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The last day at Valparaiso

I think it had everything:

– waking up early to go to the bank,
– then go to the university and finalize some aspects of my talk (as a final contribution),
– go for lunch with the whole group,
– return to the university,
– to say goodbye to people,
– do the presentation,
– materialize a long-postponed discussion,
– show/discuss a script,
– buy some small gifts on the way home,
– where I just dropped my things,
– to go to an outreach talk (in spanish),
– to continue for the last drinks with all the friends from the university,
– say farewell to all,
– return home to take a shower
– and rest a bit,
– to finally think of today
– and write this post.

Definitely not the most typical day, but it isn’t after all. It is strange as I remember my first days in Valpo, almost 9 months before. It was short but nevertheless a very full experience and I loved it all. I have only a couple of days to spend at Santiago before the final departure on Thursday, to head to Greece. A process ends but another starts.

For lunch with the group (clockwise from left): Ignacio Araya, Michel Cure, Lydia Cidale, Maxi Haucke, Catalina Arcos, Alex Gormaz, and me (I do not smile because I really couldn’t keep my eyes open due to the Sun!)
[Photo by Ignacio]

A memory from Valparaiso.
Gracias a tod@s por todo!
[Photo by Michel]

A short talk for IFA-UV Monday meetings

Every Monday the IFA-UV organizes a meeting that starts with a short (or longer) presentation of 20 mins. The whole process requires the active participation by the students to present the speaker, control, the discussion, while there is also a feedback given by the audience to the speaker. This is a great opportunity for the students to help them gain experience especially when they have to present. However, the topics (and the stage) is open to everyone. And this Monday was my turn to present a short talk on:

“Searching for Hα counterparts of Be/X-ray binaries in the Small Magellanic Cloud”

Abstract: The Small Magellanic Cloud (SMC) hosts a large number of high-mass X-ray binaries, and in particular of Be/X-ray Binaries (BeXRBs; neutron stars orbiting OBe-type stars), offering a unique laboratory to address the effect of metalicity. One key property of their optical companion is Hα in emission, which makes them bright sources when observed through a narrow-band Hα filter. We performed a survey of the SMC Bar and Wing regions using wide-field cameras (WFI@MPG/ESO and MOSAIC@CTIO/Blanco) in order to identify the counterparts of the sources detected in our XMM-Newton survey of the same area. We obtained broad-band R and narrow-band Hα photometry, and identified ~10000 Hα emission sources down to a sensitivity limit of 18.7 mag (equivalent to ~B8 type Main Sequence stars). We find the fraction of OBe/OB stars to be 13% down to this limit, and by investigating this fraction as a function of the brightness of the stars we deduce that Hα excess peaks at the O9-B2 spectral range. Using the most up-to-date numbers of SMC BeXRBs we find their fraction over their parent population to be ~0.002-0.025 BeXRBs/OBe, a direct measurement of their formation rate.

After the talks it comes another important step which is the wine and cheese ceremony, accompanying the informal discussions.

An IFA-UV seminar talk

Yesterday, I had finally the opportunity to give a seminar talk at the Instituto de Física y Astronomía de la Universidad de Valparaíso, where I am currently based (and only for about a month more …)

“What have we learned from observations of B[e] Supergiants ?”

Abstract:
B[e] Supergiants are a rare phase among the massive stars, displaying a complex circumstellar environment. However, they may provide an important link to other phases (e.g. the Yellow Hypergiants, the Luminous Blue Variables). Given the importance of massive stars for Stellar Astrophysics and their influence on their host galaxies it is critical to understand their evolution. Starting from an observational point of view, I will provide an overview of the B[e] Supergiants and discuss the latest results.