3. An interesting part of the school is the also monitored the behaviour of the binary to match the S2 and pec stars (Dias et al., 2018). scheduling of the different programmes that com- brown dwarf LUH 16AB over one night. pete for observing slots. Here the groups are trying to coordinate their observations in the La Silla School “War Room”. Eleonora Sani’s group used SOFI to targets was obtained with EFOSC2. Two obtain the spectra of two quasars falling of these objects were classified as in the redshift range 2.5–3.5, i.e., at the Type I a and the third one as survey 2, were used to confirm their peak of activity of cosmic active galactic a galactic nova. The students contributed nature photometrically (i.e., whether or nuclei. The rest-frame optical emission, to writing the corresponding astronomer’s not they are accretors). redshifted into the H- and K-bands, was telegrams. These observations, together observed by means of low-resolution with a specific lecture about the “transient Henri Boffin led a group studying plane- spectra. While the observation of the sky”, aimed to draw the attention of the tary nebulae, using both EFOSC2 and nearer quasar was affected by technical participants to this increasingly important DFOSC to discover the binary stars that problems, the quality of the data for topic, given the development of gravita- lurk at the centre of these majestic and the z ~ 3.5 source allowed the complex tional wave and neutrino detectors and colourful cosmic bubbles. The students profile of the emission lines to be decom- the future arrival of the Large Synoptic were able to obtain the radial velocity posed into narrow and broad compo- Survey Telescope (LSST) in the southern curve and the BVRI photometric light nents. The students were therefore able hemisphere. curves of the binary star inside the plane- to spot the signature of the broad-line tary nebula DS1, and use these to deter- region and to measure its size and the An interesting aspect of these observing mine the parameters of the binary. They gas velocity dispersion, allowing them to schools is that they can lead to publi­ also tried to uncover new binaries in make an estimate of the mass of the cations, even though this is not a require- some other planetary nebulae, providing supermassive black hole of 2–3 108 solar ment. Bruno Dias was a tutor at the useful upper limits as well as impressive masses. school in 2016, and led a group which colour images showing the intricate carried out multi-object spectroscopy ­morphology of these objects. They finally Linda Schmidtobreick’s group worked on using EFOSC2 to study abundances in derived the abundances in one of the the spectral classification of globular clusters. He recently published a planetary nebulae. candidates; low-resolution optical spectra paper with his students entitled “Galactic of the candidates were obtained with or extragalactic chemical tagging for Valentin Ivanov’s group followed the EFOSC2 and cross-correlated with cata- NGC3201? Discovery of an anomalous ­transit of two : WASP-43b with logue spectra to obtain the spectral types CN-CH relation” (Dias et al., 2018). Bruno SOFI, and WASP-19b with DFOSC. The of the objects. Together with externally describes the work as follows: data were processed and both transits provided light curves, the variability type were successfully detected. Light curves of each object was discussed. “Globular clusters (GCs) are known to were fitted with publicly available transit host stars with different light-element analysis tools and various parameters of In addition to the above projects, low-­ chemical abundances, such as C, N, O, the planets were measured. The students resolution spectroscopy of three transient Na, Al. In particular, the distributions of

48 The Messenger 172 – June 2018 Figure 5. The students at the school, waiting for a green flash at the end of the first day.

C-N, Na-O are anti-correlated in typical “I want to thank the organisers and Acknowledments GCs. A few anomalous clusters present tutors of the summer school. Both the We would like to express our gratitude to ESO’s multiple sequences of CN-CH anti-­ talks and the research projects were Director General, the La Silla correlation, a proxy for C-N. These spe- ­tremendously interesting, and I am sure (LPO) Director and the Director for Science, without cial GCs also share a few other odd they will be very useful in the future. I also whose unconditional support this school would not ­characteristics; this is often interpreted as want to mention what was said among have materialised. We would also like to thank the invited speakers at the school: Michele Cirasuolo, these GCs having originated in dwarf the students, that despite the level of Alain Gilliote, Pascale Hibon, Yara Jaffe, Bruno ­galaxies that were captured and destroyed stress generated, the school exceeded ­Leibundgut, Adele Plunkett, Alain Smette and by the Milky Way. Our results show that the expectations. This type of school Frédéric Vogt. Hans Zinnecker was a special con­ NGC 3201 presents multiple sequences is extremely useful for any astronomer tributor to the school, first with a lecture on star ­formation, and second, contributing to lively dis­ of CN-CH, however it does not show regardless of the area chosen in the cussions and debates about the different topics other anomalous characteristics. We have future. All the activities, from the talks to ­covered — heartfelt thanks to him! The logistical therefore discovered the first GC that is the visit to the observatory motivate aspects of the school were handled by Paulina Jirón neither completely typical nor completely us even more than we already are to con- and María Eugenia Gomez, to whom we extend our deep gratitude. anomalous, which means that the extra- tinue doing research in our PhD.” galactic origin scenario needs revision, and likely requires new stellar evolution It was intense and exhausting but we all References models that can better explain how the feel that the process was well worth the Dias, B. et al. 2018, arXiv:1803.05124 CN-CH anti-correlation forms.” effort. With this and the previous version of the school we have reached a total of The spirit of the school was accurately 40 students who are now familiar with Links summarised by an email from one of the the way ESO does astronomy at the 1 ESO–NEON Observing School: https://www.eso. students at the school, Gabriela Navarro observatories in Chile. More importantly, org/sci/meetings/2018/lasilla_school2018.html from Universidad Andrés Bello (UNAB) in we have been able to share our passion 2 Gaia–ESO Survey: https://www.gaia-eso.eu/ Santiago: and, hopefully, helped the next genera- tion of astronomers.

The Messenger 172 – June 2018 49